• Title/Summary/Keyword: concurrent tasks

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The Web-Based Engineering Process Framework for Concurrent Engineering (동시공학 구현을 위한 Web 기반의 공학 프로세서 지원 프레임워크)

  • Kim, Hyun;Myong, Jae-Hyong;Mok, Kyung-Tae
    • Korean Journal of Computational Design and Engineering
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    • v.3 no.4
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    • pp.283-292
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    • 1998
  • The engineering process including design, analysis/evaluation and manufacturing activities is becoming one of the key issues to embody a concurrent engineering concept. This paper proposes a framework to integrated the complicated engineering design and manufacturing processes under the concurrent engineering environment. The framework offers the following facilities: (1) to represent the complicated engineering process (2) to coordinate design activities and execute the process in a distributed environment (3) to support a communication among the related engineers. The engineering processes is depicted using process flow graphs that consist in tasks and the corresponding input and output data. The engineering activities in the defined processes can be executed in a distributed environment through process controller of the framework. Engineers can communicate to suggest their opinions and to exchange product information in the framework. We have conformed the CORBA standard to integrate various distributed engineering the and communicate among them, and used a Java to support the platform independent environment on the Internet. Since the proposed framework an be a formal approach to integrate the engineering processes by providing formalism, parallelism, reusability, and flexibility, it can be effectively applied to embody the concurrent engineering concept in a distributed environment.

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Concurrent Validity between Figure-of-8 Walking Test and Functional Tests Included Tasks for Dynamic Balance and Walking in Patient with Stroke (뇌졸중 환자에서 8자 모양 경로 보행 검사의 동시 타당도 연구)

  • Kim, Joong-Hwi;Park, Ji-Won
    • The Journal of Korean Physical Therapy
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    • v.24 no.5
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    • pp.325-333
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    • 2012
  • Purpose: The purpose of this study was to determine the concurrent validity between Figure-of-8 Walking Test (F8W), Berg Balance Scale (BBS), Four Squared Step Test (FSST), and Timed UP and GO Test (TUG) in patients with stroke. Methods: Forty two participants (26 men, 16 women, $55.0{\pm}11.72$) with at least three months post stroke who were able to walk at least 10 m without walking aid participated in this study. Assessment of concurrent validity between the F8W (time and steps) and BBS was performed using Spearman rank order correlation and between the F8W (time and steps), FSST and TUG assessed using Pearson correlation. Results: The time of the F8W showed correlation with BBS (r=-0.46, p<0.01), FSST (r=0.64, p<0.01), and TUG (r=0.81, p<0.01), and steps of the F8W showed correlation with BBS (r=-0.43, p<0.01), FSST (r=0.47, p<0.01), and TUG (r=0.51, p<0.01). Conclusion: The F8W is a valid measure of balance and walking skill among patients with stroke and may provide complementary information with regard to dynamic balance and functional walking for the real life of stroke patients.

A Triangularization Algorithm Solving for the Complex Design with Precedence Constraints and IDEF3 Modeling in Concurrent Engineering (전제조건과 IDEF3를 응용한 동시공학환경에서의 복합설계)

  • Cho, Moon-Soo;Lim, Tae-Jin
    • Journal of Institute of Control, Robotics and Systems
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    • v.15 no.7
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    • pp.742-752
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    • 2009
  • Engineering design involves the specification of many variables that define a product, how it is made, and how it behaves applied to computer, communication and control fields. Before some variables can be determined, other variables must first be known or assumed. This fact implies a precedence order of the variables, and of the tasks of determining these variables consequently. Moreover, design of complex systems may involve a large number of design activities. In this paper, the activity-activity incidence matrix is considered as a representation of design activity analysis which mainly focuses on the precedence constraint with an object of doing IDEF3 in process-centered view. In order to analyze the activity-activity incidence matrix, a heuristic algorithm is proposed, which transforms an activity-activity, parameter-formula, and parameter-parameter incidence matrix into a lower triangular form. The analysis of the structured matrices can not only significantly reduce the overall project complexity by reorganizing few critical tasks in practice, but also aims at obtaining shorter times considering the solution structure by exploring concurrency.

