• 제목/요약/키워드: Preference ordering

검색결과 26건 처리시간 0.023초

다목적 유전자알고리즘을 이용한 Tank 모형 매개변수 최적화(II): 선호적 순서화의 적용 (Optimization of Tank Model Parameters Using Multi-Objective Genetic Algorithm (II): Application of Preference Ordering)

  • 구보영;김태순;정일원;배덕효
    • 한국수자원학회논문집
    • /
    • 제40권9호
    • /
    • pp.687-696
    • /
    • 2007
  • 본 연구는 다목적 유전자알고리즘을 이용하여 Tank 모형의 매개변수를 추정하는데 있어서 선호적순서화(preference ordering)를 적용한 연구로써, 목적함수의 개수가 여러 개인 경우에 발생할 수 있는 파레토최적화의 단점을 해결하기 위한 것이다. 최적화를 위한 목적함수는 모두 4가지를 사용하였으며, 선호적순서화를 통해서 구한 2차 효율성(2nd order efficiency)을 가지면서 정도(degree)가 3인 4개의 해 중에서 1개의 해만을 최우선해로 선정하였다. NSGA-II로 도출된 최우선해의 적합성을 살펴보기 위해서, 자동보정방법인 Powell 방법과 SGA(simple genetic algorithm)를 매개변수 자동보정 방법으로 이용하고 하나의 단일목적함수로 사용해서 최적화한 결과와 비교해보았으며, 비교결과 다목적 유전자 알고리즘을 4개의 목적함수에 모두 적용해서 한번에 도출된 매개변수를 이용한 결과가 보정기간뿐만 아니라 검정기간에 대해서도 비교적 양호한 결과를 나타내는 것으로 나타났다.

H-induced Magnetism at Stepped Si (100) Surface

  • Lee, Jun-Ho;Cho, Jun-Hyung
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
    • /
    • pp.211-211
    • /
    • 2012
  • Using spin-polarized density-functional theory calculations, we find that the existence of either Peierls instability or antiferromagnetic spin ordering is sensitive to hydrogen passivation near the step. As hydrogens are covered on the terrace, the dangling bond electrons are localized at the step, leading to step-induced states. We investigate the competition between charge and spin orderings in dangling-bond (DB) wires of increasing lengths fabricated on an H-terminated vicinal Si(001) surface. We find antiferromagnetic (AF) ordering to be energetically much more favorable than charge ordering. The energy preference of AF ordering shrinks in an oscillatory way as the wire length increases. This oscillatory behavior can be interpreted in terms of quantum size effects as the DB electrons fill discrete quantum levels.

  • PDF

목표고객의 연령속성을 이용한 협력적 필터링 추천 시스템의 정확도 향상 (Accuracy improvement of a collaborative filtering recommender system using attribute of age)

  • 이석환;박승헌
    • 대한안전경영과학회지
    • /
    • 제13권2호
    • /
    • pp.169-177
    • /
    • 2011
  • In this paper, the author devised new decision recommendation ordering method of items attributed by age to improve accuracy of recommender system. In conventional recommendation system, recommendation order is decided by high order of preference prediction. However, in this paper, recommendation accuracy is improved by decision recommendation order method that reflect age attribute of target customer and neighborhood in preference prediction. By applying decision recommendation order method to recommender system, recommendation accuracy is improved more than conventional ordering method of recommendation.

