• Journal of KIISE:Computing Practices and Letters
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• v.10 no.1
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• pp.99-113
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• 2004

A new architecture called SAN(Storage Area Network) was developed in response to the requirements of high availability of data, scalable growth, and system performance. In order to use SAN more efficiently, most of SAN operating softwares support storage virtualization concepts that allow users to view physical storage devices attached to SAN as a large volume virtually h logical volume manager plays a key role in storage virtualization. It realizes the storage virtualization by mapping logical addresses to physical addresses. A logical volume manager also supports a snapshot that preserves a volume image at certain time and on-line reorganization to allow users to add/remove storage devices to/from SAN even while the system is running. To support the snapshot and the on-line reorganization, most logical volume managers have used table based mapping methods. However, it is very difficult to manage mapping table because the mapping table is large in proportion to a storage capacity. In this paper, we design and implement an efficient and flexible hybrid mapping method based on mathematical equations. The mapping method in this paper supports a snapshot and on-line reorganization. The proposed snapshot and on-line reorganization are performed on the reserved area which is separated from data area of a volume. Due to this strategy normal I/O operations are not affected by snapshot and reorganization. Finally, we show the superiority of our proposed mapping method through various experiments.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.726-734
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• 2015

Relational databases used by structuralizing data are the most widely used in data management at present. However, in relational databases, service becomes slower as the amount of data increases because of constraints in the reading and writing operations to save or query data. Furthermore, when a new task is added, the database grows and, consequently, requires additional infrastructure, such as parallel configuration of hardware, CPU, memory, and network, to support smooth operation. In this paper, in order to improve the web information services that are slowing down due to increase of data in the relational databases, we implemented a model to extract a large amount of data quickly and safely for users by processing Hadoop Distributed File System (HDFS) files after sending data to HDFSs and unifying and reconstructing the data. We implemented our model in a Web-based civil affairs system that stores image files, which is irregular data processing. Our proposed system's data processing was found to be 0.4 sec faster than that of a relational database system. Thus, we found that it is possible to support Web information services with a Hadoop-based big data processing technique in order to process a large amount of data, as in conventional relational databases. Furthermore, since Hadoop is open source, our model has the advantage of reducing software costs. The proposed system is expected to be used as a model for Web services that provide fast information processing for organizations that require efficient processing of big data because of the increase in the size of conventional relational databases.

• Journal of Broadcast Engineering
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• v.23 no.5
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• pp.682-692
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• 2018

In this paper, we propose an ARQ packet error control scheme using multiple threads in delivering massive capacity of multimedia based on MMT(MPEG Media Transport) protocol. On the sending side, each frame that constitutes an image is packetized into MMT packets based on MMT protocol. The header of the packet stores the sequence number of the frames contained in the packet and the time of presentation information. The payload of the packet stores the direct information that comprises the frame. The generated MMT packet is transmitted to the IP network. The receiving side checks if any error has occurred in the received packet. For any identified error, it controls the error through ARQ error control scheme and reconfigure the frame according to the information stored in the header of the received packet. At this point, a multi-threading based transport design is constructed so that each thread takes over a single frame, which increases the transmission efficiency of massive capacity multimedia. The efficiency of the multi-threading transport method is verified by solving the problems that might arise when using a single-thread approach if packets with errors are retransmitted.

• Journal of the Korean Society of Costume
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• v.18
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• pp.321-337
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• 1992

Fashions are constantly subject to change, so that forecasting trends in fashion is very difficult and the forecasting is very important. The reason is that forecasting is identifying a hot trend for the next days' business and projecting the future. The purpose of this study is to suggest the realistic forecasting theory identify fashion trends at present, further forecast fashion trends to 1995. For this study, historical models (th historical resurrection model, the historical continuity model) and the art movement model among the behavioral science models which was suggested in 1986 by Geoge B.Sproles were selected. According to this study, was exhibited. This curve was resulted from relation between 1980s fashion trends and the behavioral science models of fashion. Fashion trends to 1995 through will be followings; 1. Body Conscious look as one of the characteristics of modern fashion will bi continued throughout 1990s' fashion trends. 2. The attraction of Mini style was started from the middle of 1980s, recently gets near micro mini and super shouts, These are representative of the historical continuity model. 3. Mini look as revivals of '60s in early 1990s fashion trends. This phenomenon identifies that "Fashion is repetition" 4. When Mini look and super shorts reach, will not progress any more. In this time, will bi seen transfer of style be using classic style. Tat is modern classic will be appeared. also this condition is same from late 1960s to early 1970s. In view of the historical base, the action of the varieted pants will be prominent. 5. Fashion trends which passed through this process will transfer from young look to elegant look. In this time, designers will retrospect '30s and '50s fashion trends, and then will design modern feminine look. 6. Ethnic look, the fashion trend after that condition will be accelated feminine look. This look with the feminine look will reveal rich, colorful, elegance feminine image. 7. In 1980s, activity and function in clothes were demanded. The clothes which are considered these condition will be demanded continuously. 8. The variety of fashion will appear as mixmode and new coordinate look in a clothes simultaneously in fashion of '90s. And these looks will creat mixed beauty. 9. Pop art, op art, graphic art will be not only development of textile but also movement of fashion soul in 1990s. The fashion behavior will be continuously scientificated.

