• International Journal of Railway
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• v.7 no.4
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• pp.100-108
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• 2014

A numerical analysis method for predicting aerodynamic noise at inter-coach space of high-speed trains, validated by wind-tunnel experiments for limited speed range, is proposed. The wind-tunnel testing measurements of the train aerodynamic sound pressure level for the new generation Korean high-speed train have suggested that the inter-coach space aerodynamic noise varies approximately to the 7.7th power of the train speed. The observed high sensitivity serves as a motivation for the present investigation on elucidating the characteristics of noise emission at inter-coach space. As train speed increases, the effect of turbulent flows and vortex shedding is amplified, with concomitant increase in the aerodynamic noise. The turbulent flow field analysis demonstrates that vortex formation indeed causes generation of aerodynamic sound. For validation, numerical simulation and wind tunnel measurements are performed under identical conditions. The results show close correlation between the numerically derived and measured values, and with some adjustment, the results are found to be in good agreement. Thus validated, the numerical analysis procedure is applied to predict the aerodynamic noise level at inter-coach space. As the train gains speed, numerical simulation predicts increase in the overall aerodynamic sound emission level accompanied by an upward shift in the main frequency components of the sound. A contour mapping of the aerodynamic sound for the region enclosing the inter-coach space is presented.

• Korean Journal of Social Welfare
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• v.47
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• pp.107-147
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• 2001

In the 1990s, with enacting of the laws on the family violence in Korea, agencies such as helpline 1366, counseling center and shelter for the female victims have been rapidly increasing in number. Also police and medical center have been viewed as having major responsibility for delivering services and social workers in community welfare center and public social worker have been expected play a role in community-based delivery systems for the female victims. The purpose of this study is to measure the level of the inter agency coordination and to find out the factors affecting the inter-agency coordination in family violence and to make policy implications for a better delivery system. The data were obtained from a social survey of family violence agencies, counselling center/shelter/helpline 1366, police, medical center, social workers of community center and of public sector in Seoul and Kyeongi area. The major results are as follows: 1) the level of inter-agency coordination is low, specially the referal cases of police and medical center is very poor. 2) The type of inter-agency coordination is referals and information sharing among agencies. 3) the factors affecting inter-agency coordination is agency type, wills and efforts of agency, information sharing, experience of family violence education. The current findings suggest that the delivery system to promote inter-agency coordination efforts and for police and medical center, social worker in private and public agency to respond promptly and properly would be built up.

• Journal of Broadcast Engineering
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• v.9 no.3
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• pp.214-224
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• 2004

In this paper, an adaptive spatio-temporal predictive coding based on the H.264 is proposed for 3D immersive media encoding, such as 3D image processing, 3DTV, and 3D videoconferencing. First, we propose a spatio-temporal predictive coding using the same view and inter-view images for the two TPPP, IBBP GOP (group of picture) structures 4hat are different from the conventional simulcast method. Second, an 2D inter-view direct mode for the efficient prediction is proposed when the proposed spatio-temporal prediction uses the IBBP structure. The 2D inter-view direct mode is applied when the temporal direct mode in B(hi-Predictive) picture of the H.264 refers to an inter-view image, since the current temporal direct mode in the H.264 standard could no: be applied to the inter-view image. The proposed method is compared to the conventional simulcast method in terms of PSNR (peak signal to noise ratio) for the various 3D test video sequences. The proposed method shows better PSNR results than the conventional simulcast mode.

• Journal of Information Display
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• v.5 no.1
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• pp.28-33
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• 2004

A high voltage NMOSFET is proposed to drive top emission organic light emitting device (OLED) used in the organic electroluminescent (EL) display on the single crystal silicon substrate. The high voltage NMOSFET can be fabricated by utilizing a simple layout technique with a standard CMOS logic process. It is clearly shown that the maximum supply voltage ($V_{DD}$) required for the pixel-driving transistor could reach 45 V through analytic and experimental methods. The high voltage NMOSFET was fabricated by using a standard 1.5 ${\mu}m$, 5 V CMOS logic process. From the measurements, we confirmed that the high voltage NMOSFET could sustain the excellent saturation characteristic up to 50 V without breakdown phenomena.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1270-1272
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• 2007

Analytic equations are derived from physical quantities in the gate-source overlap region and the concept of effective gate-source overlap length is proposed. The effective overlap length can be affected by gate voltage, insulator thickness and semiconductor thickness, and the overlap length should be larger than the length to obtain maximum driving current.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.1
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• pp.361-378
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• 2012

