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Abstract: The rapid progress of modern manufacturing and inspection technologies has posed stringent requirements on optical techniques for vibration characterization and dynamic testing. Due to its simplicity, accuracy and whole-field characters, laser speckle interferometry has served as one of the major techniques for dynamic measurement. In this paper, a two-step phase shifting method is developed for quantitative speckle phase measurement, which helps to eliminate the specklegrams needed for phase evaluation and facilitate dynamic measurement. Unlike previously reported two-step methods using fringe patterns with known phase shift of π/2, a small unknown phase shift is employed instead in the proposed method, which eliminates the need for phase shifting devices. Further investigation shows that small phase shifts are preferable over large phase shifts in this method. Shearographic experiments conducted have demonstrated the effectiveness of the proposed technique. [Copyright &y& Elsevier]

An 8-week feeding trial was conducted to determine lysine requirement of juvenile yellow catfish ( Pelteobagrus fulvidraco) by feeding formulated diets containing crystalline l-lysine. Six isonitrogenous and isoenergetic diets (405 g kg−1 protein, 18 kJ g−1 gloss energy) containing fish meal together with soybean protein concentrate as protein sources and fish oil together with soybean oil as lipid sources were formulated. Crystalline l-lysine was added into the six diets to acquire lysine concentrations of 17.3, 21.8, 26.0, 31.3, 35.5 and 41.9 g kg−1 dry diets, respectively. Mixture of crystalline amino acid was supplemented to simulate the amino acid profile in muscle of yellow catfish. The results indicated that final body weight (FBW), weight gain (WG), specific growth rate (SGR), feed efficiency (FE) and protein efficiency (PE) increased with the increase in dietary lysine level from 17.3 to 31.3 g kg−1 of diet and then decreased as the dietary lysine levels further increased. No significant difference in survival rate was found among all the dietary treatments. One-slope, quadratic broken-line analysis on the basis of SGR showed that the dietary l-lysine requirement of juvenile yellow catfish was 33.1 g kg−1 of dry diet (83.2 g kg−1 of dietary protein). [ABSTRACT FROM AUTHOR]

Aims To update our previous computerized epidemiological data according to the new taxonomy, we re-evaluated and re-analyzed the data using the current definitions of lower urinary tract symptoms (LUTS) which were approved and published by the ICS in 2002 and 2010 according to patient perception. Further, we divided overactive bladder (OAB) symptoms into OAB dry and OAB wet to assess their prevalence percentages by using the current definitions. Methods OAB syndrome in our computerized database was re-defined as having the following storage symptoms present, that is, frequency, urgency, nocturia, urgency incontinence, or stress urinary incontinence (SUI). The prevalence of OAB syndrome was determined with a different taxonomy for those five storage symptoms either singly or in combination. OAB symptoms which were probably associated with mixed incontinence were either ignored or excluded. Results The prevalence of OAB syndrome varied from 34.76% to 28.33% to 20.95% using different classifications of the above five storage symptoms. The prevalence of OAB wet symptoms increased with advancing age and this finding was consistent with three different definitions. Conclusions The prevalence of OAB using the current definition is slightly higher than the result found in our previous published data using a defective classification system of OAB symptoms. The effects of mixed symptoms and probable misclassification cannot be overlooked because many women with OAB (with or without urgency incontinence) might also have SUI. Neurourol. Urodynam. 31:56-59, 2012. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: To meet the growing demands of the global photovoltaic (PV) industry, preparing large scale and ultra-thin solar wafers becomes one of the key issues. This paper presents the preparatory investigations of slicing solar silicon ingot into wafers by an abrasive electrochemical method based on a multi-wire saw system. The anodic passivation on silicon can be controlled by applying an anodic potential during the mechanical slicing process, which improves the surface integrity and material removal rate remarkably. This new hybrid machining method has no influence on subsequent cleaning of wafers and preparing the solar cells, and the average photoelectric transformation efficiency is >17.5%. [Copyright &y& Elsevier]

Abstract: In the field of Civil Engineering, the evaluation of concrete elasticity modulus relies heavily on traditional strain gauges like electric resistance strain gauge, demec mechanical strain and compressometer. These strain gauges work pretty well but the sample surface preparation and the strain gauge adhesion are tedious and time-consuming. On the other hand, convenient non-destructive testing methods like rebound hammer and ultrasonic pulse velocity have the disadvantage of large data scattering and low reliability. In this paper, we aim to develop a handy, reliable and cost-effective method for concrete property evaluation based on an optical technique called automatic digital image correlation (ADIC), which acts as an optical strain gauge. By incorporating an automatic searching approach, the proposed ADIC greatly expands the convergence range of normal digital image correlation (DIC) algorithms and is able to automatically determine concrete strain in real time without human interaction. After the optical strain gauge is set up, the axial concrete strain as well as the stress–strain curve is plotted in real time when the concrete sample under testing is loaded. The concrete elasticity modulus is then determined from the curve. A series of experiments have been conducted to evaluate the performance of the proposed optical strain gauge. Comparisons are also carried out between the proposed optical strain gauge and traditional strain gauges such as electronic strain gauge, compressometer and demec mechanical strain gauge, which further confirm the accuracy, convenience and reliability of the proposed technique. [ABSTRACT FROM AUTHOR]

