• Journal of Microbiology and Biotechnology
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• 제29권3호
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• pp.392-400
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• 2019

Chondroitin, the precursor of chondroitin sulfate, which is an important polysaccharide, has drawn significant attention due to its applications in many fields. In the present study, a heterologous biosynthesis pathway of chondroitin was designed in a GRAS (generally recognized as safe) strain C. glutamicum. CgkfoC and CgkfoA genes with host codon preference were synthesized and driven by promoter Ptac, which was confirmed as a strong promoter via GFPuv reporter assessment. In a lactate dehydrogenase (ldh) deficient host, intracellular chondroitin titer increased from 0.25 to 0.88 g/l compared with that in a wild-type host. Moreover, precursor enhancement via overexpressing precursor synthesizing gene ugdA further improved chondroitin titers to 1.09 g/l. Chondroitin production reached 1.91 g/l with the engineered strain C. glutamicum ${\Delta}L-CgCAU$ in a 5-L fed-batch fermentation with a single distribution $M_w$ of 186 kDa. This work provides an alternative, safe and novel means of producing chondroitin for industrial applications.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.234-240
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• 2011

Preventing incidents occurred in construction process is important for safe implementation of construction projects. Due to the complexity and magnitude of the project and moreover, poor safe planning and management, construction incidents in Korea have been increasing. Reducing construction incidents effectively, appropriate safety management program in consideration of the incident rate of each facility is to be adapted. This study analyzes incident frequency and severity rate of each facility based on the data of construction sites(about 1,560 thousand cases) recorded by Korea Occupational Safety & Health Agency for 3 years from 2007 to 2009, and the incident related data (about 40 thousand cases) of Korea Workers' Compensation & Welfare Service. The results of this study revealed that construction incident rates of 'cold refrigeration storage facilities' are the highest among building types, followed by traditional building religious building, arcade department store and shopping center. In case of other facilities, the incident rate and the rate of intensity of 'pipelining project' are the highest, followed by 'tunneling project'. These results would be used in providing safety programs beneficial for preventing construction incidents.

• 한국산학기술학회논문지
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• 제12권6호
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• pp.2793-2800
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• 2011

본 연구에서는 범용 이동정보통신기기인 스마트폰을 플랫폼으로 하는 차선이탈경보 애플리케이션을 개발하고 최적화하였다. 최근 안전주행지원 솔루션 중 하나인 차선이탈경보시스템이 상용화되고 있지만, 고성능의 전용 플랫폼을 필요로 하기 때문에 시장에 쉽게 진입하지 못하고 있다. 본 연구에서는 스마트폰인 iPhone 3GS를 플랫폼으로 하는 차선이탈경보 애플리케이션으로 개발하고 처리 속도를 최적화하였다. 효율적인 영상처리를 위해서 OpenCV를 사용하였고, 차선인식을 위해서는 차선의 기하학적 특징을 고려한 Hough Transform 기반의 휴리스틱 알고리즘이 고안되었다. 차선이탈경보 애플리케이션은 매킨토시 컴퓨터에서 Xcode 3.2.4 개발툴을 사용하여 개발되었고, 스마트폰에 다운로드하여 실제 도로에서 실험하였다. 실험결과 1.52fps의 처리 속도를 보였고, 최적화 작업을 통해 처리 속도를 3.84fps까지 향상시켰다. 향후 차선인식 알고리즘 보완, 추가 최적화 작업 및 고성능 스마트폰 플랫폼 채택 등을 통해 스마트폰용 차선이탈경보 애플리케이션을 상용화할 계획이다.

• 한국재난정보학회 논문집
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• 제19권2호
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• pp.241-253
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• 2023

연구목적:본 연구의 목적은 위험 지식/지각 증진을 위하여 개발된 어플리케이션(KNOWRISK)의 구성과 기능을 소개하고 본 어플리케이션의 사용성 평가 결과를 바탕으로 문제 및 요구사항을 파악 및 결정하는 것이다. 연구방법: 어플리케이션 사용자와 관련 전문가 43명을 대상으로 MARS를 활용하여 평가를 진행하였다. 연구결과: 전체 평균 4.074점으로 만족스러운 평가 점수를 받았고 전문가와 사용자 간에 평가 점수에 유의미한 차이가 없었다. 높은 점수는 사용하기 쉬움이 4.47이었고, 비용 지불 사용이 2.88점으로 가장 낮았다. 결론: 본 연구 결과는 모바일 어플리케이션을 이용한 위험지식 증가와 안전행동 증진 노력이 근로자의 산업재해를 예방하고 안전관리에 효과적이고 효율적인 전략으로 사용될 수 있음을 시사한다.

