• 제목/요약/키워드: Link transformation

검색결과 82건 처리시간 0.02초

Massless Links with External Forces and Bushing Effect for Multibody Dynamic Analysis

  • Sohn, Jeong-Hyun;Yoo, Wan-Suk;Hong, Keum-Shik;Kim, Kwang-Suk
    • Journal of Mechanical Science and Technology
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    • 제16권6호
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    • pp.810-818
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    • 2002
  • When the contribution of lightweight components to the total energy of a system is small, tole inertia effects are sometimes ignored by replacing them to massless links. For example, a revolute-spherical massless link generates two kinematic constraint equations between adjacent bodies and allows four relative degrees of freedom. In this paper, to implement a massless link systematically in a computer program using the velocity transformation technique, the velocity transformation matrix of massless links is derived and numerically implemented. The velocity transformation matrix for a revolute-spherical massless link and a revolute-universal massless link are appeared as a 6$\times$4 matrix and a 6$\times$3 matrix, respectively. A massless link model in a suspension composite joint transmitting external forces is also developed and the numerical efficiency of the proposed model is compared to a conventional multibody model. For a massless link transmitting external forces, forces acting on links are resolved and transmitted to the attached points with a quasi-static assumption. Numerical examples are presented to verify the formulation.

Goodness of Link Tests for Binary Response Data

  • Yeo, In-Kwon
    • Communications for Statistical Applications and Methods
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    • 제8권2호
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    • pp.357-366
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    • 2001
  • The present paper develops a method to check the propriety of link functions for binary data. In order to parameterize a certain type of goodness of the link, a family of link functions indexed by a shape parameter is proposed. I first investigate the maximum likelihood estimation of the shape parameter as well as regression parameters and then derive their large sample behaviors of the estimators. A score test is considered to evaluate the goodness of the current link function. For illustration, I employ two families of power transformations, the modulus transformation by John and Draper (1980) and the extended power transformation by Yeo and Johnson (2000), which are appropriate to detect symmetric and asymmetric inadequacy of the selected link function. respectively.

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형체력에 따른 사출성형기 플렉스링크의 특성 분석 (Characteristics Analysis of Flex Link according to Mold Clamping Force in Injection Molding Machine)

  • 정현석;유중학
    • 한국정밀공학회지
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    • 제31권2호
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    • pp.165-170
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    • 2014
  • Reproducibility of injection molding machines are studied at the study of this time. We applied computer aided engineering program so it could generate clamping force, about 1,500 kN, to the nozzle center part of flex link in tie-bar and at this time, we made sure condition of stress distribution and transformation quantity in flex link. The result of computer aided engineering transformation quantity was confirmed that transformation of top area was 247~257 kN and bottom areas was 273~279 kN and also was confirmed that the stresses are distributed in a range of 57~750 $N/mm^2$ from top to the bottom of the surface. This time we could confirm the condition of transformation quantity and stress distribution by enforcing the previously used structure analysis of flex link. And we utilized the reference data to establish important point of section for non destructive test overhaul.

The Distribution of Research Framework on Exsheetlink Module Development for Accounting Education

  • Nor Sa'adah, JAMALUDDIN;Rohaila, YUSOF;Noor Lela, AHMAD
    • 유통과학연구
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    • 제21권2호
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    • pp.45-52
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    • 2023
  • Purpose: The Malaysia Education Blueprint is primarily concerned with the transformation of students' minds through the curriculum offered at the school level (2013-2025). Diversity in the application of teaching and learning methods is one means of achieving the transformation of students' minds through the Secondary School Standard Curriculum. Consequently, the production of ExSheetLink's Module for Accounting Education is the primary outcome of this study, which had three objectives: the need for ExSheetLink's Module in the process of producing financial statements for Accounting Students in secondary school to the Accounting Teacher; and the design of ExSheetLink's Module that meets the entire process in the production of financial statements for Accounting Students in secondary school based on the Documents Curriculum and the Accounting Students' needs. Research design, data and methodology: This study outlines the research framework for module development in accordance with the Design and Development Research Method, which combines multiple research techniques (Mixed Method). Results: The development of ExSheetLink's Module is completed and can be used for the level of effectiveness purposes. Conclusion: The transformation of Accounting Students' minds is a success thanks to the ExSheetLink Module. Researchers also suggested that all Malaysian Secondary School accounting students test the ExSheetLink Module.

Research of Adaptive Transformation Method Based on Webpage Semantic Features for Small-Screen Terminals

  • Li, Hao;Liu, Qingtang;Hu, Min;Zhu, Xiaoliang
    • ETRI Journal
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    • 제35권5호
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    • pp.900-910
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    • 2013
  • Small-screen mobile terminals have difficulty accessing existing Web resources designed for large-screen devices. This paper presents an adaptive transformation method based on webpage semantic features to solve this problem. According to the text density and link density features of the webpages, the webpages are divided into two types: index and content. Our method uses an index-based webpage transformation algorithm and a content-based webpage transformation algorithm. Experiment results demonstrate that our adaptive transformation method is not dependent on specific software and webpage templates, and it is capable of enhancing Web content adaptation on small-screen terminals.

