• Structural Engineering and Mechanics
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• 제86권6호
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• pp.715-730
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• 2023

Broad studies have addressed the issue of structural element damage identification, however, rubber bearing, as a key component of load transmission between the superstructure and substructure, is essential to the operational safety of a bridge, which should be paid more attention to its health condition. However, regarding the limitations of the traditional bearing damage detection methods as well as few studies have been conducted on this topic, in this paper, inspired by the model updating-based structural damage identification, a two-stage bearing damage identification method has been proposed. In the first stage, we deduce a novel bearing damage localization indicator, called element relative MSE, to accurately determine the bearing damage location. In the second one, the prior knowledge of bearing damage localization is combined with sailfish optimization (SFO) to perform the bearing damage estimation. In order to validate the feasibility, a numerical example of a 5-span continuous beam is introduced, also the noise robustness has been investigated. Meanwhile, the effectiveness and engineering applicability are further verified based on an experimental simply supported beam and actual engineering of the I-40 Bridge. The obtained results are good, which indicate that the proposed method is not only suitable for simple structures but also can accurately locate the bearing damage site and identify its severity for complex structure. To summarize, the proposed method provides a good guideline for the issue of bridge bearing detection, which could be used to reduce the difficulty of the traditional bearing failure detection approach, further saving labor costs and economic expenses.

• 한국위험물학회지
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• 제2권1호
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• pp.12-17
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• 2014

With a rapid growth of domestic industry in korea, now about 25,000 kinds of chemicals are being distributed, and it has been known that just about 15% of them has toxic substances. Recently, South Koreans have an anxiety about the stability and accidents of chemicals because chemical accidents like Gumi hydrofluoric acid accident have occurred. The U.S. has adopted the systems like EPCRA (Emergency Planning and Community Right-to-Know Act), TRI (Toxic Release Inventory) and TSCA (Toxic Substances Control Act), and is also managing the hazardous chemicals by providing the information about them to its people and site workers. Japan's Ministry of Health, Labor and Welfare also has adopted J-CHECK system and is implementing it to let Japanese people know the information of safety of chemicals about REACH. However, the Korean government has a difficult situation to mediate the different idea with the Korean industry to make lower statute of Pre-legislation registration & evaluation of chemicals that will be implemented and Chemical Material Control Association that is being implemented. Especially city and country areas located in the industrial areas need political improvement focusing on vulnerable area through the check about current situation of hazardous chemicals of jurisdiction and management method, but the information about the management situation of small scale work places is insufficient. Therefore this study set up the urgent management area in Ansan Smart Hub through NFPA code according to the types of accident and dander characteristics of each chemical being used in the companies that have less than 50 workers and deal with chemicals located in Ansan Smart Hub in Gyeonggi-do.

• 한국지반공학회논문집
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• 제31권5호
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• pp.5-21
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• 2015

에너지파일이란 새로운 형식의 지중열교환기로서, 건물의 기초 구조물인 말뚝 내부에 열교환 파이프를 삽입하고 파이프 내부로 유체를 순환시켜 지반과 말뚝 매질사이의 열교환을 유도한다. 에너지파일은 기존의 기초 구조물을 활용하여, 구조물의 지지 기능과 지중열교환기로서의 기능을 동시에 수행하는 에너지 구조체이다. 본 연구에서는 에너지파일의 실증연구를 위하여 총 6가지 형태의 열교환 파이프가 삽입된 실규모 현장타설 에너지파일을 시험 시공하였다. 열교환 파이프의 형태는 다양한 형태별 성능 및 시공성 비교를 위해 병렬 U형 3본(5쌍, 8쌍, 10쌍), 코일형 2본(피치간격 200mm와 500mm), S형 1본으로 선정하였다. 총 6가지 형태의 열교환 파이프를 시공하면서 시공 소요시간, 인력 소요, 필요 부대시설, 특이사항 등을 정리하여 각 형태별 시공성을 평가하였다. 또한 시공된 현장타설 에너지파일에 대한 열교환 성능 평가시험을 수행하였다. 열교환 성능 평가시험은 실제 상업 건물의 냉방 부하를 모사하기 위하여 8시간 가동 16시간 휴지의 간헐적 가동을 통하여 수행하였다. 열교환 성능 평가시험 결과를 통하여 각 현장타설 에너지파일의 열교환량을 산정하였으며, 이를 에너지파일 근입 깊이 및 열교환 파이프 길이로 정규화하여 각 형태별 열교환 효율을 평가하였다. 마지막으로 현장타설 에너지파일의 경제성을 분석하기 위하여 각 형태별 에너지파일의 시공비와 에너지파일 단위 길이 당 열교환 성능을 통해 1W/m 당 소요 비용을 산정하였다.

• Steel and Composite Structures
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• 제21권1호
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• pp.73-91
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• 2016

The use of box columns has been increased due to the rigidity in rigid orthogonal moment resisting frames. On the other hand, the installation and welding of necessary horizontal continuity plates inside the columns are both labor-consuming and costly tasks. Accordingly, in this paper, a new beam-to-box column connection by trapezoidal external stiffeners and horizontal bar mats is presented to provide seismic parameters. The proposed connection consists of eight external stiffeners in the level of beam flanges and five horizontal bar mats in Concrete Filled Tube (CFT) columns. The new connection effectively alleviates the stress concentration and moves the plastic hinge away from the column face by horizontal external stiffeners. In addition, the result shows that proposed connection has provided the required strength and rigidity of connection, so that the increased strength, 8.08% and rigidity, 3.01% are compared to connection with internal continuity plates, also the results indicate that this connection can offer appropriate ductility and energy dissipation capacity for its potential application in moment resisting frames in seismic region. As a result, the proposed connection can be a good alternative for connection with continuity plates.

