• Title/Summary/Keyword: working mechanism

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A Study on Building Web Services for Implementing Real Time Enterprise

  • Lee, Jung-Min
    • 한국경영정보학회:학술대회논문집
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    • 2007.11a
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    • pp.377-382
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    • 2007
  • To transform the enterprise system into the 'Real Time Enterprise' with respect to IT, I suggest the conceptual application model which is composed of pieces(components) extracted from different packaged applications working in a heterogeneous environment based on the 'business activity' in other words, business services provided by internal (inter-enterprise) and external (extended enterprise) application to support a business activity within in an enterprise and the design mechanism focusing service tier which acts as intermediate tier within application architecture.

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A Study on the Change of Suface Characteristics by plane suface Rolling(l) (평면 Rolling에 의한 표면특성 변화에 관한 연구(l))

  • 김희남
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1997.04a
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    • pp.1-5
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    • 1997
  • The plane surface rolling, one of the plastic working process, good surface condition due to increase of surface roughness and hardness. It is well known that mechanism of surface rolling depends upon rolling conditions such as rolling speed, contact pressure, step length of rolling, the shape of roller and mechanical properties of material. In this study, the optimal value of the above parameter on the surface roughness were investigated by using the rolling tool with NACHI 6000ZZ ball bearing outer races on machine structure carbon steel[SM45C]

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Finite Element Analysis on the Sealing Mechanism of U-Cup Seals (U-컵 시일의 밀봉기구에 관한 유한요소해석)

  • 최준업;전인기;김희준;김청균
    • Tribology and Lubricants
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    • v.10 no.3
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    • pp.12-17
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    • 1994
  • Minimum clearance between the U-cup seal groove of a piston and a cylinder bore to ensure against extrusion of the U-cup ring and leakage of working fluids is an important design parameter for a seal designer in hydraulic cylinder applications. Therefore, typical U-cup seal of a hydraulic actuator has been analyzed as a function of a sealing gap using the nonlinear FEM software MARC. In this study, the useful design data were presented as a function of the sealing gap and the sealed hydraulic pressure.

Piezoelectric Nanogenerators: Energy Harvesting Technology (압전 나노발전기: 에너지 수확 기술)

  • Shin, Dong-Myeong;Hwang, Yoon-Hwae
    • Vacuum Magazine
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    • v.3 no.2
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    • pp.17-20
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    • 2016
  • Piezoelectric nanogenerators are energy harvesting device to convert a mechanical energy into an electric energy using nanostructured piezoelectric materials. This review summarizes works to date on piezoelectric nanogenerators, starting with a basic theory of piezoelectricity and working mechanism, and moving through the reports of numerous nanogenerators using nanorod arrays, flexible substrates and alternative materials. A sufficient power generated from nanogenerators suggests feasible applications for either power supplies or strain sensors of highly integratedl nano devices. Further development of nanogenerators holds promise for the development of self-powered implantable and wearable electronics.

Actuating Characteristics of Electrostatic Micro-motors

  • Kim, Young-Cheol;Kim, Byung-Ok
    • 연구논문집
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    • s.33
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    • pp.53-65
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    • 2003
  • Electrostatic micro-motors can be divided into three classes: (i) salient type side drive motor, (ii) radial gap type wobble motor, (iii) axial gap type wobble motor. The working mechanism, torque evaluation, fabrication, and operational characteristics of each micro motors are compared. It is proved that axial gap type wobble motor has the bigger generating torque than that of the other type. The gear ratio of wobble motors increases the driving torque at the cost of a decreasing angular speed and decreases the friction because of the rolling motion instead of sliding at the bearing. Techniques for characterizing micro-motors performance are presented.

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Design of A Cross Working Mechanism for Hierarchical Security Policy (계층적 보안 정책에서의 Cross 연동 메커니즘)

  • 이지인;엄남경;이상호
    • Proceedings of the Korean Information Science Society Conference
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    • 2001.04a
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    • pp.787-789
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    • 2001
  • 인터넷은 전세계를 대상으로 구축된 네트워크로서 개방형 구조의 프로토콜을 사용하므로 대부분의 호스트 컴퓨터 시스템들은 정보보안에 취약한 상태이다. 이와 같은 보안 취약성으로 인해 상용화 서비스에 대한 교환 정보의 수정, 검색, 파괴 등의 역기능이 발생하고 있다. 이 논문에서는 기존의 보안 방식 정책으로는 인터넷 보안의 역기능에 대한 완벽한 대책이 될 수 없으므로 이에 따른 보안정책 크로스 연동 메커니즘을 설계하여, 기존의 방식과 비교 분석해서 앞으로의 차세대 인터넷에 적합한 연동메커니즘을 제안하고자 한다.

