• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.455-458
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• 2005

This study compares the concrete using natural sand with the concrete using crush sand for the examination for the properties of a concrete. In the fresh concrete, the concrete using crush sand has less of the quantity of consistency, the content of air, and bleeding than the concrete using natural sand, and the concrete using crush sand has faster setting time than the concrete using natural sand. In hardening concrete, the concrete using crush sand has higher compressive strength and tensile strength than the concrete using natural sand because minute particles fill up a gap. Drying shrinkage of the concrete using natural sand is less than the concrete using crush sand.

• Journal of the Korea Society for Simulation
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• v.3 no.1
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• pp.43-53
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• 1994

With remarkable progress of hardware technologies, multiprocessor systems equipped with thousands of processors will be available in near future. In order to increase the performance of these systems, many processor allocation algorithms have been proposed. However, few studies have been conducted in order to compare the performance of these algorithms. In this paper, simulation techniques are used in order to compare the performance of the processor allocation algorithms proved to be useful. These are: an algorithm using equipartion, an algorithm using average parallelism, an algorithm using execution signatures, and an algorithm using the number of tasks in a task precedence graph. Simulation shows that the algorithm using execution signatures performs best while the algorithm using average parallelism performs worst with small allocated processors. Surprisingly, the algorithm using equipartition performs well despite the fact that it has smallest overhead. Overall, it can be recommended that the algorithm using equipartition be used without any execution history and that the algorithm using execution signatures be used with some execution history.

• Korean journal of food and cookery science
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• v.3 no.2
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• pp.100-110
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• 1987

The effectiveness of hot thermal retention system which was being used in 3 general hospitals, A,B, and C in Seoul was evaluated in terms of time-temperature relationship. The results of the study were summrized as follows: 1) The serving temperature of steamed rice using insulated bowls were significantly higher than those of using no thermal support. 2) The serving temperatures of soup using insulated bowls were significantly higher than those of using no thermal support. 3) The serving temperatures of meat of fish dishes using insulated bowls as well as warmer cabinet were significantly higher than other groups such as using warmer cabinet only, using insulated bowls only, and using no thermal support. 4) However surveyed serving temperatures of meals using hot thermal retention system were not whthin the range of temperature criteria.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.6
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• pp.402-407
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• 2004

This paper proposed a new speed sensorless control method for AC servo motor, which is based on the current observer. Recently, the study in the estimation using a observer is being widely progressed. In order to prove the superiority of the current observer, we made a comparison between the simulation using current observer and that using Luenberger observer. And also, a comparative experiment of the speed control of the AC servo motor using a sensor and using current observer has been executed. The experiment result shows that the estimation using current observer is superior to the estimation using Luenberger observer or to the speed response using a sensor.

• Journal of the Korean Society of Physical Medicine
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• v.18 no.3
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• pp.113-119
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• 2023

PURPOSE: This study aimed to determine the effects of using a smartphone in the sitting position on the pelvic posture and the low back pressure pain threshold (PPT). METHODS: Thirty participants (15 women and 15 men) were recruited for this study. The participants were asked to sit in a normal sitting position without using a smartphone, followed by sitting while watching a video using a smartphone. The pelvic posture was measured using the back range of motion II (BROM II) device and a palpation meter. We measured PPT using the digital pressure algometer. RESULTS: Pelvic posterior tilting was significantly greater when sitting while using a smartphone relative to sitting without using a smartphone (p < .05). There was no significant difference in the height of the iliac crest when sitting while using a smartphone compared to sitting without using a smartphone (p > .05). The PPTs of L1, L3, and L5 were significantly lower when sitting while using a smartphone relative to sitting without using a smartphone (p < .05). CONCLUSION: Based on these results, it can be concluded that frequent smartphone use while sitting may potentially increase the risk of developing low back problems.

• Journal of Korean Academy of Nursing
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• v.30 no.1
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• pp.7-17
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• 2000

The purpose of this study is to affect health improvement of adolescent, to understand behavioral causes follow adolescent's drug abuse, to understand recovery and rehabilitaton process of adolescent drug abuser. The data are collected through open questionnaire and interview of 25 adolescents from the experienced drug abuse 16 students(male 8, female 8) in two vocational high schools and admissing adolescents 9 person in Alcohol-Drug Addiction Care Centre in Seoul from June 28th to August 31st, 1994. The collected data are arranged and explained through categorizing method stated contents about motives, causes, experiences and effected behaviors for using the drugs of drug abuser adolescents. DRUG USING MOTIVATION They are almost first son and daughter in their family. In their conversation person, male converses to their mother well, but female does not converse to their parents include family. Both groups respond positively to companionship and attitude to other, but negatively to self-confidence and actualizing attitude. They hope always peace of family and want to do their best for their life. In school group, hard and difficult things are school life and family problems, also using the drugs for resolving the them. About drug using behaviors, male responds to bad habbit and shamfull, but female is unconcerned with drug using attitude. The first background of drug using, male gets to use because of curiosity and to be induced from friends or seniors, but female gets to use for feminine beauty(thin body) and escape from reality. Used the drugs, male uses frequently Bond, Butane-Gas among inhalation materials and also marijuana, but female uses various diuretics. The times of drug using, both groups repond to use during the chaging of emotion or filling with stress. The place of drug using, both groups take drugs in vacant houses or in the mountain. The frequency of drug using, they use almost once in a day and they use mostly alone or drug user in friends. Experienced mental changing after drug using, which is fantasy, ecstasy, anxiety and suicidal feeling, and experienced physical changing after drug using, which is elevating sense, headach, abdominal pain, dyspnea and chaging of skin colour and reddish. They coincide with inconvenience feeling due to drug using. RECOVERY AND REHABILITATION PROCESS OF DRUG USING ADOLESCENTS The reason for reforming drug using behavior and attitude, both groups respond to reforming for oneself and social life. The difficult things during the stop to using drugs, all of them responed to family problems, friends problems and temptation and impulse. As for stop to using drug, they need good advise, understandable attitude and family love. But they do not need to be stigmatized, scolding, over protect and ridicule of friends. Also they entreat continuous understanding, advise, concern and the method for resolving stress. For the friends to want to use the drug, they will talk about the stories of their personal experiences and for the friends to stop to using the drug, they will consider for them how to stop. From the theses results, drug users understand personal problems due to drug using, and consider about why to stop and how to stop. Also drug users need to resolve the family problems, personal problems, stress and temptations or impulses. Accordingly this paper suggests that drug users in adolescents need understandable and acceptable atitudes, loving and tenderness, continuous advice and concern, and hopes for life.

