• Atmosphere
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• v.30 no.2
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• pp.141-154
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• 2020

Seasonal forecast is growing in demand, as it provides valuable information for decision making and potential to reduce impact on weather events. This study examines how operational climate prediction systems can be reliable, producing the probability forecast in seasonal scale. A reliability diagram was used, which is a tool for the reliability by comparing probabilities with the corresponding observed frequency. It is proposed for a method grading scales of 1-5 based on the reliability diagram to quantify the reliability. Probabilities are derived from ensemble members using hindcast data. The analysis is focused on skill for 2 m temperature and precipitation from climate prediction systems in KMA, UKMO, and ECMWF, NCEP and JMA. Five categorizations are found depending on variables, seasons and regions. The probability forecast for 2 m temperature can be relied on while that for precipitation is reliable only in few regions. The probabilistic skill in KMA and UKMO is comparable with ECMWF, and the reliabilities tend to increase as the ensemble size and hindcast period increasing.

• Journal of Korean Society of Rural Planning
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• v.16 no.3
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• pp.117-129
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• 2010

The purpose of this paper is to develop a web-based information system for rural settlement environment diagnosis which is useful to apply the village based evaluation for new rural development projects. To achieve this purpose, this study performed : 1) analyzing the business process in the field of rural settlement environment diagnosis, 2) designing the data flow diagram and the database based on settlement environment diagnostic indices(SEDI), and 3) developing the system using APM (Apache, PHP, and MySQL) of web-system development environment. The developed system was applied to the study rural villages for testing of efficient and logical working. Users of the system, such as, researchers, decision makers, and rural residents, can input directly the village data to diagnose through a file format of Excel in MS Office. Futhermore, they can analyze the visual results with graphic and graph types, simultaneously. From the results of this study, it showed that the developed system enables decision-makers not only to assist the planning process of the rural village development project, but also to improve the level of information technology in the research and planning field concerning with rural development.

• Journal of IKEEE
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• v.8 no.1 s.14
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• pp.22-32
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• 2004

In this paper, we proposed MOVAG(Multi Output Value Array Graphs) based on OVAG by Honghai Jiang to construct multiple valued logic function The MDD(Muliple-valued Decision Diagra) needs many processing time and efforts in circuit design for given multi-variable function by D.M.Miller, and we designed a MOVAG which has reduce the data processing time and low complexity. We propose the construction algorithm and input matrix selection algorithm and we designed the multiple-valued logic circuit using T-gate and verified by simulation results.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.1
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• pp.41-48
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• 1999

This paper presents a production method to GRM coefficients which is consists of 3n polarities to n variables over GF(3). General production method is searching for transformation matrix for a single variable and then kronecker products for n times. This paper presents a production method of GRM coefficients using DD(Decision Diagrma). Change of coefficients to a single variable are apply to DD and extended to n variables.

• Korean System Dynamics Review
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• v.15 no.2
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• pp.75-96
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• 2014

The purpose of this paper is to analyze the functional changes of local educational authority policy based on the systems thinking perspective using causal loop diagrams. In the past, the main function of the local educational authority was to manage and supervise schools. Through this policy, local educational authority would be transformed into a support agency. However, this policy did not achieve the goal, was to cause confusion and require improvement. This study shows structured causes of the problem based on systems thinking. These diagrams make it possible for educational policy makers to provide ideas, although they have some complicated environment. The findings indicate that based on systems thinking in this policy can help those who related to policy decision than existing diagnosis method.

• The Transactions of the Korea Information Processing Society
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• v.7 no.7
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• pp.2169-2178
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• 2000

This paper proposes the structure of an agent and rules for fault detection and location on LAN. To find out a reason of critical fault incurred LAN, collision detection rule, error detection rule, broadcast detection rule, system location rule, and Internet application location rule ar shown. Also, the structure of multi-agent system and state transition diagram is portrayed to have connectivity with he set of rules. To verify availability of proposed rules, the process to find a faulty system is shown by monitoring and analyzing the LAN fault occurrences from the proposed set of rules. Such an rule based agent system is helpful to an Internet manager to solve a reason of fault and make ad decision from gathering management information.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.4
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• pp.23-30
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• 2013

Reliability Centered Maintenance(RCM) is one of most widely used methods in the modern power system to schedule a maintenance cycle and determine the priority of inspection. A precedence study for the new structure of rearranged system should be performed due to introduction of additional installation. This paper proposes a new method to evaluate the priority of maintenance and inspection of the power system facilities. In order to calculate that risk index, it is required that the reliability block diagram should be analyzed for the power system. Additionally, a fault cause analysis is also performed through the event-tree analysis.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.546-549
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• 1998

다치결정도 (multiple-valued decision diagram : MDD) 와 순서화된 다치결정도 (ordered MDD:OMDD)는 다치논리함수의 표현에 폭넓게 사용된다. p치 n변수인 경우 p/sup (n-1)/으로 증가하는 노드의 수는 ROMDD(reduced OMDD)를 사용하여 현저하게 감소시킬 수 있다. 그러나 다치와 다변수의 경우에는 더욱 많은 공정을 수반하게 된다. 이러한 단점을 보완하기 위해 honghai jiang이 제안한 2치시스템에서의 input implict/output explicit 관계를 갖는 OVAG(output value array graph)를 사용하여 다치논리함수를 표현한다. 그리고 MDD 표현이 어려운 상황에서 MOVAG(multi OVAG)를 사용하여 보다 쉽게 출력값을 배열하는 그래프를 이끌어 낼 수 있다. 본 논문에서는 MOVAG의 구성방법과 회로에서 MOVAG로으 변환에 대한 알고리듬을 제안하였고, 알고리듬에 의한 결과를 MDD와 비교하여 노드수 감소에 따르는 처리속도가 개선됨을 검증하였다.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.3
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• pp.11-22
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• 1997

This paper presents the design and implementation of an efficient algorithm for detecting untestable paths in multi-level circuits. Transforming multi-level circuit into a multiplexor-based one through BDD(binary decision diagram)construction, the proposed algorithm detects untestable paths in the transformed circuits. By constructing ENF (equivalent normal form) only for reconvergent paths, the proposed system detects and removes untestable paths efficiently in terms of the run-time and memory usage. Experimental results for MCNC/ISCAS benchmark circuits show that the system efficiently detects and removes untestable paths. The run-time and memory usage have been reduced by 37.7% and 60/9%, respectively, comapred to the previous methods.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 1999.05a
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• pp.75-79
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• 1999

다치결정도(Multiple-valued Decision Diagram : MDD)와 순서화된 다치결정도(Ordered MDD : OMDD)는 다치논리함수의 표현에 폭넓게 사용된다. p치 n변수 인 경우 p$^{(n-1)}$ 으로 증가하는 노드의 수는 ROMDD(Reduced OMDD)를 사용하여 현저하게 감소시킬 수 있다. 그러나 다치와 다변수의 경우에는 더욱 많은 공정을 수반하게 된다. 이러한 단점을 보완하기 위해 Honghai Jiang이 제안한 2치시스템에서의 input implict/output explicit 관계를 갖는 OVAG(Output Value Array Graph)를 사용하여 다치논리함수를 표현한다. 고리고 MDD 표현이 어려운 상황에서 MOVAG(Multi OVAG)를 사용하여 보다 쉽게 출력값을 배열하는 그래프를 이끌어 낼 수 있다. 본 논문에서는 MOVAG의 구성방법과 회로에서 MOVAG로의 변환에 대한 알고리즘을 제안하였고, 알고리즘에 의한 결과를 MDD와 비교하여 노드수 감소에 따르는 처리속도가 개선됨 을 검증하였다.