Digital Orientation for Emerging Multinationals and the Location Strategies in Internationalization: The Chinese Experience

  • Xinyue Zhang;Bo Kyung Kim;Jooyoung Kwak
    • 아태비즈니스연구
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    • 제14권3호
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    • pp.1-16
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    • 2023
  • Purpose Despite the ongoing digital transformation, it is not clear whether emerging market firms follow their manufacturing FDI path in the emerging digital industries. This paper examines how digital orientation affects the location strategies in internationalization and how the existing innovation capacities moderate the link between digital orientation and the location strategies. Design/methodology/approach This study chooses the Chinese setting for research design because digital transformation is already prevalent in the society and the cases of outward expansion are salient among the emerging markets. It uses the panel dataset of 976 Chinese listed firms that consists of 6,648 observations spanning from 2007 to 2017. Ordinary least square regression is used for the statistical approach with a one-year lag in the model. Findings Digital orientation increases a likelihood of emerging multinationals' entries in developed countries, and a high level of innovative capacities strengthens the link. Two groups seem to prefer entries in developed countries: firms with a high level of digital orientation with a high level of innovative capacities and firms with a low level of digital orientation, if with a low level of innovative capacities. The former reflects the context of digital transformation and the latter hints at the tax avoidance or interests in real estate. Research implications or originality While emerging multinationals are known to prefer entries in developing countries for capacity arbitrage, our results forecast that their FDI strategies may have a drastic change as digital transformation deepens.

반복형태식을 이용한 多物體系의 動力學的 해석 (Dynamic analysis of a multibody system using recursive-formula)

  • 신상훈;유완석
    • 대한기계학회논문집
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    • 제12권6호
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    • pp.1265-1272
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    • 1988
  • 본 연구에서는 속도변환을 이용하여 기본체(base body)가 움직이는 경우에 대 한 일반적인 운동방정식을 유도하고, 이를 적절히 변형시킴으로써 로봇분야에서 이미 유도된 식과 비슷한 반복형태의 식을 얻을 수 있음을 보임으로써, 기계의 동력학 분야 에서 사용하고 있는 속도변환의 방법이 기본체가 고정되어 있는 경우가 대부분인 로봇 분야에서도 적용될 수 있음을 보이고자 한다. 또한 유도된 반복형태식을 이용하여 개방연쇄계(open-loop system)로 이루어진 기계시스템의 동력학 시뮬레이션에 적합한 알고리즘을 만들고 자동차를 예제로 택하여 유도된 방법의 타당성과 효율성을 검토하 였다.

모델변환에 의한 고양이 로봇 시스템의 점핑제어 (Jumping Control of a Cat Robotic System by Model Transformation)

  • 서진호;;김상봉
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 하계학술대회 논문집 D
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    • pp.2427-2429
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    • 2002
  • 본 논문에서는, 지붕위로 뛰어오르기 위하여 벽의 반동을 이용하는 고양이의 운동상태를 흉내내어 수직의 방향으로 운동하는 고양이 로봇 시스템을 연구한다. 또한 이러한 로봇 시스템의 3-link 부분시스템의 운동은 slider-link에서 구속되어지고, 또한 singular자세를 쉽게 피할 수 있는 운동계획방법(motion planning method)을 제안한다. 제안되어진 연구결과는 수직동작에 대한 메카니즘에 유용한 방법이고 이론적 개념, 모델링, 그리고 제어를 논의한다. 마지막으로, 모의실험을 통한 결과로서 제안되어진 방법의 유용성을 설명한다.

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Homogeneous Transformation Matrix의 곱셈을 위한 병렬구조 프로세서의 설계 (A Parallel-Architecture Processor Design for the Fast Multiplication of Homogeneous Transformation Matrices)

  • 권두올;정태상
    • 대한전기학회논문지:시스템및제어부문D
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    • 제54권12호
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    • pp.723-731
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    • 2005
  • The $4{\times}4$ homogeneous transformation matrix is a compact representation of orientation and position of an object in robotics and computer graphics. A coordinate transformation is accomplished through the successive multiplications of homogeneous matrices, each of which represents the orientation and position of each corresponding link. Thus, for real time control applications in robotics or animation in computer graphics, the fast multiplication of homogeneous matrices is quite demanding. In this paper, a parallel-architecture vector processor is designed for this purpose. The processor has several key features. For the accuracy of computation for real application, the operands of the processors are floating point numbers based on the IEEE Standard 754. For the parallelism and reduction of hardware redundancy, the processor takes column vectors of homogeneous matrices as multiplication unit. To further improve the throughput, the processor structure and its control is based on a pipe-lined structure. Since the designed processor can be used as a special purpose coprocessor in robotics and computer graphics, additionally to special matrix/matrix or matrix/vector multiplication, several other useful instructions for various transformation algorithms are included for wide application of the new design. The suggested instruction set will serve as standard in future processor design for Robotics and Computer Graphics. The design is verified using FPGA implementation. Also a comparative performance improvement of the proposed design is studied compared to a uni-processor approach for possibilities of its real time application.

온라인 좌표 역변환 알고리듬의 개발과 이의 실험적 수행 (Development of on-line inverse kinematic algorithm and its experimental implementation)

  • 오준호;박서욱;이두현
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국내학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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    • pp.16-20
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    • 1988
  • This paper presents a new algorithm for solving the inverse kinematics in real-time applications. The end-tip movement of each link can be resolved into the basic resolution unit, .DELTA.l, which depends on link length, reduction ratio and resolution of the incremental encoder attached to the joint. When x- and y-axis projection of the end-tip movement are expressed in .DELTA.l unit, projectional increments .DELTA.x and .DELTA.y become -1, 0 or I by truncation. By using the incremental computation with these ternary value and some simple logic rules, a coordinate transformation can be realized. Through this approach, it should be noted that the floating-point arithmetic and the manipulation of trigonometric functions are completely eliminated. This paper demonstrates the proposed method in a parallelogram linkage type, two-link arm.

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