In the paper a synthesis method of logiccontrollers for safety critical systems into field programmablelogic is presented. The specification of the system in the form of symbolic, if-then or if-then-else conditional...
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In the paper a synthesis method of logiccontrollers for safety critical systems into field programmablelogic is presented. The specification of the system in the form of symbolic, if-then or if-then-else conditional decision rules is used for directly mapping to netlist format, or transformed into a HDL format that is accepted by standard FPGA simulators and synthesis tools. In addition, models of logiccontrollers are verified using the well-developed Petri net theory, and then they are translated through automated processes into selected FPGA specification format.
A 64 channel and 25GHz spacing multi/demultiplexer has been successfully fabricated bq monolithically integrating a Mach-Zehnder interferometer and two arrayed-waveguide gratings (AWGs) in a PLC chip. The centre wavel...
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A 64 channel and 25GHz spacing multi/demultiplexer has been successfully fabricated bq monolithically integrating a Mach-Zehnder interferometer and two arrayed-waveguide gratings (AWGs) in a PLC chip. The centre wavelength of the AWG was precisely tuned with UV laser irradiation at 193nm.
Resistance to multiple, unrelated cancer chemotherapeutic drugs can be mediated by P-glycoprotein, the MDR1 gene product. Numerous substances, including chemotherapeutic drugs, heavy metals, growth factors, activated ...
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Resistance to multiple, unrelated cancer chemotherapeutic drugs can be mediated by P-glycoprotein, the MDR1 gene product. Numerous substances, including chemotherapeutic drugs, heavy metals, growth factors, activated oncogenes, or changes in temperature increase MDR1 gene expression. Because several of these factors regulate cellular function through the activation of phospholipase C (PLC), we postulated that PLC-mediated signaling could be central to regulating the expression of MDR1. Transfection of NIH 3T3 cells with a pMJ30-PLC-gamma1 expression vector increased the activity of the MDR1 promoter by 2- to 10-fold. PLC-mediated activation required a region between -106 and -99 of the MDR1 promoter. Treatment of cotransfected cells with platelet-derived growth factor further enhanced the activity of the MDR1 promoter. The stimulatory effect of PLC on the MDR1 promoter was increased by cotransfection with constitutively active v-raf and was blocked by the dominant-negative mutant, c-Raf-C4. The activity of mitogen-activated protein kinase (MAPK) was also increased in PLC-gamma1-transfected cells. Furthermore, PD-98059 and U0126, two MAPK inhibitors, blocked PLC-gamma1-induced expression of MDR1. The results of Northern blot analysis showed that activation of PLC by heat shock and growth factors increased expression of endogenous MDR1 mRNA in human renal carcinoma cells. These effects were blocked by inhibitors of the PLC-MAPK pathway. In summary, our results indicate for the first time that activation of PLC by a variety of cellular stimuli can regulate the expression of MDR1 and that the transcriptional modulation of MDR1 expression by PLC is mediated by the Raf-MAPK pathway.
The introduction of the PC in 1981 ushered in a new era of DOS-based programmablelogic controller (PLC) programming software. Later, DOS evolved into Windows and graphical programming techniques became available. At ...
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The introduction of the PC in 1981 ushered in a new era of DOS-based programmablelogic controller (PLC) programming software. Later, DOS evolved into Windows and graphical programming techniques became available. At present, vendors are migrating toward unified programming environments for PLCs and intelligent field devices.
A laboratory batch process is presented as an example for case studies in the verification of hybrid systems. In the process, sodium-chloride solution is first mixed with water and then reduced to the original sodium-...
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A laboratory batch process is presented as an example for case studies in the verification of hybrid systems. In the process, sodium-chloride solution is first mixed with water and then reduced to the original sodium-chloride concentration by evaporation. The paper describes the plant layout, the main process specifications, and the implementation of a particular control scheme. The problem formulation is divided into three parts. First, an abstraction level is considered on which an appropriate production schedule shall be found. Second, the control code as it is really implemented on the programmablelogic Controller (PLC) is gh,en such that its correctness can be analyzed. Finally, a particular sub-problem is derived from the original formulation which makes it necessary to consider the continuous plant dynamics in more detail. Simulation results are provided to illustrate the specific difficulties of the case example.
In this paper, the design of the networks system through CAN bus is presented. To distribute the control points with a long distance and different located for the application to on - off electrical equipment by the re...
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ISBN:
(纸本)0780367154
In this paper, the design of the networks system through CAN bus is presented. To distribute the control points with a long distance and different located for the application to on - off electrical equipment by the remote I/O module. The controlling and communication between the PLC and the remote I/O modules are used by the CAN bus serial communication. In this paper, the experiment has been set up the maximum of 32 remote I/O modules. Each remote I/Os are linked to host PLC programmed for handling a interrupt request from any remote I/O independently. Therefore, the scanning time of the controller not effects. By using this technique, the controller(PLC) can be efficiently applied to the several hundred meters.
This paper presents an application of object-oriented methodology to the development of programmablelogic Controller (PLC) programs. PLC is widely used as computer controller of manufacturing machinery, principally b...
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ISBN:
(纸本)0780367367
This paper presents an application of object-oriented methodology to the development of programmablelogic Controller (PLC) programs. PLC is widely used as computer controller of manufacturing machinery, principally because its robustness and programming simplicity. During the last years, IEC 61131-3 norm has been introduced aiming to provide standard languages and structure to the development environments of PLC programmes, that are instead strictly bound up to now to proprietary languages. Following IEC 61131-3 prescription, is it also possible to develop well structured, object-oriented control software, which was hardly possible with the former vendor-specific low-level languages. This paper describes an application of the novel standard EEC 61131-3 to the development of the control software of a medium complexity manufacturing machinery. Software development methodology is reported and comparison regarding development time, software re-usability and application structuring, is then discussed.
LSI logic licensed the programmablelogic Core (PLC) architecture to allow designers to move some portions of the design later in the cycle. The basic operation of the architecture has been verified using a simple tes...
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ISBN:
(纸本)0780365917
LSI logic licensed the programmablelogic Core (PLC) architecture to allow designers to move some portions of the design later in the cycle. The basic operation of the architecture has been verified using a simple test-chip TestChipA containing only the PLC.
As SoC design enters into mainstream usage, the ability to make post-fabrication changes will become more and more attractive. This ability can be realized using programmablelogic cores. These cores are like any othe...
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ISBN:
(纸本)0780365917
As SoC design enters into mainstream usage, the ability to make post-fabrication changes will become more and more attractive. This ability can be realized using programmablelogic cores. These cores are like any other IP in the SoC design methodology, except that their function can be changed after fabrication. This paper outlines ways in which programmablelogic cores can simplify SoC design, and describes some of the challenges that must be overcome if the use of programmablelogic cores is to become a mainstream design technique.
PLC's and microprocessor relays located in control buildings inside the HV substations were subject to electrical interference substation yard during high voltage air disconnect switching. The interference was due...
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ISBN:
(纸本)0780365690
PLC's and microprocessor relays located in control buildings inside the HV substations were subject to electrical interference substation yard during high voltage air disconnect switching. The interference was due to modifications to a circuit breaker that produced common mode voltages on control circuit wiring in the substation control building and led to equipment damage and misoperation. This paper describes the unusual coupling mechanism that created transient voltages, a comparison to between predicted and measured transients, and a description of use of shielded cable to minimize interference coupling.
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