• Applied Chemistry for Engineering
• /
• v.34 no.6
• /
• pp.603-607
• /
• 2023

Aqueous film forming foam (AFFF) is a critical fire suppression agent used in combating hydrocarbon fires. This type of fire suppressant is highly effective due to its ability to form a protective film, dissipate heat, inhibit combustion, and utilize a blend of chemical substances to extinguish fires. While these properties offer significant advantages in responding to hydrocarbon fires, AFFF is distinct in its deployment as it is dispensed in the form of foam. Therefore, the rheological analysis of AFFF foam using a rheometer plays a crucial role in predicting the spray characteristics of AFFF for combating hydrocarbon fires, and this is closely associated with effective fire suppression. In this study, we conducted rheometer experiments to confirm the non-Newtonian behavior (shear-thinning) of AFFF foam and obtained data on the form's stability. These experimental data are expected to contribute to enhancing the efficiency of fire suppression systems utilizing AFFF.

• The Transactions of the Korea Information Processing Society
• /
• v.13 no.10
• /
• pp.475-480
• /
• 2024

As Internet of Things (IoT) technology is being used in all industries, the importance of secure and convenient firmware update technology is increasing. However, conventional FOTA (Firmware Over-The-Air) technology has a problem because the security is weak when updating firmware with a single path, and strong encryption technology cannot be utilized. Therefore, this study proposes a secure FOTA (S-FOTA) mechanism for lightweight IoT and adaptive S-FOTA ARQ (Automatic Repeat Request) mechanism. This adaptive S-FOTA ARQ mechanism considers the case where the original file cannot be recovered because of the increase in lost files due to the congested channel state and compares and analyzes the conventional method in terms of security, complexity, and transmission speed. Experimental results show that S-FOTA with 40 encrypted files reduced the attacker's attack success rate by at least 62.58% and up to 99.99%, and S-FOTA with 40% of the total number of encrypted file segments takes at least 996.39% more time on average and up to 3374.99% more time than conventional FOTA. In addition, the transmission speed of the adaptive S-FOTA ARQ mechanism was at least 63.16% and up to 2736.36% higher than that of the conventional S-FOTA, and at least 53.89% and up to 70.89% higher than that of the conventional ARQ mechanism.

• Journal of Food Hygiene and Safety
• /
• v.34 no.3
• /
• pp.251-262
• /
• 2019

In this study, we analyzed Korean dietary habits with food intake data from the Korea National Health and Nutrition Examination Survey (KNHANES) and the Korea Centers for Disease Control and Prevention and we proposed a set of management guidelines for future Korean dietary habits. A total of 839 food items (1,419 foods) were analyzed according to the food catagories in "Food Code", which is the representative food classification system in Korea. The average total daily food intake was 1,585.77 g/day, with raw and processed foods accounting for 858.96 g/day and 726.81 g/day, respectively. Cereal grains contributed to the highest proportion of the food intake. Over 90% of subjects consumed cereal grains (99.09%) and root and tuber vegetables (95.80%) among the top 15 consumed food groups. According to the analysis by item, rice, Korean cabbage kimchi, apple, radish, egg, chili pepper, onion, wheat, soybean curds, potato, cucumber and pork were major (at least 1% of the average daily intake, 158.6 g/day) and frequently (eaten by more than 25% of subjects, 5,168 persons) consumed food items, and Korean spices were at the top of this list. In the case of kimchi, the proportion of intake of Korean cabbage kimchi (64.89 g/day) was the highest. In the case of alcoholic beverages, intake was highest by order of beer (63.53 g/day), soju (39.11 g/day) and makgeolli (19.70 g/day), and intake frequency was high in order of soju (11.3%), beer (7.2%), and sake (6.6%). Analysis results by seasonal intake trends showed that cereal grains have steadily decreased and beverages have slightly risen. In the case of alcoholic beverage consumption frequency, some kinds of makgeolli, wine, sake, and black raspberry wine have decreased gradually year by year. The consumption trend for kimchi has been gradually decreasing as well.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.17 no.4
• /
• pp.399-405
• /
• 2011

Recently, the navigation risk is increasing significantly with growth of marine traffic volume and construction of marine facilities, water bridges, port development and marine wind farm etc. To reduce this kinds of risk, Ministry of Land, Transport and Maritime Affairs enacted a new law called MSA(Maritime Safety Audit) as a comprehensive maritime traffic safety management scheme in order to ensure safety improvements from the early planning stage to post managing of the development which affect the maritime traffic environment. MSA as a tool for improving maritime traffic safety is a formal safety assessment in the existing or future ship's fairway by an independent audit team. It examines the potential hazards of maritime traffic safety, if necessary, and is to ensure the implementation of appropriate safety measures. The object of this paper is to comprehensively evaluate the achievements and implementation problems of MSA about the 2 years, to define the fundamental problems of MSA by conceptualizing and analyzing MSA limits. MSA requires further examination about the introduction of screening and scoping in order to increase the efficiency and objectivity. It will be required the measures concerning policies directions as a tool for planning process for project owner. It will lead to right understanding concerning audit scheme and used in various ways such as amendments to related law.

