• Title/Summary/Keyword: multi-assembly

검색결과 361건 처리시간 0.027초

DNC 시스템 개발 (Development of a Ddistributed Numerical Control System)

  • Kim, S.H.;S.W.;S.B.;J.H.
    • 한국정밀공학회지
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    • 제12권12호
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    • pp.19-29
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    • 1995
  • The basic technology for a production system represented by design, machining, assembly, and inspection, is machining technology such as CNC machine tools. etc. Direct Numerical Control, that effeciently manages NC programs is developing into Distributed Numerical Control that increases the utilization of the machining cell. It has the ability of monitoring and control, in real time, for CNC and periperial equipment. In this study, we develop a Distributed Numerical Control system that has real time and multitasking operation capability for the machining cell with various CNC's. With the consideration of economy, generalization and extension, the system is interfaced with CNC machine tools and periperial device using RS-485 network and RS-232C communication methods.

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The Heterochromatin Protein 1 (HP1) Family: Put Away a Bias toward HP1

  • Kwon, So Hee;Workman, Jerry L.
    • Molecules and Cells
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    • 제26권3호
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    • pp.217-227
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    • 2008
  • Heterochromatin protein 1 (HP1) was first described in Drosophila melanogaster as a heterochromatin associated protein with dose-dependent effect on gene silencing. The HP1 family is evolutionarily highly conserved and there are multiple members within the same species. The multi-functionality of HP1 reflects its ability to interact with diverse nuclear proteins, ranging from histones and transcriptional co-repressors to cohesion and DNA replication factors. As its name suggests, HP1 is well-known as a silencing protein found at pericentromeres and telomeres. In contrast to previous views that heterochromatin is transcriptionally inactive; noncoding RNAs transcribed from heterochromatic DNA repeats regulates the assembly and function of heterochromatin ranging from fission yeast to animals. Moreover, more recent progress has shed light on the paradoxical properties of HP1 in the nucleus and has revealed, unexpectedly, its existence in the euchromatin. Therefore, HP1 proteins might participate in both transcription repression in heterochromatin and euchromatin.

여자유도 액츄에이터를 이용한 능동RCC 장치의 개발 (Development of Adaptive RCC Mechanism Using Double-Actuator Units)

  • 임혁진;김병상;강병덕;송재복;박신석
    • 로봇학회논문지
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    • 제2권2호
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    • pp.168-177
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    • 2007
  • In a number of fields, robots are being used for two purposes: efficiency and safety. Most robots, however, have single-actuator mechanism for each joint, where the tasks are performed with high stiffness. High stiffness causes undesired problems to the environment and robots. This study proposes redundant actuator mechanism as an alternative idea to cope with these problems. In this paper, Double-Actuator Unit (DAU) is implemented at each joint for applications of multi-link manipulators. The DAU is composed of two motors: the positioning actuator and the stiffness modulator, which enables independent control of positioning and compliance. A three-link manipulator with DAUs enables adaptive control of RCC. By modulating the joint stiffness of the manipulator and controlling the position of RCC, we can significantly reduce contact force during assembly tasks and surgical procedures.

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유압시스템 롤-오프 청정도의 이론적 고찰 및 트랙터에의 응용 (A Theoretical Investigation of Roll-Off Cleanliness for Hydraulic System and Application to a Tractor)

  • 이재천
    • 한국자동차공학회논문집
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    • 제8권5호
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    • pp.207-215
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    • 2000
  • This study theoretically investigated the roll-off cleanliness operation to eliminate the built-in contaminants which are primarily the result of manufacturing and assembly procedures first. A rigorous analytical examination of the cleaning process associated with hydraulic systems was performed by developing the general filtration process equations. The sloughing process by which built-in contaminant is entrained in the system fluid was examined during the development of a general analytical expression for sloughing rate. This sloughing rate expression in conjunction with the filtration process equations have lead to a relationship rate expression in conjunction with the filtration process equations have lead to a relationship which describes the flushing and clean-up operation for the hydraulic systems. The effects of the primary roll-off cleanliness factors was discussed and illustrated on the figures. Then, the analytical results was shown to be usefully applied into the design of roll-off flushing equipment for the hydraulic system of a tractor.

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AEGIS: AN ADVANCED LATTICE PHYSICS CODE FOR LIGHT WATER REACTOR ANALYSES

  • Yamamoto, Akio;Endo, Tomohiro;Tabuchi, Masato;Sugimura, Naoki;Ushio, Tadashi;Mori, Masaaki;Tatsumi, Masahiro;Ohoka, Yasunori
    • Nuclear Engineering and Technology
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    • 제42권5호
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    • pp.500-519
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    • 2010
  • AEGIS is a lattice physics code incorporating the latest advances in lattice physics computation, innovative calculation models and efficient numerical algorithms and is mainly used for light water reactor analyses. Though the primary objective of the AEGIS code is the preparation of a cross section set for SCOPE2 that is a three-dimensional pin-by-pin core analysis code, the AEGIS code can handle not only a fuel assembly but also multi-assemblies and a whole core geometry in two-dimensional geometry. The present paper summarizes the major calculation models and part of the verification/validation efforts related to the AEGIS code.

