• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.5
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• pp.1009-1019
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• 2017

Mobile Edge Computing(MEC) is a emerging technology to cope with mobile traffic explosion and to provide a variety of services having specific requirements by means of running some functions at mobile edge nodes directly. For instance, caching function can be executed in order to offload mobile traffics, and safety services using real time video analytics can be delivered to users. So far, a myriad of methods and architectures for personalized service recommendation have been proposed, but there is no study on the subject which takes unique characteristics of mobile edge computing into account. To provide personalized services, acquiring users' context is of great significance. If the conventional personalized service model, which is server-side oriented, is applied to the mobile edge computing scheme, it may cause context isolation and privacy issues more severely. There are some advantages at mobile edge node with respect to context acquisition. Another notable characteristic at MEC scheme is that interaction between users and applications is very dynamic due to temporal relation. This paper proposes the local service recommendation platform architecture which encompasses these characteristics, and also discusses the personalized service recommendation mechanism to be able to mitigate context isolation problem and privacy issues.

• Journal of KIISE:Computer Systems and Theory
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• v.37 no.3
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• pp.147-160
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• 2010

The system virtualization shows interest in the consolidation of servers for the efficient utilization of system resources. There are many various researches to utilize a server machine more efficiently through the system virtualization technique, and improve performance of the virtualization software. These researches have studied with the activity to control the resource allocation of virtual machines dynamically focused on CPU, or to manage resources in the cross-machine using the migration. However, the researches of the memory management have been wholly lacking. In this respect, the use of memory is limited to allocate the memory statically to virtual machine in server consolidation. Unfortunately, the static allocation of the memory causes a great quantity of the idle memory and decreases the memory utilization. The underutilization of the memory makes other side effects such as the load of other system resources or the performance degradation of services in virtual machines. In this paper, we suggest the dynamic allocation of the memory in Xen to control the memory allocation of virtual machines for the utilization without the performance degradation. Using AR model for the prediction of the memory usage and ACO (Ant Colony Optimization) algorithm for optimizing the memory utilization, the system operates more virtual machines without the performance degradation of servers. Accordingly, we have obtained 1.4 times better utilization than the static allocation.

• Journal of KIISE:Computer Systems and Theory
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• v.37 no.3
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• pp.184-193
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• 2010

This paper proposes a biological iridescence BRDF(Bidirectional Reflectance Distribution Function) compression and rendering method. In the graphics technology, iridescence sometimes is named structure colors. The main features of these symptoms are shown transform of color and brightness by varying viewpoint. Graphics technology to render this is the BRDF technology. The BRDF methods enable realistic representation of varying view direction, but it requires a lot of computing power because of large data. In this paper, we obtain reflection map from iridescence BRDF, analyze color of reflection map and propose representation method by several colorfully concentric circle. The one concentric circle represents beam width of reflection ray by one normal vector. In this paper, we synthesize rough concentric by using several virtually optical normal vectors. And we obtain spectrum information from concentric circles passing through the center point. The proposed method enables IBR(image based rendering) technique which results is realistic illuminance and spectrum distribution by one texture from reduced BRDF data within spectrum.

• Archives of design research
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• v.19 no.4 s.66
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• pp.71-80
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• 2006

Collaboration has become essential in the product design process due to internationalized and specialized business environments. This study presents a real-time collaborative 3D design workspace for distributed designers, focusing on the development and the evaluation of new interaction techniques supporting nonverbal communication such as awareness of participants, shared manipulation and tele-presence. Requirements were identified in terms of shared objects, shared workspaces and awareness through literature reviews and an observational study. An Augmented Reality based collaborative design workspace was developed, in which two main interaction techniques, Turn-table and Virtual Shadow, were incorporated to support shared manipulation and tele-presence. Turn-table provides intuitive shared manipulation of 3D models and physical cues for awareness of remote participants. Virtual shadow supports natural and continuous awareness of location, gestures and pointing of partners. A lab-based evaluation was conducted and the results showed that interaction techniques effectively supported awareness of general pointing and facilitated discussion in 3D model reviews. The workspace and the interaction techniques can facilitate more natural communication and increase the efficiency of collaboration on virtual 3D models between distributed participants (designer-designer, engineer, or modeler) in collaborative design environments.

