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The mechanical properties of the stent graft are important factors influencing the outcome of TEVAR treatment and the occurrence of postoperative complications. The aim of this study is to improve and design a mechanical performance testing equipment for thoracic aortic stent grafts. The mechanical performance testing equipment consists of a radial force testing equipment of the stent graft designed by the wire compression grip method and a dynamic straightening force testing device with stable and controllable test conditions and continuously variable test angles. By constructing the testing equipment to physically measure the stent specimen, the experimental results reflect the trend of change and the simulation results are basically consistent, i.e. the mechanical properties of the thoracic aortic stent designed in this study is feasible and the measured data are valid. The testing equipment can provide the basis and reference direction for the quality testing of stent graft products, optimisation of mechanical properties of stent grafts and R&D innovation. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced plastic (CFRP) composite materials demonstrate significant promise to further improve weight to performance in automotive engineering. Nevertheless, design of CFRP components for crashworthiness criteria remains rather challenging and typically requires laborious trial-and-error processes. This study aims to promote computational design of CFRP structures by establishing effective constitutive model that is implemented in the commercial finite element code Abaqus/Explicit. Two different numerical models (namely, the single layer shell model and the stacked shell model) were developed to simulate experimental crushing tests on the square CFRP tube. The effects of key parameters for these two FE models were analyzed, respectively. The comparisons of numerical results with experimental data indicated that the 9 layers stacked shell model is capable of reproducing experimental results with relatively higher accuracy. Based on the validated modeling approach, crushing behaviors of several CFRP thin-walled structures with different cross sectional geometries and thicknesses were further explored. The failure modes and key indicators in relation to the structural crashworthiness were investigated for identifying a best possible sectional configuration. It is found that the circular tube shows superior specific energy absorption capacity of all different tubal configurations with the same wall thickness, meaning that the tube with circular section is of good potential as a crashworthy CFRP structure. [ABSTRACT FROM AUTHOR]

The article offers information on several non-destructive testing solutions including the Reddy 96 eddy current array instrument from Eddyfi, the MTN/5000 condition monitoring system from Monitran, and the SVM 3001 Stabinger Viscometer from Anton Paar GmbH.

The detection and diagnosis of faults in industrial processes is a very active field of research due to the reduction in maintenance costs achieved by the implementation of process monitoring algorithms such as Principal Component Analysis, Partial Least Squares or more recently Canonical Variate Analysis (CVA). Typically the condition of rotating machinery is monitored separately using vibration analysis or other specific techniques. Conventional vibration-based condition monitoring techniques are based on the tracking of key features observed in the measured signal. Typically steady-state loading conditions are required to ensure consistency between measurements. In this paper, a technique based on merging process and vibration data is proposed with the objective of improving the detection of mechanical faults in industrial systems working under variable operating conditions. The capabilities of CVA for detection and diagnosis of faults were tested using experimental data acquired from a compressor test rig where different process faults were introduced. Results suggest that the combination of process and vibration data can effectively improve the detectability of mechanical faults in systems working under variable operating conditions. [ABSTRACT FROM AUTHOR]

The article offers information on products used in testing and measurement including the 228A optical wavelength meter from Bristol Instruments Inc., the CAS 140CT-HR spectroadiometer from Instrument Systems GmbH, and the mobile Spectrotest OES analyzer from Spectro Analytical Instruments Inc.

To meet the testing requirements of high speed components used in modern communication systems, in an efficient and cost effective manner, it is necessary to develop new device performance measurement techniques that are easily scalable to high frequencies. Traditional up/down conversion based transmitter testing architectures are sensitive to the linearity of the mixers and carrier phase noise in the receiver. Direct undersampling based test instrumentation can overcome the limitations imposed by mixers in up/down conversion. A major challenge in direct undersampling based test architecture is to achieve precise phase alignment between different components of the test setup. Such phase alignment of high frequency signals requires the use of expensive test instruments adding to the cost and complexity of the overall test system. To resolve this problem, an incoherent undersampling based test method is developed in this research that eliminates the need for precise phase synchronization between the RF test signal carrier, its amplitude-modulated envelope (generally necessary for measuring amplifier nonlinearity) and the reference sampling clock. A side-benefit, due to the use of signal undersampling, is that signal acquisition is achieved without the use of a Nyquist rate data converter. Multiple RF performance metrics are extracted without the use of a reference receiver. The accuracy of the proposed setup is compared against existing coherent sampling based test setups. [ABSTRACT FROM AUTHOR]

