• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.6
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• pp.21-30
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• 2022

This paper describes the design, manufacture, and testing of servos applicable to small tracking radars. First, Chapter 1 describes the necessity of this study. Chapter 2 describes the development of servos applicable to future tracking radars in small missile systems. Chapter 3 describes the design and test results for current control of brushed DC motors, brushless DC motors, and permanent magnet synchronous motors. And Chapter 4 describes the design and test results for speed control of the test wheel. And in Chapter 5, the results of the previous tests are summarized. In this paper, some pictures were intentionally blurred for security reasons, and the control result of test wheel was described, not the test with the developed gimbals.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.1C
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• pp.53-61
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• 2008

In this paper, we propose an algorithm for generation of multi-view video from conventional 2 dimensional video. Color and motion information of an object are used for segmentation and from the segmented objects, multi-view video is generated. Especially, color information is used to extract the boundary of an object that is barely extracted by using motion information. To classify the homogeneous regions with color, luminance and chrominance components are used. A pixel-based motion estimation with a measurement window is also performed to obtain motion information. Then, we combine the results from motion estimation and color segmentation and consequently we obtain a depth information by assigning motion intensity value to each segmented region. Finally, we generate multi-view video by applying rotation transformation method to 2 dimensional input images and the obtained depth information in each object. The experimental results show that the proposed algorithm outperforms comparing with conventional conversion methods.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.4
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• pp.409-415
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• 2011

Purpose: To design applied anamorphic lens that focal length ratio is 3:1 optical system to improve detecting distance. Methods: We defined a boundary condition as $50^{\circ}{\sim}60^{\circ}$ for viewing angle, horizontal direction 36mm, vertical direction 12 mm for focal length, f-number 4, $15{\mu}m{\times}15{\mu}m$ for pixel size and limit resolution 25% in 33l p/mm. Si, ZnS and ZnSe as a materials were used and 4.8 ${\mu}m$, 4.2 ${\mu}m$, 3.7 ${\mu}m$ as a wavelength were set. optical performance with detection distance, narcissus and athermalization in designed camera were analyzed. Results: F-number 4, y direction 12 mm and x direction 36 mm for focal length of the thermal optical system were satisfied. Total length of the system was 76 mm so that an overall volume of the system was reduced. Astigmatism and spherical aberration was within ${\pm}$0.10 which was less than 2 pixel size. Distortion was within 10% so there was no matter to use as a thermal optical camera. MTF performance for the system was over 25% from 33l p/mm to full field so it was satisfied with the boundary condition. Designed optical system was able to detect up to 2.9 km and reduce a diffused image by decreasing a narcissus value from all surfaces except the 4th surface. From sensitivity analysis, MTF resolution was increased on changing temperature with the 5th lens which was assumed as compensation. Conclusions: Designed optical system which used anamorphic lens was satisfied with boundary condition. an increasing resolution with temperature, longer detecting distance and decreasing of narcissus were verified.

• Tuberculosis and Respiratory Diseases
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• v.42 no.1
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• pp.58-66
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• 1995

Background: Acute interstitial pneumonia is a relatively rare form of interstitial pneumonia, since the vast majority of interstitial pneumonia have a more chronic course. It corresponds to the lesion described by Hamman and Rich, as Hamman-Rich disease in 1944. Another name in the clinical literature is accelerated interstitial pneumonia, idiopathic acute respiratory distress syndrome (idiopathic ARDS), and the organizing stage of diffuse alveolar damage. Acute interstitial pneumonia differs from chronic interstitial pneumonia by clinical and pathologic features. Clinically, this disease is characterized by a sudden onset and a rapid course, and reversible disease. Method and Purpose: Five cases of pathologically proven acute interstitial pneumonia were retrospectively studied to define the clinical, radiologic, and pathologic features. Results: 1) The five cases ranged in age from 31 to 77 years old. The onset of illness was acute in all patients, it began with viral-like prodrome 6~40 days prior to shortness of breath, and respiratory failure eventually developed in all patients. In 2 cases, generalized skin rash was accompanied with flu-like symptoms. Etiologic agent could not be identified in any case. 2) All patients had leukocytosis and severe hypoxemia. Pulmonary function test of 3 available cases shows restrictive ventilatory defect, and one survived patient(case 5) has a complete improvement of pulmonary function after dismissal. 3) Diffuse bilateral chest infiltrates were present radiologically. Theses were the ground-glass, consolidation, and reticular densities without honeycomb fibrosis in all patients. The pathologic abnormalities were the presence of increased numbers of macrophages and the formation of hyaline membranes within alveolar spaces. There was also interstitial thickening with edema, proliferation of immature fibroblast, and hyperplasia of type II pneumocyte. In the survived patient(case5), pathologic findings were relatively early stage of acute interstitial pneumonia, such as hyaline membrane with mild interstitial fibrosis. 4) Of the 5 patients, four patients died of respiratory failure 14~90 days after onset of first symptom, and one survived and recovered in symptoms, chest X ray, and pulmonary function test Conclusion: These results emphasize that acute interstitial pneumonia is clinically, radiologically, and pathologically distinct form of interstitial pneumonia and should be separated from the group of chronic interstitial pneumonia. Further studies will be needed to evaluate the pathogenesis and the treatment of acute interstitial pneumonia.

