Designing sustainable work systems: The need for a systems approach

There is a growing discussion concerning sustainability. While this discussion was at first mainly focused on a society level – and sometimes regarding especially environmental problems, one can now see that this topic is of increasing relevance for companies worldwide and even the social dimension of this three pillar approach is gaining more and more importance. This leads to some questions: Is sustainability already a part of human factors thinking or do we have to further develop our discipline? How can we define sustainable work systems? What are the topics we have to consider? Do we need a new systems ergonomics perspective regarding whole value creation chains and a life-cycle perspective concerning products (and work systems)? How can we deal with potential contradictions about social, ecological, and economic goals?     

The investigation and evaluation of work and workplaces

Most workplaces and jobs demonstrate a mis-match in relation to the workers involved with them. To assess this we must measure the work loads, the workplace characteristics, the work performance, the interactions of these with the workers and the consequences for them. Changes are devised as a result of these measures, and insofar as the measures fall short of the comprehensive list above, then the modifications may be sub-optimal as important aspects are not taken into account. The results of the changes, too, need a similar comprehensive assessment.

The paper will follow through the process of investigating industrial workplaces. It will briefly introduce techniques developed for assessing a range of aspects and how they lead to the development of changes. The view of the worker as a total person will be supported by proposals for the combined evaluation of the task, the workplace etc and the state and effects of the social environment, with suggestions for their economic evaluation.     

数控机床加工系统远程在线监测方案设计

本文以数控机床为对象,设计了一个基于网络技术和虚拟仪器技术的数控机床加工系统远程监测系统,并将当前流行的视频监控技术应用到该在线监测系统中来,重点研究了刀具状态的监测方法。     

Design,programming and orchestration of heterogeneous manufacturing systems through VR-powered remote collaboration

Modern manufacturing systems are often composed of a variety of highly customized units and specifically designed manufacturing cells. Optimization of assembly and training of staff requires a series of demo installations and excessive use of costly operational resources. In some cases, components are located at different sites, making the orchestration of the whole system even more difficult.Virtual Reality (VR) collaboration environments offer a solution by enabling high fidelity testing and training of complex manufacturing systems. On the other hand, such platforms are difficult to implement in an engineering perspective, as they are required to provide reliable, standard interfaces towards both robotic components and human operators.The VirCA (Virtual Collaboration Arena) platform is a software framework that supports various means of collaboration through the use of 3D augmented/virtual reality as a communication medium. VirCA offers functions for the high-level interoperability of heterogeneous components in a wide range of domains, spanning from research & development, through remote education to orchestration and management of industrial processes in manufacturing applications. This paper provides an overview of the industrial requirements behind high-fidelity virtual collaboration and demonstrates how the VirCA platform meets these requirements. Use cases are provided to illustrate the usability of the platform.     

Emerging ICT concepts for smart,safe and sustainable industrial systems

This editorial introduces the special issue on Emerging Information and Communication Technology (ICT) concepts for smart, safe and sustainable industrial systems in the Elsevier journal Computers in Industry. The 13 papers in this special issue were selected because of their high quality and also because they propose emerging ICT solutions that address at least one of the three dimensions we suggest as basic requirements to design usable future Industrial Systems that must be safe, smart and sustainable. Previous global discussions about the state of the art with regard to the topic of this special issue are provided, as well as exploratory guidelines for future research in this area.     

The design of shift systems

All shift systems have advantages and drawbacks. There is no single ‘optimum shift system’ which can be used in industry or commerce at all work places. However, there are shift systems which are more favourable, and others which are less favourable, in the context of physiological, psychological, and social recommendations for the design of shift systems. This article discusses the following recommendations:

(1) Nightwork should be reduced as much as possible. If this is not possible, quickly rotating shift systems are preferable to slowly rotating ones. Permanent nightwork does not seem to be advisable for the majority of shiftworkers.

(2) Extended workdays (9-12 h) should only be contemplated, if the nature of work and the workload are suitable; the shift system is designed to minimize the accumulation of fatigue; there are adequate arrangements for cover of absentees; overtime will not be added; toxic exposure is limited; and if it is likely that a complete recovery after work and a high acceptance of the working time arrangement are possible.