Database and knowledge-base for supporting distributed intelligent product design

  • Nguyen Congdu;Ha Sungdo
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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    • pp.87-91
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    • 2004
  • This research presents distributed database and knowledge-base modeling approach for intelligent product design system. The product design information in this study is described by a collection of rules and design knowledge that are utilized according to the product development procedures. In this work, a network-based architecture has been developed to enable dispersed designers to simultaneously accomplish remote design tasks. A client/server communication diagram has also been proposed to facilitate consistent primary information modeling for multi-user access and reuse of designed results. An intelligent product design system has been studied with the concepts of distributed database and network-based architecture in order to support concurrent engineering design and automatic design part assembly. The system provides the capability of composing new designs from proper design elements stored in the database and knowledge-base. The distributed intelligent product design is applied to the design of an automobile part as an example.

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수동 Compliance가 능동적 Compliance제어의 안정도에 미치는 영향 (A Stability Effect of Passive Compliance on Active Compliance Control)

  • Chung, Tae-Sang
    • 대한전기학회논문지
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    • 제39권1호
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    • pp.92-106
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    • 1990
  • Active compliance is often used in the control of robot manipulators for the implementation of complex tasks such as assembly, multi-finger fine motion, legged-vehicle adaptive control,etc. This technique balances the interactive force between the manipulator tip and its working environment with its position and velocity errors to achieve the operation of a damped spring. This paper investigates the effecft of passive compliance on system stability with regard to force feedback implementation for actively compliant motion. Usually it is understood that accurate position control require a stiff system. However, theoretical examination of control experiments on a legged suspension vehicle suggests that, if the control includes discrete-time force feedback, some passive compliance is necessssary at the legs of the vehicle for system stability. This can be an important factor to bl considered in manipulator design and control. A theoretical analysis, numerical simulation, and experimental result, confirming the above conclusion, are introduced in this paper.

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안드로이드 기반 공개키 암호를 위한 곱셈기 구현 및 분석 (Implementation and Analysis of Multi-Precision Multiplication for Public Key Cryptography Based on Android Platform)

  • 서화정;김호원
    • 한국통신학회논문지
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    • 제37C권10호
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    • pp.940-948
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    • 2012
  • 안드로이드 프로그램은 JAVA SDK로 제작되어 가상머신(virtual machine) 기반으로 동작한다. 따라서 기존의 C 언어에 비해 프로그램 작성은 편리해 졌지만 동작 속도는 떨어지는 단점이 있다. 이러한 단점을 보완하기 위해 안드로이드 상에서 C언어, 어셈블리 언어의 사용이 가능한 안드로이드 NDK가 제안되어 보다 효율적인 프로그램 작성이 가능하게 되었다. 이와 더불어 ARM에서 제공하는 NEON기능을 사용하면 벡터연산을 통해 성능을 향상 시킬 수 있다. 본 논문에서는 NDK의 효용성에 대해 알아보며 NEON기능을 이용한 향상된 곱셈구조를 제안한다.

Multi-step Reactions on Microchip Platform Using Nitrocellulose Membrane Reactor

  • Park, Sung-Soo;Joo, Hwang-Soo;Cho, Seung-Il;Kim, Min-Su;Kim, Yong-Kweon;Kim, Byung-Gee
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제8권4호
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    • pp.257-262
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    • 2003
  • A straightforward and effective method is presented for immobilizing enzymes on a microchip platform without chemically modifying a micro-channel or technically microfabricating a column reactor and fluid channel network. The proposed method consists of three steps: the reconstitution of a nitrocellulose (NC) membrane on a plane substrate without a channel network, enzyme immobilization on the NC membrane, and the assembly of another substrate with a fabricated channel network. As a result, enzymes can be stably and efficiently immobilized on a microchip. To evaluate the proposed method, two kinds of enzymatic reaction are applied: a sequential two-step reaction by one enzyme, alkaline phosphatase, and a coupled reaction by two enzymes, glucose oxidase and peroxidase, for a glucose assay.

Phage Litmus: Biomimetic Virus-Based Colorimetric Sensors for Explosive Detection

  • 오진우
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.90.1-90.1
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    • 2013
  • Nature utilizes various of the colorization process. Some species of birds can express their mood of tempers by changing their collagen structures on skin. For example, turkey can change their skin color by expansion of the collagen structures, which are associated with the distinct color changes. Here, we developed bioinspired virus-based colorimetric sensors which can be genetically tuned for target molecule. Using M 13 bacteriophage, we fabricated responsive self-assembled color matrices composed of quasi-ordered fiber bundle structures. These virus matrices can exhibit color change by stimuli through fiber bundle structure modulation. Upon exposure of volatile organic compounds, the resulting multi-colored matrices exhibited distinct color changes with different ratios that can be recognized by the naked eyes. Using the directed evolutionary approaches, we genetically engineered the virus matrix to incorporate binding motif for explosive detection (i.e., trinitrotoluene (TNT)). Through utilizing a common handheld device (i.e., iPhone), we could distinguish TNT molecules down to 20 ppb in a selective manner. Our novel biomimetic virus colorimetric sensor can overcome current limitation for low response selectivity.

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