• Journal of Broadcast Engineering
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• v.14 no.5
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• pp.573-588
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• 2009

In this paper, we propose a novel video quality degradation monitoring scheme titled VR-VQMS(Visual Rhythm based Video Quality Monitoring Scheme) over an IPTV service prone to packet losses during network transmission. Proposed scheme quantifies the amount of quality degradation due to packet losses, and can be classified into a RR(reduced-reference) based quality measurement scheme exploiting visual rhythm data of H.264-encoded video frames at a media server and reconstructed ones at an Set-top Box as feature information. Two scenarios, On-line and Off-line VR-VQMS, are proposed as the practical solutions. We define the NPSNR(Networked Peak-to-peak Signal-to-Noise Ratio) modified by the well-known PSNR as a new objective quality metric, and several additional objective and subjective metrics based on it to obtain the statistics on timing, duration, occurrence, and amount of quality degradation. Simulation results show that the proposed method closely approximates the results from 2D video frames and gives good estimation of subjective quality(i.e.,MOS(mean opinion score)) performed by 10 test observers. We expect that the proposed scheme can play a role as a practical solution to monitor the video quality experienced by individual customers in a commercial IPTV service, and be implemented as a small and light agent program running on a resource-limited set-top box.

• Journal of the Korean Vacuum Society
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• v.10 no.1
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• pp.98-103
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• 2001

A new application of dirchroic mirror for the improvement of luminance and luminous efficacy in an AC-Plasma Display Panel (PDP) is suggested. Only about half of the Vacuum Ultraviolet (VUV) generated in the reflective PDP cell is used for the excitation of the phosphor. We are suggesting an idea of adopting a dichroic mirror which can reflect the VUV toward the phosphor which otherwise is absorbed by the front panel. The optical constants of the thin films of dirhroic mirror were determined from the photometric measurements through an iteration process of matching calculated and measured values of the reflectance and transmittance in the VUV wavelength region. From these results, we could design such a filter whose high reflection zone is centered at 147nm by a computer simulation accurately. The 147nm VUV is radiated from Xenon 3Pl state which is dominantly used to activate the phosphor in the PDP cell. The dichroic mirror was made with an electronbeam evaporator and its reflectance was measured by a reflectometer. We confirmed the usefulness of the dichroic mirror for the improvement of efficiency with experiments done by test panels. The panel with mirror shows improved luminance and luminous efficacy by 20∼30％.

• Geophysics and Geophysical Exploration
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• v.13 no.3
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• pp.286-294
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• 2010

Korea Institute of Geoscience and Mineral Resources (KIGAM) has installed and operated seven seismoacoustic (infrasound) arrays as well as seismic stations in Korea. The seismo-acoustic array, which consists of co-located seismometers and micro-barometers, can observe both seismic and infrasonic signals from distant explosive phenomena. The infrasound is defined as low frequency (<20 Hz) acoustic waves in atmosphere. In particular, it can be detectable at long distance due to its low energy attenuation during propagation in atmosphere. KIGAM adopted the infrasound technology to discriminate surface explosions from earthquakes only because the surface explosion generally generates infrasound following seismic signal. In addition to surface explosions, these arrays have detected diverse geophysically natural and artificial phenomena, such as infrasound signal from the North Korean nuclear test. This review introduced the state-of-the-art studies and examples of infrasonic signals in and around the Korean Peninsula. In conclusion, infrasound technology would be clearly accepted itself as a new Earth monitoring technology by expanding its detectable regime to lithosphere-Earth surface-atmosphere. In future, an advanced technology, which allows to analyze seismic and infrasonic wave fields together, will enlarge the understanding of geophysical phenomena and be used as a robust analysis method for remote explosive phenomena in the broad infrasound regime.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1993.10a
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• pp.12-19
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• 1993

In general, the line balancing problem is defined as of finding an assignment of the given jobs to the workstations under the precedence constraints given to the set of jobs. Usually, the objective is either minimizing the cycle time under the given number of workstations or minimizing the number of workstations under the given cycle time. In this paper, we present a new type of an assembly line balancing problem which occurs in an electronics company manufacturing home appliances. The main difference of the problem compared to the general line balancing problem lies in the structure of the precedence given to the set of jobs. In the problem, the set of jobs is partitioned into two disjoint subjects. One is called the set of fixed jobs and the other, the set of floating jobs. The fixed jobs should be processed in the linear order and some pair of the jobs should not be assigned to the same workstations. Whereas, to each floating job, a set of ranges is given. The range is given in terms of two fixed jobs and it means that the floating job can be processed after the first job is processed and before the second job is processed. There can be more than one range associated to a floating job. We present a procedure to find an approximate solution to the problem. The procedure consists of two major parts. One is to find the assignment of the floating jobs under the given (feasible) assignment of the fixed jobs. The problem can be viewed as a constrained bin packing problem. The other is to find the assignment of the whole jobs under the given linear precedence on the set of the floating jobs. First problem is NP-hard and we devise a heuristic procedure to the problem based on the transportation problem and matching problem. The second problem can be solved in polynomial time by the shortest path method. The algorithm works in iterative manner. One step is composed of two phases. In the first phase, we solve the constrained bin packing problem. In the second phase, the shortest path problem is solved using the phase 1 result. The result of the phase 2 is used as an input to the phase 1 problem at the next step. We test the proposed algorithm on the set of real data found in the washing machine assembly line.

