• 제목/요약/키워드: second-order expansion

검색결과 323건 처리시간 0.03초

구직자 코드확장 규칙을 적용한 레이블 친숙성 연구 (A Study of Label Intimacy Applied by Applicant's Code-Expansion Rule)

  • 양승해;정은희;이병관
    • 한국정보전자통신기술학회논문지
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    • 제3권1호
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    • pp.57-62
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    • 2010
  • 본 논문에서는 취업정보를 원활하게 접할 수 있는 환경을 제공하기 위한 구직 구인 정보를 구축하기 위하여 2가지를 제시하였다. 첫째, 취업사이트를 구축하기 위해 실 사례를 대상으로 데이터베이스 코드 확장 기준, 카테고리화 기준, 그리고 ERD (Entity Relation Diagram)를 설계하였다. 둘째, 친숙성이 강한 레이블 규칙을 위한 소수 레이블링 기준을 정의하였다. 따라서, 데이터베이스를 설계 및 구축하는데 있어 일정한 규칙을 체계적으로 적용함으로써 데이터베이스 구축 운영시 일관성과 효율성을 높이고 응용프로그램 개발 및 운영의 편의를 제공할 수 있으며 제안한 코드 확장 규칙 정의는 국내외 구인 구직 정보제공 기관에 표준화가 가능하다.

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부가성 잡음이 존재하는 모노펄스 시스템 성능의 3차 테일러 전개 기반 해석적 분석 (Performance Analysis of Monopulse System Based on Third-Order Taylor Expansion in Additive Noise)

  • 함형우;김건영;이준호
    • 융합정보논문지
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    • 제11권12호
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    • pp.14-21
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    • 2021
  • 본 논문은 가산성 잡음이 존재할 경우 모노펄스 알고리즘의 성능분석을 해석적으로 분석한 연구이다. 이전 연구에서는 1차 테일러 급수 전개와 2차 테일러 급수 전개를 통한 진폭비교 모노펄스 알고리즘의 해석적 성능 분석을 진행했다. 본 연구에는 3차 테일러 전개기반 해석적 분석법을 적용하여 1차 및 2차 테일러 근사기반의 해석적 분석보다 실제 모노펄스 알고리즘의 성능 분석 결과에 다가가는 것을 보인다. 성능분석은 평균제곱오차(Mean Squre Error)을 통해 분석되며 몬테카를로(Monte-Calro) 방법을 통한 시뮬레이션 MSE와 3차 테일러 근사기반 해석적 MSE를 서로 비교한다. 3차 테일러 근사기반 해석적 MSE를 적용하였을 경우, 이전 연구에서 제안된 2차 테일러 근사기반의 해석적 MSE의 오차를 89.5% 감소시킨다. 또한 몬테카를로 기반 MSE보다 모든 경우에서 빠른 결과를 보인다. 해당 연구를 통해 잡음 재밍이 적용된 환경에서 모노펄스 레이더의 추정 각도 능력을 명시적으로 분석이 가능하다.

효율적인 전압안정도 한계점 계산에 관한 연구 (Effective Calculation Method Finding the Limit of Voltage-Stability)

  • 송길영;김세영;최상규
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1991년도 추계학술대회 논문집 학회본부
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    • pp.35-38
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    • 1991
  • Recent, problems on the voltage-instability have been paid attention in power system and methods to find the limit of voltage-stability, concerned with these problems, were developed. However, these methods are short of precision on the limit of voltage-instability. Here, using the second-order load flow, constraint equation(d Pi/d Vi=0) and its patial differentiations are precisely formulated. Also, since the taylor series expansion of power flow equations terminates at the second-order terms, partial differentiations of constraint equation, that is Hessian, are constant. Then, Hessian matrix are calculated once during iteration process.

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Optimal designs for small Poisson regression experiments using second-order asymptotic

  • Mansour, S. Mehr;Niaparast, M.
    • Communications for Statistical Applications and Methods
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    • 제26권6호
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    • pp.527-538
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    • 2019
  • This paper considers the issue of obtaining the optimal design in Poisson regression model when the sample size is small. Poisson regression model is widely used for the analysis of count data. Asymptotic theory provides the basis for making inference on the parameters in this model. However, for small size experiments, asymptotic approximations, such as unbiasedness, may not be valid. Therefore, first, we employ the second order expansion of the bias of the maximum likelihood estimator (MLE) and derive the mean square error (MSE) of MLE to measure the quality of an estimator. We then define DM-optimality criterion, which is based on a function of the MSE. This criterion is applied to obtain locally optimal designs for small size experiments. The effect of sample size on the obtained designs are shown. We also obtain locally DM-optimal designs for some special cases of the model.

