Analog/digital testing of loaded boards without dedicated test points

Vibration is an important issue faced by reciprocating piston engines, and is caused by reciprocating inertia forces of the piston set. To reduce the vibration without changing the main structure and size of the original engine, we proposed a novel coaxial balance mechanism design based on a compact unit body. By introducing a second-order balance mass, this mechanism can significantly increase the efficiency of vibration reduction. The proposed mechanism can effectively balance the first-order and second-order inertia forces with the potential of balancing high-order inertia forces. To accurately determine the second-order balance mass, a closed-form method was developed. Simulation results with a single-cylinder piston DK32 engine demonstrate the effectiveness and advantage of the proposed mechanism. At a crankshaft speed of 2350 r/min, compared with the first-order balance device, the average root mean square velocity of the test points on the engine’s cylinder was reduced by 97.31%, and the support reaction force was reduced by 96.54%.

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Experimental Study on Earth Pressure of Corrugated Steel Culvert under High Fill Embankment

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.405-408.1815 ◽

2013 ◽

Vol 405-408 ◽

pp. 1815-1819

Author(s):

Wen Sheng Yu ◽

Zhu Long Li ◽

Xiao Ru Xie ◽

Li Yuan Guo

Keyword(s):

Mechanical Property ◽

Experimental Study ◽

Reinforced Concrete ◽

Concrete Slab ◽

Earth Pressure ◽

Reinforced Concrete Slab ◽

The Earth ◽

Filling Height ◽

Test Points ◽

Better Than

To analyze the earth pressure of corrugated steel culvert under high fill embankment, a field test was taken and the change law was got with the filling height increasing, the force state when geotechnical grilles were laid on the top of corrugated steel culvert was compared to that of reinforced concrete slab culvert. Results show that the pressure on the top of corrugated steel culvert is smaller than that on the external in same level when test points are near to culvert, the values of test points above and below geotechnical grilles are close, and the pressure of corrugated steel culvert is smaller than that of reinforced concrete slab culvert when filling height is above 7.3 m. So analysis indicates corrugated steel culvert spreads the upper load better, the geotechnical grille can reduce the pressure effectively through earth pressure redistribution, and the mechanical property of corrugated steel culvert is better than reinforced concrete slab culvert under high fill embankment.

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The Digital Testing of Undergraduate Students’ Awareness of Business English Vocabulary

10.1109/ot4me53559.2021.9638798 ◽

2021 ◽

Author(s):

Elena Zorina

Keyword(s):

Undergraduate Students ◽

Business English ◽

Digital Testing

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Ride through testing of variable speed drive due to voltage sag types (types I, II and III)

International Journal of Power Electronics and Drive Systems (IJPEDS) ◽

10.11591/ijpeds.v10.i2.pp690-696 ◽

2019 ◽

Vol 10 (2) ◽

pp. 690

Author(s):

Surya Hardi ◽

R. Harahap ◽

S. Ahmad ◽

M. Isa

Keyword(s):

Drop Out ◽

Dropping Out ◽

Voltage Sag ◽

Type I ◽

Voltage Sags ◽

Test Results ◽

Variable Speed ◽

Variable Speed Drives ◽

Standard Curve ◽

Test Points

Variable speed drives (VSDs) are widely used in various applications mainly in process industry need constant rotational speed. It is developed from power electronic components thus saving energy in its operation. Unfortunately it is susceptible against power quality problem for example voltage sags. The VSD may be disruption or drop out when it is supplied by voltage sags and it is determined by sag characteristics. This study is to investigate effect of voltage sags Types I, II and III on VSD through laboratory testing. The voltage sags characteristics are generated from voltage sag generator (Shaffner 2100 EMC). The effects are presented in susceptibility curves in disruption and drop out conditions. The curves resulted are evaluated by standard curve recommended. Test results show that voltage sag Type I cause the VSD disruption only, whereas two types sag other result in the VSD disruption and also drop out. Evaluation results explain a few test points are in operation area for disruption condition whereas test points for dropping out far below the threshold recommended. Hence the VSD has good quality to voltage sags.

