• Journal of Korea Water Resources Association
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• v.42 no.7
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• pp.547-558
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• 2009

General reliability assessment of levees embankment is performed with safety factors for rainfall characteristics and hydrologic and hydraulic parameters, based on the results of deterministic analysis. The safety factors are widely employed in the field of engineering handling model parameters and the diversity of material properties, but cannot explain every natural phenomenon. Uncertainty of flood analysis and related parameters by introducing stochastic method rather than deterministic scheme will be required to deal with extreme weather and unprecedented flood due to recent climate change. As a consequence, stochastic-method-based measures considering parameter uncertainty and related factors are being established. In this study, a variety of dimensionless cumulative rainfall curve for typhoon and monsoon season of July to September with generation method of stochastic temporal variation is generated by introducing Monte Carlo method and applied to the risk assessment of levee embankment using reliability index. The result of this study reflecting temporal and regional characteristics of a rainfall can be used for the establishment of flood defence measures, hydraulic structure design and analysis on a watershed.

• Journal of Food Hygiene and Safety
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• v.12 no.3
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• pp.240-253
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• 1997

The main problems contributing to food poisoning outbreaks in institutional settings and a home were reviewed and analyzed through the epidemiological investigations of food poisoning. The major documented factors included improper holding temperatures, inadequate cooking, poor personal hygiene, cross-contamination and contaminated equipment, food from unsafe sources, failure to follow food hygiene policies, and lack of education, training, monitoring and superivision. Usually more than one factor contributed to the development of an outbreak. (1) Use of improper holding temperatures was the single most important factor contributing to food poisoning. They included improper cooling, allowing a laps of time (12 hours or more) between preparing food and eating it, improper hot holding, and inadequate or improper thawing. Food thermometers were not used in most of the instances. (2) In inadequate cooking, the core temperature of food during and after cooking had not been measured, and routine monitoring was limited to recording the temperature of plated meals. Compared with conventional methods of cooking, microwave ovens did not protect against food poisoning as effectively. Centralized food preparation potentially increased the risk of food poisoning outbreaks. (3) Poor personal hygiene both at the individual level (improper handwashing and lack of proper hygienic practices) and at the institutional level (poor general sanitization) increased the risk of transmission. Person to person transmission of enteric pathogens through direct contact and via fomites has been noted in several instances. (4) Obtaining food from unsafe sources was a risk factor in outbreaks of food poisoning. Food risks were high when food was grown or harvested from contaminated areas. Possibilities included contamination in the field, in transport, at the retail site, or at the time it was prepared for serving. (5) Cross-contamination and inadequate cleaning/handling of equipment became potential vehicles of food poisoning. Failure to separate cooked food from raw food was also a risk factor. (6) Failure to follow food hygiene policies also provided opportunities for outbreaks of food poisoning. It included improper hygienic practices during food preparation, neglect of personnel policies (involvement of symptomatic workers in food preparation), poor results on routine inspections, and disregarding the results and recommendations of an inspection. (7) Lack of formal and in-service education, training, monitoring, and supervision of food handlers or supervisors were critical and perhaps neglected elements in occurrences of food poisoning.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.333-340
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• 2010

This study was conducted to evaluate the microbial contamination levels in the processing company of Nuroong-ji. Microbial contamination levels were examined for sanitary indication bacteria such as aerobic plate count, coliforms and fungi, and pathogenic bacteria such as Escherchia coli O157:H7, Salmonella spp., Staphylococcus aureus, and Listeria monocytogenes. Contamination levels were detected differently according to handling materials and purposing work-space. The equipments and raw materials were not seriously contaminated but there were necessary to attend the cross-contamination. A high contamination level was detected at the process where the interference of the employees was relatively higher than the other process. Standardization of the roasting process (l20~$170^{\circ}C$, about 10 min) could be necessary to control the microbial organism effectively on Nuroong-ji manufacturing process. At small/medium size foodstuff manufacturers, it is the most important to improve the recognition level of individual hygiene but also expand a hygiene facility.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.2
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• pp.193-201
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• 2014

