• Journal of the Korean Society of Safety
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• v.11 no.2
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• pp.67-78
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• 1996

Gas sensing element, $\gamma-Fe_2O_3$was synthesized by dehydration, reduction, and oxidation of $$${\gamma}$-FeOOH, which was synthesized with $FeSO_4\;{\cdot}\;7H_2O$ and NaOH. They were produced as a bulk-type, a thick film-type. Then, their responses and mechanisms of response to the gas of liquefied-petroleum were studied. The qualities of gas sensing elements are decided by the structure and the relative surface area. In the process of $\alpha-FeOOH $synthesis, the effects of reaction conditions as the equivalent ratio, on the structure and the relative surface area of gas sensing element were observed. The changes of the structure were measured with XRD, SEM, TG-DTA and BET. The resistance changes of the synthesized gas sensor in the air were measured. The response ratio were also measured for the changes of working temperature and gas concentration. As a result of analysis with XRD, it was confirmed that the the best conditions for the synthesis of $\alpha -FeOOH$ were equivalent ratio 0.65. The thick film-type element of $\gamma-Fe_2O_3$responded more quickly than the bulk-type did. The structure and the relative surface area of the $\alpha-FeOOH $were confirmed as the important factors deciding gas response charcteristics.

• Journal of the Korea Safety Management & Science
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• v.19 no.4
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• pp.169-182
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• 2017

Predicting a box office gross in the film industry is an important goal. Many works have analyzed the elements of a film making. Previous studies have suggested several methods for predicting box office such as a model for distinguishing people's reactions by using a sentiment analysis, a study on the period of influence of word-of-mouth effect through SNS. These works discover that a word of mouth (WOM) effect through SNS influences customers' choice of movies. Therefore, this study analyzes correlations between a box office gross and a ratio of people reaction to a certain movie by extracting their feedback on the film from before and after of the film opening. In this work, people's reactions to the movie are categorized into positive, neutral, and negative opinions by employing sentiment analysis. In order to proceed the research analyses in this work, North American tweets are collected between March 2011 and August 2012. There is no correlation for each analysis that has been conducted in this work, hereby rate of tweets before and after opening of movies does not have relationship between a box office gross.

• Proceedings of the Korean Society for Quality Management Conference
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• 2010.04a
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• pp.254-261
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• 2010

The increase in hazard level is attributed to the industrial hazard environment; complete national environmental hazards to human health include climate change. The damage level in Korea from 1993 to 2009 has exceeded the Increase In adverse environmental conditions. Priority areas of concern will include those risks that are most likely to occur and are expensive when they do take place such as accident or injury at a community pool. Therefore, in this paper, we suggest the System Engineering method for application to the railway RAMS. Recently, the requirement of high-integrity level of infrastructure has been deemed important. The systems level approach is defined through the assessment of the RAMS interactions between elements of complex system applications.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.949-952
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• 2006

An understanding of rheological property on cement paste is one of the important factor to design concrete such as High-fluidity Concrete (HFC) for a specific application. The HFC is a specially proportioned hydraulic cement concrete that enables the fresh concrete to flow easily into the forms and around the reinforcement and prestressing steel without vibration and segregation. Use of this type of concrete for the concrete building construction, manufacture of precast, prestressed bridge elements provides the benefits of increased rate of production and safety, reduced labor needs, and lower noise levels. This paper presents the performance of rheological properties of cement paste incorporating domestic high-water-reduced-admixture (HWRA) for an Ultra-high-fluidity concrete (UHFC). Investigation was carried out on cement pastes with combinations of various dosages of HWRA and water/cement ratios.

• Food Science of Animal Resources
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• v.44 no.1
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• pp.19-38
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• 2024

Meat contains high-value protein compounds that might degrade as a result of oxidation and microbial contamination. Additionally, various pathogenic and spoilage microorganisms can grow in meat. Moreover, contamination with pathogenic microorganisms above the infectious dose has caused foodborne illness outbreaks. To decrease the microbial population, traditional meat preservation methods such as thermal treatment and chemical disinfectants are used, but it may have limitations for the maintenance of meat quality or the consumers acceptance. Thus, non-thermal technologies (e.g., high-pressure processing, pulsed electric field, non-thermal plasma, pulsed light, supercritical carbon dioxide technology, ozone, irradiation, ultraviolet light, and ultrasound) have emerged to improve the shelf life and meat safety. Non-thermal technologies are becoming increasingly important because of their advantages in maintaining low temperature, meat nutrition, and short processing time. Especially, pulsed light and pulsed electric field treatment induce few sensory and physiological changes in high fat and protein meat products, making them suitable for the application. Many research results showed that these non-thermal technologies may keep meat fresh and maintain heat-sensitive elements in meat products.

