A Study on the Design and Performance of High-altitude Simulation Test System

On the basis of automatic test system of the status in domestic and foreign, by analysis of the various functions and performance of the integrated test system, a design of the integrated test system is proposed, FPGA as the core logic controller of the hardware circuit. The system of the hardware design include: digital signal source output modules, analog output module and PCM codec module. Design of hardware circuit are mainly described. In addition, a detailed analysis of some key technologies in the design process was given. Overall, its data exchange with host computer is through the PCI card, data link and bandwidth can be expanded in accordance with the actual needs. The entire system designed in the modular principle, which has a strong scalability.

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Framework and performance analysis of college English testing system based on data mining technology

Journal of Intelligent & Fuzzy Systems ◽

10.3233/jifs-219152 ◽

2021 ◽

pp. 1-11

Author(s):

Liu Narengerile ◽

Li Di ◽

Keyword(s):

Data Mining ◽

Test System ◽

Test Time ◽

Testing System ◽

Test Results ◽

System Software ◽

Examination System ◽

Mining Technology ◽

College English ◽

And Performance

At present, the college English testing system has become an indispensable system in many universities. However, the English test system is not highly humanized due to problems such as unreasonable framework structure. This paper combines data mining technology to build a college English test framework. The college English test system software based on data mining mainly realizes the computer program to automatically generate test papers, set the test time to automatically judge the test takers’ test results, and give out results on the spot. The test takers log in to complete the test through the test system software. The examination system software solves the functions of printing test papers, arranging invigilation classrooms, invigilating teachers, invigilating process, collecting test papers, scoring and analyzing test papers in traditional examinations. Finally, this paper analyzes the performance of this paper through experimental research. The research results show that the system constructed in this paper has certain practical effects.

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Effect of altitude conditions on combustion and performance of a turbocharged direct-injection diesel engine

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/09544070211026204 ◽

2021 ◽

pp. 095440702110262

Author(s):

Zhentao Liu ◽

Jinlong Liu

Keyword(s):

Diesel Engine ◽

High Altitude ◽

Diesel Engines ◽

Direct Injection ◽

Pressure Rise ◽

Ambient Conditions ◽

Allowable Limit ◽

Spray Formation ◽

Direct Injection Diesel Engine ◽

And Performance

Market globalization necessitates the development of heavy duty diesel engines that can operate at altitudes up to 5000 m without significant performance deterioration. But the current scenario is that existing studies on high altitude effects are still not sufficient or detailed enough to take effective measures. This study applied a single cylinder direct injection diesel engine with simulated boosting pressure to investigate the performance degradation at high altitude, with the aim of adding more knowledge to the literature. Such a research engine was conducted at constant speed and injection strategy but different ambient conditions from sea level to 5000 m in altitude. The results indicated the effects of altitude on engine combustion and performance can be summarized as two aspects. First comes the extended ignition delay at high altitude, which would raise the rate of pressure rise to a point that can exceed the maximum allowable limit and therefore shorten the engine lifespan. The other disadvantage of high-altitude operation is the reduced excess air ratio and gas density inside cylinder. Worsened spray formation and mixture preparation, together with insufficient and late oxidation, would result in reduced engine efficiency, increased emissions, and power loss. The combustion and performance deteriorations were noticeable when the engine was operated above 4000 m in altitude. All these findings support the need for further fundamental investigations of in-cylinder activities of diesel engines working at plateau regions.

