• Journal of the Earthquake Engineering Society of Korea
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• v.5 no.6
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• pp.55-64
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• 2001

Industrial machines are sometimes exposed to the danger of earthquake. In the design of a mechanical system, this factor should be accounted for from the viewpoint of reliability to analyze a complex nonlinear structure system under random excitation is proposed. First, the actual random excitation, such as earthquake, is approximated to the corresponding Gaussian process for the statistical analysis. The modal equations of overall system are expanded sequentially. Then, the perturbed equations are synthesized into the overall system and solved in probabilistic way. Several statistical properties of a random process that are of interest in random vibration are evaluated in each substructure. Comparing with the results of the numerical simulation proved the efficiency of the proposed method.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.3
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• pp.38-45
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• 2018

The purpose of this study is to deduct the structural damage / work process risks factors which can be occurred during the decommissioning in the NPP containment concrete structure. To achieve these purpose, risk profile specified in the construction industry is analyzed, and the work process of NPP decommissioning and the construction project were matched based on the similarity of each works. Accordingly, human and physical risk factors are classified. Finally, the risk associated with the building structure and work process was classified as per their process activities, and risk typology explaining the disaster which put the structure, equipments, machine and workers in serious danger was developed.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.2
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• pp.121-131
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• 2008

Two dimensional road design is connoting danger factor because different point between design standard and driver's reaction. Consequently two dimensional road design is difficult to recognize problem that happen beforehand when before construction. Therefore three dimensional road design that can grasp problem after completion is required. In this study, three dimensional road was designed to evaluate road that is designed. Road designed by Inroad that is road design program. DTM is created using digital map and elevation data. Three dimensional road was designed by integrated DTM of road and topography. Road design evaluation was performed in three dimension. Driving simulation and sight distance assessment were carried out to estimate stability of alignment. Shadow simulation was executed on icy road section for bad section of icy road surface. As a result of evaluation, this study could confirm shape of road after completion. And sight distance could be calculated and visually confirmed. Also, icy road sections were extracted through shadow simulation.

• Journal of the Korea Safety Management & Science
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• v.15 no.1
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• pp.31-40
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• 2013

For the matter of elevator, one of the multi-use facilities for unspecified public, the JIS has re-established and reformed to apply to the environment in South Korea for the past 20 years. In the aspect of safety assurance, it was inevitable to suggest improved measures. The government, Ministry of Public Administration and Security has secured the safety by enhancing the safety management functions in the elevator inspection standards and expanding its safety device measures. Further, the international inspection standard has been introduced, which is about unifying inspection standard system into the international standard code. In March 14th 2012, the international standard (EN) has been amended and fully announced. Escalator and passenger conveyor among lift devices have several common danger factor that cause safety accident. First, the accident caused by decreased braking power of brake. Second, the accident caused by the rate difference between handrail and tread-board. Third, the accident caused by defects of contraflow preventing device or carelessness inspection. Fourth, the accident caused by wet tread-board or wet floor of platform which makes passenger slip and fall. As the improvements to prevent and reduce these negligent accidents, the inspection list to check and methods should be subdivided and applied for each accident likelihood cause for safety management enhancement and safety assurance of existing escalator and passenger conveyors. The escalators and passenger conveyors without safety devices in existence should be obliged to modify the part of the system or install additional safety device. With making these measures obligations, it requires to improve the system to be suitable for the international inspection standard and to have measures to prevent safety accidents. It also needs to arrange improvements for skid accident of tread-board by the external environment factors such as snow and rain.

• Journal of Families and Better Life
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• v.21 no.2
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• pp.19-30
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• 2003

In this study, housewives' attitudes toward genetically modified foods (GM foods) and their willingness to purchase GM foods were examined. The findings of this study could provide useful information for consumer education and consumer policy development regarding GM foods. The specific purposes of this study were: (1) to examine consumers' attitudes toward GM foods, (2) to analyze the effect of the perception of GM foods and demographic variables on consumers' attitudes toward GM foods, and (3) to analyze the effect of the perception of GM foods and demographic variables on consumers' willingness to purchase GM foods. The questionnaire used in the survey was constructed by the author, based on existing literature. The survey was conducted with 1,100 housewives, and 723 of the completed survey forms were used in the final analysis. Frequencies, percentages, means, standard deviation, t-tests, ANOVA, Duncan-test, Pearson's Correlation, factor analysis, and discriminant analysis were employed for data analysis methods. Major findings are: (1) Consumers' attitudes toward GM foods consist of three factors, that are, attitude regarding potential danger, attitude regarding the use of GM technique on plants, and attitude regarding the use of GM technique on animals. (2) Consumers with a higher level of education tend to perceive GM food as more dangerous, whereas consumers with a lower level of education tend to accept more the use of GM technique on plants. (3) Consumers who tend not to consider GM foods as dangerous, and those who acknowledged benefits in using GM technique on plants are more willing to buy GM foods.

