Eeva Järvenpää
email: eeva.jarvenpaa@tut.fi

Minna Lanz
email: minna.lanz@tut.fi

Guidelines for Designing Human-Friendly User Interfaces for Factory Floor Manufacturing Operators

Keywords: User-centric design, human-friendly design, user interfaces, manufacturing environment, manufacturing IT-systems

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Introduction

Human factors play a crucial role in manufacturing. The desire towards more agile and responsive manufacturing requires that real time information of the production plan, status and other relevant aspects is always visible for those who need it, when they need it. This, in turn, requires that the information is, on one hand collected from the production processes, and on the other hand displayed to the workers in a humanfriendly way. Still common manual practices in information inputting, e.g. re-typing information from paper documents to IT-systems, don't allow real time transparency to the operations, neither provide reliable and timely information of the realized production.

The interviews conducted among 25 Finnish manufacturing companies [START_REF] Järvenpää | Production planning and control in Finnish manufacturing companies -Current state and challenges[END_REF] showed that even though the companies have not yet widely adopted proper manufacturing IT-solutions, such as Manufacturing Execution Systems (MES), there is a strong desire to increase the digitalization in manufacturing. MES would support real time data collection from the manufacturing operations in a digital format, and this data could be used throughout the organization for better and more synchronized management and control of the operations [START_REF]Manufacturing Execution Systems -MES[END_REF]. In order to mitigate problems relating to human perceptual and cognitive capabilities, as well as behaviour, a special attention should be paid on the design and selection of good and intuitive user interfaces (UIs) for the new manufacturing IT-systems. The novel ways of working on the factory floor should not only improve the efficiency and quality of operations, but also be pleasurable for the workers. To attract future operators, the manufacturing sector should target to social sustainability and adopt new UI technologies in order to be more appealing and accessible for youngsters who have grown into a digital world [START_REF] Berlin | Social Sustainability Challenges for European Manufacturing Industry: Attract, Recruit and Sustain[END_REF].

This paper discusses a study conducted in an ongoing LeanMES-project. The project's objective is to create a lean, scalable and extendable concept for a new type of MES that supports human operator in a dynamically changing environment. One target is to study novel approaches for intuitive user interfaces. The purpose of this paper is to draw the background for the development of UIs for factory floor operators by highlighting some relevant theory for user-centric design, and identifying and analysing the current challenges and needs of manufacturing companies. The focus of this paper is on information display and collection.

2

Research method

The characteristics of a good design depends on the users, tasks and context of use of the designed technology (e.g. [4][6]). Therefore the research approach taken for this study was to analyse all these three aspects, namely users, tasks and context. The research, discussed in this paper, consists of the following steps:

1. Interviews: The data for the analysis was collected form the interviews conducted among 25 Finnish manufacturing companies mainly from machine building industry. In each company three types of personnel were interviewed to get a comprehensive view on the needs, current challenges and underlying context: 1) plant or production manager; 2) production worker and 3) main user of the production planning and execution system or IT manager. The questions focused on the everyday production planning and control, change situations, data collection and search, quality control practices and work instructions. For more information on the interviews, please refer to [START_REF] Järvenpää | Production planning and control in Finnish manufacturing companies -Current state and challenges[END_REF]. 2. Literature review: Literature review on user-centric design, human-computer interaction, and existing and emerging UI technologies was conducted. The purpose was be able to take into account the relevant characteristics when making selections for proper input and output modalities, medias, technologies and display designs. 3. Task analysis: As LeanMES-project focuses on the information flows and visibility, the main focus in the task analysis was to map the required information inputs and outputs on different workstations and tasks. The purpose was not to perform this analysis for any individual company, but to generalize the results for machine building industry.

Analysis of suitable input and output modalities, media and UI technologies:

While designing user interfaces, three selections need to be made: 1) Selection of the modality, which refers to the sensory channel that human uses to send and receive a message (e.g. auditory, visual, touch); 2) Selection of the medium, which refers to how the message is conveyed to the human (e.g. diagram, video, alarm sound); and 3) Selection of the technology to deliver the message (e.g. smart phone or workshop PC). These were analysed on the basis of the task requirements.

3

User-centric, human-friendly user interface design

Human characteristics relevant for usable design

Based on [START_REF] Ritter | Foundations for designing user-centered systems -What System Designers need to know about people[END_REF], whether a system can be described being usable or not depends on four factors, namely anthropometrics, behaviour, cognition and social factors. Attention refers to the selective aspects of perception, which function so that at any instant a user dedicates his limited information processing capacity to the purposeful manipulation of a subset of available information [START_REF] Welsh | Perceptual-Motor Interaction -Some Implications for Human-Computer Interaction[END_REF]. According to [START_REF] Proctor | Human Information Processing -An Overview for Human-Computer Interaction[END_REF] many studies have shown that it is easier to perform two tasks together when they use different stimulus or response modalities, than when they use the same modalities. According to multiple resource models, different attentional resources exist for different sensorymotor modalities and coding domains [START_REF] Proctor | Human Information Processing -An Overview for Human-Computer Interaction[END_REF].

Mental models are used to understand systems and to interact with systems. Based on Ritter et al. [START_REF] Ritter | Foundations for designing user-centered systems -What System Designers need to know about people[END_REF] mental model can be considered as a representation of some part of the world that can include the structures of the world, how they interact and how the user can interact with them. Payne [START_REF] Payne | Mental Models in Human-Computer Interaction[END_REF] simplified the meaning of mental models into "what users know and believe about the systems they use". The model the user brings to the task will influence how they use the system, what strategies they will most likely employ, and what errors they are likely to make. It is therefore important to design the system in such a way that the user can develop an accurate mental model of it. [START_REF] Ritter | Foundations for designing user-centered systems -What System Designers need to know about people[END_REF] One important concept, which aids in building the correct mental model of the system, and therefore easing its usage, is the stimulus-response (S-R) compatibility. This means that there should be clear and appropriate mappings between the task/action and the response. It is typically seen as having physical aspects of an interface (e.g. buttons) and displays match the world that they are representing. [START_REF] Welsh | Perceptual-Motor Interaction -Some Implications for Human-Computer Interaction[END_REF]

Guidelines for designing interfaces with good usability

Several authors have given guidelines and heuristic principles for designing user interfaces with good usability. In the following are collected the most relevant guidelines specifically for LeanMES-project's purposes.

 Usage of terms and language: The system should speak the user's language and use words they already know and which are relevant for their context. The UI should exhibit consistency and standards so that the same terms always mean the same thing. Consistent use of words strengthens the chances of later successfully retrieving these words from the memory. [START_REF] Ritter | Foundations for designing user-centered systems -What System Designers need to know about people[END_REF], [START_REF] Nielsen | 10 Usability Heuristics for User Interface Design[END_REF]  Use recognition rather than recall: Systems that allow users to recognize actions they want to do will be easier initially to use than those that require users to recall a command. [START_REF] Ritter | Foundations for designing user-centered systems -What System Designers need to know about people[END_REF], [START_REF] Nielsen | 10 Usability Heuristics for User Interface Design[END_REF]  Favour words over icons: Instead of displaying icons, words may be better. This is because retrieving names from memory is faster than naming objects.

[10]  Information reliability and quality: The user should not be provided with false, misleading, or incomplete information at any time [START_REF] Hedge | 10 principles to avoid XP-asperation[END_REF].

 Show only information which is needed: The system should be aesthetic and follow minimalist design, i.e. do not clutter up the UI with irrelevant information [START_REF] Nielsen | 10 Usability Heuristics for User Interface Design[END_REF].  Provide feedback for the user: The current system status should always be readily visible to the user [START_REF] Ritter | Foundations for designing user-centered systems -What System Designers need to know about people[END_REF], [START_REF] Nielsen | 10 Usability Heuristics for User Interface Design[END_REF], [START_REF] Hedge | 10 principles to avoid XP-asperation[END_REF].  Make available actions visible: Make the actions the user can (and should) perform easier to see and to do [START_REF] Ritter | Foundations for designing user-centered systems -What System Designers need to know about people[END_REF].

