• Title/Summary/Keyword: Inconsistencies

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DEVELOPMENT OF AN INTEGRATED RISK ASSESSMENT FRAMEWORK FOR INTERNAL/EXTERNAL EVENTS AND ALL POWER MODES

  • Yang, Joon-Eon
    • Nuclear Engineering and Technology
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    • v.44 no.5
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    • pp.459-470
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    • 2012
  • From the PSA point of view, the Fukushima accident of Japan in 2011 reveals some issues to be re-considered and/or improved in the PSA such as the limited scope of the PSA, site risk, etc. KAERI (Korea Atomic Energy Research Institute) has performed researches on the development of an integrated risk assessment framework related to some issues arisen after the Fukushima accident. This framework can cover the internal PSA model and external PSA models (fire, flooding, and seismic PSA models) in the full power and the low power-shutdown modes. This framework also integrates level 1, 2 and 3 PSA to quantify the risk of nuclear facilities more efficiently and consistently. We expect that this framework will be helpful to resolve the issue regarding the limited scope of PSA and to reduce some inconsistencies that might exist between (1) the internal and external PSA, and (2) full power mode PSA and low power-shutdown PSA models. In addition, KAERI is starting researches related to the extreme external events, the risk assessment of spent fuel pool, and the site risk. These emerging issues will be incorporated into the integrated risk assessment framework. In this paper the integrated risk assessment framework and the research activities on the emerging issues are outlined.

An Algorithm for Automatic Generation of Dimension and Tolerance Charts (치수/공차표의 자동생성 알고리듬)

  • Jung, Jong-In;Kim, Kwang-Soo;Choi, Hoo-Gon
    • Journal of Korean Institute of Industrial Engineers
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    • v.29 no.1
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    • pp.21-31
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    • 2003
  • Determination of operational dimensions and tolerances is complex if there exist inconsistencies between operational and design specifications. Dimension and tolerance charts (D&T charts) have been used to establish the relationships among operational dimensions in complex machining. This chart proves that individual operations can be harmonized when they are interconnected. However, it is hard to generate the chart manually. Because operational dimensions and tolerances must meet the design specifications, the dimensions and tolerances of interconnected operations have to be verified serially for economical operations. In this paper, the chart is automatically generated from the interconnected operations. More importantly, all operational dimensions and tolerances displayed in the chart have been verified by using LP to meet the design specifications. Finally, the chart is converted to an operational routing sheet that contains a detailed process plan along with cutting speed, feed rate, and operational references based on material hardness, surface finish, and tool nose radius.

Restructuring a Feed-forward Neural Network Using Hidden Knowledge Analysis (학습된 지식의 분석을 통한 신경망 재구성 방법)

  • Kim, Hyeon-Cheol
    • Journal of KIISE:Software and Applications
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    • v.29 no.5
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    • pp.289-294
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    • 2002
  • It is known that restructuring feed-forward neural network affects generalization capability and efficiency of the network. In this paper, we introduce a new approach to restructure a neural network using abstraction of the hidden knowledge that the network has teamed. This method involves extracting local rules from non-input nodes and aggregation of the rules into global rule base. The extracted local rules are used for pruning unnecessary connections of local nodes and the aggregation eliminates any possible redundancies arid inconsistencies among local rule-based structures. Final network is generated by the global rule-based structure. Complexity of the final network is much reduced, compared to a fully-connected neural network and generalization capability is improved. Empirical results are also shown.

Factors of parenting behavior associated with family support of college freshman (일 여대신입생이 인지하는 부모 양육행동이 가족지지에 미치는 영향)

