• Title/Summary/Keyword: Investigation environment factor

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Seismic capacity evaluation of fire-damaged cabinet facility in a nuclear power plant

  • Nahar, Tahmina Tasnim;Rahman, Md Motiur;Kim, Dookie
    • Nuclear Engineering and Technology
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    • v.53 no.4
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    • pp.1331-1344
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    • 2021
  • This study is to evaluate the seismic capacity of the fire-damaged cabinet facility in a nuclear power plant (NPP). A prototype of an electrical cabinet is modeled using OpenSees for the numerical simulation. To capture the nonlinear behavior of the cabinet, the constitutive law of the material model under the fire environment is considered. The experimental record from the impact hammer test is extracted trough the frequency-domain decomposition (FDD) method, which is used to verify the effectiveness of the numerical model through modal assurance criteria (MAC). Assuming different temperatures, the nonlinear time history analysis is conducted using a set of fifty earthquakes and the seismic outputs are investigated by the fragility analysis. To get a threshold of intensity measure, the Monte Carlo Simulation (MCS) is adopted for uncertainty reduction purposes. Finally, a capacity estimation model has been proposed through the investigation, which will be helpful for the engineer or NPP operator to evaluate the fire-damaged cabinet strength under seismic excitation. This capacity model is presented in terms of the High Confidence of Low Probability of Failure (HCLPF) point. The results are validated by the proper judgment and can be used to analyze the influences of fire on the electrical cabinet.

Harmony Matters in Alarm Design: Investigating the Impact of Consonance on Alarm System

  • Ilgang Mukko Lee;Yunsun Alice Hong;Juhyun Jay Lee;Kwanghee Han
    • International Journal of Advanced Culture Technology
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    • v.11 no.4
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    • pp.406-416
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    • 2023
  • Alarm system performance is a critical aspect of safety. While existing research has extensively examined the influence of acoustic attributes on alarm performance, consonance's impact remains largely uncharted territory. This study bridges this research gap by investigating the effect of consonance on alarm systems. We extend our investigation to encompass not only the sound characteristics of the alarm but also the acoustic qualities of the surrounding environment, recognizing their potential impact on alarm efficacy. Prior studies consistently link consonance to annoyance levels, resulting in a negative user experience. Thus, we explore the relationship between consonance and alarm system performance, with a particular focus on modulating annoyance as an explanatory factor. Utilizing an oddball paradigm, we categorized standard and oddball sounds into consonant and dissonant types, creating four sound combinations. Participants were asked to respond to the irregularly presented oddball sounds while ignoring the constantly presented standard sounds. Our results reveal significant differences between groups, with the Standard Consonant/Oddball Dissonant (SC/OD) group displaying notably slower response times than the Standard Dissonant/Oddball Consonant (SD/OC) group. This reaction time variation aligns with differences in annoyance levels, as the SC/OD group reports higher annoyance, suggesting that reaction time discrepancies may be linked to increased arousal due to heightened annoyance.

Intestinal Parasitic Infections and Environmental Water Contamination in a Rural Village of Northern Lao PDR

