• Journal of the Institute of Electronics Engineers of Korea SC
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• v.39 no.1
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• pp.66-75
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• 2002

For the theoretical performance analysis of Viterbi Decoder for wireless LAN with data rate 12Mbps, code rate 1/2 and constraint length 7 defined in IEEE 802.11a, the transfer function is derived using Cramer's rule and the first-event error probability and bit error probability is derived under the AWGN. In the design process, input symbol is quantized into 16 steps for 4 bit soft decision and register exchange method instead of memory method is proposed for trace back, which enables the majority at the final decision stage. In the implementation, the Viterbi decoder based on parallel architecture with pipelined scheme for processing 12Mbps high speed data rate and AWGN generator are implemented using FPGA chips. And then its performance is verified in real time.

• The Journal of the Korea Contents Association
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• v.14 no.10
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• pp.279-286
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• 2014

In this study, the local government proposes to improve agricultural products of the mall. Based on precedent studies, the variables that influence Customer Satisfaction are defined as; Product Quality, Delivery, Price. The result of study model verification is as below. Product Quality, Delivery and Price have positive influence on Customer Satisfaction. Price and Customer Satisfaction have positive influence on Repurchasing intention. Agricultural products through e-commerce transactions is increasing. But, the decreasing sales of professional Mall. Agricultural products have a variety of distribution channels. Because of the distribution system in a variety of price differences. People think that the most important factor is the price. Improvement is as follows. (1) To offer accurate product information, (2) Continuous content maintenance, (3) Conducted a variety of events, (4) To provide consumers with various benefits, (5) Offer a variety of product configurations, (6) Select the appropriate sales methods, (7) Provide ease of search.

• The korean journal of orthodontics
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• v.34 no.6 s.107
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• pp.537-543
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• 2004

Microsatellit markers are considered to be very promising genetic markers for genetic linkage analysis. The majority of the markers are as informative as in Caucasians but there are significant ethnic differences in the genetic variations. In order to investigate the genetic variations in the Korean and Japanese populations and their ethnic differences, 51 microsatellite marker loci spanning the whole human chromosome 1 were arranged from a commercially available set (ABI PRISM Linkage Mapping Set-HD5, Applied Biosystems, Foster City, CA, USA), and then determined the allelic frequencies and heterozygosities for these marker loci in the 90 unrelated Korean subjects and 90 unrelated Japanese subjects. Of all 51 markers tested, significant differences were observed when microsatellite allele frequency pattern of Korean was compared with those of Caucasian, while this pattern was highly similar between Korean and Japanese populations. Our data indicate that an extensive verification of public microsatellite markers in a particular population study should be undertaken prior to their linkage studies. Moreover, this information should facilitate genetic linkage studies of various hereditary diseases, especially in the Koreans and Japanese.

• Journal of the Korea Society for Simulation
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• v.17 no.4
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• pp.51-60
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• 2008

The purpose of this study is the use of simulation modelling to enhance productivity. In this paper, the optimal buffer allocation of small and medium size industries which produce solenoid valves for automobiles, is performed using simulations. The simulation model was developed under considerations of production layout, process & operation, process time, total work time, WIP, utilization, failure rate, and operation efficiency as inputs, and it was validated with careful comparisons between real behaviors and simulation outputs of the production line. Therefore, we can evaluate effects and changes in productivity when some strategies and/or crucial factors are changed. Although too large buffer could decrease productivity, the solenoid production line in this paper has been maintained large buffer. It is because reducing the size of buffer could result in the termination of the process. We determined the optimal number of buffers that could not cause any interrupt in productions using simulations. This simulation model considers diverse input variables which could influence productivity, and it is very useful not only for the production line of solenoid valves, but also for other production lines with various purposes, especially, small and medium size industries.

• The Journal of Korean Association of Computer Education
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• v.10 no.6
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• pp.29-38
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• 2007

The purpose of this study is developing of Korean scale for measuring elementary school pupil's online game addiction tendency by scientific development process. The pilot test was conducted in three times, and the items analysis, reliability analysis, and factor analysis was conducted at every test, so the inquiries for main survey composed of 30 inquiry items was decided. Some referential variables was included in the inquiries for main survey such as inquiry items for testing the actual using conditions and attitude of online game, the aggressive behavior scale, the impulsive behavior scale, the solitude scale, and the self-control scale. 2,584 fifth and sixth grade students in elementary school participated in main survey. For main survey results, items analysis and reliability analysis was conducted and validity was verified by exploratory factor analysis and correlation analysis. Finally, the final inquiry items composed of 7 factors, 30 items and the grouping criterion were developed through the standardization process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7564-7574
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• 2015

This study confirmed by a meta-analysis of the effect of suppressing the size of the turnover variable based on the thesis concerning "turnover intention" of the past 15 years, and the trend over the year, according to published meta-regression analysis was verified. The overall effect size for the study was found to inhibit factors medium effect size. Effect size is a private property factor by lower variable salary levels, age and marital status, working period, turnover experience, educational level, showed a work order forms, job characteristics factor is job satisfaction, working conditions, job importance, firm relationships with colleagues, showed a net job autonomy. In addition, organizational characteristic factor effect sizes organizational commitment, organizational commitment, advancement opportunities, compensation satisfaction, organizational justice, participatory doctor had determined the net. Changes in accordance with the published year is closer to 2015 it showed that the effect of inhibiting factors reduced size.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.194-194
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• 2012