  • Yoon, Hee-Sang;Kim, Gyung-Hee
    • The Journal of Korean Society for School & Community Health Education
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    • v.12 no.2
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    • pp.1-12
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    • 2011
  • Objectives: This study was carried out to investigate parent behavioral factors associated with perceived family support of college fresh-woman, in part to find the way of successful college life. Methods: Self-administered questionnaires were given to 256 freshman enrolled in college, between 2weeks may and June 2009. The questionnaire items general characteristics included religion, college entry form(high school graduation/other college expierence), allowance, college life satisfaction, self rated health and family support, parenting behaviors. Parenting behavior consists of affection, reasonable explanation, abuse, excessive interference, supervision, negligence, inconsistencies. The dependent variable is perceived family support, independent variable mother and father behaviors that consisted of above 8 spheres. Results: For the statistical analysis, the t-test was used for the family support and parenting behaviors according to the general characteristics. The influence elicited by the instrument of parenting behavior was determined using multiple regression under the control of general characteristics. The influencing factors are mothers's affection and father's supervision, neglection and affection. Conclusion: Based on the study results, it is important father's behavior to their children especially they are regarded as father's neglect is not support them. We suggest that, for father's behavior strategies should be developed to perceive their family support.

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Gene-Diet Interaction on Cancer Risk in Epidemiological Studies

  • Lee, Sang-Ah
    • Journal of Preventive Medicine and Public Health
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    • v.42 no.6
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    • pp.360-370
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    • 2009
  • Genetic factors clearly play a role in carcinogenesis, but migrant studies provide unequivocal evidence that environmental factors are critical in defining cancer risk. Therefore, one may expect that the lower availability of substrate for biochemical reactions leads to more genetic changes in enzyme function; for example, most studies have indicated the variant MTHFR genotype 677TT is related to biomarkers, such as homocysteine concentrations or global DNA methylation particularly in a low folate diet. The modification of a phenotype related to a genotype, particularly by dietary habits, could support the notion that some of inconsistencies in findings from molecular epidemiologic studies could be due to differences in the populations studied and unaccounted underlying characteristics mediating the relationship between genetic polymorphisms and the actual phenotypes. Given the evidence that diet can modify cancer risk, gene-diet interactions in cancer etiology would be anticipated. However, much of the evidence in this area comes from observational epidemiology, which limits the causal inference. Thus, the investigation of these interactions is essential to gain a full understanding of the impact of genetic variation on health outcomes. This report reviews current approaches to gene-diet interactions in epidemiological studies. Characteristics of gene and dietary factors are divided into four categories: one carbon metabolism-related gene polymorphisms and dietary factors including folate, vitamin B group and methionines; oxidative stress-related gene polymorphisms and antioxidant nutrients including vegetable and fruit intake; carcinogen-metabolizing gene polymorphisms and meat intake including heterocyclic amins and polycyclic aromatic hydrocarbon; and other gene-diet interactive effect on cancer.

Issues in the Design of Molecular and Genetic Epidemiologic Studies

  • Fowke, Jay H.
    • Journal of Preventive Medicine and Public Health
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    • v.42 no.6
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    • pp.343-348
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    • 2009
  • The final decision of study design in molecular and genetic epidemiology is usually a compromise between the research study aims and a number of logistical and ethical barriers that may limit the feasibility of the study or the interpretation of results. Although biomarker measurements may improve exposure or disease assessments, it is necessary to address the possibility that biomarker measurement inserts additional sources of misclassification and confounding that may lead to inconsistencies across the research literature. Studies targeting multi-causal diseases and investigating gene-environment interactions must not only meet the needs of a traditional epidemiologic study but also the needs of the biomarker investigation. This paper is intended to highlight the major issues that need to be considered when developing an epidemiologic study utilizing biomarkers. These issues covers from molecular and genetic epidemiology (MGE) study designs including cross-sectional, cohort, case-control, clinical trials, nested case-control, and case-only studies to matching the study design to the MGE research goals. This review summarizes logistical barriers and the most common epidemiological study designs most relevant to MGE and describes the strengths and limitations of each approach in the context of common MGE research aims to meet specific MEG objectives.