  • Ribas, Alexis;Jollivet, Chloe;Morand, Serge;Thongmalayvong, Boupha;Somphavong, Silaphet;Siew, Chern-Chiang;Ting, Pei-Jun;Suputtamongkol, Saipin;Saensombath, Viengsaene;Sanguankiat, Surapol;Tan, Boon-Huan;Paboriboune, Phimpha;Akkhavong, Kongsap;Chaisiri, Kittipong
    • Parasites, Hosts and Diseases
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    • v.55 no.5
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    • pp.523-532
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    • 2017
  • A field survey studying intestinal parasites in humans and microbial pathogen contamination at environment was performed in a Laotian rural village to identify potential risks for disease outbreaks. A parasitological investigation was conducted in Ban Lak Sip village, Luang Prabang, Lao PDR involving fecal samples from 305 inhabitants as well as water samples taken from 3 sites of the local stream. Water analysis indicated the presence of several enteric pathogens, i.e., Aeromonas spp., Vibrio spp., E. coli H7, E. coli O157: H7, verocytotoxin-producing E. coli (VTEC), Shigella spp., and enteric adenovirus. The level of microbial pathogens contamination was associated with human activity, with greater levels of contamination found at the downstream site compared to the site at the village and upstream, respectively. Regarding intestinal parasites, the prevalence of helminth and protozoan infections were 68.9% and 27.2%, respectively. Eight helminth taxa were identified in fecal samples, i.e., 2 tapeworm species (Taenia sp. and Hymenolepis diminuta), 1 trematode (Opisthorchis sp.), and 5 nematodes (Ascaris lumbricoides, Trichuris trichiura, Strongyloides stercoralis, trichostrongylids, and hookworms). Six species of intestinal protists were identified, i.e., Blastocystis hominis, Cyclospora spp., Endolimax nana, Entamoeba histolytica/E. dispar, Entamoeba coli, and Giardia lamblia. Questionnaires and interviews were also conducted to determine risk factors of infection. These analyses together with a prevailing infection level suggested that most of villagers were exposed to parasites in a similar degree due to limited socio-economic differences and sharing of similar practices. Limited access to effective public health facilities is also a significant contributing factor.

An Approach to Drought Vulnerability Assessment using TOPSIS Method (TOPSIS을 적용한 가뭄취약성 평가 방법에 관한 연구)

  • LEE, Chang-Woo;SHIN, Hyung-Jin;KWON, Min-Sung;LEE, Gyu-Min;NAM, Sang-Hyeok;KANG, Mun-Sung
    • Journal of the Korean Association of Geographic Information Studies
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    • v.22 no.4
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    • pp.102-115
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    • 2019
  • This study aims to establish and apply a drought vulnerability assessment plan including various factors related to drought. The evaluation technique consisted of three stages: evaluation factor and weight selection, evaluation data database construction, evaluation data and weight combination, and Delphi investigation method was applied to evaluation factor and weight selection. As the evaluation method, the TOPSIS method, which is a widely used MCDM method, was used. The results of the drought vulnerability assessment were applied to the administrative districts of Sigun-gu, Korea from March 2016 to September 2019. As a result of the evaluation, drought vulnerable areas were identified in Chungcheongbuk-do, Gyeongsangnam-do, and Jeollanam-do, and it was analyzed that it is necessary to establish drought response plans for these areas.

A Comparison on the Factors Influencing Customer Values in Electronic Commerce between Korea and China (전자상거래 고객가치 요인의 한·중 비교)

  • Lee, Hyun-Kyu;Han, Jae-Ho
    • The Journal of Information Systems
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    • v.21 no.4
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    • pp.155-183
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    • 2012
  • Means-Ends Network model was used to identify factors of means objective(means supplied by vendor) and fundamental objectives(purchasing motivations) for purchasing decision-making structure and dimensions of customer values on purchasers of internet shopping mall in Korea and China. In Means-Ends Network 6 factors(shopping travel, shipping assurance, vendor trust, online payment, product choice, and recommender systems) were found as a means objectives and 3 factors(shopping convenience, internet environment, customer support) as a fundamental objectives of shopping. However the results of hypotheses test for Means-Ends Network show some important differences between two countries. Something important to notice here is that Chinese customers shopping in China recognize shipping assurance factor and vendor trust factor as important factors satisfying all fundamental objectives unlike as in the case of our country. As these two factors are attribution factors responsible to the sellers, it is identified that customers do not trust the sellers and sellers have not met the expectations of customers. Therefore, these results show that the seller efforts assuring the reliability of the seller themselves, such as conducting its own compensation scheme are more important rather than the establishment of the guarantee institution to guarantee reliability and delivery assurance of sellers and implementation of legal and institutional apparatus such as the settlement of e-commerce licence system. Though this study presents such an important marketing implications, it can be pointed out that the limits are this research was done on the general Internet shopping malls without considering the Internet shopping mall types of diversity, the survey was designed around the student samples for convenience of the investigation because it was an international survey and the collected data has been limited to the western coast cities, such as China's Beijing, Shanghai, and Dalian.

