• Journal of KIISE
• /
• v.41 no.11
• /
• pp.900-910
• /
• 2014

Multi-view video is obtained by capturing one three-dimensional scene with many cameras at different positions. The computational complexity of multi view video coding increases in proportion to the number of cameras. To reduce computational complexity and maintain the image quality, improved prediction structure and motion estimation method is proposed in this paper. The proposed prediction structure exploits an average distance between the current picture and its reference pictures. The proposed prediction structure divides every GOP into several groups to decide the maximum index of hierarchical B layer and the number of pictures of each B layer. And the proposed motion estimation method uses a hierarchical search strategy. This strategy method consists of modified diamond search pattern, progressive diamond search pattern and modified raster search pattern. Experiment results show that the complexity reduction of the proposed prediction structure and motion estimation method over JMVC (Joint Multiview Video Coding) reference model using hierarchical B pictures of Fraunhofer-HHI and TZ search method can be up to 40~70% while maintaining similar video quality and bit rates.

• The Journal of the Korea Contents Association
• /
• v.17 no.3
• /
• pp.329-336
• /
• 2017

In video compression, Motion Estimation(ME) limits the performance of image quality and generated bit rates. However, it requires much complexity in the encoder part. Multi-view video uses many cameras at different positions. Multi-view video coding needs huge computational complexity in proportion to the number of the cameras. To reduce computational complexity and maintain the image quality, an effective motion estimation method is proposed in this paper. The proposed method exploiting the characteristics of motion vector distribution and the motion of video. The proposed is a kind of a hierarchical search strategy. This strategy consists of multi-grid rhombus pattern, diagonal pattern, rectangle pattern, and refinement pattern. Experiment results show that the complexity reduction of the proposed method over TZ search method and PBS (Pel Block Search) on JMVC (Joint Multiview Video Coding) can be up to 40~75% and 98% respectively while maintaining similar video image quality and generated bit rates.

• Journal of Korean Library and Information Science Society
• /
• v.22
• /
• pp.139-169
• /
• 1995

The purpose of this study is to analyze the search pattern and search outcome of the National Central Library OPAC users by measuring their success rates and identifying the factors of failure and the personal background which bring about the differences of the search outcome. Various methods have been used for the study. Personal interview was used to find the pattern of the search, observation method was used to investigate the search process and the failure factors, and a questionnaire was used to survey personal background of searchers. The data were collected during the period of 7 days from April 17, 1995 through April 23, 1995. The search of 1, 217 cases, sampling systematically 25% out of the whole users, were collected and analyzed for the study. The findings of the study can be summarized as follows : First, in regard to the pattern, known-item search(72.6%) was preferred to the subject search(27.4%) and in case of known-item search the access point used were in the order of title, author, title and author. Second, the overall success rate of known-item search was 50.3% and the success rates were in order of author and date, title, and author. The failure factors of known-item search were divided into users factor of 67% and the database factor of 33%, respectively. Third, in case of subject search, its overall success rate was 44.1% and the keyword was the major access point, and the average of precision ratio was very low. Fourth, the analysis of the personal background related to the search outcome has shown significant differences by sex, the experience of using OPAC, education level, and the frequency of using other information retrieval systems. Based on the results the following suggestions can be made to improve the search outcome : First, the system should be su n.0, pplemented online help function to assist users to overcome the failure during search. Second, user instruction in group or individual should be implemented for the users to understand the system.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.9 no.5
• /
• pp.1218-1224
• /
• 2008

Located on the upstream of a gene, the promoter region that plays a very important role in the control of gene expression as a signal part has various binding sites for transcription factors. These binding sites are present in various parts of the promoter region and assume an aspect of highly conserved consensus sequence pattern. This paper deals with the introductions of search methods for consensus pattern, including Wataru method, EM algorithm, MEME algorithm, Genetic algorithm and Phylogenetic Footprinting method, and intends to give future prospects of research on this field.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.29 no.4D
• /
• pp.555-561
• /
• 2009

In lieu of section profile data, a fitting of the bored tunnel shape is more significant confirmation for maintenance of a tunnel. Before the permit on the completion of a tunnel, deformation of the completed tunnel with respect to the design model are considered. And deformation can be produced at continuously along the entire of the tunnel section. This study firstly includes an analysis of algebraic approach and test it with an observed field data. And then a number of methods, line search method, genetic algorithm, and pattern search methods, are compared with the 3D tunnel shape fitting. Algebraic methods can solve a simple circular cylinder type as like a railway tunnel. However, a more complex model (compound circular curve and non circular) as like a highway tunnel has to be solved with soft computing tools in the cause of conditional constraints. The genetic algorithm and pattern search methods are computationally more intensive, but they are more flexible at a complex condition. The line search method is fastest, but it needs a narrow bounds of the initial values.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.53 no.1
• /
• pp.22-31
• /
• 2004