• The Journal of Korean Society for School & Community Health Education
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• v.12 no.1
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• pp.45-58
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• 2011

Objectives: The purpose of this study is to analyze the fators affecting Internet addiction among adolescents in an area. Methods: By using cluster sampling, 2,479 participants representing 22 elementary school, 11 middle school, 7 high school students in a county of the Chungcheongnam-do. Data was analyzed by SPSS 12.0. using t-test, F-test, chi-square test, Pearson correlation coefficient and multiple regression. Results: Internet addiction positively correlated with high school students(dummy variable), Internet-connected computers in PC Game Room(dummy variable), Internet using time(weekday) and Internet using time(weekend). Internet addiction negatively correlated with Internet-connected computers in school(dummy variable), Internet-connected computers in friend's house(dummy variable). For the male students, Significant factors affecting Internet addiction were eating habits, Internet-connected computers in friend's house, Internet using time(weekend). For the female students, Internet using time(weekday) and Internet using time(weekend) were significant. For the elementary school students, Significant factors affecting Internet addiction were Internet using tine(weekday) and Internet using time(weekend). In the case of the middle school students, Internet using tine(weekday), Internet using time(weekend) and eating habits were significant. but, the high school students, Internet using time(weekend) was significant. Conclusions: Students who spend more time in the internet have higher tendency to become addicted to the internet. Therefore, it would be necessary to develop program to prevent internet addiction.

• Journal of Korean Elementary Science Education
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• v.29 no.2
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• pp.113-123
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• 2010

The purpose of this study is to investigate the effect of instruction using movies on the attitude toward science and learning achievements in Elementary Students. For this study, it was chosen two classes of the fifth grades in H elementary school in Gyeonggi province. One class was an experiment group and the other class was a control group. Instruction using movies was applied to the experimental group and instruction using data of site T-nara that most teachers are using usually present was applied to the control group. Instruction using movies composed of seven steps was administered during the school hours. The results of this study were as follows. First, instruction using movies was positive effect in the Attitude toward Science. Second, there was significance between the score of the learning achievements of the experimental group and control group by instruction using movies. Third, there were many positive reactions of students about instruction using movies.

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.2
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• pp.81-98
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• 2002

The condition of initial movement far the river bank protection using rip rap is a limit condition beyond which the lining is progressively destroyed as the separate elements are removed by the flow. In the case of the river bank protection using gabion mattress, however, after the initial movement the containment offered by the mesh remains. A new situation of equilibrium with a deformed river bank protection using gabion mattress is obtained, allowing it to withstand more severe conditions without compromising the resistance and without further deformation. Shield's coefficient for the river bank protection using gabion mattress is twice the value of that fur river bank protection using rip rap. This means that with the same hydraulic behavior conditions, the average dimension of the rocks to be used in the river bank protection using gabion mattress is half that of river bank protection using rip rap rock. When the same size rocks are used the allowable velocity for the river bank protection using gabion mattress is more than twice, even as much as 3 or 4 times that for river bank protection using rip rap.

• Korean Institute of Interior Design Journal
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• v.25 no.3
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• pp.31-39
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• 2016

This study is aimed to increase the possibility of using the Christopher Alexander's pattern language. The methodology of this study is (i) to analyze the pattern language by using the network analysis tool in order to understand the complicate network structure of the pattern language, and (ii) to apply the Alexander's method of using the pattern language by using the network analysis tool (Gephi) and to examine the feasibility of the network analysis tool as a tool for using the pattern language. Firstly, as a result of analysing the pattern language, (i) the pattern language classified by pattern number is distinguished by the patterns of towns, buildings and construction, among which the pattern of buildings plays a key function in the networks; (ii) the buildings functions a medium connecting between the towns and the construction; and (iii) the pattern language is divided into 6 sub-modules, through which the user can select a pattern. Secondly, the result of using the network analysis tool as a tool for using the pattern language (i) suggests the new method of using the pattern language by using the network analysis tool (Gephi); (ii) makes it possible to easily figure out the characteristics of the links between the patterns; and (iii) increases the completeness of the pattern language by making it easy to find out the sub-patterns in selecting a pattern.