 Allow flexibility for different users: The system should have flexibility and efficiency of use across a range of users, e.g. through keyboard short-cuts for advanced users. [START_REF] Nielsen | 10 Usability Heuristics for User Interface Design[END_REF]  Ensure that critical system conditions are recoverable: The user should have the control and freedom to undo and redo functions that they mistakenly perform [START_REF] Nielsen | 10 Usability Heuristics for User Interface Design[END_REF], [START_REF] Hedge | 10 principles to avoid XP-asperation[END_REF].

In their book Wickens et al. [START_REF] Wickens | An Introduction to Human Factors Engineering[END_REF] defined 13 principles for display design, which should be taken into account when designing the LeanMES UIs:

 Perceptual principles: 1) Make displays legible (or audible); 2) Avoid absolute judgement limits; 3) Remember that user's past experience affects to how the signals are likely to be perceived and interpreted; 4) Build redundancy to the system, i.e. present the same signal in multiple different forms or modalities; 5) Use discriminable elements.

 Mental model principles: 6) Utilize pictorial realism, i.e. make a display to look like the variable that it represents; 7) Put the moving elements to move in a pattern and direction compatible with the user's mental model.  Principles based on attention: 8) Minimize information access cost by allowing for frequently accessed sources to be located at the nearest possible position; 9) If divided attention between two information sources is necessary for the completion of one task, make them to have close mental proximity; 10) Utilize different cognitive resources (e.g. vision and hearing) if multiple information must be presented simultaneously.  Memory principles: 11) Replace memory with visual information; 12) Provide information predictively; 13) Utilize consistency among different displays.

Several things have to be considered when designing visual communications, such as web pages, different visual displays or dashboards. These include aspects such as typography (including typeface, its style, size, word spacing, leading, line length), colour, field of vision, page layout design, and amount of information on display. When using colour to show e.g. qualitative differences or highlight key data, it should be remembered that at least 9% of population is colour-deficient. Thus, colour should not be used as an only cue. [START_REF] Watzman | Visual Design Principles for Usable Interfaces -Everything is Designed: Why We Should Think before Doing[END_REF] Often the display size is limited, especially with hand-held devices. When evaluating how much information should be presented on the display screen, the demands from cognitive and visual perspectives may be contradicting. According to [START_REF] Schlick | Visual Displays[END_REF], presenting little information on a screen at time helps to avoid visibility problems resulting from high-information density. On the other hand, presenting as much information on screen as possible allows users to have maximum foresight (cognitive preview) of other functions on the menu, which should benefit information access from a cognitive point of view and minimize disorientation. [START_REF] Schlick | Visual Displays[END_REF] 4 Results

Identified challenges relating to information inputting and display

The performed interviews revealed multiple challenges relating to the current information inputting and display practices on the factory floors. The main challenges, encountered especially in small and medium sized companies, are summarized below:

1. The paper work orders and documents, still commonly used to control the production and to collect information from the factory floor (e.g. time stamps, quality data, measurements), were regarded as problematic, because they don't provide real time information of the operations and their status. In addition, the information written on paper must be re-typed to IT-systems, which is non-value adding manual work, prone to human errors. 2. Paper documents are cumbersome to update and they get easily lost, e.g. work instructions are not up-to-date and rescheduling or re-routing of the orders requires the production supervisor to go physically to each workstation to change the order of the jobs. 3. The current information inputting practices don't produce reliable, timely data of realized production. Many companies stated that the operators tend to forget to record the receipts or they do it only once a day. The existing UIs are cumbersome to use, or are not in the same physical location with the operator (e.g. shared computers). This has often led to such practice that the recordings are done in batches rather than immediately after the event that should be recorded. 4. The recordings or information search require often long sequence of numbers, e.g. serial, order or project number, to be manually typed to the system. This is time consuming and error prone activity. 5. The usability of the current IT-systems used in manufacturing is often poor. The operators may use substantial time of their day to searching for information.

Task analysis

As LeanMES-project focuses on the information flows and visibility, not in humanmachine collaboration in general, the main focus in the task analysis was to map the required information inputs and outputs of different roles in the factory. The roles were defined based on the tasks which are performed on different workstations. The following tasks/workstations were analysed: machining (milling and turning), sheet metal cutting, welding, assembly, as well as material receiving and shipping. The generic information needs and outputs on different tasks/workstations were systematically identified based on the interviews and workshops with industrial partners, and drawn as information input-output graphs (Figure 1). These graphs didn't take a stand on if human involvement is needed or if machine can manipulate or produce the information automatically. The purpose was to allow different automation strategies and the allocation of the functions to either human or machine for example based on the Fitt's list (MABA-MABA approach) [START_REF] Ritter | Foundations for designing user-centered systems -What System Designers need to know about people[END_REF].

Machining centre

Operator Operator

Example of selecting the modality, media and technology

The information elements in the input-output graphs were systematically categorized into physical items, spatial items, conceptual information, dynamic procedural information, events, descriptive information, values and causation, as exemplified in Figure 1. Based on this division, suitable modality and media were suggested for each information element relying on the heuristics presented by [START_REF] Sutcliffe | Multimedia User Interface Design[END_REF]. Below one example is discussed.

In case of the machining centre's loading or unloading order, the attention of the operator has to first be captured. Especially in multi-machine operating mode, when the operator is performing multiple tasks simultaneously and doesn't have direct visual sight to the machines all the time, the suitable modality for capturing the attention could be auditory or touch (haptic). This way the operator can concentrate on the current task at hand, which most probably requires visual attention, and simultaneously receive information about the upcoming task by using other attentional resources than vision. Such output could be produced e.g. by smartphone in the operator's pocket or smart watch in his/her wrist alerting, vibrating and possibly giving spoken information about the upcoming task. After capturing the operator's attention and guiding him/her to the correct machine, the task procedure has to be instructed to him/her. For such information, containing a lot of details and information elements, vision should be used as a main sensory channel. As discussed in [START_REF] Payne | Mental Models in Human-Computer Interaction[END_REF], multi-media work instructions have been proved more powerful compared to single media instructions. Therefore, the detailed task procedure may be shown as a sequence of still images, video or animation, supplemented with text-based or audio instructions. For displaying this information, larger screen is preferred next to the machine, as not so much information can be conveyed through small smart phone display without compromising the visibility. When the task is completed, the operator should record the task done through the same UI by just one click. The task status gets updated to the MES and the information is immediately visible to others.

Discussion and Conclusions

Human-friendly UI design is crucial when aiming for efficient operations. The identified challenges in Finnish manufacturing companies clearly show that there is a need for digitalization and adoption of new UIs on the factory floors. As noticed during the interviews, human involvement increases flexibility of the production system, but also causes uncertainty to the information management processes. In order to mitigate this problem, a special attention should be placed on good and intuitive UIs and human-computer interaction technologies. These UIs should bring the needed information to the operator without searching and allow effortless information inputting. This paper highlighted some important human characteristics and design considerations for user-centric UI design, especially from the manufacturing IT-systems' perspective.

The goal of the LeanMES-project is to support human operator especially from the information acquisition and inputting viewpoints. Therefore the task analysis presented in this paper concentrated on identifying the needed information elements, rather than identifying the detailed steps (or their sequence) that the worker needs to perform in order to achieve their manufacturing related goals. Example of the selection of the suitable modalities, media and UI technologies for the identified information elements was shortly presented. The future work will include testing and analysing the suggested media and technologies in real industrial contexts.

  Anthropometrics refers to the physical characteristics, such as body type and size, of the intended users. Behaviour refers to the perceptual and motivational characteristics of users, looking at what people can perceive and why they do what they do. Behavioural characteristics are mostly related to the sensation with the basic senses (sight, hearing, touch, smell and taste) and interpretation of the sensed stimuli. Cognitive factors include learning, attention and memory and other aspects of cognition that influence on how users think and what they know and what knowledge they can acquire. Social factors consider how groups of users behave, and how to support them through design.[START_REF] Ritter | Foundations for designing user-centered systems -What System Designers need to know about people[END_REF]

Fig. 1 .

 1 Fig. 1. Example of the information input-output graphs.

Acknowledgements

This research was carried out as part of the Finnish Metals and Engineering Competence Cluster (FIMECC)'s MANU program in LeanMES-project.