This paper deals with the dynamic hand gesture recognition based on computer vision using neural networks. This paper proposes a global search method and a local search method to recognize the hand gesture. The global search recognizes a hand among the hand candidates through the entire image search, and the local search recognizes and tracks only the hand through the block search. Dynamic hand gesture recognition method is based on the skin-color and shape analysis with the invariant moment and direction information. Starting point and ending point of the dynamic hand gesture are obtained from hand shape. Experiments have been conducted for hand extraction, hand recognition and dynamic hand gesture recognition. Experimental results show the validity of the proposed method.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.11 no.11
• /
• pp.5671-5693
• /
• 2017

With the rapid development of cloud computing, more and more data owners are motivated to outsource their data to cloud for various benefits. Due to serious privacy concerns, sensitive data should be encrypted before being outsourced to the cloud. However, this results that effective data utilization becomes a very challenging task, such as keyword search over ciphertexts. Although many searchable encryption methods have been proposed, they only support exact keyword search. Thus, misspelled keywords in the query will result in wrong or no matching. Very recently, a few methods extends the search capability to fuzzy keyword search. Some of them may result in inaccurate search results. The other methods need very large indexes which inevitably lead to low search efficiency. Additionally, the above fuzzy keyword search methods do not support access control. In our paper, we propose a searchable encryption method which achieves fuzzy search and access control through algorithm design and Ciphertext-Policy Attribute-based Encryption (CP-ABE). In our method, the index is small and the search results are accurate. We present word pattern which can be used to balance the search efficiency and privacy. Finally, we conduct extensive experiments and analyze the security of the proposed method.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1994.10a
• /
• pp.267-272
• /
• 1994

This work presents a method of optimum design for reinforced concrete building frames with rectangular cross sections. The optimization techniques used is based on the principle of divided parameters. The design variable parameters are divided into two groups, external and internal, and the optimization is also divided into external and internal procedure. This principle overcomes difficulties arising from the presence of two materials in one element, the property peculiar to reinforced concrete. Several search algorithms are tested to verify their accuracy for the external optimization. Among them pattern search algorithms has been found consistent. This work proposes a new method, modified pattern search, and a number of sample problems prove its accuracy and usefulness. Exhaustive search for all local minima in the design spaces for two sample problems has been carried out to understand the nature of the problem. The number of local minima identified is quite more than expected and it has become understood that the researcher's task in this field is to find a better local minimum if not global. The designs produced by the method preposed have been found better than those from other method, and they are in full accord with ACI Building Code Requirments(ACI 318-89).

• Proceedings of the KIEE Conference
• /
• 2004.11d
• /
• pp.106-109
• /
• 2004

축구 전용 경기장에서 캐노피에 설치되는 등기구의 위치를 Pattern Search법을 이용 컴퓨터 시뮬레이션하여 조명 등기구 배치간격을 변화시킴으로 국 내외 (FIFA, 유럽방송연맹, KS) 기준에 명시된 수평면 조도, 수직면 조도, 균제도, 눈부심 정도에 적합한 최적의 값을 찾아내어 향후 국내 축구 전용 경기장 조명기구의 설계 및 시공, 유지관리 보수시 많은 참고가 되었으면 한다.

• KIPS Transactions on Software and Data Engineering
• /
• v.7 no.8
• /
• pp.281-286
• /
• 2018

With recent increase in complexity and variety of information and massively available information, interest in and necessity of ontology has been on the rise as a method of extracting a meaningful search result from massive data. Although there have been proposed many methods of extracting the ontology from a given text of a natural language, the extraction based on most of the current methods is not consistent with the structure of the ontology. In this paper, we propose a method of automatically creating ontology by distinguishing a term needed for establishing the ontology from a text given in a specific domain and extracting various relationships between the terms based on the pattern-based method. To extract the relationship between the terms, there is proposed a method of reducing the size of a searching space by taking a matching set of patterns into account and connecting a join-set concept and a pattern array. The result is that this method reduces the size of the search space by 50-95% without removing any useful patterns from the search space.