Shared Data Decomposition Model for Improving Concurrency in Distributed Object-oriented Software Development Environments (분산 객체 지향 소프트웨어 개발 환경에서 동시성 향상을 위한 공유 데이타 분할 모델)

  • Kim, Tae-Hoon;Shin, Yeong-Gil
    • Journal of KIISE:Software and Applications
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    • v.27 no.8
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    • pp.795-803
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    • 2000
  • This paper presents a shared data decomposition model for improving concurrency in multi-user, distributed software developments. In our model, the target software system is decomposed into the independent components based on project roles to be distributed over clients. The distributed components are decomposed into view objects and core objects to replicate only view objects in a distributed collaboration session. The core objects are kept in only one client and the locking is used to prevent inconsistencies. The grain size of a lock is a role instead of a class which is commonly used as the locking granularity in the existing systems. The experimental result shows that our model reduces response time by 12${\sim}$18% and gives good scalability.

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The Stopping Power and Cross-section Measurement of $\alpha$-particle in Ar, He and $N_2$ gases (Ar, He 및 $N_2$ 가스의 $\alpha$-입자 저지능과 저지 단면적 측정)

  • Lee, Jung-Hoon;Hwang, Jae-Kwang;Hwang, Han-Yull;Chung, Won-Mo;Joo, Koan-Sik
    • Journal of Radiation Protection and Research
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    • v.13 no.2
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    • pp.1-8
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    • 1988
  • The energy losses of ${\alpha}$-particle with 3 to 5.4 MeV energy were measured as a function of gas absorber thickness and ${\alpha}$-particle energy in three light gaseous media; He, Ar, and $N_2$. The stopping powers and stopping cross-sections were determined by analyzing these data. For Ar gas, the experimental values are very well consistent with the corresponding values of Srivastava's stopping-power theory with the condition of the completely and partially stripped ion. For $N_2$ and He gases, these experimental values express the inconsistencies of about $13{\sim}36%$ and $27{\sim}28%$, respectively.

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The Improvement of Wetland Conservation Plan for Upo Wetland Protected Area (우포늪 습지보호지역 보전계획 개선방안)

  • Kim, Su-Ryeon;Song, Won-Kyong
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.22 no.4
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    • pp.65-80
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    • 2019
  • The Wetland Conservation Plan is used as a tool to set the management direction of wetland protected areas, and which is establishing a plan for the conservation, wise-use, and management based on wetland's condition. This study was conducted to establish a conservation plan considering the functions and management conditions of Upo wetland protected area. To this end, there are analyzed the current issues, plans and implementation status of Upo Wetland Conservation Plans in the past. The management elements to be considered in establishing the Wetland Conservation Plan were selected through prior research analysis and the priority of those elements was identified through the AHP. As a result, it was found that lack of considering the changes and performance evaluation of the existing plans in wetlands, conducting short-term projects related to maintenance original function of wetland, different management methods for wetland protected areas and other adjacent areas, lack of understanding and cooperation by stakeholders, inconsistencies in timing of the Conservation Plan and survey of wetland protected areas. In order to improve the problem, it needs to include the performance evaluation stage of establishing the conservation plan, strengthen cooperation of stakeholders and expertise, continuing of projects for wetlands' maintenance, priority of the project considering the management side, and to adjust the timing of plans to improve data availability.

Analysis, Design and Implementation of Flexible Interlaced Converter for Lithium Battery Active Balancing in Electric Vehicles

  • Dai, Shuailong;Wang, Jiayu;Li, Teng;Shan, Zhifei;Wei, Yewen
    • Journal of Power Electronics
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    • v.19 no.4
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    • pp.858-868
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    • 2019
  • With the widespread use of modern clean energy, lithium-ion batteries have become essential as a more reliable energy storage component in the energy Internet. However, due to the difference in monomers, some of the battery over-charge or over-discharge in battery packs restrict their use. Therefore, a novel multiphase interleaved converter for reducing the inconsistencies of the individual cells in a battery pack is proposed in this paper. Based on the multiphase converter branches connected to each lithium battery, this circuit realizes energy transferred from any cell(s) to any other cell(s) complementarily. This flexible interlaced converter is composed of an improved bi-directional Buck-Boost circuit that is presented with its own available control method. A simulation model based on the PNGV model of fundamental equalization is built with four cells in PSIM. Simulation and experimental results demonstrate that converter and its control achieve simple and fast equalization. Furthermore, a comparison of traditional methods and the HNFABC equalization is provided to show the performance of the converter and the control of lithium-based battery stacks.