Miia-Johanna Kopra
email: miia-johanna.kopra@tut.fi

Nillo Halonen
email: nillo.halonen@tut.fi

Eeva Järvenpää
email: eeva.jarvenpaa@tut.fi

Minna Lanz
email: minna.lanz@tut.fi

Increasing Employee Involvement in Socially Sustainable Manufacturing: Two Methods for Capturing Employees' Tacit Knowledge to Improve Manufacturing Processes

Keywords: Employee involvement, Socially sustainable manufacturing, Tacit knowledge, Knowledge sharing, Facilitation, Experiential learning, Process development

Talented workforce is one of the main strengths in Europe to overcome the economic crisis and address the challenges ahead. The most valuable knowledge the employees have, is tacit and, therefore, hard to utilize in the companies. This paper presents two alternative facilitation methods to capture tacit knowledge related to the manufacturing process, thus allowing the employees participate in activities developing the manufacturing process and the development of positive company culture. The first method focuses on operational tacit knowledge, and the latter method extracts the production related tacit knowledge from the project members. Both of the methods use facilitation to guide the employees through the experience-based learning process and provide support for information and knowledge sharing.

Introduction

In the fast changing business environment, persistence in the same operating routines quickly becomes hazardous [START_REF] Zollo | Deliberate Learning and the Evolution Dynamic Capabilities[END_REF]. The organizations need to learn to adapt their routines, especially if the actions do not produce the intended outcome, or they produce an undesirable outcome. Organizations can learn when they have a shared vision of their aspirations and the future [START_REF] Senge | The Fifth Discipline: The art & practice of the learning organization[END_REF]. The vision requires management commitment, which is visible in the investment they made in resources and work processes, supporting learning in the organization [START_REF] Sense | Facilitating conversational learning in a project team practice[END_REF].

In a socially sustainable corporate culture, the individuals can thrive, continuously develop their talents and use them in the industry [START_REF] Fantini | Preliminary findings from the Socially Sustainable Manufacturing Ecosystems Workshop[END_REF]. When the work environment is stimulating, the employees are contributing themselves to the development of instructions and knowledge [START_REF] Berlin | Preliminary findings from the 2nd Socially Sustainable Manufacturing Ecosystems Workshop[END_REF]. Internally generated ideas enable the employees to associate more strongly with the task, and to have greater commitment to it [START_REF] Kessler | Internal vs. external learning in new product development: effects on speed, costs and competitive advantage[END_REF]. Committed employees are motivated and willing to put extra effort in their jobs [START_REF] Lin | To share or not to share: modeling knowledge sharing using exchange ideology as a moderator[END_REF]. As a result, they work more efficiently and improve their organizations' possibilities to succeed.

Also, socially sustainable organizations share knowledge between the organizational units [START_REF] Berlin | Preliminary findings from the 2nd Socially Sustainable Manufacturing Ecosystems Workshop[END_REF]. Such an organization promotes participatory behaviour and encourages the employees to take a broader view on their jobs, and to consider a wider variety of information, inputs and constraints in their decision making process [START_REF] Sarin | The Effect of Team Leader Characteristics on Learning, Knowledge Application, and Performance of Cross-Functional New Product Development Teams[END_REF]. Organization should fight the Not-Invented-Here (NIH) syndrome and emphasize that everyone can have a good idea [START_REF] Berlin | Preliminary findings from the 2nd Socially Sustainable Manufacturing Ecosystems Workshop[END_REF]. NIH refers to the bias against using knowledge from other sources, i.e. people hesitate to share what they have and to use what others have [START_REF] O'dell | If Only We Knew What We Know: Identification and Transfer of Internal Best Practices[END_REF][START_REF] Von Krogh | Enabling knowledge creation: how to unlock the mystery of tacit knowledge and release the power of innovation[END_REF]. Also, a democratic organizational climate leads to the free exchange of the ideas and to more opportunities for the cross-functional knowledge fertilization, thus preventing localized and isolated problem solving.

This paper presents two alternative facilitation methods, which allow the employees to capture tacit knowledge related to manufacturing process. The employees can participate in activities developing the manufacturing process and the development of positive company culture. Involving the employees in the process development, the company encourages socially sustainable corporate culture, where the employees can develop and use their talents. Also, the employees are invited to contribute to the development of instructions and knowledge. The first method focuses on operational tacit knowledge, and the latter method extracts the production related tacit knowledge from the project members. The methods also support experiential learning in the projects, as well as, information and knowledge sharing in the organization.

Tacit knowledge in organizations

An increasing number of the organizations use projects and team working to achieve the objectives, and to adapt to the changing business environment. Projects generate a vast amount of knowledge on the organizational processes, as well as, technical knowledge on the products [START_REF] Goffin | Managing Lessons Learned and Tacit Knowledge in New Product Development[END_REF]. Created knowledge is mostly tacit in nature and such knowledge cannot be taught, trained or educated, but it can be only learnt and the learning process takes time [START_REF] Haldin-Herrgard | Difficulties in diffusion of tacit knowledge in organizations[END_REF].

Physical face-to-face experiences are the key to conversion and transfer of tacit knowledge [START_REF] Nonaka | The Concept of "Ba": Building a Foundation for Knowledge Creation[END_REF]. [START_REF] Zollo | Deliberate Learning and the Evolution Dynamic Capabilities[END_REF] see that by sharing their individual experience and comparing their opinions with those of their colleagues, the project members can achieve an important level of understanding of the causal mechanisms intervening between the actions required to execute a certain task, and of the performance the outcome produces.

The problem of knowing who knows what, grows with the size of the organization and finding a person with relevant tacit knowledge may not be easy [START_REF] Smith | The role of tacit and explicit knowledge in the workplace[END_REF]. Small companies can list their employees' skills (e.g. related to manufacturing tools) in a spreadsheet and the production supervisor knows the staff, their skills and experiences, based on his experience [START_REF] Järvenpää | Production planning and control in Finnish manufacturing companies: Current state and challenges[END_REF]. Dependency on tacit knowledge only creates a huge risk for the organization. For example, especially small companies do not usually have proper manufacturing IT systems in use. When the manufacturing planning and con-trol activities are done based on the tacit knowledge of the production planner or supervisor, then nobody knows how to update the manufacturing plan, if the person is absent. Often the Excel spreadsheets used for production planning and scheduling, are only available and understandable for the person who created them.

Another troublesome aspect of tacit knowledge, is its elusiveness [START_REF] Stenmark | Leveraging Tacit Organization Knowledge[END_REF]. There may not be effective ways in the organization to elicit tacit knowledge from the individuals, or the organization's culture might actively discourage knowledge sharing, either deliberately or incidentally [START_REF] Falconer | Organizational learning, tacit information, and e-learning: a review[END_REF]. Also, people may not be fully aware of their tacit knowledge or they do not have any personal need to make it explicit, or there is a potential risk of losing power and competitive advantage, when making tacit knowledge explicit [START_REF] Stenmark | Leveraging Tacit Organization Knowledge[END_REF]. Especially in small manufacturing companies, systematic practices for capturing and sharing tacit knowledge are rare [START_REF] Järvenpää | Production planning and control in Finnish manufacturing companies: Current state and challenges[END_REF].

Some authors (e.g. [START_REF] Nonaka | A Dynamic Theory of Organizational Knowledge Creation[END_REF]) think that tacit knowledge needs to be made explicit for sharing, thus making codification an essential step in leveraging the value of knowledge in the organization. Knowledge codification allows knowledge to be accessed and used by some others, sometime in the future, and it is not dependent on the personal networking [START_REF] Newell | Developing a dynamic project learning and cross-project learning capability: synthesizing two perspectives[END_REF]. However, the effort to reduce tacit knowledge nearly always skews knowledge and separates it from its vital context [START_REF] Goffin | Managing Lessons Learned and Tacit Knowledge in New Product Development[END_REF].

Learning from the past

The organization cannot learn from the projects, unless the project members' knowledge is articulated and transferred to the others [START_REF] Riege | Three-dozen knowledge-sharing barriers managers must consider[END_REF]. Knowledge from project to project flows through direct and detoured transfers [START_REF] Jeon | Success Factors for a Lessons-Learned System in a Construction Organization[END_REF]. The mediums of direct transfers are mainly employees, who directly move to the next project with knowledge achieved from the previous project. Detoured transfers occur through e.g. knowledge repositories, company manuals, training programs and work processes.

