• 한국태양에너지학회 논문집
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• 제25권1호
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• pp.45-55
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• 2005

In the summer, the irradiated solar heat gain through the roof has an effect on the thermal environment of the top floor units of apartment houses. This paper investigated the differences of the indoor air temperature, globe temperature and thermal comfort index between the top floor unit and the middle floor unit by measuring them at the sample units on the condition that all the openings of the units are opened. The purpose of this paper is to provide quantitative data about the irradiated solar heat gain during the summertime through the roof of an apartment house and these data to be the source to reevaluate the appropriate roof insulation efficiency. From this study, we obtained three brief results as follows. Indoor air temperature difference between the two sample units shifts a day. Indoor air temperature at the top floor unit is $0{\sim}1.8^{\circ}C$ higher than that of the middle floor unit from 12:00 p.m. to 12:00 a.m. and $0{\sim}2.8^{\circ}C$ lower from 12:00 a.m. to 12:00 p.m. The evaluation of the indoor thermal comfort index and the globe temperature shows similar results as the indoor air temperature measuring. Results of this experiment verified the actual existence of indoor air temperature difference between the top floor unit and the middle one and this difference comes from the heat storage of the roof.

• 한국재료학회지
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• 제2권4호
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• pp.279-284
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• 1992

고분해능 전자에너지손실 및 자외선광전자 분광법을 사용하여 단결정 NbC(111)면의 산소횹착을 연구하였다. NbC(111) 표면에는 산소가 원자 및 분자상태로 흡착되었다. 산소원자는 3-fold hollow site에 흡착되며 진동수는 548c$m^{-1}$이었다. 산소분자의 신축진동수는 968c$m^{-1}$로서 기체상태인 산소분자의 진동수보다 크게 낮았으며, 산소분자의 흡착으로 일함수가 증가하였다. 이는 NbC(111) 기판으로부터 산소분자의 2p${pi}_g$ 궤도로 전자가 이동하였음을 보여주는 증거이다.

• 한국인터넷방송통신학회논문지
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• 제20권1호
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• pp.219-223
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• 2020

딥 러닝 기반 객체 탐지 및 영상처리 분야에서 모델의 인식률과 정확도를 보장하기 위해 다량의 데이터 확보는 필수적이다. 본 논문에서는 학습데이터가 적은 경우에도 인공지능 모델의 높은 성능을 도출하기 위해 전이학습 기반 객체탐지 알고리즘을 제안한다. 본 논문에서는 객체탐지를 위해 사전 학습된 Resnet-50 네트워크와 YOLO(You Only Look Once) 네트워크를 결합한 전이학습 네트워크를 구성하였다. 구성된 전이학습 네트워크는 Leeds Sports Pose 데이터셋의 일부를 활용하여 이미지에서 가장 넓은 영역을 차지하고 있는 사람을 탐지하는 네트워크로 학습을 진행하였다. 실험결과는 탐지율 84%, 탐지 정확도 97%를 기록하였다.

• Environmental Analysis Health and Toxicology
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• 제16권4호
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• pp.223-226
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• 2001

Acetanilide is a High Production Volume Chemical, which is produced about 2,300 tons/year in Korea as of 1998 survey. Most is used as an intermediate for synthesis of pharmaceuticals and dyes. The chemical is one of seven chemicals, which are under the frame of OECD SIDS program sponsored by National Institute of Environmental Research of Korea. Regarding the information on the environmental fate. bioconcentration is one of important factor to estimate the environmental tranfer. However, measurement of bioconcentration needs high expense and time. For this reason, OECD recommends to use BCFWIN model to estimate bioconcentration of organic chemicals, BCFWIN estimates the bioconcentration factor (BCF) of an organic compound using the log octanol-water partition coefficient (Kow) of the compound. Structures are entered into BCFWIN through SMITES (Simplified Molecular Input Line Entry System) notations. The BCFWIN method classifies a compound as either ionic or non-ionic. ionic compounds include carboxylic acids, sulfonic acids and salts of sulfonic acids, and charged nitrogen compounds (nitrogen with a + 5 valence such as quaternary ammonium compounds). All other compounds are classified as non-ionic. In this study, bioaccumulation of acetanilide was estimated using BCFWIN model based on SMIIES notation, chemical name data and partition coefficient as one of environmental fate/distribution of the chemical elements.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2007년도 추계 종합학술대회 논문집
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• pp.60-64
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• 2007

