SRAM-based FPGAs have been studied for their sensitivity to atmospheric high energy neutrons. FPGAs with the supply voltage 5V and 3.3V were irradiated by 0-11, 14 and 100 MeV neutrons and showed a very low SEU suscep...
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SRAM-based FPGAs have been studied for their sensitivity to atmospheric high energy neutrons. FPGAs with the supply voltage 5V and 3.3V were irradiated by 0-11, 14 and 100 MeV neutrons and showed a very low SEU susceptibility.
This paper presents the design of an active surveillance system consisting of an intelligent-controller and two video cameras (one with a fixed wide field of view and the other with a narrow moveable field of view). T...
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This paper presents the design of an active surveillance system consisting of an intelligent-controller and two video cameras (one with a fixed wide field of view and the other with a narrow moveable field of view). The controller, which is implemented within a single Altera FLEX 10K device, combines the functions of image capture and display, motion detection, background image update and control of the moveable camera. Correct functionality of the controller chip has been verified by simulation.
Integrated Device Technology (IDT) was faced with the problem of installing a new, modern Class 1 cleanroom for the production of 8 inch, 0.35 micron high speed Sram chips using sophisticated controls under tight budg...
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Integrated Device Technology (IDT) was faced with the problem of installing a new, modern Class 1 cleanroom for the production of 8 inch, 0.35 micron high speed Sram chips using sophisticated controls under tight budget constraints. An added requirement was that the new system be suitable for future expansion in the production facility. In addition, the system had to be suitable for operation and maintenance by a small staff. Installation of a commercial control system, though attractive financially, had several technical challenges. The critical nature of the control of the energy center and Fab air envelope preclude the use of a proprietary, closed system that was not industrially hardened and incapable of redundancy. The system selected utilized conventional programmable logic controllers (PLCs) with Ethernet and SNP communications links, integrated with redundant HP Unix 735 workstations and HP X-terminal operator stations. The system was sized and designed for upgrades of the entire production facility. To control the processes, over 300 templates and 700 control screens were created. The system currently has over 3000 real world I/O, a database of over 10,000, and is designed to grow to over 25,000 points. Final install cost was on the order of one-third the cost of a conventional distributed control system (DCS). This paper describes the rationale used to approach the problem, compares alternative solutions, touches on significant details of installation and commissioning, and reports on system performance.
An intrinsic safety PLC has been developed. This PLC has been built to be used in dangerous environments, such inside a mine, where there are risk of explosion. A μP MC68000 has been used as processor and the PLC inc...
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An intrinsic safety PLC has been developed. This PLC has been built to be used in dangerous environments, such inside a mine, where there are risk of explosion. A μP MC68000 has been used as processor and the PLC incorporates a security system based on the use of fiber optics and the μC MC68HC11E2. Moreover, there are conventional digital and analog I/O cards. There are two levels of programming, a textual level and a graphic level. The PLC is programmed from a personal computer through a serial port. It is programmed off line.
The programmablelogic Controller (PLC) SCADA upgrade for the Inuvik Power Station replaced an outdated SCADA system and incorporates automatic features of modern diesel generating stations. The modern PLC based contr...
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The programmablelogic Controller (PLC) SCADA upgrade for the Inuvik Power Station replaced an outdated SCADA system and incorporates automatic features of modern diesel generating stations. The modern PLC based control system provides many advantages: Reliable control system components;industry standard hardware and software;a network infrastructure for future control scenarios;computerized maintenance systems;direct link between plant floor and head office. This paper focuses on the PLC SCADA upgrade at Inuvik explaining the following: Why the project was taken on;technical detail of the project;features of the system.
IEC 1131-3 is a standard for PLCs, defining four programming languages and a type of Grafcet, Sequential Function Charts (SFC). An object-oriented prototype of SFC and the language Function Block Diagram have been imp...
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IEC 1131-3 is a standard for PLCs, defining four programming languages and a type of Grafcet, Sequential Function Charts (SFC). An object-oriented prototype of SFC and the language Function Block Diagram have been implemented. Various execution methods are discussed. Algorithms for local and global sorting are implemented and evaluated. The standard is found to be unclear in some parts.
A quick overview is presented of the application of programmablelogic Controller (PLC) based controls to a major PP&L substation and the method used to move the 9-230 kV lines from the old control system to the n...
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A quick overview is presented of the application of programmablelogic Controller (PLC) based controls to a major PP&L substation and the method used to move the 9-230 kV lines from the old control system to the new system. The project spanned a period of more than four years, and a cost of approximately $5,500,000. The move had to be accomplished in very tight time frame, in a specific sequence, and with severe restrictions on the length of the individual outages.
To ensure that the ultimate goal of a correct translation from source code to executable code, a formal semantics of the safe subset is required. IEC 113-3 provides formal syntax for ST and IL but only defines semanti...
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To ensure that the ultimate goal of a correct translation from source code to executable code, a formal semantics of the safe subset is required. IEC 113-3 provides formal syntax for ST and IL but only defines semantics by example. Work needs to be carried out on the production of validation suites for IEC 1131-3 safe language compilers. Although IEC 1131-3 compilers are smaller than Ada compilers, if the effort of validating compilers is too great, some form of language annotations need to defined to allow correctness demonstrations to be performed. However, even if safe subsets are not available, awareness of ill-defined language features can be used to develop coding standards which can be applied on software projects.
Architects of programmablelogic devices (PLDs) face several challenges when optimizing a new device family for low manufacturing cost. When given an aggressive die-size goal, functional blocks that seem otherwise ins...
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ISBN:
(纸本)9780897919784
Architects of programmablelogic devices (PLDs) face several challenges when optimizing a new device family for low manufacturing cost. When given an aggressive die-size goal, functional blocks that seem otherwise insignificant become targets for area reduction. Once low die cost is achieved, it is seen that testing and packaging costs must be considered. Interactions among these three cost contributors pose trade-offs that prevent independent optimization. This paper discusses solutions discovered by the architects optimizing the Altera FLEX 6000 architecture.
A report on various methods for integrating scale and weight information with programmable logic controllers (PLC) was presented. The need to install improved solutions by manufacturers for statistical process control...
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A report on various methods for integrating scale and weight information with programmable logic controllers (PLC) was presented. The need to install improved solutions by manufacturers for statistical process control for increasing raw materials savings and productivity was addressed. Development of flexible weighing instruments to meet the demands for the cost of production and quality were proposed. The flexibility of setpoint control and batching systems for scale companies was enhanced resulting in a high degree of control during batch mixing.
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