• Journal of the Institute of Electronics Engineers of Korea TC
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• 제41권8호
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• pp.1-7
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• 2004

The effect of the sub-optimal beam-forming and the fading channel correlation on the closed loop transmit antenna diversity(CTD) system is investigated in frequency flat Rayleigh fading channels. The fast channel fading prevents the perfect channel estimation at a mobile station, hence the imperfect weight is applied to the antenna branch of transmitter. The weight causes sub-optimalbeam-forming and aggravates the performance of CTD system. The fading correlation or a wireless channel also is one of the factors decreasing the diversity gain. A bit error rate expression for the CTD system is analytically derived as a function of the channel estimation error, the channel correlation coefficient the feedback delay, and fading index. It is shown that the channel estimation error gives more severe effect to the system performance than the channel correlation.

• Journal of Korea Multimedia Society
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• 제14권11호
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• pp.1383-1391
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• 2011

Following the appearance of the latest medical equipment with improved function, the importance of image analysis which enables effective image processing and analysis consistent with the hardware performance is on the rise. As well as, ongoing study is being done on the 2D medical image processing and 3D reconstruction. This paper segments chest CT images into each stage and finally shows 3D reconstruction of each segmented result. Among various image segmentation methods, Region Growing and apply sharpening and Gamma Controller as for image improvement for effective segmentation, image segmentation in order of bronchus and lung, bronchus, lung. Human organs image of segmented is use VTK(Visualization Toolkit) to make 3D reconstruction, two and three-dimensional medical image processing and analysis for lesions diagnosis are able to utilized.

• Journal of the Korean Institute of Intelligent Systems
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• 제23권4호
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• pp.281-285
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• 2013

In this paper, a design scheme of a cruise control system for an electric vehicle using piece-wised PD control is proposed. Cruise control of electric vehicles is one of the major performance elements. Drive motors having linear characteristics ideally is required in order to achieve the cruise driving. But practical motors have nonlinear characteristics and the performance of the motors can be improved by the closed-loop control to compensate it. In this paper, we improved the performance of by applying piece-wised PD control because the driving motors having nonlinear characteristics are difficult to obtain adequate performance only using closed-loop control. In order to test the proposed method, the experiments were carried out by applying the proposed method after setting up an electric vehicle equiped with a driving motors having large nonlinear characteristics. The experiment results of the proposed piece-wised PD control shows better performance than that of closed-loop control.

• Journal of the Mineralogical Society of Korea
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• 제22권4호
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• pp.353-358
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• 2009

The ability of natural abrasives which were recovered from CRT glass polishing process was evaluated. Comparing the center line average roughness values of a glass polished with new pumice (Ra = $0.039{\mu}m$) and with new garnet (Ra = $0.031{\mu}m$), the glass surface polished with the recycled pumice and the garnet had less pits on the surface with smaller Ra values (Ra = $0.025{\mu}m$ for recycled pumice and Ra = 0.029 for recycled garnet). Recycled rouge contains amorphous glass fragments so that it should be used as a cement replacement rather than recycle into an abrasive. Nnatural abrasives, pumice and garnet powder, which are used in CRT glass polishing process can be recycled into abrasives so that it can help to minimize costs and environmental impact from the production of abrasives and the disposal of waste sludge.

• Journal of the Korean Society of Propulsion Engineers
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• 제16권4호
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• pp.80-86
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• 2012

This study is for figuring out a possibility of realization of the thermal protection system(TPS) for temporary use under high temperature condition and improving a design of the future TPS. On this purpose, environmental condition of the system has been simplified: the boundary conditions consist of a internally heating surface and a externally heated surface which is simulating the external high temperature condition. Configuration of the system is simplified as a hexahedon. Melting characteristics of the phase change material(PCM) and air temperature variation of TPS with or without connector have been numerically analyzed and compared. As a result of numerical analysis, the heat from the internally heated surface could not be effectively transferred. Therefore, temperature of inner space has been increased.

• Tuberculosis and Respiratory Diseases
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• 제52권2호
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• pp.179-185
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• 2002

A bronchus-associated lymphoid tissue(BALT) lymphoma of the lung is a rare disorder of patients with Sj$\ddot{o}$gren's syndrome. A 49-year-old woman was admitted for an evaluation of exertional dyspnea and general weakness which had persisted for two years. The patient had suffered from dry mouth and dry eyes for five years. The physical examinations showed a coarse breath sound with inspiratory crackles on the whole lung field, particularly on the both basal lungs. The laboratory data disclosed high titers of anti-nuclear antibodies, and anti-SSA (Ro), and anti-SSB (La) antibodies. Chest radiographs demonstrated the presence of bilateral, diffuse, reticulonodular densities in both lungs. Thin-section CT scans showed diffusely distributed mosaic pattern of an inhomogeneous attenuation extending over the entire lung zone. The histological findings from an open-lung biopsy specimen revealed an accumulation of lymphoid cells around the bronchioles and an extension of malignant lymphoma cells from the bronchiolar epithelium toward the alveolar space. Immunohistochemically, the neoplastic cells reacted positively to the CD 20 antigen and were focally positive for the UCHL 1 antigen. The histological diagnosis was consistent with a low grade marginal zone B-cell lymphoma originating in the BALT. Here, we present a case of a histologically proven BALT lymphoma of the lung in a patient with primary Sj$\ddot{o}$gren's Syndrome.