• Journal of the Korea Fashion and Costume Design Association
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• v.7 no.3
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• pp.63-74
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• 2005

The cinema costume designers carry out the creative works in a different way from the commercial fashion designers generating the new trends by season or year for a number of people. Costumes created by the cinema costume designers are for the people acting in the film screens such as heroes, heroines or extras. The cinema costume designers should not miss the overall flow of a cinema. Moreover, the prominent designers have to devise the costumes livening up every scene. Most cinemas with the prudent interests and attention on the costumes are favored by the public and gain the commercial success. In particular, the cinemas emphasize the visual effects such as setting, lighting and computer graphics and require the substantial budgets for preparing the costumes regardless of genres, while all other industrial fields will be the same. Such efforts are to deliver the meaning and aesthetics that the cinemas intend to show through the designs, colors and textures of costumes closed up in each scene. The costumes in cinemas are another linguistic system and have the symbolic form of compound and meaningful communication used by the directors. The costume design is required to produce the costumes that liven up the characteristics of heroes or heroines as well as to fit for the general artistic effects of films. Moreover, it has to express the characters in the films using the costumes suitable for the film genres. Cinema costumes are defined and refined, and the process can be angst-ridden. Each frame of film is a canvas and has its own proscenuium. Every garment worn in a theatrical production is a costume. Before an actor speaks, his wardrobe has already spoken for him. From the most obvious and flamboyant show clothing, to contemporary clothes using subtle design language, costume design plays an integral part in every film production. Costume design is a vital tool for storytelling. Costumes have always had enormous influence on world fashion. Costume designers are passionate storytellers, historians, social commentators, humorists, psychologists, trendsetters and magicians who can conjure glamour and codify icons. Costume designers are project managers who have to juggle ever-decreasing wardrobe budgets and battle the economic realities of film production. Costume designers are artists with pen and paper, form, fabric and the human figure.

• International Journal of Highway Engineering
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• v.2 no.1
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• pp.135-145
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• 2000

A new procedure needs to be developed to predict the dynamic layer properties under moving truck loads. In this study, a computer code to evaluate layer moduli of asphalt concrete pavement from measured interior deflections at various depths were developed and verified from numerical model tests. Interior deflections of the pavement are measured from Multi-Depth Deflectometer(MDD). It was found that errors between the given and backcalculated moduli in numerical analysis were less than 0.32% for several numerical models tested. When impact loads were used, a technique to determine the depth to virtual rigid base was proposed through the analysis of compressive wave velocity and impulse loading durations. It was found that errors between the given and backcalculated moduli in numerical analysis were less than 0.114% when virtual rigid base was considered in numerical analysis. The pavement behavior must be evaluated under various vehicle speeds when determining the dynamic interaction between the loading vehicle and pavement system. To evaluate the dynamic behavior on asphalt concrete pavement under various vehicle speeds, truck moving tests were carried out. From the test results with respect to vehicle speed, it was found that the vehicle speed had significant effect on actual response of the pavement system. The lower vehicle speed generates the higher interior deflections, and the lower dynamic modulus.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.2
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• pp.95-105
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• 2001

A series of experiment is carried out to determine the holding power of the existing anchors used in the stationary gear in the coast of the South sea. The experiment apparatus is made of the pulling machine, the load cell, the personal computer and three water tanks the bottom of which are mud, sand and m & s respectively. The result obtained are as follows : 1. On the tension and holding power of the existing anchors, B-type of the stock anchor with two fluke shows the greatest and gets smaller on order of A-type one with a fluke. The holding power of the anchors shows the greatest in the mud and gets smaller in order of m & s, sand. And, the holding power depending upon the length of anchor rope increase as the length does up to the 4 times of depth. 2. On the holding power per fluke area of the existing anchors in case of ration of length of anchor rope to depth is 2, 3 and 4, A-type anchor shows about 310-320 kg/m supper(2), 470-480 kg/m supper(2), 590-640 kg/m supper(2) respectively, B-type one 260-265 kg/m supper(2), 390-450 kg/m supper(2), 630-700 kg/m supper(2) respectively, and C-type one 70-100 kg/m supper(2), 150-180 kg/m supper(2), 210-270 kg/m supper(2) respectively. The holding power per fluke area of the anchors increase as the length of anchor rope does. 3. On the coefficient of holding power of the existing anchors, A-type anchor shows the greatest and gets smaller in the order of B-type one, C-type one.