• Journal of Digital Convergence
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• v.18 no.10
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• pp.239-252
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• 2020

By using text mining, we explore the factors responsible for an increase in SUV preference. We collected 32,679 posts related to SUVs from "Bobaedream," the largest online automobile community in South Korea, and applied the LDA topic model. While previous studies have explained the SUV boom as an individual's risk aversion strategy from crime, the result shows that the topic of 'Safety' appears to be an important factor in the SUV discourse in the context of a car accident and high-speed driving situation. To conclude, the consumption of SUVs in Korean society serves as a mean to prevent anxiety and danger to individuals when driving. We insist that decreasing social trust, caused by an increase in inequality, underlies the perception of risk on the road.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.3
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• pp.379-385
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• 2012

This paper developes the navigation visual aid supporting a watch officer's situation awareness and analyzes its performance test result. Developing the equipment made from composite video sensor which transfer video signal, ranger laser measurement model which search out distance, Pan/ Tilt, center control device. The developed equipment with Pan/Tilt was made from high performance video sensor and ranger laser measurement. To make a real ship test, we carried on setting the developed equipment on ship, observed a danger factor and analyzed a image, and from that we can evaluate marine environment awareness. Through this result, the developed equipment can show effective ability of the awareness of the clearer check and resolution situation when compare with the binocular.

• Journal of the Korean Institute of Navigation
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• v.24 no.1
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• pp.13-22
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• 2000

The collisions at sea among marine casualties are not reduced as the tonnage and speed of ship's increase as well as the traffic quantity increase at sea, in spite of the improvement of nautical equipment, enforcement of crew's education and training as well as improvement of quality standard according to the implementation of ISM code. The measures to prevent the collisions at sea are simple, and are composed of six stage.: The first stage is that the officer on duty detect the target from his eye or radar information. The second stage is determining the type and kind of target-ship. The third stage is target tracking; calculation of target speed, course, CPA and TCPA from radar information or visual check. The fourth stage is determination of vessel in danger after calculation of third stage. The fifth stage is the judgement of situation if own ship is stand-on or give way vessel according to the 1972 COLREG. The last stage is to carry out proper action according to 1972 COLREG, under the circumstances. But by the case, the situations are so different under the different external conditions; for example, natural/navigational conditions, crew's human factors, ship's particular, rule or regulation, management system on board, the condition of watch keeping. Therefore the reasons and casualties are so complicated. This study aims to investigate the collision casualty at sea which needs to clarity all these causal factors of afore-mentioned, and to analyze the causes of problems so as to utilize them to establish the measures of preventing marine accidents. This study, described the concepts of causal factors into three groups; environmental factor, and company/on board management system and navigator's act. Also described how to investigate and analyzes the casual factors. Even though it was described in this paper how to detect the causal factors and reasons of collisions, and how to analyze the inter-relation of each causal factors, it is necessary to do further study how to analyze between the liability of concerned parties and the casual factors involved.

• Journal of Navigation and Port Research
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• v.33 no.1
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• pp.1-7
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• 2009

Navigation speed control is an important factor to improve the traffic safety, it is only researched about maximum speed control until now. Recently, there are lots of the low speed vessels including towing boats, carry heavy shipbuilding blocks in the Korean waters, so the danger degree of navigating vessels was increasing more and more. This paper analysed the effectiveness of minimum speed control with the operation burden's decrease, and it proposed the proper the minimum navigation speed of each traffic volume. Main results of this research are as follows. (1) in the case of 5 ships/hour, minimum speed control is effective if the lowest speed is fixed more than 5kts. (2) in the case of more than 10 ships/hour, speed control is some effective if the lowest speed is established 7kts. (3) But, when there are many ships in the waters, minimum speed control is not effective because distances between ships become near and ships navigate for a long time by a lot of ship having a few difference of relative speed.

• 한국가시화정보학회:학술대회논문집
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• 2006.12a
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• pp.17-20
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• 2006

Passenger safety is fundamental factor in automobile. Among much equipment for passenger safety, the air bag system is the most fundamental and effective device. Beside of the front air bag system which installed on most of all automobiles, a curtain-type air bag is increasingly adapted in deluxe cars fur protecting passengers from the danger of side clash. Curtain type airbag system consists of inflator housing, fill hose, curtain airbag. Inflator housing is a main part of the curtain-type air bag system for supplying high-pressure gases to deploy the air bag-curtain. Fill hose is a passageway to carry the gases from inflator housing to each part of curtain airbag. Therefore, it is very important to design the vent holes of fill hose for good performance of airbag deployment. But, the flow information from vent holes of fill hose is very limited. In this study, we measured instantaneous velocity fields of a high-speed flow ejecting from the vent holes of fill hose using a dynamic PIV system. From the velocity Held data measured at a high frame-rate, we evaluated the variation of the mass flow rate with time. From the instantaneous velocity fields of flow ejecting from the vent holes in the initial stage, we can see a flow pattern of wavy motion and fluctuation. The flow ejecting from the vent holes was found to have very high velocity fluctuations and the maximum velocity was about 480m/s at 4-vent hole region. From the mass flow rate with time, the accumulated flow of 4-vent hole has occupied about 70% of total flow rate.