Lessons learned is any form of knowledge, gained from the direct experience, successful or otherwise, to improve the performance in the future [START_REF] Jeon | Success Factors for a Lessons-Learned System in a Construction Organization[END_REF]. Everyone benefits from reviewing past activities and decisions, to learn what worked, what did not, what can be changed and what must be managed. Usually, the projects are not willing to invest much time in the learning activities, because that time is taken away from other responsibilities, which have a higher priority [START_REF] O'dell | If Only We Knew What We Know: Identification and Transfer of Internal Best Practices[END_REF]. Therefore, the learning process needs to be prompted and structured, to be meaningful and useful for the projects.

In most business organizations, failure and fault are virtually inseparable, and examining past activities in depth is emotionally unpleasant and can chip away the individual's self-esteem [START_REF] Edmondson | Strategies For Learning From Failure[END_REF]. In the end, learning from the past is reliant upon the project members' willingness to admit mistakes or deficiencies in their actions, to engage in conversation about those issues, and to subject themselves and their experience to the constructive criticism of their peers [START_REF] Sense | Facilitating conversational learning in a project team practice[END_REF].

The willingness to expose oneself is related to the perceived quality of their peer relationship. Therefore, the way the project evaluation is facilitated, is crucial [START_REF] Stenmark | Leveraging Tacit Organization Knowledge[END_REF]. Facilitation is a process in which a person, the facilitator, helps a group of people complete their work and improves the way the group works together [START_REF] Farrell | Facilitation: A formula for success[END_REF][START_REF] Herbert | Facilitator, Researcher, Politician, Magician[END_REF]. Facili-tation can reduce the cultural, professional or organizational barriers, which make communicating difficult [START_REF] Kolb | Initial contracting issues in small group facilitation[END_REF]. Facilitation also emphasizes learning from the process. This requires that the participants are offered tools to reflect on their experience [START_REF] Herbert | Facilitator, Researcher, Politician, Magician[END_REF].

Capturing operational lessons learned

A facilitation method was created for capturing the lessons learned in the project teams, to improve the project routines either in the own project (in the later phase of the project) or to propose new ways of working for some other project [START_REF] Kopra | Facilitating Experience-based Learning in Groups: A Method for Capturing Lessons Learned[END_REF]. The described facilitation method accommodates two approaches to learning: social constructive approach (e.g. [START_REF] Siljander | Systemaattinen johdatus kasvatustieteeseen[END_REF]) and experiential learning theory (e.g. [START_REF] Kolb | Experiential learning: experience as the source of learning and development[END_REF]). It also uses ideas from the model of single-loop and double-loop learning (e.g. [START_REF] Argyris | On Organizational Learning[END_REF]), the 4i framework of organizational learning [START_REF] Crossan | An Organizational Learning Framework: from Intuition to Institution[END_REF] and the theory of organizational knowledge creation (e.g. [START_REF] Nonaka | The knowledge-creating company: how Japanese companies create the dynamics of innovation[END_REF]).

The facilitation method to capture operational tacit knowledge is divided into three phases: activities prior, during and after the workshop [START_REF] Kopra | Facilitating Experience-based Learning in Groups: A Method for Capturing Lessons Learned[END_REF]. Prior the workshop, the facilitator and the project leader discuss the facilitation method, the project group, the workshop goals and the practicalities. Workshop activities are illustrated in Figure 1.

Fig. 1. Phases in lessons learned workshop

The workshop begins with a project history presentation, which defines the timeline of the activities under discussion, as well as, establishes a common ground for the conversations in the workshop. Then, the workshop participants select the topics for further analysis, to be done in the small groups, as well as, the target project for the learnings. The participants decide themselves, which topics are discussed and analysed in small groups. This allows the participants to concentrate on what they believe is important. The analysis includes a scale question related to the project performance and brainstorming ideas. The participants are assigned to small groups and they use a worksheet to document  Activities and invested resources, which contributed to the project performance concerning the selected topic.  Activities the project did not perform or resources they did not have, but which could have contributed to the project's success.

They also describe how they would have acted if they had the knowledge they currently have and all the resources available. The template guides the participants to convert their tacit knowledge into explicit, and document it. Each small group pre-sents their analysis and the others have a possibility to comment on the results. Then, the participants plan how they are going to proceed with the captured lessons learned.

After the workshop, the project implements the agreed plan, and either transfers the learnings to the identified target project, or uses the improvement ideas to modify the project's own routines. The participants review the meeting minutes and the minutes they are made available for others in the organization. The captured lessons learned and the improvement ideas are also delivered to the function or team responsible for the operational development in the organization, because the ideas can be used in improving the organizational routines.

Example A: A manufacturing project was preparing for mass-production phase. Members from the target project, i.e. a similar manufacturing project in their early phase, were invited to the workshop to ensure efficient knowledge transfer. The project was the first of a kind in the organization, and there had been many challenges and issues, which the participants wanted to discuss. The analysed topics were related to the product data management and the cooperation with the customer. The created improvement ideas formed a basis for a discussion related to the needed changes in the operational mode to support the new type of projects.

Capturing production related knowledge

In this facilitation method, the project members model and analyse the production process and share their experiences on the production using Design Reasoning Pattern (DRP) principles [START_REF] Halonen | Impacts of making design sequence explicit on NPD project in forest machinery company[END_REF]. With the help of a facilitator, the participants make the production phases and sub-deliverables explicit by modelling the existing production process into logical information flow and focusing only on value adding elements. The method is divided into six phases, which can be divided into several workshops. Phases in the method are illustrated in Figure 2.

Fig. 2. Phases in the Design Reasoning Method

First, the participants define the goals for the analysis. Then, the broader domains (i.e. functional areas of the production or organizational areas), list of subdeliverables for each domain and the design decision elements are mapped. In the third phase, the identified elements are aligned into a process description by dividing the sub-deliverables into life cycle phases and linking deliverables into a logical sequential flow. Also, the relevant checkpoints in the production are defined.

In the fourth phase of the method, the participants define time, money, human and material resource allocations into production phases, to identify the whole spectrum of production process' information, material, work and control flows and the critical path of the process. Then, the explicit production process is analysed with chosen metrics (e.g. how much of the current errors in the production are caused by lack of information of right product specifications or by inefficient information transfer within production process or what are critical production phases to be improved). Finally, the participants are able to identify the important learnings, the points of potential improvement in the production process and the solutions to make the improvements happen.

Creating the logical relations between the design elements allows the participants to develop a shared understanding regarding the production process. More importantly, by joining the different experiences of the participants together not just makes tacit knowledge explicit, but creates totally new knowledge for participants. DRP also helps the project to create a common language which, in turn, facilitates knowledge sharing in the project.

Example B: A company was trying to find the root cause for a problem in a new manufacturing line. The problem solving had already taken over 1700 man hours and the root cause for the problem was still unknown. Then, the company used 70 man hours to create a model with the DRP method and re-test the manufacturing process. The root cause for the problem was located outside the scope the quality system related parameters. The company estimated that the created DRP model was worth of one man year of labour.

Conclusions

Both facilitation methods support the idea of learning organization, which is seen as one of the important aspects of socially sustainable manufacturing. If the employees learn from their experience, then they can suggest modifications to the ways of working. Additionally, the employees are involved in defining the routines they ought to follow. Presented facilitation methods increase tacit knowledge sharing, as well as, enhance communication and openness in the organization, thus leading to better understanding of the whole, i.e. how a person's work and decisions affect to everything else. The methods also support shared leadership in projects and provide better possibilities for employee involvement, as all project members can contribute to defining common plans or ways of working. This, in turn, increases employees' motivation and commitment to the organization, and provides opportunities for the organization to succeed.

In manufacturing companies, capturing lessons learned can be used to suggest the most effortless, yet effective, ways of working or to agree common rules. Design reasoning patterns produce new system level knowledge and enhance the employees' understanding regarding the manufacturing functionalities and the dependencies be-tween them. For example, it has been noted that in the production environment the production operators are not able to make self-directed decisions e.g. related to the feasible order of the jobs. This is partly due to the lack of real time information transparency (IT system issue) but also lack of understanding of the whole. Therefore, making the factory floor workers to participate to such facilitated sessions could be beneficial for the company to enhance the production to flow and to reduce lead time.

The presented methods could be combined so, that the production development needs are analysed with the DRP method and then, as part of the change process, the earlier production changes are analysed with lessons learned method to find out the most effective ways of implementing changes. However, the methods require a supporting organizational culture, which may not be present in the small manufacturing companies at the moment. Also, the DRP method might be too complex for a small manufacturing company which does not have own product development functions. Additionally, the methods do not directly enhance the availability of production related information needed for design for manufacturing, design for assembly and design for assembly automation.


