• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제52권9호
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• pp.448-453
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• 2003

In this paper the controlled closing algorithm of the circuit breaker for isolated capacitor banks is proposed. The characteristics of circuit breakers such as RDDS(rate of decrease of dielectric strength) and a mechanical operating tolerance should be also taken into account to locate contact touch instants around voltage zero. The analysis results on the voltages across circuit breaker terminals upon closing operation play an important roles to describe the suggested method. The simulations carried out in order to verify the performance of this method show that the closing instants obtained from the proposed method provide a good suppression effect on the closing transients for both single and back-to-back capacitor banks.

• Journal of Oral Medicine and Pain
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• 제9권1호
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• pp.93-101
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• 1984

The author has studied mandibular opening and closing movement patterns using mandibular kinesiograph in order to make basic data that is necessary to diagnose the mandibular movement function. The 83 normal subjects, who were students of the school of dentistry. Kyunpook National University and Daegu Junior Health College, were selected according to sampling criteria. The results were as follow : In the sagittal plan, crossover pattern had the highest incidence in male (72.7%) and female(76.8%). There was no significant defference of distribution of habitual closing movement patterns between male and female.(p>0.05). There were difference between each patterns.(p<0.01) In the frontal plane, there was no difference of distribution of male's opening and closing movement patterns between habitual and maximum velocity (p<0.05),but difference between each subjects. (p<0.05) In the frontal plane, there was no difference of distribution of habitual opening and closing movement patterns between male and female.(p<0.05) In the frontal plane, the average number of habitual opening and closing pathways cross the midline was greater than that of maximum velocity.(p<0.05) The average of the maximum mandibular movemet velocity of male was greater than female in opening and contact(p<0.01) and there was no difference between male and female in closing.(p>0.05)

• 대한안전경영과학회지
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• 제22권3호
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• pp.15-21
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• 2020

This study analyzed the evacuation time in indoor stadiums when exits that automatically open/close when the fire sensor is triggered are installed as a means to improve the problem of closing certain exits. Firstly, when spectators on the 2nd floor stands exit through the 1st floor exits, the RSET of all inhabitants was 529.8 seconds when the automatic opening/closing exits are broken and employees are not present. Secondly, when spectators on the 2nd floor stands exit through the 1st floor exits, the RSET of all inhabitants was 445 seconds when the automatic opening/closing exits with 750mm width are working but employees are not present. Lastly, when spectators on the 2nd floor stands exit through the 1st floor exits, the RSET of all spectators was 337 seconds when the automatic opening/closing exits with 1,500mm width are working and employees are present. As a result, it was revealed that the evacuation time is shortened when the automatic opening/closing exits are working. Additional comparative studies with actual simulations of people evacuating an indoor stadium and firefighting simulations considering smoke flow are necessary.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제24권1호
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• pp.51-58
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• 2018

Purpose: In this study, through the comparison of the pressure fluctuation and air exchange volume in negative isolation room according to the type of the door and door opening/closing speeds, which is one of the main factors causing the cross contamination of the negative pressure isolation room, establishes standard operating procedures to prevent cross contamination in high risk infectious diseases and isolation room design. Methods: In this study, the air flow each of the room is analyzed using ANASYS CFX CODE for flow analysis. In addition, the grid configuration of the door is constructed by applying Immersed Solid Methods. Results: The pressure fluctuation due to the opening and closing of the hinged door was very large when the moment of the hinged door opened and closed. Especially, at the moment when the door is closed, a pressure reversal phenomenon occurs in which the pressure in the isolation room is larger than the pressure in the anteroom. On the other hand, the pressure fluctuation due to the opening and closing of the sliding door appeared only when the door was closed, but the pressure reversal phenomenon not occurred at the moment when the sliding door was closed, unlike the hinged door. As the opening and closing speed of the hinged door increases, the air exchange volume is increased. However, as the opening and closing speed of the sliding door is decreased, the air exchange volume is increased. Implications: According to the results of this study, it can be concluded that the pressure fluctuation due to the opening and closing of the hinged door is greater than the pressure fluctuation due to the opening and closing of the sliding door. In addition, it can be confirmed that the pressure reversal phenomenon, which may cause to reduce the containment effect in negative pressure isolation room, is caused by the closing of the hinged door. Therefore, it is recommended to install a sliding door to maintain a stable differential pressure in the negative isolation room. Also, as the opening and closing speed of the hinged door is slower and the opening and closing speed of the sliding door is faster, the possibility of cross contamination of the room can be reduced. It is therefore necessary to establish standard operating procedures for negative isolation room for door opening and closing speeds.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.268-273
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• 1991

