• Title/Summary/Keyword: Complex parts

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On the Development of Reference Guidelines for Self-evaluation of Organization's Systems Engineering and Project Management Capability (조직의 SEPMC 자체 평가에 유용한 참조기준 개발)

  • Choi, Young Gil;Lee, Jae Chon
    • Journal of the Korean Society of Systems Engineering
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    • v.8 no.2
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    • pp.27-36
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    • 2012
  • In modern systems, the operational capability of the system to the user needs is expanding rapidly to accommodate the size of the system, functionality, and interfaces are becoming increasingly complex. Accordingly, the systematic practice of project management and systems engineering in the system development process, as an important element in successful systems development is recognized. EIA/ANSI 632, ISO/IEC15288, the leading international standard for systems engineering and is the leading international standard on project management PMBOK. CMMI is also contains information about the activities of project management and systems engineering and worldwide basis to assess the maturity of an organization's ability to develop system being used. But CMMI model is too complex of structure and there are many overlap parts of contents. So there are many problems for members of organization understanding all of CMMI model, applying organization and, achieving improvement activity. In this study, through the analysis and integration between the model and the related standard coverage activities essential for successful systems development in organizations that require systems engineering and project management capabilities(SEPMC) for self-assessment and continuous improvement activities to provide useful reference guideline.

A Compiler Based Rule Engine for Developing Changeable Component (가변적인 컴포넌트 개발을 위한 컴파일러 방식의 룰 엔진)

  • Lee, Yong-Hwan
    • Journal of KIISE:Computing Practices and Letters
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    • v.12 no.6
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    • pp.379-385
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    • 2006
  • To improve reusability and adaptation of variable components, rule-based component development has been used. Rule engines usually need additional script languages for rule expression and have difficulty in expressing complex business rules. In this paper, we propose a compiler-based rule engine for rich rule expression and improving performance. This rule engine uses Java programming language to express conditions and action parts of rules and that it can easily express complex business rules. It creates and executes condition and action objects at run time. In view of Performance, the rule engine is better than a script based rule engine. According to our experiments, our compiler-based nile engine shows 2.5 times better performance that script-based JSR 94 rule engine.

MICROSTRUCTURAL CHARACTERISTICS OF HOT FORGED AL 6061 ALLOY

  • Kwon Y.-N.;Lee Y.-S.;Lee J.-H.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2003.10b
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    • pp.55-58
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    • 2003
  • Many researches have been already done on the issues of high temperature deformation and the microstructural evolution. The information has been very useful for the plasticity industry, especially successful for the extrusion. However, the parts made with forging usually have a complex shape. It is difficult to control the distribution of the variables like strain, strain rate and temperature rise due to the working heat during a hot-forging process. Consequently, the microstructural variation could be occurred depending on the plastic deformation history that the forged part would get during a hot forging. In the present study, the microstructural characteristic of a hot-forged 6061 aluminum alloy has been discussed on the aspect of grain size evolution. A forging of 6061 aluminum alloy has been carried out for a complex shape with a dimensional variation. Also, finite element analysis has been done to understand how the deformation variables such as strain, strain rate give an influence on the microstructure of a hot forged aluminum product.

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Development of the Optimized Angle Head for Internal Shape Machining Using Five-Axis Machine Tool (5축가공기를 활용한 내면 형상 가공용 최적 앵글헤드의 개발)

  • Hwang, Jong-Dae;Kim, Jae-Hyun;Cho, Young-Tae;Jung, Yoon-Gyo;Ko, Hae-Ju
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.14 no.1
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    • pp.123-129
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    • 2015
  • In general, recent critical studies of five-axis machine have tended to center on the question of effective machining to realize complex shape parts. However, the hydrostatic bearing and journal bearing, both of which are involved in the complex process of dividing the processing of internal precision-shape machining, must be optimized. Although the angle head is designed to machine the internal shape as it approaches the inner diameter of the work piece, research on the angle head in five-axis machining has received only minimal attention in domestic industries. In this study, an angle head which is optimized for effective internal shape machining is developed. In pursuit of this purpose, 3D and 2D designs of the angle head for five-axis machining are devised. Reliability is secured through static performance tests and machining accuracy evaluations of the angle head in keeping with the machining accuracy standard of 0.2mm for hydrostatic bearings.

