• Title/Summary/Keyword: Probabilistic Method.

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Impacts of Wind Power Integration on Generation Dispatch in Power Systems

  • Lyu, Jae-Kun;Heo, Jae-Haeng;Kim, Mun-Kyeom;Park, Jong-Keun
    • Journal of Electrical Engineering and Technology
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    • v.8 no.3
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    • pp.453-463
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    • 2013
  • The probabilistic nature of renewable energy, especially wind energy, increases the needs for new forms of planning and operating with electrical power. This paper presents a novel approach for determining the short-term generation schedule for optimal operations of wind energy-integrated power systems. The proposed probabilistic security-constrained optimal power flow (P-SCOPF) considers dispatch, network, and security constraints in pre- and post-contingency states. The method considers two sources of uncertainty: power demand and wind speed. The power demand is assumed to follow a normal distribution, while the correlated wind speed is modeled by the Weibull distribution. A Monte Carlo simulation is used to choose input variables of power demand and wind speed from their probability distribution functions. Then, P-SCOPF can be applied to the input variables. This approach was tested on a modified IEEE 30-bus system with two wind farms. The results show that the proposed approach provides information on power system economics, security, and environmental parameters to enable better decision-making by system operators.

Design of Probabilistic Model for Optimum Manpower Planning in R&D Department (연구개발 부문 적정인력 산정을 위한 확률적 모형설계에 관한 연구)

  • Kim, ChongMan;Ahn, JungJin;Kim, ByungSoo
    • Journal of Korean Society for Quality Management
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    • v.41 no.1
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    • pp.149-162
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    • 2013
  • Purpose: The purpose of this study was to design of a probabilistic model for optimum manpower planning in R&D department by Montecarlo simulation. Methods: We investigate the process and the requirement of manpower planning and scheduling in R&D department. The empirical distributions of necessary time and manpower for R&D projects are developed. From the empirical distributions, we can estimate a probability distribution of optimum manpower in R&D department. A simulation method of estimating the probability distribution of optimum manpower is considered. It is a useful tool for obtaining the sum, the variance and other statistics of the distributions. Results: The real industry cases are given and the properties of the model are investigated by Montecarlo Simulation. we apply the model to the research laboratory of the global company, and investigate and compensate the weak points of the model. Conclusion: The proposed model provides various and correct information such as average, variance, percentile, minimum, maximum and so on. A decision maker of a company can easily develop the future plan and the task of researchers may be allocated properly. we expect that the productivity can be improved by this study. The results of this study can be also applied to other areas including shipbuilding, construction, and consulting areas.

Range Detection of Wa/Kwa Parallel Noun Phrase by Alignment method (정렬기법을 활용한 와/과 병렬명사구 범위 결정)

  • Choe, Yong-Seok;Sin, Ji-Ae;Choe, Gi-Seon;Kim, Gi-Tae;Lee, Sang-Tae
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2008.10a
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    • pp.90-93
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    • 2008
  • In natural language, it is common that repetitive constituents in an expression are to be left out and it is necessary to figure out the constituents omitted at analyzing the meaning of the sentence. This paper is on recognition of boundaries of parallel noun phrases by figuring out constituents omitted. Recognition of parallel noun phrases can greatly reduce complexity at the phase of sentence parsing. Moreover, in natural language information retrieval, recognition of noun with modifiers can play an important role in making indexes. We propose an unsupervised probabilistic model that identifies parallel cores as well as boundaries of parallel noun phrases conjoined by a conjunctive particle. It is based on the idea of swapping constituents, utilizing symmetry (two or more identical constituents are repeated) and reversibility (the order of constituents is changeable) in parallel structure. Semantic features of the modifiers around parallel noun phrase, are also used the probabilistic swapping model. The model is language-independent and in this paper presented on parallel noun phrases in Korean language. Experiment shows that our probabilistic model outperforms symmetry-based model and supervised machine learning based approaches.

