• Journal of Construction Engineering and Project Management
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• v.10 no.1
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• pp.16-32
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• 2020

Cost and time control of projects is important in preventing project failure. However, achieving effective cost and time control in practice is often challenging. The challenges of project cost and time control in practice are investigated by carrying out a questionnaire survey on the top 150 construction contractors in the UK followed by in-depth semi-structured interviews of practitioners from 15 construction companies in the country. Quantitative analysis reveals that design change is the most important factor inhibiting the ability of UK contractors from effectively controlling both the cost and time of construction projects. Four of the top five factors inhibiting effective cost control are also the top factors inhibiting effective time control albeit in a different order. These top factors-design changes, inaccurate evaluation of project time/duration, risk and uncertainty, non-performance of subcontractors and nominated suppliers were also found to be endogenous factors to the project. Additionally, qualitative analysis of the interviews reveals 16 key challenges to prevent for effective project cost and time control in practice. These are classified into four categorised based on where they stem from as follows; from the organisation (1. Lack of integration of cost and time during project control, 2. lack of management buy-in, 3. complicated project control systems and processes, 4. lack of a project control training regime); from the construction management/project management approach (5. Lapses in integration of interfaces, 6. project control not being implemented from the early stages of a project, 7. inefficient utilisation and control of labour, 8. limited time devoted to planning how a project will be controlled at the outset); from the client; (9. Excessive authorisation gates, 10. use of adversarial and non-collaborative forms of contracts, 11. communication problems within client set-up, 12. obstructive client representatives) and; from the project team (13. Lack of detailed/complete design, 14. lack of trust among the project partners, 15. limited time devoted to project control on site, 16. non-factual reporting). The study posits that knowledge of these project control inhibiting factors and challenges is the first step at ensuring they are avoided and enable the implementation of a more effective project cost and time control process in practice.

• Journal of Communications and Networks
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• v.6 no.2
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• pp.133-146
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• 2004

Recently, many active queue management (AQM) algorithms have been proposed to address the performance degradation. of end-to-end congestion control under tail-drop (TD) queue management at Internet routers. However, these AQM algorithms show performance improvement only for limited network environments, and are insensitive to dynamically changing network situations. In this paper, we propose an adaptive queue management algorithm, called PID-controller, that uses proportional-integral-derivative (PID) feedback control to remedy these weak-Dalles of existing AQM proposals. The PID-controller is able to detect and control congestion adaptively and proactively to dynamically changing network environments using incipient as well as current congestion indications. A simulation study over a wide range of IP traffic conditions shows that PID-controller outperforms other AQM algorithms such as Random Early Detection (RED) [3] and Proportional-Integral (PI) controller [9] in terms of queue length dynamics, packet loss rates, and link utilization.

• The Journal of Information Systems
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• v.14 no.3
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• pp.1-8
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• 2005

This paper formally defines a role-driven security and access control model of a business process in order eventually to provide a theoretical basis for realizing the secured business process management systems. That is, we propose a graphical representation and formal description of the mechanism that generates a set of role-driven security and access control models from a business process modeled by the information control net(ICN) modeling methodology that is a typical business process modeling approach for defining and specifying business processes. Based upon the mechanism, we are able to design and accomplish a secured business process management system that provides an unified resource access control mechanism of the business process management engine domain's and the application domain's. Finally, we strongly believe that the secured access control policies from the role-driven security and access control model can be easily transformed into the RBAC(Role-based Access Control) model that is a standardized security technology for computer and communications systems of commercial and civilian government organizations.

• Journal of Korean Society for Quality Management
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• v.40 no.3
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• pp.337-346
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• 2012

Purpose: A Control chart is one of the important statistical process control tools that can improve processes by reducing variability and defects. Methods: In the present study, we propose the local $T^2$ multivariate control chart that can efficiently detect abnormal observations by considering the local pattern of the in-control observations. Results: A simulation study has been conducted to examine the property of the proposed control chart and compare it with existing multivariate control charts. Conclusion: The results demonstrate the usefulness and effectiveness of the proposed control chart.

• Journal of Korean Society for Quality Management
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• v.33 no.1
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• pp.1-10
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• 2005

This paper develops a new VSI $\={X}-CRL$ synthetic control chart that considers convenience of use in the field, and perception of change of process applying VSI techniques to synthetic control chart, simultaneously. We found the optimal sampling interval and various control limit factor of the suggested chart using markov chain. Comparison and analysis is carried out between synthetic VSI $\={X}-CRL$ chart and other chart in the statistical aspect; $\={X}$ control chart, VSI $\={X}$ chart, another synthetic chart. In case that the process follows normal distribution, the proposed VSI $\={X}-CRL$ synthetic control chart in detecting process mean shift showed the best performance in aspect of statistical performance, regardless of control limit L of CRL/S control chart.