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Ground Flutter Simulation Test Based on Reduced Order Modeling of Aerodynamics by CFD/CSD Coupling Method

International Journal of Applied Mechanics ◽

10.1142/s175882511950008x ◽

2019 ◽

Vol 11 (01) ◽

pp. 1950008

Author(s):

Binwen Wang ◽

Xueling Fan

Keyword(s):

Aerodynamic Force ◽

Test System ◽

Simulation Test ◽

Robust Controller ◽

Test Technique ◽

Reduced Order ◽

Aerodynamic Model ◽

Flutter Boundary ◽

Computational Fluid Dynamics Cfd ◽

Good Agreement

Flutter is an aeroelastic phenomenon that may cause severe damage to aircraft. Traditional flutter evaluation methods have many disadvantages (e.g., complex, costly and time-consuming) which could be overcome by ground flutter test technique. In this study, an unsteady aerodynamic model is obtained using computational fluid dynamics (CFD) code according to the procedure of frequency domain aerodynamic calculation. Then, the genetic algorithm (GA) method is adopted to optimize interpolation points for both excitation and response. Furthermore, the minimum-state method is utilized for rational fitting so as to establish an aerodynamic model in time domain. The aerodynamic force is simulated through exciters and the precision of simulation is guaranteed by multi-input and multi-output robust controller. Finally, ground flutter simulation test system is employed to acquire the flutter boundary through response under a range of air speeds. A good agreement is observed for both velocity and frequency of flutter between the test and modeling results.

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Preparation and Performance of Si/Al/C Composites Anode Material Prepared by Glucose-Modified

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.164.268 ◽

2012 ◽

Vol 164 ◽

pp. 268-271

Author(s):

Xu Ma ◽

Ling Long Kong ◽

Yu Ling Liu ◽

Yan Hong Ding ◽

Jie Zhao ◽

...

Keyword(s):

Anode Material ◽

Coulombic Efficiency ◽

Test System ◽

Cycling Stability ◽

Charge Capacity ◽

And Performance ◽

Charge Discharge ◽

Discharge Test

Si/Al/C composites were synthesized by the method of doping aluminum and glucose-modified. The samples were characterized by XRD, SEM, and the capacity and cycling stability of the composites were tested by electrochemical charge/discharge test system. After glucose was pyrolyzed, the first discharge and charge capacity of Si/Al/C composites were 1312 and 956.7mAh/g, and the first coulombic efficiency was 72.9%. After 50 cycles, the capacity of Si/Al/C composites was 440mAh /g and the coulombic efficiency remained over 98.1%

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Design of Integrated Simulation Test System for Ship Platform

10.1145/3469213.3470411 ◽

2021 ◽

Author(s):

Yong Xu ◽

Wenjian Yao ◽

Yuan Qu ◽

Chao Ma

Keyword(s):

Test System ◽

Simulation Test ◽

Integrated Simulation

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Video Scanning Hartmann Optical Testing of State-of-the-Art Parabolic Trough Concentrators

Solar Energy ◽

10.1115/isec2006-99172 ◽

2006 ◽

Cited By ~ 10

Author(s):

Tim Wendelin ◽

Ken May ◽

Randy Gee

Keyword(s):

Technology Development ◽

Scale Up ◽

Test System ◽

Optical Testing ◽

Parabolic Trough ◽

Energy Technologies ◽

Energy Needs ◽

World Energy ◽

Optical Test ◽

And Performance

Significant progress has been made recently in solar parabolic trough technology development and deployment. Part of this success is due to the changing world energy scenario and the recognition that viable renewable energy technologies can play a role in supplying world energy needs. Part is also due to ongoing collaborative efforts by industry and the Department of Energy’s (DOE) Concentrating Solar Power Program (CSP) to enhance the state of the technology in terms of both cost and performance. Currently, there are two trough concentrator projects which the DOE CSP program is supporting. One company, Solargenix, is developing a design to be used in a 64MW plant outside of Boulder City, Nevada. This design is based on the original LUZ LS-2 trough concentrators employed at the Solar Electric Generating Systems (SEGS) plants in Southern California. Another company, Industrial Solar Technology (IST), is working on a scale-up of their design used historically for process heat applications. Very different from the LS-2 approach, this design is still in the research and development stages. One way in which the DOE CSP parabolic trough program assists industry is by providing optical testing and qualification of their concentrator designs. This paper describes the Video Scanning Hartmann Optical Test System (VSHOT) used to optically test both of these designs. The paper also presents the results of tests performed in the past year and what impact the testing has had on the developmental direction of each design.

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