• The Journal of the Petrological Society of Korea
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• v.17 no.3
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• pp.166-178
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• 2008

The modal analyses on the phenocryst phases and the normative mineralogies from the bulk chemical analyses record that the volcanic rocks related to the Yangsan caldera might been derived from compositionally zoned magma. The volcanic rocks show linearly continuous mineralogical gradients, not only totally in the relations between $SiO_2$ and proportion of phenocryst content, but also within each rock unit in the relations between total phenocryst content and the proportion, Q-Ab-Or and Q-An(Ab-Or) diagrams. The roughly gradational modal variations of the phenocryst phases are shown upward within each rock unit. However, the contents and proportion of the phenocrysts in the Yangsan Tuff and the Hwajeri Formation represent the zigzaggedly undulatory variations. The continuous mineralogical gradients without large gaps define a large zoned magma system in the pre-eruptive, later precollapse and postcollapse magma chambers respectively. The zigzagged variations reflect the intermittent eruptive pulses representing any time gaps.

• Journal of Distribution Research
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• v.10 no.3
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• pp.1-14
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• 2005

It is important to control performance and a Sustainable Collaboration (SC) for the successful Supply Chain Management (SCM). This research developed a control model which analyzed SCM performances based on a Balanced Scorecard (ESC) and an SC using Support Vector Machine (SVM). 108 specialists of an SCM completed the questionnaires. We analyzed experimental data set using SVM. This research compared the forecasting accuracy of an SCMSC through four types of SVM kernels: (1) linear, (2) polynomial (3) Radial Basis Function (REF), and (4) sigmoid kernel (linear > RBF > Sigmoid > Polynomial). Then, this study compares the prediction performance of SVM linear kernel with Artificial Neural Network. (ANN). The research findings show that using SVM linear kernel to forecast an SCMSC is the most outstanding. Thus SVM linear kernel provides a promising alternative to an SC control level. A company which pursues an SCM can use the information of an SC in the SVM model.

• Investigative Magnetic Resonance Imaging
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• v.4 no.1
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• pp.7-13
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• 2000

Purpose : To assess the distortion of MRI with the Leksell stereotactic radiosurgery system in variable pulse sequence and imaging plane through phantom study, to find most adequate imaging plane and pulse sequence for stereotactic radiosurgery system. Materials and methods : We made the phantoms for MRI and get images in variable conditions and analyzed the image distortion using image analysis program, and statistically using paired student t-test. Results : The transeverse plane images had acceptable error ranges bless than 1.5mm) in all pulse sequence in both the analysis of fiducial marker in stereotactic G-frame and the phantom study. The coronal plane images had unacceptable large errors (more than 1.7mm) in the analysis of fiducial marker in the stereotactic G-frame, but had corrected small errors (less than 1.5mm) in the phantom study. Conclusion : We find from the phantom study that the present MR machines are adequate for stereotactic surgery system in frequently used pulse sequences, and imaging planes.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2003.04a
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• pp.35-35
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• 2003

