7,601 research outputs found

    Engine Speed Control using Online ANN for Vehicle with EMDAP-CVT

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    Controlling engine speed corresponding to load variations and road condition has always been a challenge to automotive engineers. However, with the introduction of Electro-Mechanical Dual Acting Pulley Continuously Variable Transmission (EMDAP-CVT),maintaining constant engine speed based on either its optimum control line or maximum engine power characteristic could be made possible. This paper describes the simulation work in this area carried out by the Drivetrain Research Group at the Automotive Development Centre, Universiti Teknologi Malaysia, Skudai Johor. The developed drive train model is highly non-linear; it could not be controlled satisfactorily by common linear control strategy such as PID controller. To overcome the problem, the use of Artificial Neural Network (ANN) is employed to indirectly control the engine speed by adjusting pulley CVT ratio. Computer simulations showed that applying artificial neural network (ANN) into drive train model could select a proper transmission ratio where the engine could be maintained to run at certain desired engine speed

    KSR v. Teleflex: How “Obviousness” Has Changed

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    In KSR v. Teleflex, the Supreme Court examined the Federal Circuit\u27s obviousness jurisprudence for patents. Both prior to and in this case, the Federal Circuit rigidly applied its judicially created teaching, suggestion, or motivation (TSM) test to determine whether the prior art would direct an inventor of ordinary skill in the art to combine references or elements in references in the same way as the patentee did. The Supreme Court, however, reversed the decision of the Federal Circuit, and held that by applying the TSM test in such a strict manner, the Federal Circuit had analyzed the issue in a narrow, rigid manner inconsistent with [35 U.S.C.] § 103 and our precedents. KSR is now the controlling case defining the proper obviousness analysis for patents

    High-speed civil transport flight- and propulsion-control technological issues

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    Technology advances required in the flight and propulsion control system disciplines to develop a high speed civil transport (HSCT) are identified. The mission and requirements of the transport and major flight and propulsion control technology issues are discussed. Each issue is ranked and, for each issue, a plan for technology readiness is given. Certain features are unique and dominate control system design. These features include the high temperature environment, large flexible aircraft, control-configured empennage, minimizing control margins, and high availability and excellent maintainability. The failure to resolve most high-priority issues can prevent the transport from achieving its goals. The flow-time for hardware may require stimulus, since market forces may be insufficient to ensure timely production. Flight and propulsion control technology will contribute to takeoff gross weight reduction. Similar technology advances are necessary also to ensure flight safety for the transport. The certification basis of the HSCT must be negotiated between airplane manufacturers and government regulators. Efficient, quality design of the transport will require an integrated set of design tools that support the entire engineering design team

    Soil reinforcement with synthetic and natural fibres: a review

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    Problematic soil is a common issue in construction activities, particularly when dealing with peat and clay soils of poor geotechnical properties. Such soils are non-homogeneous, and their properties vary greatly from place to place or, in some cases, even at one place. The growing development demand and insufficient suitable ground have forced the development to use problematic soil. It is therefore important that the soil properties are improved so that any construction thereon is stable and safe. Soil improvement methods are of several different kinds and ways, but the reinforcement of fibre-based approaches have recently gained increasing interest in the field of geotechnical engineering. This technique is currently used in six main areas worldwide, including pavement, road and railway embankment, foundation, slope, and bridge. The main focus of this paper is to examine the feasibility, potential and efficacy of different types of natural and/or synthetic fibres in soil reinforcement by critically reviewing past researches. The pros and cons of natural versus synthetic fibres will also be discussed

    Linear active disturbance rejection control of waste heat recovery systems with organic Rankine cycles

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    In this paper, a linear active disturbance rejection controller is proposed for a waste heat recovery system using an organic Rankine cycle process, whose model is obtained by applying the system identification technique. The disturbances imposed on the waste heat recovery system are estimated through an extended linear state observer and then compensated by a linear feedback control strategy. The proposed control strategy is applied to a 100 kW waste heat recovery system to handle the power demand variations of grid and process disturbances. The effectiveness of this controller is verified via a simulation study, and the results demonstrate that the proposed strategy can provide satisfactory tracking performance and disturbance rejection

