• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.2
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• pp.227-237
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• 1998

A numerical simulation has been carried out for the automotive air conditioning system. The purpose of this simulation is to present the methods for simulating car air conditioning components, systems and cool-down performance by computerized mathematical model and to analyze the performance of A/C system. In analyzing the heat exchanger(evaporator and condenser), the finite volume model which has a merit in predicting the temperature field in detail because it can consider partial variation of thermal property and heat transfer coefficient is used. In analyzing the compressor, the polytropic approach which regards the actual compression process as a reversible polytropic process is employed. In analyzing vehicle passenger compartment, the thermal network is employed to simulate the car cool down process. This A/C system program can be used for analyzing a component performance when a component is alternated or designed and for analyzing the engine cooling system when A/C system is operated.

• Culinary science and hospitality research
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• v.13 no.1 s.32
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• pp.75-86
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• 2007

This study was carried out to find out the effect of food hygiene awareness on kitchen employees' performance in the banquet cuisine of five-star hotels in Seoul. 279 kitchen employees were asked to fill out the questionnaire, and the collected data were analyzed by SPSS package(version 11.0). First, results of analysis on food hygiene showed that there were four factors, each respectively named as, food security regulations, food storage, period of circulation of food, and food safekeeping. Second, after analyzing each item in whole according to each of the factors, the average degree of priority on food hygiene in general was 4.52. Results according to each of the elements showed that food security regulations(4.56) and period of circulation of food(4.55) were considered as a priority. After analyzing the difference between the degree of priority and degree of performance according to each of the factors, it was found out that the latter was significantly lower than the former in all factors. Third, after analyzing the difference of food hygiene priority in accordance with general characteristics, statistically significant difference was only shown in education(F=3.308, p<0.05) and class(F=4.418, p<0.01). Fourth, after analyzing the difference of food hygiene performance in accordance with general characteristics, the only significant difference was found in food security regulation of education(F=4.418, p<0.01) and food security regulation of class(F=3.859, p<0.01). Fifth, after analyzing the effect of cook's awareness of priority on food hygiene on the degree of performance, it was found out that the awareness of priority on food hygiene had a positive effect(+) on the degree of performance. Therefore, we can conclude that as kitchen employees recognize the priority on the food hygiene better, their degree of performance was higher.

• Journal of applied mathematics & informatics
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• v.26 no.1_2
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• pp.235-249
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• 2008

On-demand routing protocol in ad hoc network is that establishes a route to a destination node only when it is required by a source node. But, it is necessary to reestablish a new route when an active route breaks down. The reconstruction process establishes another route by flooding messages from the source to the destination, cause not only heavy traffic but also long delays in route discovery. A good method for analyzing performance of protocols is important for deriving better systems. In this paper, we suggest the numerical formulas of a representative on-demand routing protocol AODV, ARMP, and RRAODV to estimate the performance of these routing protocols for analyzing the performance of these protocols. The proposed analytical models are very simple and straightforward. The results of analysis show good agreement with the results of computer simulations.

• Journal of Korea Multimedia Society
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• v.18 no.12
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• pp.1501-1508
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• 2015

In this paper, we describe a case study to improve performance through the load testing of multi-tired system for financial accounts before the system opening. The load test was conducted after the data collection tools(Performance Monitor, DB PSSDiag) were installed. By analyzing the collected log, we were able to identify the main sector requiring performance improvements among the presentation tier, web tier, business logic tier and data tier. The ASP.NET server-down on the web tier could be improved by modifying the parameter values in the configuration file. Some server downs occurred on the business logic tier when a large number of users access at the same time, were more difficult to be solved. By analyzing the hang-dump at the server-down time, we were able to find a process that caused the problem. and we had to modify the relevant codes. For major performance improvements of the data-tier, indices of some queries was optimized by using the built-in DBMS query analyzer, after analyzing the log of long-response-time queries. The problems and solutions considered in this case study will be a reference for the performance improvement of a multi-layer system with the similar structure.

• Journal of the Ergonomics Society of Korea
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• v.33 no.1
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• pp.27-37
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• 2014

Objective: This study aims to improve human performance by analyzing the operators' tasks and providing input data on the composition of future SMART operators. Background: SMART is a nuclear reactor for export which needs operators who can satisfy both safety and economic feasibility. Therefore, this study is fundamental research on the composition of operators and this research analyzed SMART tasks in terms of human safety performance. Method: After analyzing 10 SMART EOG in hierarchical task analysis, this study classified task performance types according to task requirements of NUREG-0711 (Rev.3). Results: This study found the task frequency of SMART EOG and 12 operating task types. Conclusion: This study expects that human performance can be improved by analyzing the personal errors, which have the highest task frequency among 12 operating task types. Application: The results of this study can be applied as base data when licensing needs to be acquired.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1994.04a
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• pp.627-632
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• 1994

