• Title/Summary/Keyword: shared control

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Mutual exclusion of shared memory access in the simulation software of the midclass commuter (중형항공기 시뮬레이션 소프트웨어의 작업간 공유메모리 사용의 상호배제)

  • 이인석;이해창;이상혁
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.207-209
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    • 1996
  • The software of the midclass commuter flight simulation is running on multiprocessor/multitasking environments The software is consist of tasks which are periodically alive at a given interval. Each task communicates via shared memory. The data shared by tasks is divided by several block. Only one task, called producer, can produce data for a data block but several tasks, called consumers, can read data from the data block. Double buffer and conditional flag are used to implement a mutual exclusion which prevents the producer and consumers from accessing the same data block simultaneously.

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Bounding Worst-Case Performance for Multi-Core Processors with Shared L2 Instruction Caches

  • Yan, Jun;Zhang, Wei
    • Journal of Computing Science and Engineering
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    • v.5 no.1
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    • pp.1-18
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    • 2011
  • As the first step toward real-time multi-core computing, this paper presents a novel approach to bounding the worst-case performance for threads running on multi-core processors with shared L2 instruction caches. The idea of our approach is to compute the worst-case instruction access interferences between different threads based on the program control flow information of each thread, which can be statically analyzed. Our experiments indicate that the proposed approach can reasonably estimate the worst-case shared L2 instruction cache misses by considering the inter-thread instruction conflicts. Also, the worst-case execution time (WCET) of applications running on multi-core processors estimated by our approach is much better than the estimation by simply assuming all L2 instruction accesses are misses.

A Study on Characteristics of Emerging Leadership Researches and the Team Effectiveness of Shared Leadership (현대적 리더십 연구의 특징과 공유리더십의 팀 효과성에 관한 연구)

  • Kim, Jong-Kwan
    • Journal of Digital Convergence
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    • v.15 no.6
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    • pp.207-217
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    • 2017
  • This study first presents the characteristics of emerging leadership researches by theoretically analyzing the studies related to leadership since the Millenium. The first finding is that most of leadership researches shared same if not similar aspects of transformational leadership. Secondly, much of leadership researches centered around horizonally expanded shared/distributed leadership. Thus, this researches analyzed the effectiveness of the shared/distributed leadership theory based on previous researches and found shared/distributed leadership has positive impact on member's recognized performance and innovative behavior. However, in competition-oriented culture, shared/distributed leadership did not control recognized performance of its members. This implies the demand for shared/distributed leadership is necessary today and research on the matter will expanded globally but, the results may differ according to the cultural value of the company.

MAX-MIN Flow Control Supporting Dynamic Bandwidth Request of Sessions (세션의 동적 대역폭 요구를 지원하는 최대-최소 흐름제어)

  • Cho, Hyug-Rae;Chong, Song;Jang, Ju-Wook
    • Journal of Institute of Control, Robotics and Systems
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    • v.6 no.8
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    • pp.638-651
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    • 2000
  • When the bandwidth resources in a packet-switched network are shared among sessions by MAX-MIN flow control each session is required to transmit its data into the network subject to the MAX-MIN fair rate which is solely determined by network loadings. This passive behavior of sessions if fact can cause seri-ous QoS(Quality of Service) degradation particularly for real-time multimedia sessions such as video since the rate allocated by the network can mismatch with what is demanded by each session for its QoS. In order to alleviate this problem we extend the concept of MAX-MIN fair bandwidth allocations as follows: Individual bandwidth demands are guaranteed if the network can accommodate them and only the residual network band-width is shared in the MAX-MIN fair sense. On the other hand if sum of the individual bandwidth demands exceeds the network capacity the shortage of the bandwidth is shared by all the sessions by reducing each bandwidth guarantee by the MAX-MIN fair division of the shortage. we present a novel flow control algorithm to achieve this extended MAX-MIN fairness and show that this algorithm can be implemented by the existing ATM ABR service protocol with minor changes. We not only analyze the steady state asymptotic stability and convergence rate of the algorithm by appealing to control theories but also verify its practical performance through simulations in a variety of network scenarios.

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An Efficient Shared Loaming Scheme for Layered Video Streaming over Application Layer Multicast (응용 계층 멀티캐스트에서 계층형 비디오 스트리밍의 안정성 향상을 위한 효율적인 공유 학습 기법)

  • Park, Jong-Min;Lee, Seung-Ik;Ko, Yang-Woo;Lee, Dong-Man
    • Journal of KIISE:Computing Practices and Letters
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    • v.14 no.2
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    • pp.181-185
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    • 2008
  • Layered video multicast such as RLM Receiver-driven layered multicast) is a premising technique for delivering streaming video to a set of heterogeneous receivers over ALM(Application Layer Multicast) as well as over IP multicast. However, this approach may suffer from unnecessary fluctuation of video quality due to overlapped and failed join-experiments. Though a shared teaming scheme was introduced to resolve these problems, it may cause high control overhead and slow convergence problem when used with ALM. In this paper, we propose a new shared learning scheme for ALM-based layered video multicast which reduces control overhead and convergence latency while keeping the number of fluctuation reasonably small. The simulation results show that the proposed scheme performs better than an ALM-based layered video multicast with shared learning in terms of control overhead and convergence latency.