Missile and target closing velocity is used in the proportional navigation(PN) missile guidance loop. But it is difficult to estimate the closing velocity when passive seeker is used and only the Line-of-Sight(LOS) rate is available in the guidance loop. In this study, new closing velocity estimation method is developed. This method uses LOS rate measurement only and uses some characteristics of PN guidance law. The Lyapunov method is used to analyze the stability of the developed estimation method.

• 약학회지
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• 제47권5호
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• pp.271-275
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• 2003

Easy and efficient synthetic route of novel 4'-C methyl branched carbocyclic nucleosides is described. The installation of alkyl and aryl groups at 4'-position of carbocyclic nucleosides were successfully made via sequential [3,3]-sigmatropic rearrangement and ring-closing metathesis (RCM) starting from simple ketones such as acetol. Adenine and uracil were coupled via Pd(0) catalyzed reaction, followed by desilylation to give novel compounds 13 and 14, respectively.

• 한국농촌건축학회논문집
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• 제2권2호
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• pp.23-34
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• 2000

Many primary schools that have been an important role in the community at the same time local important facility not only local area but also all area in Korea have shown a situation for closing and into grating a school because of a social and political measure. The education policy for man power training and closing policy for small scale school not more than 100 students can't role in the rural development policy, coming farming and fishing villages. The reasons for thinking some application paradigm and closing schools have been important role in the point of education and culture parts. Of course, the application paradigm for closing school facility will get accomplished for a mood of local residents and a point of cultural deference, not keeping up unconditionally for closing a school. For accomplishing versatile purposes, initiative role of the organs of local education is very important. The organs of local education have an application paradigm that closing schools are the facilities for local organs of education will plan some specific facility to be matched for local special quality and connection quality of surrounding facility and environment. Before an application paradigm of closing school, it is very important that a fundamental factor for negligence the facility will be solved. Eventually, the organs of education have a plan for technical study of this paradigm and consider keeping and mending of closing facility, rent the facility for payment or not they want, and confer money problem not an unconditional scale.

• 대한수학회보
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• 제35권3호
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• pp.559-562
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• 1998

We prove the $C^r$ Closing Lemma for chain recurrence in compact surfaces.

• 한국자동차공학회논문집
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• 제6권2호
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• pp.67-79
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• 1998

Inthe study, a method to evaluate the door closing sound has been developed. Based on the factor analysis, various adjective pairs which describe meaning of the door impact sound have been differentiated. This approach, called Semantic difference(SD) method, was originally developed in linguistics research on order to compare diverse mother tongue. This paper introduces at first how the door sound os generated and transmitted. After that, a factor analysis which is a tool of SD method is implemented to door closing sound for 12 domestic and 1 foreign car models. During investigation, the examined models are categorized into small, medium and luxurious size automobiles. The adjective pairs which attritbute to the door quality have been factorized into three group : expensive/ smooth, powerful/ heavy, and modern/dull. It turns out that the first factor : expensive/ smooth plays the most important role in door closing sound quality.

• 소성∙가공
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• 제19권8호
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• pp.480-485
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• 2010

In this work, the closing behavior of cylindrical-shaped voids was experimentally investigated according to various parameters such as reduction ratio in height, initial void size and billet rotation during hot open die forging process. The reduction ratio in height, number of path, and billet rotation were chosen as key process parameters which influence the void closing behavior including the change of void shape and size. On the other hand, values of die overlapping and die width ratio were set to be constant. Void closing behavior was estimated by microscopic observation. Based on the observations, it was confirmed that application of billet rotation is more efficient to eliminate the void with less reduction ratio in height. The experimental results obtained from this study could be helpful to establish the optimum path schedule of open die forging process.