Fatih Karakoyun
email: fatih.karakoyun@epfl.ch

Dimitris Kiritsis
email: dimitris.kiritsis@epfl.ch

A Study on Social Assessment in Holistic Lifecycle Management

Keywords: Sustainability assessment, holistic lifecycle management, S-LCA

Sustainable manufacturing has been focus of the industry for some time. Due to the holistic nature of sustainability not only the manufacturing processes but the whole life cycle and the environmental, economic and social aspects of the product should be taken in to account. In order to leverage from the concept of sustainability it is necessary to involve it in decision making process in the supply chain. It is essential to have an evaluation procedure so as to involve it in decision making which should be capable of assessing economic, environmental and social performance of the product. Unfortunately the social dimension of sustainability is the least developed and even neglected because it is difficult to evaluate due to its quantitative and subjective nature. The social aspects of holistic life cycle approach will be presented in this paper.

Introduction

Several definitions of sustainability have been proposed, over time. The World Commission on Environment and Development declaration [6] reads: "sustainable development is a process of change in which the exploitation of resources, the direction of investments, the orientation of technological development, and institutional change are made consistent with the future as well as present needs" [START_REF] Jovane | The incoming global technological and industrial revolution towards competitive sustainable manufacturing[END_REF].

There is now a well-recognized need for achieving overall sustainability in industrial activities, arising due to several established and emerging causes: diminishing non-renewable resources, stricter regulations related to environment and occupational safety/health, increasing consumer preference for environmentally-friendly products, etc. In particular, the manufacturing sector, which lies at the core of industrial economies, must be made sustainable in order to preserve the high standard of living achieved by industrialized societies and to enable developing societies to achieve the same standard of living sustainably [START_REF] Jayal | Sustainable manufacturing: Modeling and optimization challenges at the product, process and system levels[END_REF].

Sustainable manufacturing must respond to; economic challenges, by producing wealth and new services ensuring development and competitiveness through time; environmental challenges, by promoting minimal use of natural resources (in particu-lar non-renewable) and managing them in the best possible way while reducing environmental impact; social challenges, by promoting social development and improved quality of life through renewed quality of wealth and jobs [START_REF] Jovane | The incoming global technological and industrial revolution towards competitive sustainable manufacturing[END_REF].

The problem of finding a balance between the economic, social, and environmental values of human development is now at the heart of the debate that involves men of culture, men of faith, economists and politicians, who are working together to tackle the problems of globalization. At the center is a reflection of the responsibilities of politics and economics that is related to the imbalance of the world's social and economic order, putting in danger the ultimate goal for a civil society which is to guarantee an acceptable human condition that may be 'shared', starting from the common membership of a network of international relationship that is central to our age [START_REF] Pepe | Corporate values in global supply chains. Symphonya, Emerging Issues in Management[END_REF].

In the last few decades, ethics in business activities has become part of the wider concept of CSR, which is developing from a good idea to a critical part of business activity. CSR has become important in terms of consumers' perceptions, so it has become important for all consumer-oriented firms. Corporate social responsibility (CSR) is a broader concept and not limited to supply chains, but to the companies' overall treatment of human beings and the environment. Broadly speaking, the construct of CSR as we know it today has two main characteristics. Firstly, it describes the relationship between business and the larger society. Secondly, it refers to a company's voluntary activities in the area of environmental and social issues [START_REF] Andersen | Corporate social responsibility in global supply chains[END_REF].

Usually, studies of supply chain management have concentrated on economic issues, such as finding ways to minimize the operational costs or to maximize profits. Sustainable supply chain management (SSCM) may be defined as the strategic, transparent integration and achievement of an organization's social, environmental, and economic goals in the systemic coordination of key inter-organizational business processes for improving the long-term economic performance of an individual company and its supply chain [START_REF] Carter | A framework of sustainable supply chain management: moving toward new theory[END_REF].

All over the world, companies make business decisions every day which affect people and environment, directly through their own operations, or indirectly through the value chain of their business. Increasingly, these companies are confronted with questions, e.g. from customers, consumer organisations and other NGOs, regarding their social performance. Society's expectations to companies to assume a wider responsibility for the social impacts of their business activities is a challenge that has been accepted by companies that wish to conduct business in a more responsible way. Many companies, thus, see themselves in need of a tool which can help them make informed decisions about their social impacts throughout the life cycle of their products [START_REF] Dreyer | A Framework for Social Life Cycle Impact Assessment[END_REF].

Holistic life cycle approach is an evaluation methodology which takes into account the whole life cycle of a product and generates performance characteristics (technical, environmental, economic and social) of a product or product system. The life cycle data is collected from all the actors of value chain and transformed into performance characteristics, which may further be used for decision making. The social aspects of the evaluation procedure are presented in this paper.

2

State of the art (Social life cycle assessment)

Social sustainability sees the development of society as a way of ensuring the participation of all members of society. This involves creating a balance between social forces with a view to achieving a livable society that is sustainable in the long term. As regards training, this means, for example, offering equal opportunities when it comes to accessing learning content irrespective of the geographical location of individual members of society. Manufacturing processes in mass production require workers who have an elementary education and need additional customized training programs that are independent of specific manufacturers and products [START_REF] Marxer | Sustainable Manufacturing Using a Global Education Concept for Coordinate Metrology with a Blended Learning Approach[END_REF]).

The technical system produces many effects (positive and negative) upon human well-being, which are experienced as social impacts by stakeholders (for instance, workers, consumers, local society, etc.) involved in the life cycle. Assigning these effects to one functional unit highlights the balance between the advantages (the units of service provided) and often the drawbacks (for example, quantities of health destroyed).

Social impact refers to consequences caused by activities corresponding to various stakeholders. As far as social impacts are concerned, the consequences may be derived from three dimensions: behaviors (specific behavior/ decision) social-economic processes (the socio-economic decision e.g. investment decision) and capitals (human, social, cultural context) [START_REF] Sanchez Ramirez | Social life cycle assessment: Methodological and implementation issues[END_REF].

When referring to the causes of social impacts, this generally implies three dimensions behaviors (social impacts are those caused by a specific behavior), socioeconomic processes (social impacts are the downstream effect of socio-economic decisions), and capitals (social impacts relate to the original context (attributes possessed by an individual, a group, a society e.g., education level) [START_REF] Benoît | Guidelines for social life cycle assessment of products[END_REF].

Those three dimensions are not exclusive and have dynamic relationships: socioeconomic processes have effects on behavior that may also be rooted in the attributes possessed by an individual or a group. Since the social impacts are often perceived as being very complex and subjective, it is not recommended to define attributes of relationships unilaterally and from there define a set of related indicators isolated from the stakeholder context. As for environmental impacts (cf. the doubts expressed by the non-believers of human-induced climate change), defining social impact categories needs to go through a subjective and inter-subjective process, preferably at the international level [START_REF] Benoît | Guidelines for social life cycle assessment of products[END_REF].

The methods available for working with social aspects in the supply chain include stand-alone tools as well as guidelines and standards. The difference between tools and standards are not clear-cut, and either or could be used as point of departure for improved social performance. The most established method is social impact assessment, but as the focus on social impacts within business (and within society at large) has increased over the last few years, so has the number of methods for assessing, reporting and improving performance with regard to these impacts. The most important methods are; Social Impact Assessment, Social Accountability 8000 Standard, The Global Reporting Initiative, UN Global Compact, Social Life Cycle Assessment of Products, ISO 26000: Guidance for social responsibility (Palme 2011).

A social and socio-economic Life Cycle Assessment (S-LCA) is a social impact (and potential impact) assessment technique that aims to assess the social and socioeconomic aspects of products and their potential positive and negative impacts along their life cycle. It is stated that: 'The ultimate objective for conducting an SLCA is to promote improvement of social conditions and of the overall socio-economic performance of a product throughout its life cycle for all of its stakeholders'. Thus, according to this statement, SLCA should be developed in such a way that its use in some way creates a more socially beneficial situation for the stakeholders in the product life cycle [START_REF] Jørgensen | Addressing the effect of social life cycle assessments[END_REF].