An Interactive Robotic Cane for Blind Travelers

  • Shim, Inbo;Yoon, Joongsun
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.119.6-119
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    • 2002
  • $\textbullet$ Introduction $\textbullet$ A Robotic Cane "RoJi" $\textbullet$ Shared Navigation Control $\textbullet$ Autonomous Control Mode $\textbullet$ User Control Mode $\textbullet$ Navigation $\textbullet$ Summary

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Design of Real Time Task Scheduling for Line Controller of Continuous Manufacturing Process Automation (연속 공정 자동화를 위한 라인 제어기에서의 실시간 작업 스케쥴링에 관한 연구)

  • Lee, Joon-Soo;Cho, Young-Jo;Lim, Mee-Seub;Park, Jung-Min;Choy, Ick;Lim, Jun-Hong;Kim, Kwang-Bae
    • Proceedings of the KIEE Conference
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    • 1992.07a
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    • pp.365-368
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    • 1992
  • This paper presents an approach to the design of real time task scheduling for a line controller of continuous manufacturing process automation. The line controller has multiprocessor-based architecture with shared memory and is operated by firmware. This firmware contains menu-driven software supporting real-time database management and fuction-block control language. The multitasking line control processor performs the following three functions: 1) interprets the function block control language by virtue of shared memory in the database; 2) invokes an interupt service routine as required by external hardware; 3) detects errors and notifies the user. We propose real time task scheduling method.

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Analysis of differences in human leukocyte antigen between the two Wellcome Trust Case Control Consortium control datasets

  • Jang, Chloe Soohyun;Choi, Wanson;Cook, Seungho;Han, Buhm
    • Genomics & Informatics
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    • v.17 no.3
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    • pp.29.1-29.8
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    • 2019
  • The Wellcome Trust Case Control Consortium (WTCCC) study was a large genome-wide association study that aimed to identify common variants associated with seven diseases. That study combined two control datasets (58C and UK Blood Services) as shared controls. Prior to using the combined controls, the WTCCC performed analyses to show that the genomic content of the control datasets was not significantly different. Recently, the analysis of human leukocyte antigen (HLA) genes has become prevalent due to the development of HLA imputation technology. In this project, we extended the between-control homogeneity analysis of the WTCCC to HLA. We imputed HLA information in the WTCCC control dataset and showed that the HLA content was not significantly different between the two control datasets, suggesting that the combined controls can be used as controls for HLA fine-mapping analysis based on HLA imputation.

Call Admission Control for Shared Buffer Memory Switch Network with Self-Similar Traffic (Self-Similar 트래픽을 갖는 공유버퍼 메모리 스위치 네트워크 환경에서 호 수락 제어 방법)

  • Kim Ki wan;Kim Doo yong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.4B
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    • pp.162-169
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    • 2005
  • Network traffic measurements show that the data traffic on packet switched networks has the self-similar features which is different from the traditional traffic models such as Poisson distribution or Markovian process model. Most of the call admission control researches have been done on the performance analysis of a single network switch. It is necessary to consider the performance analysis of the proposed admission control scheme under interconnected switch environment because the data traffic transmits through switches in networks. From the simulation results, it is shown that the call admission control scheme may not operate properly on the interconnected switch even though the scheme works well on a single switch. In this parer, we analyze the cell loss probability, utilization and self-similarity of output ports of the interconnected networks switch by using shared buffer memory management schemes and propose the new call admission control scheme considering the interconnected network switches under self-similar traffic environments.

Design of a shared buffer memory switch with a linked-list architecture for ATM applications (Linked-list 구조를 갖는 ATM용 공통 버퍼형 메모리 스위치 설계)

  • 이명희;조경록
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.11
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    • pp.2850-2861
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    • 1996
  • This paper describes the design of AATM switch LIS of shared buffer type with linked-list architecture to control memory access. The proposed switch LSI consists of the buffer memory, controller and FIFO memory blocks and two special circuits to avoid the cell blocking. One of the special circuit is a new address control scheme with linked-list architecture which maintains the address of buffer memory serially ordered from write address to read address. All of the address is linked as chain is operated like a FIFO. The other is slip-flag register it will be hold the address chain when readaddress missed the reading of data. The circuits control the buffer memory efficiently and reduce the cell loss rate. As a result the designed chip operates at 33ns and occupied on 2.7*2.8mm$^{2}$ using 0.8.mu.m CMOS technology.

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