The Designing and Wear Simulation of the Wheel Used in Super-High Speed Point Grinding

2011 ◽  
Vol 175 ◽  
pp. 177-182
Author(s):  
Ya Dong Gong ◽  
Yue Ming Liu ◽  
Ting Chao Han ◽  
Jun Cheng
Keyword(s):  
High Precision ◽  
High Speed ◽  
Theoretical Research ◽  
Wear Simulation ◽  
Grinding Parameters ◽  
Specific Shape ◽  
Air Hole

The application of the wheel used in super-high speed point (SHSP) grinding is introduced in detail, depicting the applied rang of the wheel, through designing the wheel body and the layer of CBN in the wheel. The designed principle is inferred according to the specific shape, the grinding productivity is analyzed in the course grinding zone and the finished grinding zone, introducing the angle of course grinding zone, which affects the grinding parameters in SHSP grinding, the value of the angle is designed to be suited to the point grinding, and manufacturing the wheel, introducing the changed state of chip flowing grinding used in the new wheel, the micro-surface of the wheel is observed through microscope, whose the ratio of air hole and the layer of CBN are analyzed, simulating the wear trend of the new wheel, the conclusions about super hard abrasives and wearing are drawn at last, the application of SHSP grinding is related to designing and manufacturing of the wheel, which provides the equipment for realizing high precision and productivity processing and offers the referred basis for the theoretical research.

INVESTIGATION OF THE ABSOLUTENESS OF TIME

2021 ◽  
pp. 51-54
Author(s):  
S. Tiguntsev
Keyword(s):  
High Precision ◽  
Gravitational Potential ◽  
High Speed ◽  
Relativistic Effect ◽  
Theoretical Research ◽  
Clock Frequency ◽  
Positioning Systems ◽  
The Earth ◽  
Flow Of Time ◽  
The Difference

In classical physics, time is considered absolute. It is believed that all processes, regardless of their complexity, do not affect the flow of time The theory of relativity determines that the flow of time for bodies depends both on the speed of movement of bodies and on the magnitude of the gravitational potential. It is believed that time in space orbit passes slower due to the high speed of the spacecraft, and faster due to the lower gravitational potential than on the surface of the Earth. Currently, the dependence of time on the magnitude of the gravitational potential and velocity (relativistic effect) is taken into account in global positioning systems. However, studying the relativistic effect, scientists have made a wrong interpretation of the difference between the clock frequency of an orbiting satellite and the clock frequency on the Earth's surface. All further studies to explain the relativistic effect were carried out according to a similar scenario, that is, only the difference in clock frequencies under conditions of different gravitational potentials was investigated. While conducting theoretical research, I found that the frequency of the signal changes along the way from the satellite to the receiver due to the influence of Earth's gravity. It was found that the readings of two high-precision clocks located at different heights will not differ after any period of time, that is, it is shown that the flow of time does not depend on the gravitational potential. It is proposed to conduct full-scale experiments, during which some high-precision clocks are sent aboard the space station, while others remain in the laboratory on the surface of the earth. It is expected that the readings of the satellite clock will be absolutely identical to the readings of the clock in the Earth laboratory.

Research on Application of 500MPa Water Cutting Composite Material

2017 ◽  
Author(s):  
Shengxiong Xue ◽  
Zhengwen Chen ◽  
Qile Ren ◽  
Caihong Han ◽  
Bo Chen ◽  
...  
Keyword(s):  
High Precision ◽  
High Speed ◽  
Large Scale ◽  
Engineering Application ◽  
Theoretical Research ◽  
Working Pressure ◽  
Technical Requirements ◽  
Test Application ◽  
Water Cutting ◽  
Research On Application

For large scale curved composite components cutting process engineering application, high precision and high speed are basic cutting requirements. This paper proposed to improve the working pressures up to 500MPa as high-end water cutting working condition. Mathematical model was established based on lots of complicated tests, and cutting mechanism with the aim of ultra-high pressure water cutting processing center equipment reliability was designed. Through the test application examples, it is showed that high precision and high speed water cutting composite components are corresponding to reliable water cutting processing operation. The theoretical research, structural design, test application of the project in this paper was well adapted to the high technical requirements for composite craft wing processing. It can be seen that it is very important to improve the working pressure to reach high precision and high speed composite components processing under the premise of reliable operation.

