• 에너지공학
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• 제24권2호
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• pp.103-109
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• 2015

배열회수 보일러는 입구 확관 덕트와 전열관군으로 이루어져 있는데 전열관군에서 열전달 효율을 향상하기 위해서는 전열관군 전에서 배기가스 유동이 균일하게 되어야 한다. 본 연구에서는 전열관군 전의 배열회수 보일러 입구 덕트에서 유동 특성을 살펴보았고 전열관군의 열전달 메커니즘을 지금까지 다른 연구들에서 적용하였던 일정한 열전달 량으로 한 경우와 전열관군 배관의 내부와 외부의 대류열전달을 고려한 열전달 메커니즘을 적용한 경우의 해석에서 온도 분포를 비교하여 배열회수 보일러의 전열관군에서 실제 현상에 보다 적합한 열전달 메커니즘을 정립하는 것을 목적으로 하였다. 본 연구를 통하여 전열관군 배관의 내부와 외부의 대류열전달을 고려한 열전달 메커니즘을 적용한 해석이 일정한 열전달 량을 적용한 경우보다 온도 분포가 타당한 결과를 도출하였고 이렇게 적용한 경우는 배열회수 보일러 탈질설비 전단에서 온도 분포가 설계 기준 ${\pm}10^{\circ}C$에 만족함을 알 수 있었다.

• 인터넷정보학회논문지
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• 제3권2호
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• pp.79-85
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• 2002

개방형 통신망 구조에서 어플리케이션 시스템은 다수의 컴퓨팅 노드에 분산되어 있는 객체들의 집합으로 구성된다. 이러한 분산된 환경에서 복잡한 분산 소프트웨어의 개발 및 관리의 복잡성을 줄이고 분산된 객체들을 효율적으로 관리하면서 객체들의 실시간 서비스를 제공하기 위해서는 객체 그룹 관리 및 통신 기법이 필요하다. 본 연구에서는 CORBA를 기반으로 하여 기존의 시스템에 큰 변환 얼이 새로운 서비스를 적용시킬 수 있도록 객체그룹을 구성하고 신뢰성 있는 그룹통신 기법을 제공한다. 그룹관리의 효율향상을 위해 그룹을 서브그룹으로 나누고 서브그룹 관리자를 두어 서브그룹을 관리하도록 하였으며, 시퀀서를 두어 메시지의 순서성을 유지시킨다. 그룹간의 통신방법은 IP 멀티캐스트와 일대일 통신을 기반으로 한 멀티캐스트 기법을 혼용하여 사용하며 메시지 저장소를 두어 오류 발생 시 선택적으로 메시지를 재 전송할 수 있도록 함으로서 성능을 향상시켰다. 제안된 기법을 분산환경에서 시뮬레이션을 통하여 성능을 평가하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 D
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• pp.1535-1537
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• 1999

Photochemical defluorination and substitution of fluorocarbon-resin surfaces using a pulsed Nd:YAG laser(266 nm) and copper-sulfate$(CuSO_4)$ aqueous solution were discussed. Interface of copper nuclei and fluorocabon-resin was chemically bonded through oxygen which was photodissociated from water in copper-sulfate aqueous solution under the laser irradiation. The reaction mechanism for chemical surface modification is discussed on the basis of x-ray photoelectron spectroscopy and atomic force microscope analyses.

• 한국환경보건학회지
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• 제21권3호
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• pp.87-95
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• 1995

A rapid and selective co-extraction systems of copper and zinc-thiocyanate complex into various types of alkylamine for the simultaneous determination of two metal ions by atomic absorption spectrometry and ion chromatograph have been proposed. The quantitative extractions of Cu(II) and Zn(II) at 0.1 M-thiocyanate and 0.1 M-HCI were achieved with Aliquat 336-$CHCl_3$. The detection limits of Cu and Zn were 2 ppb and 0.9 ppb respectively.

• ETRI Journal
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• 제30권6호
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• pp.783-789
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• 2008

A bio-inspired vision chip for edge detection was fabricated using 0.35 ${\mu}m$ double-poly four-metal complementary metal-oxide-semiconductor technology. It mimics the edge detection mechanism of a biological retina. This type of vision chip offer several advantages including compact size, high speed, and dense system integration. Low resolution and relatively high power consumption are common limitations of these chips because of their complex circuit structure. We have tried to overcome these problems by rearranging and simplifying their circuits. A vision chip of $160{\times}120$ pixels has been fabricated in $5{\times}5\;mm^2$ silicon die. It shows less than 10 mW of power consumption.

