• Title/Summary/Keyword: u-SCM

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A Study on the Residual Stress and Microstructure of Autofrettaged SCM440 High Strength Steel (자긴가공된 SCM440 고강도강의 잔류응력 및 미세구조 분석에 관한 연구)

  • Kim, J.H.;Shim, W.S.;Lee, Y.S.;Cha, K.U.;Hong, S.K.
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.311-316
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    • 2008
  • Thick-walled cylinders, such as a cannon or nuclear reactor, are autofrettaged to induce advantageous residual stresses into pressure vessels and to increase operating pressure and the fatigue lifetimes. As the autofrettage level increases, the magnitude of compressive residual stress at the bore also increases. The purpose of the present paper is to predict the accurate residual stress of SCM440 high strength steel using the Kendall model which was adopted by ASME Code. Hydraulic pressure process was applied and thick-walled cylinders were autofrettaged up to 30% overstrain levels. Electro polishing was performed to get more accurate data. Residual stresses were measured by X-ray diffraction method. The autofrettaged surface which was plastically deformed analyzed using a scanning electron microscope(SEM). Although there were some differences in measured residual stress and numerical, there is a tendency to agree.

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Development of Supply Chain Management Simulator (SCM 시뮬레이터 개발)

  • Lim, Seok Jin;Mo, Chang-U
    • Proceedings of the Safety Management and Science Conference
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    • 2013.04a
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    • pp.355-365
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    • 2013
  • Many manufacturing industries need more efficient organization since the customer expects a greater response to orders Due to this increased expectation, a supply chain management (SCM) has become one of the most important methods of competitive advantage in business today. This study has developed a simulator for the supply chain management problem. The simulator designed to help determine considering to the capacities and the costs of production and distribution facilities. The simulator developed using commercial simulation tool ARENA and the results of computational experiments for a simple example were given and discussed to validate the developed simulator. The simulator can be used to decide an realistic production-distribution planning in the area.

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Sorption of $UO^{2+}_2$ onto Goethite and Kaolinite: Mechanistic Modeling Approach

  • Jinho Jung;Lee, Jae-Kwang;Cho, Young-Hwan;Keum, Dong-Kwon;Hahn, Pil-Soo
    • Nuclear Engineering and Technology
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    • v.31 no.2
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    • pp.182-191
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    • 1999
  • The sorption of UO$_{2}$$^{2+}$ onto goethite and kaolinite under various experimental conditions was successfully interpreted using surface complexation modeling (SCM). The SCM approach used in this work is the triple-layer model (TLM) in which weakly bonded ions are modeled as outer-sphere (ion-pair) complexes and strongly bonded ions as inner-sphere (surface coordination) complexes. The change of ionic strength did not affect the U(VI) sorption onto goethite, thus the formation of inner-sphere surface complexes, (FeO)$_2$UO$_2$ and (FeO)$_2$(UO$_2$)$_3$OH$_{5}$ was assumed to simulate the effects of ionic strength and goethite concentration. On the other hand, the U(VI) sorption onto kaolinite showed ionic strength dependence, thus the formation of AlO-UO$_{2}$$^{2+}$(outer-sphere complex) and SiO(UO$_2$)$_3$OH$_{5}$ (inner-sphere complex) was assumed to simulate the experimental data. In the presence of carbonates, the sorption of U(VI) onto kaolinite decreased in the weakly alkaline pH range. This was well simulated assuming the formation of a outer-sphere surface complex, A1OH$^{2+}$- (UO$_2$)$_2$CO$_3$OH$_3$. Since SCM approach uses thermodynamic data such as surface complexation constants, it is more predictive than empirical modeling approach in which conditional values such as partition coefficient are used. used.

