A critical step towards certifying safety-critical systems is to check their conformance to hard realtime requirements. A promising way to achieve this is by building the systems from pre-verified components and verif...
详细信息
The software of programmable logic controllers (PLC) for Safety Instrumented Systems in the oil and gas industry is designed based on safety specifications that must be validated prior to deployment. This paper propos...
详细信息
Connectors and connection technologies are perceived as a major innovation driver in digitalization and networking of future production facilities, as its interface functionality in between machines, programmable logi...
详细信息
Constrained Random Verification (CRV) is becoming the mainstream methodology for the functional verification of complex System on Chip (SoC) designs. In order to achieve verification closure, CRV tools have to produce...
详细信息
The paper discusses the design process of a programmablelogic controller implemented by means of FPGA device. Designed PLC is to be compliant with EN 61131-3 standard. Diiferent aspects of instruction list and hardwa...
详细信息
The paper discusses the design process of a programmablelogic controller implemented by means of FPGA device. Designed PLC is to be compliant with EN 61131-3 standard. Diiferent aspects of instruction list and hardware architecture designing are presented, e.g. PLC structure with particular emphasis on central processing unit or memory map. Conclusions on an EN 61131-3 Standard are also shown. The developed PLC is implemented using FPGA device. This gives opportunity to develop interesting solutions. For example, using dual port RAM gives us opportunity to develop bit/word access without necessity of masking bits. Up to date FPGA devices have also disadvantage - there are no tri-state buffers inside. This is the reason for using multiplexers that control traffic on busses.
Energy efficiency in heating, ventilating, and air-conditioning (HVAC) systems is a primary concern in process projects, since the energy consumption has the highest percentage in HVAC for all processes. Without sacri...
详细信息
Energy efficiency in heating, ventilating, and air-conditioning (HVAC) systems is a primary concern in process projects, since the energy consumption has the highest percentage in HVAC for all processes. Without sacrifice of thermal comfort, to reset the suitable operating parameters, such as the humidity and air temperature, would have energy saving with immediate effect. In this paper, the simulation-optimization approach described the effective energy efficiency for HVAC systems which are used in industrial process. Due to the complex relationship of the HVAC system parameters, it is necessary to suggest optimum settings for different operations in response to the dynamic cooling loads and changing weather conditions during a year. Proportional-integral-derivative (PID) programming was developed which can effectively handle the discrete, nonlinear and highly constrained optimization problems. Energy efficiency process has been made by controlling of alternative current (AC) drivers for ventilation and exhaust fans, according to supplied air flow capacity and differential air pressure between supplied and exhaust air. Supervisory controller software was developed by using programmablecontrollers and human machine interface (HMI) units. The new designed HVAC control system would have a saving potential of about 40% as compared to the existing operational settings, without any extra cost.
The paper presents the Arithmetic and logic Unit (ALU) of a prototype programmablelogic Controller (PLC), implemented in an FPGA device. The PLC implements on the machine language level a subset of the instruction se...
详细信息
The paper presents the Arithmetic and logic Unit (ALU) of a prototype programmablelogic Controller (PLC), implemented in an FPGA device. The PLC implements on the machine language level a subset of the instruction set defined in the EN 61131-3 norm. The design was prepared as a set of synthesizable Verilog, and VHDL models. The ALU can execute 32 operations, which include the basic logic operations, comparators, and the four basic arithmetic operations. The operations can be performed for fixed-point, and floating-point numbers. All the operations are implemented fully in hardware, so the solution is fast. The HDL models used for synthesis can be easily ported to other FPGA architectures, or to an ASIC.
The software of programmable logic controllers (PLC) for Safety Instrumented Systems in the oil and gas industry is designed based on safety specifications that must be validated prior to deployment. This paper propos...
详细信息
The software of programmable logic controllers (PLC) for Safety Instrumented Systems in the oil and gas industry is designed based on safety specifications that must be validated prior to deployment. This paper proposes a method for the automatic test of the Cause and Effect Matrix specifications on PLC systems. For such testing, the specifications are represented as a set of Petri net models that observe the controlled system behavior. The use of a formal model allows to systematically compose and translate the Petri Nets into a program that commands the PLC inputs and observes when the PLC outputs fail the safety specifications. A prototype tool has been developed to automatically perform the test of the Cause and Effect Matrix on a given PLC. A furnace project has been used to ascertain that the proposed method is easy to use and viable.
Several new electronic functions are constantly being integrated into a silicon-on-chip (SoC) encapsulated in a less than 0.5 mm pitch array package, making the future bright for Embedded Board Test (EBT). The SoC wil...
详细信息
Several new electronic functions are constantly being integrated into a silicon-on-chip (SoC) encapsulated in a less than 0.5 mm pitch array package, making the future bright for Embedded Board Test (EBT). The SoC will become a main stream component in all consumer portable devices extending into IoT devices. Embedded Board Test (EBT) uses the IEEE defined in-chip access to verify that the IC is attached to the PCBA and in good working condition. It then extends the tests to surrounding components and potentially drives through to test ICs further away. The EBT testing concept suits HDI PCBA (printed circuit board assembly) designs in which one or more CPU or SoC functions as the brain. Successful adoption of EBT requires it to be crafted early in PCBA design to develop the test software as the PCBA design evolves and matures. Test coverage lost due to buried traces can be recovered using EBT, which makes it a complementary test to ICT. Pairing ICT and EBT is ideal as ICT can perform unpowered tests to locate and pinpoint short and open defects, as well as wrong components. A key ingredient in the success of EBT, similar to ICT and FT, is the test fixture and fixture automation.
Four partners - two SMEs and two research institutes - have united forces to elaborate principles and building blocks to be exploitable for the embedded condition monitoring system with advanced features. Existing nov...
详细信息
Four partners - two SMEs and two research institutes - have united forces to elaborate principles and building blocks to be exploitable for the embedded condition monitoring system with advanced features. Existing novel kind of probabilistic logic was selected for propagation and compounding of information within the hierarchical distributed system, taking pervasive uncertainty of available data into account. Efficient algorithms were developed for teal-time quantification of uncertainty of measured signals. Significant effort is devoted to meaningful transformation of the probabilistic outputs into clear notifications for operators and maintenance personnel. Variety of particular solutions take advantage of the specific expertise of the involved partners and allow consideration of various future applications. Currently, the system is in the stage of testing in a metal-processing plant.
暂无评论