• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.64-65
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• 2016

According to the recent increase in the height of supertall buildings, construction lift became one of most important equipment for vertical transportation of resources. However, increase in lifting load during peak time in which the resources are concentrated often causes a risk of construction delay. This study suggests a concept of Double-Cage construction lift, which is a lift with two cages attached together allowing transportation of resources on two consecutive work floors simultaneously. The aim of this study is to present a simulation model suitable for calculating hoisting time of Double-Cage construction lift. The proposed model is expected to be utilized when applying Double-cage construction lift for its efficient operation and management.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.17-18
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• 2016

Today, many kind of buildings are higher than those of previous generations, and Curtain Wall is adapted broadly as an outer wall material. But weather and environmental condition could cause problems in curtain wall construction in most construction projects. High wind speed and unplanned lifting equipment's allocation could cause construction delay and cost increase. To solve these problems, we suggest using a curtain wall mullion as a rail to lift curtain wall which is less affected wind speed. And we would like to show a preliminary data of its economic advantage evaluation.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2004년도 유체기계 연구개발 발표회 논문집
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• pp.492-500
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• 2004

The purpose of this study is localization of safety relief valves fur Nuclear Service through technical development with overall design, fabrication, inspection, capacity certification test and functional qualification test of safety relief valves in accordance with KEPIC MN Code(or ASME Sec.III ). The safely relief valve is the important equipment used to protect the pressure vessel, the steam generator and the other pressure facility from overpressure by discharging the operating medium when the pressure of system is reaching the design pressure of the system. But we're depending on technology of the other country up to the present time. Because we don't have our own technologies, we have been spent the great time and money on installing and repairing safety relief valve at nuclear power plant. Therefore we have to achieve the development of safety relief valves for Nuclear Service with our own technologies.

• 대한안전경영과학회지
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• 제18권3호
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• pp.71-80
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• 2016

This study is on safety improvement measures through analysis of accident cases during plant storage tank construction. Storage tank is a general term for artificial ground facility constructed to store oil, water, gas, and other chemicals. Some companies have clustered storage tanks (tank farm). The construction methods vary according to the component and types of fluids. Because most of the construction procedures include lifting heavy weight materials using heavy construction equipment and are carried out at high places, storage tank construction contains more risk factors than normal aerial construction. Recently, major accidents such as storage tank collapse have occurred often, and cost many lives due to the characteristics of the structure. In this study we would like to analyze the cause of these accidents and propose measures to improve safety.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.136-137
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• 2015

Tilt-up construction is the method that the wall structures are fabricated horizontally on site and placed at specified location using heavy lifting equipment. Tilt-up method generally has several advantages, such as of productivity improvement, labor savings, shortened the construction period the and cost savings. In this study, Tilt-up method is used for wall construction of detached house. Result shores the substantial improvement on construction period. The use of Tilt-up method led construction period reduction of 20%.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2004년도 춘계학술대회 발표 논문집
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• pp.217-222
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• 2004

This paper focuses on lossy medical image compression methods for medical images that operate on two-dimensional(2D) integer wavelet transform. We offer an application of the Set Partitioning in Hierarchical Trees(SPIHT) algorithm to medical images, using a 2D wavelet decomposition and a 2D spatial dependence tree. The wavelet decomposition is accomplished with integer wavelet filters implemented with the lifting method, where careful scaling and truncations keep the integer precision small and the transform unitary. We have tested our encoder on medical images using different integer filters. Results show that our algorithm with certain filters performs as well and is sometimes better lossy coding using 2D integer wavelet transforms on medical images.

• Industrial Engineering and Management Systems
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• 제9권2호
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• pp.178-194
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• 2010

To improve the ship operation in automated container terminals, it is important to schedule different types of handling equipment to operate synchronously. For example, a vehicle with container receiving and lifting capabilities is used to transport containers from a storage yard to a vessel and vice versa, while a triple quay crane (QC) can handle up to three 40-ft containers simultaneously. This paper discusses the manner in which vehicles should be assigned to containers to support such multi-lifts of QCs by using information about the locations and times of deliveries. A mixed-integer programming model is introduced to optimally assign delivery tasks to vehicles. This model considers the constraint imposed by the limited buffer space under each QC. A procedure for converting buffer-space constraints into time window constraints and a heuristic algorithmfor overcoming the excessive computational time required for solving the mathematical model are suggested. A numerical experiment is conducted to compare the objective values and computational times of the heuristic algorithm with those of the optimizing method to evaluate the performance of the heuristic algorithm.

