This paper presents a programmable system design methodology used for controlling and supervising the motors of pumping units in petroleum extraction operations. The system is based on using programmablelogic Control...
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ISBN:
(纸本)9786197105124
This paper presents a programmable system design methodology used for controlling and supervising the motors of pumping units in petroleum extraction operations. The system is based on using programmable logic controllers (PLCs), fixed and mobile data networks, TCP/IP protocols and GPRS services.
By comparing various field bus technology, considering automobile electrical control system its own situation, we establish the automobile electrical control system method based on PLC mixed network, discuss the syste...
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ISBN:
(纸本)9783038352259
By comparing various field bus technology, considering automobile electrical control system its own situation, we establish the automobile electrical control system method based on PLC mixed network, discuss the system's design goals, function and main structure;Introduce PLC bus and LIN1.2 bus basic theory and protocol. Design the hardware circuit based on PLC bus and LIN1.2 bus protocol strictly including PLC node circuit design, LIN node circuit design and PLC/LIN gateway circuit design. The chips used in the circuit design and their performances are also detailed introduced. In the end, the system software is designed and the main flow chart is also given in this study.
Industrial control systems (ICS) face daily cyber security threats, can have a significant impact to the security of our nation, and present a difficult challenge to defend. Critical infrastructures, including militar...
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Industrial control systems (ICS) face daily cyber security threats, can have a significant impact to the security of our nation, and present a difficult challenge to defend. Critical infrastructures, including military systems like the machinery control systems (MCS) found onboard modern U. S. warships, are affected because of their use of commercial automation solutions. The increase of automated control systems within the U. S. Navy saves in manpower costs but increases the need for cyber security research and defense. Research is needed to assess and contribute solutions to ICS security problems. This thesis describes the MCS security testbed, which supports research in the security of shipboard machinery control systems. The testbed has been conceptualized, designed and implemented with the vision of supporting research and experimentation on the defense of ICS and MCS systems. The testbed provides the ability to analyze vulnerabilities, test defenses and replicate attacks on authentic physical industrial control equipment. The MCS security testbed is a tool that may help counter cyber security threats facing the defense industrial base today. Future solutions to attacks on control systems in the nation's critical infrastructure begin with experimentation using authentic test environments.
Recent attacks on industrial control systems (ICSs), like the highly publicized Stuxnet malware, have perpetuated a race to the bottom where lower level attacks have a tactical advantage. programmable logic controller...
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Recent attacks on industrial control systems (ICSs), like the highly publicized Stuxnet malware, have perpetuated a race to the bottom where lower level attacks have a tactical advantage. programmable logic controller (PLC) firmware, which provides a software- driven interface between system inputs and physically manifested outputs, is readily open to modification at the user level. Current e orts to protect against firmware attacks are hindered by a lack of prerequisite research regarding details of attack development and implementation. In order to obtain a more complete understanding of the threats posed by PLC firmware counterfeiting and the feasibility of such attacks, this research explores the vulnerability of common controllers to intentional firmware modifications. After presenting a general analysis process that takes advantage of various techniques and methodologies applied to similar scenarios, this work derives the firmware update validation method used for the Allen-Bradley ControlLogix PLC. A proof of concept demonstrates how to alter a legitimate firmware update and successfully upload it to a ControlLogix L61. Possible mitigation strategies discussed include digitally signed and encrypted firmware as well as preemptive and post-mortem analysis methods to provide protection. Results of this e ort facilitate future research in PLC firmware security through direct example of firmware counterfeiting.
This paper focuses on the execution of conformance testing of PLC with I/O scanning which executes a control code; it is assumed that the test sequence has been built from a finite state machine that represents the sp...
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This paper focuses on the execution of conformance testing of PLC with I/O scanning which executes a control code; it is assumed that the test sequence has been built from a finite state machine that represents the specified behavior. It is first shown that the conformance relation which allows to decide whether the implementation conforms to the specification or not must be defined from a sequence of observations, and not from only one observation, to take into account the delays introduced by the I/O scanning. Then, a second conformance relation is proposed to avoid that asynchronous detection of synchronous input changes leads to biased or non-valid verdicts; this new relation is defined from the analysis of concurrent transitions and accepted sequences in the specification model.
This paper describes the implementation of an efficient model predictive control (MPC) approach on a standard programmable logic controller (PLC). PLCs are commonly used in industrial automation but are typically limi...
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This paper describes the implementation of an efficient model predictive control (MPC) approach on a standard programmable logic controller (PLC). PLCs are commonly used in industrial automation but are typically limited in view of computational performance and memory. The MPC scheme in this contribution is well suited for nonlinear input constrained systems with sampling times in the millisecond range and can also be applied to tracking control problems. Experimental results for a laboratory crane demonstrate the real-time applicability of the PLC implementation.
Liquid fuels like furnace oil are predominantly used in industrial application. Viscosity is the most important characteristic in the storage and use of fuel oil. Viscosity influences the degree of pre-heat required f...
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Liquid fuels like furnace oil are predominantly used in industrial application. Viscosity is the most important characteristic in the storage and use of fuel oil. Viscosity influences the degree of pre-heat required for handling, storage and satisfactory atomization. If the oil is too viscous, it may become difficult to pump to light the burner as well as tough to operate which causes poor atomization. Therefore pre-heating is necessary for proper atomization as it may result in the formation of carbon deposits on the burner walls. This work presents the development of a modular temperature control system for furnace feed oil and implemented using a modern high performance PLC.
programmable logic controllers (PLCs) are complex embedded systems that are widely used in industry. This paper presents a component-based modeling and validation method for PLC systems using the behavior-interaction-...
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programmable logic controllers (PLCs) are complex embedded systems that are widely used in industry. This paper presents a component-based modeling and validation method for PLC systems using the behavior-interaction-priority (BIP) framework. We designed a general system architecture and a component library for a type of device control system. The control software and hardware of the environment were all modeled as BIP components. System requirements were formalized as monitors. Simulation was carried out to validate the system model. A realistic example from industry of the gates control system was employed to illustrate our strategies. We found a couple of design errors during the simulation, which helped us to improve the dependability of the original systems. The results of experiment demonstrated the effectiveness of our approach.
With glass fiber manufacturing industry as an example, studied the design and application of automatic logistics system based on 2-Dimensional Bar Code. The system through the analysis of information flow in the proce...
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ISBN:
(纸本)9781479958252
With glass fiber manufacturing industry as an example, studied the design and application of automatic logistics system based on 2-Dimensional Bar Code. The system through the analysis of information flow in the process of production, designed and studied the application in the production process about Fieldbus Control System, programmable logic controller, Manufacturing Execution System, Enterprise Resource Planning, 2-Dimensional Bar Code image system. Automation logistics system for the enterprise success implementation of integrative management provided an effective method for reference, implement the efficient intelligent monitoring and management of manufacturing process.
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