Purpose. To compare measures of visual acuity (VA) and contrast sensitivity (CS) from the Thompson Xpert 2000 and MultiQuity (MiQ) devices. Methods. Corrected distance VA (CDVA) and CS were measured in the right eye of 73 subjects, on an established system (Thompson Xpert) and a novel system (MiQ 720). Regression was used to convert MiQ scores into the Thompson scale. Agreement between the converted MiQ and Thompson scores was investigated using standard agreement indices. Test-retest variability for both devices was also investigated, for a separate sample of 24 subjects. Results. For CDVA, agreement was strong between the MiQ and Thomson devices (accuracy = 0.993, precision = 0.889, CCC = 0.883). For CS, agreement was also strong (accuracy = 0.996, precision = 0.911, CCC = 0.907). Agreement was unaffected by demographic variables or by presence/absence of ocular pathology. Test-retest agreement indices for both devices were excellent: in the range 0.88-0.96 for CDVA and in the range 0.90-0.98 for CS. Conclusion. MiQ measurements exhibit strong agreement with corresponding Thomson measurements, and test-retest results are good for both devices. Agreement between the two devices is unaffected by age or ocular pathology. [ABSTRACT FROM AUTHOR]

Olfactometers have been gaining popularity as research tools, but they have yet to replace established testing procedures in a variety of laboratory and clinical settings, including absolute threshold tests. In this research, we designed and operated a simple olfactometer with which to assess threshold. To do this, we used a method-of-adjustment test that was compared to the three-alternative forced choice ascending sniff bottle staircase method, which is currently a standard threshold test procedure. We found that the olfactometer threshold test correlated highly with the staircase method, and that it possessed suitable test-retest reliability. The advantages of the olfactometer threshold test include faster test time and reduced cleaning and reassembly demands. Future use of the olfactometer in olfactory identification and/or detection thresholds amongst odors is also outlined. [ABSTRACT FROM AUTHOR]

The article offers brief information on various equipment used in non-destructive testing and condition monitoring which include the DR3000 radiographic film digitisation technology from CIT UK, the LC15Dx laser scanner from Nikon Metrology Inc., and the X-MET7000 series hand-held analyser from Oxford Instruments PLC.

TSC designs and builds electromagnetic sensor probes for the industrial NDT market. These probes are used for the detection and sizing of surface-breaking cracks in metals and for the determination of stresses in steel. The company expends a great deal of effort in research and development; this R&D typically consists of numerical simulations and the creation of prototype probes. This paper details the research and development of some of the more complex probes TSC has recently created. [ABSTRACT FROM AUTHOR]

Commonly used small creep specimen types (i.e. conventional sub-size uniaxial specimens, impression creep specimens and small punch specimens) and test methods, are briefly described, including their capabilities and the methods used to process the data from these tests. The performances of these test types are compared and their relative advantages and disadvantages, for specific practical applications, are assessed. An alternative, novel, 'more flexible', small ring-type specimen test method is described. A significant advantage of the ring-type specimen is that it has a much greater equivalent gauge length (EGL), compared with those of other small specimen types. This specimen type allows small strains to be related to relatively large deformations; it is particularly suitable for creep tests at relatively low equivalent uniaxial stresses. Possible future exploitation of the small specimen test techniques is briefly addressed. [ABSTRACT FROM AUTHOR]

The article offers reviews on products including JSM-IT100 InTouchScope scanning electron microscope by Jeol Ltd., AMH55 hardness testing system by LECO Corp. and Crystallography Platform D8 Gen 2 by Bruker AXS.

