• Title/Summary/Keyword: improved ground

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Development of a Rule-based BIM Tool Supporting Free-form Building Integrated Photovoltaic Design (비정형 건물일체형 태양광 발전 시스템 규칙기반 BIM설계 지원 도구 개발)

  • Hong, Sung-Moon;Kim, Dae-Sung;Kim, Min-Cheol;Kim, Ju-Hyung
    • Journal of KIBIM
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    • v.5 no.4
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    • pp.53-62
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    • 2015
  • Korea has been at the forefront of green growth initiatives. In 2008, the government declared the new vision toward 'low-carbon society and green growth'. The government subsidies and Feed-in Tariff (FIT) increased domestic usage of solar power by supplying photovoltaic housing and photovoltaic generation systems. Since 2000, solar power industry has been the world's fastest growing source with the annual growth rate of 52.5%. Especially, BIPV(Building Integrated Photovoltaic) systems are capturing a growing portion of the renewable energy market due to several reasons. BIPV consists of photovoltaic cells and modules integrated into the building envelope such as a roof or facades. By avoiding the cost of conventional materials, the incremental cost of photovoltaics is reduced and its life-cycle cost is improved. When it comes to atypical building, numerous problems occur because PV modules are flat, stationary, and have its orientation determined by building surface. However, previous studies mainly focused on improving installations of solar PV technologies on ground and rooftop photovoltaic array and developing prediction model to estimate the amount of produced electricity. Consequently, this paper discusses the problem during a planning and design stage of BIPV systems and suggests the method to select optimal design of the systems by applying the national strategy and economic policies. Furthermore, the paper aims to develop BIM tool based on the engineering knowledge from experts in order for non-specialists to design photovoltaic generation systems easily.

Integrating GPS/INS/PL for Robust Positioning: The Challenging Issues

  • Wang, Jinling;Babu, Ravindra;Li, Di;Chan, Franics;Choi, Jin-Ho
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.127-132
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    • 2006
  • The Global Positioning System (GPS), Inertial Navigation System (INS) and Pseudolite (PL) technologies all play very important roles in navigation systems. As an independent navigation system, GPS can provide high precision positioning results which are independent of time. However, the performance will become unreliable when the system experiences high dynamics, or when the receiver is exposed to jamming or RF interference. In comparison to GPS, though INS is autonomous and provides good short-term accuracy, its use as a standalone navigation system is limited due to the time-dependent growth of the inertial sensor errors. PLs are ground-based transmitters that can transmit GPS-like signals. They have some advantages in that their positions can be determined precisely, and the Signal-to-Noise Ratios (SNR) are relatively high. Because their combined performance, in principle, overcomes the shortcomings of the individual systems, the integration of GPS, INS and PL is increasingly receiving attention from researchers. Depending on the desired performance vs complexity, system integration can be carried out at different levels, namely loose, tight and ultra-tight coupling. Compared with loose and tight integration, although it is more complex in terms of system design, ultra-tight integration will be the basis of the next generation of reliable and robust navigation systems. Its main advantages include improved performance under exposure to high dynamics, and jamming and RF interference mitigation. This paper presents an overview of the ultra-tight integration developments and discusses some of the challenging issues.

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Adaptive weight approach for stereo matching (적응적 가중치를 이용한 스테레오 정합 기법)

  • Yoon, Hee-Joo;Hwang, Young-Chul;Cha, Eui-Young
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.08a
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    • pp.73-76
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    • 2008
  • We present a area-based method for stereo matching using varying weights. A central problem in a area-based stereo matching is different result from selecting a window size. Most of the previous window-based methods iteratively update windows. However, the iterative methods very sensitive the initial disparity estimation and are computationally expensive. To resolve this problem, we proposed a new function to assign weights to pixels using features. To begin with, we extract features in a given stereo images based on edge. We adjust the weights of the pixels in a given window based on correlation of the stereo images. Then, we match pixels in a given window between the reference and target images of a stereo pair. The proposed method is compared to existing matching strategies using both synthetic and real images. The experimental results show the improved accuracy of the proposed method.

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Back Analysis for the Properties of Cut and Cover Tunnel using Optimization Algorithms (최적화 알고리즘을 이용한 복개터널 물성값의 역해석)

  • Park, Byung-Soo;Jun, Sang-Hyun
    • Journal of the Korean Society of Hazard Mitigation
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    • v.8 no.1
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    • pp.81-87
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    • 2008
  • This study is about the back analysis to optimize the uncertain parameters of geotechnical properties used in stability analysis of cut and cover tunnel. The Simplex algorithm, Powell algorithm, Rosenbrock algorithm, and Levenberg-Marquardt algorithm are applied for artificial problems of ground excavation. Furthermore, results are compared in the matter of the reliability of optimal solutions with a certain accuracy and the computation speed for evaluations of variables. As shown in results of numerical analysis, all of four algorithms are converged to exact solution satisfying the allowable criteria. And Levenberg-Marquardt's and Rosenbrock's algorithms are identified to be the more efficient methods in the evaluations of functions. After the back analysis for Poisson ratio and Young's modulus for cut and cover tunnel has been performed, design parameters have been correctly estimated and computation time has been improved while the number of measure points is increased.

