• Title/Summary/Keyword: analytic method

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A Nonlinear Analytic Function Expansion Nodal Method for Transient Calculations

  • Joo, Han-Gyu;Park, Sang-Yoon;Cho, Byung-Oh;Zee, Sung-Quun
    • Proceedings of the Korean Nuclear Society Conference
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    • 1998.05a
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    • pp.79-86
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    • 1998
  • The nonlinear analytic function expansion nodal (AFEN) method is applied to the solution of the time-dependent neutron diffusion equation. Since the AFEN method requires both the particular solution and the homogeneous solution to the transient fixed source problem, the derivation solution method is focused on finding the particular solution efficiently. To avoid complicated particular solutions, the source distribution is approximated by quadratic polynomials and the transient source is constructed such that the error due to the quadratic approximation is minimized. In addition, this paper presents a new two-node solution scheme that is derived by imposing the constraint of current continuity at the interface corner points. The method is verified through a series of applications to the NEACRP PWR rod ejection benchmark problem.

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Calculation of Capacitance Using Surface-Contacted Element and Application (표면접촉요소에 의한 정전용량계산 및 응용)

  • 박필용;현정수;최승길;심재학;강형부
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.05a
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    • pp.399-402
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    • 1999
  • In this paper, a new method for calculating capacitance in arbitrarily shape structure is Presented. This new approach based on divergence theorem of Gauss\`s law is acheive by Surface-Contacted Element(SCE) for Gaussian surface. To evaluate accurate capacitance value in nonuniform electric field. in two dimensional analysis the interpolation using the elements which contact one nod (PE: Point-Element) or two nod (FE: Face-Element) is employed. Because the elements contacted with surface are very small compared with total elements in analytic model, SCE method has shorter computing time to calculate capacitance. This proposed method is verified by comparing the simulated results with value obtained by analytic method.

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Analysis of Ultrasonic Linear Motor Using the Finite Element Method and Equivalent Circuit

  • Park, Jong-Seok;Joo, Hyun-Woo;Lee, Chang-Hwan;Jung, Hyun-Kyo
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • v.3B no.4
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    • pp.159-164
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    • 2003
  • In this paper, a three-dimensional finite element method and construction of equivalent-circuit for a linear ultrasonic motor are presented. The validity of three-dimensional finite element routine in this paper is experimentally confirmed by analyzing impedance of a piezoelectric transducer. Using this confirmed finite element routine, impedance and vibration mode of a linear ultrasonic motor are calculated. Elliptical motion of contact point between vibrator and rail of the linear ultrasonic motor is shown for determination of contact points. By using the finite element method and analytic equations, characteristics of the linear ultrasonic motor, such as thrust force, speed, losses, powers and efficiency, are calculated. The results are confirmed by experiment. Finally, equivalent circuit parameters of the linear ultrasonic motor are obtained using the three-dimensional finite element method and analytic equations.

Reliability Evaluation of Power Distribution Systems Considering the Momentary Interruptions-Application of Monte Carlo Method (순간정전을 고려한 배전계통에서의 신뢰도 평가-몬테카를로 방식의 적용)

  • Sang-Yun Yun;Jae-Chul Kim
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.52 no.1
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    • pp.9-16
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    • 2003
  • In this paper, we propose a reliability evaluation method considering the momentary interruptions of power distribution systems. The results of research are concentrated on two parts. One is the analytic and probabilistic reliability evaluation of power distribution system considering the momentary interruptions and the other is the reliability cost evaluation that unifies the cost of sustained and momentary interruptions. This proposed reliability cost evaluation methodology is also divided into the analytic and probabilistic approach and the time sequential Monte Carlo method is used for the probabilistic method. The proposed methods are tested using the modified RBTS (Roy Billinton Test System) form and historical reliability data of KEPCO (Korea Electric Power Corporation) system. Through the case studies, it is verified that the proposed reliability evaluation and its cost/worth assessment methodologies can be applied to the actual reliability studies.

A Producing Process for Korean Nursing Knowledge and Discourse on Analytic Prospects (한국 간호지식체의 생산과정과 담론분석적 전망)

  • 권봉숙;박형숙
    • Journal of Korean Academy of Nursing
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    • v.27 no.1
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    • pp.61-70
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    • 1997
  • The purpose of this study was to identify the producing process for Korean nursing knowledge as applied by Foucault's discourse analytic method. By Foucault's discourse analytic method, the problem is not what is knowledge but what sort of knowledge is made up through specific level of practice. A Korean body of nursing knowledge has been discussed since 1980. At the end of 19th century, missionaries transplanted western nursing knowledge and method to Korea. Western nursing knowledge and methods have been developed continuously with both merits and demerits to Korean society. Recently our world has be come a global community via advances in transportation and correspondence. Although each person is different in skin color and shape. there is a clear line between Oriental people and Western people. Nursing science is only one in our world. but western humanistic nursing practice based on western worldview and human life has limits. It is natural that the Koreans as Oriental people have a systemic nursing science to reveal the specific experiential and concrete body of nursing knowledge rooted in the Korean worldview and human life. Nursing science is to understand human beings, to promote health. to prevent illness. to restore health. to alleviate suffering and to search for principles needed throughout all of human life. In Korea, now is the quickening period to shape a Korean body of nursing knowledge because of a shortage of nursing language in matters of intellectual recognition, and unfamiliar practical nursing field where there is no familiarity in the system of nursing research methodology. In reviewing articles from the Journal of the Nurses' Academic Society on Korean body of nursing knowledge, it was found that there are two common features. The first, human body and mind are inseperable that is one unit in this world and health is keeping a harmonious relationship between human body and mind. The second, Korean nursing practice is based on human nature and family ties. Accordingly discourse analysis has a good future prospect to produce a Korean body of nursing knowledge for analytic research on body and mind monism and family centered care based on human nature and family ties.

