A value-driven approach to the design of service-oriented information systems—making use of conceptual models

We explain the importance of conceptual models for process design with service-oriented architectures (SOA) and illustrate how these models can be used to evaluate the value of SOA. To do so, a methodology is introduced, which comprises both the configuration and the implementation of processes by services and IT components. The approach presented here, makes it possible to evaluate the monetary and objective potentials of SOA, as well as to enhance SOA implementation by providing guidelines. The requirements analysis from an online-mail order company serves as a case study. The results show that up to now, economic aspects were ascribed too little importance in the SOA discussion.     

How does e-mail use affect perceived control of time?

It is well established in the psychology literature that personality predicts performance to some degree. However, personality neither solely nor directly predicts outcomes. Rather, performance and outcomes unfold through context-specific mediating constructs. This study identified two constructs that mediate the relationship between proactivity and perceived control of time in e-mail use and tested the model with data from 251 knowledge workers. The results show that proactivity predicts the perceived control of time in e-mail use through both e-mail-specific time management behavior and e-mail self-efficacy. Further, greater e-mail self-efficacy leads to improved e-mail-specific time management behavior.     

Linking objective design factors with subjective aesthetics: An experimental study on how structure and color of websites affect the facets of users’ visual aesthetic perception

The present study examines how objective design factors of a website are linked to different facets of subjective aesthetic perception. Five online experiments based upon the screenshots of real-existing websites with a total of N = 194 participants were conducted to isolate and analyze the effects of two objective structural factors (vertical symmetry, visual complexity) and three objective color factors (hue, saturation, brightness) on the different facets of subjective aesthetic perception (simplicity, diversity, colorfulness, craftsmanship) measured with the Visual Aesthetics of Website Inventory (Moshagen & Thielsch, 2010). Although all investigated factors are apparent features in website design, their effects on different facets of subjective aesthetic perception are not yet well understood. Our results show that websites of high symmetry, low complexity, blue hue, medium brightness or medium and high saturation received the highest overall aesthetics ratings. Furthermore, data reveal that structural factors compared to color factors have a manifold and greater impact on the different facets of subjective aesthetic perception than the color factors. Both structural factors have a great impact on simplicity, diversity and craftsmanship whereas the color factors have a great impact especially on colorfulness. Only complexity affects all facets of subjective aesthetic perception. The other objective design factors had effects on specific facets. Our findings shed light on the relationship between objective and subjective factors of aesthetic perception and may help designers to systematically target specific facets of visual aesthetics.     

Work or leisure? Designing a user-centered approach for researching activity “in the wild”

Mobile devices have conquered nearly all parts of the daily life. These devices support their owners in specific situations, both at work and in leisure contexts, and therefore make it increasingly difficult to keep work and private life separated. Examining the practices around the use of mobile technology has become a topic of some interest as issues around “work–life balance” emerge. Although the field of HCI provides different approaches for capturing people’s activities in situ, we will show that an additional value can be obtained from a consideration of the “situated” view of contextuality, one which incorporates concerns of privacy and which identifies the reasons people might have for long-term user participation in this kind of study. Despite the undoubted sophistication of existing platforms, the issue of how to provide for dynamic adjustment to meet emerging research questions over time remains challenging. In this paper, we examine how one might approach the design of an observation environment that includes methods for understanding the way of how users reason about research, based upon the context they find themselves in. We have developed a research framework called “PartS,” which captures in situ information about the individual as well as his/her (work/personal) context and offers functionality for collaborative discussions about the information collected. Based on its evaluation, we outline six lessons that need to be considered when designing a study for capturing the subjective context and related activities from an individual user’s as well as a researcher’s perspective.     

Changing the role of the air traffic controller: how will free flight affect memory for spatial events?

At present, air traffic controllers (ATCOs) exercise strict control over routing authority for aircraft movement in airspace. The onset of a free flight environment, however, may well result in a dramatic change to airspace jurisdictions, with aircraft movements for the large part being governed by aircrew, not ATCOs. The present study examined the impact of such changes on spatial memory for recent and non-recent locations of aircraft represented on a visual display. The experiment contrasted present conditions, in which permission for manoeuvres is granted by ATCOs, with potential free flight conditions, in which aircrew undertake deviations without explicit approval from ATCOs. Results indicated that the ATCO role adopted by participants impacted differently on short-term and long-term spatial representations of aircraft manoeuvres. Although informing participants of impending deviations has beneficial effects on spatial representations in the short term, long-term representations of spatial events are affected deleteriously by the presentation of subsequent information pertaining to other aircraft. This study suggests strongly that recognition of the perceptual and cognitive consequences of changing to a free flight environment is crucial if air safety is not to be jeopardized.     