• 조명전기설비학회논문지
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• 제15권5호
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• pp.1-7
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• 2001

조명시스템의 경제성에 크게 영향을 주는 요소들을 보면 초기 설비비, 보수비, 전기요금 등이 있다. 이 중에서 보수비는 램프 교환비, 램프교환 인건비, 청소비로 구성되어 있으므로 부소계획에 따라서 조명시스템의 경제성이 다르게 나타난다. 따라서 설계초기에 어떠한 조명시스템이 경제적으로 유리한가를 예측하는 것은 중요하다. 그러므로 본 연구에서는 평균조도를 계산하는데 사용되는 ZCM에서의 보수율 구성 요소들을 변화시켜 보수율을 산정한 다음 조명시스템의 경제성을 평가하여 보수율의 중요성을 보였다.

• Current Research on Agriculture and Life Sciences
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• 제3권
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• pp.55-61
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• 1985

양계 및 양돈용 배합사료중 pellet 사료와 분말사료의 생산비를 비교하였다. 비교분석을 위하여 박(1982)이 개발한 모형을 이용하였으며 공장의 규모는 일산 80ton으로부터 400ton이었다. 분석된 결과를 요약하면 다음과 같다. 1. 동력비는 pellet 사료가 분말사료에 비해 4배가 높았다. 2. 노동비는 pellet 사료가 분말사료에 비해 20%가 높았다. 3. 일산 200ton 규모의 경우 투자비용은 pellet 사료가 20% 높았다. 4. 고정비 및 변동비를 고려한 총생산비를 공장규모가 100ton에서 400ton으로 커질 경우 pellet 사료가 분말사료에 비해 30%에서 50%로 증가되었다.

• Asian Journal of Business Environment
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• 제10권2호
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• pp.17-21
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• 2020

Purpose: This paper explores diverse issues related to the problem of women's unpaid domestic care work, and as a factor of gender inequality in their professional practice. Research Design: This article concentrated only on the analysis of secondary data available on the topic along with observation of facts in Kazakhstan based on diverse sources. In current conditions, the problem of women's unpaid domestic care work, and consequently, the lack of enough time and energy for professional employment. Distinguish domestic work vs. job/career/occupation, self-fulfillment, education, and leisure has a significant impact on women's life satisfaction. Data, and Methodology: This article focuses only on secondary data available in different sources from which the researchers procures comprehensive data and information. Results and conclusion: A family policy that aims to promote combining maternity, and domestic work with paid employment is an effective way to increase the proportion of working mothers/women. It is crucial to not only proportionally distribute the household responsibilities in the family but also to form an effective mechanism of state support for women through the development of the social services sector, as well as the adoption of a system-wide approach to gender equality.

• 혜화의학회지
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• 제8권2호
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• pp.133-152
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• 2000

1. At the Menstruation Period, the uterus is easy to be invaded by a toxin because of its patency. Take cleanliness and hygiene into consideration. 2. At the Menstruation Period, much attention must be paid at the regulation of coldness and heat to harmonize the Menstruation. 3. At the Menstruation Period, excessive exercise must be avoided. Appropriate labor can help the circulation of vital energy & blood and reinforce the immunity of body. 4. The nourishing, plain, warming, digestible food is good at the Menstruation Period. Hot, stenched, stimulating food must be avoided and nuts & water fruit must not be overeaten. 5. At the Menstruation Period, sharpness & excessiveness of emotion must be avoided and a comfortable mood must be maintained. Especially premenstrual or postmenstrual period, peaceful spirit and sufficient sleep must be kept. 6. Women generally feel uncomfortable at the Menstruation Period, but it disappears spontaneously after menstruation. Don't take an overdose of medicine because it can disturb the normal condition.

• 설비공학논문집
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• 제20권3호
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• pp.167-174
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• 2008

Cost related to building equipment accounts for about 85% of the life cycle cost of buildings. Therefore proper selection of air-conditioning system is important for reducing the overall cost of buildings. In this study, medium capacity EHP and GHP for air-conditioning a building with a floor area of 1,200 $m^2$ are compared economically. To consider all the factors of initial and operation costs effectively, an annual equal payment method is proposed. For the initial cost, cost of equipment, construction, installation, electric facility, financial subsidy and tax cut is considered. Cost of basic electricity, energy(electricity and gas), space charge, labor, insurance and repair is considered for the operation cost. Under the assumptions made in this study, overall cost of EHP is less than that of GHP, but this is not absolute and different outcome may result if different assumptions are made. This study is useful for those who are interested in choosing an air-conditioning system that costs less for mid-size buildings with simple calculations.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1998년도 춘계학술대회논문집
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• pp.138-143
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• 1998

The continuous casting process has been adopted increasingly in recent years to save both energy and labor. It has experienced a rapid development in the production of semi-finished steel products, replacing the conventional route of ingot casting plus rolling. To achieve this good merit, however, more studies about a heat transfer mechanism between roll and slab are needed. So this paper shows the results of the deformation behavior of steel cast slabs, which are about the solidification and heat transfer. This study is used to prevent internal cracks of a slab in a bending and unbending zone. The value of moving strand shell bulging between two supporting rollers under ferrostatic pressure and slab-self weight has been computed in terms of creep and elastic-plasticity. The high strand distributions in solidified shell undergoes a series of bulging are calculated with boundary condition a very closed to continuous steel cast slabs productions.