Development and Validation of Physical Education Teaching Anxiety Scale for Preservice Special Teacher (예비특수교사의 체육교수불안 척도 개발 및 타당화)

  • Lee, Yong-Kuk
    • 한국체육학회지인문사회과학편
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    • v.57 no.3
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    • pp.375-389
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    • 2018
  • This study aims to development and validation a tool to measure physical education teaching anxiety(PETA) among preservice special teacher. In order to achieve this study purpose, first, the preliminary items for measurement scale were collected through open-ended questions and were developed by inductive content analysis from the 100 preservice special teacher. Second, investigation for construct validity was conducted on exploratory factor analysis from the 100 preservice special teacher. Third, in the final process, verify exernal validity was conducted by confirmatory factor analysis and t-test from the 300 presevice special teacher. As a result, the measurement scale of physical education teaching anxiety(PETA) among preservice special teacher consists of 4 main factors with 14 items: pedagogical content knowledge(n=4), understanding students(n=4), class environment(n=3), class management(n=3) factors and this scale has enough suitability.

A Study for Improving the Traffic Accident Management System with regard to the Driver's Human Factor (운전자 인적요인을 고려한 교통사고 조사양식 개선방안 연구)

  • Ju Seok Oh;Soon Chul Lee
    • Korean Journal of Culture and Social Issue
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    • v.16 no.3
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    • pp.267-287
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    • 2010
  • This study aimed to improve the Traffic Accident Management System's validity and reliability, so the system could help classify and judge the human factors that correlate with traffic accidents. We took traffic accident research and analysis systems of United States and United Kingdom and certain related, former studies into account in building our test system. Next, we used the test system's criteria to re-analyze 502 Gyeonggi province accident records from 2008. We compared the results to existing systems' results to verify the test system's validity and reliability. These results indicated the necessity of removing some uncertain items from the existing systems and adding in some new items from the test system. This should help improve understanding of what happens at traffic accident scenes and of the sources of drivers' abnormal, reckless behavior. We introduce suggestions for improving the Traffic Accident Management System and research concepts for further studies.

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Ecological diagnosis of the Gongjicheon water system using length-weight relationship and condition factor(K) of population of the Zacco platypus (피라미 개체군의 length-weight relationship 및 condition factor(K)를 이용한 공지천수계의 생태적 진단)

  • Lee, Kwang-Yeol;Jang, Hara;Yun, Youngjin;Park, Seungchul;Kim, Joon Chul;Lee, Jaeyong;Choi, Jaeseok
    • Journal of Environmental Impact Assessment
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    • v.23 no.2
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    • pp.137-149
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    • 2014
  • The purpose of this study is to investigate the dynamics of the Zacco platypus population among streams in the Gongjicheon water system, Korea from December 2010 to October 2011. In this study, fish fauna was collected 27 Species belonged to 9 Families. The legal protection species, such as a natural monument and endangered species was not collected. Korean endemic species was collected 6 species including to Z. koreanus. The ratio of Korean endemic species was 22.6%, and it was lower than 51.3% that average of Korean endemic species in the Hangang water system. About these status, we considered that Gongjicheon water system had lost of the unique characteristics of the Hangang water system by the anthropogenic disturbances. The result of analysis to length-weight relationship and condition factor(K) of Z. platypus population in the Gongjicheon water system, the regression coefficient value(b) to indication of growth degree of the population was 3.04 and the slope of the condition factor(K) to indication of corpulency had positive value, respectively. These results seems to be that the Z. platypus population is maintained to a little unstably. In addition, the values of the degree of growth and corpulence were very low than the other natural streams in the Hangang water system, so it considered that the many artificially stress factors are occurred in this study area. These results are similar to Fish Assessment Index(FAI) in the assessment for health of aquatic ecosystem. Therefore, we are considered to require precise investigation and sustained monitoring for the restorations of stream ecosystem in the Gongjicheon water system.