S-LCA allows increasing knowledge, providing information for decision makers and promoting improvement of social conditions in product life cycles (Benoit et al., 2010). S-LCA helps inform incremental improvements but does not in itself provide a breakthrough solution for sustainable consumption and sustainable living. Those topics go well beyond the scope of the tool. S-LCA provides information on social and socio-economic aspects for decision making, instigating dialogue on the social and socio-economic aspects of production and consumption, in the prospect to improve performance of organizations and ultimately the well-being of stakeholders [START_REF] Benoît | Guidelines for social life cycle assessment of products[END_REF].

One important feature to be emphasized is that social impact is not directly linked to the production chain process of a product, it is not determined by physical flows, unlike the E-LCA, but from the way it interacts with the stakeholders. Therefore, the identification of all stakeholders involved on the product/service life cycle is a fundamental issue when performing an S-LCA (Sanchez Ramirez & Petti 2011).

Social Evaluation in Holistic life cycle approach

Holistic life cycle approach is a product evaluation procedure, which takes into account the whole life cycle of the product (material extraction, production, use and disposal) and provides performance characteristics (technical, environmental, economic and social) in order to have a broad perspective about the all activities of the product and processes. HLA may provide valuable information in order to be used in decision making and reduces the risk of decision making.

LCA, LCC and S-LCA are combined in HLA. The methodologies involved in HLA have life cycle perspective thus avoids burden shifting. Since all the activities through the life cycle of the product is taken into account, their performances may be evaluated separately.

LCA and LCC is performed based on the unit processes concerning the product, however S-LCA is performed based on the interaction of the life cycle actors with the stakeholders around them. In order to combine LCA, LCC and S-LCA, the three methodologies should have the same system boundaries. The same LCI could be used for LCA and LCC, since the data needed for both methodologies are quantitative. LCI for S-LCA contains quantitative and qualitative data, and also data regarding to the stakeholders out of the value chain. A separate LCI should be prepared for S-LCA. Additionally, in some conditions the system boundaries for S-LCA should be extended in order to involve the missing stakeholders.

Social performance characteristics are evaluated by social life cycle assessment (S-LCA). The guideline provided by UNEP are followed in S-LCA. Figure 1 illustrates the assessment framework for S-LCA.

Figure 1 Assessment system from categories to unit of measurement

A stakeholder category is a cluster of stakeholders that are expected to have shared interests due to their similar relationship to the investigated product systems. Additional categories of stakeholders or further differentiations or subgroups can be added in order to have more detailed and precise subcategories of a specific stakeholder of concern may be identified [START_REF] Benoît | Guidelines for social life cycle assessment of products[END_REF]. In spite the fact that, the environmental and economic aspects are related to the life cycle actor itself, social impacts may be occur in five main stakeholder categories presented in Figure 1, at each life cycle actors location. Additionally, it is necessary to note that the scope of S-LCA should be defined carefully because it will determine the number of companies that will be involved and contributed in the evaluation, and the amount of data that should be handled.

The aggregation of the sub categories is another issue since there will be qualitative and quantitative data will be collected during the study. This means the performance characteristics will also be both quantitative and qualitative. Figure 2 shows the subcategories for S-LCA. The first think to do is to decide on the subcategories that will be included and excluded in the assessment and justify the decision. Second step is to collect inventory data concerning the sub categories. And finally, aggregate the data in a way that the alternative scenarios may be evaluated.

4

Case Study (SUWAS)

The SuWAS project (Sustainable Waste Management Strategy for Green Printing Industry Business) is an ECO-INNOVERA project aiming at the economic, social and environmental assessment of the deployment of a new technology at EU scale. This technology is patented and owned by the University of Alicante. The patent concerns the process to recover the waste-ink components of the (solvent-based) flexographic printing industry to generate secondary products. It is an alternative to the current costly (120 Euros/ton) mandatory incineration (hazardous waste). A general overview of the system under study is shown in Figure 3. This study focuses on the end-of-life of waste-ink from the flexographic industry, including waste collection and treatment. This is a 'gate to grave' approach which does not consider the whole life cycle of the product (this would be a cradle to grave approach). The upstream life cycle stages of ink (production and use phases) have not been included into the study since; a) ink is considered as a waste, b) they are similar between the compared scenarios and would not provide any insights for the analysis.

The subcategories included in the social evaluation are shown in We cannot adhere to the system boundaries of the LCA and LCC study, because the recycling of the waste ink will reduce the need for imported ink from China. In this case, it is necessary to extend the system boundaries and include the ink production stage in the assessment.

Three scenarios were evaluated for processing waste ink; (1) it is incinerated in the waste disposal company, it is recycled in the printing facility, and it is recycled in the waste ink recycling company. These scenarios are evaluated in the region of UA in Spain, and EU level deployment of the process. Some of the performance characteristics for workers and the necessary information in order to evaluate them are shown in the table below. Comparison of the performance characteristics for three scenarios are illustrated in Figure 4. The workers in the second scenario have better conditions than the other scenarios, since they have better salary then the others, the working hours seem to be fair, and it offers a safer environment to work. However, it should be noted that the man/hour cost is higher in this scenario. In economic point of view, this scenario exhibits a higher labor cost, but the share of the labor cost among the other LCC items should be identified.

Conclusion

Appraisal of sustainability requires a holistic approach that takes into account the whole life cycle of the product system and combination of a number of methodologies that evaluates the economic, environmental and social aspects of sustainability. Social sustainability which is one of the three pillars of sustainability, has been discarded not only because it is difficult to evaluate but also environmental and economic aspects have gained more attention in the last decade. Social-LCA aims to assess the social and socio-economic aspects of products and their potential positive and negative impacts along their life cycle in order to promote improvement of social conditions and overall socio-economic performance of a product for all its stakeholders. Stakeholders and subcategories should be determined carefully and elaborately so as to be able to evaluate the social performance of the product implicitly.

Figure 3

 3 Figure 3 Overview of the system, with outputs

Figure 4

 4 Figure 4 Comparison of performance characteristics for Workers

Table

  .

Table 1

 1 Subcategories selected for SUWAS

	• Worker	• Safe and healthy living conditions
	• Fair salary CFS	• Local employment
	• Working hours CWH	• Society
	• Health and safety CHS	• Public commitment to sustainability issues
	• Consumer	• Contribution to economic development
	• Health and safety	• Technology development
	• End of life responsibility	• Value chain actors
	• Local community	• Promoting social responsibility
	• Access to material resources	• Supplier relationships
	• Delocalization and migration

Table 2

 2 Performance characteristics for workers

Acknowledgements. The authors would like to express our deep gratitude to all partners of SUWAS project and ECO-INNOVERA consortium.


Naghmeh Taghavi

Ilaria Barletta

Cecilia Berlin
email: cecilia.berlin@chalmers.se

Social Implications of Introducing Innovative Technology into a Product-Service System: the Case of a Waste-Grading Machine in Electronic Waste Management

Keywords: Social sustainability, Key Performance Indicators, Product-Service systems, Electronic Waste Management, Social Impacts

This paper examines the social implications of introducing a new technology into the product-service system (PSS) of electronic waste management (EWM). Using a previously established set of social sustainability key performance indicators (KPIs) targeting the operations level (i.e. impacts on EWM operators), social implications are examined in a case where a specific innovative new technology is introduced to replace manual sorting of e-waste into re-use, refurbish and recycle fractions. The social sustainability KPIs were applied to the case as a structured interview guide. The results showed that the KPI framework provided a good basis for examining the social impacts and also stimulated discussions about potential business impacts based on the human resources in the system. The framework showed that the implementation supported proactive social sustainability, but some additional conditions need to be addressed by the customer organization to make sure that potential risks (identified in the interview) are mitigated.

