• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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• pp.127-129
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• 1988

Square-wave current source inverter drives suffer from torque pulsation and speed variation at low speed. Attempts to minimize these problems, CSI PWM strategies have been reported. It is shown that these PWM strategies are based on unnecessarily restrictive modulation laws. In this paper, trapezoidal PWM strategy for CSI is investigated theoratically by double fourier series and we proposed Harmonic Speed ripple Factor(HSF) that is independent of motor parameters and load conditions. Speed ripple are considered in T-PWM and square wave inverter by HSF. We obtain modulation index(M) and carrier ratio (CR) for minimum speed ripple.

• 무역상무연구
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• 제29권
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• pp.3-37
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• 2006

This writing is for the purpose of investigating the specific character and problem point of China arbitration system which has near 90 years history and overviewing the drift of system improvement which happens recently. The arbitration system of China which traditionally does not acknowledge ad hoc arbitration, unlike most of the other nations that employ The UNCITRAL model law and make it their own legislation, is restrictive to the parties concerned principle of private autonomy considerably. Also the independence of arbitration is delicate, because of a civil characteristic weakness of the arbitral institutions and the intervention of the courts on the arbitration procedure and award. The dual system of domestic and international arbitration which maintains after enforcement of 1994 arbitration law is often to be a primary factor interrupting the development of Chinese arbitration system and making it vulnerable to challenges. The system improvement demand of the recent time reflects this point and makes the arbitration system of China to a international standard rather than now, so it is a desirable direction for China to be as the member of the world economy to be globalization.

• 아동학회지
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• 제29권2호
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• pp.33-56
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• 2008

This study examined effects on children's emotional expressiveness and regulation strategies or maternal attitudes and emotional expressiveness. Participants were 180 children(88 girls) age 3-5, their mothers, and 20 teachers. Results showed boys used more aggressive and girls used more positive coping strategies. Younger children used more aggressive and non-expressive strategies. When mothers had more Permissive and Accepting attitudes, children used more positive coping strategies. When mothers had more Restrictive or Controlling attitudes, children used more aggressive strategies. When mothers expressed positive emotions, children used fewer aggressive and venting strategies. When mothers expressed negative emotions, children used more aggressive and fewer positive coping and non-expressive strategies. Negative maternal emotional expressiveness was an especially influential factor on children's emotional regulation strategies.

• 대한안전경영과학회지
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• 제19권4호
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• pp.43-52
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• 2017

The purposes of this study are to analyze risks of construction step BIM(Building Information Modeling) applied project and improve it. Recently, construction industry has emphasized an importance of BIM for efficient utilization of various information. In the whole life cycle of huge construction project, there are cases introducing BIM and projects applying BIM are gradually increased to the work of construction step. However, the process of communication is not established, so the contents of BIM process of construction step are just showing rough fields and concepts of working utilization, so it's restrictive to utilize BIM actively on constructions step. Through results of case study in this research, constructor risks of BIM business should be efficiently treated with Fuzzy-FMEA that is more precise than existing danger evaluation.

• 가정과삶의질연구
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• 제23권5호
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• pp.181-190
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• 2005

The purpose of this study was to investigate the characteristics of leisure behavior of the five-day workweek company employees for developing leisure facilities in residential environment. The questionnaire survey was used. The subjects of questionnaire survey were 247 staffs of 4 banks. The questionnaire consisted of leisure time, the cost of leisure, consciousness of leisure, actual condition and need of leisure activities and spaces, leisure satisfaction and limitation on leisure. Frequency, percentage, and mean, correlation, $x^2-test$, and factor analysis were used for data analysis. The major results were as follows. 1) Leisure is necessary to strengthen the unity of family and cultivate the sentiment. 2) The degree of satisfaction of leisure facilities was lower than neutral. The satisfaction of leisure facilities related with cost, time of leisure, information of leisure facilities and program, and leisure environment. 3) Present leisure behavioral characteristics were restrictive and passive. However, the subjects showed hopes to increase their leisure activities and to engage in diverse forms of leisure in the future. Also, they showed an increased desired ratios in participating in each leisure activities. 4) In terms of location, they needed leisure facilities which was closer to their house.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2009년도 추계학술대회 및 정기총회
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• pp.76-95
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• 2009

In the fungal genus Cordyceps, the type species Cordyceps militaris produces bioactive ingredients and exhibits medicinal effects as a Traditional Chinese Medicine (TCM), The fruiting bodies of C.militaris have now been mass-produced artificially and used as functional food and medicine in China. The unstable variation in forming fruiting body is however a key restrictive factor in industrial production. The genetic study on in vitro stromata formation of C. militaris has rarely been carried out. Here, we report the effects of genetic variation including the mating system on perithecial stromata formation of C. militaris. Monoconidial isolates which have both MAT1-1-1 and MAT1-2-1(genotype MAT1-1/2) could produce stromata. While the isolates only have either MAT1-1-1 or MAT1-2-1 (genotype MAT1-1 or MAT1-2) failed to produce stromata. Despite obvious heterothallism, homothallism was occasionally observed in a few isolates of C. militaris. High genetic variation was observed amongst the different monoconidial isolates of C. militaris. The unstable variation or lose of fruiting body formation was found to be caused by the inner-species high genetic variation of C. militaris. These results also indicated that C. militaris sexually behaved as both heterothallic and homothallic and required two mating type compatible in the same culture in order to produce regular clubshaped perithecial stromata.

