What can the canonical controller in principle tell us?

Given a plant and a desired specification our goal is to construct a controller system which, when interconnected with the plant, yields a system that behaves like the desired specification. We can always construct the canonical controller introduced in van der Schaft (2003) [10]. For linear systems there exists a controller which when interconnected to the plant yields the desired behaviour if and only if the canonical controller is itself one such controller, see Vinjamoor and van der Schaft (2011) [4]. In this paper we extend this result to nonlinear systems. It turns out that one has to look at the canonical controller together with its subsystems. We obtain necessary and sufficient conditions for the existence of a controller for a class of nonlinear systems. We end with examples which show that in certain cases looking at subsystems of the canonical controller also does not suffice.     

Change in area of Ebinur Lake during the 1998–2005 period

Ebinur Lake is located in a typical arid region in the north‐west of China. It is an area with the lowest elevation in the Junggar Basin in the Province of Xinjiang. Recent monitoring indicates that the lake surface area has increased. To obtain a continuous record of the change in lake area, a radiometric analysis of SPOT/VEGETATION (VGT) imagery was carried out based on methodology developed for regional lake area mapping. Two indices, the Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Water Index (NDWI), were selected to identify the water body of Ebinur Lake. The indices are calculated based on the spectral reflectances in the red and near infrared bands of VGT sensor. If the NDVI is less than a critical value (0) and if the NDWI is larger than a critical value (0), the pixel is flagged as a water body. Validation indicates that the methodology to identify water bodies based on multi‐spectral VGT data is applicable in our study area achieving an overall accuracy of 91.4%. Independent monitoring results elicit that the lake surface area was at its lowest in 1998. The yearly average surface area is about 503 km². The lake area increased to 603 km² during 1999. In the period 1999–2001 the area changes are marginal. A large area increase occurred from 2001 to 2002 till the lake area reached a surface area of 791 km². The lake area peaks to 903 km² in 2003 and subsequently decreased to areas of 847 km² in 2004 and 746 km² in 2005. Similar area change dynamics are observed when applying the remote sensing based technique. Seasonally, the typical dynamics elicit a larger surface area in spring and winter and a smaller one during summer.     

How can proteomics elucidate the complexity of multiple sclerosis?

Multiple sclerosis affects more than 2.5 million people worldwide. Although multiple sclerosis was described almost 150 years ago, there are many knowledge gaps regarding its etiology, diagnosis, prognosis, and pathogenesis. Multiple sclerosis is an inflammatory, demyelinating, neurodegenerative disease of the CNS. During the last several decades, experimental models of multiple sclerosis have contributed to our understanding of the inflammatory disease mechanisms and have aided drug testing and development. However, little is known about the neurodegenerative mechanisms that operate during the evolution of the disease. Currently, all therapeutic approaches are primarily based on the inflammatory aspect of the disease. During the last decade, proteomics has emerged as a promising tool for revealing molecular pathways as well as identifying and quantifying differentially expressed proteins. Therefore, proteomics may be used for the discovery of biomarkers, potential drug targets, and new regulatory mechanisms. To date, a considerable number of proteomics studies have been conducted on samples from experimental models and patients with multiple sclerosis. These data form a solid base for further careful analysis and validation.     

What can the history of AI learn from the history of science?

There have been few attempts, so far, to document the history of artificial intelligence. It is argued that the historical sociology of scientific knowledge can provide a broad historiographical approach for the history of AI, particularly as it has proved fruitful within the history of science in recent years. The article shows how the sociology of knowledge can inform and enrich four types of project within the history of AI; organizational history; AI viewed as technology; AI viewed as cognitive science and historical biography. In the latter area the historical treatments of Darwin and Turing are compared to warn against the pitfalls of rational reconstructions of the past.     

What can possibly go wrong? Anticipatory work in space operations

This paper explores how different forms of anticipatory work contribute to reliability in high-risk space operations. It is based on ethnographic field work, participant observation and interviews supplemented with video recordings from a control room responsible for operating a microgravity greenhouse at the International Space Station (ISS). Drawing on examples from different stages of a biological experiment on the ISS, we demonstrate how engineers, researchers and technicians work to anticipate and proactively mitigate possible problems. Space research is expensive and risky. The experiments are planned over the course of many years by a globally distributed network of organizations. Owing to the inaccessibility of the ISS, every trivial detail that could possibly cause a problem is subject to scrutiny. We discuss what we label anticipatory work: practices constituted of an entanglement of cognitive, social and technical elements involved in anticipating and proactively mitigating everything that might go wrong. We show how the nature of anticipatory work changes between planning and the operational phases of an experiment. In the planning phase, operators inscribe their anticipation into technology and procedures. In the operational phase, we show how troubleshooting involves the ability to look ahead in the evolving temporal trajectory of the ISS operations and to juggle pre-planned fixes along these trajectories. A key objective of this paper is to illustrate how anticipation is shared between humans and different forms of technology. Moreover, it illustrates the importance of including considerations of temporality in safety and reliability research.     

