A novel variable force ratio test system for force measurement

Measurements enabling the online monitoring of the abrasive waterjet (AWJ) cutting process are still under development. This paper presents an experimental method which can be applicable for the evaluation of the AWJ cutting quality through the measurement of forces during the cutting process. The force measuring device developed and patented by our team has been used for measurement on several metal materials. The results show the dependence of the cutting to deformation force ratio on the relative traverse speed. Thus, the force data may help with a better understanding the interaction between the abrasive jet and the material, simultaneously impacting the improvement of both the theoretical and empirical models. The advanced models could substantially improve the selection of suitable parameters for AWJ cutting, milling or turning with the desired quality of product at the end of the process. Nevertheless, it is also presented that force measurements may detect some undesired effects, e.g., not fully penetrated material and/or some product distortions. In the case of a proper designing of the measuring device, the force measurement can be applied in the online monitoring of the cutting process and its continuous control.

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Study on Wheel/Rail Interaction Force Real-Time Monitoring Method Based on Piezoelectric Sensing Technology

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.79-82.7 ◽

2009 ◽

Vol 79-82 ◽

pp. 7-10 ◽

Cited By ~ 1

Author(s):

Ying Song ◽

Yan Liang Du ◽

Bao Chen Sun

Keyword(s):

High Speed ◽

Force Measurement ◽

Interaction Force ◽

Test System ◽

Contact Forces ◽

Strain Gauges ◽

Strain Sensing ◽

Monitoring Method ◽

Sensing Technology ◽

Test Requirements

Measurement of wheel/rail contact forces is of importance. Traditional methods for wheel/rail interaction force measurement all need strain gauges on wheel sets and/or rails. Because strain gauges have the performances of zero-drift, poor anti-interference property and instability of test system, they can’t meet wheel/rail force test requirements in high-speed and heavy haul railways. A new method based on PVDF piezoelectric sensing technology is presented for the test of vertical and horizontal wheel/rail force in this paper. Firstly, based on the wheel/rail interaction characteristics, the restriction condition of track and strain sensing principle of PVDF films, principle for measuring vertical and lateral wheel/rail interaction forces is proposed. Then a series of tests were carried out to compare the performance of PVDF strain sensors with the one of strain gauges. The results show that the PVDF strain sensor has better reliability in wheel/rail force monitoring. Finally numerical analysis by Finite Element Method has been carried out to verify the feasibility of the method presented in this paper.

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Experimental Study of Superfinishing

10.1115/imece1999-0699 ◽

1999 ◽

Author(s):

Shih-Hsiang Chang ◽

Thomas N. Farris ◽

Srinivasan Chandrasekar

Keyword(s):

Experimental Study ◽

Specific Energy ◽

Force Measurement ◽

Removal Rate ◽

Industrial Applications ◽

Sharp Transition ◽

Force Ratio ◽

Force Measurement System ◽

Regime Map ◽

Abrasive Stone

Abstract An experimental study has been made of the superfinishing process. A force measurement system, developed for external cylindrical superfinishing, has been used to directly measure the forces acting on the abrasive stone. A systematic parametric study of material removal rate, force ratio, specific energy and surface finish is detailed. The force ratio and specific energy are found to be sensitive indicators of the cutting action of the stone. This indicates that the force ratio could be used to monitor the process, online in industrial applications. The two regimes of rough finishing and fine finishing have been characterized. A sharp transition from fine to rough finishing occurs at a stone oscillation frequency of about 1600 cpm. This characteristic frequency is mostly independent of stone-work contact pressure. The experimental data is used to construct a superfinishing process map, analogous to the wear-regime map, to depict the various regimes in which different modes of superfinishing dominate.

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Mechatronic System for Impact Tests for Aero Structures

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.198.366 ◽

2013 ◽

Vol 198 ◽

pp. 366-371 ◽

Cited By ~ 6

Author(s):

Andrzej Zbrowski ◽

Andrzej Majcher

Keyword(s):

Impact Force ◽

Force Measurement ◽

Experimental Tests ◽

Test System ◽

Solid Object ◽

Mechatronic System ◽

Energy Parameters ◽

Impact Tests ◽

Measurement Path ◽

The Impact

The article presents the structure of the developed pneumatic propellant system for impact tests particularly conducted in the aviation. The solution is intended for the realization of experimental tests enabling the simulation and recreation of the event of collision of the aircraft, or other means of transport, with the solid object or a bird in motion. The projectile thrower has been designed in form of a 250 mm pneumatic cannon. The size and the energy parameters of the cannon enable the objects weighing several kilograms to be thrown with the speed reflecting the actual collision of the aircraft with a big bird, both in the areas of subsonic and supersonic crash speed. In order for the complex realisation of the impact tests, the structure of the test system for impact tests with the option to record the event by means of a synchronised vision path and an impact force measurement path, has been developed.

