Eugenio Rosales

Juan Manuel Fuentes Rodríguez

Abel Alfonso

Fírvida Donéstevez

Dairelys García Rivas
email: dgrivas@uci.cu@www

Cuban GNU/Linux Nova Distribution for Server Computers

This article presents the novelties offered by the new version of GNU / Linux Nova distribution in its server edition, exposing the new features such as network attached storage, distributed files system, charge balance for PostgreSQL database servers and thin clients, as well as the basic features of a standard server. All these developments are obtained from the integration with the server management platform Zentyal designed to facilitate the work of the end users of the variant of this Cuban distribution.

Introduction

After Informatics Havana 2009 event, Revolution Commandant Ramiro Valdés decided to implement an edition of the GNU/Linux Nova Cuban Distribution to migrate the country servers. A server oriented operating system must maximize the conditions of ICTs use in State Central Management Organisms (OACE) under technological sovereignty, security, socio-adaptability y sustainability principles [START_REF] Fuentes | Distribución cubana de GNU/Linux: soberanía tecnológica, seguridad, criollo[END_REF]. For this reason, Nova development team releases that same year the first Cuban Server Distribution. This first version didn't count with a graphic interface to allow the administrator to easily and efficiently configure the system, so it was hard to manage the different services.

Besides, the fact that the administrator had to write directly in the configuration files might bring services errors, which often become fatal.

According to this situation, Nova team members wanted to facilitate servers management through a comfortable graphic interface, which could be also intuitive and highly reduce the occurrence of services errors on its next version.

Therefore, are proposed as objectives for this work:

• Integrate to Cuban Server Distribution a graphic interface for services management.

• Provide and develop a group of services as modules to the administration interface.

Development Methodology

OpenUP was used as software development methodology, because embraces a pragmatic and agile philosophy that centers on software development collaborative nature and allows more freedom because the model can be extended with part of other models, to face a wide variety of project types. It is a condensed process but is quite complete, with easy application to small and medium projects and easier to learn for smaller development teams. It is applied with an iterative and incremental focus inside a structured live cycle.

Management platform: As a centralized management platform was used Zentyal, a unified open source network server created for small and medium enterprises (SMBs). It can act managing network infrastructure, as gateway to Internet, managing security threats, as office server, as unified communications server or a combination of them [START_REF]Documentación de Zentyal 3.0[END_REF]. Besides, Zentyal includes a development framework to facilitate the development of new UNIX based services [START_REF]Zentyal Module Development Tutorial[END_REF]. Even with all its options Zentyal does not have some services that are necessary in new informatics environments in the country, as SAN 1 /NAS 2 infrastructure and thin clients or no-disk machines. Fundamentally to these modules has been guided the work of the product developers.

Network attached storage module: NAS is the name given to a storage technology dedicated to share the storage capacity of a computer (server) with personal computers or client servers through a network, using an optimized operating system to give access with Microsoft Common Internet File System (CIFS), NFS, FTP or TFTP protocols. NAS communications protocols are based in files, so the client requests the entire file to the server and handles it locally, that´s why they are oriented to information stored in small size and huge amount files. Using NAS provides some advantages as: capacity of sharing units, less cost, using the same network infrastructure with a simpler management. A plugin was implemented to Zentyal for adding support for implementing storage services on network via NAS, using ZFS 3 , which is a file system developed by Sun Microsystems for their operating system Solaris. It has a 128 bits capacity (264 times a 64 bits file system capacity) [START_REF]Zettabyte File System[END_REF]. For its implementation was necessary to add native support to Nova kernel.

Distributed files system module:

Another product oriented to storage servers is the files systems cluster module, that allows to have multiple disks, even computers together in a cluster that is accessed through the network by client computers as a simple shared resource [START_REF] Montero | Clúster de servidores web para aplicaciones desarrolladas sobre software libre que soportan altos niveles de concurrencia[END_REF]. This method is even cheaper than NAS as thus can be implemented with outdated hardware already present in the country's institutions.

PostgreSQL charge balance module:

PostgreSQL is one of the free databases managers most used generally in the world and particularly in Cuba. It's common for a poor network infrastructure not to have powerful machines on which to mount this manager to be robust and reliable at all times. Nova Server provides an interface for PostgreSQL charge balancing that interacts directly with pgpool-II tool [START_REF] Sabater | Replicación y alta disponibilidad de postgreSQL con pgpool-II[END_REF] and allows reducing the connection overcharge, and improve overall system performance; managing multiple PostgreSQL servers and reducing charge on them.

Thin clients suite module: Nova has several ways of configuring thin clients, from the tedious manual configuration of all necessary services, to Osplugger: a native development that allows administration and configuration of most of this service related components. This tool, integrated with Zentyal, using LTSP module will allow Nova Server to gradually become the ideal suite for thin clients environments in the country, allowing Cuban operating system to be inserted gradually on network environments dominated nowadays by Windows Server or even other GNU / Linux distributions.

Antivirus module: Zentyal by default uses ClamAV 4 antivirus, which is an antivirus toolkit specifically designed to scan e-mail attachments in a MTA 5 . It has been said by MIC that "For virus protection, antivirus programs produced in the country will be used, or other officially approved for its use in the country, up to date."

According to this, it has been developed a module for managing files and email through SavUnix 6 .

Known Results: Once made and analyzed the proposed solution, GNU / Linux Nova Cuban Server Distribution was developed, and its integration with Zentyal, has made a GUI for telematic services management and to get a native product capable of deciding on it. It will be helpful for Cuban SMBs in the free software migration process that takes place in the country, as for an advanced alternative for network managers for convenient, simple and intuitive work. Being developed in Cuba contributes to its technological sovereignty, because it was possible to incorporate Nova Server's team as members and contributors of Zentyal development international community. It has also been established a direct and effective communication with the developers of the Cuban company Segurmatica Antivirus, managing to incorporate to the solution, a Cuban anti-virus, maintaining a constant and effective collaboration between both parties. This way not only has been possible to maintain a close relationship of collaborative development, but to give visibility to the project in the international framework. It has been possible to deploy thin clients on a smaller scale (10) in the University of Informatics Sciences (UCI) library and on a larger scale (64), in the MIC, working properly. Below is a table that reflect aspects that give validity to using Zentyal in Nova.

Conclusions

Nova Server is a project that has been gaining strength and is destined to be one of the products with more acceptance from Nova family, given its high levels of adaptation to the requirements of the Cuban enterprise informatization. The development of new modules for its management system not only allows new features, but after reviewing the knowledge gained in its development, people can think of a sovereign software where decisional capacity and response times to errors are minimized, including compensation of this knowledge to the international community that can gain merits and recognition for Nova.

Table 1 .

 1 Tool comparison

		Windows	Webmin	YaST	Zentyal
	Operating system	Windows	GNU/Linux	openSUSE	Nova
	License	CAL	BSD	GPL	GPL
	Usage easiness	High	Low	Medium	High
	Executionmode	Local	Local	Local	Local
	Security	Low	Medium	High	High


Tetsuo Noda
email: nodat@soc.shimane-u.ac.jp

Terutaka Tansho
email: tansho@riko.shimane-u.ac.jp

A Study of the Effect on Business Growth by Utilization and Contribution of Open Source Software in Japanese IT Companies

To analyze how OSS effects business growth both through simple use and by deeper engagement as a stakeholder in OSS community, we did questionnaire research to Japanese IT companies in 2012 and 2013. We analyze the progress of utilization and contribution of OSS, and the impact on business growth indicators by them.