Online buying perceptions in Spain: can gender make a difference?

Internet has led to radical changes in commercial relations and especially in consumer buying habits. Considering the peculiar characteristics of Internet shopping, it is difficult to engender consumer online trust and consumer face an adverse selection problem when having to choose the best web site to buy from. This problem may be mitigated by signaling the high-quality and good behavior of the e-vendor or by consumer satisfactory experiences. As gender can make differences in the decision-making processes of individuals, the purpose of this study is to find out if there are gender differences regarding the effect of three specific signals of quality—service quality, warranty, and security and privacy policies– on e-satisfaction and e-trust, and on the relation between satisfaction and trust. The research questions were tested using information gathered from Spanish online buyers and using structural equation modeling. Results suggest that suitable gender-based signaling strategies could conceivably be prepared in accordance with the target population, which holds interesting implications for both the academic and the professional world.     

Skewed distributions in semi-stream joins: How much can caching help?

Semi-stream join algorithms join a fast data stream with a disk-based relation. This is important, for example, in real-time data warehousing where a stream of transactions is joined with master data before loading it into a data warehouse. In many important scenarios, the stream input has a skewed distribution, which makes certain performance optimizations possible.We propose two such optimization techniques: (1) a caching technique for frequently used master data and (2) a technique for selective load shedding of stream tuples. The caching technique is fine-grained, operating on a tuple-level. Furthermore, it is generic in the sense that it can be applied to different semi-stream join algorithms to deal with data skew. We analyze it by combining it with various well-known semi-stream joins, and show that it improves the service rate by more than 40% for typical data with skewed distributions. The load shedding technique sheds the fraction of the stream that is most expensive to join. In contrast to existing approaches, the service rate improves under load shedding. We present experimental data showing significant improvements as compared to related approaches and perform a sensitivity analysis for various internal parameters.     

DEI in the IS discipline: What can we do better?

Recent diversity, equity, and inclusion (DEI) efforts have made some limited progress in addressing underrepresentation and unequal opportunities for minority members in the Information Systems (IS) academic community. The Association for Information Systems (AIS), as the preeminent global professional society for the IS discipline, is tasked with acting on behalf of its members and their colleagues to achieve equity and inclusion for its diverse membership. This editorial has two aims: (1) to share the extent to which positive changes have been made and also the extent to which underrepresentation still pervades the IS academic community, especially at the senior ranks and in positions of power, and (2) to propose a coordinated, strategic focus that our field, our journals and conferences, and our association (AIS) can take to further improve diversity and inclusion for both junior and senior minority colleagues.     

Patterns of kindergarten children’s social interaction with peers in the computer area

This study explored how young children interact with their peers in the computer area of a public kindergarten classroom. Children??s social interaction, as defined in this study, is the action of giving and taking information that results in children??s knowledge construction and cognitive development that can be accomplished through peer-to-peer interactions. This kind of social interaction is referred to as ??Cognitively Effective Social Interaction (CESI)?? in this paper. Patterns of young children??s social interaction with peers in the computer area of this classroom were discussed. Two teachers and 28 children in a full-day kindergarten classroom were observed and interviewed. The patterns of young children??s social interaction that occurred in the computer area were described as parallel play, verbal conflicts, sociable interaction, knowledge construction through positive and negative processes, and non-verbal communication.     

How can we learn leadership? The vision of the Europe-wide University

In the view of many students, business and engineering education in Europe today do not sufficiently take into account complex problems, tendencies of chaos and uncontrollable business behaviour, and the lack of mutual trust in business transactions. Additionally, universities seem to fail in creating leaders, instead focusing on educating future managers. Therefore, the student-run international organisation the European Students of Industrial Engineering and Management (ESTIEM) offers a whole series of educational activities and programmes in parallel to their own university courses. It is based on the concept of experiential learning. Through ESTIEM, we, students of Industrial Engineering Management, learn and practise working in teams with shared and rotating leadership among ourselves. These experiences are to be described in the paper in some more detail, as a model for university education in industrial engineering and management. Furthermore, the following questions will be tackled: What does leadership mean today? How are problems handled by leaders and managers in industry nowadays? How can leadership to solve complex problems be taught in the university? As a consequence, it is suggested to develop out of the ESTIEM programmes, a series of university-equivalent ESTIEM courses. In the long term, the goal might be to realise the vision of a genuine Europe-wide “ESTIEM University” in its own right, similar to normal universities which will help in shaping new leadership generation in Europe.     