유전자 알고리즘을 이용한 HFC의 최적설계 (The Optimal Design of HFC by means of GAs)

  • 이대근;오성권;장성환
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.369-369
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    • 2000
  • Control system by means of fuzzy theory has demonstrated its robustness in applying to the high-order and nonlinear dynamic system in that it can utilizes the human expert knowledges in system design. In this paper, first, the design methodology of HFC combined PID controller with fuzzy controller by membership function of weighting coefficient is proposed. Second, Second, an auto-tuning algorithms utilizing the simplified reasoning method and genetic algorithms is presented to improve the performance of hybrid fuzzy controller. Especially, in order to obtain the optimal scaling factors and PID parameters of HFC using GA based on advanced initial individual, three kinds of estimation modes such as basic, contraction, and expansion mode are effectively utilized. The proposed HFC is evaluated and discussed in ITAE, overshoot and rising time to show applicability and superiority with simulation results.

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내수면 어로어업의 동향과 재편과제에 관한 연구 (A Study on the Reorganization of the Management System in Korean Inland Fisheries)

  • 김대영;이정삼
    • 수산해양교육연구
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    • 제19권1호
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    • pp.34-52
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    • 2007
  • This study analyses the management and utilization of Korean inland fisheries and suggests directions for reorganizing the fisheries in order to achieve qualitative growth. Inland fisheries developing into a unique fishery according to various aquatic systems in different areas have played various roles such as the efficient use of aquatic resources, development of local areas and economy vitalization in under-developed local areas. However, recently Korean inland fisheries are facing a lot of difficulties due to the circumstantial changes surrounding the fisheries. Even though it is difficult to expect the external expansion of the Korean inland fisheries, we could expect qualitative internal growth by achieving the sustainable management and aquatic ecosystem health. Therefore, this study suggests the followings in order to achieve the qualitative growth of the Korean inland fisheries : first, construction of integrated management system according the aquatic systems ; second, organization of fishermen's interest groups such as cooperatives or associations in order to increase the competitive advantage and spread voluntary fisheries management ; third, boosting stock enhancement through systematic stock assessment and stocking ; fourth, expansion and activation of administrative system and research organizations.

AHP 기법을 이용한 우리나라 수산업관측사업의 추진방향에 관한 연구 (A Study on Development Strategies of the Korean Fisheries Outlook Project based on AHP)

  • 남종오;노승국
    • 수산경영론집
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    • 제41권1호
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    • pp.25-52
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    • 2010
  • The purpose of this paper is to suggest major strategies and necessary new projects for the medium- and long-term development of the Korean Fisheries Outlook Project. To suggest the Korean Fisheries Outlook Center with the above purpose, this paper employs Analytic Hierarchy Process analysis based on surveys obtained by special groups related with the KFOP. The survey is broadly composed of two goals; the medium- and long-term development directions and setting up of new furtherance projects. Each goal has upper and lower strategies respectively. The first goal, the medium- and long-term development directions, has four factors as upper strategies. The upper strategies are composed of accuracy, efficiency, timeliness, and political effectiveness of the fisheries outlook information. In addition, each upper strategy has three lower strategies respectively. For example, accuracy of the fisheries outlook information includes strength of data collection function, strength of satellite photography function, and strength of data analysis function. The second goal, setting up of new furtherance projects, has three factors as upper strategies. The upper strategies consist of accuracy promotion of outlook information using high-technique, field expansion of outlook species, and strength of analyzing function on oversea fisheries information. Each upper strategy has three lower strategies respectively. For instant, accuracy promotion of outlook information using high-technique has strength of information analysis function covered from production to consumption, strength of satellite information function, and structure of forecasting model on demand and supply by outlook species. The above upper and lower strategies were analytically drawn out through insightful interviews with special groups such as officials of the government, presidents of the producer and distributor groups, and researchers of the Korea Maritime Institute and other research institutes. As a result of AHP analysis, first, priorities of upper strategies with the medium- and long-term development directions are analyzed as accuracy, timeliness, political effectiveness, and efficiency in order. Also, priorities of all lower strategies reflecting priorities of upper strategies are examined as includes strength of data collection function on the fisheries outlook information, delivery of rapid information on outlook products for all people interested, strength of data analysis function on fisheries outlook information, strength of consumption outlook function on fish products, and strength of early warning system for domestic fish products in order. Second, priorities of upper strategies with the setting up of new furtherance projects are analyzed as accuracy promotion of outlook information using high-technique, field expansion of outlook species, and strength of analysis function on oversea fisheries information in order. In addition, priorities of all lower strategies reflecting priorities of upper strategies are examined as building up of forecasting model on demand and supply by outlook species, strength of information analysis function covering all steps from production to consumption, expansion of consumption outlook for consumers, strength of movement analysis function of oversea farming industry, and outlook expansion of farming species.