• Journal of Pharmaceutical Investigation
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• v.31 no.2
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• pp.131-136
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• 2001

Tofisopam is a new type of tranquilizer valuable for the relief of anxiety and tension in a wide range of emotional disorders. Tofisopam has the therapeutic characteristics of a minor tranquilzer and a mild stimulatory effect. The purpose of the present study was to evaluate the bioequivalence of two tofisopam tablets, $Grandaxin^{TM}$ (Hwan In Pharmaceutical Co., Ltd.) and $Tofim^{TM}$ (Kyung Dong Pharmaceutical Co., Ltd.), according to the guidelines of Korea Food and Drug Administration (KFDA). Eighteen normal male volunteers, $23.11\;{\pm}\;2.83$ years in age and $65.43\;{\pm}\;7.64\;kg$ in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After one tablet containing 50 mg of tofisopam was orally administered, blood was taken at predetermined time intervals and the concentrations of tofisopam in serum were determined using HPLC method with UV detector. The pharmacokinetic parameters such as $AUC_t$, $C_{max}\;and\;T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters. The results showed that the differences in $AUC_t$, C_{max}\;and\;T_{max}$ between two tablets based on the $Grandaxin^{TM}$ were -5.59%, 2.22% and -13.18%, respectively. Minimum detectable differences $({\Delta})$ at ${\alpha}=0.10$ and $1-{\beta}=0.8$ were less than 20% (e.g., 14.95% and 19.34% for $AUC_t\;and\;C_{max}$, respectively). The powers $(1-{\beta})$ at ${\alpha}=0.10$, ${\Delta}=0.2$ for $AUC_t$ and $C_{max}$ were 95.21% and 81.93%, respectively. The 90% confidence intervals were within {\pm}20%$ (e.g., $-15.64{\sim}4.45$ and $-10.77{\sim}15.21$ for $AUC_t\;and\;C_{max}$, respectively). Two parameters met the criteria of KFDA for bioequivalence, indicating that $Tofim^{TM}$ tablet is bioequivalent to $Grandaxin^{TM}$ tablet.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.282-293
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• 2019

Purpose: After developing and imparting knowledge of a simulation-based emergency airway management education program for nursing students, this study identified the effects of the education by evaluating emergency airway management knowledge, Clinical Performance Ability, self-efficacy, and critical thinking disposition. Method: The participants were 30 nursing students. Data were collected from October 14 to November 11, 2017, and analyzed using IBM SPSS Version 22.0. Results: The simulation-based nursing education program was developed and applied based on the ADDIE model involving five stages: analysis, design, development, implementation and evaluation. Comparing the pre-and post-education results, we observed statistically significant improvement when considering emergency airway management knowledge (t=-9.98, p<0.001), Clinical Performance Ability (t=-23.90, p<0.001), self-efficacy (t=-16.77, p<0.001), and critical thinking disposition (t=-5.04, p<0.001). Conclusions: Simulation-based emergency airway management training program is an effective educational program that enhances the emergency airway management knowledge, Clinical Performance Ability, self-efficacy, and critical thinking disposition of nursing students. We believe that the program developed in this study contributes towards improvement of patient nursing quality by enhancing the ability of nursing students to cope with emergencies in practice. Furthermore, it can be applied for educating new nursing students, and contribute to the development of nursing practices.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.147-154
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• 2018

This paper focuses on the development of a support system that can rapidly generate the design data of a hot-form die with cooling channels, commonly known as hot stamping technology. We propose a new process for designing hot-form dies based on our (automated) system, whose main features are derived from the analysis of the design requirements and design process in the current industry. Our design support system consists of two modules, which allow for the generation of a 3D geometry model and its 2D drawings. The module for 3D modeling automation is implemented as a type of CATIA template model based on CATIA V5 Knowledgeware. This module automatically creates a 3D model of a hot-form die, including the cooling channels, that depends on the shape of the forming surface and the number of STEELs (subsets of die product) and cooling channels. It also allows for both the editing of the positions and orientations of the cooling channels and testing for the purpose of satisfying the constraints on the distance between the forming surface and cooling channels. Another module for the auto-generation of the 2D drawings is being developed as a plug-in using CAA (CATIA SDK) and Visual C++. Our system was evaluated using the S/W test based on a user defined scenario. As a result, it was shown that it can generate a 3D model of a hot form die and its 2D drawings with hole tables about 29 times faster than the conventional manual method without any design errors.

