• Title/Summary/Keyword: Engineering Controls

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신뢰성 있는 통신링크 제공을 위한 DECT 시스템의 데이타 링크제어 프로토콜의 구현 (Implementation of Data Link Control Protocols for Providing Reliable Communication Links in the DECT Mobile System)

  • 최재원;권치성
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 1999년도 추계종합학술대회
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    • pp.356-362
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    • 1999
  • DECT(Digital Enhanced Cordless Telecommunications)는 사설교환기에 이동서비스를 제공하기 위한 통신 규약으로 셀 반경이 100~200 m 정도인 협역상의 이동서비스를 제공하는 초소형 셀룰라(pico-cellular) 방식이고, PSTN을 이용한 저가형 통신서비스를 제공함으로써 빌딩의 옥내형 이동통신을 위한 CSM의 이상적인 보완책으로 각광을 받고 있다. 본 논문에서는 링크제어, 오류제어, 시퀸스제어, 흐름제어 기능의 수행으로 상위 네트워크 계층에게 신뢰성 있는 통신 링크를 제공하는 DECT 시스템의 데이타 링크제어 계층의 구현방법과 기술에 관해 연구하였다.

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가솔린 전자제어 엔진의 기술동향 (Technology Trend of Gasoline Electronic Control Engine)

  • 장경욱
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 제2회 학술대회 논문집 일렉트렛트 및 응용기술전문연구회
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    • pp.1-8
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    • 2000
  • Automotive electronics as we know it today encompasses a wide variety of devices and systems. Key to them all, and those yet to come. is the ability to sense and measure accurately automotive control parameters. In other words, sensors and actuators are the heart of any automotive electronics application. The important of sensors and actuators cannot be overemphasized. The future growth of automotive electronics is arguably more dependent on sufficiently accurate and low-cost sensors and actuators than on computers, controls, displays, and other technologies. Without them, all of controls system - engine. transmission. cruise, braking, traction, suspension, steering, lighting, windshield wipers, air conditioner/hearter - would not be possible. Those controls, of course, are key to car operation and they have made cars over the years more drivable, safe, and reliable. In this lecture, the principle and future trends of electronic control gasoline engine will be discuss.

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Control Effectiveness Analysis of the hawkmoth Manduca sexta: a Multibody Dynamics Approach

  • Kim, Joong-Kwan;Han, Jae-Hung
    • International Journal of Aeronautical and Space Sciences
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    • 제14권2호
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    • pp.152-161
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    • 2013
  • This paper presents a control effectiveness analysis of the hawkmoth Manduca sexta. A multibody dynamic model of the insect that considers the time-varying inertia of two flapping wings is established, based on measurement data from the real hawkmoth. A six-degree-of-freedom (6-DOF) multibody flight dynamics simulation environment is used to analyze the effectiveness of the control variables defined in a wing kinematics function. The aerodynamics from complex wing flapping motions is estimated by a blade element approach, including translational and rotational force coefficients derived from relevant experimental studies. Control characteristics of flight dynamics with respect to the changes of three angular degrees of freedom (stroke positional, feathering, and deviation angle) of the wing kinematics are investigated. Results show that the symmetric (asymmetric) wing kinematics change of each wing only affects the longitudinal (lateral) flight forces and moments, which implies that the longitudinal and lateral flight controls are decoupled. However, there are coupling effects within each plane of motion. In the longitudinal plane, pitch and forward/backward motion controls are coupled; in the lateral plane, roll and side-translation motion controls are coupled.

VHDL을 이용한 확장 인터럽트 제어기의 설계 (Design of the Expanded Interrupt Controller using VHDL)

  • 박성수;박승엽
    • 한국정보통신학회논문지
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    • 제7권3호
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    • pp.558-567
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    • 2003
  • 고성능 모터제어에 이용되는 대부분의 디지털 시그널 프로세서(DSP)에는 외부 인터럽트 입력 채널이 4개 정도 제공되고 있다. 그러나, 모터제어에서 이용될 수 있는 외부 인터럽트의 수는 이보다 훨씬 많은 수이다. 8259와 같은 상용화된 프로그램 가능한 인터럽트 제어기는 8채널의 입력을 기본으로 하고 있으며 보다 많은 인터럽트 입력을 이용하고자 할 경우 이를 종속 연결하여 채널을 확장시켜야 한다. 그리고 모터제어용 마이크로프로세서와의 인터페이스에 있어서 불편한 점이 있으므로 본 논문에서는 상용화된 인터럽트 제어기가 아닌 모터제어용 마이크로프로세서와의 인터페이스에 더욱 적합한 인터럽트 제어기의 구현과 기타의 주변장치들이 구현된 프로그램 가능한 디바이스의 소자 이용률을 높히기 위하여 모터제어에 필요한 수만큼 인터럽트 입력채널을 14채널로 확장한 인터럽트 제어기를 VHDL을 이용하여 설계하였다. 이를 위하여 간단한 인터럽트 제어기의 모델을 제안하였으며, 시뮬레이션을 통해 설계된 제어기의 유용성을 확인하였다.