This study suggests the contingency framework understanding the implementation of NIMT and conducts empirical analysis using survey data. The main objectives of the thesis are as follows : (1) analyzing the relationship between adaptation requirements and organizational adaptation efforts. (2) analyzing the relationship between organizational adaptation efforts and implementation performance, and the moderating effect of the adaptation requirements. (3) analyzing the relationship between organizational adaptation efforts and organization characteristics(organization size, technical capability, top management support). A field study was undertaken to test the hypothesized relationships among adaptation efforts, adaptations requirements, organization characteristics, implementation performance. Data were collected from 52 NMT implementation projects of 45 machine tool, metal component firms. The emprical relflts indicated that adaptation requirrnents, organization characteristics were significantly related to organizational adaptation efforts and adaptation efforts can significantly improve implementation perfomance, but the moderating effect of adaptation requirements on adaptation efforts and implementation performance was not supported.

• Journal of Korean Elementary Science Education
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• v.21 no.2
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• pp.227-239
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• 2002

The purpose of this study was to improve the practice of performance assessment in elementary science education and to support it according to the levels teachers' concerns. So this study was conducted by applying CBAM which is based on teachers' concern, which was designed for the investigation of the elementary science teachers' concern, their performance level, intellectual understanding, status of performance. and stage oi awareness and the connections between these factors. The study involved 311 elementary school teachers in the city of Seoul. The result of this study was as follows: First, the stage of teachers’ concerns performance assessment in science marked 49.5％, indicating that about half of the teachers was staying on the informative stage which could be generally occurring in the beginning of performance the curriculum innovation. The level of performance marked 33.8%, which was regarded as the stage of elaboration. For the category of intellectual understanding, most of the teachers didn’t fully understood the performance assessment. Regarding the status performance, 90.4％ of the teachers were implementing the assessment at the state of knowing the purpose of it. However. 40.5% of the teachers didn't fully understand the specific characteristics of the assessment. Also, the results of analyzing the teachers’ awareness on science performance assessment indicated that they have slightly positive positions. Secondly, the result of analyzing the stages of concerns for the assessment, based on the elementary school teachers' personal background, levels of implementation, and their intellectual understanding showed that the concerns were significantly different with the categories of their workplaces(p<.05). Finally, the result of analyzing the relationship among the concerns for the science performance assessment, levels of implementation and intellectual understanding indicated that there were significant differences in levels of implementation with the degree of intellectual understanding (p<.001).

• Knowledge Management Research
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• v.12 no.4
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• pp.55-75
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• 2011

Scant attention has been given to analyzing how knowledge sourcing strategies affect firm performance in SMEs and what are the differences between SMEs and large firms in the patterns of knowledge sourcing strategies adoption. This study attempts to advance the current literature by examining the impact of knowledge sourcing strategies on SMEs performance. The empirical segment of our work is based on data on knowledge sourcing strategies of SMEs and organizational performance from a sample of 166 Korean firms. Our results indicate knowledge sourcing adoption patterns of SMEs are different from large firms. In addition, the results confirm that substitutability between internal- and external-oriented, person- and external-oriented sourcing strategies. This study sheds new light on knowledge management (KM) research by identifying the relationship between knowledge sourcing strategies and SMEs performance.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.738-746
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• 2009

The purpose of this study is to develop the web-based system for work performance analysis(WPAS). The need of work performance analysis system has already been suggested in many previous researches on the computerization of the performance measurement in the construction site by using the indicators such as time, cost and quality. However, they had focused on measuring or analyzing the result when the project would be over. The WPAS suggests three indicators - work reliability, work effectiveness and work efficiency - to manage the performance of the construction site. It can help the manager more easily recognize the status of on-going work in the construction site by measuring and analyzing the work reliability rate, the work effectiveness and work efficiency every day. This research includes the procedures for WPAS measurement process, database structure of WPAS which was analyzed by the IDEF0 and the data flow diagram. Finally, this research introduces the result of WAPS's case studies and validation in the Korean construction site.

• KIPS Transactions on Software and Data Engineering
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• v.4 no.2
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• pp.77-82
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• 2015

Big Data technology has been attracted much attention in aspect of fast data processing. Research of practicing Big Data technology is also ongoing to process large-scale structured data much faster in Relatioinal Database(RDB). Although there are lots of studies about measuring analyzing performance, studies about structured data loading performance, prior step of analyzing, is very rare. Thus, in this study, structured data in RDB is tested the performance that loads distributed processing platform Hadoop using Apache sqoop. Also in order to analyze the influence factors of data loading, it is tested repeatedly with different options of data loading and compared with data loading performance among RDB based servers. Although data loading performance of Apache Sqoop in test environment was low, but in large-scale Hadoop cluster environment we can expect much better performance because of getting more hardware resources. It is expected to be based on study improving data loading performance and whole steps of performance analyzing structured data in Hadoop Platform.