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991.
Enterprise activities are governed by regulations and laws that are multiple, heterogeneous and not always easy to understand. The arising and/or the modification of these regulations and laws can cause a significant impact in the business context, especially in terms of enterprise information systems adaptation. Currently, there are many methodological and technological tools that facilitate the application of regulations and procedures, but they are not integrated enough to ensure a complete problem management. Therefore, they are not sufficient to support organizations and companies in the management of their business processes. In this paper we propose a methodological and technological solution, able to model, manage, execute and monitor business processes of complex domains. The system allows both the design of an information system and its prototyping as a web application, by the extension of an appropriately selected Business Process Management suite. During both the design and the usage phases of the prototyped information system, it is possible to interface with a knowledge base that contains information about regulations and aspects that characterize the enterprise (organizational chart, tasks, etc.).  相似文献   
992.
E-procurement and supplier-relationship management systems have helped to substantially advance process execution in supply management. However, current supply network systems still face challenges of high data integration efforts, as well as the decoupling of structured data and processes from the growing amount of digitalized unstructured interactions of supply management professionals. Inspired by the room for improvement posed by this challenges, our research proposes a design for a supply network artifact in supplier qualification that addresses these problems by enabling holistic integration of data, processes, and people. The artifact is developed following an action design research approach. Building on a set of meta-requirements derived from literature and practice explorations, we conceptualize two design principles and derive corresponding design decisions that have been implemented in an software artifact. Finally, we formulate testable hypotheses and evaluate the artifact and its design in the context of supplier qualification. Our results show that the proposed design reduces mental effort of supply management professionals and significantly increases efficiency when performing typical supply network tasks such as supplier qualification.  相似文献   
993.
Gaze-controlled interfaces have become a viable alternative to hand-input-based displays and present a particular value to the field of assistive technologies, allowing people with motor disabilities to partake in activities that otherwise would have been inaccessible to them. The present paper gives an overview of the key problems associated with the user experience in gaze-controlled human–computer interfaces and introduces two areas of psychological research that could contribute to the development of gaze-controlled interfaces that give a more intuitive sense of control and are less likely to interfere with ongoing cognitive processes. Such interfaces are referred to as cognitively grounded. The two areas of psychological research that lead to the design of cognitively grounded gaze-controlled interfaces are the sense of agency and the cognitive embodiment. This overview builds on findings within these areas and outlines research questions essential to the design of cognitively grounded gaze-controlled interfaces.  相似文献   
994.
This paper examines the success of an e-learning system in a company from the perspective of employees by using a multimethod approach. For this purpose Moodle learning management system was used. The success of e-learning as an information system was evaluated using four constructs of the updated DeLone and McLean IS success model—system quality, use, user satisfaction and net benefits, and adding one more construct—user performance. In this research a combination of observation and survey as two different research methods was used, which allowed the new measure to be incorporated into the model. Empirical assessment was carried out by exploratory factor analysis, confirmatory factor analysis and structural equation modeling. The research model was found to be valid and reliable. The results provide an expanded understanding of the constructs that measure the success of an e-learning system, helping to more deeply understand the key success dimensions and their interrelationships. The implications of our work were discussed. The DeLone and McLean IS success model applied equally well. However, the use of observation as a method of data collection revealed the weaknesses of the original model.  相似文献   
995.
This paper presents an approach to modular contract-based verification of discrete-time multi-rate Simulink models. The verification approach uses a translation of Simulink models to sequential programs that can then be verified using traditional software verification techniques. Automatic generation of the proof obligations needed for verification of correctness with respect to contracts, and automatic proofs are also discussed. Furthermore, the paper provides detailed discussions about the correctness of each step in the verification process. The verification approach is demonstrated on a case study involving control software for prevention of pressure peaks in hydraulics systems.  相似文献   
996.
997.
Technology is often seen as seamless, or making (life/work) boundaries go away. Ubicomp designs for that and for seamlessness in general. However, there may be better ways of understanding boundaries, as to design technologies in the space of changing work/life boundaries, which is the topic of this special issue. This paper makes a theoretical argument to insist that boundaries are not fixed, neither can or should they be made away with technologically, through seamless technologies. Based on this argument, it discusses various presumed technology-mediated boundaries of work and home, life, etc., as they can be found in the Ubicomp, CSCW and HCI literature: The ways in which work and work technologies are stereotypically connected to effectiveness and hard labor, and non-work technologies to fun and enjoyment; the ways in which technologies move back and forth between mediating work activity and non-work; the role of place and time boundaries in relation to the ability to work any time, anywhere and the metaphors used to address these boundaries; and the perceived boundaries of private versus public, and the new boundaries created by technologies in and across our lives and work. Using an empirical case, the paper offers an alternative use of boundaries as resources to be activated and used in design. It suggests that we need to more carefully design technologies that provide seamfulness on these specific and dynamic boundaries.  相似文献   
998.