Introduction

The last few decades have seen an increased focus on the concept of sustainable development [START_REF] Brundtland | Report of the World Commission on environment and development:" our common future[END_REF] in operations [START_REF] Elkington | Cannibals with forks: the triple bottom line of twenty first century business[END_REF] due to global restrictions, legislations and customers' awareness of sustainability together with a global competitive environment. Considerable progress has been made with the environmental aspect, e.g. by implementing new "greener" technologies. Among the three sustainability "pillars", i.e. environmental, economic and social, the aspect of social sustainability has been widely acknowledged as the least developed [START_REF] Vallance | What is social sustainability? A clarification of concepts[END_REF][START_REF] Collins | Sustainability practices: trends in New Zealand businesses[END_REF][START_REF] Omann | Assessing social sustainability[END_REF], especially in the operations context. The literature provides a very broad scope for the social aspect ranging from a global to a local scale, sometimes without distinguishing that achieving social sustainability may require different approaches in developed and developing countries. To this end, solutions are sought both in the high-level strategic sense and the lower-level technological implementation sense. As a result, it has traditionally been difficult to define an operative scope for manufacturing companies aspiring to improve social sustainability on a factory level, although a distinction between "traditional" and "emergent" aspects of social sustainability has appeared in later years [START_REF] Colantonio | Social sustainability: exploring the linkages between research, policy and practice[END_REF]. Some emergent social sustainability concerns in developed countries include demographic trends like aging populations with shortage of qualified labor as a result, and the increased importance of making manufacturing a more attractive future workplace option to attract new generations of workers [START_REF] Berlin | Social sustainability challenges for european manufacturing industry: Attract, recruit and sustain[END_REF]. Alongside this, many parallel developments drive incentives to further automate manufacturing processes, particularly those that are hazardous, monotonous or physically strenuous.

Overall, social impacts on operators at factory level resulting from new automation technologies and business solutions, remains an important research topic.

There are several reasons for a manufacturing company to adopt product-service systems [START_REF] Mont | Clarifying the concept of product-service system[END_REF]. These can influence sustainable development by extending producers' "involvement and responsibility to phases in the life cycle, which are usually outside the traditional buyer-seller relationship, such as take back, recovery, reuse and refurbishment and remanufacturing." [START_REF] Mont | Clarifying the concept of product-service system[END_REF]. Regarding environmental and economical sustainability, an increasing industrial emphasis is being placed on the "end-of-life" (EoL) stage of consumer products. In some countries, producers of various consumer goods are tasked with the responsibility of taking care of the products once they have left the hands of customers and become waste [9]. Within the industry context, previous research efforts ( [START_REF] Mont | Clarifying the concept of product-service system[END_REF], [START_REF] Aurich | Life cycle oriented design of technical Product-Service Systems[END_REF]) have addressed the environmental and economic impacts of implementing PSS, whereas other studies like [START_REF] Peruzzini | Design for Sustainability of Product-Service Systems in the Extended Enterprise[END_REF], [START_REF] Armstrong | Sustainable product-service systems for clothing: exploring consumer perceptions of consumption alternatives in Finland[END_REF] have considered the societal impacts of it but without addressing implications for the factory operators specifically.

One particularly interesting form of PSS is Electronic Waste Management (EWM), a burgeoning industry that turns electronic waste from an environmental threat into a resource for society. According to [START_REF] Barletta | Fostering sustainable electronic waste management through intelligent sorting equipment: Submitted to the IEEE CASE 2015 Special Session[END_REF], "today e-waste sorting is performed mostly by humans, as up to now they are the most flexible and self-learning resource available.

Operators not properly equipped by protective devices get exposed to hazardous substances from electronics' segregation". However, technological solutions for waste sorting and grading are on the rise. Apart from the advantage that automating e-waste sorting can reduce human operators' unnecessary exposure to hazardous substances leaking out of e-waste materials, it remains to be examined what social impacts such a development can have on human operators at factory level. Therefore, this study aims to explore the implications of social sustainability key performance indicators in a specific case of introducing a new technology (in the form of waste sorting equipment) into an EWM PSS. This is examined by using a framework of previously established social sustainability key performance indicators (KPIs) as a starting point [START_REF] Taghavi | Social Sustainability KPIs in Operations Management: A Gap between the Reactive and the Proactive Stance[END_REF].

Theoretical framework

Product-service systems (PSS)

PSS is a term that has been defined as "a marketable set of products and services capable of jointly fulfilling a user's need. The product/service ratio in this set can vary, either in terms of function fulfilment or economic value" [START_REF] Goedkoop | Product service systems, ecological and economic basics[END_REF]. Various authors have proposed different classifications of PSS [START_REF] Goedkoop | Product service systems, ecological and economic basics[END_REF][START_REF] Zaring | Creating eco-efficient producer services[END_REF][START_REF] Tukker | Eight types of product-service system: eight ways to sustainability? Experiences from SusProNet[END_REF], of which the three most distinct classification categories are product-related services, use-oriented services and result-oriented services. According to [START_REF] Mont | Clarifying the concept of product-service system[END_REF], from a company perspective adopting a PSS can add to products' value, base growth strategy on innovation, improve the company/ consumer relationship, improve the total value for the customer by extending products' life-cycle, extending products' function through upgrading and refurbishment and also making the product useful after its life cycle ends through recycling or reuse, and also helps the company implement take-back legislations.

Socially sustainable work systems

There is no wholly agreed-upon definition in literature of what constitutes a socially sustainable work system, but [START_REF] Eijnatten | From intensive to sustainable work systems: The quest for a new paradigm of work[END_REF] defines it as a system that has achieved a high level in three main aspects: quality of work, quality of the organization and the quality of connections with the environment. To achieve a socially sustainable manufacturing work system that can combat the aforementioned demographic challenge, it should be able to meet the needs of both current and future employees. To that end, it should be able to attract different societal groups as potential workers, i.e. younger, elderly, women, disabled and in general support greater diversity. In [START_REF] Taghavi | Social Sustainability KPIs in Operations Management: A Gap between the Reactive and the Proactive Stance[END_REF], [START_REF] Adams | Mapping the Current Social Sustainability Practices of the European Manufacturing Industry[END_REF] the authors have used the key aspects of socially successful work systems from literature to develop a framework of social sustainability related KPIs, presented in Table 1. Fair pay [START_REF] Initiative | G4 Sustainability Reporting Guidelines. Reporting Principles and Standard Disclosures, Global Reporting Initiative[END_REF], [START_REF] Joung | Categorization of indicators for sustainable manufacturing[END_REF] Personal development, Talent management and career development [START_REF] Berlin | Social sustainability challenges for european manufacturing industry: Attract, recruit and sustain[END_REF], [START_REF] Eijnatten | From intensive to sustainable work systems: The quest for a new paradigm of work[END_REF], [START_REF] Initiative | G4 Sustainability Reporting Guidelines. Reporting Principles and Standard Disclosures, Global Reporting Initiative[END_REF], [START_REF] Backes-Gellner | Avoiding labor shortages by employer signaling: on the importance of good work climate and labor relations[END_REF][START_REF] Boswell | Individual job--choice decisions and the impact of job attributes and recruitment practices: A longitudinal field study[END_REF][START_REF] Lewis | Lean production and sustainable competitive advantage[END_REF][START_REF] Brito | Towards a sustainable fashion retail supply chain in Europe: organisation and performance[END_REF][START_REF] Rothwell | Career planning and succession management: developing your organization's talent--for today and tomorrow[END_REF] Work design

• Challenging & stimulating job • Participation • Empowerment [7]
, [START_REF] Eijnatten | From intensive to sustainable work systems: The quest for a new paradigm of work[END_REF], [START_REF] Backes-Gellner | Avoiding labor shortages by employer signaling: on the importance of good work climate and labor relations[END_REF][START_REF] Boswell | Individual job--choice decisions and the impact of job attributes and recruitment practices: A longitudinal field study[END_REF][START_REF] Lewis | Lean production and sustainable competitive advantage[END_REF], [START_REF] Basmer | Open Production: Chances for Social Sustainability in Manufacturing[END_REF], [START_REF] Veleva | Indicators of sustainable production: framework and methodology[END_REF] Work-life balance [START_REF] Boswell | Individual job--choice decisions and the impact of job attributes and recruitment practices: A longitudinal field study[END_REF], [START_REF] Hill | Exploring the relationship of workplace flexibility, gender, and life stage to family-to-work conflict, and stress and burnout[END_REF][START_REF] Pfeffer | Building sustainable organizations: The human factor[END_REF][START_REF] Kovach | What motivates employees? Workers and supervisors give different answers[END_REF][START_REF] Bourne | Designing, implementing and updating performance measurement systems[END_REF][START_REF] Harrington | Career management & work-life integration: using selfassessment to navigate contemporary careers[END_REF] Employee Turnover and Satisfaction management [START_REF] Boswell | Individual job--choice decisions and the impact of job attributes and recruitment practices: A longitudinal field study[END_REF], [START_REF] Barling | High-quality work, job satisfaction, and occupational injuries[END_REF][START_REF] Azapagic | Developing a framework for sustainable development indicators for the mining and minerals industry[END_REF][START_REF] Krajnc | Indicators of sustainable production[END_REF] Job Security [START_REF] Backes-Gellner | Avoiding labor shortages by employer signaling: on the importance of good work climate and labor relations[END_REF] 3 Method and case description

Method

The overall research approach for this paper has been to perform a qualitative case study, incorporating a literature study, observations and interviews as we strived to explain a complex phenomenon under investigation [START_REF] Meredith | Building operations management theory through case and field research[END_REF]. General data regarding the EWM case were collected mainly through semi-and unstructured interviews and study visits to the EWM facility. After the initial studies the aforementioned framework of social sustainability KPIs from [START_REF] Taghavi | Social Sustainability KPIs in Operations Management: A Gap between the Reactive and the Proactive Stance[END_REF] was employed as a structured interview with a company representative who elaborated specific impacts on human stakeholders.

