• Design & Manufacturing
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• 제6권1호
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• pp.79-83
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• 2012

Anti-theft safety caps for bolted joints are necessary to ensure the safety of citizens and prevent theft of manholes, bridge guardrails, bulletin boards, subway safety handrails and others. Safety caps enhance the look of bolted joints, avert accidents that involve hitting the head of bolts, hamper them from coming loose by covering the head of bolts. This study focuses on press die design methods and press molding condition setting to resolve bursting and cracks in products, and on molding material selection and heat treatment technologies to boost life extension.

• International Journal of Railway
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• 제5권2호
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• pp.84-88
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• 2012

Derailment due to wheel failure would cause a tremendous social and economical cost in service operation. It is necessary to evaluate quantitatively the safety with respect to high-speed train. Although the safety of railway wheel has been ensured by an regular inspection, all critical defects cannot be detected in inspection cycles and the wheel has been replaced because a defect quickly become critical for safety. Therefore, it is important to calculate quantitatively the fracture limit and remnant life of damaged railway wheel in wheel-rail system. In present paper, the critical crack size of wheel for high-speed train is simulated based on fracture scenario and the safety of wheel is evaluated.

• 한국안전학회지
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• 제10권2호
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• pp.120-128
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• 1995

The fatigue failure of rail is a principal source of derailment accidents. The reduction of fatigue failures can be achieved by Intensive track maintenance and periodic safety assessments for the railway. For the safety assessments, it is required to have more accurate knowledge for fatigue behavior such as the crack initiation, propagation, crack growth rate and the remaining service life in rail. In this paper, the mean stress effects for the fatigue behavior of rail steel are studied. For this study, the fatigue test is conducted and some equations for fatigue evaluation are applied and compared. From the results, we can see that the fatigue crack growth rate is the more increased as the men stress Is the more increased, the mean stress effect is represented well by the combination of stress intensity factor range and maximum stress intensity factor and Crooker and Range's equation represented by ${\Delta}K, K_{max}$ is the best fit for fatigue evaluation and safety assessment of rail.

• 한국안전학회지
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• 제24권5호
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• pp.48-56
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• 2009

This paper presents the procedure for the optimal design of a PSC-I girder bridge considering life cycle cost (LCC). The load carrying capacity curves for the concrete deck, PSC-I girder and $\pi$-type pier were derived and used for the estimate of service lives. Total life cycle cost for the service life was calculated as sum of initial cost, damage cost, maintenance cost, repair and rehabilitation cost, user cost, and disposal cost. The advanced First Order Second Moment method was used to estimate the damage cost. The optimization method was applied to the design of PSC-I girder bridge. The objective function was set to the annual cost, which is defined by dividing the total life cycle cost by the service life, and constraints were formulated on the basis of Korean Standards. The optimal design was performed for various service lives and the effects of design factors were investigated.

• 한국안전학회지
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• 제18권3호
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• pp.126-130
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• 2003

The term stress is currently used to cover a wide variety of phenomena, ranging from physical to social and cultural factors. The term has defined psychological stress as an imbalance between perceived or subjective demand and perceived response capability. The behavior science model has provided the accident proneness through the life change unit factors considering human behavior, life style, ideas, culture, and psychological state. Therefore, this paper presents the Korean life change unit model through statistical testing with the proposed life change unit factors on the unmarried workers living in the middle area. The proposed model can be simply used in real fields in order to minimize the industrial accidents.

• 대한안전경영과학회지
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• 제10권3호
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• pp.9-17
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• 2008

In today's industrial society, one observes fierce competition aiming at profit generation among companies, and the utilization of complex machineries and cutting edge science and technology constitutes a constant threat to the life, body, and health of employees. In such a context, it is precisely the purpose of the Industrial Safety and Health Act that is in force to provide protection to the life and health of employees against hazardous and harmful environment and the role of enterprises becomes more and more important in the law. The Industrial Safety and Health Act places the responsibility for preventing industrial accidents on the shoulders of the business employer by providing safety and health information relating to current employees and creating an appropriate work environment. The employer must recognize the importance of prevention of industrial accident and must possess a business philosophy that places top priority on safety when it comes to company management. In light of such practical considerations, the present study approaches to find out the influence of safety and health management on business management from a statistical sample survey point of view. By doing this, the study hopes to show that a through safety management serves to protect the life and health of employees and raise profit for businesses. What is more, the study hopes to demonstrate that promoting a sound business culture can act as fertilizer that promotes the ushering in of a bright society.