How can a complex square root be computed in an optimal way?

We give an optimality analysis for computations of complex square roots in real arithmetic by certain computation tress that use real square root operations. Improving standard elementary geometric constructions Schönhage suggests better methods which will be shown to be unimprobable. The iteration of such a procedure for 2 ^k -th roots is however improvable, and an improved version of it can also be shown to be unimprovable. In particular, repeated usage of an optimal square root procedure does not yield an optimal one for 2 ^k -th roots.To answer this kind of questions about resolution by real radicals we apply methods of real algebra which lead into the theory of real field, ring, and integral ring extensions.     

Quantification of grassland properties: how it can benefit from geoinformatic technologies?

The emergence of advanced geoinformatic techniques raises the feasibility of successfully quantifying grassland properties. Accurate quantification of these parameters faces opportunities and challenges, both of which are reviewed critically in this paper. The principle of quantifying grassland properties is presented first, together with the requirements, followed by a review of the grassland properties (percentage grass cover, grassland biomass and grassland degradation) that have been quantified. Assessment of quantification accuracy has evolved from reliance on the R ² value of regression analysis to comparison against independent samples, with the highest accuracy being 89%. Achievement of higher accuracy is hindered by three obstacles, namely positional uncertainty of in situ samples, differential ground and image sampling intervals, and temporal irreversibility of historical satellite images. It is proposed that the global positioning system (GPS) be used to handle the first challenge, and hyperspatial resolution images to minimize disparity in the sampling intervals. The third challenge should be tackled through radiometric calibration of historic images based on invariant ground targets. With the emergence of hyperspectral imagery (e.g. AVIRIS and CASI), more grassland features (e.g. grassland productivity and carrying capacity) can be quantified in the future in a geographic information system (GIS). It is concluded that advances in the geoinformatic technology will enable more grassland properties to be quantified more accurately.     

Backshapes of seated persons—how close can the interface be designed?

The backshapes of 114 seated persons were measured. The horizontal and vertical positions of various spinal landmarks are given for male and female subjects and for those with lordotic, straight and kyphotic backs.     

Who can receive the pass? A computational model for quantifying availability in soccer

Data Mining and Knowledge Discovery - The paper presents a computational approach to Availability of soccer players. Availability is defined as the probability that a pass reaches the target player...     

Ergonomics in total quality management: how can we sell ergonomics to management?

The objective of this paper is to describe how and why ergonomics should be promoted in total quality management (TQM). Ergonomics and TQM activities are compared. An approach is proposed to apply ergonomics in TQM using ergonomics circles. An eight-step approach is introduced for applying ergonomics using ergonomics circles and a study that employed this approach in Korea is discussed. In applying this approach, all processes were first evaluated by workers. Processes that were identified as problematic were analysed by a company-wide committee to set priorities for improvement. An ergonomics improvement team consisting of safety and health personnel, process engineers and management innovation personnel then worked on the processes using a low-cost approach. It was found that applying ergonomics using ergonomics circles as quality circles in TQM was effective in improving workplaces and resulted in increasing productivity, cost saving and improved safety.     

Multi‐year circumpolar assessment of the area burnt in boreal ecosystems using SPOT‐VEGETATION

The Russian Academy of Sciences' Space Research Institute has developed a new burnt area mapping method and a five‐year database to estimate biomass burning in the Earth's entire boreal region. The mapping method involved SPOT‐VEGETATION time‐series data analysis to detect inter‐annual vegetation changes combined with MODIS hot‐spot data to distinguish fire‐related changes from other types of disturbances. The burnt area database actually covers the boreal biome for the period 2000–2004 with 1 km spatial resolution and 10‐day time frequency, while an automatic data processing chain allows this database to be updated continuously. The accuracy assessment involved comparison with Landsat‐ETM+ derived burnt area estimates for Northern Eurasia and ground data for Canada. This Letter describes the satellite sensor data processing method and the results of the accuracy assessment of the burnt area database and provides burnt area statistics for the boreal region countries.     

Use or Abuse of Improvisation in Organizations?

This paper studies the uses and abuses of improvisation in craft breweries in Brazil and Germany. Using semi‐structured interviews, it shows theory‐based empirical evidence of improvisation and learning in organizations. Given the well‐known use of improvisation in the arts, the paper makes a parallel between the role of improvisation in organizations and in arts' activities in order to evaluate the advantages and disadvantages of improvisation, although this study goes beyond the use of metaphors and carries out a direct analysis of improvisation in organizations. The empirical analysis was conducted with 24 managers, head brewers and employees from craft breweries in Brazil and Germany. Using a multiple case study approach, with interviews, direct observation and storytelling, this research shows evidence of improvisation in breweries. The analysis uncovers and evaluates the uses and abuses of improvisation in organizations.