• Title/Summary/Keyword: Hypothetical Model

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3-Dimensional Analysis of the Steam-Hydrogen Behavior from a Small Break Loss of Coolant Accident in the APR1400 Containment

  • Kim Jongtae;Hong Seong-Wan;Kim Sang-Baik;Kim Hee-Dong;Lee Unjang;Royl P.;Travis J. R.
    • Nuclear Engineering and Technology
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    • v.36 no.1
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    • pp.24-35
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    • 2004
  • In order to analyze the hydrogen distribution during a severe accident in the APR1400 containment, GASFLOW II was used. For the APR1400 NPP, a hydrogen mitigation system is considered from the design stage, but a fully time-dependent, three-dimensional analysis has not been performed yet. In this study GASFLOW code II is used for the three-dimensional analysis. The first step to analysis involving hydrogen behavior in a full containment with the GASLOW code is to generate a realistic geometry model, which includes nodalization and modeling of the internal structures such as walls, ceilings and equipment. Geometry modeling of the APR1400 is conducted using GUI program by overlapping the containment cut drawings in a graphical file format on the mesh view. The total number of mesh cells generated is 49,476. And the calculated free volume of the APR1400 containment by GASFLOW is almost the same as the value from the GOTHIC modeling. A hypothetical SB-LOCA scenario beyond design base accident was selected to analyze the hydrogen behavior with the hydrogen mitigation system. The source of hydrogen and steam for the GASFLOW II analysis is obtained from a MAAP calculation. Combustion pressure and temperature load possibilities within the compartments used in the GOTHIC analysis are studied based on the Sigma-Lambda criteria. Finally the effectiveness of HMS installed in the APR1400 containment is evaluated from the point of severe accident management

Awareness of the Fifth Grade Students about the Natural Environment Preservation (초등학교 5학년 학생들의 자연 환경 보존에 대한 인식)

  • Shim, Wang-Geun;Moon, Byoung-Chan
    • Hwankyungkyoyuk
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    • v.22 no.1
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    • pp.83-96
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    • 2009
  • This paper is intended to investigate the awareness of the elementary school students about the natural environment preservation. For this purpose, 21 elementary school students from the 5th grade of elementary school located in Gwangju city were selected. Especially, we focused on the students' conceptions related to 1) the environments, 2) the safe national land development activity to face several natural disasters and 3) the environmental preservation with the national land development. To evaluate the change of students' conceptions for the national land development, the students were also participated in establishing the plan of the national land development using the model of the natural environment after learning in detail about the natural environments. The results of this study showed that most of the students recognized the concept of the environments as a simple knowledge itself and pollution rather than the protection of environment. In the course of the safe national land development activity to face several natural disasters, the students expressed standardized answer indicating the knowledge based thinking of the environments. According to the results of the environmental preservation with the national land development and the hypothetical project of the national land development, the students did not have enough knowledge for the natural environment preservation although they had understanding of natural disasters and environmental preservation. Therefore, it is necessary to stress affirmative concept for the environment related to the preservation of natural environment. Also we need to develop the syllabus, which is related to the environmental studies, in the elementary educational program leading students to participate in the environmental preservation with the national land development reasonably and practically.

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Investigation of Impacts of Truck Lane Restrictions on Multilane Highways Using Micro Traffic Simulation (미시적 시뮬레이션을 이용한 화물차 차로이용제한 영향분석)

  • Yang, Choong-Heon;Son, Young-Tae;Kwon, Yong-Suk
    • International Journal of Highway Engineering
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    • v.9 no.4
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    • pp.75-82
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    • 2007
  • This study was performed to investigate impacts of truck lane restrictions on multilane highways on traffic flow variables such as average speed, the frequency of lane changes, and change in traffic volume and also to verify whether or not different lane restriction scenarios were proper. Two types of hypothetical highway networks and OD demands were developed for traffic simulation models in order to conduct the experimental study. Three types of scenarios were also developed according to the number of restricted lanes for trucks. The PARAMICS microscopic traffic simulation software package was used as the primary analytical tool. Statistical analysis was conducted with simulation outputs. Results showed that truck lane restrictions may lead to positive impacts on traffic flow on multilane highways. In addition, this study demonstrated that the number of restricted lanes can be very an important factor to lead successful implementation of truck lane restrictions.

