• Journal of Intelligence and Information Systems
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• v.15 no.4
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• pp.183-200
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• 2009

Collaborative Filtering is one of the most used recommender systems. However, basically it cannot be used to recommend new products to customers because it finds products only based on the purchasing history of each customer. In order to cope with this shortcoming, many researchers have proposed the hybrid recommender system, which is a combination of collaborative filtering and content-based filtering. Content-based filtering recommends the products whose attributes are similar to those of the products that the target customers prefer. However, the hybrid method is used only for the limited categories of products such as music and movie, which are the products whose attributes are easily extracted. Therefore it is essential to find a more effective approach to recommend to customers new products in any category. In this study, we propose a new recommendation method which applies centrality concept widely used to analyze the relational and structural characteristics in social network analysis. The new products are recommended to the customers who are highly likely to buy the products, based on the analysis of the relationships among products by using centrality. The recommendation process consists of following four steps; purchase similarity analysis, product network construction, centrality analysis, and new product recommendation. In order to evaluate the performance of this proposed method, sales data from H department store, one of the well.known department stores in Korea, is used.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.5
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• pp.1269-1276
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• 2015

The mission capability of tank depends on its survivability. The survivability is ability for protection and tolerance by damage from threats. To improve the survivability of tank, we need an effectiveness analysis for loss of components, and accomplish performance enhancement using the result of analysis. In this paper, we develop a survivability analysis system for tank based on the importance. The importance numerically represents weight of each component which consisting of whole tank, also the importance is basic method of quantitative survivability analysis. To do this, we assign weight values to each component of tank, compose a weight tree, apply the importance calculation equation, and analyze the survivability of tank. Also we develop the system that consists of component structuralization and weight value setting program and survivability analysis and visualization program, and evaluate the system using implemented 3D CAD models of components of tank. The developed system apply to arrangement components.

• Journal of Korea Multimedia Society
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• v.8 no.11
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• pp.1449-1461
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• 2005

In this paper, we propose a vehicle recognition system based on the classification of vehicle identification mark and recognition of vehicle license plate. In the proposed algorithm, From the input vehicle image, we first simulate preprocessing procedures such as noise reduction, thinning etc., and detect vehicle identification mark and license plate region using the frequency distribution of intensity variation. And then, we classify extracted vehicle candidate region into identification mark, character and number of vehicle by using structural feature informations of vehicle. Lastly, we recognize vehicle informations with recognition of identification mark, character and number of vehicle using hybrid and vertical/horizontal pattern vector method. In the proposed algorithm, we used three properties of vehicle informations such as Independency property, discriminance property and frequency distribution of intensity variation property. In the vehicle images, identification mark is generally independent of the types of vehicle and vehicle identification mark. And also, the license plate region between character and background as well as horizontal/vertical intensity variations are more noticeable than other regions. To show the efficiency of the propofed algorithm, we tested it on 350 vehicle images and found that the propofed method shows good Performance regardless of irregular environment conditions as well as noise, size, and location of vehicles.

• Journal of Korea Multimedia Society
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• v.3 no.5
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• pp.479-494
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• 2000

Although the proliferation of real-time multimedia services over the Internet might indicate its successfulness in dealing with heterogeneous environments, it is obvious, on the other hand, that the internet now has to cope with a flood of multimedia data which consumes most of network communication channels due to a great deal of video or audio streams. Therefore, for the purpose of an efficient and appropriate utilization of network resources, it requires to develop and deploy a new scalable transmission technique n consideration of respective network environment and individual clients computing power. Also, we can eliminate the waste effects of storage device and data transmission overhead in that the same video stream duplicated according to QoS. The purpose of this paper is to develop a technology that can adjust the amount of data transmitted as an MPEG video stream according to its given communication bandwidth, and technique that can reflect dynamic bandwidth while playing a video stream. For this purpose, we introduce a media scalable media decomposer working on server side, and a scalable media composer working o n a client side, and then propose a scalable transmission method and a media sender and a media receiver in consideration of dynamic QoS. Those methods proposed her can facilitate an effective use of network resources, and provide multimedia MPEG video services in real-time with respect to individual client computing environment.

• International Journal of Highway Engineering
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• v.13 no.4
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• pp.81-91
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• 2011

This study was conducted to evaluate the necessity of the anchor lug system in continuously reinforced concrete pavement(CRCP) by comparing longitudinal displacements of CRCPs with and without anchor lugs, and to investigate the effect of horizontal cracking on CRCP performance by measuring the vertical displacements. The measurements before and after the anchor lug section was separated were conducted for 12 days in June, and for 14 days in August after the abrupt displacements according to cutting disappeared, respectively. This short term measurement results showed that when anchor lugs were installed, a daily displacement variation at any location was less than 0.1mm; therefore, longitudinal movements were negligibly small. When there were no anchor lugs, longitudinal displacements mainly occurred near the free end and the displacement variation was small; therefore, an expansion joint system seems to be employed at a CRCP terminus without installing anchor lugs. However, further studies are needed to verify the terminus behavior due to annual temperature changes. The horizontal crack width variation was ignorable and did not affect the vertical displacement of the slab. Therefore, the horizontal crack did not delaminate the slab and did not seem to reduce the structural capacity and performance of CRCP.

