• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.95-96
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• 2014

In this study, the nano-particle emitted from Gasoline Direct Injection(GDI) vehicles was measured using the Engine Exhaust Particle Sizer(EEPS) on a chassis dynamometer. In addition, driving mode were divided into cold start mode(CVS-75, NEDC) and hot start mode(NIER-6, NIER-9) to evaluated the characteristics in the various operating conditions. The Particle Number(PN) concentration was analyzed for various driving patterns, i.e., acceleration, deceleration, idling, cruising and the phases of mode. In a result, Total concentration of PN for size was concentrated from 50 to 100 nm and acceleration represents the highest concentration among the driving pattern. It is believed that the increases quantity of fuel, and mixture will be richer than other patterns.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.425-428
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• 2006

A semi-solid forming technology has some advantages compared with conventional forming processes such as die casting, squeeze casting and hot/cold forging. In this study, the numerical analysis of semi-solid filling has been studied with solid fraction fs = 30% of A356 aluminum alloys. The finite difference program of two-phase flow model of Navier Stokes' equation coupled with heat transfer and solidification has been developed to predict a filling pattern, liquid segregation and temperature distribution of semi-solid metals. It gives die filling patterns and final solidification area. It can predict mechanical properties of semi-solid forming processes.

• 대한기계학회논문집A
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• 제28권1호
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• pp.79-84
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• 2004

A light-guide is one of several important components of backlight unit in TFT-LCD. The manufacturing technology and optical system design of the light guide is very sensitive to quality and cost of the TFT-LCD module. In the present study a new manufacturing method which is called as direct surface forming(DSF) has been tested under various conditions. DSF is very similar to the well-known hot embossing except for partial contact between mold and substrate. The final V-groove pattern shows different shapes depend on the temperature of mold surface, contact time of mold and depth of V-groove.

• 반도체디스플레이기술학회지
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• 제2권4호
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• pp.37-40
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• 2003

반도체 장비의 기능성과 신뢰성을 높이기 위하여 부품의 제조기술은 점차 마이크로 머신 기술을 요구하고 있다. 마이크로머신 기술 중 hot junction이 위치하는 멤브레인 구조는 각종 센서와 히터의 미세부품에서 가장 이용도가 큰 구조이다. 실험에서는 마이크로머신의 기본 구조인 멤브레인 형태를 만들기 위해 KOH 용액과 TMAH 용액으로 단결정 실리콘을 이방성 습식식각 하였다. 실험결과, 식각액의 온도와 농도, 마스크 패턴과 웨이퍼의 결정성의 일치 등을 고려해야 하며, 식각 속도는 KOH 농도 및 온도에 따라 크게 변함을 알 수 있었다. KOH 용액은 30 wt% 80~$90^{\circ}C$ 온도 범위에서 가장 좋은 특성을 나타냈다. 한편, TMAH용액이 실리콘을 식각하는 용액으로 관심을 끄는 것은 단결정에서 상대적으로 $SiO_2$ 박막을 마스크로 사용할 수 있을 뿐 아니라 $SiO_2$ 박막을 마스크로 사용할 수 있을 뿐 아니라 다른 식각액보다 찌꺼기가 적다는 장점 때문이다. 그러나, 다른 용액에 비해 가격이 고가이며 식각 속도가 낮다는 것이 실용적인 측면에서 큰 단점이다. 실험결과를 종합적으로 고려할 때 KOH 용액 농도 30wt%와 온도 $90^{\circ}C$가 마이크로머신 기술에 의한 멤브레인 구조 제작에서 적합한 공정조건이라고 할 수 있다.

• 디지털융복합연구
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• 제14권6호
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• pp.457-466
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• 2016