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Main Cause of the Interference between Visual Search and Spatial Working Memory Task (시각 탐색과 공간적 작업기억간 상호 간섭의 원인)

  • Ahn Jae-Won;Kim Min-Shik
    • Korean Journal of Cognitive Science
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    • v.16 no.3
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    • pp.155-174
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    • 2005
  • Oh and Kim (2004) and Woodman and Lurk (2004) demonstrated that spatial working memory (SWM) load Interfered concurrent visual search and that search process also impaired the maintenance of spatial information implying that visual search and SWM task both require access to the same limited-capacity mechanism. Two obvious possibilities have been suggested about what this shared limited-capacity mechanism is: common demand for attention to the locations where the items f9r the two tasks were presented (spatial attention load hypothesis), and common use of working memory to maintain a record of locations have been processed(SWM load hypothesis). To test these two hypothetical explanations, Experiment 1 replicated the mutual interference between visual search and SWM task in spite of difference of procedure with preceding researches; possible areas where the items for two tasks were presented were not separated. In Experiment 2, we presented the items for visual search either in the same quadrants where the items for SWM task had appeared (same-location rendition) or in the different quadrants (different-location condition). As a result, search efficiency was more impaired in the different-location condition than in the same-location condition. The memory accuracy was worse in the different-location rendition than in the same-location rendition. Overall results of study indicate that the mutual interference between SWM and visual search might be related to the overload of spatial attention, but not to that of SWM.

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Symbiotic Dynamic Memory Balancing for Virtual Machines in Smart TV Systems

  • Kim, Junghoon;Kim, Taehun;Min, Changwoo;Jun, Hyung Kook;Lee, Soo Hyung;Kim, Won-Tae;Eom, Young Ik
    • ETRI Journal
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    • v.36 no.5
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    • pp.741-751
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    • 2014
  • Smart TV is expected to bring cloud services based on virtualization technologies to the home environment with hardware and software support. Although most physical resources can be shared among virtual machines (VMs) using a time sharing approach, allocating the proper amount of memory to VMs is still challenging. In this paper, we propose a novel mechanism to dynamically balance the memory allocation among VMs in virtualized Smart TV systems. In contrast to previous studies, where a virtual machine monitor (VMM) is solely responsible for estimating the working set size, our mechanism is symbiotic. Each VM periodically reports its memory usage pattern to the VMM. The VMM then predicts the future memory demand of each VM and rebalances the memory allocation among the VMs when necessary. Experimental results show that our mechanism improves performance by up to 18.28 times and reduces expensive memory swapping by up to 99.73% with negligible overheads (0.05% on average).

Internal Based Cooperative Network Model for University's Internship Abroad with Cooperation of International NGOs: Cooperative Case of CBMC (대학의 해외인턴쉽을 위한 인터넷에 기초한 국제NGO 협력 Network Model - CBMC와 협력사례를 중심으로)

  • Kang Young-Moo
    • The Journal of Information Systems
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    • v.15 no.3
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    • pp.159-174
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    • 2006
  • Employment rate of graduating students has been one of the most important issues at universities. Recently interest on internship abroad has been increased significantly due to globalization of the society In particular, central and local governments have developed policies and encouraged university students to participate in internships abroad. However, activities and resources for internships abroad are very limited to a few organizations. This paper investigated the current status of internship in the U.S. and Korea. Then, this paper analyzed differences in demand and supply of the internship and matching mechanism of the internship between the U.S. and Korea. From the results of those analyses, this paper developed an international network model which can help effective and efficient increase in the demand and supply of the internship as well as the internship matching mechanism in Korea. This network model utilizes international NGOs in order to develop internationally cooperative environment. This model provides mechanism for (1) effectively identifying intern applicants who like to work abroad and evaluating thent (2) effectively identifying new internship positions and evaluating companies which plan to hire interns, (3) efficiently matching demand for and supply of internship by identifying appropriate candidates, (4) monitoring companies for their quality of working conditions and interns for their qualities of work This model for internship has been applied for a NGO which is International CBMC (Christian Businessman Committee International)

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Radio Resource Metric Estimation (RRME) Mechanism for Multimedia Service Applications based on a CDMA Communication System

  • Lee Yeon-Woo;Cho Kwang-Moon;Hur Kyeong
    • International Journal of Contents
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    • v.2 no.2
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    • pp.10-16
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    • 2006
  • In this paper, we propose a predictive resource metric region (RMR) based radio resource metric estimation (RRME) mechanism, which utilizes a resource metric mapping function (RMMF), both of which permit efficient inter-working between the physical layer and higher layers for envisaging multimedia service applications over a CDMA communication system platform. The RMR can provide the acceptable resource region where QoS and acceptable link quality can be guaranteed with an achievable resource margin to be utilized in terms of capacity margin, the degree of confidence (DCL) of user, second-order statistics of Eb/Io. With predicted capacity margin and variance, DCL can deliver decision parameters with which an adaptive QoS based admission control can perform well taking capacity and resource availability into account in a dynamic and predictive manner. Combined with advanced techniques such as adaptive modulation or rate control and power control, the proposed mechanism can adjust the conventional stringent link quality information efficiently, and deliver accurate information of the resource availability. Thus, these can guarantee the maximization of resource utilization of multimedia service applications.

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