Introduction

It has become commonplace for business enterprises to use OSS in their business activities. As a result, utilization of OSS only for cost reduction has become no longer a factor of obtaining the competitive advantages for them. The logic we understand as framing this such engagement is that the competitive edge that comes from technical advantages delivered by using OSS, and -using the same logic -it is therefore indispensable for them to contribute or participate in the development process of OSS. To verify this hypothesis, we questioned utilization and contribution of OSS, and business indicators to Japanese IT companies in 2012 and 2013.

Correlation between Utilization and Contribution of OSS

Table 1 .

 1 Correlations between utilization and contribution of OSSSurvey Results in 2012 (n=191) Survey Results in 2013 (n=146) Spearman's rank correlation coefficient ** 1% level of significance, * 5% level of significanceFirst, the correlations between utilization and contribution of companies in many OSS technology types are not shown in both years. As for these OSS technologies, Japanese IT companies are still "free riders." On another front, the correlation between Ruby and Ruby on Rails in this context is shown. And those of Other Languages between Apache and Databases technologies are also shown.

	utilization contribution	Linux	Apache	Databases Ruby	O.L.	RoR	contribution utilization	Linux	Apache	Databases Ruby	O.L.	RoR
	Linux	.136	-.002	.004	.128	.083	.110	Linux	.062	.009	-.013	.080	.032	.037
	Apache	.151	.135	.054	.149	.125	.111	Apache	.072	.048	.012	.095	.013	.033
	Databases Ruby Other Languages	.050 .031 .144	-.016 -.013 .161 *	.052 .007 .189 *	.132 .324 ** .099	.098 .114 .272 **	.105 .351 ** .140	Databases Ruby Other Languages	.136 .098 .139	.086 .057 .114	.106 .044 .144	.083 .461 ** .208*	.082 .164 .217 *	.043 .320 ** .257**
	Ruby on Rails	.087	.086	.065	.331 **	.159	.420 **	Ruby on Rails	.180 *	.141	.129	.400 **	.239 *	.343 **

Effect on Business growth by OSS utilization and contribution

From the survey result in 2012, the subsequent period prospect of sales growth rate is impacted by utilization of OSS. At the same time, the survey result in 2013 shows that the present period of sales growth rate is impacted. It turns out that the sales growth rate prediction by utilization of OSS expected from the reference fiscal year appears in the following fiscal year. The contribution of OSS communities has an insignificant effect on sales growth. But he survey result in 2013 shows that the prospect of employee number's growth rate (subsequent period) is impacted by contribution of OSS. Japanese IT companies tend to expect direct sales growth by OSS practical use, and they might also expect contribution to the development process of OSS leads to the increase of employee, personnel training, and personnel adoption.


Eng Edilberto Blez Deroncelé

MSc Pierra Allan

Fuentes

MSc Caridad Dayana

Tejera Hernández

Eng Haniel

Cáceres Navarro

Eng Abel

Alfonso Fírvida Donestévez

Eng Michel Evaristo

Febles Parker
email: mfparker@uci.cu

USB device management in GNU/Linux Systems

Protecting the access to USB ports has the same priority for information security than firewalls and antivirus software. Nowadays there are some tools that allow us to monitor and regulate the access to USB devices, but all of them are distributed under proprietary licenses. This work presents an application that solves the mentioned problem: ¿How controlling the access to USB mass storage devices in GNU/Linux Operating Systems?

Introduction

One of the most important advantages of devices guided by USB industrial standard is the access easiness to every kind of computer that provides its usage. Theoretically this can be an advantage to the enterprises, except for the fact that concepts "security" and "access" are completely opposite in the Security Information area.

After the creation of the Universal Serial Bus, at the beginning of 90s, the development of technologies around of USB devices has been constantly evolving. The most recently versions of this kind of devices have increase its storage capacity, which implies the improvement of its performance and the decrease of its height.

So, with USB devices user can count with an easy means of transport, to store information while maintaining its availability. Anyway, the easy access of these devices to computers and the sensitivity of the information handled by them, can bring a set of disadvantages and vulnerabilities, both for end users and businesses. Deliberate or accidental users can:  Remove critical data.  Exhibit confidential information.  Introduce malicious code that can affect the entire corporate network.  Transferring inappropriate or offensive hardware company material.  Make personal copies of company information and intellectual property.  Connect portable devices and consequently distract workers during working hours.

In an attempt to control these threats, companies began to prohibit use in workstations of USB devices for personal use. However, practice indicates that trusting on voluntary compliance by users is not enough. The best way to monitor and regulate access, and maintain control of these devices has been by placing technological barriers.

Migration to open source technologies and open standards in the companies has found barriers in this regard. The protection of information and the USB ports of computers was made in companies using proprietary applications like "MyUSBOnly", "GFI EndPointSecurity" and others. How it has not been found a similar application in the field of free software. This research persues the goal of present a tool similar behavior but to enviroments GNU/Linux. The version we have today in GNU/Linux specifically Cuban GNU/Linux is the Unix Smart Blocker for Universal Serial Bus, USB 2 1.0 tool, which is the application shown in this paper.

Contents

A technological barrier to the uncontrolled use of USB devices in a company is the solution proposed in this research. The application USB 2 1.0 will allow controlling and restricting the use of USB devices on computers that use GNU operating systems.

The code of the application currently in development can be located https://github.com/editoblezd/usbsecurity-dev

Methodology

During this research were used scientific methods: analysis-synthesis, historical analysis and experimental one, which allow us the foundations for the development of the application.

By Analysis-synthesis method were studied the most used technologies nowadays to identify its main features; which were the basis for the design and implementation of the first version of USB 2 1.0. Some of them were: control of USB ports via a database with authorized devices and alerting users to the authorization or not of new devices.

Historical analysis method allows us to study the evolution of this kind of application and as a result, to identify the need that existed in the distributions of GNU/Linux for a tool to control access to USB storage devices. University of Informatics Sciences (UCI) users and the free software community were the main samples for this research.

The experimental method allowed testing the correction of the functionalities implemented with main samples.

The development of the application was useful to the user community GNU/Linux, because is an alternative to protect users from data loss, data robbery, or other negative consequences of the use of USB mass storage devices. Once developed the tool, safety levels in environments GNU increased and hence the users' trust in free operating systems.

Results and discussion

Some of the tools used to control USB devices are: USB Blocker, Device Lock, GFI EndPoint, MyUSBOnly, Endpoint Protector 4 and USB Over Network Server; but most used are the first five.

The freeware software USB Blocker created by NetWrix Corporation, is an interesting centralized locker that allows controlling access to the computers on a network using enabled USB devices. It locks different kinds of mass storage devices, such as removable hard disks, iPods and others [START_REF] José | eficiente bloqueador de acceso USB para red[END_REF].

USB Blocker can control the access of authorized or unauthorized devices, functioning as a mean of protecting security control malware, viruses or loss of sensitive in-formation for the corporate network where used. Unlike other solutions, does not require installation on each computer on the network, functioning as an integral network control system. Its main disadvantage is that in addition to be proprietary is conceived only for Windows systems.