본 연구는 친환경 병원을 실현하는데 도움이 되는 연구로서 병원의 전력사용량에 미치는 기상요인의 영향을 실증적으로 검증하고자 한다. 이를 위해 2009년부터 2013년까지 일별 자료를 기준으로 2개 종합병원을 대상으로 기상조건에 따른 전력 사용 패턴과 그 영향을 분석하였다. 분석결과, 병원 건물의 전력사용량에 가장 큰 영향을 미치는 기상요인은 '기온'으로 나타났고, 병원의 규모에 상관없이 유의한 영향을 미치는 것으로 나타났다. 그러나 병원의 전력소비 패턴은 병원의 규모에 따라 차이가 있었다. 큰 규모의 병원에서는 선형의 전력소비 패턴이 나타났지만 작은 규모의 병원에서는 2차 곡선의 비선형 패턴으로 나타났다. 더운 여름과 추운 겨울에 병원 건물의 전력사용량이 증가하는 전형적인 전력소비 패턴을 보이는 것으로 나타났다. 본 연구결과는 에너지 절약과 친환경 건물 개선을 위하여, 병원 건물의 기능적 특수성뿐만 아니라 기상요소를 반드시 고려해야 한다는 것을 시사한다.

• 대한한방부인과학회지
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• 제27권3호
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• pp.66-78
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• 2014

Objectives: The purpose of this study is to investigate the relationship between vasomotor symptoms with upper-lower body temperature differences, and to identify Kidney Deficiency pattern (腎虛證) in menopausal women. Methods: 51 women who visited Kangnam Kyung-Hee Oriental Hospital from July to December, 2013 were analyzed. The experimental group consisted of 30 patients reported with vasomotor symptoms (Vasomotor symptom group, VG), while the control group consisted of 21 patients without vasomotor symptoms (Control group, CG). According to their chief complaints, VG was further divided into VHG (vasomotor-hot flash group) and VCG (vasomotor-cold hypersensitivity group). The temperature differences between upper and lower body part (CV17-CV4), proximal and distal extremity part (LU4-HT8, ST32-LR3) were checked. All patients reported other complaints such as headache, sweating, anxiety, dyspepsia, leukorrhea, which belong to Kidney Yang Deficiency pattern (腎陽虛證) or Kidney Yin Deficiency pattern (腎陰虛證). The relationship between vasomotor symptom and repetition rate of additional complaints were analyzed. Results: Statistical analysis showed that lower abdomen temperature of experimental group was lower than the control group. Temperature differences of upper and lower body (CV17-CV4) was significantly larger in vasomotor symptom group. VHG had more symptoms of sweating, chest discomfort, constipation, which belong to Kidney Yang Deficiency pattern group. VCG had more symptoms of leukorrhea, diarrhea, and dyspepsia, which belong to Kidney Yin Deficiency pattern group. Conclusions: Climacteric women who suffered from vasomotor symptoms showed lower temperature tendency in [CV4], larger temperature differences in [CV17-CV4] compared to the control group. Among them, VHG showed more symptoms of Kidney Yin Deficiency pattern, whereas VCG showed more symptoms of Kidney Yang Deficiency pattern.

• Asian-Australasian Journal of Animal Sciences
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• 제16권7호
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• pp.952-961
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• 2003

In the first part of the study, rates of estrus occurrence and success of A.I. service in the Thai-native and Friesian crossbred, and purebred Friesian cows fed in the National Dairy Training and Applied Research Institute in Chiang Mai, Thailand were traced monthly throughout a year. An electric fan and a water sprinkler cooled the stall for the purebred cows during the hot season (March-September). Both rates in pure Friesians were at their highest in the cold-dry season (October- February), but they decreased steadily during the hot-dry season (March-May) and were at their lowest in the hot-wet season (June-September). Seasonal change of a similar pattern was observed in the incidence of estrus, but not in the success rate of insemination in the crossbred cows. By the use of reproductive data, compiled in the same institute, on the 75 % cross- and purebred Friesian cows, and climatological data in Chiang Mai district, effects of ambient temperature and humidity on the reproductive traits of cows were examined by regression analysis in the second half of the study. Significant relationships in the crossbred, expressed by positive-linear and parabola regressions, were found between reproductive parameters such as days to the first estrus (DTFE), A.I. service (DTFAI), and conception, the number of A.I. services required for conception and some climatic factors. However, regarding this, no consistent or intelligible results were obtained in purebred cows, perhaps because electric fans and water sprinklers were used for this breed in the hot season. Among climatic factors examined, the minimum temperature (MINT) in early lactation affected reproductive activity most conspicuously. As the temperature during one or two months prior to the first estrus and A.I. service rose, DTFE and DTFAI steadily became longer, although, when MINT depleted below $17-18^{\circ}C$, the reproductive interval tended to be prolonged again on some occasions. The maximum temperature also affected DTFE and DTFAI, but only in limited conditions. The effect of humidity was not clear, although the inverse relationship between DTFE and minimum humidity during 2 months before the first estrus in the crossbred seemed to be significant. Failure to detect any definite effect of climate on the reproductive traits of pure Friesians seemed to indicate that forced ventilation by electric fans and water sprinklers were effective enough to protect the reproductive ability of this breed from the adverse effects of a hot climate.