VoIP, 영상회의, DMB, IPTV 등과 같은 멀티미디어 서비스의 활용이 급증하여 네트워크 트래픽이 증가되므로 흐름제어에 관한 실시간 트래픽 메커니즘이 요구되고 있다. 이에 따라 실시간 멀티미디어 데이터를 전송하기 위해 주기적으로 피드백되는 RTP/RTCP 패킷을 통해 수신측의 패킷 손실률과 패킷 지연시간으로 측정되는 네트워크 상태정보를 이용하여 전송률을 조절할 수 있다. 본 연구에서는 멀티캐스트에 효율적인 흐름제어와 RTCP를 기반으로 피드백 전송지연의 오차율을 줄이고, 네트워크의 실시간 트래픽에 대한 동적 변화에 적응할 수 있는 기법을 제안한다. 본 연구의 시뮬레이션 결과, 네트워크 상태에 적응적으로 전송률을 조절하며 대역폭의 최대 활용과 패킷 손실의 최소화를 이룰 수 있다.

• 대한기계학회논문집A
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• 제20권11호
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• pp.3538-3548
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• 1996

In this study, as a part of basic study for developing the simulation program for the assemssment of reliability of electronic EMC packaging which covers from EMC mixing step to thermal analysis, comparison between a measured and predicted values of material properties of EMC and finitde element analysis of thermal stress are performed. For the experimental testing specimens of fifty, sixty hive and eighty percent filler($13\mu m$, spherical silica) weight fraction are fabricated using tranfer molding. Coefficient of thermal expansion, elastic modulus and thermla conductivity are measured using these specimens and then these measured values are compared with the predicted values by various equations ( such as dilute suspension method. self consistent method, generalized self consistent method, Hashin-Shtrikman's bounds. Shapery's bounds, Nielsen's method and others). Measured values are distributed within the upper and lower bounds of equations. Measured elastic modulus and coefficient of thermal expansion approaches closely the perdicted values with self consisten mehtod and upper bound of Shaperys equation respectively. However small differences of thermal conductivity between the different filler volume fraction are obserbed. FEM analysis indicates that firstly stress is concentrated at the corner section of EMC and secondly EMC with eighty percent filler weight fraction shows less thermal stress when package is cooling down and relatively high thermal stress when package is heating up.

• 의료법학
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• 제14권2호
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• pp.281-313
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• 2013

A physician has to do his best for the better treatment of his patiensts. But, if a physician cannot remedy his patients because of the lack of hospital facilities, the lack of medical knowledge and etc., the physician must transfer his patients to another suitable hospital immediately. This is called the duty of interhospital transfer of patients. The necessity of interhospital transfer of patients is primarily ocurred in emergency medical care situations. The Supreme Court Decision 2010DO7070 delivered on April 29, 2010 is one of the important decisions related to the duty of interhospital transfer of patients. The Supreme Court ruled that there were the physician's medical malpractice and the causation between the physician's medical malpractice and the death of patient, as the physician has left the patient without due observations for 1 hour and 30 minutes after the caesarean operation inspite of mass bleeding during the operation, and has transferred the patient to another suitable hospital later. And the Supreme Court ruled that the transferring physician has to explain the situation of the patient in detail to the physician being transferred. I agree with the Supreme Court Decision. As decided by the Supreme Court, physicians will treat their patients more carefully and in case of necessity for transfer, physicians will transfer their patients with more caustion. However, the study for this issue should be continued hereafter because concrete standards are not given to lawers and physicians just by the Supreme Court Decisions itself.