• 한국산학기술학회논문지
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• 제16권6호
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• pp.4267-4275
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• 2015

조립식 주택은 기존 RC공법과 달리 사전에 전체공사의 약 60-80%를 유닛모듈 형태로 공장 제작하고, 차량을 이용하여 현장까지 운반 후 각 모듈을 결속하여 시공한다. 조립식 주택은 공장제작을 통한 급속시공이 가능한 장점이 있지만, 모듈을 현장까지 운반하는 과정에서 모듈 탈락의 우려가 있으며, 이로 인한 모듈의 변형 및 외장재의 파손이 발생할 수 있다. 본 연구는 기존의 모듈운반 고정장치의 문제점을 분석하고 개선된 고정장치를 제안하였다. 고정장치 개선안을 도출하기 위해 고정장치에 가해지는 운반하중을 몬테카를로 시뮬레이션을 이용하여 분석하고, 비선형 유한요소 해석을 통한 구조적 성능을 검증하였다. 유닛모듈의 하중분포는 통계분석을 통해 3개 유사하중 그룹으로 구분되며, 극단값 분포(Extreme Value Distribution)와 가장 유사한 하중분포를 가진 것으로 분석되었다. 통계분석 및 몬테카를로 시뮬레이션을 통해, 운반하중의 최대값(28.9kN) 및 95% 신뢰도 범위 내 하중값(-1.22~9.5kN)을 계산하였다. 비선형 구조해석 결과는 본 연구에서 제시한 고정장치 개선안이 한계하중 35.3kN까지 파괴가 일어나지 않았으며, 95% 신뢰도 범위 내 하중에서도 충분히 견뎌내는 강성을 지니고 있음을 보여주고 있다.

• 대한인간공학회지
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• 제28권3호
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• pp.125-134
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• 2009

The muscle strengths in various postures are used in our daily life with or without our recognition. Also, many works are still performed with strengths, although mechanization and automation have been fairly accomplished at the industry site. Since the late seventies, various body measurements have been conducted periodically in Korea, however, muscle strengths have not been measured actively. For this reason, the muscle strength data have been hardly accumulated. The aims of this study are to learn more about the physical strength of young-aged Koreans and to provide basic information for designing equipments, tools and facilities in the work site and daily life. The muscle strengths that are related to shoulder and upper limbs joints, which are used frequently, are measured in this study. Eighteen muscle strengths, from seven different movements such as elbow flexion, elbow extension, shoulder abduction(seated), shoulder adduction(seated), shoulder rotation(internal and external), lifting a tray, and turning a key(inward and outward) were measured. For every movement, the muscle strengths for both hands were measured. In each measurement, five seconds averaged value and peak value were collected. Comparing the average value, the strength of shoulder adduction was the strongest for male and female, while strength of turning a key inward with left hand was the weakest for male and female. Strengths of preferred hand in elbow extension, shoulder abduction, shoulder external rotation, lifting a tray, and turning a key were stronger than those of non-preferred hand for both male and female. Rohrer's index considerably had an effect on muscle strength. The results of this study can provide some basic information not only in designing the equipment and facilities in work site or daily life, but also in selection, training and management of workers.

• 한국건축시공학회지
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• 제24권4호
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• pp.495-506
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• 2024

PC공동주택은 RC공사와 달리 양중장비에 의한 작업이 주공정으로 공기가 산정되기 때문에 PC벽체를 포함한 양중 단위공정분석이 선행되어야 한다. 본 연구는 Core, 내부, 외부 PC벽체의 조립공정을 분석하여 PC공동주택 기준층 공사 Cycle 분석하는 것이다. 각 PC벽체의 양중과정 및 시간을 도출하였고, 그 결과를 사례에 적용하여 기준층 골조공사의 양중 사이클을 분석하였다. 순수 부재설치 기간은 5일로 분석되었고, PC부재별 작업시간 비중은 Core PC벽체는 약 16%, 내부 PC벽체는 약 8%, 외부 PC벽체는 약 18%로 분석되었다. 본 연구의 결과는 PC벽체가 적용된 PC공동주택 골조공사 시공계획 시, 핵심자료로 활용될 것이다.