• Title/Summary/Keyword: 구조 메커니즘

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Behavioral Characteristics and Energy Dissipation Capacity of Short Coupling Beams with Various Reinforcement Layouts (다양한 배근상세를 갖는 짧은 연결보의 주기거동 특성과 에너지소산능력의 평가)

  • Eom, Tae-Sung;Park, Hong-Gun;Kang, Su-Min
    • Journal of the Korea Concrete Institute
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    • v.20 no.2
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    • pp.203-212
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    • 2008
  • The cyclic behavior and energy dissipation mechanism of short coupling beams with various reinforcement layouts were studied. For numerical analysis of coupling beams, nonlinear truss model was used. The results of numerical analysis showed that the coupling beams with conventional reinforcement layout showed pinched cyclic behavior without significant energy dissipation, whereas the coupling beams with diagonal reinforcement exhibited stable cyclic behavior without pinching. The energy dissipation of the coupling beams was developed mainly by diagonal reinforcing bars developing large plastic strains rather than concrete which is a brittle material Based on this result, simplified equations for evaluating the energy dissipation of coupling beams were developed. For verification, the predicted energy dissipation was compared with the test results. The results showed that the simplified equations can predict the energy dissipation of short coupling beams with shear span-to-depth ratio less than 1.25 with reasonable precision, addressing various design parameters such as reinforcement layout, shear span-to-depth ratio, and the magnitude of inelastic displacement. The proposed energy equations can be easily applied to performance-based seismic evaluation and design of reinforced concrete structures and members.

Exploring the Triple Helix Innovation System in the Dutch Food Cluster(Food Valley) (네덜란드 라흐닝언 식품산업 클리스터(푸드밸리)의 트리플 힐릭스 혁신체계)

  • Lee, Chul-Woo;Kim, Tae-Yeon;Lee, Jong-Ho
    • Journal of the Korean association of regional geographers
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    • v.15 no.5
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    • pp.554-571
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    • 2009
  • This paper explores the triple helix innovation system in Food Valley in the Netherlands which is considered one of the most innovative food clusters in the world. The triple helix approach has been so far little tackled in the literature on innovation system and cluster. However, tills approach can be a useful tool for understanding the dynamic characters and knowledge transfer mechanism of industrial cluster. On the basis of an in-depth case study, we argue that Food Valley has evolved through four circles of growth in the triple helix innovation system. From the mid-2000s onward, it is seen that Food Valley has been on the stabilized circle in the triple helix system of innovation. Centered upon Wageningen UR, local universities and research centers play a pivotal role in building the triple helix innovation system. To cope with radical changes in markets and technology since the late 1980s, local firms have made a great deal of effort to reinforce the university-industry partnership. On the other hand, government agencies have played a critical role for establishing institutional milieu that facilitate university-industry partnerships and local knowledge transfer and spillover.

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(Buffer Management for the Router-based Reliable Multicast) (라우터 기반의 신뢰적 멀티캐스트를 위한 버퍼 관리)

  • 박선옥;안상현
    • Journal of KIISE:Information Networking
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    • v.30 no.3
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    • pp.407-415
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    • 2003
  • As services requesting data transfer from a sender to a multiple number of receivers become popular, efficient group communication mechanisms like multicast get much attention. Since multicast is more efficient than unicast in terms of bandwidth usage and group management for group communication, many multicast protocols providing scalability and reliability have been proposed. Recently, router-supported reliable multicast protocols have been proposed because routers have the knowledge of the physical multicast tree structure and, in this scheme, repliers which retransmit lost packets are selected by routers. Repliers are selected dynamically based on the network situation, therefore, any receiver within a multicast group can become a replier Hence, all receivers within a group maintains a buffer for loss recovery within which received packets are stored. It is an overhead for all group receivers to store unnecessary packets. Therefore, in this paper, we propose a new scheme which reduces resource usage by discarding packets unnecessary for loss recovery from the receiver buffer. Our scheme performs the replier selection and the loss recovery of lost packets based on the LSM [1] model, and discards unnecessary packets determined by ACKs from erasers which represent local groups.

