• Journal of Korea Game Society
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• v.17 no.4
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• pp.137-148
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• 2017

Since the power consumption of data centers is large and computer serves take a large portion of it, there have been much research on the power saving of servers in various ways recently. Among the units of severs CPU is one of major power consuming units. In this paper, a method of client-server assignment for minimizing the CPU power consumption of servers in a game server cluster is proposed. We model the client-server assignment problem as an optimization problem, and find a solution to the problem using a simulated annealing-based technique. One of major features of our method is to select a proper operating frequency according to the amount of load on a server. The selection of a lower frequency in case of low load will result in reducing power consumption. To our survey, little research on client-server assignment in consideration of power consumption has been carried out.

• The Journal of the Acoustical Society of Korea
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• v.36 no.3
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• pp.179-185
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• 2017

The problem that occurred in the design/fabrication/testing of the wideband transmitting power amplifier for an embedded active SONAR (Sound Navigation and Ranging) system operating underwater was analyzed and the solution of the problem was proposed in this paper. Wideband acoustic SONAR systems had been developed in order to improve the underwater detection performance. The underwater acoustic transmission system had been also developed to achieve the wideband SONAR system. In this paper, the wideband acoustic transmission signal was generated using a 2 Level sawtooth type Class D PWM (Pulse Width Modulation) which was not complicated to implement. When the sonar signals having two or more frequencies were simultaneously generated, parasitic frequencies were added to the original signals by integer multiples of the frequency difference of the original signal. To cope with this problem, we proposed a way to remove the parasitic frequency from the source signal through modeling and simulation of the implemented power amplifier and PWM control hardware using MATLAB and Simulink.

• Journal of the Korea Society of Computer and Information
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• v.18 no.2
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• pp.69-76
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• 2013

Reader-to-reader interference in RFID system is occurred due to the use of limited number of frequencies, and this is the main cause of read rate reduction in the passive RFID tags. Therefore, in order to maximize the read rate under the circumstances of limited frequency resources, it is necessary to minimize the frequency interference among RFID readers. This paper presents a hybrid FDM/TDM constraint satisfaction problem models for frequency interference minimization problems of the RFID readers, and assigns optimal channels to each readers using conventional backtracking search algorithms. A depth first search based on backtracking are accomplished to find solutions of constraint satisfaction problems. At this moment, a variable ordering algorithm is very important to find a solution quickly. Variable ordering algorithms applied in the experiment are known as efficient in the graph coloring. To justify the performance of the proposed constraint satisfaction problem model, optimal channels for each readers in the passive UHF RFID system are allocated by using computer simulation satisfying various interference constraints.

• Journal of Community Nutrition
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• v.1 no.1
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• pp.44-51
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• 1999

The purpose of this study was to compare dietary behavior and food intake in relation to physical complaints, such as farmer' syndrome(FS) and gastro-intestinal(GI) problem among Korean farmers. The questionnaire was composed of 24 Cornell Medical Index (CMI), 8 farmers' syndrome, and 5 GI problem questions. Food intake data was gathered by the semi-quantitative food frequency method. The subjects(male 226, female 415) who had FS and Gi problem were 12./8% and 8.3%, respectively. The physical complaints were higher in female and the elderly group. In the FS group, lower activity was seen that in normal groups. The lower health status and fatigues were found in the physical complaint groups. Dietary behavior showed low appetite in the physical complaint group, irregular lunch in FS, and irregular breakfast in GI problem group. Changes in dietary behavior were shown in the aspects of lower amount of intake quantity(40.8%), lower consumption in fat(32.8%) and salty(38.8%) foods, and diverse food items(47.8%). Quantity of food consumed was significantly different withing groups with FS. Kinds of food consumed, intake of protein source foods, milk and calcium and total animal foods were lower in the FS group. But milk and calcium source food and all animal food intakes were higher in the GID problem group. The results suggest that dietary behavior and food intake differ within the group of physical complaints.