• The Korean Journal of Cytopathology
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• v.7 no.1
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• pp.1-11
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• 1996

From the concepts of cellular pathology and of exfoliative cytology, as elucidated by Virchow and Papanicolaou respectively in the late 19th and early 20th century, have evolved the primary methods for the diagnosis of cancer today. From Papanicolaou's concept of exfoliative cytology developed fine needle aspiration biopsy in the early 1960's, this has become a major diagnostic procedure and has contributed to a significant reduction in open biopsies and, therefore, to medical cost-effectiveness immunobiochemical techniques provided us with a supplement to cancer diagnosis in the 1980's. The immunoperoxidase method, using monoclonal antibodies, is applied primarily as an ancillary measure to elucidate the nature of cancers The availability of specific monoclonal antibodies has greatly facilitated the identification of cell products or surface markers. For example, antibodies directed against intermediate filaments have proved to be of value in determining the histogenesis oi poorly differentiated neoplasms. Tumor markers may serve as biochemical indicators of the presence of a neoplasm. They can be detected In plasma and other body fluids. Their concentration can be applied as a diagnostic test, for monitoring the clinical course of known cancer, and as a screening measure to detect certain cancers in a population at risk. Flow cytometry is a useful tool for distinguishing several cell characteristics, such as the immunophenotype of leukemia-lymphoma cells, the DNA content of neoplastic cells, and cell proliferation rate. Molecular biologic techniques provided a giant step for the management of cancer patients encompassing diagnosis, prognostic evaluation, and therapy. Nucleic acid hybridization techniques are utilized as Southern, Northern, and dot blots and in situ hybridization. Molecular biology and its techniques may bring a blight new horizon for understanding cancer biology and in designing therapy on the basis of gene manipulation.

• The Korean Journal of Pesticide Science
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• v.8 no.2
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• pp.117-128
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• 2004

The influence of different feeding rates of three green algae on growth and reproduction in four Korean cladocera, Daphnia sp., Daphnia obtusa, Moina macrocopa, and Simocephalus vetulus was investigated. The growth and reproduction rates of Daphnia sp. fed Chlorella vulgaris cells were significantly increased than those of daphnid fed Senedesmus subspicatus and Selenastrum carpricornutum. The total offsprings of Daphnia sp. fed $25\times10^4$ and $50\times10^4$ cells Chlorella vulgaris for 21days were $124{\pm}2.8$ and $168{\pm}22.1$, respectively. The Daphnia obtusa fed $25\times10^4$ and $50\times10^4$ cells Selenastrum carpricornutum was shown good reproduction rates, $72.2{\pm}7.9$ and $79.6{\pm}22.9$, respectively. The Moina macrocopa fed $25\times10^4$ and $50\times10^4$ cells Senedesmus subspicatus as well as Simocephalus vetulus and $25\times10^4$ and $50\times10^4$ cells Chlorella vulgaris were shown good reproduction rates. All of algae tested were sufficient as a good diet for Korean Cladocerans in this study. However, the preferred alga was Chlorella vulgaris and the optimal feeding concentrations were $2.5\times10^5\sim5\times10^5$ cells/mL, because the alga was shown most stable and generally high production rates in all cladocerans tested.

• The Journal of Korean Medicine
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• v.29 no.2
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• pp.182-192
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• 2008

Objective: The purpose of this study was to evaluate on the antimicrobial effect on the periodontal pathogens and anti-inflammatory effect of Eriobotryae folium. Eriobotryae folium are constituent herbs of Gagamgamroum, which has been used for a long time in oriental medicine as a herbal medicine for treating halitosis and toothache. Method: Eriobotryae folium was prepared by extracting medicinal herb with water. We investigated antimicrobial activity by the minimum inhibitory concentration (MIC) test. We also investigated inhibition of $IL-1{\beta}-induced$ collagenase (mmp-1), stromelysin-1 (mmp-3), interleukin-6 gene expression in human gingival fibroblasts using RTPCR analysis. Result: The antimicrobial effects of Eriobotryae folium was evaluated with MIC against periodontopathogens; Porphyromonas gingivalis 2561, W50, A7A1-28, 9-14K-1, Prevotella intermedia 28, and Actinobacillus actinomycetemcomitans Y4. MICs of Eriobotryae folium were 1.25 mg/ml, 2.5 mg/ml, 0.625 mg/ml, 1.25 mg/ml, 10 mg/ml and 10 mg/ml. The anti-inflammatory effect of Eriobotryae folium was evaluated with influence of herbs on the $IL-1{\beta}-induced$ expression of mmp-1, mmp-3, and interleukin-6. $IL-1{\beta}$ increased mmp-1, mmp-3, and interleukin-6 mRNA levels. Eriobotryae folium significantly inhibited $IL-1{\beta}-induced$ mmp-1, mmp-3, and interleukin-6 gene expressions in a dose-dependent manner. Conclusion: These results suggested that Eriobotryae folium might reduce the excessive proteolytic capacity of the gingival fibroblast during inflammation and could be developed as a new drug for periodontitis.