    Evaluation of facilities performance on students’ satisfaction in Northern Nigerian Universities

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    Performance evaluation of academic facilities of HEIs is very critical to educational effectiveness. Presently, there is limited or no research/data in Nigeria to assess how extensively the use of or lack of academic facilities benchmarking practices. The aim of this research was to develop a facilities performance framework for HEIs academic facilities in order to serve as a reference model for policy makers while designing HEIs facilities standard targeted towards improving facilities performance for enhanced student satisfaction. Quantitative research approach using survey design was adopted. Data was collected using closed-ended questionnaires distributed to a sample of 1000 student randomly selected from three universities in the northern Nigeria out of which 735 were considered valid for the analysis. Research questions were answered by testing the proposed research hypothesis which were developed for the research. The descriptive analyses were conducted using the Statistical Package for Social Science Software (SPSS version 23) while the inferential statistics were analyzed using a Partial Least Squares Structural Equation Modelling software (SmartPLS version 3.0). Overall, the result found that facilities performance significantly influenced student satisfaction. The R-square value indicated that performance of the HEIs component facilities explained 63 percent of the variance in students’ satisfaction. Furthermore, it was found that 66.7 percent of the performance of HEIs components facilities was explained by the performance of both physical and non-physical facilities that constitutes the HEIs academic facilities. The implication of this results points to the importance of including students’ feedback in the facilities management aspect of HEIs. This is for the fact that students’satisfaction was shown to be significantly related to the condition of the university facilities. It is recommended that future research should focus on identifying students satisfaction with academic facilities in the HEIs using experience as a measure of facilities performance to promote the concept of best practices benchmarking for the institutions to esterblished quality facilities in their institutions

    Functional integration of vertical flight path and speed control using energy principles

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    A generalized automatic flight control system was developed which integrates all longitudinal flight path and speed control functions previously provided by a pitch autopilot and autothrottle. In this design, a net thrust command is computed based on total energy demand arising from both flight path and speed targets. The elevator command is computed based on the energy distribution error between flight path and speed. The engine control is configured to produce the commanded net thrust. The design incorporates control strategies and hierarchy to deal systematically and effectively with all aircraft operational requirements, control nonlinearities, and performance limits. Consistent decoupled maneuver control is achieved for all modes and flight conditions without outer loop gain schedules, control law submodes, or control function duplication

    Knowledge-based reasoning in the Paladin tactical decision generation system

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    A real-time tactical decision generation system for air combat engagements, Paladin, has been developed. A pilot's job in air combat includes tasks that are largely symbolic. These symbolic tasks are generally performed through the application of experience and training (i.e. knowledge) gathered over years of flying a fighter aircraft. Two such tasks, situation assessment and throttle control, are identified and broken out in Paladin to be handled by specialized knowledge based systems. Knowledge pertaining to these tasks is encoded into rule-bases to provide the foundation for decisions. Paladin uses a custom built inference engine and a partitioned rule-base structure to give these symbolic results in real-time. This paper provides an overview of knowledge-based reasoning systems as a subset of rule-based systems. The knowledge used by Paladin in generating results as well as the system design for real-time execution is discussed

    Flight-test evaluation of STOL control and flight director concepts in a powered-lift aircraft flying curved decelerating approaches

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    Flight tests were carried out to assess the feasibility of piloted steep curved, and decelerating approach profiles in powered lift STOL aircraft. Several STOL control concepts representative of a variety of aircraft were evaluated in conjunction with suitably designed flight directions. The tests were carried out in a real navigation environment, employed special electronic cockpit displays, and included the development of the performance achieved and the control utilization involved in flying 180 deg turning, descending, and decelerating approach profiles to landing. The results suggest that such moderately complex piloted instrument approaches may indeed be feasible from a pilot acceptance point of view, given an acceptable navigation environment. Systems with the capability of those used in this experiment can provide the potential of achieving instrument operations on curved, descending, and decelerating landing approaches to weather minima corresponding to CTOL Category 2 criteria, while also providing a means of realizing more efficient operations during visual flight conditions
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