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Exploring Military Survey Study Based on the Characteristics of Rank Structure (계급구조특성을 고려한 군(軍) 조사연구의 탐색)

  • Ki, No-Kyoung
    • Survey Research
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    • v.10 no.2
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    • pp.115-136
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    • 2009
  • This paper examines the past tendencies of survey study on military organizations and explores the directions and alternatives of research study based on one of the main military characteristics of rank structure. Military survey study has limitations in confirming the credibility of the research results and in supporting implications on the diverse subjects due to the constraining research environment in the military. This study deduced survey designs and analytic methods fit for the research objective upon multidimensionally grasping the characteristics of the hierarchical rank structure which influences the survey process aid its result crucially. It proposes that the future direction of military survey study is to elaborate research method and multidimensionalize analytic methodology. More specifically. this paper insists that it is necessary to design method and process of the survey delicately and to develop analytic methodology which can analyze diverse factors.

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Optimal Decision of River Width Work Using Analytic Hierarchy Process-Case Study of IP-Chon (AHP기법을 이용한 최적 계획하폭 선정-입천에의 적용 사례연구)

  • Lee, Jae-Mun;Lee, Sang-Il
    • Journal of Korea Water Resources Association
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    • v.40 no.12
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    • pp.931-941
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    • 2007
  • Traditionally, the decision of river width has aimed majorly at flood control and good river conveyance. And the river width has been decided by practitioner#s subjective and empirical opinion. Recently, however, there is a need for more objective and thus quantitative decision method for decision of river width considering not only economical aspect but also social or environmental aspect. This study adopts the analytic hierarchy process (AHP) to improve the objectiveness in the decision of river width. Criteria and a standardized process are presented for field application. Using the proposed method, one can prioritize various river width and make the optimal decision. We believe that the method can serve as a useful tool for river engineers in practice.

Extension of Source Projection Analytic Nodal $S_N$ Method for Analysis of Hexagonal Assembly Cores

  • Kim, Tae-Hyeong;Cho, Nam-Zin
    • Nuclear Engineering and Technology
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    • v.28 no.5
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    • pp.488-499
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    • 1996
  • We have extended the source projection analytic nodal discrete ordinates method (SPANDOM) for more flexible applicability in analysis of hexagonal assembly cores. The method (SPANDOM-FH) does not invoke transverse integration but instead solves the discrete ordinates equation analytically after the source term is projected and represented in hybrid form of high-order polynomials and exponential functions. SPANDOM-FH which treats a hexagonal node as one node is applied to two fast reactor benchmark problems and compared with TWOHEX. The results of comparison indicate that the present method SPANDOM-FH predicts accurately $k_eff$ and flux distributions in hexagonal assembly cores. In addition, SPANDOM-FH gives the continuous two dimensional intranodal scalar flux distributions in a hexagonal node. The reentering models between TWOHEX and SPANDOM were also compared and it was confirmed that SPANDOM's model is more realistic. Through the results of benchmark problems, we conclude that SPANDOM-FH has the sufficient accuracy for the nuclear design of fast breeder reactor (FBR) cores with hexagonal assemblies.

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Collection Efficiency of Electrostatic Precipitator using Moment Method (모멘트 방법을 이용한 전기집진기의 집진 효율)

  • 정창훈;이규원
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.5
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    • pp.345-353
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    • 2002
  • A study of polydispersed aerosol dynamics by Electrostatic Precipitator (ESP) was carried out. The log-normal particle size distribution was assumed and moment method was considered. In order to apply moment method in Deutsch-Anderson equation, Cunningham slip correction factor and Cochet's charge equation were simplified for certain range of particle size. The three parameters, which explain the particle size distribution, such as total number concentration, geometric mean diameter, and geometric standard deviation were considered to derive the analytic solution. The obtained solution was compared with available numerical results (Bai et al., 1995). The comparison of the numerical and analytic results showed a good agreement.

A Study on the Reliability Evaluation for Inchon International Airport Distribution System (인천국제공항 배전계통의 신뢰도 평가에 관한 연구)

  • Kim, Yong-Ha;Lee, Buhm;Choi, Sang-Kyu;Chung, Young-Sik;Moon, Jeong-Ho
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.10
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    • pp.1198-1205
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    • 1999
  • This study is focused on the reliability evaluation for distribution system based on deterministic evaluation technique. Average failure rates, average outage time, and average annual outage time of electrical parts and load points are calculated through network reduction method and failure mode & effective analysis method. And reliability indices of distribution system are calculated. Finally, by employing analytic hierarchy process method, unique index which evaluates and improves the distribution system is calculated. As a result, finding weak points and expansion schedule of the system is possible. The usefulness of this method is verified by applying it to the Inchon International Airport.

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