text:
Conceptual frameworks, models, theories, definitions

Module name
Conceptual frameworks, models, theories, definitions

Scope
Introduction to several conceptual models characterizing the DL domain (Digital Libraries Reference Model-DLRM, 5S, DELOS Classification and Evaluation Scheme, CIDOC Conceptual Reference Model, DOLCE-based Ontologies for Large Software Systems)

Learning objectives:

 * a. Students will be provided with a high level yet comprehensive knowledge of several conceptual frameworks and models;
 * b. Students will be provided with a unifying and extended terminology;
 * c. Students will be provided with an overall scheme helping to classify further readings;

Level of effort required (in-class and out-of-class time required for students)
Prior to class: 4 hours for readings In class: 2,5 hours Exercises: 3 hours

Relationships with other modules (flow between modules)
Introductory, can be read independently from other modules. If, however, read at the beginning, it can offer a better understanding of other modules.

Prerequisite knowledge/skills required (completion optional)
N/A

Introductory remedial instruction (completion optional; the body of knowledge for the prerequisite knowledge/skills required)
N/A

Body of knowledge (Theory + Practice)
(Topics might be skipped or studied in different orders)

The Digital Libraries Reference Model
What is a Reference Model

 * A reference model is an abstract framework for understanding significant relationships among the entities of some environment, and for the development of consistent standards or specifications supporting that environment
 * A reference model is based on a small number of unifying concepts and may be used as a basis for education and explaining standards to a non-specialist
 * A reference model is not directly tied to any standards, technologies or other concrete implementation details, but it does seek to provide a common semantics that can be used unambiguously across and between different implementations.

Objective and structure of the Digital Libraries Reference Model

Sets the foundations and identifies the cornerstone concepts within the universe of Digital Libraries, facilitating the integration of research and proposing better ways of developing appropriate systems. Reflecting the structure of the DL universe the DLRM is segregated into six (6) sub-domains comprising interrelated concepts and terms i.e. the Content, User, Functionality, Quality, Policy and Architecture domains. Concepts from each of these sub-domains are materialized in nearly every existing DL. These concepts are further analyzed next.

In terms of document structure the DLRM consists of 3 parts:
 * Digital Library Manifesto
 * Digital Library Reference Model in a Nutshell
 * Digital Library Reference Model Concepts & Relations.

The Reference Model fundamentals

A Three-tier Framework

Digital Library (DL)
 * An organisation, which might be virtual, that comprehensively collects, manages and preserves for the long term rich digital content, and offers to its user communities specialised functionality on that content, of measurable quality and according to codified policies.

Digital Library System (DLS)
 * A software system that is based on a defined (possibly distributed) architecture and provides all functionality required by a particular Digital Library. Users interact with a Digital Library through the corresponding Digital Library System.

Digital Library Management System (DLMS)
 * A generic software system that provides the appropriate software infrastructure both (i) to produce and administer a Digital Library System incorporating the suite of functionality considered fundamental for Digital Libraries and (ii) to integrate additional software offering more refined, specialised or advanced functionality.

The Constituent Domains The Digital Library Domain, which comprises all the elements needed to represent the three systems of the DL universe, is divided into two main classes: DL Resource Domain and Complementary Domain.The DL Resource Domain contains elements identified as ‘first class citizens’ in modelling the Digital Library universe. The classification is as follows:

Content

 * The Content concept encompasses the data and information that the Digital Library handles and makes available to its users. It is composed of a set of information objects organised in collections. Content is an umbrella concept used to aggregate all forms of information objects that a Digital Library collects, manages and delivers. It encompasses the diverse range of information objects, including such resources as objects, annotations and metadata. For example, metadata have a central role in the handling and use of information objects, as they provide information critical to its syntactical, semantic and contextual interpretation.

User

 * The User concept covers the various actors (whether human or machine) entitled to interact with Digital Libraries. Digital Libraries connect actors with information and support them in their ability to consume and make creative use of it to generate new information. User is an umbrella concept including all notions related to the representation and management of actor entities within a Digital Library. It encompasses such elements as the rights that actors have within the system and the profiles of the actors with characteristics that personalise the system’s behaviour or represent these actors in collaborations.

Functionality

 * The Functionality concept encapsulates the services that a Digital Library offers to its different users, whether classes of users or individual users. While the general expectation is that DLs will be rich in capabilities and services, the bare minimum of functions would include such aspects as new information object registration, search and browse. Beyond that, the system seeks to manage the functions of the Digital Library to ensure that the functions reflect the particular needs of the Digital Library’s community of users and/or the specific requirements relating to the Content it contains.

Quality

 * The Quality concept represents the parameters that can be used to characterise and evaluate the content and behaviour of a Digital Library. Quality can be associated not only with each class of content or functionality but also with specific information objects or services. Some of these parameters are objective in nature and can be measured automatically, whereas others are subjective in nature and can only be measured through user evaluations (e.g. focus groups).

Policy

 * The Policy concept represents the set or sets of conditions, rules, terms and regulations governing interaction between the Digital Library and users, whether virtual or real. Examples of policies include acceptable user behaviour, digital rights management, privacy and confidentiality, charges to users, and collection delivery. Policies belong to different classes; for instance, not all policies are defined within the DL or the organisation managing it. The policy supports the distinction between extrinsic and intrinsic policies. The definition of new policies and re-definition of older policies will be a feature of digital libraries.

Architecture

 * The Architecture concept refers to the Digital Library System entity and represents a mapping of the functionality and content offered by a Digital Library on to hardware and software components.

The Complementary Domain contains all the other domains, which, although they do not constitute the focus of the digital libraries and can be inherited from existing models, are nevertheless needed to represent the systems. This concept serves as a placeholder for domains different from those identified as ‘first class citizens’ and as a hook for future extensions of the model. It includes concepts such as:
 * Time Domain (i.e. concepts and relations needed to capture aspects of the time sphere such as time periods and intervals);
 * Space Domain (i.e. concepts and relations needed to capture aspects of the physical sphere such as regions and locations);
 * Language Domain (i.e. concepts and relations needed to capture aspects of the method of communication, either spoken or written, consisting of the use of words in a structured and conventional way).

Players acting in the DL universe
 * The DL End-Users are the ultimate clients the Digital Library is going to serve.
 * They exploit the DL functionality for providing, consuming, and managing the DL Content as well as some of its other constituents. They perceive the DL as a state full entity that serves their functional needs. DL end-users may be further partitioned into • Content Creator • Content Consumer • Librarian

 * The DL Designers are the organisers and orchestrators of the Digital Library from the application point of view.
 * They exploit their knowledge of the application semantic domain to define, customize, and maintain the Digital Library so that it is aligned with the information and functional needs of its end-users. To perform this task, they interact with the DLMS providing functional and content configuration parameters.

 * The DL System Administrators are the organisers and orchestrators from the physical point of view.
 * They select the software components necessary to create the Digital Library System needed to serve the required DL and decide where and how to deploy them. They interact with the DLMS by providing architectural configuration parameters, such as the selected software components, the hosting nodes, and the components allocation.

 * The DL Application Developers are the implementers of the software parts needed to realise the Digital Library.
 * They develop the software components of DLMSs and DLSs, realizing the necessary functionality

The 5S Framework: Streams, Structures, Spaces, Scenarios and Societies
The 5S Framework is the result of an activity aimed at defining digital libraries in a rigorous manner. It is based on five fundamental abstractions, namely Streams, Structures, Spaces, Scenarios and Societies. These five concepts are informally defined as follows:
 * Streams are sequences of elements of an arbitrary type (e.g. bits, characters, images) and thus they can model both static and dynamic content. Static streams correspond to information content represented as basic elements, e.g. a simple text is a sequence of characters, while a complex object like a book may be a stream of simple text and images. Dynamic streams are used to model any information flow and thus are important for representing any communication that takes place in the digital library. Finally, streams are typed and the type is used to define their semantics and application area.
 * Structures are the way through which parts of a whole are organised. In particular, they can be used to represent hypertexts and structured information objects, taxonomies, system connections and user relationships.
 * Spaces are sets of objects together with operations on those objects conforming to certain constraints. This type of construct is powerful and, as suggested by the conceivers, when a part of a DL cannot be well described using another of the 5S concepts, space may well be applicable. Document spaces are the key concepts in digital libraries. However, spaces are used in various contexts – e.g. indexing and visualising – and different types of spaces are proposed, e.g. measurable spaces, measure spaces, probability spaces, vector spaces and topological spaces.
 * Scenarios are sequences of events that may have parameters, and events represent state transitions. The state is determined by the content in a specific location but the value and the location are not investigated further because these aspects are system dependent. Thus a scenario tells what happens to the streams in spaces and through the structures. When considered together, the scenarios describe the services, the activities and the tasks representing digital library functions. DL workflows and dataflows are examples of scenarios.
 * Societies are sets of entities and relationships. The entities may be humans or software and hardware components, which either use or support digital library services. Thus, society represents the highest-level concept of a Digital Library, which exists to serve the information needs of its societies and to describe the context of its use.

We can relate the 5S to some of the aims of a Digital Library: These concepts are of general purpose and represents low-level constructors. Using these concepts, Gonçalves et al. introduced a DL ontology. In this ontology, the different Ss are defined starting from basic mathematical concepts, such as graph or function, and are then combined and used to introduce the specific concepts that characterise the Digital Library universe. For example, the concept of digital object is defined in terms of the streams and structures that constitute it and, in turn, is used for introducing the concept of collection. In accordance with this framework, Gonçalves et al. define a minimal Digital Library as a quadruple (R,Cat,Serv,Soc) where:
 * Societies define how a Digital Library helps in satisfying the information needs of its users.
 * Scenarios provide support for the definition and design of different kinds of services.
 * Structures support the organisation of the information in usable and meaningful ways.
 * Spaces deal with the presentation and access to information in usable and effective ways.
 * Streams concern the communication and consumption of information by users.

On top of this, a framework aimed at arranging the concepts and identifying the relationships between them has been proposed.
 * 1) R is a repository, a service encapsulating a family of collections and specific services (get, store and del) to manipulate the collections;
 * 2) Cat is a set of metadata catalogues for all collections in the repository;
 * 3) Serv is a set of services containing at least services for indexing, searching and browsing; and
 * 4) Soc is a society.

Comparison: Reference Model and 5S
There is a correspondence between the area covered by the 5S framework and the Reference Model: 5S basically covers what in the Reference Model have been called Content, Functionality and User main concepts; the Quality main concept has been addressed separately in the 5S Quality model, while the Policy main concept has scarcely been dealt with in the 5S framework. Moreover, the degree of detail in the different areas can vary, since in some areas the 5S framework introduces very fine-grained concepts while in other areas it adopts a more high-level approach; similar considerations also hold for the Reference Model.

Besides the above difference, it is also important to note the similarity arising around the notion of Information Object, termed digital object in the 5S framework. This probably indicates that the information object concept has been investigated more and is probably better understood than other elements constituting the Digital Library universe.