In this paper we describe work we have done in developing an insertable surgical imaging device with multiple degrees of freedom for minimally invasive surgery. The device is fully insertable into the abdomen using standard 12 mm trocars. It consists of a modular camera and lens system which has pan and tilt capability provided by two small DC servo motors. It also has its own integrated lighting system that is part of the camera assembly. Once the camera is inserted into the abdomen, the insertion port is available for additional tooling, motivating the idea of single-port surgery. A third zoom axis has been designed for the camera as well, allowing close-up and faraway imaging of surgical sites with a single camera unit. In animal tests with the device we have performed surgical procedures including cholecystectomy, appendectomy, running (measuring) the bowel, suturing, and nephrectomy. Preliminary tests suggest that the new device may have advantages over a standard laparoscope including the following. ∙Low-cost and simple design. ∙Easier and more intuitive to use than a standard laparoscope. ∙Joystick operation requires no specialized operator training. Pan/tilt functions provide a large imaging volume not restricted by the fulcrum point of standard laparoscope. ∙Time to perform procedures was better than or equivalent to a standard laparoscope. We believe these insertable platforms will be an integral part of future surgical systems. The platforms can be used with tooling as well as imaging devices, allowing many surgical procedures to be performed using such a system. [ABSTRACT FROM AUTHOR]

Abstract: A novel device for obtaining pulling and holding forces for draw bead tooling on inclined binder surfaces has been developed. A mechanical design featuring two load cells, a male–female draw bead set, translation and rotation degrees of freedom, and a screw-driven clamping system has been incorporated into a standard tensile test machine. On a real time basis, pulling force, holding force, and draw-in displacement are downloaded directly into a PC for data processing. Results for the sheet metal materials considered confirm quantitatively that the binder angle significantly influences the draw bead pulling force. For example, for the materials, bead penetrations, and bead geometries studied, the pulling force at a 20° binder angle ranged from 55% to 96% of that corresponding to a 0° binder angle. The pulling force data are useful for the purpose of theoretical and numerical draw bead model calibration. The proposed experimental system, called the Oakland University Angle Draw Bead Simulation (OU-ADBS) test, represents a significant breakthrough in draw bead simulation technology due to its relatively low cost and clever design. [Copyright &y& Elsevier]

The article evaluates two industrial machineries including Plant Condition Monitor (PCM) from Artesis LLP and vibration monitoring and balancing equipments from Schaeffler Ltd.

The article evaluates several non-destructive testing and condition monitoring products including the CSI 300 Machinery Health Monitor, a compact protection system from Emerson Process Management Ltd., the InspectionWorks Connect remote collaboration software from GE Measurement & Control, and the UltraMax thermal imaging technology from FLIR Systems In.

Schiff base prepared from salicylaldehyde and diethylene triamine was ethoxylated by poly (ethylene glycol) of different molecular weights, namely 200, 600, 1000 and 2000, by using β,β-dichlorodiethyl ether as a linking agent. The ethoxylation reaction took place at both ends of the base upon using poly(ethylene glycol) (PEG) 200 and 600, whereas at one end when PEG 1000 and 2000 were used. The chemical structure of the prepared compounds was confirmed by using IR and 1HNMR spectroscopy. Thermodynamic parameters for micellization and adsorption or the prepared compounds were measured based on the surface tension of their solutions at different temperatures. Then, the compounds under investigation were tested as oil spill dispersants according to different standard test methods. It was found that the compounds with lower molecular weights of PEG showed the best dispersancy. [ABSTRACT FROM AUTHOR]

In this paper, a reduced-pin-count-testing technique is presented to control the IEEE-1500 wrapper through the IEEE-1149.1 TAP for scan delay test. By using only the IEEE- 1149.1 TAP control pins as test-access pins and by embedding an on-chip test clock generator, low-cost automated test equipment (ATE) can be efficiently utilized to reduce testing costs. Experiments show the effectiveness of our technique in utilizing the ATE channels and scan delay testing. [ABSTRACT FROM AUTHOR]

A newly released commercial autorefractor, the Shin-Nippon SRW-5000 (Japan), has been found to be valid compared to subjective refraction and repeatable over a wide prescription range. Its binocular open field-of-view allows the accommodative state to be monitored while a natural environment is viewed. In conventional static mode, the device can take up to 45 readings in 1 min using digital image analysis of the reflected retinal image of a measurement ring. Continuous on-line analysis of the ring provides high (up to 60 Hz) temporal resolution of the refractive state to an accuracy of <0.001 D. Pupil size can also be analysed to a resolution of <0.001 mm. The measurement of accommodation and pupil size was relatively unaffected by eccentricity of viewing up to ±10° and instrument focusing inaccuracies of ±5 mm. The resolution properties of the analysis are shown to be ideal for measurement of dynamic accommodation and pupil responses. [ABSTRACT FROM AUTHOR]