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Dynamic Reconfigurability in the Fractal-based Supply Chain Management (fSCM) (Fractal 기반 공급망 관리에 있어서의 동적 재구성력)

  • Ryu, Gwang-Yeol;Lee, Seok-U;Choe, Heon-Jong;Jeong, Mu-Yeong
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2004.05a
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    • pp.454-457
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    • 2004
  • The high degree of uncertainty in customer demands forces companies of today to equip with a flexible and adaptable structural organization. It also has an influence on the configuration of the company's supply chains, since the members in supply chains are dependent to the goods customers need. If a company can not come up with the customers' requirements and their level of satisfaction, the competitiveness of the company will be weaken in the market places. To meet such conditions, therefore, reconfiguration of supply chains should be considered as an important factor in a complex, dynamic, and fluctuating market environment. In this paper, therefore, we have adapted a fractal concept to SCM to facilitate reconfiguration of supply chains. To do so, we have first introduce fractal-based SCM, referred to as fSCM. Then, we have described definitions of the reconfigurability in supply chains and the methodology of Dynamic Restructuring Process (DRP) in supply chains including specific strategies and constraints. An exemplary model will also be briefly illustrated to demonstrate how supply chains conduct DRP autonomously.

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Characteristics of the Abdominal and Neck Flexor Muscles of Children with Cerebral Palsy

  • Choi, Sung-Jin;Bang, Dae-Hyouk;So, Hyun-Jung;Shin, Won-Seob
    • The Journal of Korean Physical Therapy
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    • v.26 no.6
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    • pp.453-458
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    • 2014
  • Purpose: The purpose of this study was to compare the activities of the abdominal and neck flexor muscles of children with and without cerebral palsy (CP) while lifting the head in a supine position. Methods: The subjects were eight children with CP and eight children without the disease. The activities of the external abdominal oblique (EO), internal abdominal oblique (IO), rectus abdominis (RA), sternocleidomastoid (SCM), and RA/SCM muscles were collected by surface electromyography (EMG) when the children lifted their heads. A Mann-Whitney U test was used to compare the activity of each muscle during the head-lifting exercise. Statistical significance was accepted at p<0.05. Results: The activities of the EO, IO, and RA, and RA/SCM muscles differed significantly between the children with and without CP, but there was no significant between-group difference in the activity of the SCM muscle. Conclusion: These findings suggest that the abdominal muscles are not employed as much in the activities of children with CP compared to those without the disease. Additionally, those with CP were more dependent on the neck flexor muscle during the head-lifting exercise in a supine position.

A Study on the Development of the Web-based u-WMS using RFID (RFID를 활용한 웹기반 u-창고관리시스템 개발에 대한 연구)

  • Lee, Gwang-Su;Park, Je-Won;Choe, Yun-Jeong;Lee, Hui-Nam;Lee, Chang-Ho
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2005.05a
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    • pp.360-366
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    • 2005
  • This paper deals with the S/W development of web-based warehouse management system using ubiquitous RFID(Radio Frequency Identification). This S/W System supports the realtime inventory management and collaborative operations of relational companies in SCM. We expect to decrease the logistic cost and to upgrade the status of WMS and competitive power of company.

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Legality of R&D Subsidies and Its Policy Framework under the World Trading System: The Case of Civil Aircraft Disputes

  • Shin, Wonkyu;Lee, Wonhee
    • STI Policy Review
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    • v.4 no.1
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    • pp.27-53
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    • 2013
  • Technology research and development (R&D) expenditures have increased as most countries recognize that technological innovation is a significant factor for continued economic growth. R&D subsidies by governmental entities were permitted in accordance with the Subsidy and Countervailing Measure (SCM) Agreement under the World Trade Organization (WTO) system. However, according to Article 31 of the SCM Agreement the provision for R&D subsidies have been terminated as of January 2000 and legal disputes over R&D subsidies are likely to increase. The aircraft industry has been the only industry where R&D subsidies have become an issue under the WTO. This paper examines international trade disputes within the aircraft industry in regards to measures by Canada and bilateral disputes between the U.S. and the European Communities (EC). In these cases, various R&D subsidies on civil aircraft are found to be inconsistent with WTO rules. This study summarizes the WTO decisions on various R&D subsidies disputed in the aircraft cases and examines the type of R&D subsidies found to be inconsistent (or consistent) with the WTO to provide guidelines for current and future R&D subsidy policies in high-tech industries. The Canada-Aircraft case indicates that R&D subsidies directly targeted towards near market R&D projects with a high export potential will likely be in violation of current WTO rules. Furthermore, findings from the EC-Aircraft and the U.S.-Aircraft cases suggest that the forms (or the methods) of R&D subsidy distribution were not a sufficient condition for the WTO ruling; instead, what ultimately mattered was whether and specifically to whom the benefits of the R&D subsidies are conferred by the government entities.

