• Journal of Electrical Engineering and information Science
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• 제2권5호
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• pp.72-78
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• 1997

This paper presents a fuzzy relaxation algorithm, which is based on the possibility and FAM instead of he probability and compatibility coefficients used in most of existing probabilistic relaxation algorithms, Because of eliminating stages for estimating of compatibility coefficients and normalization of the probability estimates, the proposed fuzzy relaxation algorithms increases the parallelism and has a simple iteration scheme. The construction of fuzzy relaxation scheme consists of the following three tasks: (1) definition of in/output linguistic variables, their term sets, and possibility. (2) Definition of FAM rule bases for relaxation using fuzzy compound relations. (3) Construction of the iteration scheme for calculating the new possibility estimate. Applications to region segmentation an ege detectiojn algorithms show that he proposed method can be used for not only reducing the image ambiguity and segmentation errors, but also enhancing the raw edge iteratively.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제4권5호
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• pp.968-988
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• 2010

Anonymous hierarchical identity based encryption (HIBE) is an extension of identity based encryption (IBE) that can use an arbitrary string like an e-mail address for a public key, and it additionally provide the anonymity of identity in ciphertexts. Using the anonymous HIBE schemes, it is possible to construct anonymous communication systems and public key encryption with keyword search. This paper presents an anonymous HIBE scheme with constant size ciphertexts under prime order symmetric bilinear groups, and shows that it is secure under the selective security model. Previous anonymous HIBE schemes were constructed to have linear size ciphertexts, to use composite order bilinear groups, or to use asymmetric bilinear groups that is a special type of bilinear groups. Our construction is the first efficient anonymous HIBE scheme that has constant size ciphertexts and that uses prime order symmetric bilinear groups. Compared to the previous scheme of composite order bilinear groups, ours is ten times faster. To achieve our construction, we first devise a novel cancelable random blinding technique. The random blinding property of our technique provides the anonymity of our construction, and the cancellation property of our technique enables decryption.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권8호
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• pp.2027-2041
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• 2013

In this paper, we propose a novel reversible data hiding scheme in the index tables of the vector quantization (VQ) compressed images based on index set construction strategy. On the sender side, three index sets are constructed, in which the first set and the second set include the indices with greater and less occurrence numbers in the given VQ index table, respectively. The index values in the index table belonging to the second set are added with prefixes from the third set to eliminate the collision with the two derived mapping sets of the first set, and this operation of adding prefixes has data hiding capability additionally. The main data embedding procedure can be achieved easily by mapping the index values in the first set to the corresponding values in the two derived mapping sets. The same three index sets reconstructed on the receiver side ensure the correctness of secret data extraction and the lossless recovery of index table. Experimental results demonstrate the effectiveness of the proposed scheme.

• 대한수학회지
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• 제51권1호
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• pp.163-187
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• 2014

We present a multi-stage Roe-type numerical scheme for a model of two-phase flows arisen from the modeling of deflagration-to-detonation transition in granular materials. The first stage in the construction of the scheme computes the volume fraction at every time step. The second stage deals with the nonconservative terms in the governing equations which produces states on both side of the contact wave at each node. In the third stage, a Roe matrix for the two-phase is used to apply on the states obtained from the second stage. This scheme is shown to capture stationary waves and preserves the positivity of the volume fractions. Finally, we present numerical tests which all indicate that the proposed scheme can give very good approximations to the exact solution.

• 한국기록관리학회지
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• 제17권1호
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• pp.117-141
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• 2017

시소러스는 분류체계의 분류명을 제어해 주고, 분류표의 색인 역할을 수행할 수 있다. 기록관리에 있어서 시소러스는 기능어를 제어하고, 검색의 접근점을 확장시켜 기능분류체계를 보완해 준다. 그런데 최근에는 정보환경의 변화와 시소러스 구축 및 활용 시스템의 발전으로 시소러스 구축에 관한 국제표준인 ISO 25964가 개정되었다. 또한 기록관리 전반에 대한 국제표준인 ISO 15489의 제1부도 2016년에 개정되었다. 또한 영국의 IPSV나 유럽의 EuroVoc, 뉴질랜드의 FONZ 등은 최근의 경향을 반영하여 효과적으로 시소러스를 구축하고 연계하고 있었다. 이에 본 연구에서는 체계적인 기록관리를 위한 시소러스 구축지침을 관련 표준과 사례 측면에서 살펴보고, 현재의 우리나라 기록관리 분야 시소러스 구축지침의 개선 방안을 제안하였다.

• 한국측량학회지
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• 제37권2호
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• pp.45-53
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• 2019

RGB-D SLAM (Simultaneous Localization and Mapping) refers to the technology of using deep camera as a visual sensor for SLAM. In view of the disadvantages of high cost and indefinite scale in the construction of maps for laser sensors and traditional single and binocular cameras, a method for creating three-dimensional map of indoor environment with deep environment data combined with RGB-D SLAM scheme is studied. The method uses a mobile robot system equipped with a consumer-grade RGB-D sensor (Kinect) to acquire depth data, and then creates indoor three-dimensional point cloud maps in real time through key technologies such as positioning point generation, closed-loop detection, and map construction. The actual field experiment results show that the average error of the point cloud map created by the algorithm is 0.0045m, which ensures the stability of the construction using deep data and can accurately create real-time three-dimensional maps of indoor unknown environment.