A functional approach to the stability of non-linear systems by use of the comparison theorem†

The paper presents some stability conditions for non-linear systems based on the application of the comparison theorem. The non-linear integral equation which gives the output of the system is dominated by another non-linear integral equation of simpler structure. The study of the boundedness of this equation is carried out by considering an algebraic equation; the stability conditions for the non-linear system corresponds to the existence of real positive roots of the algebraic equation.     

A teaching–learning based optimization approach for economic design of X-bar control chart

Being simple to use X-bar control chart has been most widely used in industry for monitoring and controlling manufacturing processes. Measurements of a quality characteristic in terms of samples are taken from the production process at regular interval and the sample means are plotted on this chart. Design of a control chart involves the selection of three parameters, namely the sample size (n), the sampling interval (h) and the width of control limits (k). In case of economic design, these three control chart parameters are selected in such a manner that the total cost of controlling the process is the least. The effectiveness of this design depends on the accuracy of determination of these three parameters. In this paper, a new efficient and effective optimization technique named as teaching–learning based optimization (TLBO) has been used for the global minimization of a loss cost function expressed as a function of three variables n, h and k in an economic model of X-bar chart based on unified approach. In this work, the TLBO algorithm has been modified to simplify the tuning of teaching factor. A MATLAB computer program has been developed for this purpose. A numerical example has been solved and the results are found to be better than the earlier published results. Further, the sensitivity analysis using fractional factorial design and analysis of variance have been carried out to identify the critical process and cost parameters affecting the economic design.     

How do construal levels affect the intertemporal choices of Internet addicts?

Although various studies have shown that construal levels affect intertemporal choices, how this specifically occurs in individuals with Internet addiction remains unknown. We aimed to examine how do construal levels affect the intertemporal choices of Internet addicts. This study employed a 2 × 2 experimental design to explore this issue in greater depth, with 55 Internet addicts and 55 healthy controls that were well matched in age and gender. Each participant experienced one of two construal level priming conditions (high versus low) before completing an intertemporal decision-making task. The results of the experiment revealed that construal level had an effect on the intertemporal choices of Internet addicts as well as healthy controls. However, the subjective values of the intertemporal choices of participants with Internet addiction were significantly lower. Additionally, the subjective values of intertemporal choices were significantly higher among participants who had been primed to have a high construal (i.e., more abstract) mindset as opposed to a low construal (i.e., more concrete) one. This result further affirmed the influence of construal level on intertemporal choice, regardless of whether individuals were addicted to the Internet. Although Internet addicts discounted delayed gains more steeply than did normal Internet users, both exhibited shortsightedness in the low construal level priming condition. These results suggest that Internet addicts as well as normal users are more long-sighted in high construal level priming condition. Implications of the current findings for long-term benefit planning or goal setting and the development of effective interventions are discussed.     

Evidential reasoning-based Fuzzy AHP approach for the evaluation of design alternatives’ environmental performances

With the growing general awareness of the need to protect the environment as well as the increasingly stringent regulatory requirements imposed by various national and cross-national bodies, manufacturers have to minimise the environmental impacts of their products. Environmental considerations have therefore become a new key criterion for evaluating design alternatives during the product development stage. To facilitate non-Life Cycle Assessment (LCA) experts, such as most product designers, in evaluating the design alternatives in terms of environmental friendliness, this paper introduces a decision-making mechanism that combines the multiple criteria decision making (MCDM) approaches with LCA methodology. This evidential reasoning-based approach is a fast-track and objective tool which ranks the available design alternatives according to their potential environmental impacts. The environmental impacts of design alternatives assessed by the LCA are used for the weight elicitation processes of the proposed approach. A case application is conducted to illustrate the use of the proposed method to evaluate the environmental performances of design alternatives.     

How close are we to solving the problem of automated visual surveillance?

The problem of automated visual surveillance has spawned a lively research area, with 2005 seeing three conferences or workshops and special issues of two major journals devoted to the topic. These alone are responsible for somewhere in the region of 240 papers and posters on automated visual surveillance before we begin to count those presented in more general fora. Many of these systems and algorithms perform one small sub-part of the surveillance task, such as motion detection. But even with low level image processing tasks it is often difficult to compare systems on the basis of published results alone. This review paper aims to answer the difficult question “How close are we to developing surveillance related systems which are really useful?” The first section of this paper considers the question of surveillance in the real world: installations, systems and practises. The main body of the paper then considers existing computer vision techniques with an emphasis on higher level processes such as behaviour modelling and event detection. We conclude with a review of the evaluative mechanisms that have grown from within the computer vision community in an attempt to provide some form of robust evaluation and cross-system comparability.     