Device Lock allows defining which users can access to specific ports and devices on a computer. Its management can be made using group policies in an Active Directory domain, creating a console for administration [START_REF] Pyme | control total sobre los USB en la empresa[END_REF]. But, like USB Blocker, is available only for Windows platforms NT/2000/XP/Vista/7 and Windows Server 2003/ 2008, and is proprietary. Among the main features that can be managed with Device Lock are: users or groups access control, a whitelist of devices regardless of where they connect, ports auditing and integration of TrueCrypt and PGP Whole Disk encryption.

GFI EndPoint is another powerful tool that has among its main functions: groupbased protection control, granular access control , support for various kinds of portable devices, logging user activity in SQL Server , the agent protection with increased security, control of portable storage with Unicode support and the event log [START_REF]Feature[END_REF].

MyUSBOnly provides the least amount of functionalities, but it is the most used by companies and end users. Allows quick and easy way to protect USB ports and set a password to access them. Requires Microsoft Windows 2000, XP, 2003, Vista, 7 or 2008 [START_REF] Myusbonly | SYSTEM REQUIREMENTS[END_REF] as operating system.

All these applications are developed for Microsoft Windows operating systems which makes slower the migration process of companies to free software.

Currently, the tool Endpoint Protector 4, brand development some guidelines for tool described in this paper. Although this tool solves the problem posed in this investigation, but it is not distributed under GPL license, which becomes a obstacle for GNU environments.

The Endpoint Protector 4 Web administration and reporting console offers a complete overview of the device activity on your computers, whether you work with Windows, Mac or Linux platforms. The enterprise will be able to define access policies per user/computer/device and authorize devices for certain user or user groups. Thus, the company will stay productive while maintaining control over the device fleet use. [START_REF][END_REF] The tool presented in this paper aims to be fast, efficient and simple. It has good acceptance by Cuban users and is compatible with GNU/Linux systems and is distributed under GPLv3.0 License. The application libraries are distributed under the LGPL v3.0 license. USB 2 1.0 increases safety levels required in Cuba and its usage can be included in the safety regulations must have any cuban institution under Resolution No.127/2007 [6 ].

Development Technology

For the development of application was used C, as the programming language, using glibc libraries and gtk +-2.0 for interfaces. Was used vim as Integrated Development Environment and to store information in the database is used squlite3 library.

USB 2 1.0 1.0 has incorporated a default graphical user interface in text mode. The tool, developed as a library, provides the necessary tools so you can build a graphical interface for different environments.

Recognition of the device in the computer

Udev is the device manager for the Linux kernel. Essentially this device handles devices nodes that are regularly can be found in /dev directory. This is the successor of devfs and hotplug, so it handles /dev directory and all actions taken in user space when devices are added and subtracted in the computer.

How udev by default is active for all systems that use the version 2.6.x of the kernel or upper, is used to recognize devices in the system. In the process of connecting or disconnecting a device to the system, udevd demon executed by udev receives a uevent released by kernel indicating that an action of adding or disconnecting a device has been captured.

Sysfs is a virtual file system that provides the Linux kernel v2.6. Exports information about devices and drivers from the kernel device model to userspace and also allows to set its parameters. When a device is attached to the system, in addition to the information stored by udev in its database, the kernel enclosed information necessary for its work in the virtual/sys directory.

Among the possibilities of udev are its rules. These rules have a syntax that allows both read attributes of a device and change others, depending on the type of attribute.

A set of rules decide what action needs to be done with obtained data. What rule will do, probably, will be to name the device, to create the appropriate device file, and run the program that has been set to activate the device.

Rules can associate a unique name to a device, but can also call an external program to give more information about the device; so that can obtained a more specific name. Most of the rules that come by default in the system are stored in /lib/udev/rules.d/.

By using these rules is performed a device recognition and are selected only storage devices to manage access to the system. The attributes that are granted to allow uniquely identify devices and thus can control them.

The device recognition is an important phase in its access control process system to the system. If this action is performed successfully can be achieved the authorization of only those devices that have been previously authorized by the administrator or superuser.

The rule would look like this:

#Regla usbsecurity1.0 ACTION=="remove",GOTO="disk_usb_end" SUBSYSTEM!="block", GOTO="disk_usb_end" # Para importar información de los padres. ENV{DEVTYPE}=="partition",IMPORT{parent}="ID_*" #Ignorar discos floppy KERNEL=="fd*",ENV{UDISKS_PRESENTATION_HIDE}="1" KERNEL=="sd*[!0-9]|sr*",ENV{ID_SERIAL}!="?*",SUBSYSTEMS=="usb",IMPORT{pr ogram}="usb_id --export %p" #Ejecutar un programa al conectar dispositivos USB. KERNEL=="sd?",ACTION=="add",ENV{ID_BUS}=="usb",SUBSY STEM=="block",SUBSYSTEMS=="usb",PROGRAM!="/usr/sbin/usb security /dev/%k", ENV{UDISKS_PRESENTATION_HIDE}="1" ENV{DEVTYPE}=="disk", KERNEL!="sd*|sr*", ATTR{removable}=="1", GOTO="disk_usb_end" LABEL="disk_usb_end"

As can be seen when a storage device is connected, this is the action is ACTION = "add", the "usbclient" program is executed passing the name of the device node recognized by the kernel as argument. This program performs device access check tasks and returns true or false depending on whether the device is not authorized to access the computer or if it is respectively. In case of been authorized, the rule does not reach its end and the device goes through the normal connection and removes process. Otherwise does not allow accessing the computer by removing the device node so that can not do access device to the system even with the root password.

Verification of access permission.

For verification of system access, is necessary to know several device attributes such as serial number. For getting such attributes are used programs already offered by udev as usb_id which exports device information to the udev environment variables, in this case specifically are exported the attributes with udev format and the order:

IMPORT{program}="usb_id --export %p", escrita en la regla de udev si es que otro programa no la han importado ya. La sección que comprende esta orden ejecuta de forma general: # USB devices use their own serial number KERNEL=="sd*[!0-9]|sr*", ENV{ID_SERIAL}!="?*",SUBSYSTEMS=="usb", IMPORT{program}="usb_id --export %p" Once imported to this information can access this in the written program usbsecurity.c using function: g_getenv(ENV_SERIAL), which returns the serial number of the device. In addition is needed to know what type of device it is, this is if it is a partition or a disk. That is obtained through the g_getenv( ENV_DEVTYPE) function which reads this environment variable.

Once imported this information, application checks if the serial device is already registered in its database, thus deciding the return value. This return value depends on whether the device is finally shown to the user or not.

Managing devices

The application has a graphical user interface with which the devices are managed, a new device can be added to the database, can be deleted and modified its identifier too. By default when a device is connected and it is not authorized is recorded in the database but is not authorized. In the ID field is set by default Not allowed, which means that although this is not registered can not access the system until you can not change the ID.

Adding a device

To add a device must be connected to the computer and if it is not authorized, will show the user a notification to let him know the current state of the device. To authorize a system, administrator must access the management interface for the device approval process.

In this interface the administrator must change the default identifier that takes the device, to authorize it. If, however, you will not change this ID after log all devices that still have the original identifier will be deleted from the database. Once the device is authorized it will be mounted automatically in the file system of the operating system. Once the device is authorized, is launched to the user a notification informing the changes.

Sorting an authorized device identifier

The process of modifying the device ID, performs in the same way that of adding a device to the system. The difference lies in that the device is already authorized in the system and as a first step the administrator or super user had to change the default identifier.

