• Title/Summary/Keyword: action constraints

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A Representation of Engineering Change Objects and Their Integrity Constraints Using an Active Object-Oriented Database Model (능동형 객체지향적 데이터베이스 모텔을 이용한 설계변경 개체 및 제약조건의 표현)

  • 도남철
    • Journal of Information Technology Applications and Management
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    • v.10 no.1
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    • pp.111-125
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    • 2003
  • This paper proposes a product data model that can express and enforce integrity constraints on product structure during engineering changes (ECs). The model adopts and extends an active object-oriented database model in order to Integrate IC data and their integrity constraints. Tightly integrated with product structure, It will enable designers to maintain and exchange consistent EC data throughout the product life cycle. In order to properly support operations for ECs, the model provides the data, operations, and Event-Condition-Action rules for nested ECs and simultaneous EC applications to multiple options. in addition, the EC objects proposed In the model integrate the data and Integrity constraints into a unified repository. This repository enables designers to access all EC data and integrity constraints through the product structure and relationships between EC objects. This paper also describes a prototype product data management system based on the proposed model In order to demonstrate its effectiveness.

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Spatio-temporal Semantic Features for Human Action Recognition

  • Liu, Jia;Wang, Xiaonian;Li, Tianyu;Yang, Jie
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.10
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    • pp.2632-2649
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    • 2012
  • Most approaches to human action recognition is limited due to the use of simple action datasets under controlled environments or focus on excessively localized features without sufficiently exploring the spatio-temporal information. This paper proposed a framework for recognizing realistic human actions. Specifically, a new action representation is proposed based on computing a rich set of descriptors from keypoint trajectories. To obtain efficient and compact representations for actions, we develop a feature fusion method to combine spatial-temporal local motion descriptors by the movement of the camera which is detected by the distribution of spatio-temporal interest points in the clips. A new topic model called Markov Semantic Model is proposed for semantic feature selection which relies on the different kinds of dependencies between words produced by "syntactic " and "semantic" constraints. The informative features are selected collaboratively based on the different types of dependencies between words produced by short range and long range constraints. Building on the nonlinear SVMs, we validate this proposed hierarchical framework on several realistic action datasets.

Differences in the Control of Anticipation Timing Response by Spatio-temporal Constraints

  • Seok-Hwan LEE;Sangbum PARK
    • Journal of Sport and Applied Science
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    • v.7 no.2
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    • pp.39-51
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    • 2023
  • Purpose: The purpose of this study was to investigate differences in the control process to satisfy spatial and temporal constraints imposed upon the anticipation timing response by analyzing the effect of spatio-temporal accuracy demands on eye movements, response accuracy, and the coupling of eye and hand movements. Research design, data, and methodology: 12 right-handed male subjects participated in the experiment and performed anticipation timing responses toward a stimulus moving at three velocities (0.53m/s, 0.66m/s, 0.88m/s) in two task constraint conditions (temporal constraint, spatial constraint). During the response, response accuracy and eye movement patterns were measured from which timing and radial errors, the latency of saccade, fixation duration of the point of gaze (POG), distance between the POG and stimulus, and spatio-temporal coupling of the POG and hand were calculated. Results: The timing and radial errors increased with increasing stimulus velocity, and the spatio-temporal constraints led to larger timing errors than the temporal constraints. The latency of saccade and the temporal coupling of eye and hand decreased with increasing stimulus velocity and were shorter and longer respectively in the spatio-temporal constraint condition than in the temporal constraint condition. The fixation duration of the POG also decreased with increasing stimulus velocity, but no difference was shown between task constraint conditions. The distance between the POG and stimulus increased with increasing stimulus velocity and was longer in the temporal constraint condition compared to the spatio-temporal constraint condition. The spatial coupling of eye and hand was larger with the velocity 0.88m/s than those in other velocity conditions. Conclusions: These results suggest that differences in eye movement patterns and spatio-temporal couplings of stimulus, eye and hand by task constraints are closely related with the accuracy of anticipation timing responses, and the spatial constraints imposed may decrease the temporal accuracy of response by increasing the complexity of perception-action coupling.

English Teachers' Responses to Doing Action Research

  • Yang, Tae-Sun
    • English Language & Literature Teaching
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    • v.15 no.2
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    • pp.245-259
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    • 2009
  • The purpose of this study was to investigate English teachers' perceptions about doing their own action research to find out the benefits of involvement in action research. I believe that teachers should engage in curriculum research and development because it relates to their own classrooms and because a primary aim for teacher education program is to give teachers ways of exploring their own classrooms. I focused on 17 graduate students who had undertaken action research during the fall semester of 2007 and administered a questionnaire about their perceptions of doing action research. The results revealed that their perceptions of doing action research fell into the following two categories, positive and negative aspects. For positive aspects, they experienced a sense of personal and professional growth and they underwent identity transformation from passive, etic-oriented, and uncritical to active, emic-oriented, and critical teachers. However, many of them expressed that major obstacles to doing action research were time constraints and lack of skills or training in conducting action research. Thus, it is suggested that both pre- and in-service teachers should consider conducting a language teaching diary study, doing collaborative action research, and acquiring all the necessary skills for conducting action research.