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Infrared Temperature Law and Deformation Monitoring of Layered Bedding Rock Slope under Static Load

Advances in Civil Engineering ◽

10.1155/2020/8818278 ◽

2020 ◽

Vol 2020 ◽

pp. 1-16

Author(s):

Zhigang Tao ◽

Kuiming Liu ◽

Xuebin Cui ◽

Xiaobing Qiao ◽

Xiaoming Sun

Keyword(s):

Large Scale ◽

Rock Slope ◽

Test System ◽

Deformation Monitoring ◽

Open Pit ◽

Ratio Test ◽

Layered Rock ◽

Monitoring Process ◽

The Stability ◽

Bedded Rock

China is a mountainous and hilly country with frequent large-scale landslides with complicated mechanisms and serious damage. The layered rock slopes have the worst stability, undergo the most serious damage, and have been rarely investigated due to limitations of measurement methods and instruments. Taking the Nanfen open-pit iron mine as an example, a physical large-model similarity ratio test system is used to simulate the landslide remote monitoring process. The development of the sliding surface, stress-strain characteristics, and infrared law of the bedded rock slope are analyzed. Results show that the anchor cable with constant resistance and large deformation plays a significant role in the stability of the slope, and its maximum slip force is 420 N and 630 N, respectively. Slip and crack are the main mechanisms of energy release in layered rock slope. Some scheme improvement measures for this kind of test are put forward, which provides basis and optimization scheme for the subsequent study of layered rock slope.

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Immunogold labeling of CMP-KDO synthetase produced by recombinant E. Coli cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100128900 ◽

1987 ◽

Vol 45 ◽

pp. 924-925

Author(s):

F. A. Durum ◽

R. G. Goldman ◽

T. J. Bolling ◽

M. F. Miller

Keyword(s):

Inclusion Bodies ◽

Large Scale ◽

Recombinant Dna ◽

Test System ◽

Cell Protein ◽

Gram Negative Bacteria ◽

Cytoplasmic Inclusions ◽

Isolation And Purification ◽

E Coli ◽

Low Concentrations

CMP-KDO synthetase (CKS) is an enzyme which plays a key role in the synthesis of LPS, an outer membrane component unique to gram negative bacteria. CKS activates KDO to CMP-KDO for incorporation into LPS. The enzyme is normally present in low concentrations (0.02% of total cell protein) which makes it difficult to perform large scale isolation and purification. Recently, the gene for CKS from E. coli was cloned and various recombinant DNA constructs overproducing CKS several thousandfold (unpublished data) were derived. Interestingly, no cytoplasmic inclusions of overproduced CKS were observed by EM (Fig. 1) which is in contrast to other reports of large proteinaceous inclusion bodies in various overproducing recombinant strains. The present immunocytochemical study was undertaken to localize CKS in these cells.Immune labeling conditions were first optimized using a previously described cell-free test system. Briefly, this involves soaking small blocks of polymerized bovine serum albumin in purified CKS antigen and subjecting them to various fixation, embedding and immunochemical conditions.

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Real Ear Sound Pressure Levels Developed by Three Portable Stereo System Earphones

American Journal of Audiology ◽

10.1044/1059-0889.0104.52 ◽

1992 ◽

Vol 1 (4) ◽

pp. 52-55 ◽

Cited By ~ 4

Author(s):

Gail L. MacLean ◽

Andrew Stuart ◽

Robert Stenstrom

Keyword(s):

High Frequency ◽

Sound Pressure ◽

Low Frequency ◽

Test System ◽

Output Frequency ◽

Frequency Effects ◽

Adult Men ◽

Frequency Responses ◽

Significant Difference ◽

Sound Pressure Levels

Differences in real ear sound pressure levels (SPLs) with three portable stereo system (PSS) earphones (supraaural [Sony Model MDR-44], semiaural [Sony Model MDR-A15L], and insert [Sony Model MDR-E225]) were investigated. Twelve adult men served as subjects. Frequency response, high frequency average (HFA) output, peak output, peak output frequency, and overall RMS output for each PSS earphone were obtained with a probe tube microphone system (Fonix 6500 Hearing Aid Test System). Results indicated a significant difference in mean RMS outputs with nonsignificant differences in mean HFA outputs, peak outputs, and peak output frequencies among PSS earphones. Differences in mean overall RMS outputs were attributed to differences in low-frequency effects that were observed among the frequency responses of the three PSS earphones. It is suggested that one cannot assume equivalent real ear SPLs, with equivalent inputs, among different styles of PSS earphones.

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