Removing a Device

To remove the device, simply must be selected in the administration interface and click the button to the elimination. After acceptance of the confirmation message, the device will be removed from the database and will automatically unauthorized use in the system.

Activity Logging

Internally the system, in addition to the information displayed in the Admin GUI, other attributes in system logs. When any activity, both connection authorization and de-authorization is performed, is stored information relating to this as time, date, and user who performed the action and the serial number of the device. This helps finding events if an abnormality arises, to find the root of the problem. It is important to note that how this valuable information is stored, it can be known information about any device that attempts performing any action, which ensures an extra level of security, in this case the detection.

Conclusions

USB Unix Smart Blocker 1.0 provides another point of support for the growing process of migration to open source platforms. With this version of the product the administrators of workstations will be able to control the access of USB devices, increasing levels of security for enterprises. From the economic point of view, for a country like Cuba, paying for software licenses over 600,000 workstations migration process is a rather high figure. USB Unix Smart Blocker 1.0 is distributed under GPL license, besides being a valueadded product to the Cuban distribution of GNU / Linux Nova, used as the main distribution in the migration process of the country. The architecture used in the development of the application allows for future expansion and scalability of it. What provides companies with a tool adaptable to the conditions they need.

USB 2 1.0 has arrived as a free alternative in GNU/Linux systems to monitor and control USB devices.

Recommendations

It is recommended:

1. To expand the number of devices that are supported by this tool, to have control of these.

2.

To use this tool to protect your USB ports, measure as important as installing a firewall and antivirus program maintenance. USB 2 1.0 makes easy the protection of this critical part of your PC or laptop.


Cleide L B Possamai
email: cleide@inf.ufpr.br

Diego Pasqualin
email: dpasqualin@inf.ufpr.br

Daniel Weingaertner
email: danielw@inf.ufpr.br

Eduardo Todt
email: todt@inf.ufpr.br

Marcos A Castilho
email: marcos@inf.ufpr.br

Luis C E De Bona

Eduardo C De Almeida
email: eduardo@inf.ufpr.br

PROINFODATA: Monitoring a Large Park of Computational Laboratories

This paper briefly presents a model for monitoring a large, heterogeneous and geographically scattered computer park. The data collection is performed by a software agent. The collected data are sent to the central server over the Internet, and stored by the storage system. An on-line portal makes up the visualization system, featuring charts, reports, and other tools for assessing the state of the park. This system is currently monitoring circa 150,000 machines.

Introduction

Digital inclusion is a major challenge of modern society. The Brazilian government has made large investments in equipment and infrastructure to grant access to information and communication technologies. With the success of installing laboratories in a large territory, arises another challenge: to monitor such giant park, ensuring that all investment meets its social and economic objectives. Aiming to solve this problem, it is necessary to define a model and implementation of IT solutions that enable the monitoring, in an easy and transparent way.

System Description

The proposed system has three independent modules: i ) Data Collection System; ii ) Data Storage System; and iii ) Visualization System.

Data Collection

The collection module gathers data from computers spread over the country. A client-server scheme is adopted. The agent implements the client Web Service, collecting the information from the source machine and storing it locally in XML format, connecting to the central server and sending the data. The central server collects this data from all agents, storing them in a database and also providing authentication methods and secure connections.

The implementation of the Web Service client was done in C due to performance issues and minimization of the number of packages that must be sent, since in many regions of Brazil the quality of internet connection is poor. The Web Service server is an Apache Axis because it contains the base protocols and safety extensions implemented. Due to the large amount of machines, the server does not maintain the connection states of the clients.

The computers are distributed by the ministry of education with Linux Educational (http://linuxeducacional.c3sl.ufpr.br/), with the monitoring agent installed. Since schools may install another operating system or distribution, the agent has been designed to work across major operating systems and distributions.

In Linux-based systems, data collection was developed using Shell Script language, whereas on machines with Windows operating system, data collection was developed using the Python programming language. In order prevent the server from being overloaded, each agent sends the inventory at random times, distributing the total load along all the day. The data collected by the agent are the identifier code of schools, type of machine, network usage and inventory.

Storage System

This module uses a typical storage architecture for large-scale data (Data Warehouse -DW), oriented to read operations that favors the analysis of large volumes of data. A DW architecture consists of three stages: loading, storing and reading data. This division increases the overall performance of the system where different operations (i.e. writing, reading) are directed to different structures. This also adds versatility, so that it is possible to replace one technology by another without impact on the rest of the system, e.g., through the use of new technologies that may further improve data read performance, e.g., MapReduce [START_REF] Lämmel | Google's mapreduce programming model -revisited[END_REF], and C-Store [START_REF] Stonebraker | C-store: A column-oriented dbms[END_REF].

The three stages are divided in two separate databases: a temporary data database (Staging Area) and a database of historical records (Data Warehouse).

The Staging Area is a database that receives connections from the web server to write data collected during the day. This database has its data deleted after the consolidation of daily data held by DW. The Data Warehouse is a database responsible for storing all historical data. DW reads and consolidates the data from the staging area, once a day, starting at predefined times.

The Data Mart is a subset of DW, summarized and optimized for reading operations [START_REF]Designing data marts for data warehouses[END_REF]. These subsets are determined according to the interest of the consultations. The goal of DMs is to increase the overall performance by creating specific structures for each universe of reports, such as inventory, availability, audit, and network usage. The database was implemented using technology based on open source, in our case, with the management database system (RDBMS) PostgreSQL (postgresql.org). What makes Data Warehouse a high performance system is that the information is joined in a database in a dimensional way [START_REF] Bellatreche | Dimension table driven approach to referential partition relational data warehouses[END_REF], reducing the use of join operations in queries.

Visualization System

The visualization system is composed of a web portal, which is in turn subdivided into a server and a client. The web server is responsible for receiving and processing requests, fetching the requested data from the database (Data Marts), and returning the report or graph to the client. The client application is the web portal itself, viewed through a browser and responsible for presenting an interface that facilitates the search and visualization monitored data.

The proposed model is based on a multilevel grouping of monitored machines, for example, arranged by geographic location and institution. The visualization system has in the first level an overview of the machine park, showing the total number of monitored machines, or any other aggregation meaningful to the administrator. A second level provides information classified by federation States. Selecting in a third level, the user can view data from a specific city and at the last level the machines are displayed individually.

The first version was developed with the Pentaho (www.pentaho.com) tool, but due to the lack of some desirable native features, like caching, resulting in a noticeable slowness in requisitions answers, it was replaced by the Play Framework (www.playframework.com) with the Highcharts (www.highcharts.com).

Experimental Results

All the tools used in the project are open source software, as well as the final product delivered (http://git.c3sl.ufpr.br). The result of the implementation can be seen in the portal http://proinfodata.c3sl.ufpr.br.

Figure 1 presents the visualization of availability information of the computer park for a region (a) and for a federation State (b). The pie chart shows global information, whilst the bar chart groups the data by region, and the line chart shows the history of the last six months. When selecting a city, a report containing the data from all machines of monitored schools within that city is generated.

Currently, the number of monitored computers with Linux Educacional is 139,045, with Windows is 246, and with other systems is 4,323, summing up to 143,614 machines. The staging/dw model was tested with approximately 200,000 connections per day, writing data individually and in parallel.

