• 제목/요약/키워드: core factor

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초고층건축물의 유형화와 부지 내 배치계획요소 계획현황에 관한 연구 (A Study on the Typological Classification of Super-tall Building and Present State of Masterplan Planning Factor in the Site)

  • 양기인;방기진;제해성
    • KIEAE Journal
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    • 제10권5호
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    • pp.71-76
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    • 2010
  • Recently, the construction and plan of super-tall building is attention link of new town development or urban core regeneration. Super-tall Buildings have many advantages and a lot of affects in urban contexts. Also, construction of super-tall building is will be able to social problem like urban core's decline, loss of openspace, incompatible urban scape, traffic congestion of urban core. But, compares to super-tall buildings affects in urban contexts, there was not extra ordinary study about super-tall building by the urban scale approaches. Therefore, need about study materplan planning of the site which is made to meet super-tall building and urban contexts. There are two main processes in this study. First, to analyze the factors affect to masterplan planning of the super-tall building's site. Through the analyzed factors, classify type of super-tall buildings and identify the type's state. Second, to classify and set the elements of masterplan planning factor in the site. Identify the masterplan planning factor's state by deployment materplan planning factor set the current applied to the constructed super-tall buildings. Through this process, identified the recent trend and providied the basic elements of materplan planning of super-tall building's site.

변압기 코아의 선정 기술 개발 (Choice technique develovement of transformer core)

  • 이오걸;김수용;박두한
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 C
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    • pp.1604-1606
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    • 2003
  • In this paper, investigated the core of transformer of high power factor and high effectiveness about design and choice technology. Transformer that use existent general core and material is high no-load loss power. Presented core choice method that can reduce loss. Could do to reduce loss according to choice technology of use material more than about 10 (%). Presented classification and check list by Core's type.

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Hybrid of the fuzzy logic controller with the harmony search algorithm to PWR in-core fuel management optimization

  • Mahmoudi, Sayyed Mostafa;Rad, Milad Mansouri;Ochbelagh, Dariush Rezaei
    • Nuclear Engineering and Technology
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    • 제53권11호
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    • pp.3665-3674
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    • 2021
  • One of the important parts of the in-core fuel management is loading pattern optimization (LPO). The loading pattern optimization as a reasonable design of the in-core fuel management can improve both economic and safe aspects of the nuclear reactor. This work proposes the hybrid of fuzzy logic controller with harmony search algorithm (HS) for loading pattern optimization in a pressurized water reactor. The music improvisation process to find a pleasing harmony is inspiring the harmony search algorithm. In this work, the adjustment of the harmony search algorithm parameters such as the bandwidth and the pitch adjustment rate are increasing performance of the proposed algorithm which is done through a fuzzy logic controller. Hence, membership functions and fuzzy rules are designed to improve the performance of the HS algorithm and achieve optimal results. The objective of the method is finding an optimum core arrangement according to safety and economic aspects such as reduction of power peaking factor (PPF) and increase of effective multiplication factor (Keff). The proposed approach effectiveness has been tried in two cases, Michalewicz's bivariate function problem and NEACRP LWR core. The results show that by using fuzzy harmony search algorithm the value of the fitness function is improved by 15.35%. Finally, with regard to the new solutions proposed in this research it could be used as a trustworthy method for other optimization issues of engineering field.

한국 금융산업에서의 6시그마시행의 성공요인에 관한 실증연구 (An empirical study on the core factors of implementing 6-sigma in Korea Financial Industry)

  • 김영대
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2006년도 추계학술대회
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    • pp.539-544
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    • 2006
  • This study has been attempted to find that factors for successful six-sigma implementation influence non-financial performance & financial performance in korean finance industry. In addition, goal of this study is to find out core factor in korean finance industry. To achieve the aim of this study, a document study and interview and an empirical analysis were performed. The collected questionnaires for the empirical analysis were processed statistically through data cording. Cronbach'a was conducted to get the construct reliability. To identify which factors for successful six-sigma implementation influence performances of six-sigma implementation, factor analysis was conducted to get the construct validity. After factor analysis, multiple regressions were utilized to identify the core factors (or factors for successful six-sigma implementation). The result of the study that has been derived through this process is summarized below. Firstly, by analyzing the effect factors for successful six-sigma implementation has on non-financial performance of finance industry, it shows that Process-integration & standardization variable has influenced. Secondly, by analyzing the effect factors for successful six-sigma implementation has on financial performance of finance industry, it shows that 'Process-integration & standardization' variables and 'Customer & Market mind' variables have influenced. The results of this study show that 'Process-integration & standardization' and 'Customer & Market mind' are core factors to influence non-financial performance & financial performance in korean finance industry