The DELOS Classification and Evaluation Scheme
The DELOS Working Group dealing with the evaluation of digital libraries problem proposed a model that is broader in scope than the one usually adopted in the evaluation context. The aim is to be able to satisfy the needs of all DL researchers, either from the research community or from the library community. This group started from a general-purpose definition of Digital Library and identified three non-orthogonal components within this digital library domain: the users, the data/collection and the chosen system/technology. These entities are related and constrained by means of a series of relationships, namely: By relying on these core concepts and relationships, it is possible to move outwards to the DL Researcher domain and create a set of researcher requirements for a DL test-bed. Recently, this model has been enriched by focusing on the inter-relationships between the basic concepts, i.e. the User–Content relationship is related to the usefulness aspects, the Content–System relationship is related to the performance attributes, while the User–System is related to usability aspects. For each of these three aspects, techniques and principles for producing quantitative data and implementing their evaluation have been introduced. The Reference Model addresses similar issues through the Quality domain (please check section 9.1). While the evaluation framework takes care of identifying the characteristics of the DL systems to be measured and evaluated, the Digital Library Reference Model introduces this notion at the general level of Resource, i.e. each Resource is potentially subject to various judgment processes capturing different perspectives.
 * 1) 	the definition of the set of users predefines the range and content of the collection relevant and appropriate for them;
 * 2) 	the nature of the collection predefines the range of technologies that can be used; and
 * 3) 	the attractiveness of the collection content with respect to the user needs and the ease of use of the technologies by these users determine the extent of usage of the DL.

The CIDOC Conceptual Reference Model
The CIDOC Conceptual Reference Model (CRM) is an initiative whose goal is to provide a model, i.e. a formal ontology, for describing implicit and explicit concepts and relationships needed to describe cultural heritage documentation. This activity started in 1996 under the auspices of the ICOM-CIDOC Documentation Standard Working Group and since December 2006 it has been an official ISO standard (ISO 21127:2006).

It consists of 81 classes, i.e. categories of items sharing one or more common traits, and 132 unique properties, i.e. relationships of a specific kind linking two classes. Moreover, classes as well as properties are organised in a hierarchy through the ‘is a’ relationship.

The CIDOC reference model classifies the rest as the CRM Entity, i.e. the class comprising all things in the CIDOC universe and the Primitive Value class, i.e. the class representing values used as documentation elements (Number, String and Time Primitive). This second class is not elaborated further. The entities of the CIDOC universe are further classified in Temporal Entity, i.e. phenomena and cultural manifestations bounded in time and space; Persistent Item, i.e. items having a persistent identity; Time-Span, i.e. abstract temporal extents having a beginning, an end and a duration; Place, i.e. extents in space in the pure sense of physics; and Dimension, i.e. quantifiable properties that can be approximated by numerical values.

The Persistent Item class can be compared to our notion of Resource as univocal identified entity (Resource Identifier). It is further specialised to form a hierarchy. Thing is the direct subclass and represents usable discrete, identifiable instances of persistent items documented as single units. At this point a complex hierarchy of things classes is introduced. In this hierarchy three classes need to be further explained, namely Conceptual Object, Information Object and Collection. A Conceptual Object is defined as ‘non-material product of our minds, in order to allow for reasoning about their identity, circumstances of creation and historical implications’. It shares many commonalities with the IFLA-FRBR concept of Work, while its counterpart in the Digital Library Reference Model is the Information Object. The CIDOC-CMR Information Objects are defined as ‘identifiable immaterial items, such as poems, jokes, data sets, images, texts, multimedia objects, procedural prescriptions, computer program code, algorithm or mathematical formula, that have an objectively recognisable structure and are documented as single units’. The CIDOC Information Object concept falls within the concept of Information Object of the Digital Library Reference Model. The CIDOC model takes care of complex Information Objects through the ‘is composed of’ property as well as of rights ownership through the linking between Legal Object and Right. Collection is defined as ‘aggregation of physical items that are assembled and maintained by one or more instances of Actor over time for a specific purpose and audience, and accounting to a particular collection development plan’. Thus, differing from the Digital Library Reference Model, the CIDOC-CRM only refers collections to physical instantiation of such aggregative mechanism.

Actor, i.e. people who individually or as a group have the potential to perform actions of which they can be deemed responsible, is introduced as a specialisation of the Persistent Item class. This concept presents many commonalities with the one introduced in the Digital Library Reference Model and presented in Section 9.1. Another specialisation of the Persistent Item class is Appellation, i.e. any sort of identifier that can be used to identify specific instances of all the classes. The two models dedicate a different effort to modelling this aspect. While the Digital Library Reference Model introduces the concept of Resource Identifier without specialising it, the CIDOC-CRM introduces many specialisations ranging from Object Identifier to Address, Title and Date. Finally, the CIDOC-CRM captures also aspects related to the notion of Functionality. In fact, even if its goal is to provide an ontology for modelling cultural heritage information, some of its classes aim at capturing the history and evolution of such information and thus can be considered as a sort of Function to which objects/information have been subjected. In particular, the role of the Activity class is to comprise ‘actions intentionally carried out by instances of Actor that result in changes of state in the cultural, social, or physical systems documented’.

DOLCE-based Ontologies for Large Software Systems
DOLCE (Descriptive Ontology for Linguistic and Cognitive Engineering) is a foundational ontology developed to capture the ontological categories underlying natural language and human common sense. By relying on the basic constructs it iden tifies, a framework of a set of ontologies for modelling modularisation and communication in Large Software Systems has been developed. This framework consists of three ontologies:
 * 1) the Core Software Ontology (CSO);
 * 2) the Core Ontology of Software Components (COSC); and
 * 3) the Core Ontology of Web Services (COWS).

The first of these provides foundations for describing software in general. In particular, it introduces the notions of ‘Software’ and ‘ComputationalObject’, which represent respectively the encoding of an algorithm and the realisation of a code in a concrete hardware. These notions are similar to the Software Component and Running Component notions envisaged by the Reference Model. In addition, the CSO ontology introduces concepts borrowed from the object-oriented paradigm such as ‘Class’, ‘Method’ and ‘Exception’, which from the Reference Model point of view are considered fine-grained and relegated to Concrete Architecture models. This ontology contains also the concepts for dealing with access rights and policies. In particular, by relying on the ‘Descriptions & Situations’ constructs of the DOLCE ontology, the concepts of ‘PolicySubjects’ (which can be ‘Users’ or ‘UserGroups’), ‘PolicyObjects’ (which can be ‘Data’) and ‘TaskCollections’ (set of ‘ComputationalTasks’) are introduced. The former two aspects are captured in a general manner by the Reference Model through the relationship between the Resource and the Policy concepts, i.e. , and through the concept of Role (and Resource Set) with respect to the intuition behind ‘TaskCollections’. The Core Ontology of Software Components provides concepts needed to capture software components related aspects like libraries and licenses, component profiles and component taxonomies. The notion of ‘SoftwareComponent’ (having a ‘Profile’ aggregating knowledge about it) is the main entity in this ontology and it is formalised as a ‘Class’ that conforms to a ‘FrameworkSpecification’ (a set of ‘Interfaces’). Moreover, the notion of ‘SoftwareLibrary’ and ‘License’ completes the scenario by introducing notions for supporting the automatic check of conflicting libraries and incompatible licenses. The similarities with the set of concepts captured by the Reference Model Architecture Domain are evident. However, it is important to notice that the way the dependencies between the various components are captured by the Reference Model enables it to be more flexible with respect to this point.

The Core Ontology of Web Services reuses all the other ones to establish a well-founded ontology for Web Services. This is a very specific ontology that captures the component-oriented approach in terms of standards for protocols (SOAP) and descriptions (WSDL). The other interesting feature is the explicit introduction of the ‘QualityOfService’ parameters, which in the case of the Reference Model are captured through the general relationship, i.e. , between a Resource and its Quality Parameters.

Resources (textbooks, required and optional readings for instructors and students)

 * G. Athanasopoulos, L. Candela, D. Castelli, P. Innocenti, Y. Ioannidis, A. Katifori, A. Nika, G. Vullo, S. Ross, (2010) The Digital Library Reference Model version 1.0, DL.org: Coordination Action on Digital Library Interoperability, Best Practices and Modelling Foundations – Project Num: 231551

 * Gonçalves, M.A.; Fox, E.A.; Watson, L.T.; Kipp, N.A. ‘Streams, Structures, Spaces, Scenarios, Societies (5S): A Formal Model for Digital Libraries’. ACM Transactions on Information Systems (TOIS), 22(2), 270 –312, 2004

 * Gonçalves, M.A. Streams, Structures, Spaces, Scenarios, and Societies (5S): A Formal Model for Digital Library Framework and Its Applications. PhD thesis, Virginia Polytechnic Institute and State University, November 2004

 * Gonçalves, M.A.; Moreira, B.L.; Fox, E.A.; Watson, L.T. ‘What is a good digital library? – A quality model for digital libraries’. Information Processing & Management, 43(5), 1416–1437, 2007.

 * Fuhr, N.; Hansen, P.; Mabe, M.; Micsik, A.; Solvberg, I. (2001). ‘Digital Libraries: A Generic Classification and Evaluation Scheme’. In: ECDL’01: Proceedings of the 5th European Conference on Research and Advanced Technology for Digital Libraries, 187-199, London, UK.

 * Fuhr, N.; Tsakonas, G.; Aalberg, T.; Agosti, M.; Hansen, P.; Kapidakis, S.; Klas, C.-P.; Kovács, L.; Landoni, M.; Micsik, A.; Papatheodorou, C.; Peters, C.; Solvberg, I. (2006). ‘Evaluation of Digital Libraries’. International Journal of Digital Libraries, 2007 (online first).

 * Tsakonas, G.; Kapidakis, S.; Papatheodorou, C. ‘Evaluation of User Interaction in Digital Libraries’. In: Agosti, M.; Fuhr, N. (eds): Notes of the DELOS WP7 Workshop on the Evaluation of Digital Libraries, Padua, Italy, 2004. http://dlib.ionio.gr/wp7/workshop2004_program.html

 * IFLA Study Group on the Functional Requirements for Bibliographic Records. Functional Requirements for Bibliographic Records: Final Report. September 1997. http://www.ifla.org/VII/s13/frbr/frbr.htm (last visited 21 February 2007)

 * ISO 21127:2006 Information and documentation – A reference ontology for the interchange of cultural heritage information, December 2006.
 * Oberle, D.; Lamparter, S.; Grimm, S.; Vrandecic, D.; Staab, S.; Gangemi, A. ‘Towards Ontologies for Formalizing Modularization and Communication in Large Software Systems’. Journal of Applied Ontology, 2006.

 * Novak, J.D.; Cañas, A.J. The Theory Underlying Concept Maps and How to Construct Them, Technical Report IHMC CmapTools 2006-01, Florida Institute for Human and Machine Cognition, 2006

Concept maps
The Reference Model describes the Digital Library Universe by Concept Maps i.e. graphical tools for organizing and representing knowledge in terms of Concepts and Relationships Concept maps are graphical tools for organizing and representing knowledge in terms of concepts (entities) and relationships between concepts to form propositions. Concepts are used to represent regularity in events or objects, or records of events or objects. Propositions are statements about some objects or events in the universe, either naturally occurring or constructed. Propositions contain two or more concepts connected using linking words or phrases to form a meaningful statement. In the graphical representation, concepts are inscribed in circles or boxes, while propositions (proposition connectors) are represented as (directed) lines connecting concepts, labeled with words describing the linking relationship.

