• Industrial Engineering and Management Systems
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• 제15권2호
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• pp.143-147
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• 2016

Uncertainty appears not only in real quantities but also in complex quantities. Complex uncertain process is essentially a sequence of complex uncertain variables indexed by time. In order to describe complex uncertain process, a formal definition of complex uncertain distribution is given in this paper, as well as the concepts of independence and variance. In addition, some properties of complex uncertain integral are presented.

• Journal of Information Technology Applications and Management
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• 제14권4호
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• pp.139-158
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• 2007

Information sharing is key to effective supply chain management. In reality, however, it is impossible to get perfect information. Accordingly, only uncertain information can be accessed in business environment, and thus it is important to deal with the uncertainties of information in managing supply chains. This study adopts meteorological forecast as a typical uncertain information. The meteorological events may affect the demands for various weather-sensitive goods, such as beer, ices, clothes, electricity etc. In this study, a beer distribution game is modified by introducing meterological forecast information provided in a probabilistic format. The behavior patterns of the modified beer supply chains are investigated. for two conditions using the weather forecast with or without an information sharing. A value score is introduced to generalize the well-known performance measures employed in the study of supply chains, i.e.. inventory, backlog, and deviation of orders. The simulation result showed that meterological forecast information used in an information sharing environment was more effective than without information sharing, which emphasizes the synergy of uncertain information added to the information sharing environment.

• Industrial Engineering and Management Systems
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• 제12권1호
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• pp.2-8
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• 2013

Uncertainty theory is a branch of mathematics based on normolity, duality, subadditivity and product axioms. Uncertain process is a sequence of uncertain variables indexed by time. Canonical Liu process is an uncertain process with stationary and independent increments. And the increments follow normal uncertainty distributions. Uncertain differential equation is a type of differential equation driven by the canonical Liu process. Stability analysis on uncertain differential equation is to investigate the qualitative properties, which is significant both in theory and application for uncertain differential equations. This paper aims to study stability properties of linear uncertain differential equations. First, the stability concepts are introduced. And then, several sufficient and necessary conditions of stability for linear uncertain differential equations are proposed. Besides, some examples are discussed.

• 한국정보과학회논문지:소프트웨어및응용
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• 제37권2호
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• pp.148-154
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• 2010

불확실성 데이터베이스의 의미론 정의는 보통 주어진 불확실성 데이터베이스를 여러 개의 관계형데이터베이스로 변환하는 산술적 접근방법을 취한다. 이 논문에서는 불확실성데이터베이스를 논리이론으로 변환하는 논리적 접근방법을 통해서 불확실성 데이터베이스의 의미론을 정의하고자 한다. 본 논문에서 제안하는 의미론의 가장 특징적인 면은 기존의 논리적 접근방법에서 사용해온 명제논리 대신에 선형논리를 논리적 근간으로 이용한다는 점이다. 선형논리는 논리식을 불변진리가 아닌 소비가능한 자원으로 해석하기 때문에 불확실성 데이터베이스의 의미론을 정의하는데 적합하다. 본 논문의 핵심 결과는 선형논리에 기반한 불확실성 데이터베이스의 의미론이 산술적 접근방식에서 설명하는 불확실성 데이터베이스의 의미론과 동등하다는 것이다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.571-574
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• 2005

This paper gives some sufficient conditions for a given polyhedral set which is represented as a set of linear inequalities to be positive D-invariant for uncertain linear discrete-time systems in the case such that the systems matrices depend linearly on uncertain parameters whose ranges are given intervals. Further, the results will be applied to uncertain linear continuous systems in the sense of the above by using Euler approximation.

• Journal of the Korean Data and Information Science Society
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• 제6권2호
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• pp.17-27
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• 1995

제약 조건 만족의 관점에서 불확실한 지식을 표현하고 처리하는 방법을 제안하였다. 등식이나 부등식은 만족되어야 할 제약 조건들이며, 제약 조건들은 수리 논리식으로 표현될 수 있는데 이들은 주어진 수리 논리식들의 집합에 대한 만족성을 계산하는 제약 조건 해결 프로그램에 의해 답을 얻을 수 있다. 불확실성을 포함한 규칙 기반 시스템들은 확률론의 초보적인 내용을 응용하여 표현되는데, 이 경우 제약 조건 해결 프로그램으로 효율적인 결과를 얻을 수 있다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.117-119
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• 1997

We consider the control design for nonlinear uncertain systems. The uncertainty is mismatched and possibly fast time-varying. Within the suitable range of the uncertainty the control is valid. No statistical information on uncertainty is imposed. Only the possible bound of the uncertain parameter is known and the control design is based on Lyapunov approach.

• Journal of the Korean Data and Information Science Society
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• 제8권1호
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• pp.1-7
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• 1997

전문가 시스템에서의 추론은 주로 IF-THEN 형태의 규칙을 기반으로 하는 지식베이스에 기초한다. 그러나, 한의 전문가 시스템의 지식은 불확실한 지식 특히 애매한 개념의 지식을 많이 포함하고 있으므로 이에 대한 처리가 요구된다. 본 논문에서는 한의 진단 과정을 추론에 기준하여 분석하고 한의 진단 과정에서 발생하는 불확실한 진단 지식을 제약 조건 논리 프로그래밍언어의 일종인 CLP( R ) 언어를 이용하여 표현하고 처리하는 방법을 제안하였다.

• 대한기계학회논문집
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• 제18권6호
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• pp.1542-1550
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• 1994

For a class of singularly perturbed uncertain system, an output feedback control law is designed. The controller structure is designed based on the uncertain reduced-order system, and the controller parameters are determined by information on the reduced-order and full-order systems. It has been shown that the reduces-order system with the designed controller possesses a stability property(specifically, a global uniform attractivity). Furthermore, the stability property of this control scheme is robust with respect to singular perturbation ; i.e., the full-order system, subject to the same controller, possesses the global uniform attractivity, provided the singular perturbation parameter $\mu<\mu^{*}$, where a threshold value $\mu^{*}$ can be computed from the information available on the full-order system.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권6호
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• pp.2986-2999
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• 2019

The uncertainties of the uncertain graph make the traditional definition and algorithms on mining dense graph for certain graph not applicable. The subgraph obtained by maximizing expected density from an uncertain graph always has many low edge-probability data, which makes it low reliable and low expected edge density. Based on the concept of ${\beta}$-subgraph, to overcome the low reliability of the densest subgraph, the concept of optimal ${\beta}$-subgraph is proposed. An efficient greedy algorithm is also developed to find the optimal ${\beta}$-subgraph. Simulation experiments of multiple sets of datasets show that the average edge-possibility of optimal ${\beta}$-subgraph is improved by nearly 40%, and the expected edge density reaches 0.9 on average. The parameter ${\beta}$ is scalable and applicable to multiple scenarios.