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First Korean case of factor V Leiden mutation in pregnant woman with a history of recurrent pregnancy loss

  • Han, Sung Hee;Seo, Jung Jae;Kim, Eun Seol;Ryu, Jae Song;Hong, Seong Hyeon;Hwang, Seung Yong
    • Journal of Genetic Medicine
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    • 제16권1호
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    • pp.23-26
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    • 2019
  • Thrombophilia refers to inherited or acquired hemostatic disorders that result in a predisposition to blood clot formation. When combined with the hypercoagulable state that is characteristic of pregnancy, there is an increased risk of severe and recurrent pregnancy complications. Activated protein C resistance caused by factor V Leiden (FVL) mutation is known to be the most common cause of inherited thrombophilia in Caucasian population. FVL mutation has been related to pregnancy complications associated with hypercoagulation, e.g. miscarriage, intrauterine fetal demise, placental abruption, and intrauterine growth retardation. Although the FVL mutation is easily detected using molecular DNA techniques, patients who are heterozygous for this disorder often remain asymptomatic until they develop a concurrent prothrombotic condition. Because there are potentially serious effects of FVL mutation for pregnancy, and because effective treatment strategies exist, early detection and treatment of this condition might be considered.

공학계열 학생 핵심역량 진단도구 개발 및 타당화 연구 (Development and Validation of Core Competency Assessment Tools for Engineering Student)

  • 김윤영;윤지영
    • 공학교육연구
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    • 제24권4호
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    • pp.3-20
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    • 2021
  • As we have become more interested in 'competency' that means ability to do something around the world, the competency of the best performers has also been introduced in the university curriculum as a concept of core competency. Research continues on why this competency-based education is needed compared to existing academic-oriented education, how it can be introduced into existing curricula, and how it can be developed and evaluated in detail. This study develops and validates core competency assessment tools that can diagnose core competencies of engineering students. Therefore, this research paper conducted a literature review related to core competencies and also core competency assessment tools of university students. It seeks to explore the implications of core competency assessment tools for engineering students and then lay the foundation for competency-based teaching and learning at engineering colleges. And also it defines the concepts of core competencies and each core competency of engineering students through prior research analysis of competence, core competence, and core competence of university students. The primary core competency assessment tool consisted of sub-factors and questions of core competencies. It were modified through the expert validation of the primary one and then it was used as a core competency assessment tools for preliminary investigation. The core competency assessment tools for engineering students are consisted of 6 competencies, 22 sub-factors, and 91 questions. There are core competencies as follows: engineering basic competencies, major engineering competencies, self-management competencies, communication competencies, interpersonal competencies, global competencies. The preliminary survey was conducted on 426 engineering students attending the Engineering Education FESTA 2019. The preliminary findings were derived by conducting exploratory factor analysis, confirmatory factor analysis, question characteristics analysis, and reliability analysis for validation. The core competency assessment tools developed through this study can be used to verify the effectiveness of the curriculum and programs for students at engineering colleges. In addition, the developed core competencies, sub-factors, and questions can be utilized in a series of courses that design, conduct, and evaluate engineering curricula and programs as competency-based curriculum. The significance of this study is to lay the groundwork for providing competency-based education engineering students to develop core competencies.

SENSITIVITY ANALYSES OF THE USE OF DIFFERENT NEUTRON ABSORBERS ON THE MAIN SAFETY CORE PARAMETERS IN MTR TYPE RESEARCH REACTOR