Exercises / Learning activities
A.	Describe one or more existing DL / DLS in terms of the concepts and constructs of the Digital Libraries Reference Model

B.	The main actor of this scenario is a digital librarian called D. D has been given the task of designing an information discovery service that integrates 3 different services: Wikipedia, Amazon and Europeana. The objective of the service is to offer to its users, for a given topic:

 * 1) an account of the topic (taken from Wikipedia)
 * 2) a list of resources in Europe related to the topic (Europeana)
 * 3) a list of the available publications on the topic (Amazon)
 * 4) the links between these 3.

In addition the digital librarian D should design a mechanism that integrates the three different user models supported by the respective systems.
 * Wikipedia has a user model capturing username and password of the user, as well as his real name. Other features include the names of the groups that the user belongs to and the edits the user has made on the wiki. Optional features include email and gender. When the user is registered he may have access to advanced preferences and editing options. These include the specification of the language in which the site interface will be displayed, the appearance of date and time, as well as user’s time zone.
 * Europeana has a user model that captures username, password, and email address. Additional characteristics include country, language settings, IP address, the date and time the user accessed the website, and the pages the user requested for viewing.
 * Amazon has a user model that includes name, email address, and password. Optional is user’s birth date. Additional characteristics include payment options, shipping address, and a list of past orders.

Questions:

- Based on the above information define the functionality offered by each of the specified DLs in the context of this scenario in terms of the DL Reference Model

- Specify the user models supported by the respective DLs in terms of the DL Reference Model

Evaluation of learning objective achievement
In their answers to the exercises, students demonstrate an understanding of They will further elaborate on functionality and user related issues
 * 1) the main concepts of the DLRM
 * 2) the existing roles in the DL universe

Glossary
N/A

Additional useful links

 * http://www.dlorg.eu/ - The website of the DL.org project

 * http://etraining.dlorg.eu/ - Training modules based on the DLRM

 * http://www.dlorg.eu/uploads/DL%20Reference%20Models/D3.2aTheDigitalLibraryReferenceModel_web.pdf - The Digital Libraries Reference Model

 * http://www.loa-cnr.it/DOLCE.html - The website of the Laboratory for applied Ontology

 * http://cidoc.ics.forth.gr - The website of the CIDOC Conceptual Reference Model

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
Talk:Limits To Growth

organizing and categorizing the limits
These limits can be organized or categorized by: Material, Energy, and Waste disposal, and by renewable or non-renewable resources, and source or sink.--Lbeaumont 12:34, 15 February 2011 (UTC)

Organizing by Footprint Categories
Consider organizing the resources according to these catagories:

They are (i) growing crops for food, animal feed, fiber, oil, and rubber; (ii) grazing animals for meat, hides, wool, and milk; (iii) harvesting timber for wood, fiber, and fuel; (iv) marine and freshwater fishing; (v) accommodating infrastructure for housing, transportation, industrial production, and hydro-electric power; and (vi) burning fossil fuel.

These are used in the paper at: www.pnas.org/cgi/doi/10.1073/pnas.142033699

System Dynamic Model of Fertile Soil
I am looking for a system dynamic model of fertile soil. This would describe decay of organic matter, etc. over a long period of time (e.g. centuries) as the primary generative flow and describe agriculture activities (growing and harvesting crops, water flows, fertilizer use, etc) as the primary depletion flows. The quantity and quality (e.g. fertility) of the soil would both be modeled. If you know of such a model, please let me know. Thanks! --Lbeaumont 14:54, 10 March 2011 (UTC)

Simcity meets limits to growth
it would be way cool to have a game along the lines of simcity based on the world3 limits to growth model. Students could play the game (create simulation runs) based on their own decisions for allocating resources and consuming resources. It could bring the concepts alive and increase awareness and ownership for analogous decisions in the real world. --Lbeaumont 13:18, 12 March 2011 (UTC)

Limits to economic growth
I have felt that economic growth is capital construction resulting economic shrinking. A recent attempt to work w/ the wikimedia foundation showed me that wiki growth also answers to the limited growth equation. As an example of economics, the DOW index has been shrinking for 30-40 years if you account for inflation--which they don't. Growth prior to the shrinking was the result of shifting power after WWII, I think.

Point being, if you are not growing, no reason to attempt to be as if you are. So what is growth? Illusion. But environmental deprecation is real: real vs. illusion. The illusionists will tell you that they are your reality,and call the police if you need to be reminded: smoke, mirrors and court appearances.--JohnBessatalk 21:52, 16 May 2011 (UTC)
 * I suggest reading the book "Prosperity Without Growth" by Tim Jackson --Lbeaumont 12:27, 4 June 2011 (UTC)

To-do list
lots of work remains to be done throughout the course, including these significant efforts: --Lbeaumont 19:49, 23 May 2011 (UTC)
 * create waste / sink input-output flow diagrams. For each major waste type identify the major sources and their flow rates worldwide and per unit. Identify the major sinks and the flow rates and assimilation rates.
 * establish quantitative limits for each resource. Include food for all, CO2 limits, etc. Use the limits TED talk and other sources.
 * establish a "standard human" in terms of their consumption of food, water, energy, materials, and waste products.
 * describe "my corner of the earth" by dividing land area and other resources by the total population to illustrate how much land we each have and how it is allocated to forest, crops, living space, water, etc per person.
 * draw the macro-level interrelationship diagram for the overall system.
 * develop the concept of prosperity without growth
 * integrate Khan Academy style videos into each lesson.
 * Create PowerPoint-style slides for each lesson.

Radioactivity of Brine
Hi Lbeaumont!

While scanning my usual science email from Nature Briefing there was "The lesser-known radioactive waste" in which was written "Every year, oil and gas wells in the United States produce nearly 4 trillion litres of ‘brine’: water contaminated with radioactive isotopes pulled up from beneath Earth’s surface. Because it is naturally occurring and exempted from some environmental regulations, brine has avoided the oversight and scientific scrutiny of nuclear waste. Rolling Stone investigates how this lesser-known toxic waste is affecting workers and communities." Here's the weblink: The lesser-known radioactive waste. Perhaps you'll want to enter it into Limits To Growth. --Marshallsumter (discuss • contribs) 22:59, 23 January 2020 (UTC)

title: Talk:Limits To Growth


text:
User:Eml5526.s11.team6.deshpande/hwk3

=Problem 3.2= For the spring system shown in the figure below in given data.

Find
A. Number the elements and nodes.

B. Assemble the global stiffness and force matrix.

C. Partition the system and solve for the nodal displacements.

D. Compute the reaction forces.

Given
Spring system with closed ends as shown in the figure

Solution
A: The elements and nodes are numbered as follows: Element numbers are indicated in parentheses and node numbers are indicated at the bottom of the figure.

B: The elements of the stiffness matrices are:

Where global numbers corresponding to the element nodes are indicated above each column and to the right of each row.

By direct assembly, we get the global stiffness matrix as follows

The displacement and force matrices are as follows

Combined force matrix can be written as

C: Now the global system of equations is

As first two displacements are prescribed, partition after two rows and two columns. We get,

Where,

From eq.(3.2.10), we can write

From equations (3.2.12), (3.2.13), (3.2.14), (3.2.15), we get,

and

Solving above two equations, we get

D:Calculation of the reaction forces

From eq.(3.2.10), we can also write

From equations (3.2.11), (3.2.13), (3.2.14), (3.2.19), we get,

and

Solving above two equations, we get

=6=

= Problem 6.7 Rules of Matrix algebra=

Solution
Hence, Therefore, Now, Hence, from eq. (6.7.6) and eq. (6.7.11)

Now, Using eq. (6.7.8), we can write Verified using | Wolfram Alpha

Hence, from eq.(6.7.14) and eq.(6.7.15) we can say that

=Problem 6.8=

Solution
Nodes and weights for the 5-point Gauss–Legendre formula according to | NIST Handbook are as follows:

For the table given in the problem statement, the calculated value of each term is as follows

In Fish and Belytschko's book on page 89 The position of Gauss points and corresponding weights are as follows

Hence, from the above tables we can conclude that the table given in problem statement (from [[media:fe1.s11.mtg36.djvu|Mtg 36 (a,x)]]) is reasonably accurate when compared to the above tables from NIST handbook and Fish and Belytschko's book on page 89.

title: User:Eml5526.s11.team6.deshpande/hwk3


text:
User talk:DL.orgMember

 Hello DL.orgMember, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. All users are expected to abide by our Privacy policy, Civility policy, and the Terms of Use while at Wikiversity.

To get started, you may

 * Take a guided tour and learn to edit.
 * Visit a (kind of) random project.
 * Browse Wikiversity, or visit a portal corresponding to your educational level: pre-school, primary, secondary, tertiary, non-formal education.
 * Find out about research activities on Wikiversity.
 * Explore Wikiversity with the links to your left.

 * Read an introduction for teachers and find out how to write an educational resource for Wikiversity.
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You don't need to be an educator to edit. You only need to be bold to contribute and to experiment with the sandbox or your userpage. See you around Wikiversity! --Ottava Rima (talk) 14:05, 15 February 2011 (UTC)

title: User talk:DL.orgMember


text:
User talk:Waihorace

 Hello Waihorace, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. All users are expected to abide by our Privacy policy, Civility policy, and the Terms of Use while at Wikiversity.

To get started, you may

 * Take a guided tour and learn to edit.
 * Visit a (kind of) random project.
 * Browse Wikiversity, or visit a portal corresponding to your educational level: pre-school, primary, secondary, tertiary, non-formal education.
 * Find out about research activities on Wikiversity.
 * Explore Wikiversity with the links to your left.

 * Read an introduction for teachers and find out how to write an educational resource for Wikiversity.
 * Give feedback about your initial observations
 * Discuss Wikiversity issues or ask questions at the colloquium.
 * Chat with other Wikiversitans on #wikiversity-en.
 * Follow Wikiversity on twitter (http://twitter.com/Wikiversity) and identi.ca (http://identi.ca/group/wikiversity).

You don't need to be an educator to edit. You only need to be bold to contribute and to experiment with the sandbox or your userpage. See you around Wikiversity! --Ottava Rima (talk) 14:05, 15 February 2011 (UTC)

title: User talk:Waihorace


text:
User talk:Romistrub

Signing contributions
On Talk pages or places where your user name and a timestamp would be useful, you can create this quickly by using ~ (four tildes). For example, at the end of this, I'm writing --~ and the software will substitute my user name and timestamp. If you have any questions or need help, you can ask me on User talk:Abd.