산림작업에 따른 임분의 시각선호도 평가 (Visual Preference Evaluation of Forest Stands toward Forest Working Systems)

  • 송형섭;오도교
    • 농업과학연구
    • /
    • 제30권2호
    • /
    • pp.139-147
    • /
    • 2003
  • The main purpose of this study is to obtain forest scenic beauty management informations toward forest working systems in pinus densiflora forest stands, etc. To get these information, visual preference and spatial image analysis methods are used. 25 different alternatives were simulated to visualize on basis of actual forest working methods with taken photos from May to July, 2003. The options were illustrated as photos produced by computer software. Respondents' ratings for 25 landscape scenes were obtained by interview survey method. Each alternatives were evaluated by forest major student group with total 103 respondents after reliability test. Visual preference evaluation was used 10 point rating scale. Spatial images of 12 alternatives were measured by 12 semantic differential scale. In general, the respondents preferred refreshing and ordering forest stand after forest working to natural forest stand before forest working. High visual preference for forest density produces 400-600 trees/ha in small diameter class forest stands. Regarding visual preference according to pavement type of trail, soil trail is ranked high. Visual preference for cutting area ranks mature forest stand and visual preference for trail slope cover type ranks shrub with grass as relatively high on the preference scale. Through the factor analysis, spatial images of 12 coniferous forest stands are classified as 'ordered opened' and 'beautiful healthy'. Results indicate how to conduct forest working systems for forest scenic beauty management.

  • PDF

그래프 모형을 이용한 지수분포 모수들의 기하평균 비교에 관한 연구 (On Multiple Comparison of Geometric Means of Exponential Parameters via Graphical Model)

  • 김대황;김혜중
    • 응용통계연구
    • /
    • 제19권3호
    • /
    • pp.447-460
    • /
    • 2006
  • 본 연구에서는 확률모형의 모수로부터 얻어지는 여러 형태의 함수간의 크기를 다중 비교 하는 방법을 제안하고자 한다. 이 방법은 비교대상인 모수 함수 간의 선호확률을 베이지안 방법으로 추정하고, 이들로부터 얻어지는 선호행렬을 이용한 새로운 다중비교법이다. 이러한 방법의 제안에 필요한 이론과 비교기준을 고안하였으며, 응용 예로 제안된 방법을 s의 독립인 지수분포 모수의 기하평균 크기 비교에 적용하였다.

Post-TPP Trade Policy Options for ASEAN and its Dialogue Partners: "Preference Ordering" Using CGE Analysis

  • Ji, Xianbai;Rana, Pradumna B.;Chia, Wai-Mun;Li, Changtai
    • East Asian Economic Review
    • /
    • 제22권2호
    • /
    • pp.177-215
    • /
    • 2018
  • Trump's withdrawal from the Trans-Pacific Partnership (TPP) and his "America First" trade agenda ignite a second round of interest in mega-free trade agreements in the Asia-Pacific. Countries are evaluating alternative trade policy actions in a post-TPP era. Using national real GDP gains estimated by a modified GTAP model to construct "preference ordering" for 10 Association of Southeast Asian Nations members and their six regional dialogue partners, this paper comes up with several policy-oriented findings. First, when multilateral agreements are not possible, countries are better off with a regional trading agreement than without one. Second, the Regional Comprehensive Economic Partnership is likely to have higher beneficial impacts than the Comprehensive and Progressive Agreement for Trans-Pacific Partnership. Third, for dual-track countries, implementing both agreements is better than each separately. Fourth, impacts of open regionalism are likely to be higher than those of a closed and reciprocal one. Going forward, this paper argues that countries should adopt a "multi-track, multi-stage" approach to trade policy.

A Bayesian Approach to Dependent Paired Comparison Rankings

  • Kim, Hea-Jung;Kim, Dae-Hwang
    • 한국통계학회:학술대회논문집
    • /
    • 한국통계학회 2003년도 춘계 학술발표회 논문집
    • /
    • pp.85-90
    • /
    • 2003
  • In this paper we develop a method for finding optimal ordering of K statistical models. This is based on a dependent paired comparison experimental arrangement whose results can naturally be represented by a completely oriented graph (also so called tournament graph). Introducing preference probabilities, strong transitivity conditions, and an optimal criterion to the graph, we show that a Hamiltonian path obtained from row sum ranking is the optimal ordering. Necessary theories involved in the method and computation are provided. As an application of the method, generalized variances of K multivariate normal populations are compared by a Bayesian approach.