• The Journal of the Korea Contents Association
• /
• v.11 no.7
• /
• pp.437-447
• /
• 2011

This study will compare and analyze the effect of satisfaction of security needs on life satisfaction according to sociodemographic features and will find the factors of security needs satisfaction and life satisfaction. a total of three humdred questionnaires was distributed to male and female who live in Seoul(Gang-dong, Gang-sue, Songpa-gu and Gand-buk) in Aug. and Sept., 2010 and over nineteen years old. Except making the wrong questionnaires, total questionnaires was sampled from 259 questionnaires using judgment sampling method after selecting. Data analysis be used by SPSSWIN 18.0 Version. The validity and reliability of questionnaires are verified for factorial analysis and reliability analysis and also T test and F test are used for finding for differences of life satisfaction and satisfaction of security needs. And, this study is tested the regression analysis for the effects on the life satisfaction and satisfaction of security. Utilizing CCTV on the Life Satisfaction, this study were drawn the conclusions as following. First, the satisfaction of security needs as demographic characteristics have the part of the difference. the result shows to different psychological needs as educational level at the group less than college graduates. Second, the result of satisfaction of security as demographic characteristics is significantly higher in the male group and life satisfaction as education is significantly higher in more than college graduates. Third, the satisfaction of security needs of citizens through the CCTV effects to life satisfaction. environmental needs and information needs are as high as life satisfaction.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.1
• /
• pp.577-586
• /
• 2018

In this study, traffic safety technology was developed for rural areas by reviewingthe relevant literature and data from the Traffic Accident Analysis System for the Chungcheong region.The goal is to reduce traffic accidents in small regional cities and rural areas in Korea. A road shoulder recognition light was developed to fit the pedestrian characteristics of the people using transportation in rural areas. It also minimizes damage to crops due to light pollution from traffic lights and street lights, and it supplements problems of damage from collision with vehicles and agricultural machines. The efficiency of the technology developed in this study was verified by comparing and analyzing the number of traffic accidents and the saved cost before and after its installation. A test bedwas established based on rural areas and is being evaluated for its applicability and effectiveness. It is expected that the reliability of such facilities could be improved through continuous studies, data collection, and analysis.

• Journal of Korean Society of Transportation
• /
• v.32 no.5
• /
• pp.431-440
• /
• 2014

According to the State Safety Program (SSP) of the International Civil Aviation Organization (ICAO), it is essential to establish and manage Safety Performance Indicators (SPIs) which are used for monitoring the safety performance to achieve the national aviation safety goal. There have been enormous efforts to develop the framework of SPIs by considering the current status for each country. In case of Republic of Korea, however, there has been limited research and policy projects related to the framework for SPIs. Furthermore, Korea has used identical SPIs since the SSP was legislated in 2008. With this background, this research is, as part of strategy for the state level of SPI development, the study cases of advanced aviation countries for SPI development plans, such as the European Aviation Safety Agency (EASA) of the EU, the Civil Aviation Authority (CAA) of the UK, the Finish Transport Safety Agency (FTSA) of the Finland and the Federal Aviation Administration (FAA) of the U.S. The comparison between the foreign and domestic policies for SPI development strategies are provided in the conclusion of this study. The results and analyses of the case studies performed in this research will be helpful to provide some valuable development strategies for further SPI research in Korea.

• Korean Journal of Construction Engineering and Management
• /
• v.14 no.4
• /
• pp.3-14
• /
• 2013

Recently, as the size of construction projects is getting bigger and higher, construction disasters have been being serious such as death, also it is hard to manage efficiently since there are plenty of informations about safety management. Thus on the spot & real time safety management is required and one of the ways to support these needs, conjunction with Information Technology(IT) has been being noticed. Accordingly, Personal Digital Assistant(PDA), Palmtop Computer and Tablet Personal Computer and so on have been adopted. However another inefficient sides are showed up such as limitation of equipment(weight, inconvenience of control and others). Meanwhile, exchanging and processing data are improved at wide area due to advance of mobile communication and introduction of smart mobile, which is a simple and convenient, is a proven at many aspects. In this research, to support effective safety management, the framework is realized in connection with smart mobile with finding the problems of safety management and deriving demands. Two smart mobile applications, which are Safety Management application and Safety Guideline application, enable that safety management in real time, less re-work and using safety information.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.23 no.1
• /
• pp.67-72
• /
• 2017

This study developed an electric power propulsion personal watercraft by combining a battery and an electric system from the domestic automobile industry with water motorcycle from marine leisure industry in a convergence of technology. It also developed a safety inspection plan and type approval standard for personal watercraft that use electric power propulsion. For the registration and production of the electric power PWC (Personal Watercraft), a safety inspection standard (draft) and type approval standard (draft) have been established. PWC that use this electric power propulsion certification standard have been divided into two categories according to the use of gasoline engines as related to the ship's electrical system. The contents of these safety inspections standards is divided into 7 categories, and their purpose is to confirm the facilities used for the safe operation of PWC. Type approval is divided into 7 categories and is intended to ensure the safe production of PWC. This is basic data can be used to establish criteria for safety inspection and type approval of electric power propulsion vessels and to guide the production of the environmentally friendly PWC in Korea.

• Journal of Korean Home Economics Education Association
• /
• v.32 no.1
• /
• pp.127-143
• /
• 2020

The purpose of this study is to develop the clothing safety teaching/learning plan in Home Economics based on the health belief model and to examine the effects of the course using the developed teaching/learning plan on the health belief. Based on ADDIE model, 6 clothing safety teaching/learning plans were developed by applying the health belief model. They consisted of three learning factors of 'harmful substances that can be exposed during the production, wear, wash, and storage of clothes and textile products', 'environment friendly fibers' and 'natural detergents'. Then they were implemented on 7 classes in middle school located in Gyeonggi-do Province from August 20 to September 7 in 2018. The health beliefs data collected before and after the course were analyzed with paired t-test with SPSS/win. As a result, the perceived threat(combination of perceived severity and perceived susceptibility), the perceived benefit, and the self-efficacy were significantly improved. And the perceived barrier was significantly reduced. In conclusion, the home economics clothing safety education course using the health belief model was meaningful as the safety education to enable middle school students to practice safe clothing life from harmful substances. The results of this study are expected to be helpful for activating safety education in home economics.