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Workflow Interruptions and Failed Action Regulation in Surgery Personnel

  • Elfering, Achim;Nutzi, Marina;Koch, Patricia;Baur, Heiner
    • Safety and Health at Work
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    • v.5 no.1
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    • pp.1-6
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    • 2014
  • Background: Workflow interruptions during surgery may cause a threat to patient's safety. Workflow interruptions were tested to predict failure in action regulation that in turn predicts near-accidents in surgery and related health care. Methods: One-hundred-and-thirty-three theater nurses and physicians from eight Swiss hospitals participated in a cross-sectional questionnaire survey. The study participation rate was 43%. Results: Structural equation modeling confirmed an indirect path from workflow interruptions through cognitive failure in action regulation on near-accidents (p < 0.05). The indirect path was stronger for workflow interruptions by malfunctions and task organizational blockages compared with workflow interruptions that were caused by persons. The indirect path remained meaningful when individual differences in conscientiousness and compliance with safety regulations were controlled. Conclusion: Task interruptions caused by malfunction and organizational constraints are likely to trigger errors in surgery. Work redesign is recommended to reduce workflow interruptions by malfunction and regulatory constraints.

AN ITERATIVE ROW-ACTION METHOD FOR MULTICOMMODITY TRANSPORTATION PROBLEMS

  • Ryang, Yong Joon
    • Korean Journal of Mathematics
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    • v.4 no.1
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    • pp.7-16
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    • 1996
  • The optimization problems with quadratic constraints often appear in various fields such as network flows and computer tomography. In this paper, we propose an algorithm for solving those problems and prove the convergence of the proposed algorithm.

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Analysis of Timing Constraints for Timely Collaboration among Web-Based Distributed Business Systems (웹기반 분산 기업시스템의 적기협력을 위한 시간 제약 조건의 분석)

  • Suh, Tae-Jung;Lee, Dong-Woo
    • 대한공업교육학회지
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    • v.33 no.2
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    • pp.232-247
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    • 2008
  • Timely collaboration among businesses is required these days such as in B2B E-Commerce. That is, emergency requests or urgent information among businesses should be processed in an immediate mode. In this paper we investigate the semantics on timing constraints of timely collaboration among businesses in terms of event, data, and action and present ECA rule construction related to the timing constraints and its violation. The prototype is implemented using web-based active functionality component.

A Study on Stable Grasping Control of Dual-fingers with Soft-Tips (소프트-팁이 장착된 듀얼-핑거의 안정적 파지 제어에 관한 연구)

  • 심재군;한형용;양순용;이병룡;안경관;김성수
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2002.10a
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    • pp.219-224
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    • 2002
  • This paper aims to derive a mathematical model of the dynamics of handling tasks in robot finger which stable grasping and manipulates a rigid object with some dexterity. Firstly, a set of differential equation describing dynamics of the manipulators and object together with geometric constraint of tight area-contacts is formulated by Lagrange's equation. Secondly, problems of controlling both the internal force and the rotation angle of the grasped object under the constraints of area-contacts of tight area-contacts are discussed. The effect of geometric constraints of area-contacts on motion of the overall system is analyzed and a method of computer simulation for overall system of differential-algebraic equations is presented. Thirdly, simulation results are shown and the effects of geometric constraints of area-contact is discussed. Finally, it is shown that even in the simplest case of dual single D.O.F manipulators there exists a sensory feedback from sensing data of the rotational angle of the object to command inputs to joint actuators and this feedback connection from sensing to action eventually realizes secure grasping of the object, provided that the object is of rectangular shape and motion is confined to a horizontal plane.

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A method of optimum design based on reliability for antenna structures

  • Chen, Jianjun;Wang, Fanglin;Sun, Huaian;Zhang, Chijiang
    • Structural Engineering and Mechanics
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    • v.8 no.4
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    • pp.401-410
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    • 1999
  • A method of optimum design based on reliability for antenna structures is presented in this paper. By constructing the equivalent event, the formula is derived for calculating the reliability of reflector accuracy of antenna under the action of random wind load. The optimal model is developed, in which the cross sectional areas of member are treated as design variables, the structure weight as objective function, the reliability of reflector accuracy and the strength or stability of structural elements as constraints. The improved accelerated convergence gradient algorithm developed by the author is used. The design results show that the method in this paper is feasible and effective.

Research of Stable Grapsing in Field Robot (Field-Robot의 안정적 파지운동 제어에 관한 연구)

  • 박경택;심재군;한현용;양순용;이병룡
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.10a
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    • pp.492-495
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    • 1997
  • This paper aims to derive a mathematical model of the dynamics of handling task in field robot which stable grasping and manipulates a rigid object with some dexterity. Firstly, a set of differential equation describing dynamics of the manipulators and object together with geometric constraints of tight area-contacts on motion of the overall system is analyzed and a method of computer simulation for overall system of differential-algebraic equations is presented. Thirdly, simulation results are shown and the effects of geometric constraints of contact-area are discussed. Finally, it is shown that even in the simplest case of dual single D.O.F. manipulators there exists a sensory feedback from sensing data of he rotational angle of the object to command inputs to joint actuators and this feedback connection from sensing to action eventually realizes secure grasping of the object, provided that he object is of rectangular shape and motion is confined to a horizontal

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