A Two-Step Call Admission Control Scheme using Priority Queue in Cellular Networks (셀룰러 이동망에서의 우선순위 큐 기반의 2단계 호 수락 제어 기법)

  • 김명일;김성조
    • Journal of KIISE:Information Networking
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    • v.30 no.4
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    • pp.461-473
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    • 2003
  • Multimedia applications are much more sensitive to QoS(Quality of Service) than text based ones due to their data continuity. In order to provide a fast moving MH(Mobil Host) using multimedia application with a consistent QoS,an efficient call admission mechanism is in need. This paper proposes the 2SCA(2-Step Call Admission) scheme based on cal admission scheme using pripority to guarantee the consistent QoS for mobile multimedia applications. A calls of MH are classified new calls, hand-off calls, and QoS upgrading calls. The 2SCA is composed of the basic call admission and advanced call admission; the former determines the call admission based on bandwidth available in each cell and the latter determines the call admission by applying DTT(Delay Tolerance Time), PQeueu(Priority Queue), and UpQueue(Upgrade Queue) algorithm according to the type of each call blocked at the basic call admission stage. In order to evaluate the performance of our mechanism, we measure the metrics such as the dropping probability of new calls, dropping probability of hand-off calls, and bandwidth utilization. The result shows that the performance of our mechanism is superior to that of existing mechanisms such as CSP(Complete Sharing Policy), GCP(Guard Channel Policy) and AGCP(Adaptive Guard Channel Policy).

A Study on Design of Smart Home Service Robot McBot II (스마트 홈 서비스 로봇 맥봇II의 설계에 관한 연구)

  • Kim, Seung-Woo;Kim, Hi-Jun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.4
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    • pp.1824-1832
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    • 2011
  • In this paper, a smart home service robot McBot II is newly developed in much more practical and intelligent system than McBot I which we had developed a few years ago. Thus far, vacuum-cleaners have lightened the burden of household chores but the operational labor that vacuum-cleaners entail has been very severe. Recently, a cleaning robot was commercialized to solve but it also was not successful because it still had the problem of mess-cleanup, which pertained to the clean-up of large trash and the arrangement of newspapers, clothes, etc. Hence, we develop a new home mess-cleanup robot McBot II to completely overcome this problem on real environments. The mechanical design and the basic control of McBot II, which performs mess-cleanup function etc. in house, is actually focused in this paper. McBot II is mechanically modeled in the same method that the human works in door by using the waist and the hands. The big-ranged vertical lift and the shoulder joints to be able to forward move are mechanically designed for the operating function as the human's waist when the robot works. The mobility of McBot II is designed in the holonomic mobile robot for the collision avoidance of obstacle and the high speed navigation on the small area in door. Finally, good performance of McBot II, which has been optimally desinged, is confirmed through the experimental results for the control of the robotic body, mobility, arms and hands in this paper.

Service Level Agreement Specification Model of Software and Its Mediation Mechanism for Cloud Service Broker (클라우드 서비스 브로커를 위한 소프트웨어의 서비스 수준 합의 명세 모델과 중개 방법)

  • Nam, Taewoo;Yeom, Keunhyuk
    • Journal of KIISE
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    • v.42 no.5
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    • pp.591-600
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    • 2015
  • SLA (Service Level Agreement) is an essential factor that must be guaranteed to provide a reliable and consistent service to user in cloud computing environment. Especially, a contract between user and service provider with SLA is important in an environment using a cloud service brokerage. The cloud computing is classified into IaaS, PaaS, and SaaS according to IT resources of the various cloud service. The existing SLA is difficult to reflect the quality factors of service, because it only considers factors about the physical Network environment and have no methodological approach. In this paper, we suggested a method to specify the quality characteristics of software and proposed a mechanism and structure that can exchange SLA specification between the service provider and consumer. We defined a meta-model for the SLA specification in the SaaS level, and quality requirements of the SaaS were described by the proposed specification language. Through case studies, we verified proposed specification language that can present a variety of software quality factors. By using the UDDI-based mediation process and architecture to interchange this specification, it is stored in the repository of quality specifications and exchanged during service binding time.

A Study on the Equations for Load Carrying Capacities of Concrete Filled tubular Square Column-to-Beam Connections with Combined Cross Diaphragm and Sleeves (복합십자형 CFT 기둥-보 접합부의 내력식에 관한 연구)

  • Choi, Sung Mo;Jung, Do Sub;Kim, Dae Joong;Kim, Jin Ho
    • Journal of Korean Society of Steel Construction
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    • v.17 no.4 s.77
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    • pp.419-429
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    • 2005
  • The objective of this study is to clarify the structural features of members consisting of a connection, as part of the previous study on the CFT column-to-beam tensile connection with a combined cross diaphragm. This connection has the following merits: it evenly distributes the stress on the beam flange and the diaphragm and reduces the stress concentration by improving the stress transfer route and restraining the abrupt deformation of the diaphragm. Finite element analysis was performed to find out the stress transfer through the sleeve, which is an important member of the connection with a combined cross diaphragm. The length and thickness of the sleeve were used as variables for the analysis. The analysis results showed that the length and thickness of the sleeve did not influence the capacity of the connection and played the role of a medium for the transfer of the stress from the diaphragm to the filled concrete. It was proposed that the appropriate length of the sleeve have the same value as the diameter of the sleeve and that the appropriate ratio of the sleeve diameter to the sleeve thickness be 20. Two equations for the evaluation of the load carrying the capacity of the connection were also proposed through the modification of the evaluation equation suggested in the previous study.

