• 제목/요약/키워드: chain

검색결과 14,374건 처리시간 0.038초

고하중용 버킷 롤러체인 시스템의 다물체 동역학 해석 및 내구성 연구 (Study on Multibody Dynamic Analysis and Durability of Heavy Load Bucket Roller Chain System)

  • 김창욱;박진철;이동우;송정일
    • 한국정밀공학회지
    • /
    • 제33권11호
    • /
    • pp.919-925
    • /
    • 2016
  • In this study, multibody dynamic and mechanical analyses were conducted for the structure of roller chain bucket elevator system. The fatigue life of the roller chain elevator system was determined under static and fatigue loadings. Results of multibody dynamic analysis suggested that the maximum contact force occurred at the drive sprocket engagement point with the roller chain due to maximum tension. Fatigue analysis results suggest that the high load roller chain system is durable and safe because its life time is more than 700,000 cycles, close to its designed value (1,000,000 cycle). However, the contact portion of plate and pin needed a safety factor. The dynamic analysis of the heavy load roller chain was conducted with a multibody dynamic analysis program. The results obtained in this study can be utilized for dynamic analysis of roller chain systems in all industries.

The Role of Market Orientation and Organizational Innovativeness in Enhancing the Supply Chain Agility of Korean Apparel Firms

  • Yoon, Taeyoung;Koh, Ae-Ran;Jin, Byoungho
    • 한국의류학회지
    • /
    • 제38권5호
    • /
    • pp.718-732
    • /
    • 2014
  • This study investigates the effects of two organizational variables (market orientation and organizational innovativeness) and the interaction between these two variables on supply chain agility as well as examines the moderating effect of 1) firm size and 2) the extent of global sourcing. Employing a web-based e-mail survey method, the study issued 1,320 questionnaires to South Korea apparel manufacturing companies; data from 147 completed surveys were analyzed. Market orientation, organizational innovativeness, and the interaction between the two variables positively affect supply chain agility. Firm size and global sourcing do not have any significant moderating effects on the relationship between organizational characteristics and supply chain agility. Companies with high market orientation and high organizational innovativeness have more agile supply chains than companies with only market orientation or organizational innovativeness. Firms need to effectively enhance market orientation and organizational innovativeness simultaneously to enhance supply chain agility. The lack of a moderating effect from firm size suggests that all companies should promote a greater degree of market orientation and organizational innovativeness to enhance supply chain agility regardless of firm size.

RFID-based Supply Chain Process Mining for Imported Beef

  • Kang, Yong-Shin;Lee, Kyounghun;Lee, Yong-Han;Chung, Ku-Young
    • 한국축산식품학회지
    • /
    • 제33권4호
    • /
    • pp.463-473
    • /
    • 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.

cDNA Cloning and Characterization of Type II Procollagen α1 Chain in the Skate Raja kenojei

  • Hwang Jae-Ho;Yokoyama Yoshihiro;Mizuta Shoshi;Yoshinaka Reiji
    • Fisheries and Aquatic Sciences
    • /
    • 제9권1호
    • /
    • pp.22-29
    • /
    • 2006
  • We determined the partial cDNA of Type II procollagen ${\alpha}1$[pro-${\alpha}1$(II)] chain (1802 bp) of the skate Raja kenojei, which codes 581 amino acid residues. The partial structure of the pro-${\alpha}1$(II) chain consisted of a part of triple helical region (309 residues) and a C-domain (272 residues). Comparing the chain to other vertebrates showed relatively low homology (about 50%) at the amino acid level. However, eight Cys residues in the C-domain of the skate pro-${\alpha}1$(II) chain were conserved in common with those of other vertebrates. The skate pro-${\alpha}1$ (II) chain mRNA was detected by RT-PCR of various tissues, but was undetected in tissues containing Type II collagen. The low homology and unexpected expression pattern suggest the presence of another mRNA variant of the skate pro-${\alpha}1$(II) chain. The present study is the first report of the primary structure of pro-${\alpha}1$(II) chain in an elasmobranch.