• Journal of Korean Society of Steel Construction
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• v.29 no.1
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• pp.81-88
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• 2017

Residual stress is defined as stress that already exists on a structural member from the effects of welding and plastic deformation before the application of loading. Due to such residual stress, welded H-section compression members under centroidal compression load can undergo buckling and failure for strength values smaller than the predicted buckling load and specified compressive strength. Therefore, this study was carried out to evaluate the effect of residual stress from welding on the determination of the buckling load and specified compressive strength of the H-section compression member according to the column length variation. A three-dimensional nonlinear finite element analysis was performed for the H-section compression member where the welded joint was fillet welded by applying heat inputs of 3.1kJ/mm and 3.6kJ/mm using the SAW welding method.

• Journal of the Korea Society of Computer and Information
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• v.17 no.1
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• pp.1-10
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• 2012

Improving operating frequency of processors is no longer today's issues; a multiprocessor technique which integrates many processors has received increasing attention. Currently, high-performance processors that integrate 64 or 128 cores are developing for large data processing over 2, 4, or 8 processor cores. This paper proposes an optimal many-core processor for synthesizing guitar sounds. Unlike the previous research in which a processing element (PE) was assigned to support one of guitar strings, this paper evaluates the impacts of mapping different numbers of PEs to one guitar string in terms of performance and both area and energy efficiencies using architectural and workload simulations. Experimental results show that the maximum area energy efficiencies were achieved at PEs=24 and 96, respectively, for synthesizing guitar sounds with sampling rate of 44.1kHz and 16-bit quantization. The synthesized sounds were very similar to original guitar sounds in their spectra. In addition, the proposed many-core processor was 1,235 and 22 times better than TI TMS320C6416 in area and energy efficiencies, respectively.

• Journal of the Korea Society of Computer and Information
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• v.10 no.5 s.37
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• pp.123-132
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• 2005

In this Paper, we present an improvement of switch node for wavelength multiplex optical network. Currently because of quick increase of internet traffic a big network capacity is demanded. Wavelength multiplex optical network Provides the data transfer of high speed and the transparent characteristic of the data. Therefore optic network configuration is the most powerful technology in the future. It will be able to control the massive traffic from the optical network in order to transmit the multimedia information of very many quantify. Consequently the node where the traffic control is Possible, is demanded. The optical switch node which manages efficiently the multiple wavelength was Proposed. This switch is composed of a optical switch module for switching and a wavelength converter module for wavelength conversion. It will be able to compose the switch fabric without optical/electro or electro/optical conversion using optical MEMS(Micro Electro Mechanical Switches) module. Finally, we present the good test result regarding the operational qualify of the switch fabric and the performance of optical signal from the switch node. The proposed switch node of the optic network will be able to control the massive traffic with all optical.

• Journal of the Korea Society of Computer and Information
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• v.11 no.6 s.44
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• pp.69-78
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• 2006

In the field of the bioinformatics, it plays an important role in predicting functional information or structure information to search similar sequence in biological DB. Biolrgical sequences have been increased dramatically since Human Genome Project. At this point, because the searching speed for the similar sequence is highly regarded as the important factor for predicting function or structure, the SMP(Sysmmetric Multi-Processors) computer or cluster is being used in order to improve the performance of searching time. As the method to improve the searching time of BLAST(Basic Local Alighment Search Tool) being used for the similarity sequence search, We suggest the nBLAST algorithm performing on the cluster environment in this paper. As the nBLAST uses the MPI(Message Passing Interface), the parallel library without modifying the existing BLAST source code, to distribute the query to each node and make it performed in parallel, it is possible to easily make BLAST parallel without complicated procedures such as the configuration. In addition, with the experiment performing the nBLAST in the 28 nodes of LINUX cluster, the enhanced performance according to the increase in the number of the nodes has been confirmed.

• Journal of the Korea Concrete Institute
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• v.19 no.2
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• pp.179-188
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• 2007

Recently, the concern on the receipt of poor ready-mixed concrete in the construction field and the durability of concrete has been increased. Based on the such background, a large number of measuring methods of water content for fresh concrete have been developed and enforced in a developed country. In this study, to investigate practicality for quality control of ready-mixed concrete among various water content measurement techniques, microwave range method, air meter method and capacitance measurement method as measuring methods of water content were selected. Then, it was evaluated estimating performance of water content according to the change of binder types, fine aggregate types, absorption ratio, water content and water-binder ratio in series I and II. Also, it was examined influence on error occurrence of water content according to change of properties of used materials in series III. Finally, based on this study, it was proposed fundamental data to utilize measurement technique of water content to quality control of ready-mixed concrete in construction field.