scholarly journals Variable step control to improve scanning speed of gene sequencing stage

2021 ◽  
pp. 002029402110022
Author(s):  
Xiaohua Zhou ◽  
Jianbin Zheng ◽  
Xiaoming Wang ◽  
Wenda Niu ◽  
Tongjian Guo
Keyword(s):  
Motion Control ◽  
High Precision ◽  
High Speed ◽  
Stable State ◽  
Gene Sequencing ◽  
Scanning Speed ◽  
Settling Time ◽  
Step Motion ◽  
Variable Step ◽  
Step Control

High-speed scanning is a huge challenge to the motion control of step-scanning gene sequencing stage. The stage should achieve high-precision position stability with minimal settling time for each step. The existing step-scanning scheme usually bases on fixed-step motion control, which has limited means to reduce the time cost of approaching the desired position and keeping high-precision position stability. In this work, we focus on shortening the settling time of stepping motion and propose a novel variable step control method to increase the scanning speed of gene sequencing stage. Specifically, the variable step control stabilizes the stage at any position in a steady-state interval rather than the desired position on each step, so that reduces the settling time. The resulting step-length error is compensated in the next acceleration and deceleration process of stepping to avoid the accumulation of errors. We explicitly described the working process of the step-scanning gene sequencer and designed the PID control structure used in the variable step control for the gene sequencing stage. The simulation was performed to check the performance and stability of the variable step control. Under the conditions of the variable step control where the IMA6000 gene sequencer prototype was evaluated extensively. The experimental results show that the real gene sequencer can step 1.54 mm in 50 ms period, and maintain a high-precision stable state less than 30 nm standard deviation in the following 10 ms period. The proposed method performs well on the gene sequencing stage.

scholarly journals Identification of Sleeper Support Conditions Using Mechanical Model Supported Data-Driven Approach

Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3609
Author(s):  
Mykola Sysyn ◽  
Michal Przybylowicz ◽  
Olga Nabochenko ◽  
Lei Kou
Keyword(s):  
High Speed ◽  
Experimental Studies ◽  
Dynamic Interaction ◽  
Theoretical Research ◽  
Rolling Stock ◽  
Monitoring Methods ◽  
Beam Dynamic ◽  
Track Geometry ◽  
Data Driven Approach ◽  
Support Conditions

The ballasted track superstructure is characterized by a relative quick deterioration of track geometry due to ballast settlements and the accumulation of sleeper voids. The track zones with the sleeper voids differ from the geometrical irregularities with increased dynamic loading, high vibration, and unfavorable ballast-bed and sleeper contact conditions. This causes the accelerated growth of the inhomogeneous settlements, resulting in maintenance-expensive local instabilities that influence transportation reliability and availability. The recent identification and evaluation of the sleeper support conditions using track-side and on-board monitoring methods can help planning prevention activities to avoid or delay the development of local instabilities such as ballast breakdown, white spots, subgrade defects, etc. The paper presents theoretical and experimental studies that are directed at the development of the methods for sleeper support identification. The distinctive features of the dynamic behavior in the void zone compared to the equivalent geometrical irregularity are identified by numeric simulation using a three-beam dynamic model, taking into account superstructure and rolling stock dynamic interaction. The spectral features in time domain in scalograms and scattergrams are analyzed. Additionally, the theoretical research enabled to determine the similarities and differences of the dynamic interaction from the viewpoint of track-side and on-board measurements. The method of experimental investigation is presented by multipoint track-side measurements of rail-dynamic displacements using high-speed video records and digital imaging correlation (DIC) methods. The method is used to collect the statistical information from different-extent voided zones and the corresponding reference zones without voids. The applied machine learning methods enable the exact recent void identification using the wavelet scattering feature extraction from track-side measurements. A case study of the method application for an on-board measurement shows the moderate results of the recent void identification as well as the potential ways of its improvement.

High-speed and high-precision fluorescence-based cell count and viability assays using the Cellaca™ MX high-throughput cell counter

Cytotherapy ◽  
2021 ◽  
Vol 23 (5) ◽  
pp. S97
Author(s):  
J. Bell ◽  
Y. Huang ◽  
S. Yung ◽  
H. Qazi ◽  
C. Hernandez ◽  
...  
Keyword(s):  
Cell Count ◽  
High Precision ◽  
High Throughput ◽  
High Speed ◽  
Cell Counter
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