• 한국콘텐츠학회논문지
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• 제6권3호
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• pp.1-11
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• 2006

정보통신기술의 발달로 광대역 통신망에서의 서비스들은 지연, 셀 손실 확률, 지터 요구사항들이 트래픽의 특성에 따라 매우 다양하다. 따라서 광대역망에서 다양한 트래픽의 종류에 따른 셀 손실율과 셀 지연율의 요구사항을 만족시킬 수 있는 제어시스템의 설계는 매우 중요한 요소이다. 본 논문에서는 트래픽의 각 클래스 타입에 따라 셀 카운터와 윈도우 카운터를 이용한 우선순위 제어 기법을 제안하였다. 제안한 기법에서는 요구된 서비스의 질을 만족시키기 위해 셀 카운터와 윈도우 카운터의 비교에 의해 얻어진 셀 손실과 지연 요소를 획득하여 우선순위 제어를 수행하였다. 그리고 컴퓨터 시뮬레이션을 통하여 성능을 평가하였다. 시뮬레이션 결과 셀 손실은 비디오, 데이터, 음성 순서로, 지연시간은 비디오, 음성, 데이터 순서의 결과를 보여 각 클래스의 요구조건을 만족시키는 우선순위제어 기법임을 확인할 수 있었다.

• 유통과학연구
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• 제14권10호
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• pp.153-164
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• 2016

Purpose - In general, large companies have larger organizations, funds, and systems to provide more effective and efficient services in the market. However, development needs to support the livelihood of ordinary citizens who work for small businesses as well. This research suggests that a new distribution channel, called a "foothold style Kosa mart," that cooperates jointly with a distribution center and a large discount mart can provide direct solutions to small and mid-size distributors. This new distribution channel can achieve a limited type of "Nadle shop (small supermarket) foster project" related to building a joint distribution center and improvement in wholesale supply. Research design, data, and methodology - Data about the Korea distribution situation, the Nadle stores, and the logistics centers were collected from literature, Statistics Korea, journals, and reports. Specifically, we investigated information about Kosa Mart and Nadle stores. We focused on the redesign of the distribution center for the Nadle store. Results - The Kosa Mart distribution center now includes 18 warehouses, and has been handling 2000-3000 items. Most of the warehouses have been simply designed and items loaded and stored without refrigeration; thus, it is possible to store only products of certain manufactured goods. The current logistics center has no wholesale function because it failed to resolve the joint purchasing and product supply issues of competitively priced products. Conclusions - This study aimed to identify ways to strengthen the competitiveness of small- and medium-sized retailers. A Kosa Mart redesign aims to unifying the logistics center, stores, and customers. First, the joint wholesale logistics system, equipped with an integrated ordering system, needs to process customer orders and store orders at the same time. Second, excellent small business product development has to connect with production. Third, the store composition needs to support a shipping hub. Fourth, the Mart differentiates itself from convenience store goods by supplying regional and specialized products to customers. Fifth, a service buying agent and direct transactions between producers and consumers need to be established, and exhibits and displays of goods need to be improved.

• Environmental Engineering Research
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• 제15권4호
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• pp.215-223
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• 2010

This study attempted to develop and suggest a more appropriate method for the determination of event mean concentration (EMC) and pollutant removal efficiency of a stormwater best management practice (BMP) considering rainfall. The stormwater runoff and hydrologic data gathered from 22 storm events during a 28-month monitoring period on a swirl and filtration type of BMP were used to evaluate the developed methods. Based on the findings, the modified EMC method resulted in lower (average) values than the overall EMC, although the differences were not significant (P>0.05). By comparison, the developed 'Rainfall Occurrence Ratio' (ROR) method was most significantly correlated (r=0.967 to 988, P<0.009) with the other existing removal efficiency determination methods such as the 'Efficiency Ratio' (ER), 'Summation of Loads' (SOL) and 'Regression of Loads' (ROL) methods. In addition, the ROR method gave the highest efficiency values, with no significant differences with any of the pollutant parameters, unlike the other three methods. These results were obtained because the ROR method integrated both pollutant loading and rainfall, which are not considered by the other three methods. Therefore, this study proved the suitability of the modified EMC and ROR methods for application in other BMP monitoring studies.

