• Journal of the Korean Data and Information Science Society
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• 제26권3호
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• pp.631-638
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• 2015

본 연구는 대학정보공시 자료를 활용하여 2010~2013년까지 4년간의 패널자료를 구성하고 패널분석을 통해서 우리나라 4년제 대학의 등록금 및 장학금이 대학 휴학률에 미치는 영향을 국공립 대학과 사립 대학으로 나누어 파악했다. 전임교원 1인당 학생수, 취업률, 학생 1인당 교육비, 평균 등록금, 1인당 장학금 등을 고려해 3가지 모델로 연구하였다. 이 연구의 결과는 국공립 대학에서 등록금 및 순 등록금 (net tuition)이 낮을수록 대학 휴학률이 낮아지며, 1인당 교외 장학금이 높을수록 대학휴학률이 낮아졌으며, 사립 대학에서는 등록금이 낮을수록 대학 휴학률이 낮아졌으며, 1인당 장학금(교내+교외), 1 인당 교내장학금 및 교외장학금이 높을수록 대학 휴학률이 낮아지는 결과를 보였다.

• 한국항공운항학회지
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• 제18권4호
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• pp.67-72
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• 2010

In this study, performance analysis and design optimization is carried out for a multi-rate spring brake system, which is used in a cable ride to stop the arriving passengers in safe and comfortable manner. Mathematical model for the spring is developed toward the objective of minimizing the impact at the arrival while satisfying the constraint of limited distance at the stop. Matlab code is utilized to examine parameters affecting the performance of the brake system. The results are validated by a commercial software RecurDyn. Kriging meta model is used to reduce the computational cost of the analysis. Optimization is conducted by RecurDyn, from which the design parameters are determined that minimizes the impact at the stop.

• 보건교육건강증진학회지
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• 제25권3호
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• pp.111-124
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• 2008

Objectives: The purpose of this study was to suggest effective methods for not only preventing college students from being exposed to smoking but also helping them stop smoking, by examining and analysing a variety of factors related to their smoking behavior. Methods: To accomplish the purpose, this study was carried out using 1,553 valid questionnaires selected from 1,584 questionnaires completed and returned by 1,800 randomly chosen students of 2 colleges and 3 universities in Gyeongsangbuk-do Province and Daegu City during the period of April 3 through April 21, 2006. Results: It was turned out that while the total smoking rate of whole students was 52.4% in male students and 9.1% in female students, the smoking rate after their admission to the college was 27.1% in males and 1.5% in females. It was also shown that both the perceived susceptibility and barrier factors of Health Belief Model were statistically significant, and that the perceived seriousness factors were entirely significant in all other variables except the body seriousness. The perceived benefit factors were significant in only the variable that there would not be any improvement in academic performance even after stopping smoking. A relation between smoking and stop smoking program or smoking prevention program showed that the non-smoking rate was significantly high among the college students who participated in such programs while in middle school. When variables having a significant effect on smoking students after their admission were analysed, it was shown that the smoking rate was higher among males than females students, and that the more the number of smoking friends is and the more the number of students thinking that stop smoking would make it difficult to release stress and make friends is, the higher the smoking rate is among students. It is required, therefore, to encourage students to continuously participate in more smoking prevention programs from middle school, and to put an emphasis on a variety of smoking-related illnesses and advantages from non-smoking. Conclusions: Since the current smoking rate among college students is relatively high but most of the smoking students surveyed are ready to actually try to stop smoking, it will be possible to significantly reduce the smoking rate among college students if proper methods are suggested to eliminate barrier factors they face while participating in the stop smoking programs.

• The Korean Journal of Ceramics
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• 제4권3호
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• pp.193-198
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• 1998

This paper presents the effects of an initial braking velocity, a braking pressure, and the number of braking stop on the tribological behaviors for the three different C-C composites using an inertia dynamic-friction tester. The C-C composites were prepared through the processes of several cycles of pitch impregnation/carbonization with different friction surface texture such as continuous 8-harness satin fabric (ADD-1), chopped fiber (ADD-2) and chopped fiber (ADD-3) having higher fiber volume fraction on friction than ADD-2 by about 10%. ADD-1 exhibited a higher fraction coefficient (0.41~0.33) than those of ADD-2 and ADD-3 (0.32~0.26) under the various initial braking velocities and braking pressures. The fraction coefficients decreased with increasing the initial velocity and the braking pressures. Wear rate by the thickness change after every 25 stop indicated that ADD-2 and ADD-3 having 1.7~2.7 $\mu\textrm{m}$/stop/pair were much lower than that of ADD-1 showing 5.0~6.5 $\mu\textrm{m}$/stop/pair. All specimens showed a little bit lower wear rate during the middle stage than the initial and latter stages among 100 braking stops. ADD-1 showed higher friction coefficient and wear rate due to the active pull-out of the fibers, evidenced by thicker were film and wear debrises.