Do you know it took me a year on Wikipedia to figure this out? Again, welcome. --Abd 17:21, 15 February 2011 (UTC)

 * Yeah, the syntax on here is pretty dense! Thanks for the welcome and the info! --Romistrub 17:29, 15 February 2011 (UTC)

title: User talk:Romistrub


text:
Engineering Experience 4: Design a Small Solar Vehicle/Nl/Groep 4

Introduction
Het doel van dit EE4-project is het ontwerpen, bouwen en optimaliseren van een Small Solar Vehicle (SSV). Na 11 weken dient dit wagentje afgewerkt te zijn en neemt het team er mee deel aan een race. In deze race legt de SSV een recht parcours van 14 meter af waarvan 6 meter vlak en de laatste 8 meter onder een helling van 3 procent. Het meest innovatieve en mooiste wagentje zullen tevens extra beloond worden.

Voor de realisatie van project krijgt elk team een zonnepaneeltje met bijhorende motor ter beschikking. Daarnaast is er een budget voorzien van maximum 200 euro en de mogelijkheid tot het gebruiken van Fablab.


text:
User:Egm5526.s11.team4.zou/HW1

 * $$\displaystyle \int_{0}^{2}{\left( {{\beta }_{1}}+2{{\beta }_{2}}x \right)E\left( {{\alpha }_{1}}+2{{\alpha }_{2}}x \right)dx-\int_{0}^{2}{\left( {{\beta }_{1}}x+{{\beta }_{2}}{{x}^{2}} \right)10dx-}}{{\left. \left( ({{\beta }_{1}}x+{{\beta }_{2}}{{x}^{2}}) \right) \right|}_{x=2}}=0$$

 * $$\displaystyle \int_{0}^{2}{10\omega Axdx}$$

title: User:Egm5526.s11.team4.zou/HW1


title: File:3-5-1.png


title: File:3-5-2.PNG


title: File:3-5-3.png


title: File:3-5-4.png


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User:Romistrub

=Editing Wikis is Hard= After a million years of experimentation, I have discovered the force single spacing functionality!

s      s                     s

s                              s

</romistrub:t> my signature is cooler than yours.

Lesson One: Reading? Everything is a link. What the hell, right? Okay, I know that's not true, but it might as well be. You'd better check your trigger-finger or you'll be tumbling and fumbling like a clumsy ninja. A wiki is actually a perpetual motion machine powered by a cycle of anxiety and optimism. To save yourself, you must master categories, navigation boxes, and infoboxes. Curious yet? Oh, it knows.

 * Lesson Two: Editing? Everything is a template. If links weren't enough, add a whole new level of coordinated obfuscation to the mix. As far as I can tell, it's templates all the way down.

 * Lesson Three: The writing and editing "standards" are more like guidelines entertainment. There are a dozen or so for everything you might want to do. Pick one and run with it. Or don't -- that seems to work just fine, too. Just for shits, the standards are standardized using the standards you don't understand.

 * Lesson Four: Wiki is a Lifestyle. It's an entire universe, settling down for a family dinner, bitching politely about manners, fighting pleasantly over who can make the best origami napkins, drooling on the food and stealing leftovers. And everybody pees on the same tree. Luckily there's an army of Roombas (?) to the pick up the shattered ideals.

 * Lesson Five: The syntax is actually an inside-joke that only web-servers understand. The power users have learned how to smile and nod. Nobody laughs. There is no joy. The source code, although ambiguous, is not white-space-friendly, which has actually saved me substantial time by allowing me to ignore important information without realizing it.

 * Lesson Six: "Browsing" a wiki is the most efficient path to insanity. Everything is distracting. Everything looks the same. It's a texticular cancer. Riddles of black and blue, jokers in red, the purple burn of a ticking clock. Tunnel vision... of... disjointed ideas -- close proximity... sequence... rapid succession. Violent... uncontrollable... time-travel... 1995

 * Lesson Seven: Just because you can picture a house, doesn't mean you can find it. Some day, I vow this will work

=Some Breadcrumbs= w:Help:Wiki_markup w:Help:Template w:Wikipedia:WikiProject_Templates w:Help:Calculation w:Template:Trim/doc

What Links Here

My Pages
 My Contributions

Special:Watchlist

w:Wikipedia:Template_messages

title: User:Romistrub


text:
User:Romistrub/sandbox

School of Education Sandbox

title: User:Romistrub/sandbox


text:
User:Romistrub/sandbox/School:Education

 * so you want to know everything

it's not as hard as you've been told it must be

 * school of metology
 * school of knowledge integration

title: User:Romistrub/sandbox/School:Education


text:
User:Egm6321.f10.try

=Problem 7.2 Static and Dynamic Finite Element Modelling and Analysis for Vibrating Membrane=

Given: Problem defined on [[media:fe1.s11.mtg40.djvu|Mtg 40 (c)]]
Strong Form

Essential boundary conditions,

Find
1. Find the static solution $$ \quad U_{s}^h $$ to $$ \quad 10^{-6} $$ accuracy at x = 0.

2. Dynamic (Transient) Solution

2a. Free Vibration Analysis

2b. Plot $$ u^h(0,t) \ vs \ t \quad  for \ t \ \epsilon \ [0,2T_1]$$  and produce a movie of the vibrating membrane for symmetric

2c. Plot $$ u^h(0,t) \ vs \ t \quad  for \ t \ \epsilon \ [0,2T_1]$$  and produce a movie of the vibrating membrane for non-symmetric

i. Weak Form
From the PDE the weak form can be written as: Now from the theory of Integration by parts, we can write

Hence Eq. 2.1 can be now written as

Now we can write $$\displaystyle d\Omega $$ as $$\displaystyle d\Omega ={{\Gamma }_{g}}\cup {{\Gamma }_{h}}$$ , where $$\displaystyle {{\Gamma }_{g}}$$ = essential boundary condition. $$\displaystyle {{\Gamma }_{h}}$$ = natural boundary condition.

So by applying the Gauss theorem on the first term we obtain,

We select $$\displaystyle w $$ such that $$\displaystyle w=0 $$ on $$\displaystyle {{\Gamma }_{g}}$$

This Equation is of the form:- where,

ii. Finding approximate solution
Approximated solution $$ u^{h} \left ( x \right ) $$ and $$ w^{h} \left ( x \right ) $$ :

where $$ \left ( c_{i} \right ) $$ and $$ \left ( d_{j} \right ) $$ are constants and $$ \left ( b_{i} \right ) $$ and $$ \left (b_{j}\right ) $$ are the LIBF. We will use these LIBF as a shape function satisfying the CBS.

2DLIBF are given by

$$L_{i,m}$$ is the Lagrange basis function along x and $$L_{i,m}$$ is the Lagrange basis function along y given by

The LIBF be defined by a function

where,

Capacitance matrix

Conductivity matrix

Force matrix

1. Static solution
We have strong form of vibrating membrane equation (Eq. 2.1) where T = 4, $$f\left( x \right){\text{  =  1}}$$,  $$\quad $$   $$\quad \rho = 3 $$,  $$\quad $$ $$\qquad\frac{\partial^2u}{\partial t^2}=0$$

we can also write for 2D

$$\frac{{{\partial }^{2}}u}{\partial x_{i}^{2}}= \frac{\partial^2u}{\partial x_{1}^2} + \frac{\partial^2u}{\partial x_{2}^2}$$

If we rearrange Eq 2.1 for static case conditions, we get

2. Dynamic solution
$$ \quad \rho \ = \ 3$$

2a. Free Vibration Analysis
The equation is,

Where,

$$ \quad \lambda - Eigenvalues $$

$$\quad \mathbf{\phi} - Eigenvectors $$

We calculate eigenvalues and then put them into the equation below to find frequencies.

The fundamental frequency is $$\omega _{1}=\lambda_{1}^{1/2}$$, and  $$f_{1}=\frac{\omega _{1}}{2\Pi }$$. The period T is $$T_{1}=\frac{1}{f_{1}}$$

2b. Plotting displacement and the movie of the vibrating membrane for symmetric
Initial conditions:

2c. Plotting displacement and the movie of the vibrating membrane for non-symmetric
Initial conditions:

title: User:Egm6321.f10.try


text:
User talk:Romistrub/sandbox/School:Education

Make sure to use w:Wikipedia:Transclusion


text:
User:Egm6341.s11.team5.reiss/HW3

=Problem 8 - Verification of $$\left| E_2 \right|$$= From (meeting 17 page 3)

Given

 * {| style="width:100%" border="0" align="left"

\left| \right| \le \frac\int_a^b {\left| {(x - a)\left( {x - \frac{2}} \right)(x - b)} \right|dx} $$ $$
 * $$\displaystyle (8-1)
 * }
 * }

Find
Show that Eq (8-1) is
 * {| style="width:100%" border="0" align="left"

\displaystyle \begin{align} &=\frac{M_3} \\ &= \frac{M_3} \end{align} $$ $$
 * $$\displaystyle (8-2)
 * }
 * }

Solution

 * {| style="width:100%" border="0" align="left"

\displaystyle \begin{align} \frac\int_a^b {\left| {(x - a)\left( {x - \frac{2}} \right)(x - b)} \right|dx}&=\frac\int_a^{\frac{2}} {(x - a)\left( {-x + \frac{2}} \right)(-x + b)dx} \\ &+ \frac\int_{\frac{2}}^b {(x - a)\left( {x - \frac{2}} \right)(-x + b)dx} \end{align} $$ $$ Solving the first term
 * $$\displaystyle (8-3)
 * }
 * }
 * {| style="width:100%" border="0" align="left"

\frac\int_a^{\frac{2}} {(x - a)\left( {-x + \frac{2}} \right)(-x + b)dx}$$ $$= \int_a^{\frac{2}}- \frac{2} + \frac{2} - \frac{2} + 2abx - \frac{2} + \frac{2} - \frac{2} + {x^3} $$ $$=\left. { - \frac{2} + \frac{4} - \frac{2} + ab{x^2} - \frac{2} + \frac{4} - \frac{2} + \frac{4}} \right|_a^{\frac{2}}$$ $$\displaystyle (8-4) $$ Evaluating at $$x=\frac{b+a}{2}$$ and $$x=a$$ gives respectively
 * }
 * }
 * {| style="width:100%" border="0" align="left"

$$=- \frac{1}{4}{a^2}{b^2}$$ $$\displaystyle (8-5) $$ Expanding these terms and subtracting gives
 * $$=\frac{1}({a^2} + {b^2}){(a + b)^2} + \frac{3}{(a + b)^4}$$
 * $$=\frac{1}({a^2} + {b^2}){(a + b)^2} + \frac{3}{(a + b)^4}$$
 * }
 * }
 * {| style="width:100%" border="0" align="left"

$$\displaystyle (8-6) $$ Solving the second term
 * $$\frac{1}\left( {{a^4} - 4{a^3}b + 6{a^2}{b^2} - 4a{b^3} + {b^4}} \right) = \frac{1}{(b - a)^4}$$
 * $$\frac{1}\left( {{a^4} - 4{a^3}b + 6{a^2}{b^2} - 4a{b^3} + {b^4}} \right) = \frac{1}{(b - a)^4}$$
 * }
 * }
 * {| style="width:100%" border="0" align="left"

