http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
CMS에서 전력제어를 위한 AGC의 성능 개선에 관한 연구
이원구,이철희,천종훈,박수봉,박종안,신용길 조선대학교 동력자원연구소 1996 動力資源硏究所誌 Vol.18 No.1
CDMA 시스템에서는 이동국이 Open-loop 전력제어 및 Close-Loop 전력제어를 할 때 비 선형적인 AGC의 특성으로 인해 수신기의 감도가 현저히 낮아진다. 본 논문에서는 AGC의 비선형적인 특성 곡선값을 S/W로 선형화 시켜 RAS RAMDATA를 생성하고 이를 RAS RAM에 넣어 선형적으로 보상된 AGC특성을 얻는 알고리즘을 제안하였다. 그리고 실험을 통하여 그 유효성을 증명한다. In CDMA system, the sensitivity of receivers is lowered significantly due to characteristics of non-linear AGC when the mobile station implements open-loop power control and closed-loop power control. In this paper, We propose a algorithm that obtains linearly conpensated AGC characteristic by inserting the RAS RAM DATA in RAS RAM, which linearizes the value of non-linear characteristic graph in AGC by S/W, and the experimental results shows the validity.
CDMA기반 IMT-2000 시스템에서 Processing Gain에 따른 최대 가입자 용량 분석
이철희,양원일,박종안 조선대학교 전자정보통신연구소 2001 電子情報通信硏究所論文誌 Vol.4 No.2
본 논문에서는, 현재 상용되고있는 디지털 셀룰러와 PCS를 기반으로 IS-98A와 J-STD-018 규격에 준하는 이동 통신용 수신 시스템의 고주파부 파라미터 성능을 분석하고, 앞으로 상용화될 IMT-2000 수신시스템의 잡음지수, 데이터 전송률에 따른 처리이득, 처리이득에 따른 단말기 잡음지수, 처리이득에 따른 최대 가입자수를 예측하는데 주안점을 두고 분석하였다. 시뮬레이션 환경은 CDMA 2000의 선두주자인 퀄컴사와 NTT에서 주장하는 전송대역폭을 1.25㎒, 5㎒, 10㎒, 20㎒로 하고, 2세대 이동통신의 데이터 전송속도 보다 10~200배 빠른 속도를 요하는 데이터 전송률을 이동자동차 환경에서 144Kbps, Outdoor 보행자 환경에서 384Kbps, Indoor office 환경에서는 2Mbps로 각각 분류하여 시뮬레이션 하였다. 시뮬레이션 결과는 확산신호 대역폭과 데이터 신호 대역폭이 CDMA나 PCS에 비해 넓어짐에 따라 수신감도가 낮아짐을 알 수 있었다. 확산 신호 대역폭이 20MHz일 경우 IMT2000에서는 최대 사용자수가 32명인 CDMA 이동자동차 환경과 비교해 약 2명 정도 증가됨을 보였고, 이동 보행자 환경에서는 약 13명, 고정사무실 환경에서는 2.5명 정도의 최대 가입자 수를 나타내었다. In this paper, we analyse the parameter performance of high frequency part of receiving system for mobile telecommunication comparable to IS-98A and J-STD-018 specification based on commercially available digital cellular and PCS, and anticipate the performance such as processing gain of IMT-2000 receiving system, receiving sensitivity according to the data processing rate, maximum capacity according to the processing gain. The simulation environments are 1.25 MHz, 5 MHz, 10 MHz, 20 MHz of transmission bandwidth recommended by Qualcomm and NTT, the leading company in CDMA 2000, and we classify data transmission rate of IMT-2000 which requires more higher speed of 10~ 200 times than data transmission speed of second generation mobile communications into three cases as in moving vehicle environment of 144Kbps, outdoor pedestrian environment of 384Kbps, indoor office environment of 2Mbps, and simulate that. Simulation results show that the receiving sensitivity is decreased according that bandwidths of spread-spectrum signal and data signal are widen than CDMA and PCS. When the bandwidth of spread-spectrum signal is 20MHz, the maximum capacity of IMT-2000 is 34 user, and this result show that the capacity is increased about 2 user in CDMA moving vehicle environment that the maximum capacity is 32 user, 13 user in moving pedestrian environment, and 2.5 user in indoor office environment.
집합주거단지에서 건강환경 조성을 위한 주거동의 배치유형이 통풍계획에 미치는 영향 분석
조철희,이특구 한국의료복지시설학회 2004 의료·복지 건축 Vol.10 No.2
The purpose of this study is to analyze the wind velocity ratio in respect of layout types of housing in multi-family housing. The wind velocity ratio is a difference of wind velocity between on the leeward and on the windward side of multi-family housing. The layout types of housing are grid layout pattern of linear type, mixture pattern of Linear type + tower type and layout pattern of tower type. The planning of wind flow is an induced technique to increase in wind velocity in the city and multi-family housing. This study investigates wind velocity ratio into layout types of housing. consequently, analysis were basic design data for the planning techique of wind flow suggested.
