• Journal of KIISE:Computer Systems and Theory
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• v.36 no.3
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• pp.140-148
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• 2009

Recent advances in communication and multimedia technologies make it possible to provide video-on-demand(VOD) services and people can access video servers over the Internet at any time using their electronic devices, such as PDA, mobile phone and digital TV. Each device has different processing capabilities, energy budgets, display sizes and network connectivities. To support such diverse devices, multiple versions of videos are needed to meet users' requests. In general cases, VOD servers cannot store all the versions of videos due to the storage limitation. When a device requests a stored version, the server can send the appropriate version immediately, but when the requested version is not stored, the server first converts some stored version to the requested version, and then sends it to the client. We call this conversion process transcoding. If transcoding occurs frequently in a VOD server, the CPU resource of the server becomes insufficient to response to clients. Thus, to admit as many requests as possible, we need to maximize the CPU availability. In this paper, we propose a new algorithm to select versions from those stored on disk using a branch and bound technique to maximize the CPU availability. We also explore the impact of these storage management policies on streaming to heterogeneous users.

• Educational Technology International
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• v.8 no.1
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• pp.17-39
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• 2007

The purpose of this study was to identify the relationships among organizational commitment, job satisfaction, and learning organization culture. This study was conducted in five sub-organizations of one Korean conglomerate company. One thousand employees were randomly and proportionately selected, with 669 useable cases obtained, for a response rate of 67%. The organizational commitment instrument used from the "affective, continuance, and normative commitment" scale (ACNCS) of Allen and Meyer (1990). The "Dimensions of Learning Organization Questionnaire" of Watkins and Marsick (1997) was used to measure learning organization culture. The short form MSQ (Minnesota Satisfaction Questionnaire), developed by Weiss, Dawis, England, and Lofquist (1967), was the third instrument used. Descriptive statistics, correlational statistics, and inferential statistics (ANOVA and t-tests) were used. Organizational commitment (except for continuance) is moderately and positively related to job satisfaction and moderately and positively related to learning organization culture. In addition, learning organization culture is weakly to moderately and positively related to job satisfaction. No differences by age were found. Four-year college graduates are more likely to have higher creating continuous learning opportunities in learning organization culture than graduate school degree holders. Males are likely to have higher affective and continuance organizational commitment than females. Employees working in R&D, Engineering, and Manufacturing (REM) are likely to have higher continuance organizational commitment than do other types of jobs. Employees are more likely to have higher learning organization culture and job satisfaction than assistant managers. Assistant managers have higher continuance organizational commitment than managers. Managers generally have higher organizational commitment, learning organization culture, job satisfaction than assistant managers. They also have higher learning organization culture than employees. Employees who had worked for less than four years in their current job and organization have higher promoting inquiry and dialogue in learning organization culture than those who have worked for ten years or more. Employees in the insurance organization have higher affective organizational commitment, learning organization culture, and job satisfaction than those of the other organizations. Finally, employees of the electronic company have higher continuance organizational commitment in learning organization culture than those of other companies. In summary, this research enables CEOs and HRD and HRM practitioners to view organizational commitment, learning organization culture, and job satisfaction as important variables in exploring diverse ranges of topics related to the workplace. And then, they can diversely apply their management, interventions and practices to fit these diverse characteristics.

• Korean Journal of Ecology and Environment
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• v.48 no.1
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• pp.61-67
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• 2015

This study, which was conducted from Apr. 2013 to Jan. 2014, was carried out as part of a project of making a more detailed ecological zoning map with 1/5,000 scale. The necessity of electronic vegetation map with large scale has arisen in order to make the best use of basic research findings on resource monitoring of National Parks and to enhance efficiency in National Park management. In order to improve accuracy and speed of vegetation research process, the data base for vegetation research was categorized into five groups, namely broad-leaved forest, coniferous forest, mixed forest, rock vegetation and miscellaneous one. And then a vegetation map for vegetation research was created for the research on the site. What is in the database for vegetation research and the vegetation map reflecting findings from vegetation research showed similar distribution rate for broad-leaved forest with 71.965% and 71.184%, respectively. The distribution rate of coniferous forest (16.010%, 15.747%), mixed forest (10.619%, 12.085%), and rock vegetation (0.015%, 0.002%) did not have much difference. In a detailed vegetation map reflecting vegetation research findings, the broad-leaved mountain forest was the most widely distributed with 60.096% based on the physiognomy classification. It was followed by mountain coniferous forest (16.332%), mountain valley forest (15.887%), and plantation forest (3.558%) As for vegetation conservation classification evaluated in the national park, grade I and grade II areas took up 200.44 km2, 61.80% and 108.80 km2, 33.55% respectively. The combined area of these two amounts to 95.35%, making this area the first grade area in ecological nature status. This means that this area is highly worth preserving its vegetation. The high rate of grade I area such as climax forests, unique vegetation, and subalpine vegetation seems to be attributable to diverse innate characteristics of Odaesan National Park, high altitude, low level of artificial disturbance, the subalpine zone formed on the ridge of the mountain top, and their vegetation formation, which reflects climatic and geological characteristics, despite continuous disturbance by mountain climbing.