)를 금속와이어에 인가하면 저항발열에 의해 와이어가 미세한 입자나 금속증기상태로 폭발하는 현상을 이용한 것으로 기상합성법에 속한다고 할 수 있다. 선폭법은 다른 제조법에 비해 공정이 간단하여 생산비용이 저렴하며, 원재료의 조성을 갖는 분말의 합성과 금속간화합물, 융점차이가 나는 재료의 합금화 등이 가능하다. 인가에너지의 크기와 폭발 시 분위기를 제어함으로써 분말의 평균크기와 분포 제어 또한 가능하다. 본 연구는 러시아의 우수한 기초기술을 바탕으로 Pb-Sn계 합금은 전기폭발법으로 극미세분말을 제조하였으며, 분말의 형상, 상 화학조성의 변화를 조사하였다. 본 실험에 사용된 Sn-Pb계(All-Union State Standard 1499-70, 0.53mm)합금와이어는 자동시스템(1-0.6Hz)에 의해 챔버안으로 공급되었다. 이 때 임계폭발 와이어 길이는 50-80nm으로 실험을 행하였다. 챔버 압력은 1.4~2.0atm으로 유지하였다. 제조된 분말의 특성은 XRD, XRPES, SEM등을 이용하여 분말의 형상과 상, 화학조성, 표면분석을 행하였으며 DSC, TGA, BET분석을 통하여 온도변화에 따른 금속분말의 열량변화, 질량변화, 비표면적을 측정하였다. 제조된 Sn-Pb계 분말은 모두 평균 입도 117nm~220nm의 구형형상이었다. 이때 합금분말의 조성은 51.17~63.21 at%Sn, 35.47~46.37 at%Pb로 나타났다. 와이어에 인가되는 비에너지(W/Wc)가 감소된에 EK라 표면층의 Pb함량이 증가함을 보였다. 이는 와이어 내부 저항의 감소로 인한 공정시간의 지연과 Sn, Pb의 확산계수 차이에 의한 것으로 사료된다. 열분석 결과, Sn~Pb계 화합물의 융점은 167~$169^{\circ}C$로 관찰되었으며, $10^{\circ}C$/min로 $920^{\circ}C$까지 승은 하였을 때 17.1~18 wt%의 질량증가를 보였다.TEX>계 나노복합분말이 얻어짐을 알 수 있었다. 이 때 X션 회절피크의 line broadening으로부터 복합분말의 Fe 명균 결정립 크기는 24nm로 초미세 결정럽의 분말합금이었다. 포화자화값은 볼밀처리에 따라 점점 증가하여 MA 30시간에는 20.3emu/g로 포화됨을 알 수 있었다. 또한 보자력 Hc는 MA초기단계에 350e로 매우 낮으나 30시간 후에는 Hc값이 2600e로 매우 큰 값을 나타내었다. 이것은 환원반응결과 초기에 생성된 Fe의 결정립이 비교적 크고 결정결함이 적으나 볼밀처리를 30시간까지 행하면 Fe 결정렵의 미세화 빛 strain 증가로 magnetic hardening이 일어나기 때문인 것으로 사료된다.길이가 50, 30cm인 압출재를 제조하였다. 열간압출한 후의 미세조직을 광학현미경으로 압출방향에 평행한 방향과 수직방향으로 관찰하였고, 열간 압출재 이방성을 검토하기 위하여 X선 회절분석을 실실하여 결정방위를 확인하였다. 전기 비저항 및 Seebeck 계수 측정을 위하여 각각 2$\times$2$\times$10$mm^3$ 그리고 5$\times$5$\times$10TEX>$mm^3$ 크기의 시편을 준비하였다.준비하였다.전류를 구성하는 주요 입자의 에너지 영역(75~l13keV)에서 가장 높은(0.80) 상관계수를 기록했다. 넷째, 회복기 중에 일어나는 입자들의 유입은 자기폭풍의 지속시간을 연장시키는 경향을 보이며 큰 자기폭풍일수록 현저했다. 주상에서 관측된 이러한 특성은 서브스톰 확장기 활동이 자기폭풍의 발달과 밀접한 관계가 있음을 시사한다.se that were all low in two aspects, named "the Nonsignificant group". And the issues were high risk perception in general setting and lo

• Journal of Korean Society of Environmental Engineers
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• v.32 no.11
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• pp.1001-1010
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• 2010