• Journal of Fashion Business
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• v.16 no.4
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• pp.123-136
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• 2012

The purpose of this study was to analyze body image of women and investigate the relationships of apparel management behavior and weight(figure) control behavior. To achieve the purposes, a questionnaire was conducted to 329 females from October 5 to October 25, 2011. The final data were analyzed with spss 17.0 program. The results were as follows. First, It was found that body image were classified 4 factors of care for appearance, concern about weight, effort of appearance improvement. and appearance attractiveness. Second, there were significant differences of body image by demographic characteristics. Third, there were significant differences of BMI, apparel management behavior and weight(figure) control behavior by demographic characteristics. Forth, there were significant differences of body image, apparel management behavior and weight(figure) control behavior by BMI. Fifth, there were partial significant relations of body image, BMI, appearance management behavior and weight(figure) control behavior. Thus, it was found that body image is related to appearance management behavior and weight(figure) control behavior.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.2
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• pp.261-274
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• 2014

The purpose of this study was to examine the effects of food safety management support in the Center for Children's Foodservice Management (CCFSM) on foodservice facilities for children in Busan area. We assessed the status of hygiene and safety practices of institutional and non-institutional foodservice on a quarterly basis by using an inspection checklist for food hygiene and safety developed by dieticians from February to December in 2013. The subjects were 103 children's foodservices, including 37 institutional and 66 non-institutional foodservices. Inspection checklist consisted of nine categories with 39 checklists; general characteristics, personal hygiene, ingredient control, menu planning, cooking processing control, serving management, washing, disinfection and storage control, and environment and safety management. The average score of each field (pre-supporting/post-supporting) in institutional foodservice was 0.56/0.92 for personal hygiene, 0.55/0.87 for ingredient control, 0.76/0.97 for menu planning, 0.53/0.89 for processing control, 0.27/0.67 for serving management, 0.47/0.91 for washing, disinfection and storage control, and 0.61/0.91 for environment management and 0.64/0.94 for safety management. In non-institutional foodservice, the average score of each field (pre-supporting/post-supporting) was 0.49/0.80 for personal hygiene, 0.52/0.75 for ingredient control, 0.78/0.97 for menu planning, 0.42/0.76 for processing control, 0.32/0.61 for serving management, 0.57/0.88 for washing, disinfection and storage control, and 0.46/0.82 for environment management and 0.73/0.88 for safety management. The average scores of all categories (pre-supporting/post-supporting) were 0.57/0.91 in institutional foodservice and 0.53/0.82 in non-institutional foodservice. The effects of management support in CCFSM on institutional foodservice were higher than those of non-institutional foodservice. Based on these results, we found that management support in CCFSM on foodservice facilities for children had a significantly positive effect on status of hygiene and safety practice regardless of foodservice facility size.

• Journal of the Korea Institute of Building Construction
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• v.8 no.5
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• pp.109-117
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• 2008

Recently, there has been constituted the government regulations and the normative methods to control the safety management activities in construction fields, but almost of these regulations are ineffective, because of some characteristics safety management have. The needs of the times make government regulations and the normative methods change to autonomic management methods. In this context, it is significant certainly to improve the standard of safety management that is used as a tool to protect the workers from the accidents or industrial disasters in the construction field. In this research, it will be showed that the outside regulations and safety management systems of the head office have their limits to reflect the safety managements of field participants. Then, it will be presented the improved model of self-control safety management activities which is essential for success safety management.

• Physical Therapy Korea
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• v.5 no.2
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• pp.47-64
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• 1998

The purposes of this research were to understand the realities of health management and to analyze the subjective, functional, psychological, and social health effects of the application of an exercise and education program to manage health on an elderly population residing in an agricultural community. The specific purposes of this research were: 1. to determine the subjective, functional, psychological health conditions, and performance level of instrumental activities of daily living of both the experimental and control groups before introducing a health management program, and then 2. to compare these with both the experimental and control groups' subjective, functional, psychological health condition and performance level of instrumental activities of daily living after applying the health management program. The health management program was introduced to the experimental group (50 people) but not to the control group (50 people). The health management program was composed of a health exercise program and a health education program. A comparative study of subjective health conditions was done to examine the effect of the health management program and the characteristics of health related variables before and after the program application. The results were as follows: 1. When the experimental group, which had received the 8-week health management exercise and education program, was compared with the control group, which had not, the experimental group's subjective health condition scored higher than that of the control group (p

• Journal of Korean Institute of Industrial Engineers
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• v.40 no.1
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• pp.43-51
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• 2014

Statistical process control (SPC) is an important technique for monitoring and managing the manufacturing process. In spite of its easiness and effectiveness, some problematic sides of application exist such that the SPC techniques are hardly reflect the changes of the process conditions. Especially, update of control limits at the right time plays an important role in acquiring a reasonable performance of control charts. Therefore, we propose the control chart performance evaluation index (CPEI) based on count data model to monitor and manage the performance of control charts. The CPEI could indicate the degree of control chart performance and be helpful to detect the proper update cycle of control limits in real time. Experiments using real manufacturing data show that the proper update intervals are made by proposed method.