• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.6
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• pp.445-452
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• 2019

In this study, parallel processing codes of k-means clustering algorithm were developed and implemented in a PC-cluster for unsupervised classification of large satellite images. We implemented intra-node code using multicores of CPU (Central Processing Unit) based on OpenMP (Open Multi-Processing), inter-nodes code using a PC-cluster based on message passing interface, and hybrid code using both. The PC-cluster consists of one master node and eight slave nodes, and each node is equipped with eight multicores. Two operating systems, Microsoft Windows and Canonical Ubuntu, were installed in the PC-cluster in turn and tested to compare parallel processing performance. Two multispectral satellite images were tested, which are a medium-capacity LANDSAT 8 OLI (Operational Land Imager) image and a high-capacity Sentinel 2A image. To evaluate the performance of parallel processing, speedup and efficiency were measured. Overall, the speedup was over N / 2 and the efficiency was over 0.5. From the comparison of the two operating systems, the Ubuntu system showed two to three times faster performance. To confirm that the results of the sequential and parallel processing coincide with the other, the center value of each band and the number of classified pixels were compared, and result images were examined by pixel to pixel comparison. It was found that care should be taken to avoid false sharing of OpenMP in intra-node implementation. To process large satellite images in a PC-cluster, code and hardware should be designed to reduce performance degradation caused by file I / O. Also, it was found that performance can differ depending on the operating system installed in a PC-cluster.

• Journal of Digital Convergence
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• v.13 no.2
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• pp.73-81
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• 2015

SNS is in the process of fast evolution as well. This study is about influence of authenticity and interactivity among Facebook Fan Page users. Authenticity is something people form in the process of expressing and sharing information thru SNS Facebook Fan Page. Interactivity is a level of participation of users in the process of expressing and sharing information thru SNS Facebook Fan Page. The focus of this paper is to see the power of authenticity and interactivity of SNS Facebook Fan Page users in a time of crisis. Authenticity is proven as a valuable asset for corporations for it showed a sturdy characteristic even when something terrible happened. When a crisis attacked, high authenticity user group was not willing to change their evaluation on a company reputation and image as much as low authenticity user group. Interestingly enough, the meaning interactivity level was strikingly different from what we expected. The more their level of interactivity, was the more they were likely to change their evaluation on a company in a time of crisis. A serious discussion is necessary for this contraty results.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.35 no.3
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• pp.187-194
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• 2017

The present study introduces a method to parallelize k-means clustering algorithm for fast unsupervised classification of large satellite imagery. Known as a representative algorithm for unsupervised classification, k-means clustering is usually applied to a preprocessing step before supervised classification, but can show the evident advantages of parallel processing due to its high computational intensity and less human intervention. Parallel processing codes are developed by using multi-threading based on OpenMP. In experiments, a PC of 8 multi-core integrated CPU is involved. A 7 band and 30m resolution image from LANDSAT 8 OLI and a 8 band and 10m resolution image from Sentinel-2A are tested. Parallel processing has shown 6 time faster speed than sequential processing when using 10 classes. To check the consistency of parallel and sequential processing, centers, numbers of classified pixels of classes, classified images are mutually compared, resulting in the same results. The present study is meaningful because it has proved that performance of large satellite processing can be significantly improved by using parallel processing. And it is also revealed that it easy to implement parallel processing by using multi-threading based on OpenMP but it should be carefully designed to control the occurrence of false sharing.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.328-328
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• 2007

Large area matrix-addressed image detectors are a recent technology for x-ray imaging with medical diagnostic and other applications. The imaging properties of x-ray pixel detectors depend on the quantum efficiency of x-rays, the generated signal of each x-ray photon and the distribution of the generated signal between pixels. In a phosphor coated detector the light signal is generated by electrons captured in the phosphor screen. In our study we simulated the lateral spread distributions for phosphor coupled detector by Monte Carlo simulations. Most simulations of such detectors simplify the setup by only taking the conversion layer into account neglecting behind. The Monte Carlo code MCNPX has been used to simulate the complete interaction and subsequent charge transport of x-ray radiation. This has allowed the analysis of charge sharing between pixel elements as an important limited factor of digital x-ray imaging system. The parameters are determined by lateral distribution of x-ray photons and x-ray induced electrons. The primary purpose of this study was to develop a design tool for the evaluation of geometry factor in the phosphor coupled optical imaging detector. In order to evaluate the spatial resolution for different phosphor material, phosphor geometry we have developed a simulation code. The developed code calculates the energy absorption and spatial distribution based on both the signal from the scintillating layer and the signal from direct detection of x-ray in the detector. We show that internal scattering contributes to the so-called spatial resolution drop of the image detector. Results from the simulation of spatial distribution in a phosphor pixel detector are presented. The spatial resolution can be increased by optimizing pixel size and phosphor thickness.