A Method for Protein Functional Flow Configuration and Validation (단백질 기능 흐름 모델 구성 및 평가 기법)

  • Jang, Woo-Hyuk;Jung, Suk-Hoon;Han, Dong-Soo
    • Journal of KIISE:Computing Practices and Letters
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    • v.15 no.4
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    • pp.284-288
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    • 2009
  • With explosively growing PPI databases, the computational approach for a prediction and configuration of PPI network has been a big stream in the bioinformatics area. Recent researches gradually consider physicochemical properties of proteins and support high resolution results with integration of experimental results. With regard to current research trend, it is very close future to complete a PPI network configuration of each organism. However, direct applying the PPI network to real field is complicated problem because PPI network is only a set of co-expressive proteins or gene products, and its network link means simple physical binding rather than in-depth knowledge of biological process. In this paper, we suggest a protein functional flow model which is a directed network based on a protein functions' relation of signaling transduction pathway. The vertex of the suggested model is a molecular function annotated by gene ontology, and the relations among the vertex are considered as edges. Thus, it is easy to trace a specific function's transition, and it can be a constraint to extract a meaningful sub-path from whole PPI network. To evaluate the model, 11 functional flow models of Homo sapiens were built from KEGG, and Cronbach's alpha values were measured (alpha=0.67). Among 1023 functional flows, 765 functional flows showed 0.6 or higher alpha values.

Reliability Analysis of The Mission-Critical Engagement Control Computer Using Active Sparing Redundancy (ASR 기법을 적용한 임무지향 교전통제 컴퓨터의 신뢰도 분석)

  • Shin, Jin-Beom;Kim, Sang-Ha
    • The KIPS Transactions:PartA
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    • v.15A no.6
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    • pp.309-316
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    • 2008
  • The mission-critical engagement control computer for air defense has to maintain its operation without any fault for a long mission time. The mission performed by large-scale and complex embedded software is extremely critical in terms of dependability and safety of computer system, and it is very important that engagement control computer has high reliability. The engagement control computer was implemented using four processors. The distributed computer composed of four processors quarantees the dependability and safety, and ASR fault-tolerant technique applied to each processor guarantees the reliability. In this paper, the mechanism and performance of ASR fault-tolerant technique are analysed. And MTBF, reliability, availability, and cost-effectiveness for ASR, DMR and TMR techniques applied to the engagement control computer are analysed. The mission-critical engagement control computer using software-based ASR fault-tolerant technique provides high reliability and fast recovery time at a low cost. The mission reliability of the engagement control computer using ASR technique in 4 processors board is almost same the reliability of the computer using TMR technique in 6 processors board. ASR technique is most suitable to the mission-critical engagement control computer.

The effect of Swd2's binding to Set1 on the dual functions of Swd2 in Saccharomyces cerevisiae (Saccharomyces cerevisiae의 Swd2와 Set1의 결합이 Swd2의 이중적인 기능에 미치는 영향)

  • Park, Shinae;Lee, Jung-Shin
    • Korean Journal of Microbiology
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    • v.53 no.4
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    • pp.286-291
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    • 2017
  • In eukaryotic cells, histone modification is an important mechanism to regulate the chromatin structure. The methylation of the fourth lysine on histone H3 (H3K4) by Set1 complex is one of the various well-known histone modifications. Set1 complex has seven subunits including Swd2, which is known to be important for H2B ubiquitination dependent on H3K4 methylation. Swd2 was reported to regulate Set1's methyltransferase activity by binding to near RNA recognition motif (RRM) domain of Set1 and to act as a component of CPF (Cleavage and Polyadenylation Factors) complex involved in RNA 3' end processing. According to the recent reports, two functions of Swd2 work independently of each other and the lethality of Swd2 knockout strain was known to be caused by its function as a component of CPF complex. In this study, we found that Swd2 could influence the Set1's stability as well as histone methyltransferase activity through the association with RRM domain of Set1. Also, we found that ${\Delta}swd2$ mutant bearing truncated-Set1, which cannot interact with Swd2, lost its lethality and grew normally. These results suggest that the dual functions of Swd2 in H3K4 methylation and RNA 3' end processing are not independent in Saccharomyces cerevisiae.