(3) An early start for the morning shift should be avoided. In all shiftsystems flexible working time arrangements- are realizable. The highest flexibility is possible in ‘time autonomous groups’.

(4) Quick changeovers (e.g., from night to afternoon shift at the same day or from afternoon to morning shift) must be avoided. The number of consecutive working days should be limited to 5-7 days. Every shift system should include some free weekends with at least two successive full days off.

(5) The forward rotation of shifts (phase delay, clockwise rotation) would seem to be recommendable at least in continuous shift systems.

Besides the design of a shift system, implementation strategy is of particular importance for the acceptance of the shift system.     

Study on the communication method for chaotic encryption in remote monitoring systems

In chaotic cryptosystems, it is recognized that using (very) high dimensional chaotic attractors for encrypting a given message may improve the privacy of chaotic encoding. In this paper, we study a kind of hyperchaotic systems by using some classical methods. The results show that besides the high dimension, the sub-Nyquist sampling interval (SI) is also an important factor that can improve the security of the chaotic cryptosystems. We use the method of time series analysis to verify the results.     

Bandwidth reduction for remote navigation systems through view prediction and progressive transmission

Remote navigation systems, such as exploration of virtual 3D worlds or remote surgery, usually require higher bandwidth than the Internet connection commonly available at home. In this paper, we explore a set of techniques to reduce the bandwidth required by these applications. Our system consists of a client PC equipped with a graphics card, and a remote high-end server. The server hosts the remote environment and does the actual rendering of the scenes for several clients, and the new image is passed to them. This scheme is suitable when the data has a copyright or when its size may exceed the rendering capabilities of the client. The general scheme is the following: each time the position changes, the new view is predicted by both the client and the server and the difference information between the predicted view and the correct one is sent to the client. To reduce bandwidth we can improve the prediction method, and the transmission system. We present here two groups of techniques: First, a set of lossless methods which achieve reductions of up to a 9:1 ratio. These are a combination of a two-level forward warping, that takes advantage of spatial coherence, and a masking method, which allows to transmit only the information that really needs to be updated. Second, a set of lossy methods suitable for very low bandwidth environments which involve both progressive transmission and image reuse. They consider relevant parameters such as the number of pixels, the amount of information they provide, and their colour deviation in order to create a strategy for prioritizing the information transmission. This system allows to improve up to an additional 4:1 ratio. The quality of the generated images is very high, and often indistinguishable from the correct ones.     

Challenges to remote emergency decision-making for disasters or Homeland Security

New technology allows information gathering and collaboration across information networks that would be of benefit to emergency response. In a Homeland Security Exercise we compared the utility of fixed and mobile video and high quality still images on remote expert decision-making. Sixteen experts situated in three countries viewed and seven evaluated events of the exercise assisted by audio commentary of local knowledge experts. They evaluated the usefulness of black and white (B/W) compared to color images, fixed fast video versus slow video and still images. Technical difficulties interrupted image transmission to one remote site for half the Exercise. However, the images were found useful, color more so than B/W, mobile more so than fixed. The combination of still images and video was best. Playback of recorded images was especially useful for remote evaluation and decision-making. Improved reliability for these imaging technologies could improve shared awareness and large-scale coordination for Homeland Security events.     

Carpeno: interfacing remote collaborative virtual environments with table-top interaction

Creativity is enhanced by communication and collaboration. Thus, the increasing number of distributed creative tasks requires better support from computer-mediated communication and collaborative tools. In this paper we introduce “Carpeno”, a new system for facilitating intuitive face-to-face and remote collaboration on creative tasks. Normally the most popular and efficient way for people to collaborate is face-to-face, sitting around a table. Computer augmented surface environments, in particular interactive table-top environments, are increasingly used to support face-to-face meetings. They help co-located teams to develop new ideas by facilitating the presentation, manipulation, and exchange of shared digital documents displayed on the table-top surface. Users can see each other at the same time as the information they are talking about. In this way the task space and communication space can be brought together in a more natural and intuitive way. The discussion of digital content is redirected from a computer screen, back to a table where people can gather around. In contrast, collaborative virtual environments (CVE) are used to support remote collaboration. They frequently create familiar discussion scenarios for remote interlocutors by utilizing room metaphors. Here, virtual avatars and table metaphors are used, where the participants can get together and communicate with each other in a way that allows behaviour that is as close to face-to-face collaboration as possible. The Carpeno system described here combines table-top interaction with a CVE to support intuitive face-to-face and remote collaboration. This allows for simultaneous co-located and remote collaboration around a common, interactive table.