Discussion and Conclusions

The results show that the proposed model and the subsequent implementation are effective and allow the administrator to manage the set of laboratories distributed over the country, based on a system that is optimized to support the giant number of clients that should send status information to a central server.

The hierarchical approach makes easy to the user to locate the information needed. The color codes used to identify the groups of machines according to the time elapsed since the last contact make easy to recognize problems such failures and machines that were not yet put into operation. According to the Data Mart model, the information of individual machines is consolidated calculating a priori, once a day, subtotals for cities, States and regions, accelerating the responsiveness of the system to user queries. One fundamental characteristic is that the system is open source, allowing code inspection and assurance of privacy about personal data. As future work, it could be added artificial intelligence modules able to find anomalous behaviours and to generate alarms to the administrator. Also, since the system is modular and designed to be platform independent there are few obstacles to continuous improvements.

Fig. 1 .

 1 Fig. 1. Data about availability grouped by Region (a) and State (b)


Dairelys García Rivas
email: dgrivas@uci.cu@www

Book Locator: books manager

After performing a study of digital books organizing tools, it's observed that these don't count on a multi platform integration, and those who do, don't count on the elements pursued in the investigation. It is decided then to proceed to the implementation of a book organizer software, taking an initial requirements list from the studied tools, following the guidelines of the collaborative and open source development. It has been developed to its version 4.1, which after going through different development processes, detecting mistakes and adding new functionalities that join to the requirements list, it's fully functional.

Introduction

With the increasing use of information technologies and Internet, it becomes increasingly common to use digital documents to save the information. Books are not an exception; since the growth of these technologies, people have tended to favor digital reading. This is also linked to the development of mobile devices, which allows transporting digital books. Because of this, today is much more convenient to use an Ebook Reader 1 , since they can carry thousands of books simultaneously in a confined space; plus the cost of digital books is much lower than physical books.

For this situation, there have been programs that allow reading these documents, in different platforms and to various formats, being most common the PDF format. These programs, however, have characteristics that prevent people working with them on multiple operating systems. Taking into account the characteristics of these applications, summarized in Table 1: Comparison of locating books programs, will be possible to decide the most appropriate program for working on multiple platforms.

Known Results

The intended result is based on a layered architecture, in this case two layers. It uses a presentation layer to handle all the elements involved in the generation of system views (Add, Delete, Advanced) and the warning and error messages. The other layer used focuses on controlling access to data, validating the data before inserting it into the database and also performs queries to it, returning the results to the presentation layer .

In the main menu, there are available the options "Add book", "Delete book", "Edit book", "Advanced Search" and "Exit". The latter option terminates the application execution. In the "DB" menu are the database management options (" Create new BD", "Insert / Remove Language", "Insert / Remove Format" , "Insert / Remove genre") and in the "Utilities" menu are other utilities that the user might need ("Amount of read books", "To read books list", "Genre / Format / Language most read" and "Credits").

The interface also has a tab panel, where you can find all the books inserted, sorted in alphabetical order or by the author who wrote it. When double-clicked on the author's name, the names of the books he has written will be displayed. At the top of the window you there is a search by book name or by the name of the author who wrote it; in each case the results are shown in the panel tab. On the right side you can see the book information once you have selected in the left tab. In the bottom of the window there is a text element to be updated with interesting facts the author, as the total number of books out there, or how many books he has written an author if you select it on your tab.

The program has been tested by a group of developers of the Operating Systems Department in Cesol Center, Faculty 1. They have positive opinions regarding its functionality and support multiple platforms. The views on this have varied depending on the personal tastes of the users and the features that they want to have in a program. These recommendations have been reported to be taken into account for future releases, and it has been proposed to be inserted in the repository of the Cuban GNU / Linux distribution, Nova.

Table 1 .

 1 Comparing books locating programs

	Name	Language Platform Special features	Supported
				formats
	mCatalog English	Windows -	All

1

A term that refers both to an electronic device used to read books in digital format.


Amiangshu Bosu
email: asbosu@ua.edu

Jeffrey C Carver
email: carver@cs.ua.edu

Munawar Hafiz
email: munawar@auburn.edu

Patrick Hilley
email: philley@friars.providence.edu

Derek Janni
email: derekjanni@lclark.edu

When are OSS developers more likely to introduce vulnerable code changes? A case study

Keywords: Open Source, OSS, FOSS, security, vulnerability

We analyzed peer code review data of the Android Open Source Project (AOSP) to understand whether code changes that introduce security vulnerabilities, referred to as vulnerable code changes (VCC), occur at certain intervals. Using a systematic manual analysis process, we identified 60 VCCs. Our results suggest that AOSP developers were more likely to write VCCs prior to AOSP releases, while during the post-release period they wrote fewer VCCs.

Motivation

The presence of a security vulnerability in a widely used software, like Android, can be critical. Therefore, project management will be able to make informed decisions on allocating scarce security experts, if they can predict 'where', and 'when' vulnerable code changes (VCC) are more likely to be introduced. Most of the prior studies [START_REF] Meneely | Secure open source collaboration: an empirical study of linus' law[END_REF][START_REF] Neuhaus | Predicting vulnerable software components[END_REF] on vulnerability prediction considered the 'where' aspects. To investigate the 'when' aspects, this study analyzes 60 VCCs from the Android Open Source Project (AOSP) to determine when AOSP developers are more likely to introduce VCCs.

Study Design

The AOSP project uses the Gerrit code review system for changes submitted to the main project branch. Qe mined 18,110 changes from Aug. 09 -May 13. Using an empirically built and validated set of keywords, we identified 741 potential VCCs. Using a two step manual analysis process, we determined that 60 changes were VCCs. Figure 1 overviews our approach.

We hypothesized that: "developers introduce more vulnerabilities early in a project when it is less mature and developers are less focused on security".

Results and Conclusion

The red line in Figure 2 shows that for AOSP, project age does not seem to be the cause of VCCs. Similarly, the gray line in Figure 2 shows that the ratio of VCCs/total changes also does not seem to describe a pattern for introduction of VCCs. As neither of these factors explained the pattern, we conducted exploratory analysis on another factor, release cycle (vertical green lines in Figure 2). It seems that the release cycle may be able to partially explain the introduction of VCCs. The number of VCCs was generally increasing prior to a release and decreasing after a release (although the pattern does not hold in all cases). These results suggest that further study of VCC introduction patterns is needed across more projects. There appear to be factors other than age and total number of changes that may predict when VCCs are introduced. As further research identifies these factors, we can provide more concrete advice to project managers regarding when to emphasize security testing.

Fig. 1 .

 1 Fig. 1. Research Method

Fig. 2 .