Distribution Characteristics of PM10 and Heavy Metals in Ambient Air of Gyeonggi-do Area using Statistical Analysis (통계분석을 이용한 경기도 대기 중 미세먼지 및 중금속 분포 특성)

  • Kim, Jong Soo;Hong, Soon Mo;Kim, Myoung Sook;Kim, Yo Yong;Shin, Eun Sang
    • Journal of Korean Society for Atmospheric Environment
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    • v.30 no.3
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    • pp.281-290
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    • 2014
  • This study was conducted to evaluate the distribution characteristics of $PM_{10}$ and heavy metals concentrations in the ambient air of Gyeonggi-do area by region and season from February, 2013 to March, 2014. The regression model for the prediction of formation characteristics and contamination degree of $PM_{10}$ and heavy metals by correlation analysis and regression analysis for using the multivariate statistical analysis was also established. The main wind direction during the investigation period was South East (SE) and West South West (WSW) winds, and the concentration of $SO_2$ at Ansan with industrial region showed 1.6 times higher than Suwon, Euiwang with residential region. The concentrations (median) of Pb, Cu and Ni at Ansan showed 3.2~4.5, 1.9~2.2 and 1.7~2.6 times respectively higher than those at Suwon. By the seasonal concentration variation, the concentrations of $PM_{10}$, Pb, Fe and As in winter and spring (December to May) showed 1.7, 1.9, 1.9 and 2.7 times respectively higher than those in summer and fall (June to November). As, Fe and $PM_{10}$ had a big difference by the seasonal factors, and Cu and Ni were evaluated to be influenced by the regional factors. From the results of correlation analysis among the target items, the correlation coefficient of PM and Mn had 0.82 (p/0.01) and that of Fe and Mn had 0.82 (p/0.01), which showed high correlation. And the correlation coefficients for $SO_2$ and Pb, CO and $PM_{10}$ were 0.66 (p/0.01) and 0.62 (p/0.01) respectively. The multiple linear regression models for $PM_{10}$, Pb, Cu, Cr, As, Ni, Fe and Mn were established by independent variables of CO, $SO_2$ and meteorological factors (wind speed, relative humidity). In the regression models, independent variable $SO_2$ was in cause-and-effect relationship with all dependent variables, and $PM_{10}$, Fe and Mn were influenced by CO and wind speed, and Pb, Cu, Ni and As had a main factor of $SO_2$.

Study on the Improvement of a Special Fire Police Judicial Police System (소방특별사법경찰제도의 문제점에 따른 개선방안 연구)

  • Park, Hyeong-Jin;Kim, Jung-Rae;Kim, Jong-Buk;Cha, jin;Kwon, Hyun-Seok;Lee, Si-Young
    • Fire Science and Engineering
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    • v.32 no.5
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    • pp.77-86
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    • 2018
  • In recent years, the high growth of the Korean society has led to the development of large and small incidents and accidents, while safety regulations, such as the firefighting sector, have been strengthened with the expectation of people desiring safety. This study surveyed the problems and improvement plan of the current operation centered on the fire service public officers in Gyeonggi-do and Gangwon. As a result of the main research, it is necessary to arrange and carry out excellent investigative manpower, such as lawyers and professional career veterans in the fire department, metropolitan city and provincial firefighting headquarters, and frontline fire departments. In particular, it was suggested that a special task force should be established and set up in the above agency, and the planning investigation and enforcement work should be solved through subdivision of the fire special enforcement officer tasks, and the judicial cases that are difficult to be handled by the local fire station. In future research, it will be necessary to study the field of fire - fighting specialists' needs for more specialized education and various disaster field experiences.