• Proceedings of the Safety Management and Science Conference
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• 2004.05a
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• pp.277-281
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• 2004

The establishment and application of risk management system is one of the current issues in world-wide leading companies. Poor risk management might bring large-scale accident in construction industry by its features(large scale, diversity). Standardization system and standard for risk should be managed timely. In this paper, we do comparative analysis of standardization systems and standards concerned on risk, so thus present basic data for safety reinforcement and risk zero in the construction life cycle process.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.1
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• pp.26-32
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• 2017

Enlargement and speed-up of a ship and diversification of ship's type have served to greatly increase the importance of marine transport means. It's reported that accident occurrence frequency of collision is high next to engine damage among the ship accident types, and that the accident ratio according to human factors is also high. In addition, ship accidents come to occur caused by complex cause factors rather than a sole cause factor, it is necessary to investigate the cause factors through the written verdict. This study proposed the cause factors of collision ship accident on the basis of human factors in collision ship accident among the written verdicts provided by the Korean Maritime Safety Tribunal, and inquired into the cause factor and effect through the correlation analysis of accident occurrence factors. Also, this study predicted the collision accident through analyzed the major cause factor of the occurrence at the zero minute when collision on the basis of the time taken from the time point of detecting collision of ships to the time point of collision occurrence. This study used commercial software-Statistical Package for Social Sciences (SPSS Ver21.0) to do correlation analysis. For time analysis, this study analyzed the cause factor and time by analyzing the time taken from the time point of detected ships to the time point of collision occurrence on the basis of the written verdicts. The study analysis showed that there were many cases of collision ship accidents occurrence caused by more than two sorts of cause factors, and that the case (zero minute) where there is no time to spare for collision avoidance accounted for 36.1 %, and negligence in guard or surveillance of the other ship, and sailing while drowsy, or drinking was a contributor to an accident. Poor watch keeping is very strong relationship with pool ready for sail.

• International Journal of Highway Engineering
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• v.14 no.2
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• pp.131-143
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• 2012

The past researches on roadway segment safety estimation focused on intersections, which are the primary traffic accident regions. The past researches on roadway segments, However, analyzed the effects of certain factors on the traffic accident occurrence rate by organizing the individual geometric structures of the roads, and there is still a dearth of researches on the development of a traffic accident estimation model for rural roadway segments. Therefore, this research focused on rural two-lane and multilane roadway segments and developed traffic accident estimation models through the application of statistical techniques. This is required to explain such high frequency of zero counts in the traffic accident data. In this research, it was found that the Hurdle model is more suitable than the Poisson or negative binomial-regression model for explaining the excess zeros case. In addition, main variables were chosen to estimate their effects on traffic accident occurrence at rural roadway segments, and the safety at such rural roadway segments was estimated. In this research, it was assumed that there are different factors that affect the safety at two-way lane and multilane roadway segments, and a traffic accident estimation model was developed by dividing the two-way lane and multilane roadway segments.

• Journal of the Korean Solar Energy Society
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• v.38 no.4
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• pp.55-66
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• 2018

nZEH (net-Zero Energy House) is defined as a self-sufficient energy building where the sum of energy output generated from new & renewable energy system and annual energy consumption is zero. The electricity generated by new & renewable energy system with the form of distributed generation is preferentially supplied to electrical demand, and surplus electricity is transmitted back to grid. Due to the recent expansion of houses with photovoltaic system and the nZEH mandatory by 2025, the rapid increase of distributed generation is expected. Which means, we must prepare for an electricity-power accident and stable electricity supply. Also electricity charges have to be reduce and the grid-connected should be operated efficiently. The introduction of ESS is suggested as a solution, so the analysis of the load matching and grid interaction is required to optimize ESS design. This study analyzed the load matching and grid interaction by expected consumption behavior using actual data measured in one-minute intervals. The experiment was conducted in three nZEH with photovoltaic system, called all-electric houses. LCF (Load Cover Factor), SCF (Supply Cover Factor) and $f_{grid}$ (Grid Interaction Index) were evaluated as an analysis indicator. As a result, LCF, SCF and $f_{grid}$ of A house were 0.25, 0.23 and 0.27 respectively; That of B house were 0.23, 0.23, 0.19, and that of C were 0.20, 0.19, 0.27 respectively.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.2
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• pp.250-257
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• 2012