$$=\frac{2} - \frac{2} + \frac{2} - 2abx + \frac{2} - \frac{2} + \frac{2} - {x^3}$$ $$=\left. {\frac{2} - \frac{4} + \frac{2} - ab{x^2} + \frac{2} - \frac{4} + \frac{2} - \frac{4}} \right|_{\frac{2}}^b$$ $$\displaystyle (8-7) $$ Evaluating at $$x=b$$ and $$x=\frac{b+a}{2}$$ gives respectively
 * $$\frac\int_{\frac{2}}^b {(x - a)\left( {x - \frac{2}} \right)(-x + b)dx} $$
 * $$\frac\int_{\frac{2}}^b {(x - a)\left( {x - \frac{2}} \right)(-x + b)dx} $$
 * }
 * }
 * {| style="width:100%" border="0" align="left"

$$=- \frac{1}({a^2} + {b^2}){(a + b)^2} - \frac{3}{(a + b)^4}$$ $$\displaystyle (8-8) $$ Expanding these terms and subtracting gives
 * $$= \frac{1}{4}{a^2}{b^2}$$
 * $$= \frac{1}{4}{a^2}{b^2}$$
 * }
 * }
 * {| style="width:100%" border="0" align="left"

$$\displaystyle (8-9) $$ Adding Eq (8-6) and (8-9) as Eq (8-3) shows, we get
 * $$\frac{1}\left( {{a^4} - 4{a^3}b + 6{a^2}{b^2} - 4a{b^3} + {b^4}} \right) = \frac{1}{(b - a)^4}$$
 * $$\frac{1}\left( {{a^4} - 4{a^3}b + 6{a^2}{b^2} - 4a{b^3} + {b^4}} \right) = \frac{1}{(b - a)^4}$$
 * }
 * }
 * {| style="width:100%" border="0" align="left"

$$\displaystyle (8-10) $$ Then
 * $$\frac{1}{(b - a)^4}$$
 * $$\frac{1}{(b - a)^4}$$
 * }
 * }
 * {| style="width:100%" border="0" align="left"

$$\displaystyle (8-11) $$ Eq (8-11) is equivalent to Eq (8-2) therefor Eq (8-1) is equivalent to Eq (8-2)
 * $$\left( {\frac} \right)\left( {\frac{1}{{(b - a)}^4}} \right) = \frac$$
 * $$\left( {\frac} \right)\left( {\frac{1}{{(b - a)}^4}} \right) = \frac$$
 * }
 * }

title: User:Egm6341.s11.team5.reiss/HW3


text:
User:Eml5526.s11.team7.Srilalithkumar/HW3

hi there


text:
Wiki business plan/Energy

What is Energy?

There are several types of energy. Human energy. Fuel energy such as gasoline or biofuels. We can all understand electric energy that is running your PC right now.

Which types of energy do we want to teach about?

What types of energy do people want to learn about?

Energy development, or methods of producing electricity and power is our greatest challenge currently. More specifically sustainable energy is currently incapable of meeting the basics of expected energy levels for refrigeration, heat and air, lights etc. due primarily to poor battery capabilities.

High cost of initial per watt investments as well as the learning curve to operate alternative energy sources continues to be a challenge to realizing true solutions to our current energy challenges.

Unlike traditional grid based electrical systems you cannot simply flip a switch and forget about your energy with alternative energy such as solar.

Human energy, or the energy expended by people in order to achieve a certain goal or operation is also an area that needs to be evaluated. I.E. how do we reduce the amount of physical energy required in order to achieve certain goals. For example can we take people who have lower amounts of energy due to health or age and still achieve a certain level of production from them? Whether it be in the area of teaching or physical production. However there exists the potential to utilize the natural energy of the body to create electricity usable for our alternative electrical needs?

Overall this and other wikis could use some specific definitions to guide people to create worthwhile content development.

title: Wiki business plan/Energy


text:
User:Eml5526.sp11.team1.adam/HW3

Solution
The trial solution $$ u\left ( x \right )$$ and the weight function $$ w\left ( x \right )$$ can be written as follows:

$$ u\left ( x \right ) = \alpha_{0} + \alpha_{1}\left ( x-3 \right ) + \alpha_{2}\left ( x-3 \right )^{2}$$

$$ w\left ( x \right ) = \beta_{0} + \beta_{1}\left ( x-3 \right ) + \beta_{2}\left ( x-3 \right )^{2}$$

When:

$$ w \left(3 \right) = 0; \Rightarrow \beta_{0} = 0 $$

and for:

$$ u \left(3 \right) \Rightarrow \alpha_{0} = 0.001 $$

$$ u\left ( x \right )$$ and $$ w\left ( x \right )$$ can therefore be re-written as follows:

$$ u\left ( x \right ) = 0.001 + \alpha_{1}\left ( x-3 \right )+\alpha_{2}\left ( x-3 \right )^{2}$$

$$ w\left( x \right) = \beta_{1} \left(x - 3 \right)+\beta_{2}\left ( x-3 \right )^{2}$$

Whith their respective derivatives:

$$\frac{du}{dx} = \alpha_{1}+2\alpha_{2}\left(x-3\right)$$

$$\frac{dw}{dx} = \beta_{1}+2\beta_{2}\left(x-3\right)$$

Now substituting into the weak form yields:

$$ \int_{1}^{3} AE[\beta_{1}+2\beta_{2}\left(x-3\right)][\alpha_{1}+2\alpha_{2}\left(x-3\right)]dx = -0.1[A(\beta_{1}\left(x-3\right)+\beta_{2}\left(x-3\right)^{2})]_{x=1} + \int_{1}^{3} 2x[\beta_{1}\left(x-3\right)+\beta_{2}\left(x-3\right)^{2}]dx$$

which can be re-arranged as:

$$ \int_{1}^{3} AE[\beta_{1}+2\beta_{2}\left(x-3\right)][\alpha_{1}+2\alpha_{2}\left(x-3\right)]dx - 0.1[A(\beta_{1}\left(x-3\right)+\beta_{2}\left(x-3\right)^{2})]_{x=1} - \int_{1}^{3} 2x[\beta_{1}\left(x-3\right)+\beta_{2}\left(x-3\right)^{2}]dx = 0$$

Evaluating the integral we get:

$$ AE \left(2\alpha_{1}\beta_{1}-4\alpha_{1}\beta_{2}-4\alpha_{2}\beta_{1}+\frac{32\alpha_{2}\beta_{2}}{3}\right)- 0.1[A(4\beta_{2}-2\beta_{1})] - \left(8\beta_{2}-\frac {20\beta_{1}}{3}\right)=0 $$

Factoring out $$\left( \beta_{1}\right)$$ and $$\left( \beta_{2}\right)$$ we get:

$$\beta_{1}\left[2AE\left(\alpha_{1}-2\alpha_{2}\right)-0.2A+\frac{20}{3}\right]+\beta_{2}\left[4AE\left(\frac{8}{3}\alpha_{2}-\alpha_{1}\right)+0.4A-8\right]=0$$

$$\displaystyle {{\beta }_{1}}$$ and $$\displaystyle {{\beta }_{2}}$$ must be zero since they were arbitrarely chosen and because the above equation must hold. Therefore we can write both terms of the above equation equal to zeor as folows:

$$ \left[2AE\left(\alpha_{1}-2\alpha_{2}\right)-0.2A+\frac{20}{3}\right]=0$$

and

$$ \left[4AE\left(\frac{8}{3}\alpha_{2}-\alpha_{1}\right)+0.4A-8\right]=0 $$

Solving for $$\displaystyle {{\alpha }_{1}}$$ and $$\displaystyle {{\alpha }_{2}}$$ we find that:

$$\displaystyle {{\alpha }_{1}}=\frac{\frac{116}{3}+0.2A}{2AE} $$

and

$$\displaystyle {{\alpha }_{2}}=\frac{8}{AE} $$

The solution to the weak form can be written as:

 * {| style="width:100%" border="0"

$$ u(x)= 0.001+\frac{\frac{116}{3}+0.2A}{2AE}(x-3)-\frac{8}{AE}(x-3)^{2} $$
 * style="width:2%; padding:1px; border:2px solid #FF0000" |
 * style="width:2%; padding:1px; border:2px solid #FF0000" |
 * $$\displaystyle (Eq. 10.1) $$
 * style= |
 * }

Checking if equilibrium in the strong form is satisfied
Substituted into the equations:

$$ \frac{d}{dx} \left( AE \frac{du}{dx} \right) + 2x = 0 $$

Yields the following:

$$\displaystyle {2x-16=0}$$

which does not satisfy.

Checking if the natural boundary condition is satisfied
The following equation can be used:

$$ \sigma \left(1 \right) = \left(E \frac{du}{dx} \right)_{x=1} = 0.1 $$

title: User:Eml5526.sp11.team1.adam/HW3


text:
Talk:German vocabulary/Verbs

Is there anyway to create audio files for learning language? I've seen other sights that teach through auditory and reading.

Thanks

title: Talk:German vocabulary/Verbs


text:
User talk:Egm6321.f10.try

 Hello Egm6321.f10.try, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. All users are expected to abide by our Privacy policy, Civility policy, and the Terms of Use while at Wikiversity.

To get started, you may

 * Take a guided tour and learn to edit.
 * Visit a (kind of) random project.
 * Browse Wikiversity, or visit a portal corresponding to your educational level: pre-school, primary, secondary, tertiary, non-formal education.
 * Find out about research activities on Wikiversity.
 * Explore Wikiversity with the links to your left.

 * Read an introduction for teachers and find out how to write an educational resource for Wikiversity.
 * Give feedback about your initial observations
 * Discuss Wikiversity issues or ask questions at the colloquium.
 * Chat with other Wikiversitans on #wikiversity-en.
 * Follow Wikiversity on twitter (http://twitter.com/Wikiversity) and identi.ca (http://identi.ca/group/wikiversity).

You don't need to be an educator to edit. You only need to be bold to contribute and to experiment with the sandbox or your userpage. See you around Wikiversity! --Ottava Rima (talk) 17:27, 15 February 2011 (UTC)

title: User talk:Egm6321.f10.try


text:
User talk:Eml5526.s11.team7.Srilalithkumar

 Hello Eml5526.s11.team7.Srilalithkumar, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. All users are expected to abide by our Privacy policy, Civility policy, and the Terms of Use while at Wikiversity.

To get started, you may

 * Take a guided tour and learn to edit.
 * Visit a (kind of) random project.
 * Browse Wikiversity, or visit a portal corresponding to your educational level: pre-school, primary, secondary, tertiary, non-formal education.
 * Find out about research activities on Wikiversity.
 * Explore Wikiversity with the links to your left.

 * Read an introduction for teachers and find out how to write an educational resource for Wikiversity.
 * Give feedback about your initial observations
 * Discuss Wikiversity issues or ask questions at the colloquium.
 * Chat with other Wikiversitans on #wikiversity-en.
 * Follow Wikiversity on twitter (http://twitter.com/Wikiversity) and identi.ca (http://identi.ca/group/wikiversity).