• Korean Institute of Interior Design Journal
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• v.24 no.3
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• pp.3-14
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• 2015

The most important issue of modern cities is a crime. Crime prevention through environmental planning is needed in the urban mixed-use commercial facilities which have an important role of modern urban life, and have a positive elements for local society. The purpose of this study is to propose a direction of crime prevention through environmental planning for the urban mixed-use commercial facilities. In order to accomplish this purpose, a questionnaire survey is performed on users of urban mixed-use commercial facilities to evaluate the importance and satisfaction. The conclusions are as follows; 1) Crime prevention through environmental planning is needed in the public space which forms boundary between urban mixed-use commercial facilities and other urban facilities. 2) Safety support planning is necessary for women and children for crime prevention of urban mixed-use commercial facilities. 3) Crime prevention planning is needed in urban mixed-use commercial facilities of the various isolation space. 4) Crime prevention through environmental planning is needed for facilities of after business hours. 5) Various security alarm system considering the characteristics of the space is needed for crime prevention. 6) Community program is necessary in order to increase the utilization of external public space. 7) A sign is necessary to prevent a criminal act in urban mixed-use commercial facilities. 8) The connection of commercial facilities and activity inducing factors is needed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.229-231
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• 2012

The supply chain in plant construction project can be defined as a network combined between elements which is engineering, procurement, construction, start-up. For successfully leading construction project, close relation and mutual cooperation should be preceded and Supply Chain Management(SCM) system is needed to improve the relation. In particular, because safety is a top priority for the companies work in the construction of Nuclear Power Plant(NPP), it is necessary to control all parties realated with NPP construction systematically. In this situation, it is important to purchase high-quality equipment in timely manner by developing Integrated cooperative systems. Therefore, this study aimed to propose developing solutions of SCM such as JIT and Envelop Design system, which can reduces difficulties of decision making between the parties involved in the project and will increase the efficiency of the engineering process in NPP.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.10a
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• pp.695-700
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• 1997

To enhance the safety of nuclear power plants, implementation of accident management has been suggested as one of most important programs. Specially, accident management strategies are suggested as one of key elements considered in development of the accident management program. In this study, generally applicable accident management strategies to domestic nuclear power plants are identified through reviewing several accident management programs for the other countries and considering domestic conditions. Identified strategies are as follows; 1) Injection into the Reactor Coolant System, 2) Depressurize the Reactor Coolant System, 3) Depressurize the Steam Generator, 4) Injection into the Steam Generator, 5) Injection into the Containment, 6) Spray into the Containment, 7) Control Hydrogen in the Containment. In addition, the systems and instrumentation necessary for the implementation of .each strategy are also investigated.

• 한국기계연구소 소보
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• s.13
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• pp.123-141
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• 1984

The safety aspects of ship handing have become increasingly important recently, due to the changes in sea transportation. These are characterizes by larger units, increased traffic density on sea lane, sea transport of dangerous cargo, etc. In addition, as a economic aspect of ship handing, it has obtained an increased attention in connection with port development and consideration of allowable ship size for existing ports. One method for evaluation of maneuvering problems is simulation on a computer by means of a mathematical model of the ship maneuvering motion. The present report describes the elements of a mathematical model for ship maneuvering and gives some results of maneuvering predictions through the simulation.

• Computers and Concrete
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• v.23 no.6
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• pp.399-408
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• 2019

Structural health monitoring is important for the safety of lives and asset management. In this study, numerical models were developed for the piezoresistive behavior of smart concrete based on finite element (FE) method. Finite element models were calibrated with experimental data collected from compression test. The compression test was performed on smart concrete cube specimens with 75 mm dimensions. Smart concrete was made of cement CEM II 42.5 R, silica fume, fine and coarse crushed limestone aggregates, brass fibers and plasticizer. During the compression test, electrical resistance change and compressive strain measurements were conducted simultaneously. Smart concrete had a strong linear relationship between strain and electrical resistance change due to its piezoresistive function. The piezoresistivity of the smart concrete was modeled by FE method. Twenty-noded solid brick elements were used to model the smart concrete specimens in the finite element platform of Ansys. The numerical results were determined for strain induced resistivity change. The electrical resistivity of simulated smart concrete decreased with applied strain, as found in experimental investigation. The numerical findings are in good agreement with the experimental results.