A clinical evaluation of the Shin-Nippon SRW-5000 (Japan), a newly released commercial autorefractor, was undertaken to assess its repeatability and validity compared to subjective refraction. Measurements of refractive error were performed on 200 eyes of 100 subjects (aged 24.4 ± 8.0 years) subjectively (non-cycloplegic) by one optometrist and objectively with the SRW-5000 autorefractor by a second. Repeatability was assessed by examining the differences between the seven autorefractor readings taken from each eye and by re-measuring the objective prescription of 50 eyes at a subsequent session. Although the SRW-5000 read slightly more plus than subjective refraction (mean spherical equivalent +0.16 ± 0.44 D), it was found to be highly valid (accurate) compared to subjective refraction and repeatable over the prescription range of +6.50 to -15.00 D examined. The Shin-Nippon SRW-5000 autorefractor is therefore a valuable complement to subjective refraction and as it offers the advantage of a binocular open field-of-view, has a great potential benefit for accommodation research studies. [ABSTRACT FROM AUTHOR]

The Canon Autoref R-1 is an ‘open-field’ autorefractor which has been widely used for research purposes for the past 20 years, but is no longer manufactured. A new autorefractor, the Shin-Nippon SRW-5000, is now available, and if measures using this instrument are shown to be equally accurate and reliable, is likely to replace the R-1. Here we report on the accuracy and reliability (repeatability and reproducibility) of refraction measures in a paediatric population (from 4 to 8 years of age). Subject numbers were 44 for cycloplegic measures and 53 for non-cycloplegic measures. As would be expected, agreement with cycloplegic refraction and reliability were better when SRW-5000 measures were taken using cycloplegia. Repeatability results from the SRW-5000 autorefractor, both with and without cycloplegia were similar to those reported for the Canon R-1. [ABSTRACT FROM AUTHOR]

The article offers information on nondestructive testing equipment and supplies, including the FirstMap corrosion mapping system from Imperium, the Equipment Monitoring System non-contact temperature measurement system from Raytek, and the CR Test Phantom radiographic system qualification unit from Computerised Information Technology Ltd.

The article offers brief information on several nondestructive testing products including GS2020 'EMAT Adaptor' from Sonemat, the Raptor portable ultrasonic imaging flaw detector from NDT Systems Inc., and new SU9000 field emission (FE) scanning electron microscope (SEM) from Hitachi High-Technologies Corp.

The article discusses the instrumentation for vision training (VT) known as the neuro-vision rehabilatator (NVR). An overview of the development of VT that depends on synoptophores and stereoscopes. It highlights modules where the NVR is applied which include the Visual Motor Enhancer (VME), Ocular Vestibular Integrator (OVI), and Dynamic Ocular Motor Processing (DOMP).

The article offers brief information on several products including the RDS Multi-Purpose Survey Meter from James Fisher Inspection & Measurement Services Ltd. (JFIMS), pipeline inspection interlocks from Smith Flow Control Ltd. and the OPK-300N Optimax MultiLite Non-Destructive Testing (NDT) Inspection Kit from Spectronics Corp.

The article offers brief information on several products for non-destructive testing including the Eddycon C eddy current flaw detector from Ultracon-Service LLC, the Olympus UC90 microscope camera from Olympus and the portable eddy current testing system UniWest EV from UniWest.

The article offers information on the ETboxMB portable eddy current instrument for non-destructive testing from Tecnatom.

The article offers information on the FF85 CT computed tomography (CT) inspection system for non-destructive testing (NDT) from.

The article discusses the launch of the MIZ-21C hand-held eddy current instrument from nondestructive testing (NDT) solutions provider Zetec Inc. and outlines the capabilities and features of the product.

The article offers information on the patent-pending pulsed eddy current (PEC) probe from Eddyf Technologies, which is designed to detect corrosion under insulation (CUI) in the presence of galvanised steel cladding.