You don't need to be an educator to edit. You only need to be bold to contribute and to experiment with the sandbox or your userpage. See you around Wikiversity! --Ottava Rima (talk) 17:27, 15 February 2011 (UTC)


text:
User:Eml5526.s11.team3.sahin/Homework 3

=Problem3.9 Linear Trial Solution of Weak Form =

Problem Statement
Refer to lecture notes 17.2

This problem is extracted Problem 3.3 from the textbook of Fish J., and Belytschko T.,

Given
Problem 3.1 given in Fish and Belytschko

The strong form is

The weak form is

Find
Consider a trial (candidate) solution of the form $$u\left(x\right)=\alpha_0+ \alpha_1(x-3)$$ and a weight function of the same form.

Part 1 Obtain a solution to the weak form in Problem 3.1.

Part 2 Check the equilibrium equation in the strong form in Problem 3.1; is it satisfied?

Part 3 Check the natural boundary condition; is it satisfied?

Part 1
The trial solutions $$u\left(x\right)$$ must satisfy the essential boundary condition $$u\left(x=3\right)= 0.001$$ so Therefore, it is weight function $$w\left(x=3\right)= 0$$ as the weight function must vanish on the essential boundaries

To find a trial solution, we need to put Eq 9.3 and Eq 9.4 into the weak form Eq 9.2

Evaluating the integrals with the assumption of cross area $$ \begin{align} & \qquad A \end{align} $$ and Young’s modulus $$ \begin{align} & \qquad E \end{align} $$ are constants

and factoring out $$ \begin{align} & \qquad \beta_1 \end{align} $$ gives

As it must hold for all $$ \begin{align} & \qquad \beta_1 \end{align} $$, the term in the parentheses must vanish, so After arranging the equation above, we obtain $$ \begin{align} & \qquad \alpha_1 \end{align} $$ Substituting this result into Eq 9.3 gives linear trial solution of the weak solution,

Part 2
We know that To check the equilibrium equation in the strong form in Problem 3.1, we need to substitute Eq 9.11 into Eq 9.1a

The equilibrium equation in the strong form is not equal. Therefore, it is not satisified.

Part 3
We know that the natural boundary condition is

To check the natural boundary condition; we need to substitute Eq 9.11 into Eq 9.1b

The natural boundary condition is not equal. Therefore, it is not satisified.

title: User:Eml5526.s11.team3.sahin/Homework 3


text:
Paideia High School/Boeke, Kees

Kees Boeke

../Cosmic View/, a work covered in Paideia High School's Year One Curriculum

title: Paideia High School/Boeke, Kees


text:
Engineering Experience 4: Design a Small Solar Vehicle/Nl/Team PM7

Team RotaLux
Welkom op de wiki van Team RotaLux! We zullen deze wiki gebruiken als online procesverslag.

Gantt Chart
Gantt%20chart.xls

Plan Van Aanpak (PVA)
plan%20van%20aanpak%20%28EE4%29.docx

Samenwerkingscontract
Samenwerkingscontract_versie%202_%2824-02-2011%29.docx

Work Breakdown Structure (WBS)
WBS_TEAM7.png

Links

 * / Blog /
 * / Design rapport /
 * Website


text:
Talk:Complex socio-ecological systems/Networks

I find the networks topic VERY interesting, but I had trouble to relate it to resilience and our previous conversations. What I have read and heard on social networks makes a bit more sense since it incorporates explicit social institutions and dynamics (like the Swedish paper). Enjoy the discussion and look forward to read the summary and comments, claudia128.227.83.224 23:12, 17 February 2011 (UTC)

Barabasi et al. (Science 1999)

 * I started with Barabasi et al.'s Science paper, and I have to say I like it. There are obvious over-simplifications in their model, which the authors' point out in their concluding remarks, but the paper represents a succinct but major advancement in our understanding of networks. That growth and preferential attachment trigger the emergence of self-organization is, well, very cool. It makes sense that Poisson distributions were initially used, particularly when we consider the shapes of these distributions at low lambda, but I can see the limitation in the assumption that all the actors within the network are initially present; even in ecological systems, networks will evolve over time, with more components entering system with advancing time steps. The paper did make me think more theoretically about models, however. The authors created a model that I think had no choice but to form a power law distribution when they introduced the probability terms for vertex connectivity. It's a deterministic process, so it brings to my mind the question of whether a theory is (better) proved because a deterministic model can create a pattern as observed in nature, or whether a non-deterministic model that exhibits emergent behavior without rules is better proof of theory?

Bascompte and Jordano (Annu. Rec. Ecol. Ecol. Syst. 2007)

 * I should start by stating I really enjoyed the review. It follows from the preferential attachments described by Barabasi’s Emergent of Scaling in Random Networks (Science 1999), so I’m very glad I accidentally read that one first. I find it very interesting that the power law distributions observed in many self-organizing systems are (may?) be scaled, in this case truncated, by a decay function. I wonder if all multi-modal networks have some sort of scaler. The decay function described here is an exponential function, and there is some critical number of links where if a network approaches that critical number (i.e., the exponential decay rate approaches 1), the probability of more connected species drops off. If I am interpreting this correctly, this means that the more connectivity there is among components, the less likely there is to be yet more species with high connectivity.  This makes intuitive sense to me from niche occupation; there are only so many niches available to highly connected generalists that any system can contain. The authors lay out a number of very good arguments why interactions and species abundance cannot be random in section 4, and for why truncation occurs, where some connections are ‘forbidden’ because they simply cannot happen for phonological or morphological reasons. The power-law distribution need not be truncated only for reasons related to the preferential attachments; if a system starts out with a larger number of species to form a network, truncation also occurs.

 * To paraphrase the section on dependences and asymmetries, niches arising from the action of generalists are less susceptible to variation, and by the same token, generalists can more easily survive in abiotic (more highly variable) environments because of an inherent invariability due to several reasons. Essentially, generalists exhibit greater resilience. Yes! We knew it would come back to that. Further, mutualism confers greater nesting of networks than does consumerism/predation, which makes sense, since consumer/predation relationships are dead-end for at least one member of the interaction. However, I wish the author had expounded more on the “asymmetry may help interdependent groups of species coexist… This kind of downward loop is less common in uneven relationships because the plant could recover by relying on a generalist partner…” (pg 577). There are systems that exhibit the classic predator/prey oscillations (the classic timber wolves and snow hares) that, despite the amplitude of species abundances, have certain characteristics of stability. Both species may be generalists in some ways, but the prey definitely makes up the greatest part of the predator diet in these cases. Does the fact that the communities recover run contrary to the concept that asymmetry confers greater resilience in a network? Or, are the oscillation lags in those predator/prey relationships created by prey switching, which would mean asymmetry? We usually think of those lags being causes by differences in generation times between the two species. Or, are the networks wherein there is a predator/prey abundance oscillation like the timber wolf/snow hare example less complex, so that the usual generalist behavior of the wolf isn’t possible?

 * That phylogeny may play an important role is laid out, but not convincingly. An observation that may occur 30-50% of the time is not the same as discovering a rule that governs network behavior. That there might be secondary network controls created by phenology and other ecological factors makes sense, but the science hasn’t gotten to the point of really explaining network structure based on these factors. This brings up the question of if we don’t have any organizing rules for phenology and ecology, are species degree and abundance the correct measures for network behavior, or are the proximate measures for the true, ‘correct’ measure? Ecology is frequently hampered by figuring out the best measure for some system property.

 * The implication that generalists give networks resilience and the loss of generalists initiates a faster collapse of a network has huge implications for the way science talks about biodiversity. Policy and land management has continually focused on giving more conservation value to the rarest, most specialized species. The sole argument is that these species create biodiversity and their rarity (and general status as most-likely-to-go-extinct) is what gives them an intrinsic value above other species. The management of these species is in some (perhaps many) cases to the detriment of the stability of more generalist species and to the network they are all nested within (the management for the cape sable seaside sparrow being a clear example).

DWatts 21:58, 16 February 2011 (UTC)

I agree that conservation biology tends to manage for specialists, and that in systems terms these may not be critical to system functioning. If you look at the red list of endangered species, a large majority are from islands or otherwise have very restricted natural home ranges.

Liljeros et al. (2001) Interesting article. However, I did not understand some important concepts that the authors use. Specifically, I don't understand what is the "power law decay" and how is a scale free network different than other types of networks. flaleite 18:54, 17 February 2011 (UTC)

Power law decay is the mathematical shape of the curve that is characteristic of scale free networks, i.e. the straight line in Figure 2 a and b. One way to think of scale free networks is that a few nodes have many connections, while most nodes have fewer connections. In a random network, there would be an average number of connections and just as many nodes have above-average number of connections as have below-average number of connections, ie. a normal distribution. In scale-free networks, you have a few hubs with many connections.

General questions
1. What is the significance of the observation that widely divergent types of networks (WWW, social, cellular) have similar structural properties?

2. Several of the papers look at the structure of networks at one point in time (static). The Palla et al paper looks at how network structure changes over time. Is this an important advance? What are the methodological challenges to such dynamic analysis, and how can they be overcome?

3. How do human and ecological networks interconnect?

4. What characteristics of their human and/or ecological networks makes systems more resilient?

Note about tomorrow's seminar
We will talk about the above questions and points brought forth by Danielle and Flavia, and hopefully others if they should find the time to do so. I would also like to plumb the depths of question 3 by demonstrating the difference between whole networks and personal networks. All of the readings this week describe whole networks, but one difference between social and ecological networks is clearly the scope of the personal (egocentric) network. You cannot, at least with modern technology, ask a hummingbird how many flowers it pollinates, not to mention the specific attributes of said flower. You can do that with humans. Please also read the short primer on SNA that Allison Hopkins prepared.~Sam


text:
Engineering Experience 4: Design a Small Solar Vehicle/Nl/Team PM7/Blog

15-02-2011
Vandaag zijn de belangrijkste documenten tegen de deadline van vrijdag opgesteld in groep. De WBS wordt verder uitgewerkt door Simon. Wouter Vrancken werkt het plan van aanpak verder uit. Frederic zorgt voor het logo en het samenwerkingscontract. De taken van de Gantt Chart zijn opgesteld en hebben een tijdsquota toegedeeld gekregen.

Verder is er nog beslist om met dropbox te werken voor de bestanden te synchroniseren.

De volgende taken zijn verdeeld:

De verantwoordelijke voor het aanvullen van de blog zal aangeduid worden op wekelijkse basis. Er is ook gekozen om zonder team-leider te werken, tenzij blijkt dat dit toch nuttig is. In dat geval wordt deze later gekozen.

Volgende vergadering zal donderdag zijn. Dan worden te taken van de Gantt Chart verdeeld.

17-02-2011
De documenten zijn verder afgewerkt. De WBS en de Gantt Chart zijn op elkaar afgestemd. Het plan van aanpak is afgewerkt.

Iedereen kijkt de documenten nog eens na. Wim zal om 17.00 alle documenten via Toledo insturen.

22-02-2011
De eerste brainstorming over het ontwerp van het zonnewagentje werd gehouden.

Na feedback van de assistent werden de Gantt Chart en de samenwerkingscontract aangepast. De WBS wordt aangepast naar de Gantt Chart door Simon.