A Study for Process Representation using STEP (STEF을 이용한 프로세스 표현에 관한 연구)

  • 황호진;이수홍
    • Korean Journal of Computational Design and Engineering
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    • v.4 no.4
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    • pp.371-380
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    • 1999
  • This study proposes a process information model which can integrate various activities during the product development process, the system which can manage the process. Development process information will allow designers and managers to access previous tasks readily and utilize the information in making decisions at hand. While developing products in heterogeneous and distributed environments, concurrent and collaborative designs can be achieved by STEP. The process model in this study divides the task of product development into two fundamental parts, Specific Process(SP) and Normal Process(NP). SP includes the specific information and refer to those defined by prior STEP. NP is routine process excluded from being defined as SP. Due data information can be added to manage development pace and to show delayed tasks. As two or more different processes can be linked to show the entire development flow, Static STEP information can be dynamically interlaced. Remote location operations can be incorporated on the Internet using STEP, and information can be shared. The system has been built upon a process model schema so that task stage, design history, and different development style can be managed and accessed for each component. The system has been proven efficient in information management and exchange by several scenario testings.

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A Design and Implementation of Concurrent Synchronizations Protocol of Multiple Client (다수 클라이언트의 동시 동기화 프로토콜 설계 및 구현)

  • Kim, Hong-Ki;Lim, Chang-Woo;Lee, Sang-Sin;Kim, Dong-Hyun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.10a
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    • pp.135-138
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    • 2008
  • The existing protocol which processes sequentially synchronization has the problem where synchronization tasks which are requested subsequently from multiple client. Should be waited for a long time. In this paper, we propose a implementation of concurrent synchronization protocol that is capable of reducing the waiting time. If there are no update conflicts among different synchronization tasks, the proposed protocol synchronizes using the multi-queue based on the round-robin scheme, in order to reduce the waiting time.

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Exploring On-Chip Bus Architectures for Multitask Applications

  • Kim, Sung-Chan;Ha, Soon-Hoi
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.4 no.4
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    • pp.286-292
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    • 2004
  • In this paper we present a static performance estimation technique of on-chip bus architectures. The proposed technique requires the static scheduling of function blocks of a task to analyze bus conflicts caused by simultaneous accesses from processing elements to which function blocks are mapped. To apply it to multitask applications, the concurrent execution of the function blocks of different tasks also should be considered. Since tasks are scheduled independently, considering all cases of concurrency in each processing element is impractical. Therefore we make an average estimate on the effects of other tasks with respect to bus request rate and bus access time. The proposed technique was incorporated with our exploration framework for on-chip bus architectures, Its viability and efficiency are validated by a preliminary example.

Scate: A Scalable Time and Energy Aware Actor Task Allocation Algorithm in Wireless Sensor and Actor Networks

  • Sharifi, Mohsen;Okhovvat, Morteza
    • ETRI Journal
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    • v.34 no.3
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    • pp.330-340
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    • 2012
  • In many applications of wireless sensor actor networks (WSANs) that often run in harsh environments, the reduction of completion times of tasks is highly desired. We present a new time-aware, energy-aware, and starvation-free algorithm called Scate for assigning tasks to actors while satisfying the scalability and distribution requirements of WSANs with semi-automated architecture. The proposed algorithm allows concurrent executions of any mix of small and large tasks and yet prevents probable starvation of tasks. To achieve this, it estimates the completion times of tasks on each available actor and then takes the remaining energies and the current workloads of these actors into account during task assignment to actors. The results of our experiments with a prototyped implementation of Scate show longer network lifetime, shorter makespan of resulting schedules, and more balanced loads on actors compared to when one of the three well-known task-scheduling algorithms, namely, the max-min, min-min, and opportunistic load balancing algorithms, is used.