• Journal of Families and Better Life
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• v.7 no.1
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• pp.1-14
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• 1989

The purpose of this study was to identify the problems in the consumption life of household over the family life cycle so that they would support to select the consumer education subjects and the establish the long-term household plan. For these purposes, a survey was conducted using questionnaire. The data used in this study included 562 homemakers living in Seoul. Statistics used for data analysis were frequency distribution, Mean, Percentile, One-way Anova, Scheffie-test, Multiple Classification Analysis. Major findings were as follows; 1) In the level of the problems in the consumption life of household, housing problem, durable goods problem, healthy-medical problem and child education problem area were in the low level. Leisure problem and properties management problem area were in the high level. 2) The problems in the consumption life of household differed significantly over the family life cycle. 3) When controlling family monthly income and education level of husband was compared with not-controlling them, the influences of family life cycle on the problems in the consumption life were as follows. (1)At housing problem area, the effect of the FLC was higher in controlling them than not-controlling them. (2) At other problems the effects of the FLC was lower or same in controlling them than not-controlling them.

• The Journal of Korean Society for School & Community Health Education
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• v.19 no.3
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• pp.29-39
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• 2018

Objectives: The purpose of this study was to identify the effects of college student gambling experience on the gambling problems. Methods: The study included 260 students from four-year universities in Seoul and Gangwon Province, and collected data from March 1, 2018 to March 31, 2018. The data were analyzed with the SPSS 23.0. Results: First, gambling experience showed high frequency among males (68.5%), 21 years of age and older (45.5%), boarding house (66.1%), and two or more siblings (40.5%). Second, the gambling problem based on the experience of gambling was statistically significant in academic problem, interpersonal relationship, and gambling control. Third, the mental health of the subjects was highly correlated by interpersonal relationship, gambling recognition and academic problem. Also, academic problem was highly correlated in order of gambling control and interpersonal relationship. Fourth, effects of gambling experience on the gambling problems were identified as gambling control, interpersonal relationships, gambling awareness and mental health. Conclusion: Recognize the seriousness of the gambling problem of college students in order to solve the gambling problem, the government, communities and universities should actively promote the harmful effects of gambling and provide regular mental health. education at universities.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1989.04a
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• pp.17-21
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• 1989

SSI2D/3D is a computer program to calculate dynamic stiffness matrix of the foundation for soil-structure-interaction problem in frequency demain. It is written in FORTRAN 77 and applicable to two or three dimensional situations. In this paper the program structure is summarized. Two examples aye shown to demonstrate the possibilities of the Boundary Element Method applied to dynamic problems in infinite domains.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.292-295
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• 2003

In this paper, we propose an approach which contains with constructing a bibliography information database, extracting the fields of research, and researching trend of them, using data mining. To apply our approach to IEICE Technical Report (nonlinear problem society), the database was constructed based on its report, keywords were analyzed using the frequency analysis and the association analysis, and we discussed about the result. We could extract some field of research from the result.

• Journal of Ocean Engineering and Technology
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• v.17 no.1
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• pp.80-85
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• 2003

In this study, we developed an analysis method of plate forming by induction heating, verifying the effectiveness of the present method through a series of experiments. The phenomena of the induction heating involves a 3D transient problem, coupled with electromagnetic, heat transfer, and elastoplastic large deformation analyses. To solve the problem, or present an appropriate model and an integrated system. Using the present analysis model, or can estimate the plate deformation in heating without experiments and simulate the plate bending process of induction heating.

• Journal of Korean Institute of Industrial Engineers
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• v.15 no.2
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• pp.1-10
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• 1989

This paper deals with a single-facility multiproduction model concerning the basic cyclic scheduling. The aim is to obtain the production order of each product in a cycle and the cycle frequency for minimizing the setup costs and inventory carrying costs of all products. The problem is formulated by LP and it shows that the optimal solution derived dominates the solution of non-cyclic scheduling model on some conditions.