• Korean Journal of Veterinary Research
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• v.34 no.2
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• pp.259-266
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• 1994

The study was carried out to determine the pharmacokinetic parameters after intravenous(iv) and intramuscular(im) administration (10mg/kr) in healthy rabbits. The results obtained through the experiments were summarized as follows: 1. Bioassay (Bacillus cereus 11778) was evaluated very useful for the determination of oxytetracycline(OTC) in the rabbit serum and tissues, with the detection limit of $0.125{\mu}g/ml$. 2. The pharmacokinetic profiles of OTC (10mg/kg, iv) in rabbits were best described with a two compartment open model $(C=29.5e^{-4,3t}{\pm}3.6^{-0.2t})$, whereas that of OTC (10mg/kg, im) showed a one compartment curve fitting. 3. Following iv administration, a rapid distribution phase was predominant [$t_{\frac{1}{2}}({\alpha}):1.43{\pm}0.98hr$ (♂), $0.5{\pm}0.1hr$(♀)], and then more slow elimination phase ensued [$t_{\frac{1}{2}}({\beta}):4.52{\pm}0.76hr$(♂), $7.32{\pm}2.52hr$(♀)]. Other computer generated pharmacokinetic values were as follows:C1 [$67.76{\pm}18.59ml/kg/h$(♂), $76.03{\pm}22.98ml/kg/h$ (♀)] Vd [$257.74{\pm}180.47ml/kg$ (♂), $92.33{\pm}23.62$ (♀)] AUC [$25.6{\pm}4.44mgh/L$ (♂), $39.6{\pm}12.13mgh/l$ (♀)]. There were no statistical significance between both sexes for all the parameters at the confidence level of 95%. 4. After im administaration, the absorption from the injection sites was very rapid [ Ka:$0.18{\pm}0.03h^{-1}$ (♂), $0.24{\pm}0.02h^{-1}$ (♀)] followed by a monoexponential elimination fashion. The time to peak blood level (Tmax) were calculated $1.64{\pm}0.15hr$ and $1.34{\pm}0.24hr$, in the male and female, respectively. The peak levels (Cmax) at the corresponding time were $1.69{\pm}0.23{\mu}g/ml$ (♂) and $2.08{\pm}0.16{\mu}g/ml$ (♀), with no statistical differences (p>0.05).

• Nuclear Medicine and Molecular Imaging
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• v.43 no.5
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• pp.443-450
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• 2009

Purpose: Conventional image reconstruction uses simplified physical models of projection. However, real physics, for example 3D reconstruction, takes too long time to process all the data in clinic and is unable in a common reconstruction machine because of the large memory for complex physical models. We suggest the realistic distributed memory model of fast-reconstruction using parallel processing on personal computers to enable large-scale technologies. Materials and Methods: The preliminary tests for the possibility on virtual manchines and various performance test on commercial super computer, Tachyon were performed. Expectation maximization algorithm with common 2D projection and realistic 3D line of response were tested. Since the process time was getting slower (max 6 times) after a certain iteration, optimization for compiler was performed to maximize the efficiency of parallelization. Results: Parallel processing of a program on multiple computers was available on Linux with MPICH and NFS. We verified that differences between parallel processed image and single processed image at the same iterations were under the significant digits of floating point number, about 6 bit. Double processors showed good efficiency (1.96 times) of parallel computing. Delay phenomenon was solved by vectorization method using SSE. Conclusion: Through the study, realistic parallel computing system in clinic was established to be able to reconstruct by plenty of memory using the realistic physical models which was impossible to simplify.

• Journal of Internet Computing and Services
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• v.20 no.6
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• pp.85-93
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• 2019

Computational Science and Engineering is a convergence study that understands and solves complex problems such as science, engineering, and social phenomena through modeling using computing resources. Computational science and engineering combines algorithms, computational and informatics, and infrastructure. The importance of computational science is increasing with the improvement of computer performance and the development of large data processing technology. In Korea, Korea Institute of Science and Technology Information (KISTI) has been developing national computational science engineering software and utilization technology by combining basic science and computing technology through EDISON project. The EDISON project builds an open EDISON platform and integrates and services information systems in seven areas of computational science and engineering (computational thermal fluids, nanophysics, computational chemistry, structural dynamics, computational design, and computational medicine). Using this, we have established a web-based curriculum to lay the groundwork for fostering scientific talent and commercializing computational science and engineering software. The purpose of this study is to derive the quality characteristic factors of computational science platform and to empirically examine the effect on user satisfaction. This paper examines how the quality characteristics of information systems, the computational science engineering platform, affect the user satisfaction by modifying the research questions according to the propensity of the computational science platform by referring to the success factors of DeLone and McLean's information system. Based on the results of this study, we will suggest strategic implications for platform improvement by searching the priority of quality characteristics of computational science platform.