Abstract: Infrared thermography is a rapid, non-invasive and full-field technique for non-destructive testing and evaluation (NDT&E). With all the achievements on IR instrumentation and image processing techniques attained, it has been extended far beyond simple hot-spot detection and becomes one of the most promising NDT&E techniques in the last decades. It has achieved increasing acceptance in different sectors include medical imaging, manufacturing component fault detection and buildings diagnostic. However, one limitation of IR thermography is that the testing results are greatly affected by object surface emissivity. Surface with various emissivities may lead to difficult discrimination between area of defect and area with different emissivity. Therefore, many studies have been carried out on eliminating emissivity, for example, the time derivative approach, lock-in processing and differential contrast measurements. In these methods, sequence of themo-data/images are recorded and being processed in order to eliminate differences of emissivity. Another problem of IR thermography is that any obstruction may limit stimulations and imaging which leads to the observation of unclear defect image. To solve this problem, this paper proposes an algorithm based on the principle of computerized tomography which permits the reconstruction of unavailable/partially available temperature distribution of the affected area using the measured surrounding temperature field. In the process, a set of imaginary rays are projected from many different directions across the area. For each ray, integration of the temperature derivatives along the ray is equals to the temperature difference between the boundary points intercepted by the ray. Therefore, a set of linear equations can be established by considering the multiple rays. Each equation expresses the unknown temperature derivatives in the affected area in terms of the measured boundary temperature data. Solution of the set of simultaneous equations yields unknown thermal distribution in the area which needs to be reconstructed. Based on the proposed computerized tomography reconstruction (CTR) technique, deviated temperature data due to missing temperature data hidden by obstacle can be reconstructed. With further development, this technique may have the potential to be applied in the reconstruction of any smooth physical fields like phase information in optical techniques. [Copyright &y& Elsevier]

Abstract: This study reports a novel cell co-culture technique using micro-molding in capillaries (MIMIC) technology that was utilized to observe the transmigration conditions of two types of cells with and without fluidic shear stress. Besides, the gap size of co-culture device could achieve shortest and not mixture. Endothelial cells (ECs) and smooth muscle cells (SMCs) were used in our experiment. In addition, concentrations of two cell are 8000 cells/μL (ECs) and 9000 cells/μL (SMCs), respectively, the shear stress is 7 dyne/cm2, and the isolation distance between two types of cell are 50 and 200 μm. It is found that in the smaller culture space (50 μm) condition, ECs and SMCs would induce mutually, which would further make cell migration; in larger culture space (200 μm) condition, no inducing reaction took place between ECs and SMCs. It will have more advantages in bio-manipulation and tissue repair engineering. [Copyright &y& Elsevier]

Abstract: Shearography has been widely adopted for nondestructive testing and evaluation of various materials, especially in the rubber industry and aerospace industry. It detects flaws and defects by identifying deformation anomalies when the specimen is stressed by a certain means. Conventional stressing methods for shearography include pressurization, mechanical or acoustic loading and vibration excitation. These stressing techniques are favorably applied in various applications. In this study, we propose a novel impulsive thermal stressing method using high-power flash lamps for convenient nondestructive testing and evaluation in both laboratory and industrial environment. The proposed technique employs a high-energy heat flux to excite the specimen and detects the thermal deformation anomaly using a shearographic setup. By incorporating a novel clustering phase extraction method, the movement of the continuously deforming object is obtained using only one single deformed speckle image at each deformed stage, thus enabling both qualitative and quantitative measurement. Experiments conducted on various samples with cracks and debonds demonstrate the practicability of proposed technique for both laboratory and industrial applications. [Copyright &y& Elsevier]

Abstract: Bolts are widely used in industry for joining members together. The behavior and service life of bolted joints depend on several factors including bolt material, dimensions, surface finish, surface coating and thread tolerances. However, the uppermost factor affecting the reliability and durability is the correctness of the clamping force exerted by the bolt. Thus it is very important to monitor the bolt clamping force to ensure a proper preload during assembly process. Each of the available monitoring techniques including torque control, torque-angle control, strain gauged bolt and ultrasound suffers one or more limitations which affect the reliability of measurement. In this paper, we propose an alternative method for direct tension measurement, which utilizes a washer with a white light speckle pattern on its face as an optical force transducer. By measuring the strain of the washer using automatic digital image correlation, the clamping force can be determined. This method, which enables real-time monitoring of clamping force during fastening, has a potential of being used for mass measurement of clamping force in a production environment. Experiments conducted on bolted structures with washers of different sizes have demonstrated the reliability and usefulness of this new approach. [Copyright &y& Elsevier]

Abstract: In this work, the magnetic and microstructural properties of CoPt nanowires are presented as a function of the electrolyte pH and current density during electrodeposition into anodized alumina templates. CoPt nanowires of high aspect ratio have been prepared using electrolyte pH values in the range from 2 to 6. The as-made samples exhibit a face centered cubic (fcc) structure with soft magnetic properties which transform into the face centered tetragonal (fct) L10 phase after thermal treatment. Different pH values of the electrolyte during electrodeposition lead to significantly different microstructures and, therefore, different magnetic properties. The CoPt nanowires prepared at high pH value are composed of fcc nanorods of about 25nm in length. Thermal annealing of these samples leads to a preferred (001) orientation (along the direction perpendicular to the direction of nanowires) which increases with annealing time. On the other hand, the CoPt nanowires prepared at lower pH value are composed of uniform fcc nanograins with the size ∼2−3nm. Magnetization curves for the later sample are virtually identical in both directions indicating an isotropic behavior. [Copyright &y& Elsevier]