• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.8
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• pp.748-757
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• 2015

MIMO systems utilizing multiple antenna transmission and reception is one of the key technologies to enhance the capacity of 5G wireless communications. In order to obtain an appropriate performance evaluation of MIMO techniques, the usage of wireless channel model reflecting spatial channel characteristics is required, such as the 3-dimensional spatial channel model(3D SCM) proposed by 3GPP TR36.873 documentation. In this paper, we implement and verify the channel simulation environment based on 3D SCM, to present and compare the characteristics of UMi and UMa environments. We also apply MIMO transmission to the UMa scenario to investigate the channel correlation among antenna elements with different array distances and to identify the corresponding throughput changes. By evaluating the channel power correlations for randomly distributed users within the sector for different horizontal and vertical antenna distances, we present the statistical characteristics which determine the transmission performance under the SCM environment.

• Journal of the Korean Society for Heat Treatment
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• v.24 no.1
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• pp.10-15
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• 2011

Recently, renewable energy sources such as wind turbine, solar cell are interested in preventing global warming which is caused by the consumption of fossil fuel. SCM440(H) and SNCM439 have been used in the major components of the wind turbine gear because of excellent mechanical properties. In the present study, the heat treated mechanical properties of SCM440(H) and SNCM439 with 150 mm diameter were compared with those with 25 mm diameter which is generally accepted material for structural application. Heat treated SCM440(H) showed better mechanical properties such as tensile strength, hardness and impact absorbed energy compared with those in SNCM439. Hardenss value between as-quenched and as-quenched followed by tempering showed big difference in SNCM439, however the difference in SCM440(H) was relatively small. Heat treated mechanical properties of the alloys with 25 mm diameter were more uniform value than those with 150 mm diameter.

• Proceedings of the Korea Multimedia Society Conference
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• 2012.05a
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• pp.172-176
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• 2012

섬유산업은 다품종 소량생산 및 납기단축을 요구함으로써 기업간 실시간 정보협업 (재고유무, 공정진행 등)이 필수 요소로 대두되고 있으며, 이를 해결하기 위하여 섬유산업 특성을 반영한 효율적 정보 협업시스템 개발 및 보급을 목적으로 SCM 정보시스템 구축을 위한 비즈니스 프로세스를 모델링하였다. 또한 기업에서 현재 사용 중인 ERP 외 신규 SCM 구축에 따른 기존 사용자 거부반응을 최소화하기 위하여 기존 사용 중인 ERP시스템에 부착하여 정보협업이 가능한 표준 게이트웨이 모듈과 자체 시스템이 없는 중소 영세기업을 위한 Saas기반SCM으로 분류하여 비즈니스 프로세스를 설계 및 프로토타입을 구현하였으며, 기업 데이터 연계를 위한 거래문서정보 표준화 도출을 통하여 수평적 정보협업 업무통합 비즈니스 프로세스를 설계하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.133-134
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• 2012

• Journal of the Korea Society for Simulation
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• v.24 no.4
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• pp.163-170
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• 2015

This research is to focus on the method of moving line optimization in Agricultural Industry, especially Garak Wholesale Market Modernization Project, by using simulation tool. As everybody knew, it's very difficult to apply the SCM operation rules in Agricultural Industry, because the standardization system in Agricultural Industry was not completed. The five flow management factors, vehicle moving line management, customer moving line Management, Logistics Device Moving Line Management, Working Person Moving Line Management, Product display moving line management, are needed to be optimized on the basis of standardization rules, and to achieve this will be the good infrastructure to make the Agricultural SCM system. It's very different between the SCM structure of manufacturing industry and logistics industry and the SCM structure of Agricultural Industry, because the SCM in manufacturing is occur in the basis of flow management, on the contrary, the SCM of Agricultural Industry is on the basis of activity management. For these reason, this study is the first approach to apply the simulation method in the part of moving line optimization in Agricultural SCM, and in near future, This study will help all designers and operators to apply the simulation work in the part of agricultural SCM, and we hope that next advanced study will continue by using this study.