 2 Fig. 2. Number of VCCs identified during code review over 45 months

Acknowledgment

This research is supported by NC State Science of Security lablet.


divine intellect. I understood that, when he didn't have an answer, William proposed many to himself, very different one from another. I remained puzzled. "But then …" I venture to remark, "you are still far from the solution."…"I am very close to one," William said, "but I don't know which." …" Therefore you do not have a single answer to your questions?" …"Adso, if I did then I would teach theology in Paris." …"In Paris do they always have the true answer?" …"Never, " William said, "but they are very sure of their errors." …"And you," I said with childish impertinence, "never commit errors?" … "Often," he answered. "But instead of conceiving only one, I imagine many, so I become slave of none." I had the impression that William was not at all interested in the truth, which is nothing but the adjustment between the thing and the intellect. On the contrary, he amused himself by imagining how many possibilities were possible. and then he continued by stating that:

Notwithstanding the fact that, undoubtedly, Gerard be a Professor from Paris, and even if he always showed the characteristic proud attitude of every French scientist in debates, seminars, lectures and discussions, I can witness that he was never sure of his errors. He is indeed one of the most open minded "savant" whom I had the possibility to meet. I could experience personally how he has been always open to new ideas, and ready to sincerely help the younger scientists toward their personal path to original scientific research. For this reason it is a great pleasure to dedicate to him this section of the EUROMECH Colloquium 563.

We proposed Prof. Kienzler to promote the present special issue, because we believe that the creative, innovative and indefatigable scientific work of Prof. Maugin deserves to be indicated as an example for younger generations.

A short scientific biographical note

Gérard A. MAUGIN was born in the west of France in December 1944.

He is an internationally recognized specialist in continuum mechanics and wave propagation: His scientific interests span nonlinear effect in mechanics, physics and biology, in particular, solitons, fracture, coupled electro-magneto-mechanical effects, media with microstructure and smart materials. He describes himself as a French mechanical-aeronautical engineer with an American education and a strong interest in mathematical physics.

He was basically educated in Paris (Mechanical Engineer, 1966;Aeronautical Engineer, 1968;MSc in Mathematics, 1968) and Princeton, USA (MA, 1969, PhD, 1971), and was granted his Doctorat d'État ès Sciences Mathématiques in Paris-6 in 1975. Director of Research at the Centre National de la Recherche Scientifique (Physical Sciences for Engineering), having been a motive power in the group on Continuum Mechanics at University of Paris-6 in the environment of Paul Germain, he became Head of the "Laboratoire de Modélisation en Mécanique", a large research unit devoted to all aspects of theoretical fluid or solid mechanics, at the Université Pierre et Marie Curie (UPMC) in Paris. Then, he created (2006) the "Institut Jean Le Rond d'Alembert" that gathered both theoretical and experimental studies in mechanics, acoustics and energetics, including such original fields as musical acoustics, in the renovated buildings of the UPMC. He also taught graduate courses (electromagnetic media, nonlinear waves, plasticity, fracture, configurational forces) in the same institution. He is emeritus in service since October 2010.

He has lectured on all continents, published about 350 refereed papers in journals of mathematical physics, theoretical mechanics and applied mathematics, contributed to some 200 proceedings of international conferences, and is the author or co-author of twelve monographs or textbooks including:

1. the pioneering Continuum Mechanics of Electromagnetic Solids (Elsevier, 1988, in Russian, Mir, 1991), the encyclopedic Electrodynamics of Continua (two volumes, Springer, New York, 1990, co-authored with A. C. Eringen; soft-cover reprint 2012), 2. the specialized monograph on Nonlinear Electro-Mechanical Couplings, (J. Wiley, 1992; co-authors J.

Pouget, R. Drouot and B. Collet) the much focused textbook entitled Thermomechanics of Plasticity and Fracture (Cambridge, 1992;in Japanese, 2000), 3. the original Material Inhomogeneities in Elasticity (Chapman and Hall, 1993)-first book of its kind, and also 4. Nonlinear Waves in Elastic Crystals (Oxford Mathematical Monographs, 1999), 5. The Thermomechanics of Nonliear Irreversible Behaviors (World Scientific, 1999), and recently 6. Numerical Simulation of Waves and Fronts in Inhomogeneous Solids (World Scientific, 2008, co- Starting in 1989, together with Marcelo Epstein (Canada) and Carmine Trimarco (Italy), he was one of the most creative and never tired contributors to the theory of so-called configurational forces (driving forces on defects and inhomogeneities in a general manner) following the path opened by the pioneering works of J. D. Eshelby and the geometrical approach favored by Ekkehart Kröner. This led to revisiting some basic aspects of the theory of fracture (with Cristian Dascalu) and defects (with Markus Lazar and E. C. Aifantis). The last fruitful developments along this line were the application of the concept of "material force" to numerical schemes, the construction of a thermodynamically admissible numerical scheme of the volume element type in order to treat the propagation of phase transition fronts in solids (with A. Berezovski) and applications to the optimization of the finite element method (with R. Mueller and D. Gross). Another fruitful avenue has been fundamental contributions to the theory of material growth with applications to the mechanics of soft biological tissues (with Marcelo Epstein, Shoji Imatani, Sara Quiligotti, and then Pasquale Ciarletta, D. Ambrosi and L. Preziosi). The three essentials keywords in these works are "finite deformations," "structural rearrangements" and "nonlinearity," while the identified Ariadne's thread is the theory of invariants and conservation laws in the sense of Noether's theorems. The necessary background remains the general thermomechanics in a line that Pierre Duhem would not have disavowed.

Maugin's most recent subjects of interest are dynamic materials that are inhomogeneous both in space and time, the association of quasi-particles with wave modes in continua (with Martine Rousseau), and wave propagation in fractal materials (with Thomas Michelitsch). His long creative association with A. Cemal Eringen (Princeton) and his own conspectus views on this matter make that he kept a constant but critical interest in generalized continuum mechanics for which he is a much looked for expert. Although his scientific thinking was much influenced by the early reading of the book series on theoretical physics by L. D. Landau and E. M. Lifshitz, and obviously the seminal works of the Truesdellian School of continuum mechanics, with time he developed a wise good balance between formalism and pragmatism.

He has established longtime fruitful and friendly cooperations with scientists from the world over, e.g., Russia (Moscow, St Petersburg, Nizhny-Novgorod, Krasnodar, Samara), Ukraine (Kharkov), Estonia (Tallinn), Germany (Darmstadt, Kaiserslautern, Bremen, Erlangen, Stuttgart, Berlin), Sweden (Stockholm), Greece (Thessalonica, Ioaninna), Israel (Tel-Aviv, Haïfa), Italy (Genova, Pisa, Roma, Messina), Spain (Madrid, Barcelona), the UK (Nottingham, Cambridge, Edinburgh, Glasgow), Poland (Warsaw, Poznan), Canada (Calgary, Montreal, Victoria), Serbia (Belgrade, Kragujevac), Turkey (Istanbul, Ankara), Egypt (Cairo), Japan (Osaka, Kyoto), North Africa (Morocco and Tunisia), Cuba and the USA (Princeton, Berkeley, Washington-DC, Lincoln-Nebraska, Lafayette-Louisiana). He has mentored a total of 38 PhD or DSc students from many different countries and attracted to Paris post-doctoral scientists and visiting professors from all continents. He continued his scientific activities at the same pace as before in spite of heavy administrative duties in the period 1999-2009. Still he finds time to devote some more than amateurish interest to the history of science and epistemology, with a specific interest in Gabrio Piola, Pierre Duhem, Gustav von Helmholtz and the Cosserat brothers, not to forget his dear d'Alembert. He remains an aficionado of trains, real ones and models, although initially formed as an aeronautical engineer!

More about the personality of Prof. Maugin in the form of interview

We gather here the content of many conversations which we had the pleasure to have with prof. Maugin. He is a (sometimes too!) direct and opinionated man, whose knowledge spans humanities and many scientific fields. His English style maintains the clear fingerprint of a person whose mother language and education was French. He uses the English language as a modern Lingua Franca, without avoiding to use the linguistic constructions based on Latin. We enjoyed very much his brilliant wit and educated arguments.