• 대한음성학회지:말소리
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• 제33_34호
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• pp.43-55
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• 1997

This study examined one of the hypotheses on the consonant reduction in Korean inferred from the Articulatory Phonology framework through phonetic experiments: Degree of consonant reduction depends on the height of the neighboring vowels--the lower the height of the neighboring vowel is, the higher the degree of reduction of stop closure period is. The results of this study, in general, turned out to support the hypothesis with some cases requiring other phonetic considerations, e.g., rate of some tongue tip movement in the case of dental lenis stop /t/ or the facts that bilabial lenis stop /p/ share its primary articulators, lips, with the neighboring vowel /u/ and that for bilabial closure, the upper lip lowers more for compensation of little movement of lower lip when its raising gets disturbed for some reasons.

• 한국가스학회지
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• 제17권2호
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• pp.70-77
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• 2013

본 연구는 화력발전소 최종과열기에서 고압터빈 사이 배관과 고압터빈을 지난 곳에 있는 체크밸브와 1차 재열기 사이 배관을 포함한 수증기 배관시스템에서 터빈의 급작스런 사고로 인해 터빈으로 들어가는 수증기를 차단할 때 발생하는 수증기 충격이 배관시스템에 미치는 영향을 분석하는 연구이다. 이를 위해서 수격현상 해석에 많이 사용하는 Flowmaster 소프트웨어로 배관시스템을 모델링하고 시간 변화에 따라 배관 내부의 압력, 질량유량률의 특성을 파악하였다. 이러한 특성으로부터 수증기 충격이 주로 영향을 미치는 곡관에서 수증기 충격에 의한 힘을 도출하였다. 본 연구를 통해서 수증기 충격은 주증기 차단 밸브 직전의 곡관과 체크밸브 이후에 바이패스 배관과 연결되는 곡관에서 수증기 충격에 의한 힘이 가장 크게 나타남을 밝혀냈다. 본 연구에서는 이렇게 도출한 힘의 기본 자료를 이용하여 차후 연구에서 화력발전소 수증기 배관시스템의 수증기 충격 시 곡관과 지지대의 안전성을 진단하는 토대를 구축하였다.

• 대한약리학회지
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• 제2권1호
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• pp.13-16
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• 1966

The action of serotonin (5-Hydroxytryptamine) on the excretory function of the kidney was investigated in the dog, utilizing the clearance method and the stop-flow technique. It was shown that serotonin, $10{\mu}g/kg/min$, i. v., exerts a marked antidiuretic effects and elicits a marked hemodynamic changes in the kidney: a highly significant decrease of the glomerular filtration rate and a tendency of decrement in the renal plasma flow. Little change in the systemic blood pressure was noted, and the participation of the antidiuretic hormone in the antidiuretic action was ruled out by adding vasopressin to the infusion fluid. The stop-flow analysis showed that there is no evidence of altered activity in the tubules by serotonin. It was thus concluded that serotonin elicits anti diuresis in the dog by decreasing glomerular filtration rate, which results from the constriction of Vas afferens in the glomeruli.

• 한국도로학회논문집
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• 제15권6호
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• pp.135-141
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• 2013

PURPOSES : The lack of details of design guideline for zig-zag shaped section approaching central bus stop leads an traffic accident proneness. So, this study analysed the geometric elements of central bus stop area in terms of vehicle dynamics and suggested design alternatives. METHODS : The study analysed a dynamic behaviour of bus moving in and out of zig-zag shaped section using Auto-Turn under scenarios. Based upon dynamic analysis, the study found out the width of overtaking lane is the most influential factor for a safe moving at zig-zag alignment. RESULTS : The width of overtaking lane at design speed of 40, 50, and 60 km/h respectively was suggested given taper ratio of 1 to 10 required for Bus Rapid Transit (BRT), and the lane width is not wider than 4.0m which possibly makes two vehicles using the same lane. Also, the width of overtaking lane which mitigates the taper ratio was suggested with the same restriction about the maximum lane width. CONCLUSIONS : The results of the study can be used to prepare a design guideline on zig-zag shaped alignment of central bus exclusive lanes. The more stable moving is expected by applying the design alternatives suggested, therefore the lower rate of traffic crashes at the vicinity of central bus stops.