  • PDF

Neutrinoless Double Beta Decay and Light Sterile Neutrino

  • Jang, C.H.;Kim, B.J.;Ko, Y.J.;Siyeon, K.
    • Journal of the Korean Physical Society
    • /
    • 제73권11호
    • /
    • pp.1625-1630
    • /
    • 2018
  • The recent neutrino experiment results show a preference on normal mass ordering of neutrinos. The global efforts to search for neutrinoless double beta decays undergo a broad gap with the approach to the prediction in three-neutrino framework based on the normal ordering. Current research is to show that it is possible to find a neutrinoless double beta decay signal even with normal ordered neutrino masses. We propose the existence of light sterile neutrino as a solution to the higher effective mass of electron neutrino expected by experiments under operation. A few short-baseline oscillation experiments gave rise to exclusion bound to the mass of sterile neutrino and its mixing with the lightest neutrino. It is demonstrated that results of neutrinoless double beta decays can also narrow down the ranges of the mass and the mixing angle of sterile neutrino.

다목적 유전자알고리즘을 이용한 Tank 모형 매개변수 최적화(I): 방법론과 모형구축 (Optimization of Tank Model Parameters Using Multi-Objective Genetic Algorithm (I): Methodology and Model Formulation)

  • 김태순;정일원;구보영;배덕효
    • 한국수자원학회논문집
    • /
    • 제40권9호
    • /
    • pp.677-685
    • /
    • 2007
  • 본 연구의 목적은 개념적인 강우-유출모형인 Tank 모형의 매개변수를 산정하기 위한 다목적 유전자알고리즘의 적용성을 평가하는 것이다. 다목적 유전자알고리즘 기법으로는 최근에 가장 많이 사용되는 기법중의 하나인 NSGA-II를 채택하여 Tank 모형과 결합하였으며, 4가지 목적함수(유출용적오차, 평균제곱근 오차, 고수유량 평균제곱근 오차 및 저수유량 평균제곱근 오차)값을 최소화하는 형태의 목적함수를 적용하였다. NSGA-II는 목적함수의 개수가 많아지면 한 번의 실행에 의해 굉장히 많은 수의 파레토최적해를 구하는 단점을 가지고 있기 때문에 구해진 파레토최적해 중에서 어떤 해가 최우선해 인지를 결정해야 할 필요가 있으며, 이러한 고차원적인 의사결정을 위하여 선호적순서화(preference ordering) 기법을 적용하였다. NSGA-II를 이용하여 Tank모형의 매개변수를 추정할 때 초기조건이 최적화과정에 미칠 수 있는 영향을 최소화하기 위해 세대수(generation number)와 개체군의 크기(population size)에 대한 민감도분석을 수행하였다. 분석결과 Tank모형의 매개변수 최적화를 위한 세대수와 개체군 크기의 초기 값을 각각 900번과 1000개로 선정하는 것이 적합한 것으로 나타났다.

A Conversation Preference Profile for Web Services in Mobile Environment

  • Lee Kang-Chan;Lee Won-Suk;Jeon Jong-Hong;Lee Seung-Yun;Park Jong-Hun
    • Journal of information and communication convergence engineering
    • /
    • 제4권1호
    • /
    • pp.1-4
    • /
    • 2006
  • Recently Web Services choreography working group of W3C has published the working draft on WSCDL (Web Services Choreography Description Language) version 1.0 which defines reusable common rules to govern the ordering of exchanged messages between Web Services participants. This paper considers a computing environment where mobile clients are interacting with Web Services providers based on a WSCDL specification. In order to effectively cope with the user and device mobility of such an environment, in this paper we present an ongoing work to develop a framework through which a mobile client can specify its preference on how conversation should take place. The proposed framework provides a flexible means for mobile clients to minimize the number of message exchanges while allowing them to adhere to the required choreography.