• Journal of Astronomy and Space Sciences
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• 제19권3호
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• pp.215-224
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• 2002

This paper describes EGSE design for the small satellite such like KOMPSAT-2 satellite. Recent design trend of small satellite and EGSE is to take short development time and less cost. For this purpose, the design for KOMPSAT-2 satellite and EGSE are not much modified from KOMPSAT-1 heritage. It means that it is able to be accommodated the verified hardware and software modules used in KOMPSAT-1 satellite program if possible. The objective of EGSE is to provide hardware and software for efficient electrical testing of integrated KOMPSAT-2 satellite in three general categories. (1) Simulators for ground testing (e.g. solar-simulation power, earth scenes, horizons and sun sensor). (2) Ground station type satellite data acquisition and processing test sets. (3) Overall control of satellite using hardline datum. In KOMPSAT (KOrea Multi-Purpose SATellite) program, KOMPSAT-2 EGSE was developed to support satellite integration and test activities. The KOMPSAT-2 EGSE was designed in parallel with satellite design. Consequently, the KOMPSAT-2 EGSE was based on the KOMPSAT-1 heritage since the spacecraft design followed the heritage. The KOMPSAT-2 baseline was elaborated by taking advantage of experience from KOMPSAT-1 program. The EGSE of KOMPSAT-2 design concept is generic modular design with preference in part selection with commercial off-the-shelf which were proven from KOMPSAT-1 programs, flexible/user friendly operational environment (graphical interface preferred), minimized new design and self test capability.

• 한국강구조학회 논문집
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• 제23권6호
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• pp.725-736
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• 2011

합성보에는 강재보와 철근콘크리트 슬래브의 경계면에서 작용하는 수평전단력에 저항하기 위해 전단연결재를 설치한다. 또한 일반적으로 강재보에는 거푸집용 철선일체형 데크플레이트가 주로 사용되는데 시공 중 데크플레이트의 탈락 및 낙하 등 안전을 확보하기 위해 철근트러스 거더가 끝나는 양단부의 상부철선에 직봉을 설치한다. 따라서, 본 연구는 이형철근과 강판을 이용하여 동등 이상의 내력을 확보하면서 직봉의 기능을 포함하는 새로운 형상의 전단연결재를 개발하고 활용하는 방안을 검토하였다. Push-out 실험결과, 이형철근과 강판을 사용한 전단연결재는 ${\phi}16$ 스터드커넥터 이상의 내력과 연성을 확보하였으며, 직봉과 전단연결재를 겸용하는 것이 가능한 것으로 나타났다.

• Plant Biotechnology Reports
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• 제5권3호
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• pp.217-224
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• 2011

Non-heading Chinese cabbage (Brassica rapa L. ssp. chinensis) is a popular vegetable in Asian countries. The diamondback moth (DBM), Plutella xylostella (L.), an insect with worldwide distribution, is a main pest of Brassicaceae crops and causes enormous crop losses. Transfer of the anti-insect gene into the plant genome by transgenic technology and subsequent breeding of insect-resistant varieties will be an effective approach to reducing the damage caused by this pest. We have produced transgenic non-heading Chinese cabbage plants expressing the potato proteinase inhibitor II gene (pinII) and tested the pest resistance of these transgenic plants. Non-heading Chinese cabbages grown for 45 days on which buds had formed were used as experimental materials for Agrobacterium-mediated vacuum infiltration transformation. Forty-one resistant plants were selected from 1166 g of seed harvested from the infiltrated plants based on the resistance of the young seedlings to the herbicide Basta. The transgenic traits were further confirmed by the Chlorophenol red test, PCR, and genomic Southern blotting. The results showed that the bar and pinII genes were co-integrated into the resistant plant genome. A bioassay of insect resistance in the second generation of individual lines of the transgenic plants showed that DBM larvae fed on transgenic leaves were severely stunted and had a higher mortality than those fed on the wild-type leaves.

• 한국물환경학회지
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• 제36권5호
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• pp.373-384
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• 2020

Hydrological models are based on a combination of parameters that describe the hydrological characteristics and processes within a watershed. For this reason, the model performance and accuracy are highly dependent on the parameters. However, model uncertainties caused by parameters with stochastic characteristics need to be considered. As a follow-up to the study conducted by Choi et al (2020), who developed a relatively simple semi-distributed hydrological model, we propose a tool to estimate the posterior distribution of model parameters using the Metropolis-Hastings algorithm, a type of Markov-Chain Monte Carlo technique, and analyze the uncertainty of model parameters and simulated stream flow. In addition, the uncertainty caused by the parameters of each version is investigated using the lumped and semi-distributed versions of the applied model to the Hapcheon Dam watershed. The results suggest that the uncertainty of the semi-distributed model parameters was relatively higher than that of the lumped model parameters because the spatial variability of input data such as geomorphological and hydrometeorological parameters was inherent to the posterior distribution of the semi-distributed model parameters. Meanwhile, no significant difference existed between the two models in terms of uncertainty of the simulation outputs. The statistical goodness of fit of the simulated stream flows against the observed stream flows showed satisfactory reliability in both the semi-distributed and the lumped models, but the seasonality of the stream flow was reproduced relatively better by the distributed model.