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Research on optimizing the fault diagnosis strategy of complex electronic equipment

Computer Science and Information Systems ◽

10.2298/csis1001223w ◽

2010 ◽

Vol 7 (1) ◽

pp. 223-230

Author(s):

Hong-Xia Wang ◽

Xiao-Hui Ye ◽

Liang Wang

Keyword(s):

Test Point ◽

Electronic Equipment ◽

Fault Detection And Isolation ◽

Point Selection ◽

Optimal Test ◽

Test Information ◽

Testing Sequence ◽

Test Point Selection ◽

Global Optimal ◽

Test Points

Diagnosis strategy is a testing sequence of the fault detection and isolation. For the distribution of the electronic equipment, a feasible engineering maintenance method is put forward based on the questions of test point selection and diagnosis strategy. The concepts of local diagnosis strategy and global diagnosis strategy are introduced. From which the local optimal diagnosis strategy is determined when the local optimal test points have been introduced by using the test information entropy, furthermore, the global optimal diagnosis strategy is determined by coalescing the local optimal diagnosis strategies. At last, the validity of the method is illustrated by an example from which the conclusion can be drawn that it is an optimal diagnosis strategy and the complexity of computation can be reduced.

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The influence to source of data for accuracy on digital terrain models (DTM)

Glasnik srpskog geografskog drustva ◽

10.2298/gsgd0501265b ◽

2005 ◽

Vol 85 (1) ◽

pp. 265-280 ◽

Cited By ~ 2

Author(s):

Branislav Bajat ◽

Dragoljub Strbac

Keyword(s):

Data Acquisition ◽

Topographic Maps ◽

Digital Terrain Models ◽

Accuracy Estimation ◽

Gps Technology ◽

Digital Terrain ◽

Terrain Models ◽

Test Points

The overview of the contemporary data acquisition methods for Digital Terrain Models (DTM), as well as the accuracy of data provided by these methods, are given in this article. The procedure of the accuracy estimation for DTM which is produced by digitizing of topographic maps and test points obtained by GPS technology and aerophotogrammetric terrain surveying, is presented.

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Comparison of two neural network approaches to modeling processes in a chemical reactor

Thermal Science ◽

10.2298/tsci19s2583s ◽

2019 ◽

Vol 23 (Suppl. 2) ◽

pp. 583-589 ◽

Cited By ~ 1

Author(s):

Tatiana Shemyakina ◽

Dmitriy Tarkhov ◽

Alexander Vasilyev ◽

Yulia Velichko

Keyword(s):

Neural Network ◽

Shooting Method ◽

Chemical Reactor ◽

Euler Method ◽

Error Functional ◽

Non Linear ◽

Test Points ◽

Linear Differential ◽

Hidden Layer ◽

Network Approaches

In this paper, we conduct the comparative analysis of two neural network approaches to the problem of constructing approximate neural network solutions of non-linear differential equations. The first approach is connected with building a neural network with one hidden layer by minimization of an error functional with regeneration of test points. The second approach is based on a new continuous analog of the shooting method. In the first step of the second method, we apply our modification of the corrected Euler method, and in the second and subsequent steps, we apply our modification of the St?rmer method. We have tested our methods on a boundary value problem for an ODE which describes the processes in the chemical reactor. These methods allowed us to obtain simple formulas for the approximate solution of the problem, but the problem is special because it is highly non-linear and also has ambiguous solutions and vanishing solutions if we change the parameter value.

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Design of Automatic Test Platform for the Gyroscope Group Based on Pertinence Matrix

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.556-562.2567 ◽

2014 ◽

Vol 556-562 ◽

pp. 2567-2570

Author(s):

He Jia Li ◽

Xue Wang ◽

Hai Feng Xu ◽

Cheng Yao ◽

Wen Ju Gao ◽

...

Keyword(s):

Fault Diagnosis ◽

Performance Test ◽

Gun Control ◽

Automatic Test ◽

Optimal Test ◽

Fault Dictionary ◽

Dependency Matrix ◽

Optimal Criterion ◽

Test Platform ◽

Test Points

Aiming the problem of the armored vehicle's gun control system that there are many kinds of internal devices, complex fault reasons ,but no all-around and online fault diagnosis and state inspection mean, The automatic test platform for the gyroscope group with performance test and fault diagnosis for component and circuit is designed .The platform based on dependency matrix and optimal criterion of the maximum failure feature information entropy optimize test points ,choose optimal test points design. Performance test module is created and provides test result information for fault dictionary in fault diagnosis module. Automatic test platform is able to locate the circuit component failure.The platform is tested by actual vehicle experiment, and the results prove the reliability and validity of the platform.

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