본 연구에서는 자연하천에서 Rhodamine-WT를 이용하여 추적자 실험을 수행하고 이를 바탕으로 오염사고대응예측모델에 대한 검증을 실시하고자 하였다. 최근 국내에서는 다양한 형태와 규모의 수질오염사고가 매년 수십건 이상 발생하고 있으며, 따라서 수치모형 기반의 수질오염 사고 대응 예측시스템에 대한 높은 신뢰성이 요구되고 있다. 수질사고에 노출되어 있는 지표수를 각종 용수로서 안전하게 공급하기 위해서는 정확한 수질예측이 필수적이며, 이를 위해서 수십 년간 연구되어 온 수질모델을 오염사고 대응예측시스템에 적합하도록 정확성과 신뢰성을 갖추기 위한 연구가 진행되어야 한다. 수치 모형을 이용한 물질의 이송 및 확산 모의에서는 오염물질 도달시간과 확산 농도를 결정하는 것이 가장 중요한 요소이므로 이송 및 확산 모의에 대한 검증 기법 개발 및 적용이 필요하다. 본 연구에서는 낙동강수계 지류하천인 감천에서 추적자 실험을 4회 실시하여 측정한 수리량과 농도 실측치를 이용하여 분산계수를 종 횡분산계수 산정이 가능한 2차원 유관추적법을 적용하여 산정하였다. 각 단면에 유속은 ADV-3차원 유속계인 Flow-Tracker를 사용하여 도섭으로 측정하였으며 하천의 흐름 방향의 직각으로 측선을 설치하고 펌프를 이용하여 채수를 한 다음 Rhodamie WT의 농도를 측정하였으며 측선의 위치 보정은 GPS를 통하여 보정하였다. 측정 자료를 이용하여 2차원 유관추적법으로 분산계수를 산정한 결과 각각의 측선에 따라서 다소 차이가 발생하였으며, 일부 구간에서는 이론식으로 계산한 분산계수와 근사한 값이 나타났다. 이는 사주가 매우 발달하고 만곡이 많은 실험구간의 특성상 Elder와 Fischer 식으로 계산한 값과 차이가 발생할 가능성이 높은 구간이기 때문인 것으로 판단된다. 또한 하폭에 대한 수심비가 커질수록 분산계수도 증가하고 평균유속에 대한 전단유속에 비에 비례하는 것으로 나타났다.

• Journal of Korea Water Resources Association
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• v.50 no.8
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• pp.563-577
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• 2017

As the uncertainty of precipitation increases due to climate change, seasonal forecasting and the use of weather forecasts become essential for efficient water resources management. In this study, the categorical probabilistic long-term forecasts implemented by KMA (Korea Meteorological Administration) since June 2014 was evaluated using assessment indicators of Hit Rate, Reliability Diagram, and Relative Operating Curve (ROC) and a technique for obtaining quantitative precipitation estimates based on probabilistic forecasts was proposed. The probabilistic long-term forecasts showed its maximum predictability of 48% and the quantified precipitation estimates were closely matched with actual observations; maximum correlation coefficient (R) in predictability evaluation for 100% accurate and actual weather forecasts were 0.98 and 0.71, respectively. A precipitation quantification approach utilizing probabilistic forecasts proposed in this study is expected to enable water management considering the uncertainty of precipitation. This method is also expected to be a useful tool for supporting decision-making in the long-term planning for water resources management and reservoir operations.

• Fire Science and Engineering
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• v.18 no.1
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• pp.42-48
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• 2004

The deterministic modeling techniques like Zone model and Field model are mainly used for thermal distribution and smoke flow at fire case in multi use facilities. While Zone model analyse fire simulation by dividing spaces by 2 section, the Field model dividing many cells. However, the difficultly follows to prove efficiency between the two models when it applys. Therefore new modeling development is required which in closes to real situation by verify number algorithm and related data for fire modeling. The paper analyses the efficiency of two different fire modeling at interior spaces of multiplex cinema theater. It is found that the zone model for average distribution and the field model for detail space phenomenon are relevant to apply. Also, Filed model is useful to the result that fire analysis and position of detector and review for smoke control system.

• The KIPS Transactions:PartD
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• v.16D no.4
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• pp.561-570
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• 2009

In order to manage repair and maintenance efficiently in the mobile environment, the system structure to manage service as a policy and the policy description language are needed. This research defined the structure of PEP, which is the executioner of policy in the IETF policy framework, and proposed the policy description language which can be carried out under the PEP structure. The proposed policy description language derived demand matters based on documentary data and the characteristics of mobile and the policy information model was designed with the three stage approaches and was defined as policy description language. The three stage approaches are made up of the policy domain that decides the scope to which the policy applies, the policy rules which distinguish the kinds of policy application and control, and policy grammar which contextualizes the policy structure. In order to verify the efficiency of the policy description language, scenarios are defined with the policy description language and verified it by using policy tool and proved the expansive nature by comparing and analyzing other policy description language.