How does the smartphone usage of college students affect academic performance?

The present study aims to investigate the effects of smartphone use by college students on their perceived academic performance. Using five hypotheses derived from the literature related to smartphone use, the initial model was set up for path analysis to reveal the relationships among variables regarding college students' smartphone use in the academic setting. Moreover, multiple group analyses were additionally conducted to verify whether students exhibited different relationships in the hypothesized model depending on their majors. The results from path analyses showed that all path coefficients were positive and statistically significant, which indicated that all five hypothesized paths were supported. Above all, the results from multiple group analysis showed that one path (from Behavioural Intention to Use Smartphone to Academic Performance) differed significantly across groups. The findings from the current study provide educational policymakers and educators with information on how smartphone utilization in learning activities influences students' academic performance.     

How valuable is medical social media data? Content analysis of the medical web

It is still an open question where to search for complying a specific information need due to the large amount and diversity of information available. In this paper, a content analysis of health-related information provided in the Web is performed to get an overview on the medical content available. In particular, the content of medical Question & Answer Portals, medical weblogs, medical reviews and Wikis is compared. For this purpose, medical concepts are extracted from the text material with existing extraction technology. Based on these concepts, the content of the different knowledge resources is compared. Since medical weblogs describe experiences as well as information, it is of large interest to be able to distinguish between informative and affective posts. For this reason, a method to classify blogs based on their information content is presented, which exploits high-level features describing the medical and affective content of blog posts. The results show that there are substantial differences in the content of various health-related Web resources. Weblogs and answer portals mainly deal with diseases and medications. The Wiki and the encyclopedia provide more information on anatomy and procedures. While patients and nurses describe personal aspects of their life, doctors aim to present health-related information in their blog posts. The knowledge on content differences and information content can be exploited by search engines to improve ranking, search and to direct users to appropriate knowledge sources.     

A non-linear programming approach to the computer-aided design of regulators using a linear-quadratic formulation†

A design technique is proposed for linear regulators in which a feedback controller of fixed structure is chosen to minimize an integral quadratic objective function subject to the satisfaction of integral quadratic constraint functions. Application of a non-linear programming algorithm to this mathematically tractable formulation results in an efficient and useful computer-aided design tool. Particular attention is paid to computational efficiency and various recommendations are made. Two design examples illustrate the flexibility of the approach and highlight the special insight afforded to the designer.     

A GRASP × ELS approach for the job-shop with a web service paradigm packaging

The Job-Shop Scheduling Problem (JSSP) is well known for its complexity as an NP-hard disjunctive scheduling problem. The problem addressed in this paper is JSSPs with an objective of minimizing makespan while satisfying a number of hard constraints. An efficient GRASP × ELS approach is introduced for solving this problem. The efficiency is evaluated using the widely known 40 Laurence’s instances which encompass medium and large scale instances. The computational results prove that the proposed method competes with the best published methods in both quality of results and computational time. Recently, Web services have generated great interest in researchers. Such application architecture is based on the client–server model using existing Internet protocols and open standards. It provides new approaches to optimization methods. The proposed GRASP × ELS is packaged into a Web Service (WS), i.e., it offers for the research community an open access to our optimization approach. Moreover, the proposed web service can be even included in research future works with a very small programming effort.To favor utilization of the web service and to prove the facility in which the service could be used, we provide an example in Java proving that it is possible to obtain in less than 10 min a client application using the different methods exposed by this web service. Such usage extends to classical library inclusion in program with the difference that a method is called in the client side and represents an execution on the server.The Web Service paradigm is a new approach in spreading algorithms and therefore this paper stands at the crossroads of optimization research community and the web service community expectations. The GRASP × ELS provided in the web service, is a state of the art method which competes with previously published ones and which has the advantage of being available for free, in any languages, everywhere contributing in spreading operational research contribution.     

A spatial–spectral kernel-based approach for the classification of remote-sensing images

Classification of remotely sensed images with very high spatial resolution is investigated. The proposed method deals with the joint use of the spatial and the spectral information provided by the remote-sensing images. A definition of an adaptive neighborhood system is considered. Based on morphological area filtering, the spatial information associated with each pixel is modeled as the set of connected pixels with an identical gray value (flat zone) to which the pixel belongs: The pixel's neighborhood is characterized by the vector median value of the corresponding flat zone. The spectral information is the original pixel's value, be it a scalar or a vector value. Using kernel methods, the spatial and spectral information are jointly used for the classification through a support vector machine formulation. Experiments on hyperspectral and panchromatic images are presented and show a significant increase in classification accuracies for peri-urban area: For instance, with the first data set, the overall accuracy is increased from 80% with a conventional support vectors machines classifier to 86% with the proposed approach. Comparisons with other contextual methods show that the method is competitive.     

