• 천문학회보
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• 제39권2호
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• pp.119.2-119.2
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• 2014

Many astrophysical phenomena involve processes of magnetohydrodynamics (MHD) and relativistic magnetohydrodynamics (RMHD). A number of numerical schemes have been developed to solve the equations of ideal MHD and RMHD. Recent codes are based on upwind schemes which solve hyperbolic systems of equations following the characteristics of the systems. Upwind schemes stand out by their robustness, clarity of the underlying physical model, and ability of achieving high resolution. We present MHD and RMHD codes based on the total variation diminishing (TVD) and weighted essentially non-oscillatory (WENO) schemes, which are second and higher order accurate extensions of upwind schemes. We demonstrate the ability and limitation of codes based on upwind schemes through a series of tests.

• 한국임상약학회지
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• 제26권4호
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• pp.269-282
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• 2016

Venous thromboembolism, encompassing deep vein thrombosis and pulmonary embolism, has increased in cancer patients and adversely affects their prognosis. Low-molecular-weight heparins are recommended as efficacious and safe anticoagulation treatment in cancer patients. However, in practice, oral anticoagulation is preferred, especially if longterm or extended treatment is necessary. Novel oral anticoagulants have recently emerged as an alternative to the standard therapy owing to the ease of administration, predictable anticoagulation effect without the need of laboratory monitoring, and fewer drug interactions. These new agents have been shown as effective and safe for the management of cancer-associated thrombosis in ongoing head-to-head comparative trials. Here we review the advances and limitation of current anticoagulant therapies.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.218-221
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• 2006

The past Korean Bridge Design Specifications have no limitation on the amount of lap splices of longitudinal bars in the plastic hinge zone of piers. A majority of bridge piers which have been non-seismically designed might have some lap splices in plastic hinge zone. Also a number of those piers in Korea have a low aspect ratio(height/section area). So, some problems such as low ductility behavior may happen. In this study, the real pier which was non-seismically designed and has a low aspect ratio was selected for the quasi-static tests. Two groups of full scaled RC pier models of which aspect ratios are about 2.26 and about 2.67 were fabricated. And then, quasi-static tests according to the drift level history method were implemented. From the test results, the failure of these test specimens have been shown in the complex shear-flexural or shear modes. The low aspect ratio and the lap splice have largely influenced on the seismic performance of bridge piers.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.461-462
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• 2009

2002년 Chopra에 의해서 Modal Pushover Analysis가 소개된 이후로, 성능기반내진설계법은 믿을수 있는, 새로운 형식의 내진설계법으로 관심을 받고 있다. 이 방법은 건축물 설계에 적용하는 연구는 많이 진행되었으나, 교량구조물의 경우, 1차모드가 지배적이지 않은 구조물의 특성상 이용에 제약이 있었다. 본 논문은 이런상황을 고려하여, 사장교에 성능기반내진설계법을 제안, 사용성에 대하여 작성하였다.

• 한국해양공학회지
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• 제19권4호
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• pp.21-27
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• 2005

Large welded structures, including ships and offshore structures, are normally in operation under cyclic fatigue loadings. These structures include many geometric discontinuities, as well as material discontinuities due to weld joints. The fatigue strength at these hot spots is very important for the structural performance. In the past, various Non Destructive Evaluation (NDE) techniques have been developed to detect fatigue cracks and to estimate their location and size. However, an important limitation of most of the existing NDE methods is that they are off line; the normal operation of the structure has to be interrupted, and the device often has to be disassembled. This study explores the development of a structural health monitoring system, with a special interest in applying the technique to welded structural members in ship and offshore structures. In particular, the impedance based structural health monitoring technique that employs the coupling effect of piezoceramic (PZT) materials and structures is investigated.

• 대한가정학회지
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• 제38권1호
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• pp.185-198
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• 2000

Recently, many researchers have been interested in attachment processes in adolescence. However, the nature of attachment formation and transfer during this developmental period were not answered yet. This study examine the mechanism of attachment transfer from parents to friends, and the effects of childhood attachment styles on the level of attachment transfer and loneliness in adolescence. The resets show the majority of participants(70%) used their parents as primary attachment figures but were in the process of transferring attachment-related functions from parents to peers. There were the significant effects of attachment style, the level of transfer or state and trait loneliness in adolescence. This study provide the implications and limitation for conceptualization and measurement of adolescent attachment formation and loneliness.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2010년도 춘계 학술논문 발표대회 1부
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• pp.179-183
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• 2010

The safety accident is one of the formidable issues in construction field, and in order to prevent safety accident, contractors perform safety education, safety control document, meeting with labors, and safety instruction in construction phase. However, safety accident is occurred continuously, it is needed to analyze which factors are affected to safety accident. day of the week, daily construction cost, and daily work task were selected as those factors. The result in this research represented that those factors were not considered as an critical one in safety accident. Because of approach limitation to safety accident, only two case studies were collected. If more safety accident cases are gathered in future study, it will clarify the cause of safety accident and will prevent safety accident.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.334-337
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• 2000

Extracellular polysaccharide was produced by Pseudomonas elodea NK-2000 under nitrogen limitation and aerobic condition, The effect of agiatation speed on cell growth and production of exopolymer was investigated. The agitation speed of 7.5 L fermentor ranged from 200 to 500 rpm. Production of exopolymer increased with higher agitation speed. Maximal cell growth and production of exopolymer from 2% glucose were 3.35 g/l and 3.80 g/l, respectively when agitation speed was 400 rpm.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.196-197
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• 2014

Low carbon construction is an important operation management goal such as cost, time, and quality in construction community. This paper introduces a system which measures the variability of carbon dioxide amounts. First, this system allows creating construction operation models of which the level of detail is breakdown into the work task level. Second, the system implements sensitivity analysis along with a ranges of resources that are allocated in an operation model. It facilitates to find the optimal resource combination using the operation performances such as the amount of emissions, operation completion time, and cost. Lastly, it identifies the best fit probability distribution functions of performance criteria given a certain resource combination. It allows project manager to query the percentages to complete the operation within a limitation specified by the system users.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.298-299
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• 2014

As a governmental plan for real estate revitalization, remodeling vertical extension has been permitted. Thus, the Ministry of Land, Infrastructure and Transport preannounced proclaiming the revised Housing Act and establishing the remodeling basic plan, and it is anticipated that the remodeling market will be revitalized in earnest after the enforcement of remodeling vertical extension(April 25th. 2014). As vertical extension is applicable up to 3 stories, the safety of building for remodeling is becoming important, so most remodeling construction works use various methods for structural reinforcement. In this process, the selection of structural reinforcement method has depended on structural engineer's experience and knowledge and there has been a limitation in selecting the optimum structural reinforcement method which considers remodeling project characteristics. Therefore, this study analyzed the factors to determine the kinds of structural reinforcement method in a remodeling project and suggested a process to select the best structural reinforcement method of remodeling construction.