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991.
Currently, open source software (OSS) products have started to become popular in the market as an alternative to traditional proprietary or closed source software. Governments and organizations are beginning to adopt OSS on a large scale and several governmental initiatives have encouraged the use of OSS in the private sector. One major issue for the government and private sector is the selection of appropriate OSS. This paper uses new internal quality characteristics for selecting OSS that can be added to the dimensions of DeLone and McLean information systems’ model. Through this study, the quality characteristics are organized in a two level hierarchy, which list characteristics and sub-characteristics that are interconnected with three main dimensions: system quality, information quality and service quality. These characteristic dimensions are tailored to the criteria having been built from literature study and standard for software quality and guidelines. This paper presents case study results of applying the proposed quality characteristic on eight different open source software that are divided between open source network tools and learning management systems. 相似文献
992.
Marinho P. Barcellos Rodolfo S. AntunesHisham H. Muhammad Ruthiano S. Munaretti 《Journal of Network and Computer Applications》2012,35(1):328-339
Simulation has been of paramount importance to the development of novel Internet protocols. Such an approach typically focuses on one of three domains: wireless and other link-layer technologies, routing protocols, and transport-layer mechanisms and protocols. Existing techniques can tackle well simulation at layers 2, 3 and 4 of the TCP/IP architecture, but are not flexible enough to appropriately deal with application-layer protocols. These require simulators that support the modeling of networks and components with different levels of abstraction. Simmcast is an object-oriented framework that focuses on the necessary flexibility for application-layer protocol research. A simulation can be developed by the simple extension of building blocks that closely resemble components of a real network such as hosts, links and routers. The internal complexity of these components, however, is hidden from the user, so he/she can focus on the implementation of the desired protocol characteristics. This paper describes the flexible simulation architecture proposed and instantiated through Simmcast, and draws lessons from our experience in designing, implementing and deploying it. We also present framework instances used to evaluate application-layer protocols, exemplifying how different kinds of simulations can be developed with Simmcast. 相似文献
993.
This paper presents a methodology for the testing of intelligent electronic devices (IEDs) in IEC 61850-based substation automation systems (SAS), without any service interruption to the end users, during the testing process. IEC 61850-based SAS provides opportunities for a new level of substation operation, enhancing operating efficiency, and protection reliability based on Ethernet-based communication networks. Due to these changes to the conventional substations, importance and dependency on IEDs is increasing rapidly. Frequency of faults occurring in the power systems is random in nature and is unpredictable. It is necessary to test and maintain the IEDs to ensure their proper operation at crucial times. This paper presents a novel methodology for testing the IEDs, without compromising the service reliability during the testing process. The proposed methodology exploits the inherit characteristics of IEC 61850 standard i.e. Network - based communication, interchangeability between multivendor IEDs, and engineering based on substation configuration language (SCL) files. The feasibility and robustness of the proposed method has been verified by performing several performance verification tests with different performance metrics. 相似文献
994.
《Ergonomics》2012,55(13):887-909
The aim of the study was to establish insight into work exposures that cause shoulder and neck pain among occupational groups that have low biomechanical exposure and experience work stress from client/customer contact, among other exposures. Four occupational groups were studied, in health care (n = 20), retail (n = 22), banking (n = 26), and university secretaries (n = 26), a total of 94 volunteers. Thirty-nine were classified as pain-afflicted in the shoulder and neck, while 55 were pain-free. The subjects' perceptions of biomechanical and psychosocial exposures were established by use of quantitative questionnaires and by explorative interviews with open-ended questions, covering the same themes. Heart rate and trapezius EMG were recorded over a full workday and the following leisure period. Trapezius median and static activity during work were 3.3% and 0.3% EMGmax, only marginally higher than trapezius activity in the leisure period (2.7% and 0.2% EMGmax). The quantitative questionnaire did not identify any variable that correlated with shoulder and neck pain except perceived general tension. The interviews established that the interaction with clients or customers was an important source of work stress. Such stress appeared to be a complex entity not easily characterized by established psychosocial questionnaires. The physiological variables were at most weakly elevated in periods with high stress as compared to periods with low stress. The authors caution against relying on standardized quantitative questionnaires and/or physiological recordings to characterize work stress in occupations with emotional stress through client/customer service work. 相似文献
995.
996.
997.
《Ergonomics》2012,55(4):638-646
A model was developed to determine the inner boundary of the normal horizontal working area based on the concept that the elbow and forearm-hand should move on the table surface while describing the area. The proposed model was applied to determine the normal horizontal working areas for the 5th percentile female and 95th percentile male. It was shown that the conventional models that had disregarded the concept of the inner boundary overestimated the area on the average by 26%. The proposed model is more realistic and accurate than the conventional models. 相似文献
998.
Now days, the businesses are going online and e-Commerce industry is on its boom. In this changing era of development, services are to be Robust, Agile, Accessible and Available to its clients. For secured and guaranteed delivery of services, every big organization is shifting their service delivery model to Enterprise Service Bus (ESB). It promises to set up a strong guideline to build System Oriented Architecture (SOA) system, which leverages multiple services from different application domains. This paper presents an analytical survey of ESB on different parameters influencing the performance of SOA in the present changing scenario and service patterns. 相似文献
999.
《Expert systems with applications》2014,41(8):3761-3768
This paper proposes a data envelopment analysis (DEA) approach to measurement and benchmarking of service quality. Dealing with measurement of overall service quality of multiple units with SERVPERF as multiple-criteria decision-making (MCDM), the proposed approach utilizes DEA, in particular, the pure output model without inputs. The five dimensions of SERVPERF are considered as outputs of the DEA model. A case study of auto repair services is provided for the purpose of illustration. The current practice of benchmarking of service quality with SERVQUAL/SERVPERF is limited in that there is little guidance to whom to benchmark and to what degree service quality should be improved. This study contributes to the field of service quality benchmarking by overcoming the above limitations, taking advantage of DEA’s capability to handle MCDM problems and provide benchmarking guidelines. 相似文献
1000.
In a large course, grading assignments is a time-consuming process requiring considerable resources. Online homework software systems are therefore increasingly being utilized. In this article, we will detail our experiences implementing online homework assignments in our course CH E 243: Engineering Thermodynamics; a large, multi-section course with more than 600 students/year in 4 sections. In Year 1 we employed commercial software, and in Year 2 we developed our own online assignments. In both years, assignments had both online and written components. After each year we conducted a survey of the students to gage their perception regarding the implementation and benefits of the online and written assignments, and the contribution of these tools to the students’ ability to master the material. We found that most students were satisfied with the online system, and recommended using it again the following year. Students generally perceived written assignments to be more helpful in achieving mastery of the course material than the online ones. Students perceived our in-house developed system much more positively than the commercial software (as did we). Overall, we perceived that the class performance was better when our own online assignments were used, and the number of students who failed the course was reduced. 相似文献