• 대한통합의학회지
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• 제7권4호
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• pp.283-290
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• 2019

Purpose : The purpose of this study was to find out how changes in body shape of obese patients could be affected by the combined management of diet and psychotherapy along with exercise therapy to control energy imbalance, the cause of obesity. Methods : In this study, the aerobic exercise program was conducted on 12 industrial workers of "D" company for a total of eight weeks for obese patients with a high body mass index (25 kg/㎡ or higher). The experimental group did not apply the program three times a week. The body type analysis was carried out using the body analyzer (Inbody 770, Inbody, Korea) and blood test and psychological test were performed after 8 weeks of exercise before and after exercise. Results : The results of the group showed a change in weight loss of 6.03 kg (p=.000) on average, which is nearly 10 % of the change in weight. It was also shown that the BMI (body mass index) decreased by 1.76 kg/㎡ (p=.000). Abdominal fat (AO) is also 0.14 % (p=.000), waist circumference (WC, 12.72 cm, p=.000), internal fat (VF, 25.12 %, p=.000), liver function levels AST (5.47 U/L, p=.04), ALT (13.64 U/L, p=.000), total cholesterol, pTC -14.22. Conclusion : Based on the results of this study, the obesity management program will be able to maximize the effects of obesity control if exercise programs and psychotherapy are combined.

• 품질경영학회지
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• 제34권4호
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• pp.22-32
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• 2006

In these days, most of Korean industries advocates and utilizes Six Sigma as an integrated innovation tool for all their business and manufacturing processes. Six Sigma is known to bring more financial and managerial achievements than other innovation methods and tools. However, such successes are not always guaranteed. To adopt and implement Six Sigma successfully, it is necessary to grasp and understand essential characteristics of Six Sigma and then identify suitable elements and complements in consideration of vision, strategies, capability, circumstance and environment of the company. Step by step implementation plan may be built based on those ingredients. This study is to find out key ingredients (KIs) of Six Sigma. Potential ingredients selected from previous studies of success factors and ingredients of Six Sigma and TQM, and criteria of quality awards like MBNQA, EFQM, Deming prize and Korean National Quality Awards (KNQA) are classified into 11 categories based on experts' opinion and affinity analysis: management leadership, belt system, training, six sigma system, compensation, organization, corporate culture, customer focused, project selection, management of project results, and managerial achievements. Irrelevant or ineffective potential ingredients are discarded using factor analysis for the questionnaires answered by champions, MBB's and BB's of 90 Korean companies that have more than 3 years experience of Six Sigma. Also from the factor analysis, 3 factors are derived for each categories respectively except the managerial achievement category. Those 11 categories and 30 factors are defined as KIs of Six Sigma. This study also reveals that there is difference according to enterprise size, type of business, and implementation time in terms of KI's, and prioritizes KI's that an enterprise to pursue Six Sigma successfully should consider according to its characteristics.

• 한국정밀공학회지
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• 제22권10호
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• pp.174-185
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• 2005

This paper presents the design, fabrication, and testing results of a dual stage actuator system for a fine positioning of magnetic heads in magnetic disk drives. A novel rotary microactuator which is electrostatically driven and utilized as a secondary actuator was designed. The stator and rotor electrodes in the microactuator was revised to have the optimal shapes and hence produces much higher rotational torque compared with the conventional comb-shape electrodes. The microactuators were successfully fabricated using SoG(silicon on glass) processing technology, which is known as being cost-effective. The fabricated microactuator has the structural thickness of $45{\mu}m$ with the gap width of approximately $3{\mu}m$. The dynamic characteristic of microactuator/slider assembly was investigated, and its natural frequency and DC gain were measured to be 3.4kHz and 32nm/V, respectively. The microactuator/slider assembly was integrated into a HDD model V10 of Samsung Electronics Co. and a dual servo algorithm was tested to explore the tracking performance of dual stage actuator system where the LDV signals instead of magnetic head signals were used. Experimental results indicate that this system achieves the tracking accuracy of 30nm. This value corresponds to a track density of 85,000 track per inch(TPI), which is about 3 times greater than that of current hard disk drives.