De volgende vergadering zal donderdag zijn.

24-02-2011
De laatste aanpassingen van de Gantt Chart en het samenwerkingscontract werden besproken. Simon maakt de WBS nog af.

Vervolgens werd er over de structuur van het frame van de zonnewagen gebrainstormt. Hier zijn een 4 tal voorstellen naar voor gekomen, waaronder 2 die door Wim uitgewerkt zullen worden in Solid Edge. Deze worden ook door hem gesimuleerd om de belasting in te schatten.

De taken worden verdeeld.
 * Gewricht bevestiging : Wouter H.
 * Opzoeken mogelijkheden van lagers : Jan
 * Opzoeken materialen voor body : Peter, Wouter V
 * Wrijvingsweerstanden voor assen opzoeken : Jan
 * Simulatie spanningen in frame : Wim
 * Berekeningen transmissie : iedereen

01-03-2011
Er werd verder gediscussieerd over het frame van de zonnewagen. Op basis van de vorige ontwerpen werden verbeteringen aangebracht.
 * Wim zal het nieuwe ontwerp terug uitwerken.
 * De berekeningen voor de overbrengingen moeten nog verfijnd worden. Peter, Jan en Simon gingen hier naar kijken.
 * Simon zal de laatste aanvullingen aan de WBS doen en beginnen aan het Sankey diagram.
 * Frederic zal opzoeken welke opties we hebben voor de wielen

08-03-2011
Het werk van de voorbije week werd besproken.

De berekening voor de overbrenging werden vergeleken. De berekeningen werden gedaan op de door de docenten voorgestelde manier door Peter. Wim heeft het op een andere manier berekend. Na het gelijk stellen van de parameters, werd ongeveer de zelfde uitkomst bekomen. De oplossingen zullen nog vergeleken worden met de oplossing in Simulink.

Simon heeft de verliezen voor het Sankey diagram berekend. Na een paar vragen heeft hij deze verder aangevuld zodat het diagram gemaakt kan worden.

De verschillende mogelijkheden voor de wielen werden besproken. De wielen zullen vermoedelijk zelf gemaakt worden uit plexiglas. Als alternatief zijn er wel al voorgemaakte wielen opgezocht.

Bij het ontwerp werd besloten na overleg met de docent dat zelfsturende voorwielen weinig nut hadden. Dit zal vervangen worden door wieltjes die de wagen in zijn geheel geleiden langs de rail.

De taken voor komende week worden verdeelt:
 * Jan en Frederic : De simulatie in Simulink
 * Peter : Overbrenging verder uitwerken en beschrijven
 * Wim : Het overbrengingsmechanisme uitwerken
 * Simon : Informatie over het zonlicht en de zonnepanelen afwerken en het Sankey diagram afwerken
 * Wouter en Wouter : Beginnen aan het verslag

15-03-2011
Het ontwerp begint vaste vorm te krijgen. Enkel het overbrengingsmechanisme moet nog met de correcte overbrengingen op de juiste plaats geplaatst worden. Hiervoor wordt er echter gewacht tot de resultaten van Simulink.

De parameters (wiel diameter, rolweerstandscoëfficient,...) zijn voor een laatste keer overlopen zodat de berekeningen voor de overbreningsverhouding (manueel, maple) en het Sankey diagram correct gebeuren. De manuele berekening is nog een laatste keer bijgestuurd, maar het resultaat blijft onveranderd. In de grafiek gegenereerd door de maple simulatie zat er een vreemde buiging vanaf de helling van de race. Deze is echter te verklaren doordat de wagen vanaf dat ogenblik niet meer op het ideale toerental zit, maar er boven. De wagen zal dan volgens een dalende parabool naar zijn nieuw optimaal toerental gaan.

De Simulink simulatie is de voorbije week niet opgeschoten doordat Jan ziek was. De komende week zal dit echter ingehaald worden.

Verder staat het verslag al vrij ver. Het zijn nog vooral de berekeningen die toegevoegd moeten worden.

 * De komende week zal dus de simulink simulatie verder afgewerkt worden door Frederic en Jan.
 * Simon werkt het Sankey diagram af.
 * Wim en Peter voegen de uitleg over hun berekeningen toe aan het verslag.
 * Wouter werkt het schema voor de elektronica voor het schakelmechanisme uit voor het verslag.
 * Wim schrijft de uitleg over de elektronica van het schakelmechanisme.
 * Jan berekent de normaalkrachten die de tandwielen zullen veroorzaken om te zien of we kogellagers nodig hebben of niet voor de oeverbrenging.

23-03-2011
Bij de docent kregen we te horen dat we goed op schema zaten. Enkel Simulink moet nog afgewerkt worden. Jan en Frederik zien dit echter zitten, dus er is geen probleem.

Het document dat we hadden samengesteld was echter niet de bedoeling van de opdracht. De berekeningen moeten wel in een document samengevoegd worden, maar het design rapport moet op de blog komen. Wouter en Wouter hebben dit dan ook prompt gedaan.

Wim heeft een lijst opgesteld met de benodigde onderdelen die besteld moeten worden. Zodra gecontroleerd is dat we binnen budget blijven, kunnen deze besteld worden. Voor de tandwielen wachten we nog tot we de juist gear-ratio's via Simulink bekomen hebben. Simon gaat deze week naar de Banier om te kijken voor balsa hout.

Voor we naar FabLab gaan, hebben we de gear-ratio ook nodig om de gaten in de tandwielkast correct te plaatsen. Zodra we die hebben zal Wim zo snel mogelijk het ontwerp aanpassen zodat we naar FabLab kunnen gaan.

Taken:
 * Simulink afwerken : Frederik en Jan
 * Sankey Diagram : Simon
 * Gearbox aanpassen : Wim
 * Manuele berekeningen in tekst zetten : Peter
 * In te sturen document nakijken, formatteren en insturen : Wouter V.
 * Voor balsa hout gaan kijken in de Banier : Simon

29-03-2011
De tandwielen blijken een grotere hap uit het budget te zijn dan voorzien. Het algoritme om de tandwielcombinatie samen te stellen wordt aangepast om de prijs mee te optimaliseren. Nog een paar andere aanpassingen voor de constructie worden ook toegevoegd. Het lukt uiteindelijk om een combinatie te vinden die binnen het budget blijft.

05-04-2011
Aangezien er geen grote vragen waren, werd beslist dat Wim, Peter en Jan naar het FabLab zouden gaan om de eerste delen van de zonnewagen uit te snijden met de laser-cutter. Door een aantal problemen die nog in het ontwerp opdoken, zijn we pas tegen 16.15 in het FabLab geraakt. Hierdoor is enkel de body uit balsa uitgesneden geraakt.

De elektronica voor de aansturing van de motor is ondertussen ook klaar.

06-04-2011
Jan en Peter zijn de versnellingskast gaan uitsnijden uit plexiglas.

11-04-2011
Wouter H., Wim en Jan komen samen om de zonnewagen in elkaar te steken voor zo ver mogelijk is. De body is grotendeels af. De assen zijn ook al op maat gesneden. De versnellingskast kan nog niet in elkaar gestoken worden omdat de tandwielen er nog niet zijn.

12-04-2011
Niet alle tandwielen die nodig zijn blijken beschikbaar te zijn. Wim stelt een nieuwe combinatie op die wel voorradig is.

18-04-2011
Wim gaat naar het FabLab om nieuwe onderdelen te maken voor de versnellingskast, aangezien er een nieuwe combinatie is. Hij maakt tevens een kast voor 1 overbrenging, indien het systeem met de versnelling niet zou werken.

De tandwielen zijn aangekomen.

26-04-2011
De carbon assen in de versnellingsbak geven teveel wrijving. Deze werden in groep vervangen door assen in messing. Tegen dat dit in orde was, was de testbaan wel al afgebroken zodat we die niet meer hebben kunnen testen.

03-05-2011
Aangezien de wagen nog niet met succes getest is kunnen worden, is de race wel spannend. We weten dat we meer wrijving hebben dan waar we op hadden gerekend. Tijdens de eerste race blijkt de wrijving van de 2e versnelling te hoog te zijn. Tijdens de race schakelen we dus om zodat het zonnepaneel rechtstreeks de motor aandrijft. De rest van de races hebben we in 1e versnelling gereden.

We slagen er uiteindelijk nog in om 2 keer in de poule te winnen (zei het met geluk). De eerst volgende keer hebben we echter verloren.

De overgebleven en onafgewerkte taken worden herverdeeld.
 * technische tekening : Jan
 * berekeningen as : Wouter en Wouter
 * case 2 : Sankey : Frederik en Simon
 * proces rapport : Wim
 * enterprising : Peter
 * website : Wim

10-05-11
De taken die nog afgewerkt moeten worden:
 * processverslag : Wim, Frederic
 * enterprising afwerken : Peter, Frederic
 * technisch tekeningen : Jan
 * sankey rolweerstand : Simon
 * sankey solarteam : Simon
 * website : Wim
 * sterkteleer : Wouter, Wouter


title: File:Fe1.s11.mtg19.djvu


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Games/Hungry Dinosaurs

hungry dinosaurs is a snes game in which you eat eggs.the green eggs are your dino eggs and eat the cpu eggs to win.

Learn fun dinosaur data featured in Jim Henson's "Dinosaur Train" television show with Dino Facts Buddy! Buddy says over 120 phrases, while encouraging kids to play games using their train tickets for extra learning fun. The Dino Facts Buddy figure comes moulded in a train conductor uniform and features a large watch face on Buddy's belly. Also included are 15 unique dino information tickets, which can be inserted into the clock and trigger different phrases and facts. The watch face can also be pressed to hear additional information about the dinosaur featured on the ticket. Age 3+ Thanks pups

title: Games/Hungry Dinosaurs


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File:Abaqus 3 6 BCs.png

Licensing
Eml5526.s11.team5.vijay

title: File:Abaqus 3 6 BCs.png


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File:Abaqus 3 6 stresses.png

Licensing
Eml5526.s11.team5.vijay

title: File:Abaqus 3 6 stresses.png


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File:Abaqus 3 6 X displacement.png

Licensing
Eml5526.s11.team5.vijay

title: File:Abaqus 3 6 X displacement.png


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File:Abaqus 3 6 Y displacement.png

Licensing
Eml5526.s11.team5.vijay

title: File:Abaqus 3 6 Y displacement.png


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User talk:JoshuaZ

 Hello JoshuaZ, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. All users are expected to abide by our Privacy policy, Civility policy, and the Terms of Use while at Wikiversity.

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You don't need to be an educator to edit. You only need to be bold to contribute and to experiment with the sandbox or your userpage. See you around Wikiversity! --Ottava Rima (talk) 20:11, 15 February 2011 (UTC)

Some removals from your talk page.
. I commented on the current situation at User talk: KillerChihuahua. If I can be of any help, or to comment, my Talk page is open, as is email. I just became active on WV IRC and it seems the admin community, small, is paralyzed. It may take some time to fix. --Abd 23:46, 17 February 2011 (UTC)

title: User talk:JoshuaZ


text: Reviewing My Semester with the FUN WITH ENGLISH 7A & 8A Textbooks/Notebooks


text:
User:Eml5526.s11.team6.tupsakhare/hwk3

=HOMEWORK 3 -Problem 3.3=

Given
Referred from - Pg 37, Reference (1)

Consider the truss shown in the following FIGURE 3.3.1(PLEASE INSERT PROBLEM STATEMENT FIG HERE)

-Nodes A and B are fixed.