• Progress in Medical Physics
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• v.23 no.3
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• pp.162-168
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• 2012

In proton therapy, in vivo dose verification is one of the most important parts to fully utilize characteristics of proton dose distribution concentrating high dose with steep gradient and guarantee the patient safety. Currently, in order to image the proton dose distribution, a prompt gamma distribution detection system, which consists of an array of multiple CsI(Tl) scintillation detectors in the vertical direction, a collimator, and a multi-channel DAQ system is under development. In the present study, the optimal design of prompt gamma distribution detection system was studied by Monte Carlo simulations using the MCNPX code. For effective measurement of high-energy prompt gammas with enough imaging resolution, the dimensions of the CsI(Tl) scintillator was determined to be $6{\times}6{\times}50mm^3$. In order to maximize the detection efficiency for prompt gammas while minimizing the contribution of background gammas generated by neutron captures, the hole size and the length of the collimator were optimized as $6{\times}6mm^2$ and 150 mm, respectively. Finally, the performance of the detection system optimized in the present study was predicted by Monte Carlo simulations for a 150 MeV proton beam. Our result shows that the detection system in the optimal dimensions can effectively measure the 2D prompt gamma distribution and determine the beam range within 1 mm errors for 150 MeV proton beam.

• Journal of Korean Society of Transportation
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• v.34 no.3
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• pp.207-221
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• 2016

In Korea, older pedestrian accounted for 57% of all pedestrian deaths although a ratio of older pedestrian accidents to total pedestrian accidents was only 25.9%. Though ageing population problem becomes more challenging for road safety, little is know about the behaviour of older pedestrian's behaviour. This study aimed to identify road crossing behaviour of older pedestrian at three-lane unsignalized crosswalks using video image analysis and to compare the behaviour of older pedestrian to younger one by indicators including approaching speed, the number of walking steps and other factors. The results showed that there was a difference of approaching time at kerb, waiting time at kerb, the number of glances at kerb, and the number of glances at crossing between two groups under the situation of car approaching to crosswalks. It also showed that older pedestrian usually spent 1.16 times more than younger pedestrian to walk across the crosswalk with only 84.4% of walking speed of younger pedestrian. The number of steps of older pedestrian for road crossing was 1.12 times higher with 90% shorter steps than younger pedestrian. It was concluded that older pedestrian usually decided to walk across in case of 1.67 times longer headway than younger pedestrian's decision. These results could be applied in road and facility design for better safety of older pedestrians.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.12 s.159
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• pp.1737-1746
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• 2006

The purpose of this study is to present a concrete image of the ideal beauty as shown in era preceding 1945 that effects the shaping of our aesthetic values; by analyzing its characteristics through the covers of women's magazines of that period, this research aims to promote the understanding of beauty of the human body. The scope of my research extends throughout the collection of women's magazines stored in the National Library and the Korea Magazine Information Center. The gathered research materials are: 5 kinds of Shin-Yeo-Sung (신여성), 51 kinds Yeo-Sung(여성) and 30 kinds of Ga-Jung-Ji-Woo(가정지우). The result of the research could be summarized as the followings. Before the 1920's in response to the violent opening, there was a trend of sticking to the traditional standard. In the 1920's, the prevalent images of women were meek and fragile. Japanese standard of beauty was explicitly indicated. In the 1930s, as Western movies started to be shown to the general public, western features were idealized and furthermore intelligence was required as a further condition. In the 1940s, preparation of the war led to encouragement of images of motherhood and natural beauty, and resistant to this trend led to pseudoclassicism.