  • Kamyab, Raheleh
    • Nuclear Engineering and Technology
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    • 제46권4호
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    • pp.513-520
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    • 2014
  • In this paper, three types of operational and industrial absorbers used at research reactors, including Ag-In-Cd alloy, $B_4C$, and Hf are selected for sensitivity analyses. Their integral effects on the main neutronic core parameters important to safety issues are investigated. These parameters are core excess reactivity, shutdown margin, total reactivity worth of control rods, thermal neutron flux, power density distribution, and Power Peaking Factor (PPF). The IAEA 10 MW benchmark core is selected as the case study to verify calculations. A two-dimensional, three-group diffusion model is selected for core calculations. The well-known WIMS-D4 and CITATION reactor codes are used to carry out these calculations. It is found that the largest shutdown margin is gained using the $B_4C$; also the lowest PPF is gained using the Ag-In-Cd alloy. The maximum point power densities belong to the inside fuel regions surrounding the central flux trap (irradiation position), surrounded by control fuel elements, and the peripheral fuel elements beside the graphite reflectors. The greatest and least fluctuation of the point power densities are gained by using $B_4C$ and Ag-In-Cd alloy, respectively.

Rotor에 대한 Cu-bar 압입시 응력분포에 대한 연구 (A Study on the Stress Distribution in Rotor Core inserted with Cu bar)

  • 박상철;김현수
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2003년도 추계학술대회논문집
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    • pp.251-254
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    • 2003
  • In this study, main works are focused on investigating the stress distribution at the interface between a rotor core and Cu bar when a punch is applied into the body of Cu bar. A parametric study with dimensional changes of core slot was performed numerically to identify what factors are dominant in producing high contact forces in the interface. As analysis results, it was found that core slot length was a dominant factor in increasing contact force at the interface between a rotor core and Cu bar.

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Damping and vibration response of viscoelastic smart sandwich plate reinforced with non-uniform Graphene platelet with magnetorheological fluid core

  • Eyvazian, Arameh;Hamouda, Abdel Magid;Tarlochan, Faris;Mohsenizadeh, Saeid;Dastjerdi, Ali Ahmadi
    • Steel and Composite Structures
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    • 제33권6호
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    • pp.891-906
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    • 2019
  • This study considers the instability behavior of sandwich plates considering magnetorheological (MR) fluid core and piezoelectric reinforced facesheets. As facesheets at the top and bottom of structure have piezoelectric properties they are subjected to 3D electric field therefore they can be used as actuator and sensor, respectively and in order to control the vibration responses and loss factor of the structure a proportional-derivative (PD) controller is applied. Furthermore, Halpin-Tsai model is used to determine the material properties of facesheets which are reinforced by graphene platelets (GPLs). Moreover, because the core has magnetic property, it is exposed to magnetic field. In addition, Kelvin-Voigt theory is applied to calculate the structural damping of the piezoelectric layers. In order to consider environmental forces applied to structure, the visco-Pasternak model is assumed. In order to consider the mechanical behavior of structure, sinusoidal shear deformation theory (SSDT) is assumed and Hamilton's principle according to piezoelasticity theory is employed to calculate motion equations and these equations are solved based on differential cubature method (DCM) to obtain the vibration and modal loss factor of the structure subsequently. The effect of different factors such as GPLs distribution, dimensions of structure, electro-magnetic field, damping of structure, viscoelastic environment and boundary conditions of the structure on the vibration and loss factor of the system are considered. In order to indicate the accuracy of the obtained results, the results are validated with other published work. It is concluded from results that exposing magnetic field to the MR fluid core has positive effect on the behavior of the system.

미 군사규격을 적용한 권취 코어 자동공급장치의 진동해석 (Vibration Analysis of Film Winding Core Automatic Supply System Using US Military Standards)

  • 고정일;박수현;허장욱
    • 한국기계가공학회지
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    • 제21권4호
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    • pp.91-99
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    • 2022
  • By applying METHOD 514.8 of the US military standard MIL-STD-810H, vibration analysis of the winding core automatic feeding device was performed during vehicle transportation. The contact point between the LM guide and main support frame was weak in the vertical axis, transverse axis, and longitudinal axis during the transportation of the automatic winding core feeder vehicle, and the maximum equivalent stress was 236.31 MPa in the longitudinal axis. When random vibration was applied, the safety margin in the longitudinal direction was 0.26, indicating low safety. The safety margin was changed by increasing the damage factor to 0.1. Finally, the safety margin was improved to 3.48 to secure safety. Resonance occurred with a Q factor of 9.34 in the harmonic response to which the RMS value of the ASD data was input, and the vertical axis safety margin was derived as 0.16. When the damping factor was 0.15, the Q factor was 3.37, and resonance was avoided with a safety margin of 6.62.