• Journal of Energy Engineering
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• v.24 no.2
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• pp.103-109
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• 2015

A heat recovery steam generator consists of inlet expansion duct and heat transfer tube bank modules. For the enhancement of heat transfer in the tube bank modules, the flow should be uniform before the 1st heat transfer tube bank module. The present study has been carried out to analyze the flow characteristics in the inlet expansion duct of a heat recovery steam generator by using numerical flow analysis. The aim of the present study is to establish the proper heat transfer mechanism in the heat transfer tube bank modules by the comparison of the heat transfer models, the case with the constant heat loss per unit volume and the case with heat loss by using inner and outer convective heat transfer coefficient of heat transfer tube. From the present research, it could be seen that the heat transfer mechanism with using inner and outer convective heat transfer coefficient derives more proper temperature distribution results and the acceptance criteria of the temperature distribution within ${\pm}10^{\circ}C$ before SCR is satisfied with using this heat transfer mechanism.

• Journal of Internet Computing and Services
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• v.3 no.2
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• pp.79-85
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• 2002

In open communication architecture, application systems consist of objects distributed in lots of computing nodes. To reduce complexity of development. and management of distributed software, to manage efficiently distributed objects and to provide realtime service, the mechanisms for object group management and communication are needed in distributed environment. In this paper we compose object groups and provide reliable group communication mechanism based on CORBA which can adopt a new service without lots of changes on existing system. Group consist of some subgroups that subgroup manager manages for improving the efficiency of group management and message ordering is kept by using sequencer, Communication method among groups uses multicast based on paint to point communication as well as IP multicast and we provide high performance by using selective retransmission of message through message history, We analyze the performance of the proposed mechanism through simulation in distributed environment.

• Proceedings of the KIEE Conference
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• 1999.07d
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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.

• Journal of Environmental Health Sciences
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• v.21 no.3
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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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• v.30 no.6
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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.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.1 no.1
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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.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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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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• v.7 no.3
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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.

• Proceedings of the KIEE Conference
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• 1998.07d
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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.

• Korean Journal of Biological Psychiatry
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• v.23 no.1
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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.