Analysis of the working characteristics of the skipper and risk factors of marine accident in Korea coastal composite fishing vessels (연안복합어선 선장의 업무 특성과 해양사고 위험요소에 대한 분석)

  • KIM, Min-Son;HWANG, Bo-Kyu;CHANG, Ho-Young
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.55 no.2
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    • pp.152-161
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    • 2019
  • This research carried out a study on the job characteristics of the skipper of the coastal composite fishing vessels in order to find a way to prevent the ship collision caused by the highest human error among the marine casualty of fishing boats. Video observation was used as the research method in which six CCD cameras were installed on the vessel to collect image data and data extracted from the image were analyzed to derive the results of the functional activity of skipper according to the fishing operation process of experimental fishing vessel. The results are as follows. The working process of the experimental fishing vessel consisted of navigation for fishing ground, setting line, waiting for hauling line, hauling line and navigation to homeport. In these processes, the skipper was performing watchkeeping in the wheelhouse in which he carried out a single task, a dual task that performed two tasks simultaneously, and a triple task that performed two or more tasks simultaneously. In addition, one of the risk factors causing the collision was a no watchkeeping in the wheelhouse for navigating for fishing ground, waiting for hauling line, and hauling line at 25.4%, 64.6% and 0.3%, respectively among the marine casualty while drowsiness caused 1.2% of the marine casualty in navigating for fishing ground. Concurrent tasks that simultaneously perform two or more tasks that can overlook any other important duties while carrying out watchkeeping in the wheelhouse include 51.3% of navigation for fishing ground, 81.9% of setting line, 19.0% of waiting for hauling line, 87.9% of hauling, and 88.7% of navigation to homeport. The above concurrent tasks yielded an average of 66.1%. Experimental fishing vessels are required to focus on ship handling operations related to fishery operations, and the skipper is assigned more activities and attention to fishery related tasks. Therefore, it is considered desirable to build a collision prevention system that is appropriate to the characteristics of the skipper's work, escaping from transferring the responsibility of ship collision to the skipper completely.

A Study on Concurrent Engineering Methodology for Automobile Wiring Harness Design System (자동차 전장용 에이전트 기반 시스템 연구)

  • Lee, S.H.;Choi, D.S.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.1 no.3
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    • pp.83-94
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    • 1993
  • Design and production of wiring for automobile systems provide the background for the development of concurrent engineering framwork. Key issues include with different parts of the wiring design process and the development of hierarchical representations that capture the different characteristics(e.g., connectivity, geometry) of the harnesses. The abstraction of design information results in features, while the abstraction of operations leads to the development of agents. These abstracts are essential for efficient transactions among people and computer tools in a domain that involves numerous interacting constraints. We have decomposed the wiring design process into four basic categories of tasks that are each addressed by an "agent" : the Environment Editor(EE), the Free Space Manager(FSM), the Wiring Editor(WE), and the Part Selector(PS). In this paper the strategy for the problem decomposition, the definition of features, and the ways in which features are used by various agents, are discussed. We conclude with a discussion of some of the issues raised by the project and the steps underway to address them.

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A Heuristic Approach Solving for the Complex Design with Precedence Constraints in Concurrent Engineering (복합설계를 위한 동시공학적 접근방법)

  • Cho, Moon-Soo;Kim, Chang-Yeong
    • Journal of Korean Institute of Industrial Engineers
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    • v.24 no.2
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    • pp.185-197
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    • 1998
  • Engineering design involves the specification of many variables that define a product, how it is made, and how it behaves. Before some variables can be determined, other variables must first be known or assumed. This fact implies a precedence order of the variables, and of the tasks of determining these variable consequently. Moreover, design of complex systems may involve a large number of design activities. In this paper, the activity-activity incidence matrix is considered as a representation of design activity analysis which mainly focuses on the precedence constraint. In order to analyze the activity-activity incidence matrix, a heuristic algorithm is proposed, which transforms an activity-activity, parameter-formula, and parameter-parameter incidence matrix into a lower triangular form. The analysis of the structured matrices can not only significantly reduce the overall project complexity by reorganizing few critical tasks in practice, but also aims at obtaining shorter times considering the solution structure by exploring concurrency.

  • PDF