• 대한정형도수물리치료학회지
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• 제1권1호
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• pp.85-97
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• 1995

Orthopaedic medicine was developed and published by James Cyriax, a British Orthopaedic Physician on 1929. Orthopaedic medicine is concerned with the diagnosis and treatment of soft tissue lesions. These disorders affect a substantial proportion of all patients in general and in particular, physiotherapy and sports clinics. In broad terms these disorders em trace conditions. such as arthritis. rheumatism. fibrositis. backache. lumbago, sciatica, frozen shoulder, tennis elbow, strained wrist, sprains, aches, inflanmation and sports injuries generally. The soft Moving tissues share one thing in common - they are all radiotranslucent and the tissues in question are the joint capsule, the ligaments, the fasciae, dural sheath. These structures can cause pain but none of them is visible on the radiograph. Dr. Cyriax divided all soft tissues into two basic types : 1) Contractile tissue, 2) Inert or noncontractile tissue. The mechanism of diagnosis is tension applied manually. The physician subjects each tissue about the incriminated joint to tension in turn which they call 'Selective tension' with Cyriax's assessment, a more definitive diagnosis can be obtained and proper treatment can be implemented.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.242-242
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• 1996

The influence of glucocorticoids on the secretory responses of catecholamines (CA) evoked by acetylcholine (ACh), DMPP, McN-A-343, excess K$\^$+/ and Bay-K-8644 from the isolated perfused rat adrenal gland and to clarify the mechanism of its action. The perfusion of the synthetic glucocorticoid dexamethasone (10-100 uM) into an adrenal vein for 20min produced relatively a dose-dependent inhibition in CA secretion evoked by ACh (5.32mM), excess K$\^$+/ (56mM), DMPP (a selective nicotinic receptor agonist, 100uM for 2min), McN-A-343 (a muscarinic receptor agonist, 100uM for 4min), Bay-K-8644 (a calcium channel activator, 10 uM for 4min) and cyclopiazonic acid (a releaser of intracellular Ca$\^$2+/, 10uM for 4min).

• Journal of Communications and Networks
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• 제7권3호
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• pp.385-393
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• 2005

In this paper, we propose a simple algorithm to adaptively adjust the value of dupthresh, the duplicate acknowledgement threshold that triggers the transmission control protocol (TCP) fast retransmission algorithm, to improve the TCP performance in a network environment with persistent packet reordering. Our algorithm uses an exponentially weighted moving average (EWMA) and the mean deviation of the lengths of the reordering events reported by a TCP receiver with the duplicate selective acknowledgement (DSACK) extension to estimate the value of dupthresh. We also apply an adaptive upper bound on dupthresh to avoid the retransmission timeout events. In addition, our algorithm includes a mechanism to exponentially reduce dupthresh when the retransmission timer expires. With these mechanisms, our algorithm is capable of converging to and staying at a near-optimal interval of dupthresh. The simulation results show that our algorithm improves the protocol performance significantly with minimal overheads, achieving a greater throughput and fewer false fast retransmissions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1288-1290
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• 1998

Three most dominant reactions are adsorption, movement, and desorption of $SiCl_2$ on silicon surface. $SiCl_2$ plays a key role in these dominant reactions. In this paper, surface reactions of $SiH_2Cl_2-H_2-HCl$ system are investigated and few dominant reactions were identified. An equation for Si net growth rate is derived from the analysis of these reactions and it is compared with experimental results of Bolem and Classen.

• 생물정신의학
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• 제23권1호
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• pp.1-11
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• 2016

Development of various antidepressants such as monoamine oxidase inhibitors, tricyclic antidepressants, selective serotonin reuptake inhibitors, serotonin norepinephrine reuptake inhibitors, and noradrenergic and specific serotonergic antidepressant has led to a tremendous progression of pharmaceutical treatment for depression, but still there are some limitations of current antidepressants, such as treatment-resistant depression and delayed onset of antidepressants. The pathogenesis of depression is unclear because depression is a heterogeneous disease state, and the mechanisms of antidepressants remain uncertain as well. Nevertheless, in an attempt to develop novel antidepressants, some trials have been conducted based on the potential biological mechanism discovered in the numerous research results. This review will provide information about the potential novel antidepressants and the current states of clinical studies using them. In particular, some potential novel antidepressants anti-inflammatory agents, antioxidants, anticholinergics, modulators of Hypothalamic Pituitary Adrenal Axis, glutamate, and opioid systems, as well as some neuropeptides such as susbstance P, neuropeptide Y, and galanin will be discussed.