• 한국환경과학회지
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• 제22권5호
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• pp.523-531
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• 2013

In this study, a method of simulating ephemeral stream runoff characteristics in Jeju watershed is newly suggested. The process based conceptual-physical scheme is established based on the SWAT-K and applied to Cheonmi-cheon watershed which shows the typical pattern of ephemeral stream runoff characteristics. For the proper simulation of this runoff, the intermediate flow and baseflow are controlled to make downward percolation should be dominant. The result showed that surface runoff simulated by using the modified scheme showed good agreement with observed runoff data. In addition, it was found that the estimated runoff directly affected the groundwater recharge rate. This conceptual model should be continuously progressed including rainfall interception, spatially estimated evapotranspiration and so forth for the reasonable simulation of the hydrologic characteristics in Jeju island.

• 정보처리학회논문지C
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• 제12C권6호
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• pp.907-916
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• 2005

응용 계층 멀티캐스트 프로토콜인 RMCP는 2003년 12월에 ITU-T와 ISO의 멀티캐스트 통신 분과 합동 국제 표준 회의에서 표준안으로 결정되었으며 표준에서는 멀티캐스트 트리를 정적으로 구성하는 방식을 제안하였다. 본 논문에서 제안하는 기법은 기존의 RMCP 표준에서 제안하는 Static Tree 방식보다 초기 지연 시간 및 사용자 요구 QoS 측면에서 더 나은 성능을 보이며 동적으로 멀티캐스트 트리를 구성할 수 있는 새로운 QoS 기반 트리 기법을 제안한다 본 논문에서 제안하는 QoS 기반 트리 기법은 사용자 요구 QoS를 만족할 수 있는 복수 개의 서브넷 그룹을 이용하는 Best-Fit 방법과 최대 전송 대역폭을 가지는 서브넷 그룹을 이용하는 First-Fit 방법으로 구성된다. 본 논문에서 제안하는 두가지 방법은 기존의 Static 방법보다 우수한 성능을 보였다.

• 한국건설관리학회논문집
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• 제17권1호
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• pp.110-118
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• 2016

최근 국내 건설 산업은 높은 경제성장률과 신기술 도입 등으로 인하여 대형화, 초고층화, 첨단화가 되어가고 있으며, 건설 품질에 대한 사용자의 관심과 요구 수준은 더욱 높아지고 있다. 이는 과거의 양적인 성장위주에서 벗어나 시장변화에 능동적으로 대처할 수 있는 한층 더 체계적이고 수준 높은 품질관리의 필요성이 요구된다고 할 수 있다. 정부는 이러한 시대적 요구사항을 반영하여 건설공사의 시공 및 사용재료에 대한 적정성 여부와 부실시공 방지 등 품질확보를 위한 점검을 강화하고 있다. 그러나 이와 같은 점검 강화에도 불구하고 품질관리에 대한 인식 부족 및 형식적인 품질관리 운영 등으로 인하여 많은 문제점이 발생되고 있으며, 품질관리 점검 시 반복적이고 지속적으로 지적사항이 발생되고 있다. 따라서 본 연구에서는 반복적인 지적사항을 줄이고, 부적절한 품질관리와 부실시공을 방지하기 위해 서울시 품질시험소에서 2012년 3월부터 2014년 10월까지 393개 건설현장의 품질관리 적정성 확인 점검을 통해 도출한 지적사항 3,443건을 심층 분석하여 실효성 있는 현장 품질관리 개선방안을 제시하고자 한다. 본 연구에서 제안한 현장 품질관리의 개선방안을 통해 부적절한 품질관리와 부실시공의 방지, 반복적이고 지속적으로 나타나는 지적사항의 감소, 현장의 품질관리 업무향상과 같은 개선효과가 있을 것으로 기대된다.

• Water Engineering Research
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• 제1권1호
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• pp.63-74
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• 2000

This paper presents a two- phase search scheme for optimal pipe expansion of expansion of existing water distribution systems. In pipe network problems, link flows affect the total cost of the system because the link flows are not uniquely determined for various pipe diameters. The two-phase search scheme based on stochastic optimization scheme is suggested to determine the optimal link flows which make the optimal design of existing pipe network. A sample pipe network is employed to test the proposed method. Once the best tree network is obtained, the link flows are perturbed to find a near global optimum over the whole feasible region. It should be noted that in the perturbation stage the loop flows obtained form the sample existing network are employed as the initial loop flows of the proposed method. It has been also found that the relationship of cost-hydraulic gradient for pipe expansion of existing network affects the total cost of the sample network. The results show that the proposed method can yield a lower cost design than the conventional design method and that the proposed method can be efficiently used to design the pipe expansion of existing water distribution systems.