• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.593-596
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• 2008

Because of good performance of heat transfer characteristics, impinging jets are widely used in many industries for cooling or heating. And the present num erical studies attempt to show the effects of impinging jet. This paper considers the application of the turbulent models to impinging jet flow with pulsed inlet. It is assumed two-dimensional turbulent flows. The jet Reynolds num ber is set at 23,000 and the distance from the exit of the nozzle to the plate is 3 times larger than the diam eter of the nozzle. The influence of the Strouhal num ber(pulsation frequency) on Nusselt number at the impinging region is investigated. Strouhal numbers are ranged 0.0 to 0.5 and the forcing amplitudes are 1%,5%,9% of mean inlet velocity. In this study, the Nusselt number at the impinging region is sensitive to the pulsation frequency. Heat transfer coefficient strongly increase at Strouhal num ber of 0.4.

• Journal of Korean Society of Transportation
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• v.14 no.2
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• pp.59-88
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• 1996

This study has determined optimal type, and location of loop detector to measure accurately traffic condition influenced by traffic variation with real time. Optimal type of loop detector for through vehicle at stop bar was determined by confidences of occupancy period, and nonoccupancy period, and so appropriate detector type for application to real time traffic control system has been decided on special loop detector.

• Journal of Internet Computing and Services
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• v.7 no.1
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• pp.165-172
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• 2006

This paper describes which UPAN System Implementation using an NAN System as Ubiquitous Numbering and Address System. IT is based to UPTN and eNUM and also scribed by NAN of the ortho phonic korean alphabet. other case, in English. the UPAN system is integrated by two kind of numbering system, one is PSTN, another is domain name and address based IP. By this result we contributed personal ID and many kind of numbering of telecommunications services and all kind of personal ID and numbering system by the proper auto-raising registration. Now, we are confirmed this is key solution of ubiquitous networking and defined supra service structures.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.47-47
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• 2003

The presenilin 1 (PS1) or PS2 is an essential component of the ${\gamma}$-secretase complex, which mediates the intramembrane proteolysis of selected type-I membrane, including the ${\beta}$-amyloid precursor protein (APP) to yield A${\beta}$. Familial Alzheimer's disease (FAD)-associated mutations in presenilins give rise to an increased production of a highly amyloidogenic A${\beta}$42. In addition to their well-documented proteolytic function, the presenilins play a role in calcium signaling. We have previously reported that presenilin FAD mutations cause highly consistent alterations in intracellular calcium signaling pathways, which include deficits in capacitative calcium entry (CCE), the refilling mechanism for depleted internal calcium stores. However, molecular basis for the presenilin-mediated modulation of CCE remains to be elucidated. In the present study, whole-cell patch clamp method was used to identify a specific calcium-permeable ion channel current(s) that is responsible for the CCE deficits associated with FAD-linked PS1 mutants. Unexpectedly, both voltage-activated and conventional store depletion-activated calcium currents I(CRAC), were absent in HEK293 cells, which were stably transfected either with wild-type or FAD mutant (L286V, M146L, and delta E9) forms of PS1. Recently, magnesium-nucleotide-regulated metal cation current, or I(MagNum), has been described and appears to share many common properties with I(CRAC) including calcium permeability and inhibitor sensitivity (e.g. 2-APB). We have detected I(MagNum) in all 293 cells tested. Interestingly, FAD mutant 293 cells developed only about half of currents compared to PS1 wild type cells.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.3B
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• pp.138-143
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• 2005

This paper aims to optimize an access probe algorithm for the CDMA 2000 system. The incremental value of PWR_STEP increases as NUM_STEP as 1dBm±0.2 for access probe of the area with good receiving sensitivity when the mobile station transmits via access channel and does not receive any ACK message. However, for the area with weak receiving sensitivity, according to the algorithm of open-loop power control, the transmitting power amplifier becomes saturated and PWR_STEP incremental value keeps performing access probe to 0dBm±0.2. Therefore interference and battery consumption increases according to the transmission of the mobile station. We have optimized the access probe algorithm according to the receiving sensitivity. We transmit the incremental value of access probe power, with delaying as much RT slot value as indicated by IS-95C standard in case of good receiving sensitivity and with delaying RT+l slot value in case of weak receiving sensitivity. Simulation results showed that the proposed algorithm contributes to decrease of the interference and battery consumption according to the transmitting power of the mobile station and improves the call duration.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2003.12a
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• pp.35-41
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• 2003