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A Probabilistic Analysis on the Repair and Replacement Cost of Educational Facilities (교육시설물의 수선교체비용에 대한 확률론적 분석 연구)

  • Yu, Yeong-jin;Son, Kiyoung;Kim, Ji-Myong;Kim, Taihui
    • Journal of the Korean Institute of Educational Facilities
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    • v.25 no.1
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    • pp.3-12
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    • 2018
  • Educational facilities are more uncertain about maintenance costs due to their comprehensive and long life-cycle compared to commercial buildings. In addition, maintenance of the existing post management system can not maintain the original function of education facilities continuously and economically. In order to overcome this problem, it is necessary to analyze the repair and replacement cost for the uncertainty factor in maintenance. This study propose a model to determine repair and maintenance cost and cycle of educational facility based on probabilistic estimation concept. For the analysis, Monte Carlo simulation, a probabilistic analysis method, was applied based on the repair and maintenance history data of the educational facilities in Florida. The results of this study can be used as a guideline for quantitative facility management and facility management research.

Probabilistic Analysis of Lifetime Extreme Live Loads in Office Buildings (사무실의 사용기간 최대 적재하중에 대한 확률론적 분석)

  • 김상효;조형근;배규웅;박흥석
    • Computational Structural Engineering
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    • v.3 no.1
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    • pp.109-116
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    • 1990
  • Live load data in domestic office buildings have been collected in a systematic manner. Based on surveyed data, equivalent uniformly distributed load intensities, which produce the same load effect as the actual spatially varying, live load, have been obtained for various structural members (such as slab, beam, column, etc. ). Influence surface method has been employed to compute load effects under real live load, including beam moment, slab moment as well as axial force in column. The results have been examined to find probabilistic characteristics and relationship between influence area and load intensity (or coefficient of variation). The results were also compared with other survey results and found to be reasonable. Based on the probabilistic load models obtained, the lifetime extreme values have been analyzed and compared with current design loads. Tentative equations applicable to decide more rational design loads are also suggested as functions of influence area.

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A meso-scale approach to modeling thermal cracking of concrete induced by water-cooling pipes

  • Zhang, Chao;Zhou, Wei;Ma, Gang;Hu, Chao;Li, Shaolin
    • Computers and Concrete
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    • v.15 no.4
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    • pp.485-501
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    • 2015
  • Cooling by the flow of water through an embedded cooling pipe has become a common and effective artificial thermal control measure for massive concrete structures. However, an extreme thermal gradient induces significant thermal stress, resulting in thermal cracking. Using a mesoscopic finite-element (FE) mesh, three-phase composites of concrete namely aggregate, mortar matrix and interfacial transition zone (ITZ) are modeled. An equivalent probabilistic model is presented for failure study of concrete by assuming that the material properties conform to the Weibull distribution law. Meanwhile, the correlation coefficient introduced by the statistical method is incorporated into the Weibull distribution formula. Subsequently, a series of numerical analyses are used for investigating the influence of the correlation coefficient on tensile strength and the failure process of concrete based on the equivalent probabilistic model. Finally, as an engineering application, damage and failure behavior of concrete cracks induced by a water-cooling pipe are analyzed in-depth by the presented model. Results show that the random distribution of concrete mechanical parameters and the temperature gradient near water-cooling pipe have a significant influence on the pattern and failure progress of temperature-induced micro-cracking in concrete.

Estimating the required storage inventory of a container terminal considering the variance of a containership's load size (본선 작업물량의 변동을 고려한 컨테이너터미널의 소요장치량 산정)

  • Park, Byung-In;Bae, Jong-Wook
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.261-267
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    • 2006
  • The required storage inventory is a very important decision variable which determines the storage capacity of a container terminal. Generally, the required storage inventory is dependent upon such factors as ship headway, allowable dwell time of containers, loading/unloading time per ship, and so on. Until now, the required storage inventory is estimated under the assumption that the factors are deterministic in several studies. However, this study proposes how to estimate a required storage inventory satisfying the required service level under the assumption that a containership's load size is probabilistic. Numerical experiments, which use a simulation show that the proposed method can estimate more adequately the maximum storage inventory than other methods under a probabilistic environment.