Software to facilitate remote sensing data access for disease early warning systems

Satellite remote sensing produces an abundance of environmental data that can be used in the study of human health. To support the development of early warning systems for mosquito-borne diseases, we developed an open-source, client-based software application to enable the Epidemiological Applications of Spatial Technologies (EASTWeb). Two major design decisions were full automation of the discovery, retrieval and processing of remote sensing data from multiple sources, and making the system easily modifiable in response to changes in data availability and user needs. Key innovations that helped to achieve these goals were the implementation of a software framework for data downloading and the design of a scheduler that tracks the complex dependencies among multiple data processing tasks and makes the system resilient to external errors. EASTWeb has been successfully applied to support forecasting of West Nile virus outbreaks in the United States and malaria epidemics in the Ethiopian highlands.     

Virtual environments for work, study and leisure

Virtual environments have the potential of adding a new dimension to the concept of a community. In this paper, we describe our work on a text-based virtual environment. Although our focus is on work applications, the environment is equally suited for educational and recreational uses. The paper is presented in the context of the needs of a software development team but can be applied to other work teams as well. Two essential characteristics of successful work teams are good communication and efficient access to project information. Maintaining both of these becomes more and more difficult as the size of the team grows, and gets very difficult when the team is geographically dispersed. We describe a project that could be used to test the hypothesis that a collaborative environment using text-based virtual reality would alleviate these problems by relieving physical separation through virtual proximity. In the first phase of the project, we adapted and extended Jersey, a Smalltalk-based MOO (Multi-user domain Object Oriented) with collaborative virtual environment (CVE) features. On the basis of our experience, we then started designing and implementing MUM, a Multi-Universe MOO. When completed, the more extendable and customisable MUM will provide novel features and encourage developer experimentation. We describe some of MUM's features and our plans for it.     

Automated end-user behaviour assessment tool for remote product and system testing

This paper introduces a virtual reality (VR) based automated end-user behavioural assessment tool required during product and system development process. In the proposed method, while VR is used as a means of interactive system prototype; data collection and analysis are handled by an event based system which is adopted from human–computer interaction and data mining literature. The overall objective of the study is developing an intelligent support system where physical prototyping and the needs for human involvement as instructors, data collectors and analysts during the user assessment studies are eliminated. The proposed method is tested on a product design example using 27 subjects. The experimental results clearly demonstrate the effectiveness of the proposed user assessment tool.     

The work load of warehouse workers in three different working systems

An investigation was conducted in five companies in the distribution branch. These companies were divided into three different working systems, i.e., highly mechanized (HM), moderately mechanized (MM), and slightly mechanized (SM). The three systems differed in logistics and kind of appliances used. The purpose of this study was to compare the three working systems with different degrees of mechanization concerning the time spent on tasks, activities during the working day, postures that occurred, physiological work load, perceived exertion and recovery from work. To investigate the different tasks, activities and working postures, 50 warehouse workers, originating from the three working systems, were observed by means of a direct observation method, called: ‘TRAC’. To investigate the physiological work load the heart rate was recorded continuously during the working day and related to the individually determined relation between heart rate and oxygen uptake. This relation was constructed with the results of a cycle ergometer test done in the laboratory. During lunch and at the end of the working day the warehouse workers filled in a questionnaire concerning their perceived exertion and recovery from work.

In the slightly mechanized system more time was spent with the trunk flexed more than 75° as compared with the other two systems. This posture was very common during lifting of objects, and lifting was done more often in this system than in the other systems. In the MM system the warehouse workers had the highest estimated oxygen uptake and reported the highest perceived exertion at the end of the working day. The workers in the HM system had a shorter working day and had less problems with recovery from work than the workers of the other two systems. Poor working postures like rotation and lateroflexion were commonly found in the HM working system. An important explanation was the difference in time spent driving an electric car. This activity was done mostly in the HM system. In conclusion, the HM system was considered most favourable when it concerned work load and recovery from work. The appliances used in the HM system, and especially the electric car, need to be designed according to ergonomic guidelines to avoid poor working postures.     

