• Solar Energy
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• v.7 no.2
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• pp.37-53
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• 1987

This study has been prepared for the purpose of developing the system performance prediction method of natural circulation solar hot water system. The storage tank of the natural circulation solar hot water system equipped with flat-plate solar collector is located at higher elevation than the solar collectors. Therefor, the storage tank temperature distribution formed accordance with configuration of storage tank by flow rate of circulating fluid affect system collection efficiency. In this study measure the storage tank temperature distribution with various experimental system under real sun condition and present the theoretical prediction method of the storage tank temperature. Moreover measure the flow rate not only day-time but also night-time reverse flow rate with die injection visual flow meter. Main conclusion obtain from the present study is as follows; 1) The storage tank temperature distribution above the connecting pipe connection position is the same as that of the fully mixed tank and below the connection position is the same as that of stratified tank. 2) The system performance sensitive to the storage tank temperature distribution. Therefore detailed tank model is necessary. Average storage tank temperature can be calculate 3% and storage tank temperature profile can get less than 10% difference with this model system.

• Journal of the Korea Safety Management & Science
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• v.13 no.2
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• pp.243-249
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• 2011

The purpose of the study was to improve of performance for Magnetic Resonance Imaging (MRI) examination in the department of radiology. It was performed DMAIC (Define, Measure, Analyze, Improve, and Control). In the stage of definition, The fifth kinds of CTQ (critical to quality) by the kindness, the waiting time, the examination explanation, the waiting time and the waiting environment were selected by voice of customer. In the stage of measurement, the performed examinations and the reservation waiting time were measured each 1.77 and 1.69 sigma. In the stage of analysis, the potential key causes were determined the limited working hours and the difference of examination time of various entries. In the stage of improvement, MRI were performed with the operating system of 24 hours examination and the optimization of the difference of examination time by among of 30 minutes, 40 minutes, 50 minutes. Finally, the number of examinations and reserved waiting days were measured by each 3.17 and 1.71 sigma in the control stage.

• Human Ecology Research
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• v.51 no.3
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• pp.321-331
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• 2013

The purpose of this study is to develop the scale to measure family health and to analyze the data collected by the survey in order to develop the educational program for healthy family. The sample of this study is taken by 522 housewives who are living in Seoul and are over the age of 40. The data are analyzed according to frequency, percentages, t-test, Pearson's correlation analysis, and Multinomial logistic Regression analysis. The results of this study are as follows. First, the scale measuring family health is developed through interviews with the respondents, preliminary survey, and comments reviewed from specialists. The responses to the scale are significantly different depending on whether they answered their family is healthy or not. Second, minimum family performances for family health are related to the category of social involvement of the family. Third, the types of healthy family are grouped by the responses related to the current state and the status of family health. The number of the type of the worst state-the worst status of family health is the largest, followed by the number of the type of the best state-the best status of family health. Fourth, the important and significant variables that affected the types of family health are psychological variables rather than personal and household-related variables of the respondents.

• International Journal of Advanced Culture Technology
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• v.9 no.3
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• pp.81-85
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• 2021

The purpose of this paper is to measure the relative efficiency of the police agencies in Korea with data collected from 2018 to 2020, using data envelopment analysis (DEA), as put forward by Charnes et al., which is used to construct a scalar measure of efficiency for all police agencies. The results of this study can be used to assist police agencies in delivering better and more efficient services to the community. The analytical results based on DEA identify potentially weak and strong police agencies on policing performance, their efficient benchmarking, and the levels of clear-ups that would make inefficient police agencies efficient. We could suggest that higher levels of the police force are associated with higher performance efficiency against crimes. But, it is a little hard to say that higher levels of the police force can keep the local police agencies efficient without explaining the contribution of other input variables to criminal arrest and prevention. On the other hand, our analysis presents that differences in operating environments and socioeconomic factors do not have a significant influence on the efficiency of local police agencies. But, it is necessary to note that we need to examine the effect of environments and socioeconomic factors on crime to create the better-policing performance.

• International Journal of Computer Science & Network Security
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• v.24 no.1
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• pp.61-70
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• 2024

Cloud Computing is internet-based computing, where the users are provided with whatever service they need from the resources, software, and information. Recently, the security of cloud computing is considered as one of the major issues for both cloud service providers CSP and end-users. Privacy and highly confidential data make many users refuse to store their data within cloud computing, since data on cloud computing is not dully secured. The cryptographic algorithm is a technique which is used to maintain the security and privacy of the data on the cloud. In this research, we applied eight different cryptographic algorithms on Xen and KVM as hypervisors on cloud computing, to be able to measure and compare the performance of the two hypervisors. Response time and CPU utilization while encryption and decryption have been our aspects to measure the performance. In terms of response time and CPU utilization, results show that KVM is more efficient than Xen on average at 11.5% and 11% respectively. While TripleDES cryptographic algorithm shows a more efficient time response at Xen hypervisor than KVM.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.401-404
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• 2008

