• 한국IT서비스학회지
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• 제13권4호
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• pp.109-122
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• 2014

Demand of spectrum resource is tremendously increasing recently and this trend will continues in the future due to the wide spread of IT services based on cloud computing and Internet of Things technology and as well as smart devices. Recently, spectrum sharing technology has drawn attention to the spectrum policy makers as a promising way to overcome the shortage problem of scarce spectrum resource. To succeed in commercialization of spectrum sharing technology, it is necessary to prospect the future business ecosystem of spectrum sharing and develop appropriate policies and laws at the same time along with the advance of spectrum sharing technology. The purpose of this paper is to analyze casual relationships between enablers in future business ecosystem of spectrum sharing and propose policies to vitalize spectrum sharing ecosystem based on a system dynamics causal map proposed in the previous research. With the causal map and system dynamics method, it is possible to analyze feedback loops exist in the business ecosystem of spectrum sharing and build policies which optimize positive dynamics in business ecosystem of spectrum sharing. As a result, policy leverages were found in four areas; spectrum supply, spectrum demand, spectrum quality and technology, and spectrum transaction cost. For those policy leverages, 13 policies were identified and intervention timing for each policy was discussed. Finally, the promotion policies of government and market participants to vitalize spectrum sharing ecosystem were discussed.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 2003년도 추계공동학술대회
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• pp.239-250
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• 2003

In this research, we propose a hybrid group decision support mechanism (H-GDSM) based on Fuzzy AHP (Analytic Hierarchy Process) and FCM (Fuzzy Cognitive Map). The AHP elicits a corresponding priority vector interpreting the preferred information among the decision makers. Corresponding vector was composed of the pairwise comparison values of a set of objects. Since pairwise comparison values are the judgments obtained from an appropriate semantic scale. However, AHP couldn't represent the causal relationship among information, which were used by decision makers. In contrast to AHP, FCM could represent the causal relationship among variables or information. Therefore, FCMs were successfully developed and used in several ill-structured domains, such as strategic decision-making, policy making, and simulations. Nonetheless, many researchers used subjective and voluntary inputs to simulate the FCM. As a result of subjective inputs, it couldn't avoid the rebukes of businessman. To overcome these limitations, we incorporated the Fuzzy membership functions, AHP and FCM into a H-GDSM. In contrast to current AHP methods and FCMs, the H-GDSM method developed herein could concurrently tackle the pairwise comparison involving causal relationships under a group decision-making environment. The strengths and contributions of our mechanism were 1) handling of qualitative knowledge and causal relationships, 2) extraction of objective input value to simulate the FCM, 3) multi-phase group decision support based on H-GDSM. To validate our proposed mechanism we developed a simple prototype system to support negotiation-based decisions in electronic commerce (EC).

• Asian-Australasian Journal of Animal Sciences
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• 제21권5호
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• pp.617-623
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• 2008

A fine-mapping method exploiting linkage disequilibrium was used to detect quantitative trait loci (QTL) on the X chromosome affecting milk production, body conformation and productivity traits. The pedigree comprised 22 paternal half-sib families of Black-and-White Holstein bulls in the Netherlands in a grand-daughter design for a total of 955 sons. Twenty-five microsatellite markers were genotyped to construct a linkage map on the chromosome X spanning 170 Haldane cM with an average inter-marker distance of 7.1 cM. A covariance matrix including elements about identical-by-descent probabilities between haplotypes regarding QTL allele effects was incorporated into the animal model, and a restricted maximum-likelihood method was applied for the presence of QTL using the LDVCM program. Significance thresholds were obtained by permuting haplotypes to phenotypes and by using a false discovery rate procedure. Seven QTL responsible for conformation types (teat length, rump width, rear leg set, angularity and fore udder attachment), behavior (temperament) and a mixture of production and health (durable prestation) were detected at the suggestive level. Some QTL affecting teat length, rump width, durable prestation and rear leg set had small numbers of haplotype clusters, which may indicate good classification of alleles for causal genes or markers that are tightly associated with the causal mutation. However, higher maker density is required to better refine the QTL position and to better characterize functionally distinct haplotypes which will provide information to find causal genes for the traits.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.92-96
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• 2015

Due to unique characteristics of small construction companies, safety management is comprised of complex problems (e.g., resources constraints, a lack of formalized management structures, low level of management safety commitment etc.). In order to understand causal interdependencies between safety factors at different system levels (regulation, organization, technical and individual), this paper aims to develop a system dynamics (SD) model of safety management in small construction companies. The purpose of the SD model is to better understand why small construction companies have low level of safety performance. A causal loop diagram (CLD) was developed based on literature, with an attempt to map causal relationships between variables. The CLD was then converted into stock and flow diagram for simulation. Various tests were conducted to build confidence in the model's ability to represent the reality. A number of policies were analyzed by changing the value of parameters. The value of a system dynamics approach to safety management in small construction companies is its ability to address joint effects of multiple safety risk factors on safety performance with a systems thinking perspective. By taking into account feedback loops and non-linear relationships, such a system dynamics model provides insights into the complex causes of relatively poor safety performance of small construction companies and improvement strategies.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1997년도 추계학술대회 학술발표 논문집
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• pp.247-251
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• 1997

FCM(Fuzzy Cognitive Map) is a fuzzy signed directed graph for representing causal reasoning which has fuzziness between causal concepts. Authors have already proposed FCM-based fault diagnostic scheme and verified its usefulness. However, the previously proposed scheme has the problem of lower diagnostic resolution as in the case of other qualitative approaches. In order to improve the diagnostic resolution, a concept of fuzzy number is introduced into the basic FCM-based fault diagnostic algorithm. By incorporation the fuzzy number into fault FCM models, quantitative information such as the transfer gain between the state variables can be effectively utilized for better diagnostic resolution. Furthermore, an enhanced TAM(Temporal Associative Memory) recall procedure and modified and modified pattern matching scheme are also proposed.