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The Recognition of Printed Chinese Characters using Probabilistic VQ Networks and hierarchical Structure (확률적 VQ 네트워크와 계층적 구조를 이용한 인쇄체 한자 인식)

  • Lee, Jang-Hoon;Shon, Young-Woo;Namkung, Jae-Chan
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.7
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    • pp.1881-1892
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    • 1997
  • This paper proposes the method for recognition of printed chinese characters by probabilistic VQ networks and multi-stage recognizer has hierarchical structure. We use modular neural networks, because it is difficult to construct a large-scale neural network. Problems in this procedure are replaced by probabilistic neural network model. And, Confused Characters which have significant ratio of miss-classification are reclassified using the entropy theory. The experimental object consists of 4,619 chinese characters within the KSC5601 code except the same shape but different code. We have 99.33% recognition rate to the training data, and 92.83% to the test data. And, the recognition speed of system is 4-5 characters per second. Then, these results demonstrate the usefulness of our work.

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Improvement of Okamoto-Uchiyama Probabilistic Public Key Cryptosystem (Okamoto-Uchiyama 확률 공개키 암호 방식의 효율성 개선)

  • Choi, Duk-Hwan;Kim, Hyun-Jue;Choi, Seung-Bok;Won, Dong-Ho
    • Journal of KIISE:Information Networking
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    • v.29 no.4
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    • pp.346-351
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    • 2002
  • We improve a new probabilistic public key cryptosystem, in which the one wav function was defined only on the discrete logarithmic functions, proposed by Okamoto and Uchiyama. The plaintexts are calculated from the modular product of two these functions, one of which has a fixed value depending on a given public key. The improvement is achieved by a well-chosen public key assuming an unit element 1 as the fixed function value. Because it is possible to reduce the number of operations at the decryption. Also the concrete method for a public key of our improved scheme is suggested.

Personalized Media Control Method using Probabilistic Fuzzy Rule-based Learning (확률적 퍼지 룰 기반 학습에 의한 개인화된 미디어 제어 방법)

  • Lee, Hyeong-Uk;Kim, Yong-Hwi;Lee, Tae-Yeop;Park, Gwang-Hyeon;Kim, Yong-Su;Jo, Jun-Myeon;Byeon, Jeung-Nam
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2006.11a
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    • pp.25-28
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    • 2006
  • 사용자 의도 파악 (intention reading) 기술은 스마트 홈과 같은 복잡한 유비쿼터스(ubiquitous) 환경에서 사용자에게 보다 편리하고 개인화된(personalized) 서비스 제공이 가능하도록 해준다. 또한 학습 기능(learning capability)은 지식 발견(knowledge discovery)의 관점에서 의도 파악 기술의 핵심 요소 기술의 하나로 자리 매김 하고 있다. 본 논문에서는 스마트 홈 환경에서 제공 가능한 개인화된 서버스(personalized service) 중의 하나로, 개인화된 미디어 제어 방법에 대한 내용을 다룬다. 특히, 이러한 사람의 행동 패턴과 같은 데이터는 패턴 분류의 관점에서 구분해야 할 클래스(class)에 비해 입력 정보가 불충분할 경우가 많으므로 비일관적인(inconsistent) 데이터가 많으므로, 퍼지 논리(fuzzy logic)와 확률(probability)의 개념을 효과적으로 병행해야 의미 있는 지식을 추출해 낼 수 있다. 이를 위하여 반복 퍼지 지도 클러스터링 (IFCS; Iterative Fuzzy Clustering with Supervision) 알고리즘에 기반하여 주어진 데이터 패턴으로부터 확률적 퍼지 룰(probabilistic fuzzy rule)을 얻어 내는 방법에 대해 설명한다. 또한 이를 포함하는 학습 제어 시스템을 통해 개인화된 미디어 서비스를 추천해 줄 수 있는 방법에 대해서 설명하도록 한다.

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