• 한국산학기술학회논문지
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• 제14권3호
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• pp.1266-1273
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• 2013

본 연구에서는 double rocker sole을 채용한 기능성(complex function double rocker sole; CDR) 신발과 negative-heel rocker sole(NR)을 채용한 신발의 보행 중 에너지 소비량을 비교하여 보행시 에너지 사용을 증가시킬 수 있는 기능성 신발에 대한 기초자료를 제공하고자 하였다. 이를 위해 2011년 3~8월까지 40~50대 중년여성 11명을 대상으로 inbody 4.0 (Biospace, Korea)로 체성분 검사와 Vmax ST(SensorMedics, USA)로 운동부하 심폐기능 검사를 실시한 후, 분당 보행에너지 소비량(walking energy cost per time; WECt)과 심박수 운동강도(Heart rate intensity; HRi)를 산출하였다. 연구 결과, CDR신발은 NR신발에 비하여 심박수 운동강도의 통계적 유의차 없이 분당 보행에너지 소비량과 총 칼로리 소비량이 높게 나타나, CDR신발은 동일한 운동 조건 속에서 자각적 운동강도를 증가시키지 않고 운동량을 증가시킬 수 있으므로 에너지소모량을 높이고자 하는 사람에게 적합할 것으로 생각된다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권1호
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• pp.24-29
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• 2000

We propose a simple method to control the crystallization depth of amorphous silicon (a-Si) deposited by PECVD or LPCVD during the excimer laser annealing (ELA). Employing the new method, we have formed poly-Si/a-Si double film and fabricated a new poly-Si TFT with vertical a-Si offsets between the poly-Si channel and the source/drain of TFT without any additional photo-lithography process. The maximum leakage current of the new poly-Si TFT decreased about 80% due to the highly resistive vertical a-Si offsets which reduce the peak electric field in drain depletion region and suppress electron-hole pair generation. In ON state, current flows spreading down through broad a-Si cross-section in the vertical a-Si offsets and the current density in the drain depletion region where large electric field is applied is reduced. The stability of poly-Si TFT has been improved noticeably by suppressing trap state generation in drain region which is caused by high current density and large electric field. For example, ON current of the new TFT decreased only 7% at a stress condition where ON current of conventional TFT decreased 89%.

• 연구논문집
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• 통권29호
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• pp.111-121
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• 1999

고속 Rapier loom에서 경사와 위사의 조직을 완성하여 직물을 제직하는 위입과 바듸침 기구는 캠구동 방식으로 동일축선 상에 4개의 캠이 설치되어 있다. 이들 캠들은 2개씩 한쌍을 이루면서 서로 공액운동을 수행하고 있으므로 정확한 설계에 의한 동기화운동이 필수적이다. 따라서 본 연구는 전체 거동의 파악을 위한 시스템의 정확한 해석과 컴퓨터 시뮬레이션을 통한 Rapier loom의 고속화를 목적으로, 위입과 바듸침기구의 곡선선정 및 캠의 회전에 따라 정확한 운동을 유도할 수 있도록 2가지 운동의 연관성은 물론 동시에 화면상에 구현할 수 있는 4개의 캠기구에 대한 시뮬레이션 프로그램을 개발하는 것이다.

• 대한전자공학회논문지
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• 제26권2호
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• pp.10-17
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• 1989

Reed-Solomon(RS) 부호의 복호에서 오류위치다항식을 구하기 위한 알고리듬 중 Peterson에 의해 제안되고 Gorenstein과 Zierler가 개선한 알고리듬은 오류정정능력 t가 비교적 작을 경우 BerlekampMassey의 반복 알고리듬, Euclid 알고리듬을 이용한 복호, 변환영역에서의 복호보다 오류위치다항식의 계산이 간단하고 장치화에 이점이 있다. 본 논문에서는 Peterson-Gorenstein-Zieler의 알고리듬 RS부호의 부호화와 복호과정을 체계적으로 연구, 분석하고 실제로 통신 시스템에 응용할 수 있도록 유한체 GF($2^5$)의 심볼로 이루어지는 2중 오류정정(31,27)RS 부호의 부호기와 복호기를 설계하여 TTL IC로 장치화 하였다.

• 전자공학회논문지C
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• 제35C권11호
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• pp.57-62
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• 1998

본 논문에서는 넓은 입력 전압 범위에 걸쳐 좋은 선형성을 보여주는 가변 트랜스컨덕터를 제안한다. 제안된 트랜스컨덕터는 선형 영역에서 동작하는 입력 MOS 트랜지스터를 사용하여 회로의 구성이 간단하고 좋은 가변성을 갖고 6.8V/sub p-p/의 넓은 입력범위를 갖는다. 또한 소오스-결합 차동쌍을 이용하여 실질적인 차동입력을 제공하고 정과 부의 트랜스컨덕턴스 값을 제공한다. 제안된 회로는 1.2㎛ single poly double metal n-well CMOS 공정을 사용하여 제작되었다. 제안된 회로의 THD 특성은 V/sub DD/=-V/sub ss/=5V, I/sub B/=20, 40μA이고 입력 신호 주파수가 1KHz일 때 6V/sub p-p/의 차동 입력전압에 대해 1% 미만임을 보여준다.