• Journal of Life Science
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• 제19권12호
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• pp.1847-1850
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• 2009

Bovine tuberculosis is generally detected postmortem because it is a chronic debilitating disease. Since tuberculosis is mainly found in the lungs, clinical signs including coughing, nasal discharge, and difficulty breathing can occur in severe instances. In the present study, specimens were collected from the heart, liver, kidney, lung, pleural cavities, lymph nodes and intestines of carcasses found in an abattoir. According to post-mortem examination and inspection of carcasses, tuberculosis lesions were varied in appearance and size. Tubercles of a white cream color were disseminated throughout the pleural cavity including the lymph nodes, lungs and mesentery containing pus. Gram and Ziehl-Neelsen's acid-fast staining for the lung and lymph nodes revealed a highly positive histochemical reaction. The acid-fast organisms were observed histologically in the lesions under a microscope. This report demonstrated the histopathology of bovine tuberculosis based on the histological findings of Mycobacterium bovis, which is a suspected causative agent.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 한국마이크로전자및패키징학회 2001년도 추계 기술심포지움
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• pp.205-208
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• 2001

본 연구에서는 소결온도와 치환원소에 따른 서클레이터/아이솔레이터용 YIG 페라이트의 미세구조와 전자기적 특성을 고찰하고자 하였다. Ca, V, In을 치환시킨 YIG 페라이트를 분무건조기를 사용하여 준구형 과립상태로 만들고, 일반적인 세라믹 제조 공정에 따라 12$50^{\circ}C$, 1275$^{\circ}C$, 130$0^{\circ}C$, 13$25^{\circ}C$에서 각각 소결하였다. 제조된 YIG 페라이트에 대한 기본 물성과 자기 특성을 밀도측정기, XRD, SEM, VSM, FMR(Ferromagnetic Resonance) 등을 이용하여 측정 분석하였다. $Y_{1.6}$C $a_{1.4}$F $e_4$ $V_{0.7}$I $n_{0.3}$ $O_{12}$ 조성의 YIG 페라이트에 대한 전자기적 특성 측정 결과 130$0^{\circ}C$에서 소결한 YIG 페라이트가 높은 포화자화(4$\pi$Ms) 값과 낮은 자기공명반치폭($\Delta$H)을 지닌 우수한 전자기적 특성을 나타내었다. 전자기적 특성을 나타내었다.나타내었다.다.

• Environmental Mutagens and Carcinogens
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• 제10권2호
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• pp.135-145
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• 1990

Silver-binding nucleolar organizer regions (Ag-NORs)염색법을 이용하여 in vivo 및 in vitro에서 발암과정과 관련된 세포증식능을 검토하였다. A/J마우스에 benzo (a) pyrene을 투여하여 유발된 폐선종, 폐선암 및 Sprague-Dawley랫트에 dimethylbenz (a) anthracene투여에 의해 발생된 유선의 선암세포에서 Ag-NORs의 염색상태를 정상 조직과 비교하여 또한 정상마우스 섬유모세포인 NIH3T3에서의 Ag-NORs의 수 및 DNA 증식 억제물질인 caffeine에 의한 변화를 관찰하였다. 은친화성 NOR과련 단백질은 핵내 흑색의 반점으로 나타났으며 정상 폐조직의 세포당 Ag-NORs 수치는 0.87+0.01였으며 양성종양인 폐선종세포 및 악성종양인 폐선암세포에서는 각각 2.33+0.02, 2.56+0.45 정상 유선조직의 세포당 Ag-NORs수치는 1.21+0.16였으며 악성종양인 선암세포는 3.91+0.11로써 종양성 병변에서 유의한 증가를 보였다 (P<0.005).

• Journal of Environmental Science International
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• 제11권9호
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• pp.993-999
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• 2002

Waste paper cup was sulfonated to be used as ion exchanger. Removal characteristic of copper and lead ion by prepared ion exchanger was investigated. The sulfonation was conformed by the high intensity band of $SO_3H$ group around 1100~$1160cm^{-1}$. The synthesized ion exchanger had greater removal ability for copper and lead ion than the original waste paper cup. Ion exchange system reached the final equilibrium plateau within 30min. The maximum removal capacities $q_{max}$ were calculated as 9.79mg/g fur copper and 15.95mg/g for lead, respectively. The affinity of lead based on a weight was higher than that of copper. The ion exchange phenomena appeared to follow a typical Freundlich isotherm.