• 과학교육연구지
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• 제32권1호
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• pp.61-72
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• 2008

본 연구의 목적은 물의 순환에 대한 고등학생들의 시스템 사고의 정도를 알아보고, 학생들이 물의 순환에 대해 기술한 내용 중에서 지구시스템과 관련된 개념들은 어떤 것들이 있는지 알아보고자 하는 것이다. 연구 대상은 비평준화 지역인 포항시에서 성적이 중간 정도인 고등학교 3학년 학생 4명을 선정하여 물의 순환에 대한 질문지를 작성하게 하고 그 결과를 토대로 인과지도를 작성한 후 시스템 사고의 관점에서 분석하였다. 연구의 결과는 첫째, 학생들이 기술한 내용 중에 지구시스템과 관련된 개념은 모두 21개였으며, 이 중 과학적 개념 연결은 14개, 비과학적 개념 연결은 7개로 나타났다. 둘째, 학생들이 기술한 내용을 인과지도로 작성한 결과 피드백 루프가 완성된 학생은 A, C학생 2명 뿐 이었으며 그 중 C학생의 피드백 루프는 비과학적 개념 연결을 포함하고 있었다. 전체적으로 학생들이 물의 순환에 대하여 시스템 사고를 적절하게 수행하지 못하고 있거나 낮은 수준의 시스템 사고를 하고 있으며 내용에 대한 이해가 부족한 것으로 나타났다.

• 한국시스템다이내믹스학회:학술대회논문집
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• 한국시스템다이내믹스학회 2003년도 춘계학술대회발표논문집
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• pp.57-64
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• 2003

시스템 다이내믹스는 인과지도(Causal map)를 통한 시스템 이해를 그 출발점으로 한다. 특히 시스템 사고(systems thinking)는 저량-유량 흐름도를 통한 컴퓨터 시뮬레이션을 통하지 않고서 인과지도 분석만을 통한 시스템의 이해를 시도한다. 그러나 과연 인파지도만을 가지고 시스템을 동태적 변화를 이해/예측할 수 있는가에 관하여는 낙관적 전망과 부정적 전망이 혼재되어 있는 상황이다. 본 연구에서는 인과지도 구축을 통하여 시스템의 변화를 이해하는 데 있어서 어떠한 인지적 편향(bias)이 개입되는지를 탐색하고자 한다. 만일 심리적 편향이 존재한다면. 시스템 사고는 오류로부터 자유로울 수 없을 것이다. 본 연구에서는 이러한 오류의 존재를 탐색함으로써 시스템 사고의 제한정과 그 극복방안에 관하여 논의하고자 한다.(중략)

• 한국시스템다이내믹스연구
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• 제15권4호
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• pp.129-159
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• 2014

This Study discuss exploring normative-prescriptive factors after the themes on Organizational learning categorize two descriptive/explanatory-perspectives, prescriptive/normative dimension. The former would contain information processing model, theory of action, organizing in organization, while Senge's suggestion on Learning Organization may compose the latter. Each perspective is reconstructed and reinterpreted into the causal mapping relationship founded on system thinking and SD. Underlying on the former try to discovery validities of the latter. But this study only put forward the integral-dynamic model of organizational learning without empirical simulation.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1993년도 춘계공동학술대회 발표논문 및 초록집; 계명대학교, 대구; 30 Apr.-1 May 1993
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• pp.283-290
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• 1993

Cognitive map is used for structuring and analyzing complex and unstructured decision environments, and it is a tool for graphically representing interrelationships among a variety of factors. It is a representation of the subjective perception of individual decision maker. Usually it is constructed by a number of experts at group level. This paper presents the technique of building an accurate cognitive map through several tests about the preliminary generated one. This paper also proposes an approach for aggregating the causal intensities of multiple experts.

• 한국콘텐츠학회논문지
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• 제8권12호
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• pp.1-9
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• 2008

인과관계의 지식을 모델링하고 표현하며 추론하는 주요 형식화 방법의 하나인 퍼지인식도(Fuzzy Cognitive Map)는 주로 인과지식공학에 많이 사용되고 있다. 인과관계의 자연스럽고 쉬운 의사결정의 이해와 전후관계의 자연스러운 설명이라는 장점에도 불구하고 인과관계의 지식 모델링과 표현은 구현에 있어서 수학적인 적용의 모호함과 복잡한 알고리즘으로 인해 상호작용에 기반 한 구축 시스템을 찾아보기 어렵다. 본 논문에서는 인과지식 추론을 위한 퍼지 인식도의 구축 지원 시스템을 제시한다. 본 논문에서 제안하는 인과관계 추론 시스템은 다중 전문가의 지식을 반영하기 위해 지식을 점진적으로 반영하여 퍼지 인식도를 구축한다. 또한 전문가와의 상호작용을 통해 구현된 퍼지 인식도의 구조를 동적으로 디스플레이함으로써 사용자 지향적인 환경을 제공한다.