• 한국태양에너지학회 논문집
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• 제27권4호
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• pp.19-26
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• 2007

This paper concerns the study of absorption refrigeration and heat pump cycle to use sewage. Simulation analysis on the double-effect absorption refrigeration cycle with parallel and two-stage heat pump cycle has been performed. The working fluid is Lithium Bromide and water solution. The absorption refrigeration cycle use sewage as a cooling water for the absorber and condenser, and absorption refrigeration cycle does that as a chilled water for the evaporator of the first stage cycle. And the two-stage cycle consists of coupling double-effect with parallel and single effect cycle so that the first stage absorber and condenser produces heating water to evaporate refrigerant in the evaporator of the second stage. The effects of operating variables such as a absorber temperature on the coefficient of performance have been studied for absorption refrigeration and heat pump cycle.

• ETRI Journal
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• 제33권3호
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• pp.344-354
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• 2011

In this paper, a model is introduced named double relation chains (DRC) based on ordered sets. It is proved that using DRC and special relationships among the members of an alphabet, vectors of this alphabet can be stored and searched in a tree. This idea is general; however, one special application of DRC is the longest prefix matching (LPM) problem in an IP network. Applying the idea of DRC to the LPM problem makes the prefixes comparable like numbers using a pair of w-bit vectors to store at least one and at most w prefixes, where w is the IP address length. This leads to good compression performance. Based on this, two recently introduced structures called coded prefix trees and scalar prefix trees are shown to be specific applications of DRC. They are implementable on balanced trees which cause the node access complexity for prefix search and update procedures to be O(log n) where n is the number of prefixes. As another advantage, the number of node accesses for these procedures does not depend on w. Additionally, they need fewer number of node accesses compared to recent range-based solutions. These structures are applicable on both IPv4 and IPv6, and can be implemented in software or hardware.

• Bulletin of the Korean Chemical Society
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• 제20권10호
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• pp.1177-1180
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• 1999

The ab initio SCF MO and density functional theory (DFT) studies are carried out on the electrophilic (1a) and electron transfer (1b) addition reactions to the vinyl double bond of aryl vinyl sulfides and ethers. In the electrophilic addition processes, a double bond shift from C3 = C4 to X = C3 occurs with occupation number (1.97) close to the normal two. Due to this shift direct conjugation between the cationic center, X = S or O, and the para electron-donor substituent becomes impossible so that the reaction energies (or log K) are correlated with σ rather than σ+. By contrast, radical cation formation leads to delocalization of the SOMO, a lone-pair πorbital on X, with four major resonance structures in which cationic charge as well as spin density is delocalized over C4 , X and C7 atoms. As a result, partial πbonds are formed over C1 -X and C3 - C4 with occupation numbers (0.82) lower than one. In two of the cannonical structures, III(Ⅹ) and III(X+), direct conjugation between the cationic center, X, and the para substituent is achieved so that a better correlation with σ+ rather than σis obtained. The SCF MO energies at the HF/3-21G* and HF/6-31G* levels lead to very much inferior Hammett correlations in the σ/ σ+ diagnostic criterion. In contrast, the ρvalues evaluated with the DFT energies can give reliable diagnostic distinction between the two addition mechanisms.

• 국제물리치료학회지
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• 제9권4호
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• pp.1657-1662
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• 2018

This epidemiological study aims to determine the incidence, areas, severity, and time of occurrence of sports injuries in elite female rowing athletes who were training at the Jincheon National Training Center for a 1-year period from January 1st to December 31st, 2017. According to the daily injury reports form of the IOC, sport events, weight division, injured area, and cause of injury were recorded, and the following results were found. Upon comparing the incidence of sports injuries, there was a significant difference in weight of double scull athletes. In terms of sports, there was a significant difference between pair and athletes who played double skull. Injuries occurred most commonly in the lower extremity (40.5%), followed by the trunk (35.1%), upper extremity (24.3%). for all athletes in rowing. The knee and lumbar spine/lower back were the most common injury sites. More than 60% of all injuries were Level III, and injuries occurred most frequently during training, followed by weight training and then competition.

• Journal of Astronomy and Space Sciences
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• 제40권4호
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• pp.259-266
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• 2023

The Standard Model (SM) does not provide an information for 26% of dark matter of the universe. In the dark sector, dark matter is supposed to be linked with the hypothetical particles called dark photons that have similar role to photons in electromagnetic interaction in the SM. Besides astronomical observation, there are studies to find dark matter candidates using accelerators. In this paper, we searched for dark photons using future electron-positron colliders, including Circular Electron Positron Collider (CEPC)/CEPC, Future Circular Collider (FCC-ee)/Innovative Detector for Electron-positron Accelerator (IDEA), and International Linear Collider (ILC)/International Large Detector (ILD). Using the parameterized response of the detector simulation of Delphes, we studied the sensitivity of a double dark photon mode at each accelerator/detector. The signal mode is double dark photon decay channel, e⁺e^- → A'A', where A' (dark photon with spin 1) decaying into a muon pair. We used MadGraph5 to generate Monte Carlo (MC) events by means of a Simplified Model. We found the dark photon mass at which the cross-sections were the highest for each accelerator to obtain the maximum number of events. In this paper we show the expected number of dark photon signal events and the detector efficiency of each accelerator. The results of this study can facilitate in the dark photon search by future electron-positron accelerators.