• 대한전기학회논문지:시스템및제어부문D
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• 제54권12호
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• pp.698-704
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• 2005

Passive suspensions with fixed design constants are very restrictive in the inherent suspension problem, the trade-off between the ride quality and the suspension travel. Active suspensions are used to solve some drawbacks of passive suspensions. In this paper, we propose a controller design for vehicle active suspensions considering variable driving conditions. Our controller estimates the current driving conditions by detecting the road frequencies gotten from Fourier Transform and decides which factor must be emphasized between the ride quality and the suspension travel. In one case of focusing on the ride quality, we use the skyhook control law and in the other case of focusing on the suspension travel, the double skyhook control law is used. The control law modified by various road situations outputs the reference force value the electro-hydraulic actuator in active suspension system must generate. To track the reference force, we adopt the sliding control law which is very useful in controlling the nonlinear system like the electro-hydraulic actuator.

• Archives of Plastic Surgery
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• 제32권3호
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• pp.375-380
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• 2005

Furlow palatoplasty has been favored by many plastic surgeons as the primary treatment for the velopharyngeal insufficiency associated with submucous cleft palate. The purpose of this article is to introduce an efficacy of Furlow palatoplasty and speech therapy performed on patients who were diagnosed belatedly as having submucous cleft palates. From 2002 to 2004, four submucous cleft palate patients over 5 years of age with velopharyngeal insufficiency received Furlow palatoplasty. The patients were evaluated through the preoperative perceptual speech assessment, nasometry, and videonasopharyngoscopy. Postoperatively, two patients achieved competent velopharyngeal function in running speech. One of the remaining two could achieve competent velopharyngeal function with visual biofeedback speech therapy and the other could not use her new velopharyngeal function in running speech because of her age. Speech therapy can correct the articulation errors and thus improve the velopharyngeal function to a certain extent by eliminating some compensatory articulations that might have an adverse influence on velopharyngeal function. This study shows that Furlow palatoplasty can successfully correct the velopharyngeal insufficiency in submucous cleft palate patients and speech therapy has a role in reinforcing surgical result. But age is still a restrictive factor even though surgery was well done.

• 보건행정학회지
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• 제9권4호
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• pp.120-139
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• 1999

The objectives of this study were to examine the utilization patterns of oriental medical care and to discover problems in its delivery. The data for this study were collected from a questionnaire survey mailed out from March 10 to April 9 1999 to 6.346 oriental medical clinic. The questionnaires were then distributed to two patients in each clinics. Of these questionnaires. 670 were completed and returned. The major statistical methods used for the analysis were the t-test. ANOVA, and x$^2$-test. The major findings are as follows: 1. Respondents reported visiting oriental doctors twice as often as they visited western doctors(All those completing the survey received the questionnaire at oriental medical clinics). 2. The number of reported visits to oriental physicians according to among gender, age, marital status, education, income and residence. Males, married respondents, the elderly and the residents of rural areas visited oriental physicians more frequently than females, singles, younger respondents and urbanites. Those people belonging to the middle income class and middle education level also more frequently visited oriental physicians. 3. There are several factors that restrict the utilization of oriental medical care, such as the limitation of the scientific diagnostic instrument use commonplace reliance upon western medical techniques, and the perception of high price for oriental medical care. It is very important to focus oriental medical care onto the fields of acupuncture, circulatory system disease, musculoskeletal system ailments, etc. to improve the utilization of oriental medical care. Other policies for the improvement of oriental medical care include the standardization of price, quality and quantity of oriental medicine.

• 한국산학기술학회논문지
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• 제8권1호
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• pp.10-17
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• 2007

자동차 미끄럼방지 장치의 최적 제어를 위해서는 유압 모듈레이터 특히, 솔레노이드 밸브에 대한 정확한 동특성 해석이 필요하다. 그러나, 현재까지 진행된 대부분의 연구들은 솔레노이드 밸브 자체만을 고려하였기 때문에 실제 자동차 미끄럼방지 장치에 제한적으로 적용되었다. 본 연구에서는 유압 모듈레이터에 작용하는 압력을 고려한 솔레노이드 밸브의 동특성 해석을 위하여 실험과 이론 해석을 실시하였다. 작동 압력이 솔레노이드 밸브의 동특성에 끼치는 영향을 정량적으로 해석하였고 설계인자를 변화시키면서 성능향상 방안을 제안하였다. 따라서, 본 연구에서 수행한 솔레노이드 밸브 동특성 해석결과는 자동차 미끄럼방지 장치의 최적 제어 기준으로 활용할 수 있을 것이다.