A Proteomic Screen for Presynaptic Terminal N-type Calcium Channel (CaV2.2) Binding Partners

  • Khanna, Rajesh;Zougman, Alexandre;Stanley, Elise F.
    • BMB Reports
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    • v.40 no.3
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    • pp.302-314
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    • 2007
  • N type calcium channels (CaV2.2) play a key role in the gating of transmitter release at presynaptic nerve terminals. These channels are generally regarded as parts of a multimolecular complex that can modulate their open probability and ensure their location near the vesicle docking and fusion sites. However, the proteins that comprise this component remain poorly characterized. We have carried out the first open screen of presynaptic CaV2.2 complex members by an antibody-mediated capture of the channel from purified rat brain synaptosome lysate followed by mass spectroscopy. 589 unique peptides resulted in a high confidence match of 104 total proteins and 40 synaptosome proteome proteins. This screen identified several known CaV2.2 interacting proteins including syntaxin 1, VAMP, protein phosphatase 2A, $G_{o\alpha}$, G$\beta$ and spectrin and also a number of novel proteins, including clathrin, adaptin, dynamin, dynein, NSF and actin. The unexpected proteins were classified within a number of functional classes that include exocytosis, endocytosis, cytoplasmic matrix, modulators, chaperones, and cell-signaling molecules and this list was contrasted to previous reports that catalogue the synaptosome proteome. The failure to detect any postsynaptic density proteins suggests that the channel itself does not exhibit stable trans-synaptic attachments. Our results suggest that the channel is anchored to a cytoplasmic matrix related to the previously described particle web.

Design Enhancements for Automotive Integrated Shell Structures (차량 복합판형부품의 설계개선 기법들)

  • Lee, Hyeong-Il;Seo, Hyeon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.5 s.176
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    • pp.1103-1114
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    • 2000
  • Recent attempt to enhance the safety against collision reshaped the simple shell structures into the integrated complex shell structures. Moreover, due to various regulations continuously tightened for environment protection, weight reduction of automobiles becomes an increasingly important issue. Auto parts lightening is mainly accomplished by more reasonable design, adoption of lighter materials and miniaturization of the auto bodies. Focusing on the locally enhanced design approach among the above three ways, we here attempt to develop a patching optimization method, and also to determine the thicknesses of an integrated shell structure, both bringing a specified amount of stress relaxation. We first select a cross member as a patching optimization model. Based on the finite element stress calculations, we relieve the stress of cross member by patching in two ways-nonuniform thickness patching and optimized uniform thickness patching, the latter of which is more effective in a practical point of view for the preset amount of stress relaxation. Selecting a box type subframe as another finite element analysis model, we then determine the thickness of each part by axiomatic design approach for a preset amount of stress relaxation. The patching methodology and the axiomatic approach adopted in this work can be applied to the other complex shell structures such as center member and lower control arm.

Dynamic characteristics and wind-induced vibration coefficients of purlin-sheet roofs