The purpose of this study is to investigate the concentration levels of particle materials ($PM_{10}$, asbestos), gas materials ($CO_2$, CO, $NO_2$, HCHO, Rn, VOCs) and total suspended colony (TSC), and the correlations among these materials in indoor air quality of 54 multiple-use facilities and 15 public-use facilities of Gwangju. The highest mean concentration of $PM_{10}$ was $69.2\;{\mu}g/m^3$ at indoor parking place, followed by childcare facilities, large commercial building and subway station building. The highest mean concentration of CO was 2.7 ppm at indoor parking place and that of $CO_2$ was 604.1 ppm at medical service facilities. The highest mean concentration of $NO_2$ was 0.036 ppm at indoor parking place. The geomean concentration of HCHO was $3.6\;{\mu}g/m^3$ in all facilities and the highest was $631.8\;{\mu}g/m^3$ at art gallery. The geomean concentration of VOCs (5 species) was $24.14\;{\mu}g/m^3$ in all facilities and toluene was the highest material of $15.30\;{\mu}g/m^3$, followed by xylene, ethylbenzene, benzene and styrene. The highest mean concentration of TSC was $625.3\;CFU/m^3$ at jjimjilbang, followed by childcare facilities, medical service facilities and large commercial building. The highest of asbestos was 0.0072 each/cc at childcare facilities and that of radon was 1.41 pCi/L at art gallery. PM10 showed positive correlations to TSC with $R^2\0.5332$ by lognormal equation at childcare facilities. CO2 showed positive correlations to CO at childcare facilities and indoor parking place. Lognormal equation fitted to the VOCs data more than normal equation in all facilities.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.119-120
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• 2011

Kawazoe는 1997년 p-type TOS를 만들기 위해서는 3가지가 충족되어야 한다고 언급한바 있다. 첫 번째, 가시광영역에서 투명하기 위해서 cation의 d10s0이 가득 차야 한다. 가득 차지 않은 d10 shell은 광 흡수가 가능하여 투과도를 떨어뜨린다. N-type을 예로 들어 ZnO, TiO, In2O3가 각각 Zn2+, Ti4+, In3+가 되어 d shell을 가득 차게 만드는 것을 볼 수 있다. 두 번째, cation d10s0 shell은 산소의 2p shell과 overlap 되어야 한다. 이 valence band는 홀 전도를 더욱 좋게 한다. 예를 들어 Cu1+(3d), Ag1+(4d)가 해당한다. 세 번째로, 양이온과 산소간의 공유결합을 강하게 하기 위해서 결정학적 구조는 매우 중요하다. Delafossite 구조는 산소가 pseudo-tetrahedral 구조로서 공유결합에 유리하다. 이러한 환경은 O2- (2p6)을 형성하고 홀의 이동도를 증가시킨다. 예를 들어 Cu2O의 경우 앞의 2가지를 만족시키지만 광학적 특성에서 좋지 않다. 그 이유가 3번째 언급한 결정학적인 요인에 있다. 결정 계의 환경은 Cu2O를 따라가면서 3차원적인 연결을 2차원적으로 변형된 delafossite 구조에서는 quantum well이 형성되어 band gap이 커진다. 본 연구에서는 전기적 이방성을 가지고 있는 delafossite CuCrO2 상에서 우선배향을 일으키는 인자 중 기판을 변화시켜 실험을 진행하였다. 결과적으로 기판변화를 통해 우선배향조절이 가능하였으며 CuCrO2 박막을 시켰으며, 결정방향에 따른 전기적 물성의 이방성에 관한 연구는 계속 진행 중에 있다. c-plane sapphire 기판위에는 [00l]로 성장하는 반면, c-plane STO 기판 위에는 [015] 방향으로 성장하는 것을 확인하였다. 이러한 원인은 기판과 증착되는 박막간의 mismatch를 최소화 하여 strain을 줄이고, 계면에서의 Broken boning 수를 줄여 계면에너지를 낮추는 방법이기 때문일 것으로 예상된다. C-plane sapphire 기판위에 증착될 경우 증착온도가 증가함에 따라 c-축으로의 성장이 온전해지며 이에 따라 캐리어농도의 감소와 모빌리티의 증가가 급격하게 변하는 것을 확인할 수 있다. 반면 c-plane STO 기판에서는 증착온도에 따른 박막의 배향변화가 없으며 전기적 물성 변화 또한 비교적 작은 것을 간접적으로 확인하였다.