Currently, large vessels and structures are manufactured into set of blocks, then assembled on-site. Large scale ships that weigh thousands of tons are built in a short period by making set of large blocks and assembled on a dock or a land. When a transporter encounters a slope during the process of transporting blocks, the heavy goods loaded on the transporter can be tilted. Further, if the vehicle moves down the slope in this state then it can cause an accident of overturn of loaded goods. The research has been taken into account to calculate the center of gravity of the transporter carrying heavy objects on a leveled surface or the three dimensions. In addition, ZMP (Zero Moment Point) is used to calculate the allowable slope degree that objects are predicted to overturn. Through the simulation, the objects' stability is tested when it is climbing the slope.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.6
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• pp.995-1000
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• 2017

In this paper, we present an electrical arc detection algorithm using the mash-up analysis technique which is the core technology for the autonomous electrical safety management system(AESMS) of the multi-unit dwellings. The mash-up analysis technique analyzes the voltage, load current, zero phase current data simultaneously to judge arc faults. In order to develop the arc fault detection algorithm, the characteristics of series arc and parallel arc were analyzed. Also, we propose the mash-up analysis technique that analyzes waveforms of voltage, load current, and zero phase current at the same time. The arc fault detection algorithm was developed using the mash-up analysis technique. The developed algorithm can prevent electrical disasters in an effective way through accident prediction, and it will be used as a basic technology to introduce an autonomous electrical safety management system.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.2
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• pp.253-259
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• 2018

In February 2014, the rudder upper stock and the nut of a passenger ship were released and an accident occurred. That accident occurred because the steering gear of passenger ships that was intended to move many passengers. The accidents due to steering gear was zero according to 2010-2016 statistics. There is no rules prevent loosening of the upper rudder nut in "Ship Safety Act" and "Structural standard of steel ship". Since the accident, the Korea register has been revised to the joining method in Part 5 Chapter 7 of the rules in the classification of steel ships. In the field survey of 12 passenger ships operating on Mokpo and surrounding islands, the welding method was applied in the cases as the fastening method. The fastening type was equipped with two C-type structures. It was structured to be difficult to access. The NAS 3350 test was conducted to investigate ways to prevent homologous accident considering the characteristic of passenger ships that need to lift or unload rides once a year.

• Proceedings of the KIEE Conference
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• 2008.09a
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• pp.301-304
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• 2008

In this paper, we study from of flowing leakage current in electrical installation. Leakage current is expressed by a resistivity leakage current($I_{gr}$), a capacitive leakage current($I_{gc}$), an inductivity leakage current($I_{gl}$). General Zero Phase Current Transformer (ZCT) detect a leakage current($I_{g}$) that are conjoined resistivity leakage current and capacitive leakage current. In case $I_{gr}$ is big than $I_{gc}$, there is no singular problem in leakage current detection of system. But, in case $I_{gc}$ is big than $I_{gr}$, earth leakage breaker can not prevent accident effectively. Can lower electric leakage perception current to 5 mA if apply resistivity leakage current detecting circuit. We can achieve prevention of electricity disaster spontaneously.

• Journal of the Korean Society of Safety
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• v.22 no.5
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• pp.65-70
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• 2007

This paper is estimation of structure damage caused by VCE(Vapor Cloud Explosion) in enclosure. As we estimate the influence of damage which occur at gas facility in factory. We can utilize the elementary data of safety distance. In this study, the influence of over-pressure caused by VCE in enclosure was calculated by using the Hopkinson's scaling law and the accident damage was estimated by applying the influence on the adjacent structure into the probit model. As a result of the damage estimation conducted by using the probit model, both the damage possibility of explosion overpressure to structures of 20 meters away and to glass bursting of 80 meters away was nearly zero in open space explosion.

• International Journal of Safety
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• v.1 no.1
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• pp.1-6
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• 2002

It is important to control the high accurate position and force to prevent unexpected accidents by a robot manipulator. Direct-drive robots are suitable to the position and force control with high accuracy, but it is difficult to design a controller because of the system's nonlinearity and link-interactions. This paper is concerned with the study of the stabilization force control of direct-drive robots. The proposed algorithm is consists of the feedback controllers and the neural networks. After the completion of learning, the outputs of feedback controllers are nearly equal to zero, and the neural networks play an important role in the control system. Therefore, the optimum adjustment of control parameters is unnecessary. In other words, the proposed algorithm does not need any knowledge of the controlled system in advance. The effectiveness of the proposed algorithm is demonstrated by the experiment on the force control of a parallelogram link-type robot.