• Molecules and Cells
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• 제40권4호
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• pp.299-306
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• 2017

The transcriptional activator AphB has been implicated in acid resistance and pathogenesis in the food borne pathogens Vibrio vulnificus and Vibrio cholerae. To date, the full-length AphB crystal structure of V. cholerae has been determined and characterized by a tetrameric assembly of AphB consisting of a DNA binding domain and a regulatory domain (RD). Although acidic pH and low oxygen tension might be involved in the activation of AphB, it remains unknown which ligand or stimulus activates AphB at the molecular level. In this study, we determine the crystal structure of the AphB RD from V. vulnificus under aerobic conditions without modification at the conserved cysteine residue of the RD, even in the presence of the oxidizing agent cumene hydroperoxide. A cysteine to serine amino acid residue mutant RD protein further confirmed that the cysteine residue is not involved in sensing oxidative stress in vitro. Interestingly, an unidentified small molecule was observed in the inter-subdomain cavity in the RD when the crystal was incubated with cumene hydroperoxide molecules, suggesting a new ligand-binding site. In addition, we confirmed the role of AphB in acid tolerance by observing an aphB-dependent increase in cadC transcript level when V. vulnificus was exposed to acidic pH. Our study contributes to the understanding of the AphB molecular mechanism in the process of recognizing the host environment.

• 농약과학회지
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• 제11권4호
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• pp.222-229
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• 2007

천연기능성물질을 함유한 농산물을 활용하여 국민건강을 보호할 수 있는 방안을 모색하기 위해 항산화 및 항암 효과가 있는 것으로 알려진 양파를 이용하여 수컷 rat에서 농약독성 경감효과를 시험하였다. 6주간 양파즙액을 투여한 후 chlorprifos 0, 2, $4\;mg\;kg^{-1}$을 복강내 투여하였다. 간, 폐, 혈청 중 항산화효소인 SOD의 변화를 조사한 결과 양파즙액 투여 후 chlorprifos를 투여한 군이 chlorpyrifos 단독 투여군에 비해 간과 폐의 SOD 활성이 높게 나타나는 것으로 나타나 항산화기능이 증가함을 볼 수 있었다. 혈청 중 BUN/Creatinine ratio를 조사한 결과 양파즙액 투여 후 chlorpyrifos를 투여한 군이 단독 투여군에 비해 수치가 낮게 나타나 신장독성을 감소시킬 수 있을 것으로 판단된다.

• 한국어병학회지
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• 제27권1호
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• pp.67-75
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• 2014

Aquaculture drugs have used to prevent disease in aquaculture field for many years. In spite of many advantages, overdose and abuse may cause environmental pollutions and antibiotic resistances. Many countries try to protect the environment, biospecies and food safety. Recently, Korea enact laws and ordinances such as the Aquatic Animal Disease Control Act. The purpose of this act to contribute to the stable production and control system for aquatic diseases. The Maximum residue limits (MRLs) of aquaculture drugs have been established by Ministry of Food and Drug Safety (MFDS) and Drug licensing was in National Fisheries Research and Development Institute (NFRDI) by Aquatic Animal Disease Control Act. There is 750 items in aquaculture drugs and these are classified into 4 group, which is approval, necessary for prescription, unregulated and safety drug, and banned drug. MRLs of 30 items in aquaculture drug have been established by Food Sanitation Act. Future research is required to determine the suitable for abundant varied fishes of drugs for side effects and safety.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제19권3호
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• pp.7-19
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• 2013

Purpose: The main objective of this paper is, first, to assess a body of research evidence that articulates the impact of environmental and design factors on safety, quality of life, and health of the elderly who reside in geriatric hospitals or other elderly care facilities and, second, to draw out design implications that can be incorporated into design process and design decisions to help create healing environments for the elderly. Methods: Extensive literature review has been conducted to identify rigorous empirical studies that link the design of elderly care facilities to health-related outcomes and scrutinized peer-reviewed articles published in many different fields including architecture, psychology, nursing to gerontology. Results: The review found a growing body of rigorous studies that identified physical environmental and design factors that improve safety, quality of life, and health of the elderly in geriatric hospitals or other elderly care facilities. Implications: The findings of the review can be translated to design decisions to promote safety, quality of life, and health of the elderly in geriatric hospitals or other elderly care facilities.