-A force F = 10 N acts in the positive x- direction at node C. Coordinates of the joints are given in meters.

-Young's modulus E = 1011 Pa

-Cross sectional area for all bars, A = '''2. 10-2 m2'''

Find
a. Number the elements and nodes

b. Assemble the global stiffness and force matrix

c. Partition the system and solve for the nodal displacements

d. Compute the stresses & reactions

Number the Element and Nodes
Node and element numbering is done in the following fashion. Refer to the FIGURE 3.3.2(PLEASE INSERT NUMBERERD FIGURE HERE) as given below-

Assemble the Global Stiffness and Force Matrix
We use the Following formula Referred from - Pg 30, Reference (1) for Elemental Stiffness Matrix of each element,

$$\displaystyle (Eq. 3.1) $$

Where, $${k^{e}} = \frac{l^{e}}$$ and the superscript e denotes the element number. Now in this case as seen from the given data, A and E for all the 4 elements have same but distinct values. So we can eliminate the superscript e for A and E of each element.

Element 1

 * Element 1 goes from Node 1 to Node 3

 * Orientation : 90 degrees to the Positive X-direction, $$\phi^{(1)} =90^{o}$$ . Hence, $$cos(90^{o})=0,sin(90^{o})=1$$ and $${{l}^{(1)}}=1$$

Using Eq. 3.3.1 for Element 1,

Element 2

 * Element 2 goes from Node 2 to Node 4

 * Orientation : 90 degrees to the Positive X-direction, $$\phi^{(2)} =90^{o}$$ . Hence, $$cos(90^{o})=0,sin(90^{o})=1$$ and $${{l}^{(2)}}=1$$

Using Eq. 3.3.1 for Element 2,

Element 3

 * Element 3 goes from Node 2 to Node 3

 * Orientation : 135 degrees to the Positive X-direction, $$\phi^{(3)} =135^{o}$$ . Hence, $$cos(135^{o})=\frac{-1}{\sqrt{2}},sin(135^{o})=\frac{1}{\sqrt{2}}$$ and $$l^{(3)}=\sqrt{2}$$

Using Eq. 3.3.1 for Element 3,

Element 4

 * Element 4 goes from Node 3 to Node 4

 * Orientation : 0 degrees to the Positive X-direction,$$\phi^{(4)} =0^{o}$$, $$cos(0^{o})=1,sin(0^{o})=0$$, $$l^{(4)}=1$$,

Using Eq. 3.3.1 for Element 4,

GLOBAL STIFFNESS MATRIX
Using above Elemental Matrices, we construct the Global Stiffness Matrix for the given Truss System as follows,

FORCE MATRIX
The force matrix contains reactions and externally applied force components at various nodes. Let Rx = Reaction at node in x -direction, Ry = Reaction at node in y -direction, subscripts denote the node number Also node 3 is free to move in both x- and y- direction and is free of any external forces. And node 4 is free to move in both x- and y- direction and has an external force of 10 N applied in the x- direction as per the given data in the problem statement.

The Force Matrix is assembled as follows -

NODAL DISPLACEMENT MATRIX
The noddal displacement matrix contains displacement components at various nodes. Let ux = Displacement at node in x -direction, uy = Displacement at node in y -direction, subscripts denote the node number Nodes 1 and 2 are fixed so they have all the components of displacement as zeros (0). Also node 3 and 4 are free to move in both x- and y- direction.

The Nodal Displacement Matrix is assembled as follows -

Partition the system and solve for the Nodal Displacements.
Now, using the Global stiffness matrix (K), Force matrix (F) and the Nodal displacement matrix (d), we can write the Global System as follows,

$$\displaystyle (Eq.3.3.2) $$

As the displacements for first two nodes are prescribed, we partition the systems after four rows and columns.

System Partition
Also we use the following equation from - Pg 23, 'A first course in finite elements' - Fish & Belytschko -2007 and compare our global system with it to get the nodal reactions and elemental stresses using $$\displaystyle (Eq.3.3.2) $$ & $$\displaystyle (Eq.3.3.3)  $$ -

$$\displaystyle (Eq.3.3.3) $$

On comparison then we get the following partitioned matrices -

Nodal Displacements
We solve the following system of equations to get the nodal displacement matrix,

But $$\bar{d}_{E}$$ is a Zero Matrix, which will yield, $$d_{F}=K_{F}^{-1}.f_{F}$$ Solving using the above equation, the unknown nodal displacements are

$$\displaystyle (Eq.3.3.4) $$ -

Nodal reactions
Using the above equation the unknown reaction values are

$$\displaystyle (Eq.3.3.6) $$

Elemental Stresses
The stresses in the elements are given by the following expression from page 34 of the reference (1)

For element 1:

 * $$ cos90^{\circ} = 0,\quad sin90^{\circ}=1, $$

\mathbf{d}^{(3)}=l^{(3)}/AE\begin{bmatrix} u_{1x}\\ u_{1y}\\ u_{2x}\\ u_{2y} \end{bmatrix}, \qquad \sigma ^{(3)}=1/A\begin{bmatrix} 0 & -1 &0 &1 \end{bmatrix}\begin{bmatrix} 0\\ 0\\ 38.2843\\ 10 \end{bmatrix} = 500N/m^{2}

$$

For element 2:

 * $$ cos135^{\circ} = -0.707,\quad sin135^{\circ}=0.707, $$

\mathbf{d}^{(2)}=l^{(2)}/AE\begin{bmatrix} u_{2x}\\ u_{2y}\\ u_{3x}\\ u_{3y} \end{bmatrix}, \qquad \sigma ^{(2)}=1/A\begin{bmatrix} 0 & -1 &-0 &1 \end{bmatrix}\begin{bmatrix} 0\\ 0\\ 48.2843\\ 0 \end{bmatrix} = 0 N/m^{2}

$$

For element 3:

 * $$ cos90^{\circ} = 0,\quad sin90^{\circ}=1, $$

\mathbf{d}^{(1)}=l^{(1)}/AE\begin{bmatrix} u_{2x}\\ u_{2y}\\ u_{4x}\\ u_{4y} \end{bmatrix}, \qquad \sigma ^{(1)}=1/A\begin{bmatrix} 0.5 & -0.5 &-0.5 &0.5 \end{bmatrix}\begin{bmatrix} 0\\ 0\\ 38.2843\\ 10 \end{bmatrix} = -1000N/m^{2}

$$

For element 4:

 * $$ cos0^{\circ} = 1,\quad sin0^{\circ}=0, $$

\mathbf{d}^{(4)}=l^{(4)}/AE\begin{bmatrix} u_{3x}\\ u_{3y}\\ u_{4x}\\ u_{4y} \end{bmatrix}, \qquad \sigma ^{(4)}=1/A\begin{bmatrix} -1& 0 &1 &0 \end{bmatrix}\begin{bmatrix} 38.2843\\ 1\\ 48.2843\\ 0 \end{bmatrix} = 10/(2*10^{-2})= 500N/m^{2}

$$

title: User:Eml5526.s11.team6.tupsakhare/hwk3


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Book Reviews/From the files of Madison Finn

From the files of Madison Finn: Thanks for Nothing

From the Files of Madison Finn is very dramatic book, whereas, the main character, Madison Finn, is 12 and is around my age and I clearly understand how difficult it must be for her to select one of her parents over the other parent, basically to spend Thanksgiving with. Also, this is her first year to have Thanksgiving without her father and her parents are mad at each other about who's staying with who and Madison thinks that they are angry because of her. While Madison is choosing which parent to spend Thanksgiving with she volunteers at a local dog pound and finds out that, Dan Ginsburg, an old friend from school, who ate everyone's leftovers at lunch when they didn't want it, volunteers there too. Madison soon becomes friends with Dan, while he helps her learn what to do when your volunteering.

While Madison is volunteering at the animal clinic and deciding who to spend Thanksgiving with, she also has a extra-credit Social Studies project, The Mayflower, she had to do the with her friend, Walter “Egg” Diaz, he got his nickname because when he was younger he got hit in the face with an egg. Unfortunately, Egg gave her very little support in the beginning of the project and was late to most of their meetings about the project, which caused disagreements in their friendship.

Madison's father, Jeff, has told Madison that she could come to Texas with him and his girlfriend, Stephanie, to her family's ranch for Thanksgiving, but she did not tell her mom, Francine, about the trip, but Madison did not want to go to Texas with her dad so she plans to stay and have Thanksgiving with her mom. Also, Madison and Egg are starting to come up with great ideas for their extra-credit project, The Mayflower, and at the animal clinic, Madison became close to one of the dogs, Sugar, a schnauzer-poodle, who was abandoned on the steps of the clinic, but then while Sugar was recovering she got sick and might need surgery. Then Dan tells Madison that Sugar does not need surgery, she was just going through shock after being rescued.

Madison and Egg presented their project and Madison noticed that their project was being displayed in a display case. So she knew that she did a great job with Egg.

Thanksgiving day and Madison is staying with her mom, while her dad is in Texas having Thanksgiving with Stephanie's family.


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Teaching EFL Listening via FUN WITH ENGLISH Books/7A/New School Lesson

If you use this lesson, please share your review here.

Preface
This lesson is built almost entirely around the textbook chapter. I did this for some of early lessons, but soon I moved away from this using some textbook exercises and more activities that fit into the same topic.

Introduction
OBJECTIVE : L4 - Orientation to text, students will be able to "identify the role/relationships of the speakers."

Plan

 * 1) Warmup Conversation
 * 2) * What did you do on Sunday? & then follow up questions.
 * 3) * What do you do on the first day of school?
 * 4) * Did you remember to bring your notebooks?
 * 5) Page 2 Exercises A & B
 * 6) * Ask for volunteers to read the boy and girl parts.
 * 7) * If no volunteers, read it myself.
 * 8) * After each conversation ask the class if they are "old or new friends?" and then "why?"
 * 9) * Then, have them write "old friends" and "new friends" after each conversation.
 * 10) Page 2 Exercise C
 * 11) Page 3 Exercise A
 * 12) * Read it by myself.
 * 13) Page 3 Exercise B
 * 14) * Read it by myself.
 * 15) Page 4 Exercise B
 * 16) * Read it by myself.
 * 17) Page 5 Exercise B
 * 18) * Read it by myself.
 * 19) Name Check & Seat Assignments
 * 20) * Have all the students stand up.
 * 21) * Go through their names, and give them seats based on their number. Check to make sure all the names/pictures are correct.
 * 22) * Do this by picture and explain to them what's going on.
 * 23) Game
 * 24) * Ask if they remember what game we played the week before?
 * 25) * 2 Truths, 1 Lie - Class 4?
 * 26) * Run For Your Friends - Class 5
 * 27) * Simon Says


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