• 말소리와 음성과학
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• 제1권3호
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• pp.39-48
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• 2009

Previous studies on the effects of speaking rate on voice onset time (VOT) of stops in English, French, Icelandic, and Thai indicate that speaking rate asymmetrically affects VOT values. That is, pre-voiced and long-lag stops vary due to the rate factor more than short-lag stops do. One suggested explanation for this asymmetry is that it is due to the necessity of maintaining phonetic contrasts among the stop categories. Since pre-voiced and long-lag stops represent the ends of the VOT scale, they encompass broad swathes of that range and consequently allow for large variations. On the other hand, the VOT variations of short-lag stops may result in overlap with the VOTs of long-lag stops. This study aimed to explore the effects of speaking rate on the VOTs of Korean stops and see whether Korean fortis and lenis stops are limited in the degrees of variation as a function of rates due to the existence of stops with larger VOT values, lenis and aspirated stops respectively. Conversely, aspirated stops were expected to show more variation since there are no other categories with longer VOTs. Fortis, lenis, and aspirated stops in /CVn/ words (C = bilabial or velar stop, V = /i/ or /a/) were examined in isolation, and at normal and fast rates in a carrier sentence. Speaking rates were controlled by alternating words or sentences on a computer screen at intervals of two seconds for the isolation- and normal-rate conditions and one second for the fast-rate condition. This study found that while the VOTs of fortis stops did not change significantly, those of lenis and aspirated stops showed considerable changes as a function of speaking rates. Also, overlap between lenis and aspirated stops occurred considerably at all speaking rates. These phenomena were interpreted to relate to the fact that VOT contrasts between lenis and aspirated stops in Korean are currently being collapsed. Large variations of lenis stops as a function of rates seem to occur due to a weak motivation to limit the degree of variations for the purpose of maintaining phonetic contrasts. The significant overlap between lenis and aspirated stops at all rates was interpreted to occur because the VOT merger between the two categories became considerably fixed. Also the percentage of correctly-classified VOTs by optimal-boundary values between lenis and aspirated stops turned out to be lower than in previously-studied languages. This was interpreted to be further evidence that VOTs are losing their role in contrasting the two stop categories in Korean.

• 복식
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• 제41권
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• pp.185-206
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• 1998

The purpose of this study was to improve productivity for maximum effects with the present equipments and staff. This study compared and analyzed the mea-sured time by using stop watch method and MTM, which was the new measuring method. The flow and results of this study were as follows: 1. This study investigated the theoretical background the efficiency for production management, and the way of productivity improvement through documentary research. 2. Setting up the standard flow on the experi-mental company production, making out a process chart and measuring the actual working hour. 3. The study measured the allowance time applying work sampling. 4. Each process of the movement analysis was filmed by video to use basic data. 5. MTM analysis was taken by choosing 10 processes from front bodice according to the basic movement of MTM. Through the results, this study exclude unneccesary movements and suggest a method for working ways. 6. Using the actual working hour measured by a stop watch calculated the pitch time and presumed the amount of daily productivity. 7. The result of the work sampling came out as 38% of allowance rate. It was 13% higher than the standard amount of woman's jacket allowance rate, which was 25%. The most influencing factor was work discussion. That was because there were commuication problem of the work way between the operator and leader. More adequate use of flow table and level passing table was needed. There were the problems that inappropriate places and sizes made the distance of movements longer and often needed more adjustment of works and surroundings. To prevent breakdowns equipments check ups were necessary before works. 8. The results of MTM analysis were as follow : the time was reduced 40% than the actual measured time by a stop watch. This was because the leveling of the operator was included in the real calculation. Also, leveling was included in MTM analysis and all the conditions were standarized. Therefore MTM method was a scientidic measuring way of establishing the standard time. The presented method of this study, suggested an ideal method eliminating unneccesary motions, and presented standardization of works. Improvement of working methods, work condition and simplifying motions in each 10 processes reduced the working time from total 656 seconds to 301 seconds. 9. The way and time of working was linked together in the MTM analysis methods. Thus data from MTM help suggest not only establishing standard time but also establishing stan-dard work. Plus it includes various ability for improvements of working ways. So it is an objective method which can be widely used in other work studies. 10. The function of a time study is to determine the amount of work produced with a given method. The work rate is used to establish the cost of labor. The wage of worker must be calculated per unit time which is deter-mined before the time study is made. This study tried to introduce the incentive rule for deciding wages according to the standard time by MTM method.