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Expressed Sequence Tag Analysis of the Erythrocytic Stage of Plasmodium berghei

  • Seok, Ji-Woong;Lee, Yong-Seok;Moon, Eun-Kyung;Lee, Jung-Yub;Jha, Bijay Kumar;Kong, Hyun-Hee;Chung, Dong-Il;Hong, Yeon-Chul
    • Parasites, Hosts and Diseases
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    • v.49 no.3
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    • pp.221-228
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    • 2011
  • Rodent malaria parasites, such as Plasmodium berghei, are practical and useful model organisms for human malaria research because of their analogies to the human malaria in terms of structure, physiology, and life cycle. Exploiting the available genetic sequence information, we constructed a cDNA library from the erythrocytic stages of P. berghei and analyzed the expressed sequence tag (EST). A total of 10,040 ESTs were generated and assembled into 2,462 clusters. These EST clusters were compared against public protein databases and 48 putative new transcripts, most of which were hypothetical proteins with unknown function, were identified. Genes encoding ribosomal or membrane proteins and purine nucleotide phosphorylases were highly abundant clusters in P. berghei. Protein domain analyses and the Gene Ontology functional categorization revealed translation/protein folding, metabolism, protein degradation, and multiple family of variant antigens to be mainly prevalent. The presently-collected ESTs and its bioinformatic analysis will be useful resources to identify for drug target and vaccine candidates and validate gene predictions of P. berghei.

A Study on Service Quality Satisfaction of Delivery Food App. of Korean and Chinese Customer (배달음식 앱의 서비스 품질 만족에 관한 연구 - 한국과 중국 소비자를 대상으로 -)

  • Hwang, Yuns-Sung;Park, Jae-kei;Wang, Yan;Seo, Yong-Mo;Rhee, Byungchae
    • Journal of the Korea Convergence Society
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    • v.9 no.12
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    • pp.239-250
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    • 2018
  • This study focus on analyzing the factors which influence the customer satisfaction of food delivery application and its degree of the influence on the quality satisfaction both with Korean and Chinese customers. For this purpose, the model of hypothetical structure was established through the mobile internet service quality measurement was called as MOBISQUAL. As a result, the Korean customers was confirmed that the fulfillment and playfulness as the subdimension of outcome quality both have a positive effect on customer satisfaction. And the Chinese customer was confirmed that the playfulness of outcome quality, personalization of contextual interaction, design, ease of use and security of servicescape quality affected customer satisfaction positively.

The Effect of Learners' Perception on Parents Academic Involvement on Career Maturity in Elementary School Students: Focusing on the Mediating Effects of Academic Self-Efficacy and School Adjustment (초등학생들이 지각한 부모의 교육적 관여가 진로성숙도에 미치는 영향: 학업적 자기효능감과 학교생활적응의 매개효과)

  • So, Yeon-Hee
    • Journal of vocational education research
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    • v.30 no.4
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    • pp.203-220
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    • 2011
  • This study examined the relationships between learners' perception on parents academic involvement, academic self-efficacy, school adjustment, and career maturity, and also to analyze the hypothetical structural equation model relating three independent variables to career maturity. The participants were 443 sixth grade children(218 boys and 225 girls). The findings are as follows. career maturity positively showed the highest correlations with learners' perception on parent academic involvement, and academic self-efficacy. The findings revealed that learners' perception on parent academic involvement indirectly influenced career maturity mediated by academic self-efficacy and school adjustment. Furthermore, school adjustment displayed the highest direct effect on career maturity, whereas learners' perception on parent academic involvement showed the highest indirect effect on career maturity. It was discussed to develop and mange career program, career education, and career counseling effectively for elementary school children.

Factors Affecting Radiation Protective Behaviors in Perioperative Nurses Applying the Theory of Planned Behavior: Path Analysis (계획된 행위이론을 적용한 수술실 간호사의 방사선 방어행위에 대한 영향요인: 경로분석)

  • Jang, Se Young;Kim, Hee Sun;Jeong, Seok Hee;Kim, Young Man
    • Journal of Korean Academy of Nursing
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    • v.53 no.2
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    • pp.222-235
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    • 2023
  • Purpose: The aim of this study was to identify the factors explaining protective behaviors against radiation exposure in perioperative nurses based on the theory of planned behavior. Methods: This was a cross-sectional study. A total of 229 perioperative nurses participated between October 3 and October 20, 2021. Data were analyzed using SPSS/WIN 23.0 and AMOS 23.0 software. The three exogenous variables (attitude toward radiation protective behaviors, subjective norm, and perceived behavioral control) and two endogenous variables (radiation protective intention and radiation protective behaviors) were surveyed. Results: The hypothetical model fit the data (χ2/df = 1.18, SRMR = .02, TLI = .98, CFI = .99, RMSEA = .03). Radiation protective intention (β = .24, p = .001) and attitude toward radiation protective behaviors (β = .32, p = .002) had direct effects on radiation protective behaviors. Subjective norm (β = .43, p = .002) and perceived behavior control (β = .24, p = .003) had direct effects on radiation protective intention, which explained 38.0% of the variance. Subjective norm (β = .10, p = .001) and perceived behavior control (β = .06, p = .002) had indirect effects via radiation protective intention on radiation protective behaviors. Attitude toward radiation protective behaviors, subjective norm, and perceived behavioral control were the significant factors explaining 49.0% of the variance in radiation protective behaviors. Conclusion: This study shows that the theory of planned behavior can be used to effectively predict radiation protective behaviors in perioperative nurses. Radiation safety guidelines or education programs to enhance perioperative nurses' protective behaviors should focus on radiation protective intention, attitude toward radiation protective behaviors, subjective norm, and perceived behavioral control.