• Asia Marketing Journal
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• v.10 no.3
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• pp.103-125
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• 2008

After having changed its corporate brand from LG Fire & Marine Insurance to LIG Non-life Insurance in 2006, LIG Insurance has successfully built the corporate image as the leading insurance financial group by engaging in extensive corporate social responsibility activities. LIG, as 'a partner for sharing precious moments of life', intended to provide customers a new value of an insurance by building up the new corporate brand. It established three values to be shared internally. First was to instill a brand value orientation within the organization. Second, the firm identified the brand's value to be delivered to the customers. Third, they defined the image objective to be communicated to them. Based on these set of objectives, the company designed and implemented an integrated marketing communication(IMC) strategy over several years. The result was a successful transition to the new corporate brand name.

• Journal of Digital Contents Society
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• v.9 no.2
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• pp.245-250
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• 2008

Psychology of color is a research field of psychology for studying human's behavior connected with color. Color carries symbolism and image while sharing psychological consensus with human. Each color has a respective image such as hope, passion, love, life, death, and so on. Peculiar stimuli by colors on these images have great influence on human's emotion and psychology. We therefore proposed a method for understanding human's state of emotion based on colors in this paper. In order to understand human's state of emotion, we analyzed color information used to model a room by a user and then described frequencies of each color as percent using fuzzy inference rules by membership values of fuzzy membership functions for colors used for modeling the room. When we applied the proposed color-based emotion analysis method to emotional state based on colors of Alschuler and Hattwick, we could see the proposed method is efficient.

• Journal of radiological science and technology
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• v.30 no.1
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• pp.47-51
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• 2007

Development of hospital information system and Picture Archiving Communication System is not new in the medical field, and the development of internet and information technology are also universal. In the course of such development, however, it is hard to share medical information without a refined standard format. Especially in the department of radiology, the role of PACS has become very important in interchanging information with other disparate hospital information systems. A specific system needs to be developed that radiological reports are archived into a database efficiently. This includes sharing of medical images. A model is suggested in this study in which an internal system is developed where radiologists store necessary images and transmit them in the standard international clinical format, Clinical Document Architecture, and share the information with hospitals. CDA document generator was made to generate a new file format and separate the existing storage system from the new system. This was to ensure the access to required data in XML documents. The model presented in this study added a process where crucial images in reading are inserted in the CDA radiological report generator. Therefore, this study suggests a storage and transmission model for CDA documents, which is different from the existing DICOM SR. Radiological reports could be better shared, when the application function for inserting images and the analysis of standard clinical terms are completed.

• Journal of Internet Computing and Services
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• v.9 no.5
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• pp.47-58
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• 2008

Charts can propagate information more effectively by visualizing various types of information. Due to this reason, many web developers often use charts when they display information on the web. However, using a chart requires a special dedicated software to install and it is difficult to share the finished charts since they are usually in raster format. The raster format images are fixed in size, therefore, experience image distortion problem when their sizes are changed. In this paper, we propose a web-based chart generating system using CML(Chart Markup Language) to solve the current compatibility and sharing problems. The proposed chart generating system first analyzes XML, Text, or HTML documents to extract chart information in the documents, and then it converts collected chart information to CML. The converted CML documents are displayed on the web browser using a vector method. The vector method has an advantage of protecting its images from distortion even when image sizes are scaled. The CML, proposed in this paper, is a chart markup language based on XML for modeling charts Information. If CML is used for presenting a chart in a web, it makes easier to share and to convert the chart information.

• Korean Journal of Remote Sensing
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• v.28 no.1
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• pp.29-38
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• 2012

Nowadays, most remote sensing image processing systems are on client-based ones. But in the view of information technology, a web-based system is predominant, being closely related to cloud computing and services. The web-based system in remote sensing is somewhat limited in the area of data sharing or dissemination, but it is necessary to extend. This study is to implement a web-based system and its component modules for SAR data processing. First, the previous cases dealt with both web computing and SAR information are investigated. InSAR information processing and concerned modules for a web-based system among SAR research domains are the main points in this work. It is expected that this approach contributes to the first attempt to link web computing technology such as HTML5 and satellite image processing.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.5
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• pp.1-9
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• 2010

In this paper, the novel architecture of Intra-prediction & DCTQ hardware, which can process for the Full HD image($1980{\times}1088$@30fps) in realtime, is proposed. The cycle optimization method for the overall cycle of prediction, transform, scaling, descaling, and reconstruction is proposed. To reduce the cycle in the $4{\times}4$ prediction, the quantization process is performed during the prediction cycle and pre-selection of 2 modes among the 9 modes is performed to reduce the hardware area. To reduce the hardware of $16{\times}16$ and $8{\times}8$ prediction, the sharing logic between 2 prediction is utilized. The proposed architecture can process the 30frame/sec of full HD image in 108 MHz clock and operate 425 cycle for one macroblock.