What am I? (Qui Suis Je?): A report of some conversations with Gérard A. Maugin in June 2013

Je suis moy-mesmes la matière de mon livre (Michel de Montaigne, Les Essais, Envoy to the reader)

The question "Who are you?" considered as pertaining to an individual's identity, as asked by the police on in a court of justice, admits of a simple answer: "I am Gérard A. Maugin, born on December 02, 1944, Angers, Val-de-Loire, West of France; profession: scientist."

The following question that relates to the definition of an object of study: "What are you (the above mentioned individual) from the standpoint of a professional scientist?" requires more pondering for receiving a truly meaningful answer. Quite often during international symposia some people who meet me for the first time but who have heard of me, studied some of my papers, or read some of my books, ask me what is my formation, what are my main interests, and in short, what (not who), in reality, am I? They ask me those questions because some are a bit surprised by the thematic variety and the various styles of my published papers over a long span of time. First, it must be realized that, in the course of time (about 45 years), these papers were written with, in all, about fifty doctoral students, post-doctoral researchers, eminent visitors and active co-workers. This greatly reduces the very personal output although I always had a definite contribution in all papers published with co-workers. But it is true that this variety is puzzling.

From mechanical engineer to mathematical physicist, or the reverse, or a mix? Therefore, I come myself to the point of asking me the same questions. The answers deal with the way in which one defines oneself's occupations in science. There are several possibilities.

(a) Basing on the initial formation

A first classification is possibly based on the initial formation of the person. But this can be misleading because of the evolution of the person in time, an evolution that can put some large distance between the original diploma and the actual occupation. This we can illustrate with the case of Henri Poincaré. Who would define him now as a mining engineer, even though this may have been his formal title after his formation at the École Polytechnique and a specialization (obviously not dictated by personal taste) at the Paris School of Mines? To give other examples related to engineering, we recall that both Joseph and Johann Strauss of musical fame were educated as "civil engineers" at the Imperial-Royal Polytechnic Institute (for short in German KKPI) in Vienna, while the two American novelists of Nobel-prize caliber, Norman Mailer and Thomas Pynchon, were-like the present author-both educated as aeronautical engineers. This last coincidence may have nurtured my inclination to literary expression.

(b) Basing on the professional affiliation

Another possibility is to categorize one person by his actual professional affiliation to a special type of university department. This may also be misleading. To support this judgment, we can consider the case of scientists who, in Italy, for some historical reasons are officially members of Departments of Civil Engineering ("Scienza delle Costruzioni"), but who, in research practice, are but applied mathematicians. There are historical explanations for this situation if we remember that many mathematical methods developed in the nineteenth century, and later on justified by purer mathematics, find their origin in the solution of problems posed in mechanical and civil engineering. A rather similar situation took place in France for quite a long time when teaching rational mechanics was often delivered by true analysts while waiting for a real chair in mathematics. This may not be so strange if we remember Gustave Flaubert's definition of mechanics in the Dictionary of "Idées reçues" (generally accepted ideas) as the "lowest branch of mathematics," an idea that was still expressed with some condescendence a short time ago by Jean Dieudonné, the French mathematician most influential in the Bourbaki group. One may also wonder how to classify Archimedes and Leonardo da Vinci? We may think of them as "military engineers" (as opposed to civil engineers) since they both conceive of war machines for their mentors. But we must emphasize that Archimedes was rather an applied physicist (see his famous "principle") and Leonardo a supreme artist (his painting), and both were acute observers of nature.

In a much thoughtful short biographical sketch, I have given of myself a description as "a French mechanical-aeronautical engineer with an American education and a marked interest in mathematical physics" to which I can add "and also in the history of science and the evolution of ideas." This practically contains all good ingredients for a satisfactory definition: the initial formation, what mostly influenced the scientific practice, and the immediate side interests. Of course I am no professional historian of science. Neither am I a true philosopher, since true philosophers create new (philosophical) concepts (Note for my apology that there are very few "true" philosophers.). This is not my case. But perhaps that I am a "philosopher of nature" (i.e., a physicist) in the eighteen's century meaning. For sure I am some kind of mathematical physicist in the same way as I may require to be called a "mechanician" and an "acoustician" (see below).

(c) According to membership in professional societies

Still there are other possibilities, for instance, to what scientific societies does a scientist belong? This, in principle, should correspond to his tastes, practice and the media in which he feels most at ease and in resonance with. In my case. I have been a longtime member of • the American Mathematical Society (AMS);

• the Society of Industrial and Applied Mathematics (SIAM, USA); • the Gesellschaft für angewandte Mathematik und Mechanik (GAMM, Germany); • the American Society of Mechanical Engineers (ASME, USA); • the American Physical Society (USA);

• the Acoustical Society of America (ASA, USA); • the Society of Engineering Sciences (International but mostly American).

I am not a true (pure) mathematician although I was well trained in mathematics (applied functional analysis, differential geometry). Accordingly, the second society is more appropriate since I was already invited to deliver general lectures at some meetings organized by that society. This is also the case of GAMM which has the property to unite applied mathematics and mechanics, which seems to be in perfect agreement with most of my scientific activity. Note in passing that G.A.M.M (!) is also the full set of my initials. I participated in meetings of the ASME but seldom published in its journals. My belonging to the Physical Society seems to be justified in view of my numerous contributions in its journals, "Physical Review" and the "Journal of Mathematical Physics," and the many referee reports written for its journals. I have published about twenty papers in the journal of the ASA. As to the SES, I published about forty-five papers in its journal and was honored by a special symposium of the society in Ann Arbor when I reached 60 years of age.

(d) According to the favorite place of publication

In view of these, the place of publication of research papers may be the best indicator of the "definition" of a scientist, independently of the official name of the institute to which he is affiliated. This is how I defined a group of American scientists as "mechanical engineers" in my historical perusal of the development of continuum mechanics through the twentieth century,1 because they identified themselves with the spirit of the A.S.M.E and often published in its journals. In my case, in the interval of 1970-1990, half (i.e., forty out of eighty) of my papers were published in journals of physics or mathematical physics (essentially in the USA and the UK) and the other half in journals of engineering sciences and applied mathematics. But a clear inclination toward the second avenue was already showing that would yield the final result enunciated in paragraph (e).

(e) An external objective categorization

Finally, I recently found a nice way to label the published works of a scientist (in particular in my case, over a sufficiently long period). This is the categorization made (I do not known through what procedure) among large classes of papers in the Web of Science. Concerning my case, among 338 items recorded by this institution, the distribution was as follows on October 18, 2012:

• Mechanics (154 items),

• Engineering multidisciplinary (52 items),

• Physics multidisciplinary (48 items),

• Acoustics (40 items),

• Materials science multidisciplinary (32 items),

• Others (12 items). We see that "Mechanics" and "Engineering multidisciplinary" (what essentially means "theoretical continuum mechanics" and couplings between continuum mechanics and applied physics) represent about 60 % of the whole, while "physics" (what predominantly means "mathematical physics") stands for 14 % (theoretical), acoustics for less than 12 % and "Materials sciences" for less than 10 %. All these figures are to be considered with some caution. The reason for this is that many problems considered in all categories are connected with dynamics and the propagation of linear or nonlinear waves, so that (physical) "Acoustics" is very much underestimated. Also, many of the papers in four of the categories indeed relate to the "thermomechanics" of continua. Finally, the spirit of mathematical physics permeates all papers through variational formulations, application of group-theoretical methods, space-time formalism, etc. But the "multidisciplinary" attached to several of the above given categories is also a mark of a certain type of works, most of them partaking of continuum mechanics, applied mathematics, and a strong physical background. I find this adequate enough. Note that this is not being a polymath because all works are in fact related to the same large field, phenomenological physics, although a constant interest in the comparison between discrete and continuous descriptions is present (e.g., in soliton theory, consideration of quasi-particles, lattice dynamics).