A Study on the Overall Economic Risks of a Hypothetical Severe Accident in Nuclear Power Plant Using the Delphi Method (델파이 기법을 이용한 원전사고의 종합적인 경제적 리스크 평가)

  • Jang, Han-Ki;Kim, Joo-Yeon;Lee, Jai-Ki
    • Journal of Radiation Protection and Research
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    • v.33 no.4
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    • pp.127-134
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    • 2008
  • Potential economic impact of a hypothetical severe accident at a nuclear power plant(Uljin units 3/4) was estimated by applying the Delphi method, which is based on the expert judgements and opinions, in the process of quantifying uncertain factors. For the purpose of this study, it is assumed that the radioactive plume directs the inland direction. Since the economic risk can be divided into direct costs and indirect effects and more uncertainties are involved in the latter, the direct costs were estimated first and the indirect effects were then estimated by applying a weighting factor to the direct cost. The Delphi method however subjects to risk of distortion or discrimination of variables because of the human behavior pattern. A mathematical approach based on the Bayesian inferences was employed for data processing to improve the Delphi results. For this task, a model for data processing was developed. One-dimensional Monte Carlo Analysis was applied to get a distribution of values of the weighting factor. The mean and median values of the weighting factor for the indirect effects appeared to be 2.59 and 2.08, respectively. These values are higher than the value suggested by OECD/NEA, 1.25. Some factors such as small territory and public attitude sensitive to radiation could affect the judgement of panel. Then the parameters of the model for estimating the direct costs were classified as U- and V-types, and two-dimensional Monte Carlo analysis was applied to quantify the overall economic risk. The resulting median of the overall economic risk was about 3.9% of the gross domestic products(GDP) of Korea in 2006. When the cost of electricity loss, the highest direct cost, was not taken into account, the overall economic risk was reduced to 2.2% of GDP. This assessment can be used as a reference for justifying the radiological emergency planning and preparedness.

A Study on the Factors to Affecting Career Success among Workers with Disabilities (지체장애근로자의 직업성공 요인에 관한 연구)

  • Lee, Dal-Yob
    • Korean Journal of Social Welfare
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    • v.55
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    • pp.131-153
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    • 2003
  • This study was aimed at investigating important factors influencing career success among disabled workers. The current researcher scrutinized the degree to which variables and factors affect the career success and occupational turnover rates of the research participants. The participants in this study (n=837) were 374 workers with disabilities and 463 workers without disabilities. The results of this study can be summarized as follows: First, the results of factor analysis showed important categories of conceptual themes of career success. The initial conceptual factor model did not accord with the empirical one. Second, both research participant groups seemed to be influenced by their occupational types. However, all predictive variables excluding the wage rate and the average length of work years had significant impact on job success for the disabled work group, while all the variables excluding the frequency of advice and length of working years had significant impact on job success for the non-disabled worker group. Third, the turnover rate was significantly influenced by the age and the experience of turnover of the research participants. However, the number of co-workers was the strongest predictive variable for the worker group with disabilities, but the occupation choice variable for the worker group without disabilities. Fifth, as a result of verifying the hypothetical path model, it showed that the first model was somewhat proper and could predict the career success on both research participant groups. In conclusion, the following research implications can be suggested. The occupational type of research participants was one of the most important variables to predict the career success for both research participant groups.

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Field Applicability Evaluation of Foundation Combine with Footing and Pile by Model Test (모형실험을 통한 복합기초의 현장 적용성 평가)

  • Kim, Hak-Moon;Jang, Kyung-Jun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.8
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    • pp.3729-3744
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    • 2011
  • As the size of structures become larger by civil and architectural structures becoming large, deeply underground, and high-rise, the conditions of underground foundation vary according to the location that the lack of bearing capacity locally because of ununiform of foundation in some parts is frequent. Generally, when the foundation is not homogeneous, the acquisition of safety through applying the most conservative foundation method possible becomes the focus to secure the stability of the superstructures. It is considered as because of inability to verify the application and stability and application of construction of different foundations through an outlined review because of lack of study in case of different foundation of mixed use of direct foundation and pile foundation. Therefore, through measurement interpretation of the different foundation in which the direct foundation and pile foundation are mixed in use, the grounds in which the hypothetical bearing capacity changes dramatically was modeled to evaluate the applicability of different foundations. Also, based on the results of measurement interpretation, various foundations are created by using plaster, Joomunjin standard soil, and rubble to conduct an indoor model test to compare and analyze the movement of pile foundation and different foundations. Based on such research results, the stability and applicability of the different foundations which is more efficient and economical than the existing foundations in case of grounds in which the bearing capacity changes dramatically by comparing and analyzing the different foundations (direct foundation + pile foundation) with the conservative pile foundation and mat foundation. As a result, when the different foundation is applied, the overall settlement amount increased than the conservative pile foundation. However, the difference was very minute and it has been confirmed to be no issue as a result of assessment of stability of the differential settlement of structures through critical angle displacement.