• The Journal of Korean Physical Therapy
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• 제13권1호
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• pp.175-188
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• 2001

The purpose of this study was to investigate the effect of the cold air application for release of inflamation and pain in patient with acute rheumatoid arthritis who had taken medication(NSAIDs, DMARDs, corticosteroids). The participants had knee joint pain and ESR score over the 30. They were randomly assigned to three groups with each 15. Control group(group I ) were applied cold air and medication, experimental group II were applied hot pack and medication. and experimental group III were applied only medication. They were evaluated from April 1, 2000 to september 1,2000 ,and it was examined by ESR and VAS(visual analoge scale) in Lee Bang Hoon rehabilitation medicine clinic in Jeju Korea. The result of this study were as follow: 1. It was found that group 1, group II and group III had the statistically significant reduction of the ESR score according to treatment time(p<.05). 2. There were not statistically significant differences in ESR change pattern of each group according to treatment time(p>.05). 3. There were not statistically significant differences in the change of ESR according to treatment time between group I and group II , group I and group III , and group II and group III (p<.05). 4. It was found that group I . group II and group III had the statistically significant reduction of the VAS(Visual Analoge Scale) score according to treatment time(p<.05). 5. There were statistically significant differences in VAS score according to treatment time between control group(group I ) and experimental groups(group II and group III)(p<.05), but there were not stsiistically significant differences between experimental groups(p>.05).

• 한국정보처리학회논문지
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• 제3권7호
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• pp.1669-1679
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• 1996

In this paper, we address the problem of how to replace huffers in multimedia database systems with time-varying skewed data access. The access pattern in the multimedia database system to support audio-on-demand and video-on-demand services is generally skewed with a few popular objects. In addition the access pattem of the skewed objects has a time-varying property. In such situations, our analysis indicates that conventional LRU(least Recently Used) and LFU(Least Frequently Used) schemes for buffer replacement algorithm(ABRN:Adaptive Buffer Replacement using Neural suited. We propose a new buffer replacement algorithm(ABRN:Adaptive Buffer Replacement using Neural Networks)using a neural network for multimedia database systems with time-varying skewed data access. The major role of our neural network classifies multimedia objects into two classes:a hot set frequently accessed with great popularity and a cold set randomly accessed with low populsrity. For the classification, the inter-arrival time values of sample objects are employed to train the neural network.Our algorithm partitions buffers into two regions to combine the best roperties of LRU and LFU.One region, which contains the 핫셋 objects, is managed by LFU replacement and the other region , which contains the cold set objects , is managed by LRUreplacement.We performed simulation experiments in an actual environment with time-varying skewed data accsee to compare our algorithm to LRU, LFU, and LRU-k which is a variation of LRU. Simulation resuults indicate that our proposed algorthm provides better performance as compared to the other algorithms. Good performance of the neural network-based replacement scheme means that this new approach can be also suited as an alternative to the existing page replacement and prefetching algorithms in virtual memory systems.

• 설비공학논문집
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• 제26권11호
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• pp.522-528
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• 2014

This experimental study measured and analyzed the heat transfer and pressure drop performance of brazed plate heat exchangers. Heat exchangers with different plate numbers of 10, 20, 30, and 40 were used for measurement, and their plate pattern was identical. The experiment was performed with distilled water, by changing the hot-side flow rate, with the cold-side flow rate fixed. The experimental results were compared with the calculated values by correlations based on gasketed plate heat exchangers, and showed that the heat transfer performance and pressure drop of brazed plated heat exchangers were higher than those of gasketed plate heat exchangers. From the variation of the friction factor, it could be inferred that in the flow channels of brazed plate heat exchangers, turbulent flow occurred at Reynolds numbers higher than 500. A new correlation to predict the Nusselt number was developed, and its absolute average deviation was 2.62%, compared with the values from the experimental data.