Reducing impact of network induced perturbations in remote control systems

The practical realization of remote control systems enforces handling network-induced effects: information transfer and processing delay, delay variability, packet loss and reordering, etc. The paper presents a comparative study of algorithmic methods that assist the control law in achieving higher regulation quality by reducing the detrimental impact of network-related uncertainties. Three popular families of methods, encompassing dynamic delay compensators, multiple control loops, and adjustable sampling rate, are investigated in a common experimental framework that involves a benchmark plant – structurally unstable inverted pendulum-on-a-cart system – and commonly available modules and communication technologies. The method performance in relation to computational footprint and network load is discussed. For the delay with well-established trend of variation the dynamic compensator proves the most efficient option, while more sophisticated methods, involving the exchange of multiple pieces of information, are required under burst packet loss and in stochastic settings with aggravated randomness.     

Macroergonomics: analysis and design of work systems

Attending to the larger system components such as organizational design and management is not novel for ergonomists. In Europe, there has been a strong tradition to investigate ergonomic problems within a holistic, systems context. "Macroergonomics" builds upon this tradition by providing specific methods and tools that yield large-scale results. It is believed that meaningful and large-scale results are needed in today's competitive and turbulent work environments. Macroergonomics is defined, its history is uncovered and focus is given to a key methodology, macroergonomic analysis and design. Case studies are used to validate the method and illustrate that performance results in the 60-90% range can be expected.     

Towards a framework for energy-aware information systems in manufacturing

Environmental concerns, stricter legislation and inflated energy costs, together yield energy efficiency as an important pillar for virtually every industrial sector. Mindful of this challenge, ISs can act as enablers of energy-based management and intelligent decision support. Based on empirical evidence through two case studies combined with the design of a system prototype, this paper identifies those major functionalities that suffice to characterize an IS as ‘energy-aware’ in manufacturing. The functionalities are classified into two broad categories: (a) energy monitoring and (b) energy-aware analytics and are then combined into a high-level architecture. As a prerequisite for deploying such functionalities, this research presents also an approach integrating energy and operational information flows. Beyond that, the technologies that support the real-time and large-scale handling of energy data are provided. Our effort scales up to introduce a generic framework of a case-independent energy-aware IS.     

An innovative integration of fuzzy-logic and systems dynamics in sustainable supplier selection: A case on manufacturing industry

Globally, supply chains compete in a complex and rapidly changing environment. Hence, sustainable supplier selection has become a decisive variable in the firm’s financial success. This requires reliable tools and techniques to select the best sustainable supplier and enhance understanding about how supplier behavior evolves with time. System dynamics (SD) is an approach to investigate the dynamic behavior in which the system status alterations correspond to the system variable changes. Fuzzy logic usually solves the challenges of imprecise data and ambiguous human judgment. Thus, this work presents a novel modeling approach of integrating information on supplier behavior in fuzzy environment with system dynamics simulation modeling technique which results in a more reliable and responsible decision support system. Supplier behavior with respect to relevant sustainability criteria in the past, current and future time horizons were sourced through expert interviews and simulated in Vensim to select the best possible sustainable supplier. Simulation results show that an increase in the rate of investment in sustainability by the different suppliers causes an exponential increase in total sustainability performance of the suppliers. Also, the growth rate of the total performance of suppliers outruns their rate of investment in sustainability after about 12 months. A dynamic multi-criteria decision making model was presented to compare results from the systems dynamics model.     

Collaborative virtual environments: An introductory review of issues and systems

A Collaborative Virtual Environment or CVE is a distributed, virtual reality that is designed to support collaborative activities. As such, CVEs provide a potentially infinite, graphically realised digital landscape within which multiple users can interact with each other and with simple or complex data representations. CVEs are increasingly being used to support collaborative work between geographically separated and between collocated collaborators. CVEs vary in the sophistication of the data and embodiment representations employed and in the level of interactivity supported. It is clear that systems which are intended to support collaborative activities should be designed with explicit consideration of the tasks to be achieved and the intended users' social and cognitive characteristics. In this paper, we detail a number of existing systems and applications, but first discuss the nature of collaborative and cooperative work activities and consider the place of virtual reality systems in supporting such collaborative work. Following this, we discuss some future research directions.