Case description

EWM systems challenge the ideas of traditional business models, both by adding value to something previously considered worthless, and in this particular case, by the fact that their system components (equipment and personnel) are accessible partially as a product and as a service. This case studies the REFIND company, which has developed and introduced a new automation technology called the E-grader to sort, grade and recycle e-waste using optical sorting [START_REF]REFIND technologies[END_REF]. The E-grader is available both as an equipment for rent and as a service where customers (e.g. retailers of electronic consumer goods) send spent e-waste to REFINDs facility for sorting and grading into useable "fractions". In other words, the E-grader itself is a PSS being implemented into another PSS (the EWM system) in a "nested" fashion. According to [START_REF] Barletta | Fostering sustainable electronic waste management through intelligent sorting equipment: Submitted to the IEEE CASE 2015 Special Session[END_REF] the Egrader is able to distinguish much more rapidly than human workers which products are suitable to reuse, refurbish or recycle. During waste sorting, data regarding the products' type, brand, model, year to market etc. are recorded automatically. Other data fields can be added based on the companies' specific needs. By contrast, today's manual e-waste sorting cannot store workers' knowledge and WEEE items' data into a structured data management system.

Fig. 1. The E-grader, an automatic equipment solution for e-waste sorting and grading developed by [START_REF]REFIND technologies[END_REF].

The environmental and economic aspects of the E-grader were the main drivers for its introduction as a solution for EWM systems. Some major motivations for automating the extraction of re-purposable fractions from e-waste are described in greater detail in [START_REF] Barletta | Prerequisites for a high-level framework to design sustainable plants in the e-waste supply chain[END_REF] and include: the presence of valuable and rare earth materials in the e-waste products (e.g. copper, iron, steel, gold, silver and platinum); minimizing human and environmental exposure to hazardous substances that can damage health; and increased manufacturer responsibility for addressing the end-of-life (EOL) phase of their products.

Findings and analysis

This section presents and qualitatively analyses interview data from the case company. Each topic heading reflects its corresponding indicator from Table 1, and words in cursive signal the relationship of findings to specific KPIs.

Labour code of conduct

For the sake of their health and safety, operators need to be carefully protected from exposure to dirt and toxic substances, which are typical for the manual electronics' segregation process of e-waste handling. Introducing the E-grader to the system will reduce the exposure of operators to acid-resistant substances. However, the operators need to be prepared and trained in terms of safety procedures and health issues regarding the new equipment, e.g. safety implications from loading, unloading, turning it on, etc. These tasks are not considered to be high-risk operations in general, but if the operators are not well-trained, incidents and accidents may occur. The effect on absenteeism numbers is two-fold. The rate of absenteeism related to health and safety issues will depend on the training level of operators as discussed above; numbers might even increase if training is not sufficient and accidents occur. However, since the new technology will affect the employees' satisfaction level and happiness and work-life balance, it could also reduce absenteeism. Due to the new technology's positive impacts on process efficiency, the company margin is expected to increase. Moreover the operators will perform higher-skilled tasks. Therefore, the operators' salary and the monetary incentives can be affected in positive way.

Personal development, talent management and career development

As described in 3.2, adding the E-grader to the EWM process results in knowledge and intelligence being added to the sorting process. This can unlock more opportunities for personal development of the people working with the system, because the system stores and aggregates statistics on the sorted fractions. Once the data and different dimensions of it become accessible, the operators can explore the dataset, understand the statistics, make forecasts and "control" their cash flows. When operators "use their brain" as opposed to simply handling waste, managers have an opportunity for talent management by recognizing good ideas from workers and incentivizing them.

Work design

Currently the manual tasks performed by operators are monotonous tasks. Introducing the E-grader to the system opens up for more diverse tasks and therefore more possibilities of job rotations. Moreover, people that work with the data management part are called to understand these data and map them properly. Therefore the job becomes more stimulating for them compared to pure materials handling. At the same time, the operators may experience more participation and empowerment as they are expected to independently come up with ideas, reports, findings and conclusions based on used electronics statistics. As the system adapts to new specifics within regulations and recycling schemes or market changes, operators will also learn new skills and will be personally developed, which can lead to more satisfied employees.

4.4

Work-Life balance

The implementation of the E-grader can affect work-life balance due to the shift in the operators' responsibilities, but will also make some of the tasks location-independent and self-organised, particularly the tasks which pertain to analysing the data. This means that operators could take care of some non-loading-related tasks remotely, decreasing the need to spend time at the sorting facility, which will affect the worklife balance.

Employee turnover and satisfaction management

Right now manual e-waste handling suffers from very huge turnovers, not only due to the menial work in itself but also due to the very low salaries. Introducing the Egrader and new tasks is expected to reduce the turnover because of higher job satisfaction and higher salaries caused by more profit.

Job security

Implementing a technology that can replace several operators might affect the number of jobs in a negative way. On the other hand, as operators become more knowledgeable they will become more important assets for the company. Also, since the new technology can make the company more profitable, these two impacts can secure the operators' jobs in a positive and more sustainable way.

Discussion & Conclusion

Methodical approaches to examining social impacts of PSS remain scarce, but this case study indicates some promising first steps towards their development. The Social sustainability KPIs suggested by [START_REF] Taghavi | Social Sustainability KPIs in Operations Management: A Gap between the Reactive and the Proactive Stance[END_REF] made an efficient inquiry possible into social impacts of introducing a technological innovation to an EWM PSS. In this particular case, the framework clearly highlighted the advantages and disadvantages for operators of implementing the technology. This case also suggests that this PSS may have potential to support proactive aspects of social sustainability, something that is argued as very important in [START_REF] Taghavi | Social Sustainability KPIs in Operations Management: A Gap between the Reactive and the Proactive Stance[END_REF]. Based on the interview results, the authors note that some additional conditions, that the technology itself cannot not provide, need to be secured by the organization implementing the E-grader, in order to ensure a socially sustainable implementation:

• Education and training must be provided to employees using the equipment to prevent injuries and to make sure that the aggregated data is exploited well • Workers must be made aware that new responsibilities are expected of them, such as analyzing the data and coming up with new ideas, in order to gain the advantage of more varied and meaningful work, increased participation and empowerment • Tradeoffs between number of job opportunities and meaningful work content must be managed by companies. In conclusion, the previously established list of Social Sustainability KPIs provided a helpful framework for inquiring about social implications in the implementation of a technological innovation in an EWM PSS, as demonstrated in this case.

Table 1 .

 1 Key

	Key performance indicators	References
	Labour code of conduct:
	•	Occupational health and safety
	•	No of absenteeism/ fatalities
	•	No of incidents/ high risks related to occupation
	•

performance indicators of socially sustainable operations (adapted from

[START_REF] Armstrong | Sustainable product-service systems for clothing: exploring consumer perceptions of consumption alternatives in Finland[END_REF]

&

[START_REF] Tukker | Eight types of product-service system: eight ways to sustainability? Experiences from SusProNet[END_REF]

)

Acknowledgements. The authors warmly thank Hans Eric Melin, interviewed over the proceeding of this study. This work is funded by VINNOVA (Swedish Agency for Innovation Systems) through the WEEE ID project. This work has been carried out within the Sustainable Production Initiative and the Production Area of Advance at Chalmers. The support is gratefully acknowledged.