레이저 변위센서를 이용한 용접선 자동추적에 관한 연구 (A Stuy on Automatic Seam Tracking of Arc Welding Using an Laser Displacement Sensor)

  • 양상민;조택동;서송호
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 춘계학술대회 논문집
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    • pp.680-684
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    • 1996
  • Welding systems cannot adapt to changes in the joint geometry which may occur due to a variety of reason. Automatic seam tracking technigue is essential to adjust the welding torch position in real time as it moves along the seam. Automatic tracking system must keep the welding speed constant unrelation to the change of the welding path. Therefore, the information from the laser displacement sensor must be converted into the input to operate the X-Y table and to rotate the desired torch position by proposed algorithm. In this research, laser displacement sensor is used as a seam finder in the automatic tracking system. X-Y moving table manipulated by ac servo motor controls the position and velocity of the torch-and-sensor part. DC motor controls the position and velocity of the torch. X-Y table controls the position of sensor and relative position of torch is controlled by dc motor which is mounted at sensor-and-torch part. Sensor is always ahead of torch to preview the weld line. From the experimental results, we could see the possiblity that the laser displacement sensor can be used as a seam finder in welding process and that the seam tracking system controlled by proposed algorithm is well done.

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A comparison of individual and combined $_L$-phenylalanine ammonia lyase and cationic peroxidase transgenes for engineering resistance in tobacco to necrotrophic pathogens

  • Way, Heather M.;Birch, Robert G.;Manners, John M.
    • Plant Biotechnology Reports
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    • 제5권4호
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    • pp.301-308
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    • 2011
  • This study tested the relative and combined efficacy of ShPx2 and ShPAL transgenes by comparing Nicotiana tabacum hybrids with enhanced levels of $_L$-phenylalanine ammonia lyase (PAL) activity and cationic peroxidase (Prx) activity with transgenic parental lines that overexpress either transgene. The PAL/Prx hybrids expressed both transgenes driven by the 35S CaMV promoter, and leaf PAL and Prx enzyme activities were similar to those of the relevant transgenic parent and seven- to tenfold higher than nontransgenic controls. Lignin levels in the PAL/Prx hybrids were higher than the PAL parent and nontransgenic controls, but not significantly higher than the Prx parent. All transgenic plants showed increased resistance to the necrotrophs Phytophthora parasitica pv. nicotianae and Cercospora nicotianae compared to nontransgenic controls, with a preponderance of smaller lesion categories produced in Prx-expressing lines. However, the PAL/Prx hybrids showed no significant increase in resistance to either pathogen relative to the Prx parental line. These data indicate that, in tobacco, the PAL and Prx transgenes do not act additively in disease resistance. Stacking with Prx did not prevent a visible growth inhibition from PAL overexpression. Practical use of ShPAL will likely require more sophisticated developmental control, and we conclude that ShPx2 is a preferred candidate for development as a resistance transgene.

Cradle to Gate Emissions Modeling for Scheduling of Construction Projects

  • Sharma, Achintyamugdha;Deka, Priyanka;Jois, Goutam;Jois, Umesh;Tang, Pei
    • 국제학술발표논문집
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    • The 9th International Conference on Construction Engineering and Project Management
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    • pp.975-983
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    • 2022
  • This paper presents an innovative way of integrating scheduling and project controls with the environmental impact of a construction project to track, monitor, and manage environmental emissions at the activity level. As a starting point, scheduling and project controls help monitor the status of a project to provide an assessment of the duration and sequence of activities. Additionally, project schedules can also reflect resource allocation and costs associated with various phases of a construction project. Owners, contractors and construction managers closely monitor tasks or activities on the critical path(s) and/or longest path(s) calculated through network based scheduling techniques. However, existing industry practices do not take into account environmental impact associated with each activity during the life cycle of a project. Although the environmental impact of a project may be tracked in various ways, that tracking is not tied to the project schedule and, as such, generally is not updated when schedules are revised. In this research, a Cradle to Gate approach is used to estimate environmental emissions associated with each activity of a sample project schedule. The research group has also investigated the potential determination of scenarios of lowest environmental emissions, just as project managers currently determine scenarios with lowest cost or time. This methodology can be scaled up for future work to develop a library of unit emissions associated with commonly used construction materials and equipment. This will be helpful for project owners, contractors, and construction managers to monitor, manage, and reduce the carbon footprint associated with various projects.

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서라운드 오디오 시스템을 위한 가상음원의 거리를 조절할 수 있는 인공잔향기 (Artificial reverberation algorithm to control distance of phantom sound source for surround audio system)

  • 심환;서정훈;성굉모
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2005년도 추계종합학술대회
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    • pp.447-450
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    • 2005
  • Multi-channel artificial reverberation algorithm to control perceived direction and distance is described in this paper. In conventional algorithms using IIR filters, reverberation time is the only parameter to be controlled. Moreover, since the convolution-based conventional algorithms apply only same impulse responses, but not considering sound localization, it was not realistic enough. The new algorithm proposed in this paper utilizes early reflections segmented according to the azimuth from which direct sound comes and controls perceived direction by panning the direct sound, and controls perceived distance by adjusting Energy Decay Curve (EDC) of reverberation and gain of the direct sound. In addition, the algorithm enhances Listener Envelopment(LEV) to make late reverberation incoherent among channels.

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상지, 하지에서 발생하는 근골격계질환의 예방 (Prevention of the Musculoskeletal Disorders at Upper or Lower Extremities)

  • 박희석;이윤근;임상혁
    • 대한인간공학회지
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    • 제29권4호
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    • pp.455-463
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    • 2010
  • Work-related musculoskeletal disorders (WMSDs) are recognized as leading causes of significant human suffering, loss of productivity, and economic burdens on our society. WMSDs are associated with work patterns that include fixed or constrained body positions, continual repetition of movements, force concentrated on small parts of the body, cold environment and vibration. Main effort to protect workers from WMSDs should focus on avoiding repetitive patterns of work through engineering controls which may include mechanization, ergonomic design of tools and equipment, and workplace layout. Where elimination of the risk factors is not practical, administrative controls involving job rotation, job enlargement and enrichment, teamwork should be considered.