열린사슬 운동과 닫힌사슬운동시 내측광근과 대퇴이두근의 근활성도 차이 (Activation of Vastus Medialis and Biceps Femoris Muscle in Open and Closed Kinetic Chain Exercise)

  • 석창엽;이창렬;이문환
    • 대한예방한의학회지
    • /
    • 제12권3호
    • /
    • pp.115-128
    • /
    • 2008
  • Purpose : This study was performed to distinguish the muscle activation of vastus medialis and biceps femoris through open and closed kinetic chain exercise. Methods : 31 healthy male and female students in Daegu Health College were participated in this study. All subjects were conducted three types open and closed kinetic chain exercises to examine muscle activity during the last four seconds using the sEMG system. Collected EMG data were normalized using the maximal voluntary isometric contraction(MVIC). Results : MVIC of each muscle was showed significantly increased(p<0.5). In the case of open chain exercise, the type 3 exercise most increased than type 2 and 3 exercise in vastus medialis than biceps femoris muscle. The closed chain exercise presented type 6 exercise most increased than type 4 and 5 exercise in biceps femoris than vastus medialis. Conclusion : This study finally proved that muscle activity which maintains stability of knee differ from depending on the types of exercises. Therefore, the combination of the two chain exercises is believed to greatly contribute to increments in muscle activity.

  • PDF

An Integrated Approach to Measuring Supply Chain Performance

  • Theeranuphattana, Adisak;Tang, John C.S.;Khang, Do Ba
    • Industrial Engineering and Management Systems
    • /
    • 제11권1호
    • /
    • pp.54-69
    • /
    • 2012
  • Chan and Qi (SCM 8/3 (2003) 209) developed an innovative measurement method that aggregates performance measures in a supply chain into an overall performance index. The method is useful and makes a significant contribution to supply chain management. Nevertheless, it can be cumbersome in computation due to its highly complex algorithmic fuzzy model. In aggregating the performance information, weights used by Chan and Qi-which aim to address the imprecision of human judgments-are incompatible with weights in additive models. Furthermore, the default assumption of linearity of its scoring procedure could lead to an inaccurate assessment of the overall performance. This paper addresses these limitations by developing an alternative measurement that takes care of the above. This research integrates three different approaches to multiple criteria decision analysis (MCDA)-the multiattribute value theory (MAVT), the swing weighting method and the eigenvector procedure-to develop a comprehensive assessment of supply chain performance. One case study is presented to demonstrate the measurement of the proposed method. The performance model used in the case study relies on the Supply Chain Operations Reference (SCOR) model level 1. With this measurement method, supply chain managers can easily benchmark the performance of the whole system, and then analyze the effectiveness and efficiency of the supply chain.

공모된 체인 절단 공격으로부터 QCRT를 이용한 이동 에이전트의 보호 기법 (A Security Scheme of Mobile Agent using QCRT from Colluded Truncation Attacks)

  • 정창렬;김광오;송진국;이성근
    • 한국정보통신학회논문지
    • /
    • 제15권2호
    • /
    • pp.382-388
    • /
    • 2011
  • 본 논문에서는 프로로밍 에이전트의 데이터의 안전한 수행을 위해 악의적인 요인들에 의해 발생될 수 있는 절단공격으로부터 안전한 실행을 보장한다. 또한 기존의 체인관계보다 확장성을 개선한 쿼리 트리체인 관계(QCRT:query chain relationship tree)구조를 형성함으로써 악의적인 요소를 효과적으로 검출 할 수 있다. 또한 체인 관계 구조를 에이전트의 여정에 따라 형성되는 구조로 체크함으로써 에이전트의 체인관계를 확장하였다. 단면적인 체인관계의 확장으로 기존의 취약한 요소들을 보완하여 이동 에이전트의 절단공격으로부터 실행 보장을 하였다.