A Study on Interior Design Expressional Tendency of Korean style Apartments introducing Traditional Hanok Factors - Focusing on the Cases applied to Korean Brand-name Apartments - (한옥의 전통적 요소를 도입한 한국형 아파트 실내디자인의 표현 경향에 관한 연구 - 한국 브랜드 아파트에 적용된 사례를 중심으로 -)

  • Lim, Bo-Ra;Choi, Sang-Hun
    • Korean Institute of Interior Design Journal
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    • v.25 no.3
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    • pp.121-128
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    • 2016
  • Focusing on the cases applied to korean brand-name apartments In 1960s, economical growth and introduction of western-type cultures led to a boom of apartment construction. After internationalization'in 1980s through Olympic games in 1988, korean culture has attracted attention and individual life quality has been improved. Since 1990s, changes in personal life style has affected the housing culture and the construction companies started moving from quantitative supply to developing their own differential characteristics. Differentiation scheme triggered by construction companies since mid-1990s mainly focused on various ideas for space deployment. Space plans include such things as a private ground, a kitchen in the south, etc. while interior plans include to provide selection of the korean traditional style, natural or casual one. 'korean traditional style' apartment is one of such theme of the brand-named apartment. Interests on 'Tradition' can be broken down into a social trend and media trend. Firstly, the former includes the designation of Bukchon as a reserving area, one of the governmental 'Hanok Survival Program', and traditional building promotion scheme on the basis of construction policy plans. Secondly, the latter covers the interests which attract through the media showing oriental cosmetics, korean culture export via Hallyu, popularity of korean dramas, etc. Thus, it seems worth studying on the apartments with traditional factors. And also, this study aims to setup the concept and trends of korean traditional style apartments through the interior expression on the korean-factor space developed by brand-name apartments so that it could correct such false knowledge out of misunderstood concept of traditional space which results from simple decoration or structure type not accompanying Korean emotion or spirit rendered by some misleading media.

A Study on the Improvement of Passenger Ship's Operational Environments in Wan-do Area (완도권 여객선 운항 환경 개선에 관한 연구)

  • Im, Nam-Kyun;Lee, Sang-Min;Seong, Yu-Chang
    • Journal of Navigation and Port Research
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    • v.37 no.6
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    • pp.581-586
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    • 2013
  • The sea traffic volume in Southwest sea including Wando area have increased every year. However the improvement of the facilities for convenience and safety in port and sea was not enough to meet the increasing demand of traffic and passengers' need. This study dealt with the situations and status of passenger ship traffic system in Wando area. In addition to, questionnaire survey of passenger ship user in Wando area was carried out in order to research the improvement of marine traffic system. On the basis of the result, navigation risks in the area was analysed. The institutional system such as passenger ship fare, enhanced traffic system that can improve marine traffic environment in the area were suggested and examined. The urgent issue was the scattered fishing ground near fairway which makes narrow passage and can cause risky passeger ship's navigation. In the side of passeger ship's operation, the wage of cargo handling was relatively expensive that needed to be improved.

Improvement of Land Cover / Land Use Classification by Combination of Optical and Microwave Remote Sensing Data

  • Duong, Nguyen Dinh
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.426-428
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    • 2003
  • Optical and microwave remote sensing data have been widely used in land cover and land use classification. Thanks to the spectral absorption characteristics of ground object in visible and near infrared region, optical data enables to extract different land cover types according to their material composition like water body, vegetation cover or bare land. On the other hand, microwave sensor receives backscatter radiance which contains information on surface roughness, object density and their 3-D structure that are very important complementary information to interpret land use and land cover. Separate use of these data have brought many successful results in practice. However, the accuracy of the land use / land cover established by this methodology still has some problems. One of the way to improve accuracy of the land use / land cover classification is just combination of both optical and microwave data in analysis. In this paper for the research, the author used LANDSAT TM scene 127/45 acquired on October 21, 1992, JERS-1 SAR scene 119/265 acquired on October 27, 1992 and aerial photographs taken on October 21, 1992. The study area has been selected in Hanoi City and surrounding area, Vietnam. This is a flat agricultural area with various land use types as water rice, secondary crops like maize, cassava, vegetables cultivation as cucumber, tomato etc. mixed with human settlement and some manufacture facilities as brick and ceramic factories. The use of only optical or microwave data could result in misclassification among some land use features as settlement and vegetables cultivation using frame stages. By combination of multitemporal JERS-1 SAR and TM data these errors have been eliminated so that accuracy of the final land use / land cover map has been improved. The paper describes a methodology for data combination and presents results achieved by the proposed approach.