  • Zhang, Yingying;Song, Xiaoguang;Zhang, Qilin
    • Steel and Composite Structures
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    • v.22 no.5
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    • pp.1039-1054
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    • 2016
  • This paper presents the dynamic characteristics analysis of the purlin-sheet roofs by the random vibration theories. Results show that the natural vibration frequency of the purlin-sheet roof is low, while the frequencies and mode distributions are very intensive. The random vibration theory should be used for the dynamic characteristics of the roof structures due to complex vibration response. Among the first 20th vibration modes, the first vibration mode is mainly the deformations of purlins, while the rest modes are the overall deformations of the roof. In the following 30th modes, it mainly performs unilateral local deformations of the roof. The frequency distribution of the first 20th modes varies significantly while those of the following 30th modes are relatively sensitive. For different parts, the contributions of vibration modes on the vibration response are different. For the part far from the roof ridge, only considering the first 5th modes can reflect the wind-induced vibration response. For the part near the ridge, at least the first 12 modes should be considered, due to complex vibration response. The wind vibration coefficients of the upwind side are slightly higher than that of the leeward side. Finally, the corresponding wind vibration coefficient for the purlin-sheet roof is proposed.

Automated Visual Inspection System of PCB using CAD Information (CAD 정보를 잉용한 PCB 자동 시각 검사 시스템)

  • Park, Byung-Joon;Hahn, Kwang-Soo
    • Journal of Korea Multimedia Society
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    • v.12 no.3
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    • pp.397-408
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    • 2009
  • Image training is a very important yet difficult state for automated visual inspection using computers. Because the size of parts for the recently produced PCB (Printed Circuit Board) becomes smaller and circuit patterns gradually become more complex, a difficult and complex training process is becoming a big problem within an industry where development cycle for new products is short and various products must be inspected. This research produced a reference image by using CAD (Gerber) file which becomes a standard for PCB automatic visual inspection. Reference image from a Gerber file guarantees PCB patterns with no defects. Through system implementation and experimentation, Gerber file is used in order to propose a plan which allows an easy training process for PCB automatic visual inspection system.

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Central Nervous Pathway for Heating Pain and Acupuncture Stimulation: Localization of Processing with Functional MR Imaging of the Brain -Preliminary Experience

  • Yoon, Moon-Hyun;Choe, Bo-Young;Choi, Gi-Soon;Yoon, Sung-Ik;Woo, Dong-Cheol
    • Proceedings of the Korean Society of Medical Physics Conference
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    • 2005.04a
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    • pp.89-92
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    • 2005
  • The effects of acupuncture are complex and how it works is not entirely clear. Research suggests that the needling process, and other modalities used in acupuncture, may produce their complex effects on a wide variety of ways in the brain and the body. For example, it is theorized that stimulated nerve fibers transmit signals to the spinal cord and brain, thus activating parts of what is called the central nervous system. The spinal cord and brain then release certain hormones responsible for making us feel better overall and, more specifically, feel less pain. In fact, a study using images of the brain confirmed that acupuncture increases our pain threshold, which may explain its ability to produce long-term pain relief. Also, acupuncture may increase blood circulation and body temperature. It may also affect white blood cell activity (responsible for our immune function).

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Measurement Method of Complex Dynamic Viscoelastic Material Properties (점탄성 재료의 복소수 동특성 측정방법)

  • Lee, In-Won;An, Nam-Hyun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.33 no.5
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    • pp.489-495
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    • 2009
  • A novel technique to measuret of viscoelastic properties of polymers is proposed to investigate complex Poisson's ratio as a function of frequency. The forced vibration responses for the samples under the normal and the shear deformation are to be measured with varying load masses. The measured data were used to obtain the viscoelastic properties of the material based on an accurate 2D numerical deformation model of the sample. The 2D model enabled us to exclude data correction by the empirical form factor used in 1D model. Comprehensive measurements of viscoelastic properties of two slightly varied silicone RTV rubber ($Silastic^{(R)}$ S2) compositions were performed. Standard composition (90% PDMS polymer + 10% catalyst) and modified composition (92.5% polymer + 7.5% catalyst) were tested in temperature range from $30^{\circ}C$ to $70^{\circ}C$. Shear modulus, modulus of elasticity, loss factor, and both the real and the imaginary parts of the Poisson's ratio were determined for frequencies from 50 to 400Hz in the linear deformation regime (at relative deformations $10^{-4}{\sim}10^{-3}$).