Mobile devices offer a common platform for both leisure and work-related tasks, but this has resulted in a blurred boundary between home and work. In this paper, we explore the security implications of this blurred boundary, both for the worker and the employer. Mobile workers may not always make optimal security-related choices when “on the go” and more impulsive individuals may be particularly affected as they are considered more vulnerable to distraction. In this study, we used a task scenario, in which 104 users were asked to choose a wireless network when responding to work demands while out of the office. Eye-tracking data was obtained from a subsample of 40 of these participants in order to explore the effects of impulsivity on attention. Our results suggest that impulsive people are more frequent users of public devices and networks in their day-to-day interactions and are more likely to access their social networks on a regular basis. However, they are also likely to make risky decisions when working on-the-go, processing fewer features before making those decisions. These results suggest that those with high impulsivity may make more use of the mobile Internet options for both work and private purposes, but they also show attentional behavior patterns that suggest they make less considered security-sensitive decisions. The findings are discussed in terms of designs that might support enhanced deliberation, both in the moment and also in relation to longer term behaviors that would contribute to a better work–life balance.  相似文献   
999.
Internet Data Center (IDC) is one of important emerging cyber-physical systems. To guarantee the quality of service for their worldwide users, large Internet service providers usually operate multiple geographically distributed IDCs. The enormous power consumption of these data centers may lead to both huge electricity bills and considerable carbon emissions. To mitigate these problems, on-site renewable energy plants are emerging in recent years. Since the renewable energy is intermittent, greening geographical load balancing (GGLB for short) has been proposed to reduce both the electricity bills and carbon emissions by following the renewables. However, GGLB is not able to well deal with the wildly fluctuating wind power when applied into IDCs with on-site wind energy plants. It may either fail to minimize the total electricity bills or incur the costly frequent on–off switching of servers. In order to minimize the total electricity bills of geographically distributed IDCs with on-site wind energy plants, we formulate the total electricity bills minimization problem and propose a novel two-time-scale load balancing framework TLB to solve it. First, TLB models the runtime cooling efficiency for each IDC. Then it predicts the future fine-grained (e.g., 10-min) on-site wind power output at the beginning of each scheduling period (e.g., an hour). After that, TLB transforms the primal optimization problem into a typical mixed-integer linear programming problem and solves it to finally obtain the optimal scheduling policy including the open server number as well as the request routing policy. It is worth noting that the open server number of each IDC will remain the same during each scheduling period. As an application instance of TLB, we also design a two-time-scale load balancing algorithm TLB-ARMA for our experimental scenario. Evaluation results based on real-life traces show that TLB-ARMA is able to reduce the total electricity bills by as much as 12.58 % compared with the hourly executed GGLB without incurring the costly repeated on–off switching of servers.  相似文献   
1000.
Predicting the centrality of nodes is a significant problem for different applications in Opportunistic Mobile Social Networks (OMSNs). However, when calculating such metrics, current studies focused on analyzing static networks that do not change over time or using aggregated contact information over a period of time. Furthermore, the centrality measured in the past is not verified whether it is useful as a predictor for the future. In this paper, in order to capture the dynamic behavior of people, we focus on predicting nodes’ future centrality (importance) from the temporal perspective using real mobility traces in OMSNs. Three important centrality metrics, namely betweenness, closeness, and degree centrality, are considered. Through real trace-driven simulations, we find that nodes’ future centrality is highly predictable due to natural social behavior of people. Then, based on the observations in the simulation, we design several reasonable prediction methods to predict nodes’ future temporal centrality. Finally, extensive real trace-driven simulations are conducted to evaluate the performance of our proposed methods. The results show that the Recent Weighted Average Method performs best in the MIT Reality trace, and the recent Uniform Average Method performs best in the Infocom 06 trace. Furthermore, we also evaluate the impact of parameters m and w on the performance of the proposed methods and find proper values of different parameters for each proposed method at the same time.  相似文献   
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