This study provided safe sailing speed and appropriate passing time to areas of known strong current water to prevent marine accident of the ships. To the interpretation of these data which target Myeongnyang waterway, AIS data of the ship was collected from $12^{th}$ July to $15^{th}$ July 2010 and site environment was investigated on $4^{th}$ September 2010. On the basis of the collected data, the 'Minimum Navigation Speed' and 'Optimum Navigation Speed' were calculated. It has also considered the 'Spare control force' or allowance and the 'Respond Rudder Angle' for each tidal current speed. Additionally, it suggested the safe passing time to strong current area by analyzing tidal level and tidal current speed. The conclusion of the research are as follows : (1) If the flow rate is greater than 4.4 kn, it is difficult for the model ship to control herself by her own steering power and to cope with tidal current pressure force and yaw moment caused by the tidal current.. (2) The minimum navigation speed should be over 2.3 times the tidal current and the optimum navigation speed should be over 4.0 times the tidal current. (3) When spring tide, the optimum passing time at Myeongnyang waterway is between 30 minutes to 1 hour before the time of high/low water, and at 5 hours after high/low water, passing of ships should be avoided because it is time when the flow rate is over 4 kn.

• Journal of the Korean Society of Safety
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• v.11 no.2
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• pp.150-159
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• 1996

In this paper, an A-team(Asynchronous Team ) based approach for Reactive power and volage control considering static security assessment in a power system with infrastructural deficiencies is proposed. Reactive power and voltage control problem is the one of optimally establishing voltage level given several constraints such as reactive generation, voltage magnitude, line flow, and other switchable reactive power sources. It can be formulated as a mixed-integer linear programming(MILP) problem without deteriorating of solution accuracy to a certain extent. The security assessment is to estimate the relative robustness of the system in Its present state through the evaluation of data provided by security monitoring. Deterministic approach based on AC load flow calculations is adopted to assess the system security, especially voltage security. A security metric, as a standard of measurement for power system security, producting a set of discrete values rather than binary values, is employed. In order to analyze the above two problems, reactive power/voltage control problem and static security assessment problem, in an integrated fashion for real-time operations, a new organizational structure, called an A-team, is adopted. An A-team is an organization for agents which ale all autonomeus, work in parallel and communicate asynchronously, which is well-suited to the development of computer-based, multi-agent systems for operations. This A-team based approach, although it is still in the beginning stage, also has potential for handling other difficult power system problems.

• Journal of the Society of Disaster Information
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• v.14 no.3
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• pp.360-366
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• 2018

Purpose: This study operation of Joint inter-agency Chemical Emergency Preparedness Center and contribute to the reduction of chemical accidents that occur continuously. Method: The Joint inter-agency Chemical Emergency Preparedness Center functions and Chemical accident statistics data of the ('13~'17) were utilized. Results: The number of chemical accidents is decreasing from 113 in '15, 78 in '16, 87 in '17(latest five years 469 chemical accidents). The Joint inter-agency Chemical Emergency Preparedness Center is located in the industrial complex that handling a large amount of chemical, and performs functions such as prompt response, probation & investigation, accident prevention training, safety patrol. It is believed that it contributes to the decreasing of chemical accident by local control accident prevention function. Conclusion: Decreasing the safety management according to the Chemicals control act('15.1.1). The Joint inter-agency Chemical Emergency Preparedness Center('14.1 set up manage organization), which is operated as a mission to prepare respond to chemical accidents, plays a role.

• Journal of Food Hygiene and Safety
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• v.34 no.2
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• pp.199-204
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• 2019

This study aimed to generate a probability distribution model based on temperature data of frozen food storage facility as input variables for microbial risk assessment (MRA). We visited 8 food-handling businesses to collect temperature data from their cold storage warehouses. The overall mean temperature inside the storage facilities was $-20.48{\pm}3.08^{\circ}C$, with 20.4% of the facilities having above $-18^{\circ}C$, with minimum and maximum temperature values of -10.3 and $-25.80^{\circ}C$ respectively. Temperature distributions by space locations of natural and forced convection were $-22.57{\pm}0.84$ and $-17.81{\pm}1.47^{\circ}C$, $-22.49{\pm}1.05$ and $-17.94{\pm}1.44^{\circ}C$, and $-22.68{\pm}1.03$ and $-18.08{\pm}1.42^{\circ}C$ in the upper (2.4~4 m), middle (1.5~2.4 m), and lower (0.7~1.5 m) shelves, respectively. Probability distributions from the temperature data were obtained using the program @RISK. Statistical ranking was determined using goodness of fit to determine the probability distribution model. Our results show that a log-normal distribution [5.9731, 3.3483, shift (-26.4281)] is most appropriate for relative MRA conduction.