• 한국유체기계학회 논문집
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• 제8권4호
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• pp.27-38
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• 2005

The present study investigated the effect of relative position of the blade on blade surface heat transfer. The experiments were conducted in a low speed wind tunnel with a stationary annular turbine cascade. The test section has a single turbine stage composed of sixteen guide vanes and blades. The chord length of the blade is 150 mm and the mean tip clearance of the blade is $2.5\%$ of the blade chord. The Reynolds number based on blade inlet velocity and chord length is $1.5{\times}105$ and mean turbulence intensity is about $3\%$. To investigate the effect of relative position of blade, the blade at six different positions in a pitch was examined. For the detailed mass transfer measurements, a naphthalene sublimation technique was used. In general, complex heat transfer characteristics are observed on the blade surface due to various flow characteristics, such as a laminar flow separation, relaminarization, flow acceleration, transition to turbulence and tip leakage vortices. The results show that the blade relative position affects those heat transfer characteristics because the distributions of incoming flow velocity and turbulence intensity are changed. Especially, the heat transfer pattern on the near-tip region is significantly affected by the relative position of the blade because the effect of tip leakage vortex is strongly dependent on the blade position. On the pressure side, the effect of blade position is not so significant as on the suction side surface although the position and the size of the separation bubble are changed.

• 한국가축번식학회지
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• 제17권1호
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• pp.57-68
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• 1993

This stduy was carried out to find a reliable method for the production of in vitro fertilized embryos having more excellent development capacity and freezability in the rabbit and cattle. The greatest number of rabbit oocytes was recovered 6hrs after HCG injection(P<0.05). The maturation rate in vitro was slightly higher in the oocytes(6-h-oocytes) from 6h than those (8-h-oocytes)from 8 hrs after HCG injection and the beneficial effect of FSH during oocyte maturation was significantly great in the oocytes from large follicles. The cleavage rate into 2-to-6-cell stage was not differ between the 6-h-oocytes and 8h-oocytes, but the cleavage of these oocytes was greatly promoted by FSH addition to maturation medium and the cleavge of 8-h-oocytes matured without FSH was significantly low. The embryo development into 16-cell to morula was not promoted by the co-culture with rabbit oviduct epithelial cells. The freezability by embryo stages was ovidusly high at 4-cell and morula stage in 6-h-oocytes and the viability of 16-cell embryos from 8h-oocytes was similar to that of morula stage. The implantation sites after surgical tranfer of fresh rabbit embryos were not implanted. In bovine experiment, the in vitro development into 16-cell and morula after in vitro maturation and fertilization in the follicular oocytes was slightly improved by the co-culture with granulosa cells compared to that with oviduct epithelial cells and the frozen-thawed viability rate of these embryos ranged from 14 to 40%. The excellent fresh embryos were transferred nonsurgically to 6 recipients, but were not pregnant.

• Clinical and Experimental Reproductive Medicine
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• 제26권3호
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• pp.447-456
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• 1999

Objective: The purpose of this study was to evaluate outcome of intracytoplasmic sperm injection (ICSI) using epididymal and testicular sperm in patients with azoospermia. Methods: From March, 1993 to May, 1999, a retrospective clinical analysis was done of a total of 140 cycles in 112 patients who underwent ICSI. Subjects were divided into three groups: ejaculated-ICSI group included 42 cycles in 34 patients with ejaculated sperm who underwent ICSI due to severe oligospermia and past history of failed or poor fertilization in the previous in vitro fertilization and embryo tranfer (IVF-ET) cycles, microsurgical epididymal sperm aspiration and intracytoplasmic sperm injection (MESA-ICSI) group included 50 cycles in 42 patients with congenital absence of the vas deferens (CAVD) or unreconstructable obstructive azoospermia and testicular sperm extraction and intracytoplasmic sperm injection (TESE-ICSI) group included 48 cycles in 36 patients with no spermatozoa which can be retrieved from epididymis or non-obstructive azoospermia. Results: Normal two-pronuclear fertilization rates were similar in three groups: 64.4% for ejaculated-ICSI group, 59.4% for MESA-ICSI group and 60.4% for TESE-ICSI group. The pregnancy rates were 26.2%, 26.0% and 25.0% respectively. There were no significant differences in the fertilization, cleavage, and clinical pregnancy rates among ICSI cycles using ejaculated, epididymal and testicular sperm. Conclusion: Epididymal and testicular sperm obtained in azoospermic patients can fertilize oocyte successfully and may lead to be similar fertilization rates and clinical pregnancy rates to ejaculated sperm.