A Case Study on Engineering Failure Analysis of Link Chain

  • Kim, Tae-Gu;Lee, Seong-Beom;Lee, Hong-Chul
    • Safety and Health at Work
    • /
    • 제1권1호
    • /
    • pp.43-50
    • /
    • 2010
  • Objectives: The objective of this study was to investigate the effect of chain installation condition on stress distribution that could eventually cause disastrous failure from sudden deformation and geometric rupture. Methods: Fractographic method used for the failed chain indicates that over-stress was considered as the root cause of failure. 3D modeling and finite element analysis for the chain, used in a crane hook, were performed with a three-dimensional interactive application program, CATIA, commercial finite element analysis and computational fluid dynamic software, ANSYS. Results: The results showed that the state of stress was changed depending on the initial position of the chain that was installed in the hook. Especially, the magnitude of the stress was strongly affected by the bending forces, which are 2.5 times greater (under the simulation condition currently investigated) than that from the plain tensile load. Also, it was noted that the change of load state is strongly related to the failure of parts. The chain can hold an ultimate load of about 8 tons with only the tensile load acting on it. Conclusion: The conclusions of this research clearly showed that a reduction of the loss from similar incidents can be achieved when an operator properly handles the installation of the chain.

When VMI with Consignment Brings Benefit to Supply Chain Members?

  • RYU, Chungsuk
    • 산경연구논집
    • /
    • 제12권5호
    • /
    • pp.7-16
    • /
    • 2021
  • Purpose: This study intends to examine how VMI with consignment performs over time and find out its on-going impacts on the individual supply chain member's achievement. Research design, data, and methodology: This study formulates the mathematical model that represents two-stage supply chain system. By analyzing the numerical examples, this study compares VMI with consignment with the traditional system. Results: VMI with consignment eventually makes higher supply chain profit than the traditional system, even though it's early performance is poor. The influence of VMI with consignment on the performance of the supply chain member is distinct depending on the individual member and time. The consignment may not be helpful to increase the system profit, but it reduces the manufacturer's burden of costs. Conclusions: VMI with consignment improves the supply chain performance after all, and it still takes times until its benefit becomes fully realized. To be a successful collaboration program, VMI with consignment requires a carefully designed incentive scheme that provides the timely compensation to the individual supply chain members. This study also finds out that the consignment contract of this collaboration program plays a role of financially supporting the manufacturer at the early stage of its implementation.

Whole-cell Biotransformation of Chlorella Oil Hydrolysates into Medium Chain Fatty Acids

  • Seo, Joo-Hyun;Min, Won-Ki;Lee, Jung-Hoo;Lee, Sun-Mee;Lee, Choul-Gyun;Park, Jin-Byung
    • 한국해양바이오학회지
    • /
    • 제10권2호
    • /
    • pp.44-52
    • /
    • 2018
  • A synthetic pathway, which consisted of fatty acid double bond hydratase, alcohol dehydrogenase, and Baeyer-Villiger monooxygenase, was applied to Chlorella oil to produce ester fatty acids, which can be hydrolyzed into medium chain fatty acids. Since linoleic acid is a major fatty acid constituent of Chlorella oil, a fatty acid double bond hydratase from Lactobacillus acidophilus NBRC13951, which is able to convert linoleic acid into 13-hydroxyoctadec-9-enoic acid, was used. Recombinant Escherichia coli expressing the fatty acid double bond hydratase from L. acidophilus NBRC13951 successfully transformed linoleic acid in Chlorella oil hydrolysates into 13-hydroxyoctadec-9-enoic acid with approximately 60% conversion yield. 13-Hydroxyoctadec-9-enoic acid was further converted into ester fatty acids by the recombinant E. coli expressing a long chain secondary alcohol dehydrogenase and a Baeyer-Villiger monooxygenase. The resulting ester fatty acids were then hydrolyzed into medium chain fatty acids by a lipase. Overall, industrially relevant medium chain fatty acids were produced from Chlorella oil hydrolysates. Thereby, this study may contribute to biosynthesis of medium chain fatty acids from microalgae oils as well as long chain fatty acids.