Modular approach to the design and analysis of password-based security protocols

In this paper, a general framework for designing and analyzing password-based security protocols is presented. First we introduce the concept of "weak computational indistinguishability" based on current progress of password-based security protocols. Then, we focus on cryptographic foundations for password-based security protocols, i.e., the theory of "weak pseudorandomness". Furthermore, based on the theory of weak pseudorandomness, we present a modular approach to design and analysis of password-based security protocols. Finally, applying the modular approach, we design two kinds of password-based security protocols, i.e., password-based session key distribution (PSKD) protocol and protected password change (PPC) protocol. In addition to having forward secrecy and improved efficiency, new protocols are proved secure.     

Why you will use the deep X-ray LIG(A) technology to produce MEMS?

Geometrical and dimensional tolerances, obtainable precisions, accuracy, surface quality and roughness need to be controlled in order to realise effective processes and to achieve a real improvement in micromanufacturing technologies. For the fabrication of highly precise mm parts, different processes can be chosen. The LIGA technique, a German acronym consisting of the letters LI (Röntgen Lithographie meaning X-ray lithography), G (Galvanik meaning electroforming) and A (Abformung meaning molding) developed at the Research Center Karlsruhe, offers the possibility to manufacture microstructures with a number of unique features. With these properties, LIGA is on the leading edge of microfabrication. This is a well known issue to most participants in the micro sector. However, most actors consider LIGA to be very expensive, to take much time from design up to realization, and to impose a number of quality problems. In this paper, we try to modify the perception of the LIGA process by addressing some quality properties of the process by taking two different examples and we address the throughput and cost situation by establishing a mass fabrication line for direct LIGA products at ANKA.     

Application of the QFD as a design approach to ensure comfort in using hand tools: Can the design team complete the House of Quality appropriately?

Quality Function Deployment is proposed as an effective design method to integrate ergonomics needs and comfort into hand tool design because it explicitly addresses the translation of customer needs into engineering characteristics. A crucial step during QFD concerns the linking of engineering characteristics to customer needs in the House of Quality by the design team. It is generally assumed (looking at all the QFD success stories) that design teams can accurately predict the correlations between customer needs and engineering characteristics (also referred to as “Whats”/“Hows” correlations). This paper explicitly tests this assumption by comparing the “Whats”/“Hows” correlations estimated by a design team with those observed in a systematic user evaluation study, which has not been done before. Testing the assumption is important, because inaccurate estimates may lead to ergonomically ineffective (re)design of hand tools and a waste of company resources. Results revealed that the design team's correlation estimates were not as accurate as is generally assumed. Twenty-five percent of the estimates differed significantly with those observed in the user evaluation study. Thus, QFD is a useful method to assist design teams in designing ergonomically more comfortable hand tools, but only on the condition that the correlations between customer needs and engineering characteristics are validated, preferably by means of a systematic user evaluation study.     

A stress–based approach to the optimal design of structures with unilateral behavior of material or supports

The paper presents a stress-based approach that copes with the optimal design of truss-like elastic structures in case of unilateral behavior of material or ground supports. The conventional volume-constrained minimization of compliance is coupled with a set of local stress constraints that are enforced, all over the domain or along prescribed boundaries, to control the arising of members with tension-only or compression-only strength. A Drucker–Prager failure criterion is formulated to provide a smooth approximation of the no-tension or no-compression conditions governing the stress field. A selection strategy is implemented to handle efficiently the multi-constrained formulation that is solved through mathematical programming. Benchmark examples are investigated to discuss the features of the achieved optimal designs, as compared with problems involving material and ground supports with equal behavior in tension and compression. Numerical simulations show that a limited set of constraints is needed in the first iterations to steer the solution of the energy-driven optimization towards designs accounting for the prescribed assumption of unilateral strength.     

Who votes for what? A visual query language for opinion data

Surveys and opinion polls are extremely popular in the media, especially in the months preceding a general election. However, the available tools for analyzing poll results often require specialized training. Hence, data analysis remains out of reach for many casual computer users. Moreover, the visualizations used to communicate the results of surveys are typically limited to traditional statistical graphics like bar graphs and pie charts, both of which are fundamentally noninteractive. We present a simple interactive visualization that allows users to construct queries on large tabular data sets, and view the results in real time. The results of two separate user studies suggest that our interface lowers the learning curve for naive users, while still providing enough analytical power to discover interesting correlations in the data.