Business Models for SongTan Ubiquitous City (송탄 u-City의 성공적인 비즈니스 모델)

  • Jang, Hee-Seon;Cho, Kee-Seong
    • The Journal of the Korea Contents Association
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    • v.7 no.11
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    • pp.223-231
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    • 2007
  • This paper presents the main business models in ubiquitous city (u-City), the future city strategically integrated with the ubiquitous computing technology. Based on the concept of u-City, the chief services related to the u-City that has been actively developed are analysed, and then the best main four business models (u-Tour, u-ITS, u-SCM and B2B) for SongTan city are presented. The four business models are selected from making an analysis for the present situation of the tour industries, industrial complex, traditional market in SongTan. With the business models, the strategies to realize the active business transactions, high revenues, high value-adding industries, self-sufficient business through the construction of u-City are also presented. Finally, the promoting plans for local autonomy party, citizen party and consortium of industries/universities/researches to give an comfortable u-Life to citizen in SongTan are described.

RFID-based Supply Chain Process Mining for Imported Beef

  • Kang, Yong-Shin;Lee, Kyounghun;Lee, Yong-Han;Chung, Ku-Young
    • Food Science of Animal Resources
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    • v.33 no.4
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    • pp.463-473
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    • 2013
  • Through the development of efficient data collecting technologies like RFID, and inter-enterprise collaboration platforms such as web services, companies which participate in supply chains can acquire visibility over the whole supply chain, and can make decisions to optimize the overall supply chain networks and processes, based on the extracted knowledge from historical data collected by the visibility system. Although not currently active, the MeatWatch system has been developed, and is used in part for this purpose, in the imported beef distribution network in Korea. However, the imported beef distribution network is too complicated to analyze its various aspects using ordinary process analysis approaches. In this paper, we suggest a novel approach, called RFID-based supply chain process mining, to automatically discover and analyze the overall supply chain processes from the distributed RFID event data, without any prior knowledge. The proposed approach was implemented and validated, by using a case study of the imported beef distribution network in Korea. Specifically we demonstrated that the proposed approach can be successfully applied to discover supply chain networks from the distributed event data, to simplify the supply chain networks, and to analyze anomaly of the distribution networks. Such novel process mining functionalities can reinforce the capability of traceability services like MeatWatch in the future.

Computation of High Temperature Friction Coefficient of SCM435 Steel (SCM435 강의 고온마찰계수 계산)

  • Sung, J.U.;Cho, S.H.;Lee, H.J.;Lee, Y.
    • Transactions of Materials Processing
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    • v.20 no.3
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    • pp.243-249
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    • 2011
  • In this study, an approach designed to compute high temperature friction coefficients for SCM 435 steel through a pilot hot rolling test and a finite element analysis, is proposed. Single pass pilot hot flat rolling tests with reduction ratios varying from 20 to 40% were carried out at temperatures ranging from 900 to $1200^{\circ}C$. In the proposed approach, the friction coefficient is calculated by comparing the measured strip spread and the roll force with the simulation results. This study showed that the temperature and reduction ratio had a significant influence on the friction coefficient. As both material temperature and reduction ratio become higher, the friction coefficient increases monotonically. This finding is not in agreement with the Ekelund model, which is widely used in the analysis of the hot rolling process. In the present work, the friction coefficient at a reduction ratio of 40% was found to be 1.2 times greater than that at a reduction of 30%. This higher friction coefficient means that an increment of the roll thrust force is expected at the next stand. Therefore, a roll pass designer must understand this phenomenon in order to adjust the reduction ratio at the stands while keeping the driving power, the roll housing structure and the work roll strength within the allowable range.