추적자를 이용한 오염물질 거동분석

  • 김기철;이종석;이재철;김윤호;연기흠
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2008년도 춘계 종합학술대회 논문집
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    • pp.289-293
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    • 2008
  • 본 연구에서는 하천에 유입된 오염물질의 거동 및 확산특성을 파악하기 위하여 실제 하천에서 RI(Radioactive Isotope) 추적자를 이용하여 오염물 확산을 실측하고 그 결과를 수치모형과 비교분석하였다. 연구대상 수로구간은 금강 상류지역의 용담댐 부근 남대천 합류지점으로부터 하류로 약 2km구간에서 실험을 하였으며, 수치모형으로는 RMA-2(Resource Modeling Associates), RMA-4를 사용하였다. RI를 이용한 현장실험은 모델링을 적용한 지역과 동일 지역에서 실험을 실시하였고, 각 구간의 간격은 1km로 정하되 현장 사정에 따라 차이를 조금 두어 RI계측기를 통한 1초간격의 농도 데이터를 계측하였다. 계측결과는 수치모형의 결과와 실제 하천에서의 확산범위 및 확산에 큰 영향을 미치는 확산계수 변화에 따른 농도 분포를 비교 분석하였다. 본 연구를 통해 확산계수가 하천의 오염전파에 미치는 영향과 실측된 농도 데이터를 통해 최초 및 최대농도 도달시간을 파악할 수 있었고, 이것으로 인하여 확산계수를 산정을 할 수 있는 기초자료를 마련하였다.

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하천에서 추적자를 이용한 오염물질 거동분석 (Analysis of a Pollutant Flow Tracer Test in River using Radioactive Isotope)

  • 김기철;이종석
    • 한국콘텐츠학회논문지
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    • 제9권1호
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    • pp.400-406
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    • 2009
  • 본 연구에서는 하천에 유입된 오염물질의 거동 및 확산 특성을 파악하기 위하여 실제 하천에서 RI(Radioactive Isotope) 추적자를 이용하여 오염물 확산을 실측하고 그 결과를 수치모형과 비교분석하였다. 연구대상 수로구간은 금강 상류지역의 용담댐 부근 합류지점으로부터 하류로 약 2km구간에서 실험을 하였으며, 수치모형으로는 RMA-2(Resource Modeling Associates-2), RMA-4를 사용하였다. RI를 이용한 현장실험은 모델링을 적용한 지역과 동일 지역에서 실험을 실시하였고, 각 구간의 간격은 1km로 정하되 현장 사정에 따라 차이를 조금 두어 RI계측기인 NaI계측기를 통한 1초 간격의 농도 데이터를 계측하였다. 계측결과는 수치모형의 결과와 실제 하천에서의 확산범위 및 확산에 큰 영향을 미치는 확산계수 변화에 따른 농도 분포를 비교 분석하였다.

뇌졸중 환자의 보행능력에 따른 횡격막 두께와 폐기능 분석 (The Analysis on Diaphragm Thickness and Lung Function of Stroke Patients by Walking Ability)

  • 정주현;김난수
    • 대한물리의학회지
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    • 제6권4호
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    • pp.437-445
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    • 2011
  • Purpose : The purpose of this study was to analysis on diaphragm thickness and lung function of stroke patients by walking ability. Methods : We recruited thirty-five adults after stroke(20 male, 15 female) for our study. The subjects were divided into two groups; independent walking group(11 male, 9 female) and non-independent walking group(9 male, 6 female). Assessment of diaphragm thickness was performed using ultrasound in B-mode with a 7.5 MHz linea probe. During the experiment, the subject was seated in the chair. All subjects performed maximal expiratory flow maneuvers using a spirometer in order to determine the forced expiratory volume in 1 second ($FEV_1$), forced vital capacity(FVC), peak expiratory flow(PEF) and $FEV_1$/FVC. Chest expansion was measured with a tape-measure placed circumferentially around the chest wall at the xiphoid process. The collected data analyzed by independent t-test. Results : The diaphragm thickness were significant differences between the independent walking and nonindependent walking group. Values of forced vital capacity, forced expiratory volume at one second, peak expiratory flow in pulmonary function tests were significant differences between the independent walking and non-independent walking group. However, chest expansion were not significant differences in both of the group. Conclusion : This study showed that walking ability of stroke patients have influenced on diaphragm thickness and pulmonary function.