And who is he to us? A man of an extremely vast scientific, historical and artistic curiosity. Being avid of knowledge he has been also privileged by an excellent memory, a good sense of analysis and a real critical capacity. Not much interested by sportive activities, long walks in the countryside or refined meals, he much prefers discussing various subjects along with a simple dish, especially if he appreciates the company around him. He is always fond of a short and amusing story with a touch of humor! However, he is a man of forceful personality that can take a sharp position on some points especially if they bother him. A sincere man, faithful to friendship, who will willingly listen to the people in his surrounding who know they can always rely on his discretion, his friendly advises and his generosity. We conclude with the citation from "Les caractères" by Jean de la Bruyère depicts quite well-in our opinion-Gérard Maugin 's ways of managing his career as a scientist. "La liberté n'est pas oisiveté; c'est un usage libre du temps, c'est le choix du travail et de l'exercice. Etre libre, en un mot, n'est pas ne rien faire, c'est être seul arbitre de ce qu'on fait ou de ce qu'on ne fait point. Quel bien en ce sens que la liberté!"

Personal Acknowledgments

The three guest editors of the special issue honoring Prof. Maugin on occasion of his 70th birthday would like to thank first of all Gérard Maugin himself. In different moments of their academic life, they could exploit his scientific and personal support, who motivated them to continue and better their efforts in scientific research. The generosity of Prof. Maugin is witnessed by the huge amount of scientists who admit to have been his pupils.

Obviously a special thanks must be reserved to Prof. Kienzler, who made this issue possible and whose invaluable advice was very precious in many circumstances. Finally, the efforts of all authors must be recognized: The peer-reviewing process was kept at the highest standards also in this occasion, and all authors were very careful and attentive to meet them.

He was honored by several medals and prizes including: a

  CNRS Medal in 1977, a Prize of Mechanics from the French Academy of Sciences in 1982, the Max Planck Research Award for 2001 conferred by the German Federal Republic, and the SES Eringen Medal from the Society of Engineering Science, USA(2003). He has received honorary doctoral degrees from different countries, e.g., from the Lomonosov State University in Moscow, the Technical University of Darmstadt and the Aristotle University in Thessaloniki. He is a foreign member of the Polish Academy of Sciences, of the Estonian Academy of Sciences and a member of several Together with Estonian, Russian, Bulgarian and Ukrainian colleagues he participated in the construction of new classes of solutions in realistic physical models of deformable crystals. He also contributed to the theory of linear and nonlinear bulk waves and surface waves on solid substrates (with S. Cadet, J. Pouget, A. Miled, H. Hadouaj, A. N. Abd-Alla, A. F. Ghaleb, A. V. Porubov, C. I. Christov, A. Salupere, B. A. Malomed) and to the theory of wave propagation through multilayered and inhomogeneous structures (with V. Alshits). Following the

	authored
	with A. Berezovski and J. Engelbrecht from Estonia),
	7. the lengthy Configurational forces (CRC/Taylor and Francis, 2011), and a historical perspective in
	8. Continuum Mechanics Through the Twentieth Century (Springer, 2013) and the Eighteenth and Nineteenth
	Centuries (Springer, 2014).
	He has edited eleven volumes of proceedings of international conferences, e.g., the two-volume set Continuum
	Models and Discrete Systems (Longman, 1990), or volumes dealing with deformable electromagnetic bodies,
	waves or the mechanics of Cosserat continua (Springer 2010, 2011), and also special issues of journals such as
	Wave Motion, Mechanics Research Communications, and the International Journal of Engineering Sciences.
	He has been much active in the edition of these journals as well as in that of the International Journal of
	Electromagnetics and Mechanics (co-founded in 1991), the Journal Applied Archives of Mechanics and the
	Journal of Thermal Stresses. He generously contributed his expertise to the appraisal of scientific research
	programs in about ten countries. He never neglected more menial duties such as the review of published papers
	and the critical assessment of new books in theoretical mechanics or applied mathematics. He dutifully sat for
	9 years on the national selection committee for admission and promotion of professional researchers at CNRS.

professional societies (ASME, AMS, APS, ASA, SIAM, GAMM, ISIMM, …). An international colloquium was held in his honor in Ann Arbor, Michigan, in 2003, and a Festschrift volume was published on that occasion with contributions from all over the world. He has been very much involved in cooperative programs at the European and international levels. He was selected as a member of the Wissenschaftskolleg zu Berlin in 1991-1992, as an invited visiting professor on the chair of innovative science at Kyoto University, Japan, in 1997-1998, and a Springer visiting professor at the University of California,

Berkeley, for 2004-2005. Between 1977 and 2011

, he taught in eight different courses at Udine's International Center of Mechanical Sciences (CISM) in Italy where he had participated in one of founding sessions as a student from North America in 1970.

Concerning his scientific achievements, G. A. Maugin was a pioneer in the development of the now fashionable multiphysics with a rational nonlinear electrodynamics of deformable continua and relativistic continuum thermomechanics (in Paris, under the influence of André Lichnerowicz, and at Princeton, under that of John A. Wheeler). Most of the former work now finds applications in electrical engineering and signal processing but also in the new technology of adaptive structures and so-called smart materials, while the latter works are still considered in astrophysics and the like. Some of these works were developed in cooperation with Bernard Collet, Joël Pouget, Anaclet Fomèthe, Naoum Daher, Shinya Motogi, A. Hakmi and J. Sioké-Rainaldy, with a special interest in coupled electro-magneto-elastic waves in various types of crystals and an emphasis on resonance effects (e.g., with his three Egyptian PhD students). As early as 1968, under the influence of Paul Germain, Gerald B. Whitham, Wallace D. Hayes and Martin D. Kruskal, he became interested in nonlinear waves and back in Paris created a group dealing with the propagation of nonlinear waves of different types (shocks, solitary waves, solitons) in solids in both discrete and continuous frameworks. French school of mechanics and also Joseph Kestin (Brown), he forcefully contributed to the formalization and some powerful illustrations of the thermomechanics of bodies with internal variables of state (with Wolfgang Muschik), including for solutions of macromolecules (with Raymonde Drouot and Angelo Morro) and hysteresis in ferromagnetics and ferroelectrics (with M. Sabir, A. F. Ghaleb and his co-workers), and some other modeling problems with J. Engelbrecht and A. Berezovski. He got involved in the homogenization of elastic and electro-elastic composites within cooperations with Nicole Turbé in Paris and Reinaldo Rodriguez-Ramos from Cuba.

G. A. Maugin (2013), see the Appendix in Continuum mechanics through the twentieth century-a concise historical perspective, Springer, Dordrecht-New York.