• Safety and Health at Work
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• 제8권1호
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• pp.59-66
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• 2017

Background: Despite considerable efforts made in recent years, the industrial accident rate and the fatality rate in the Republic of Korea are much higher than those in most developed countries in Europe and North America. Industrial safety policies and safety regulations are also known to be ineffective and inefficient in some cases. Methods: This study focuses on the quantitative evaluation of the effectiveness of direct safety regulations such as safety certification, self-declaration of conformity, and safety inspection of industrial machines in the Republic of Korea. Implications on safety policies to restructure the industrial safety system associated with industrial machines are also explored. Results: Analysis of causes in industrial accidents associated with industrial machines confirms that technical causes need to be resolved to reduce both the frequency and the severity of such industrial accidents. Statistical analysis also confirms that the indirect effects of safety device regulation on users are limited for a variety of reasons. Safety device regulation needs to be shifted to complement safety certification and self-declaration of conformity for more balanced direct regulations on manufacturers and users. An example of cost-benefit analysis on conveyor justifies such a transition. Conclusion: Industrial safety policies and regulations associated with industrial machines must be directed towards eliminating the sources of danger at the stage of danger creation, thereby securing the safe industrial machines. Safety inspection further secures the safety of workers at the stage of danger use. The overall balance between such safety regulations is achieved by proper distribution of industrial machines subject to such regulations and the intensity of each regulation. Rearrangement of industrial machines subject to safety certification and self-declaration of conformity to include more movable industrial machines and other industrial machines with a high level of danger is also suggested.

• 산업경영시스템학회지
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• 제33권4호
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• pp.187-192
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• 2010

Korean railway has run about 110 years since 1989 and played a great role of industrialization in Korea. It is known that rail transport systems have many advantages of being more safe, energy-efficient, and environment-friendly, as compared to other transportation systems. However, railway incidents are often attributed to the failure of safety management and critical to the efficiency of railroad industry. This study reviewed economic, financial, and general statistical information on Korea Railroad. Based on the statistical data, the effect of accidents on railroad management was analyzed. Correlation analysis revealed that railway accident had a negative effect on the gross profit of Korea Railroad. In order to reduce potential risks and incident rate, some recommendations are proposed. Actual or potential applications of this research include safety guidelines for improving efficiency of railroad industry.

• 산업공학
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• 제25권4호
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• pp.422-430
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• 2012

In this article, we introduced the estimation method by 'Safety Integrity Level'(SIL) for the criterion of safety assurance and performed a case study on a flame scanner. SIL requires probabilistic evaluation of each set of equipment used to reduce risk in a safety related system. FMEDA(Failure Modes, Effects and Diagnostic Analysis) method is widely used to evaluate the safety levels and provides information on the failure rates and failure mode distributions necessary to calculate a diagnostic coverage factor for a part or a component. Basically, two parameters resulting from FMEDA are used for SIL classification of the device : SFF(Safe Failure Fraction) and PFD(Probability of Failure on Demand). In this case study, it is concluded that the flame scanner is designed to fulfill the condition of SIL 3 in the aspect of SFF and PFD.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.166-168
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• 2002

This paper presents a new numerical algorithm suitable for defining recloser reclaims time and blocking automatic reclosing during permanent faults on overhead lines. It is based on terminal voltage input data processing. The decision if it is safe or not to reclose is determined from the voltage signal of faulted and tripped line phase using Total Harmonic Distortion factor calculated by Discrete Fourier Transform. The algorithm was successfully tested using signals recorded on the real power system. The tests demonstrate the ability of presented algorithm to determine the secondary arc extinction time and to block unsuccessful automatic reclosing of HV lines with permanent fault.

• 한국안전학회지
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• 제20권1호
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• pp.137-142
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• 2005

This study aims to survey the fatal industrial accidents attributed to crane, and to present their preventive measures based on the results of the survey. The survey was on the basis of 60 fatal accidents caused by crane from January 1998 to July 2003. The results showed that 1) of varying types of crane, fatal accidents were most frequently caused by mobile no: 2) more crane accidents occurred on weekend of Friday and Saturday by a day of the week; 3) experienced crane operators with long length of work or the age of over 40 were more frequently subjected to fatal accidents compared to novice operators; and 4) crane accidents were more attributable to unsafe acts such as poor working method, non-observance for safe working rules, etc. than hardware aspects of crane itself. It is recommended that for reducing crane accidents, more practical education and training for crane operation be reinforced.

• 화약ㆍ발파
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• 제9권4호
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• pp.13-21
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• 1991

This study is concerned with the disasters that occure in the field of industrial explosives and analyzed by two side the disaster of the manufacturing factory and that of the field, and is studied about the safety and the countermeasure. The industrial explosives accidents occure just accidentaly and unforeseeable, and reappearance experiments are more difficult. The 3E of J.H. Harvey was applied in this study to establish the counter measure of preventation of accidents, overcoming these restricted factores. As a method of technical safety countermeasures. The blasting vibration formula which had been conformed from the Seoul Subway Construction work during 1980-1984 year, was uilized, and, using the formula $V=Kw^{0.5}D^{-1.5}$ for the gneiss which is widely distributed in Pusan area, an index of the minimum and maximum amount of gun powder, to be used according to safety distance was made, and it helped the gun powder managing technician's practical business. During the fore work discharging, the safety distances of felling were theoretically established based on the writer ${\diagdown}s$ experiences of more than 10 years on this field.