• Clean Technology
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• v.28 no.2
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• pp.123-130
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• 2022

Nanoparticles are used in various fields such as chemistry, medicine, the environment, and information and communication. With the increasing use of engineered nanomaterials, exposure to nanoparticles is expected to increase in the workplace and the environmental media. However, while nanotechnology industries are expanding, research on the exposure assessment of nanomaterials to humans and the environment is only at a beginning stage. Especially, if nanoparticles with a size of 100 nm or less that are contained in nano-products are released unintentionally, they may pose potential risks to the human body through breathing or skin exposure. Therefore, in this work, the possibility of potential exposure of nanoparticles moving from the laboratory to the office was confirmed, and nanoparticle safety guidelines are proposed. A nano-collector was used to detect nanoparticles in the atmosphere, and through use of a scanning mobility particle sizer it was found that nanoparticle concentrations in the laboratory and the office tended to be similar. On the assumption that nanoparticles attached to a lab-coat move out of the laboratory, a lab-coat to which nanocarbon black was attached was shaken and the concentration of the remaining particles on the lab-coat determined. The results confirmed that sufficient amounts of nanoparticles attached to the lab-coat could move from the laboratory to the office along the path of a researcher; thus, safety guidelines for the handling of lab-coat nanoparticles are required.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.5
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• pp.470-478
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• 2023

All people have human rights that should be protected, and today, the importance of protecting human rights is emphasized in all areas of society. The industry is also carrying out activities to protect the human rights of workers, such as implementing human rights education for human rights management and preparing a response system for human rights violations. However, due to the closed environment and special working conditions, seafarers on board are often placed in a blind spot in human rights protection. In particular, a number of cases of human rights violations concerning beginner seafarers, including cadets, have been identified, and relevant research is insufficient compared to other occupational groups. Jobs that restrict basic human rights cannot be envied by anyone. In this study, implications and problems were derived based on the results of a human rights survey of cadets, and cases of human rights violations, and improvement measures were proposed. The cadets had a very negative perception of human rights violations before boarding. However, it was found that their perception changed after boarding. It was confirmed that cadets have unnecessary fears and concerns before boarding. Improvement measures include the establishment of a legal system for the status of cadets, measures to alleviate non-physical human rights violations, improvement of human rights violations handling procedures and response systems, and enhancing the effectiveness of human rights education.

• Journal of agricultural medicine and community health
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• v.35 no.4
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• pp.417-427
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• 2010

Objectives: This study was conducted to develop a Korean version of the Participatory Action Oriented Training (PAOT) program and training materials for improvement of agricultural working environments. Methods: The PAOT manual and checklist were developed on the basis of the original English version of the training materials, a questionnaire survey of agricultural health and safety professionals, and a brainstorming conference. Good example pictures were collected through visits to agricultural workers' houses, and an easily understandable picture was drawn by an animation specialist. A PAOT action manual and five types of action checklists were developed for use in different agricultural environments. Each action checklist contained six categories and 38 items of agricultural health and safety principles; the six categories were material storage and handling, work stations and tools, machine safety, physical environment, working schedule and organization, and basic health and safety management. Incorporating these training materials, a one-day Korean PAOT program was developed. Results: Among 307 candidate agricultural workers from four rural Korean villages, 94 workers (59 males, 35 females) participated in a PAOT from July 2007 to Oct 2008. The PAOT program was successful and the mean self-estimated satisfaction score of the participants was greater than 90%. Conclusions: A Korean PAOT program and training materials were successfully developed and applied to Korean agricultural workers. Although more studies are needed, it is expected that PAOT will greatly contribute to the improvement of agricultural working conditions and health and safety through the use of agricultural workers' self initiatives.