최재희,박진철,김성만,김용철,이충열,박현철,최인수 밀양대학교 농업기술개발연구소 2000 農業技術開發硏究所報 Vol.4 No.1
Effects of photoperiod(23L or 24D) to the growth of the silkworn vegetable wasp and plant worm were investigated. Exposure of the fungi to 24L photoperiod for at least 3 days accelerated the formation of the spore, but the growth of the fruiting bodies was inhibited. On the contrary, 24D photoperiod inhibited the spore formation, but accelerated the growth of fruiting bodies. Accordingly to harvest high quality silkworm vegetable wasp and plant worm, it is suggested that recommendable light condition for production of longer fruiting bodies is 24D photoperiod during the cultivation.
정종철,최홍란,오희균,박준아,류선열,이종호,김영운,정숭룡 大韓顎顔面成形再建外科學會 1995 Maxillofacial Plastic Reconstructive Surgery Vol.17 No.3
Malignant fibrous histiocytoma rarely occurs in the jaws. Although the histogenesis of this tumor remains controversal, it is best regarded as a primitive and pleomorphic nature reflected by collagen production and occasional phagocytosis. It is common for metastatic foci to appear in lung and regional lymph node. There are variable treatments such as radiotherapy, surgical excision or combination, therapy of surgical excision, chemotherapy and radiotherapy. With the review of literatures, the authors report the clinical study of two cases of malignant fibrous histiocytoma of the jaw.
자가 산부식 프라이머의 적용시간이 상아질의 미세인장 결합강도에 미치는 영향
조영곤,이영곤,김종욱,박병철,김종진,최희영,진철희,유상훈 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.5
This study evaluated the influence of application time of self-etching primers on microtensile bond strength (μTBS) to dentin using three self-etching primer adhesive systems. Dentin surfaces were exposed from forty-eight human molars. They were conditioned with three self-etching primers (Clearfil SE Bond [SE], Unifil Bond [UF], Tyrian SPE + One Step Plus [TY]) and different primining times (10s, 20s, 30s and 40s). Composite resins were bonded to dentin surfaces and specimens were made. μTBS was tested and statistically compared using by one-way ANOVA and Tukey's Test. The results of this study presented that priming time for 10s in SE and UF groups and for 30s and 40s in TY group was highly decreased μTBS to dentin.
Lim, Mi-Hee,Jeung, In Cheul,Jeong, Jinyoung,Yoon, Sung-Jin,Lee, Sang-Hyun,Park, Jongjin,Kang, Yu-Seon,Lee, Hansu,Park, Young-Jun,Lee, Hee Gu,Lee, Seon-Jin,Han, Baek Soo,Song, Nam Woong,Lee, Sang Chul Elsevier 2016 Acta Biomaterialia: structure-property-function re Vol.46 No.-
<P><B>Abstract</B></P> <P>Despite the rapid expansion of the biomedical applications of graphene oxide (GO), safety issues related to GO, particularly with regard to its effects on vascular endothelial cells (ECs), have been poorly evaluated. To explore possible GO-mediated vasculature cytotoxicity and determine lateral GO size relevance, we constructed four types of GO: micrometer-sized GO (MGO; 1089.9±135.3nm), submicrometer-sized GO (SGO; 390.2±51.4nm), nanometer-sized GO (NGO; 65.5±16.3nm), and graphene quantum dots (GQDs). All types but GQD showed a significant decrease in cellular viability in a dose-dependent manner. Notably, SGO or NGO, but not MGO, potently induced apoptosis while causing no detectable necrosis. Subsequently, SGO or NGO markedly induced autophagy through a process dependent on the c-Jun N-terminal kinase (JNK)-mediated phosphorylation of B-cell lymphoma 2 (Bcl-2), leading to the dissociation of Beclin-1 from the Beclin-1–Bcl-2 complex. Autophagy suppression attenuated the SGO- or NGO-induced apoptotic cell death of ECs, suggesting that SGO- or NGO-induced cytotoxicity is associated with autophagy. Moreover, SGO or NGO significantly induced increased intracellular calcium ion (Ca<SUP>2+</SUP>) levels. Intracellular Ca<SUP>2+</SUP> chelation with BAPTA-AM significantly attenuated microtubule-associated protein 1A/1B-light chain 3-II accumulation and JNK phosphorylation, resulting in reduced autophagy. Furthermore, we found that SGO or NGO induced Ca<SUP>2+</SUP> release from the endoplasmic reticulum through the PLC β3/IP<SUB>3</SUB>/IP<SUB>3</SUB>R signaling axis. These results elucidate the mechanism underlying the size-dependent cytotoxicity of GOs in the vasculature and may facilitate the development of a safer biomedical application of GOs.</P> <P><B>Statement of Significance</B></P> <P>Graphene oxide (GO) have received considerable attention with respect to their utilization in biomedical applications. However, GO-related safety issues concerning human vasculature are very limited. In this manuscript, we report for the first time the differential size-related biological effects of GOs on endothelial cells (ECs). Notably, Subnanometer- and nanometersized GOs induce apoptotic death in ECs via autophagy activation. We propose a molecular mechanism for the GO-induced autophagic cell death through the PLCβ3/IP3/Ca<SUP>2+</SUP>/JNK signaling axis. Our findings could be provide a better understanding of the GO sizedependent cytotoxicity in vasculature and facilitate the future development of safer biomedical applications of GOs.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>