Bridges are exposed to very severe environment and experience, as service life increased, elevated traffic load and traffic flow, in addition to natural disasters. In comparing to other road structures, bridges may cause more significant damage, such as human-involved accidents, to the society in the event of collapse. A certain level of service shall be necessarily secured to assure the minimum safety of users. The cost for manage and preserve bridges will increase gradually and more restrictions will be loaded to efficiently distribute the limited resources, such as monetary budget and human resource etc. In order to enhance performance and serviceability of bridges with the limited resource, asset management technique has been applied into the bridge management system, which capitalizes the road infrastructures including bridges and assess them in accordance with the government finance report. In the application of asset management, there must be a tool for assess the performance of bridges and this study introduces the basic information on the definition and role of performance measures for asset management for bridges.

• 한국경영정보학회:학술대회논문집
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• 2007.06a
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• pp.807-813
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• 2007

Although firms are adopting strategic performance management systems (PMS) that provide information that allows the firms to identify the strategies offering the highest potential for achieving the firms' objectives, many firms still suffer from making the implementation of PMS a success. The purpose of this paper is to identify those factors that influence the successful implementation of performance management systems. This paper performs a comprehensive literature scrutiny on the implementation factors of PMS including the Balanced Scorecard, Performance Prism, Intellectual Capital Navigation, and Activity-based Costing, as well as traditional performance management systems. The findings of this research will provide useful insights into the anatomy of the success factors for implementing performance management systems and will help management to all the different sized organizations in the different sectors and industries. This paper also provides some future directions for research.

• Asia pacific journal of information systems
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• v.15 no.3
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• pp.41-64
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• 2005

The effects of information quality and the importance of information have been reported in the information Systems(IS) literature. However, little has been learned about the impact of data quality(DQ) on decision performance. Recognizing with this problem, this study explores the effects of contextual DQ on decision performance. To examine them, a laboratory experiment was conducted. Based on two levels of contextual DQ and two levels of task complexity, this study had a $2{\times}2$ factorial design. The dependent variables used to measure the outcomes of decision performance were problem-solving accuracy and time. The results demonstrated that the effects of contextual DQ on decision performance were significant. The findings suggest that decision makers can expect to improve their decision performance by enhancing contextual DQ. This research not only extends a body of research examining the effects of factors that can be tied to human decision-making performance, but also provides empirical evidence to validate and extend DeLone and McLean's IS success model.

• The Journal of Korean Academy of Sensory Integration
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• v.16 no.3
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• pp.23-33
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• 2018

Objective : The purpose of this study is to investigate trend in use of occupational therapy assessment tools used by pediatric occupational therapist. Methods : Survey questionnaire developed for this study were used to for data collection. The questionnaires are divided into 10 area: occupational performance, activities of daily living, education, play, sensory-perceptual, motor and praxis, cognition, social interaction skills, development, and physical examination. Total 105 responses were analyzed using descriptive statistics analysis and frequency analysis. Results : For the general process of evaluation in pediatric occupational therapy, major response on the initial evaluation time was 30~60minutes (41.9%), and major response on the re-evaluation period was 3~6months (41.0%). The major assessment tool for each area Canadian Occupation Performance Measure (55.2%) for occupational performance assessments, Wee Functional Independence Measure (57.1%) for activities of daily living assessments, School Function Assessment (2.5%) for education assessments, Knox Preschool Play Scale (28.6%) for play assessments, Developmental Test of Visual Perception (94.3%) for sensory-perceptual assessments, Bruininks-Oseretsky Test of Motor Proficiency (42.9%) for motor and praxis assessments, Evaluation of Social Interaction (6.1%) for social interaction skills assessments, Denver Developmental Screening Test (92.4%) for development assessments, Clinical Observation (89.5%) for physical examination assessments. Conclusion : The study identified the most assessment tools used for specific area by pediatric occupational therapists. The results can be used as a basic data to educate about pediatric occupational therapy evaluation, as well as to develop new assessment tools in pediatric setting in future.

• Journal of Korean Society of Transportation
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• v.23 no.8 s.86
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• pp.193-202
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• 2005

Due to the importance of SCM(Supply Chain management) in business logistics. many studies related to the SCM performance measurement have been conducted. However, previous SCM performance measurement models have not reflected both ways, operational efficiency and response for market shift. The aim of this research is to suggest a dynamic model to measure SCM performance both with operational efficiency and response for market shift, based on previous SCOR model. To achieve this aim, we developed a cognitive map-based model described eleven KPIs (Key Performance Indicators) with different weight values. And, to measure response level for market shift, we used the concept of entropy-elasticities. Finally, through some actual cases, merits that have no previous models were shown.