Most of the current frequency hopping (FH) based dynamic spectrum access (DSA) methods concern a reactive channel access scheme with synchronous inter-channel spectrum sensing, i.e., FH is reactively triggered by the primary user (PU)'s return reported by spectrum sensing, and the PU channel to be switched to is assumed precisely just sensed or ready to be sensed, as if the inter-channel spectrum sensing moments are synchronous. However, the inter-channel spectrum sensing moments are more likely to be asynchronous, which risks PU suffering more interference. Moreover, the spectrum sensing is usually erroneous, which renders the problem more complex. To address this problem, we propose a proactive FH based DSA method against both erroneous spectrum sensing and asynchronous inter-channel spectrum sensing (moments). We term it as proactive DSA. The optimal FH sequence is obtained by dynamic programming. The complexity is also analyzed. Finally, the simulation results confirm the effectiveness of the proposed method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.7A
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• pp.693-701
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• 2008

In OFDMA (Orthogonal Frequency Division Multiple Access) system that frequency reuse factor is 1, as the same channels in the neighborhood cells creates inter-cell co-channel interference which provides a resource underutilization problem, channel allocation schemes to minimize inter-cell interference have been studied. This paper proposes a new CNIR (Carrier to Noise and Interference Ratio)-based distributed Inter-cell DCA (Dynamic Channel Allocation) algorithm in the OFDMA environment with frequency reuse factor of 1. When a channel allocation is requested, if there is not a free channel in home cell or the available free channels in home cell do not satisfy a required threshold value, the proposed Inter-cell DCA algorithm finds CNIR values of available free channels in the neighborhood cells and then allocates a free channel with maximum CNIR value. Through the simulation results, we find that the proposed scheme decreases both new call block rate and forced termination rate due to new call generation at the same time because it increases channel allocation probability.

• Journal of Arbitration Studies
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• v.29 no.4
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• pp.3-31
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• 2019

In order to achieve full-scale economic cooperation between North Korea and South Korea, the Gaesong Industrial Complex should reopen first. In this case, the Inter-Korean commercial arbitration system should be clearly established to effectively resolve the disputes arising in the special economic zones of the Gaesong Industrial Complex. Even though the Inter-Korean Investment Security Agreement, the Agreement on the Resolution of Commercial Disputes between North Korea and South Korea, the Agreement on the Formation and Operation of the Inter-Korean Commercial Arbitration Committee, and the Agreement on the Formation and Operation of the Inter-Korean Commercial Arbitration Committee in the Gaesong Industrial District are in place, specific arbitration procedure is not concretely agreed upon and realized between the two Koreas. Therefore, the realization of commercial arbitration between them led by the Ministry of Unification or the government should be accomplished. In addition, it is necessary to consider the administrative trial or administrative litigation system in order to deal with administrative disputes that are not subject to commercial arbitration. Lastly, discussions on legal integration between the two Koreas should continue, focusing on the special economic zone of the Gaesong Industrial Complex, in order to prevent integration from being hindered by a different culture for a long time.

• Journal of East-West Nursing Research
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• v.26 no.1
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• pp.91-99
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• 2020

Purpose: The study aims to assess the inter-rater reliability of the Korean Triage and Acuity Scale between the research nurses and the triage nurses. Methods: Interrater reliability was measured on 400 adult (≧15) and 400 pediatric (<15) patients who visited the emergency medical center from January 4 to June 30, 2018. Results: The study result showed that the inter-rater reliability of the Korean Triage and Acuity Scale was substantial, with κ=.73 (95% Confidence interval= .68-.78) and 77.0 percent agreement. The inter-rater of Pediatric Korean Triage and Acuity Scale was also substantial, with κ=.76 (95% Confidence interval= .71-.82) and 83.8 percent agreement. Conclusion: Although the inter-rater reliability of the Korean Triage and Acuity Scale was acceptable, the percent agreement was lower than the desirable level (<80.0%). It was confirmed that Pediatric Korean Triage and Acuity Scale had an acceptable level of inter-rater reliability and percent agreement for clinical use. Efforts should be made to improve the reliability in the future.

• Journal of Physiology & Pathology in Korean Medicine
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• v.32 no.4
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• pp.185-196
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• 2018

The purpose of this study is to evaluate the current inter-expert agreement of Sasang Constitution Medicine (SCM), to expand the current knowledge on the causes of imperfect inter-expert agreement, and to explore possible solutions for improving inter-expert agreement. A literature search was conducted to gather data on the studies on diagnosis of SCM. The 127 articles included in this analysis had a mean 4.1 publications per year, 56.0% published in the Journal of Sasang Constitutional Medicine between the year of 1987 and 2017. SCM specialist participated in 96.3% of all the expert judgment cases. Inter-expert agreement was reported in 14.8% of the cases that had two or more experts. We recommend that expert panels integrate the results of current status of diagnostic consensus into guideline development and strengthen expert education and training with the aim of improving SCM diagnostic accuracy.