• The KIPS Transactions:PartD
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• v.8D no.3
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• pp.257-264
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• 2001

We developed a SIFG (Slice-based Information Graph), which modelled the information flow on program on the basis of the information flow of data tokens on data slices. Then we defied a SCM (Slice-based complexity measure), which measured the program complexity by measuring the complexity of information flow on SIFG. SCM satisfied the necessary properties for complexity measure proposed by Briand et al. SCM could measure not only the control and data flow on program but also the physical size of program unlike the existing measures.

• The Journal of Society for e-Business Studies
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• v.9 no.3
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• pp.1-16
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• 2004

The purpose of this study is to explore the nature of supply chain partnership, and to find the factors influencing the supply chain partnership success. For this, relationship commitment and trust were used as the basic components of the supply chain partnership. Also we identified strategic fit, interdependence, compatibility, and communication as determinants of supply chain partnership. Based on the statistical analysis of the sample of Korean corporations, it was found that relationship commitment and trust were shown to be significant factors influencing the supply chain partnership success. In addition, the findings reveal that strategic fit, interdependence, compatibility, and communication will facilitate supply chain partnership. More specifically, strategic fit and interdependence have a significant positive influence on relationship commitment. Also, compatibility and communication have a significant positive influence on trust. There result, in short, supported the importance of supply chain partnership for the successful SCM.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.10
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• pp.873-878
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• 2016

SCM415 steel for the control valve undergoes wear because of continuous movement between the valve and valve case. The wear of the valve interrupts the performance of the valve, and decreases the service life. In this study, wear characteristics of the as-received and carburized SCM415 steels are evaluated. The wear tests are conducted for various temperatures and loads using a reciprocating wear tester. From these results, wear loss, specific wear rate, and coefficient of friction are analyzed. The wear mechanism was analyzed by SEM. The interaction effects between loads and temperatures on wear loss are determined for analysis of variance using MINITAB.

• Ocean and Polar Research
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• v.34 no.4
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• pp.413-430
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• 2012

To understand the scales of the spatial distribution and temporal duration of the subsurface chlorophyll-a maximum (SCM) observed in the Ulleung Basin of the East Sea, we analyzed physical and chemical data collected during the East Asian Seas Time-series-I (EAST-I) program. The SCM layer occurred at several observation lines from the Korea Strait to $37.9^{\circ}N$ in the Ulleung Basin during August of 2008 and 2011. At each observation line, the SCM layer extended from the coast to about 200 km off the coast. The SCM layer was observed between 30 and 40 m depth in the Ulleung Basin as well as in the northwestern Japan Basin along $132.3^{\circ}E$ from $38^{\circ}N$ to $42.3^{\circ}N$ during July 2009, and was observed around 50 m depth in the northeastern Japan Basin ($135-140^{\circ}E$ and $40-45^{\circ}N$) during July 2010. From these observed features, we hypothesize that the SCM layer observed in the Ulleung Basin may exist in most of the East Sea and may last for at least half-year (from the early May to late October). The nutrient supply mechanism for prolonged the SCM layer in the East Sea was not known, but it may be closely related to the horizontal advection of the nutrient rich and low oxygen waters observed in the Korea Strait between a 50 m depth to near the bottom. The prolonged development of the SCM layer in the Ulleung Basin may result in high primary production and would also be responsible for the high organic carbon content observed in the surface sediment of the region.

• Korean Journal of Materials Research
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• v.8 no.8
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• pp.707-713
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• 1998

The influence of plasma carburizing process on the surface hardness of SCM415 low-alloy steel (0.15% C) was investigated under the various process conditions of gas composition. gas pressure, plasma current density. temperature and time. The effective case depth was found to depend on the amount of methan gas containing carbon. thus the deepest case depth and the uniform hardeness were obtained with the 100% methan gas. The case depth increased with the plasma current density. The effective plasma carburizing temperature of SCM415 steel was found to be higher than 85$0^{\circ}C$, and the case depth was proportional to the square root of carburizing time under the same current density. The bending fatigue strength of the plasma carburized specimen is' higher than those of as- received specimen or reheat-quenched specimen.