• Cartoon and Animation Studies
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• s.14
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• pp.165-176
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• 2008

In the future there would be many kinds of digital images for many industrial markets. 3D stereoscopic images for variable fields; medical operation, film and animation, broadcasting, internet, game, or design for art and architecture. And many people to work about computer programming, and digital image making will concern about it more and more. However, these kinds works and studies are focused on the professional technical fields like 3D display or computer programming technology so far. To revitalize the market of a variable stereoscopic contents, there should build up the foundation for easy processing of the making stereoscopic images. This paper is based on stereoscopic making skills for anaglyph system. An anaglyph system has an old history about making stereoscopic images, and very simple method to produce the stereoscopic images. Particularly this study is focused on color compositing technique, and camera positioning on the compositing system. It will help optimization of the environments to create 3D motion graphic and animation contents.

• The Journal of Engineering Geology
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• v.27 no.4
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• pp.367-376
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• 2017

Recently, tunneling under the seabed is becoming increasingly common in many countries. In Korea, there are proposals to tunnel from the mainland to Jeju Island. Safe construction requires geologic structures such as faults to be characterized during the design and construction phase; however, unlike on land, such structures are difficult to survey seabed. This study aims to develop an algorithm that uses geostatistics to automatically derive large-scale geological structures on the seabed. The most important considerations in this method are the optimal size of the moving window, the optimal type of spatial statistics, and determination of the optimal percentile standard. Finally, the optimal analysis algorithm was developed using the R program, which comprehensibly presents variations in spatial statistics. The program allows the type and percentile standard of spatial statistics to be specified by the user, thus enabling an analysis of the geological structure according to variations in spatial statistics. The geotechnical defense-training algorithm shows that a large, linear geological lineament is best visualized using a $3{\times}3$ moving window and a 10% upper standard based on the moving variance value and fractile. In particular, setting the fractile criterion to the upper 0.5% almost entirely eliminates the error values from the contour image.

• Journal of Biomedical Engineering Research
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• v.28 no.3
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• pp.397-409
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• 2007

Owing to needs of biomechanical comprehension and analysis to obtain various medical treatment designs which are related with the spine in order to cure and diagnose LBP patients, the FE modeling and nonlinear analysis of lumbosacrum including a partial ilium and iliolumbar ligaments, were carried out. First, we investigated whether the geometrical configuration of vertebrae displayed by DICOM slice files is regular and normal condition. After constructing spinal vertebrae including a partial ilium, a sacrum and five lumbars (from L1 to L5)with anatomical shape reconstructed using softwares such as image modeler and CAD modeler, we added iliolumbar ligaments, lumbar ligaments, discs and facet joints, etc.. And also, we assigned material property and discretized the model using proper finite element types, thus it was completely modeled through the above procedure. For the verification of each segment, average sagittal ROM, average coronal ROM and average transversal ROM under various loading conditions(${\pm}10Nm$), average vertical displacement under compression(400N), ALL(Anterior Longitudinal Ligament) and PLL(Posterior Longitudinal Ligament) force at L12 level, strains of seven ligaments on sagittal plane at L45 level and maximal strain of disc fibers according to various loading conditions at L45 level, etc., they were compared with experimental results. For the verification of multilevel-lumbosacrum spine including partial ilium and iliolumbar ligaments, the cases with and without iliolumbar ligaments were compared with ROM of experiment. The results were obtained from analysis of the verified FE model as follows: I) Iliolumbar ligaments played a stabilizing role as mainly posterior iliolumbar ligaments under flexion and as both posterior and anterior iliolumbar ligaments of one side under lateral bending. 2) The iliolumbar ligaments decreased total ROM of 1-8% in total model according to various motion conditions, which changed facet contact forces of L5S level by approximately 0.8-1.4 times and disc forces of L5S level by approximately 0.8-1.5 times more than casewithout ilioligaments, under various loading conditions. 3) The force of lower discs such as L45 and L5S was bigger than upper discs under flexion, left and right bending and left and right twisting, except extension. 4) It was predicted that strains of posterior ligaments among iliolumbar ligaments would produce the maximum 16% under flexion and the maximum 10% under twisting. 5) It's expected that this present model applies to the development and design of artificial disc, since it was comparatively in agreement with the experimental datum.