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Long-term Results of the Carpentier-Edwards Porcine Valve (Carpentier-Edwards 판막의 장기 술후성적)

  • Kim, Jong-Hwan;Lee, Yeong-Gyun
    • Journal of Chest Surgery
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    • v.19 no.1
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    • pp.83-91
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    • 1986
  • The Carpentier-Edwards porcine xenograft valve was used in 21 patients at Seoul National University Hospital during the period between 1977 and 1979. Twenty-four Carpentier-Edwards valves were implanted along with 2 others. Three patients died within 30 days of operation, an operative mortality rate of 14.3%. Eighteen early survivors were followed up for a total 67.5 patient-years [mean, 45.0$\pm$32.0 months]. There were 2 late deaths with a linealized late mortality rate of 2.96%/patient-year; one died from cerebral bleeding [1.48% bleeding/patient-year] and the other from prosthetic valve endocarditis [1, 48% endocarditis/patient-year]. There was no case of thromboembolism. Two patients developed mitral regurgitation [2.96% failure/patient-year]. Symptomatic improvement was excellent. The actuarial survival rate and the probability of freedom from overall valve failure were 75.3$\pm$9.6% and 80.7$\pm$12.9% at 9 years after surgery respectively. During the period from October, 1968, through June, 1985, 1, 190 substitute heart valves were used in a total of 967 patients at Seoul National University Hospital; of which, 90.9% were either porcine aortic or bovine pericardial xenograft valves. For the evaluation of the xenograft tissue valves, the consecutive patients with lonescu-Shiley valve in the mitral, aortic and both positions, Angell-Shiley valve and Carpentier-Edwards valve were recently studied on the clinical ground. They were 531 patients, and 643 xenograft valves were used. The operative mortality rate was 6.97% and a linealized late mortality rate 2.94%/patient-year. A total of 490 early survivors were followed up for 917.6 patient-years [mean, 22.5 months], and 70% of patients completed the follow-up. The linealized incidences of complications were: 2.29% emboli/patient-year, 1.98% bleeding/patient-year, 1.20% endocarditis/patient-year, and 3.49% failure/patient-year. These clinical resutls are fully comparable with those in the major reports. The durability of the glutaraldehydepreserved xenograft heart valves remains as a great concern and a continuing debate, expecially for the group of patients in the pediatric age. The need of more durable material for the improved tissue valves was also discussed.

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Concept of the Encapsulation Process and Equipment for the Spent Fuel Disposal (심지층 처분을 위한 사용후핵연료 포장공정 장비개념 설정)

  • Lee J.Y.;Choi H.J.;Cho D.K.;Kim S.K.;Choi J.W.;Hahn P.S.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.10a
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    • pp.470-473
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    • 2005
  • Spent nuclear fuels are regarded as a high level radioactive waste and they will be disposed in a deep geological repository. To maintain the safety of the repository for hundreds of thousands of years, the spent fuels are encapsulated in a disposal canister and the canister containing spent fuels should have the structural integrity and the corrosion resistance below the several hundreds meters from the ground surface. In this study, the concept of the spent fuel encapsulation process and the process equipment fur deep geological disposal were established. To do this, the design requirements, such as the functions and the spent fuel accumulations, were reviewed. Also, the design principles and the bases were established. Based on the requirements and the bases, the encapsulation process and the equipment from spent fuel receiving process to transferring canister into the underground repository including hot cell processes was established. The established concept of the spent fuel encapsulation process and the process equipment will be improved continuously with the future studies. And this concept can be effectively used in implementing the reference repository system of our own case.

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Lipiodol-induced pneumonitis following transarterial chemoembolization for ruptured hepatocellular carcinoma (파열 간암의 간동맥 항암 화학색전술 후 발생한 유도 폐렴)

  • Kim, Haewon;Kim, Yong Hoon;Yoon, Hong Jin;Lee, Kwang Hoon;Joo, Seung Moon;Byun, Min Kwang;Lee, Jung Il;Lee, Kwan Sik;Kim, Ja Kyung
    • Journal of Yeungnam Medical Science
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    • v.31 no.2
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    • pp.117-121
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    • 2014
  • Transarterial chemoembolization (TACE) is a widely accepted nonsurgical modality used for the treatment of multinodular hepatocellular carcinoma (HCC). The careful selection of the candidate is important due to the risk of developing various side effects. Fever, nausea, abdominal pain, and liver enzyme elevation are commonly known side effects of TACE. Hepatic failure, ischemic cholecystitis, and cerebral embolism are also reported, although their incidence might be low. Pulmonary complication after TACE is rare, and the reported cases of lipiodol pneumonitis are even rarer. A 53-year-old man was treated with TACE for ruptured HCC associated with hepatitis B virus infection. On day 19 after the procedure, the patient complained of dyspnea and dry cough. Chest computed tomography showed diffuse ground glass opacities in the whole-lung fields, suggesting lipiodol-induced pneumonitis. After 2 weeks of conservative management, the clinical symptoms and radiologic abnormalities improved. Reported herein is the aforementioned case of lipiodol-induced pnemonitis after TACE, with literature review.