반도체 제조라인의 유틸리티 분야에 국내 기술이 도입되고 이에 따른 관리시스템 구축의 중요성이 부각되고 있으며 유틸리티 시스템의 한 부분인 냉각 시스템의 효율성 증대에 관심을 보이고 있다. 본 연구에서 펌프의 효율 계산 프로그램을 NUMS(New Utility Management System)에 반영하고 현재 가동중인 시스템인 NUMS와 같은 조건 하에서 정상상태 유동해석을 통하여 각 구성 요소에서의 유량 및 압력을 제공할 수 있는 시스템을 구현 하였고 NUMS와 압력비교를 하였다. 또한 효율성 증대를 위해 적절한 By-pass 밸브의 개도와 펌프 1대를 줄일 수 있는 결과를 얻었다. 이 결과는 차후 운전 및 관리의 효율성 증대와 에너지 절감을 위한 자료로 이용하고자 한다.

• Phonetics and Speech Sciences
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• v.13 no.1
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• pp.45-51
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• 2021

End-to-end (E2E) automatic speech recognition (ASR) has achieved promising performance gains with the introduced self-attention network, Transformer. However, due to training time and the number of hyperparameters, finding the optimal hyperparameter set is computationally expensive. This paper investigates the impact of hyperparameters in the Transformer network to answer two questions: which hyperparameter plays a critical role in the task performance and training speed. The Transformer network for training has two encoder and decoder networks combined with Connectionist Temporal Classification (CTC). We have trained the model with Wall Street Journal (WSJ) SI-284 and tested on devl93 and eval92. Seventeen hyperparameters were selected from the ESPnet training configuration, and varying ranges of values were used for experiments. The result shows that "num blocks" and "linear units" hyperparameters in the encoder and decoder networks reduce Word Error Rate (WER) significantly. However, performance gain is more prominent when they are altered in the encoder network. Training duration also linearly increased as "num blocks" and "linear units" hyperparameters' values grow. Based on the experimental results, we collected the optimal values from each hyperparameter and reduced the WER up to 2.9/1.9 from dev93 and eval93 respectively.

• Journal of the korean veterinary medical association
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• v.15 no.4
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• pp.195-202
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• 1979

Samples of blood from 264 health adult Holstein cows were examined to determine the variation of blood composition during pregnancy and early lactation. The animals were selected from herds in Jeonnam area. The results were summarized as below: 1. The num

• Korean Journal of Plant Tissue Culture
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• v.25 no.5
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• pp.301-304
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• 1998

Effects of genotype and culture medium on plant regeneration from cotyledon segments of red pepper(Capsicum annuum L.) was investigated. Among combinations of IAA(0.25 and 0.50 mg/L) and zeatin(2.0 and 4.0 mg/L) added to MS medium, combination of 2.0 mg/L zeatin and 0.25 mg/L IAA was shown to be the best for shoot differentiation from cotyledon segments. Shoot regeneration from cotyledon explants took 9 to 25days, depending on genotypes and culture media. Early shooting was observed in Yeongyangjaelae, Putgochw, Karkovskij-A-35, Gris I-A-1 on MS medium containing 2.0 mg/L zeatin and 0.25 IAA mg/L. Percent of explants producing shoots, as also influenced by genotypes and culture media, were over 90% for 621, Yeongyangjaelae, Putgochw, Nikko jacksacgmulgochw, Ch-6-Num-216, and Kajenskij-A-35 when cultured on MS medum supplemented with 2.0 mg/L zeatin and 0.25 mg/L IAA and for Fresno chile, PI 169126, Kajenskij-A-35, jacksacgmulgochw, and PI 297438 on MS medium including 2.0 mg/L BA and 1.0 mg/L IAA.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.91.4-91
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• 2002

Today, Internal offers WWW(World Wide Web), remote control, file transfer and e-mail service. Among the services, WWW takes large portion because of convenient GUI, easy information search and unlimited information registration. WWW service gives the comfort in life such as goods purchase, information search, real-time news, internet TV and medical diagnosis. Remote Monitoring Server(RMS) Ssystem that uses internet and WWW is constructed for chip mounter. Hardware base consists of RMS, chip mounter and C/S(Customer Service) service. Software includes DBMS and various modules in server home page. Web browser provide product num her, bad product number, troubl...