Advanced Materials Research Vols. 875-877

Abstract: A new approach to information recording in distributed media based on the forced wave excitation involved by temperature fluctuations was proposed. The scheme of the device providing the implementation of the proposed approach is considered.

Abstract: The research environment is a transversely isotropic model, which is characterized with constant physical mechanical properties in different directions in the plane of isotropy, and a different properties in the direction perpendicular to the plane of isotropy. For defining parameters of shear resistance of shale (transversely isotropic model) in three mutually perpendicular directions, it is necessary to prepare 9 (nine) samples, size (8x8x8) [c, using the Mor-Coulomb's law, where the destruction of rock happens in plane of the least resistance to shear. This paper presents results got from tests performed in geomechanical laboratory.

Abstract: The machining parameters for turning of PEEK CF30 using TiN coated tools under dry conditions have been optimized by using Non dominated Sorting Genetic Algorithm (NSGA-II), a non dominated solution set is obtained. The objectives considered are the minimisation of machining force thereby minimising specific cutting pressure as function of the main operating parameters. The results indicated that the minimal cutting parameters are preferred for reducing the machining force, and the minimal cutting speed, medium depth of cut and high feed rate are recommended for minimal specific cutting machining. As per the requirement, the manufacturing engineer should select the proper cutting parameters.

Abstract: Adopting MTS815 hydraulic servo system, through triaxial compressive deformation and triaxial creep experiment result of tunnel supports, research the stress-strain and creep properties of tunnel supports. Test results show that deformation process of support concrete displays obvious strain softening, instantaneous elastic strain increments with stress level and strain of creep curve appears increased trend with time. Creep curve of concrete drive to a fixed value when stress level is lower and strain rate of concrete more and more small. The generalized Kelvin model of three element and LUBBY2 model are feasible as creep model of concrete support. Based on the relation of creep characteristic curves for rock salt, the creep parameters of generalized Kelvin model and LUBBY2 model are advanced.

Abstract: To study catenary characteristics of FAST (Five-hundred-meter Aperture Spherical radio Telescope) tie-down cable, this paper establishes tie-down cable equilibrium differential equation and cable length formula based on catenary theory, analyzes numerical simulation of multi-segment bar element method, and designs an experimental scheme. Taking 1×7 Ø12.7steel cable and Ø10 CFRP (Carbon Fiber Reinforced Polymer) cable for example, we can obtain three results respectively through manners mentioned above, and the agreement among them is excellent. Meanwhile, difference between results and elastic deformation of no-weight cable is not so big that catenary of two cables can be negligible. Further research shows that cable length is more sensitive to catenary than horizontal angle; cable longer deformation will benefit actuator to meet position precision effortlessly, however, stroke and velocity of actuator will increase and initial tension displacement of tie-down cable decrease correspondingly, this alteration should be compensated during reflector surface measuring and controlling; due to chord-tangent angle and tangential force is less than 1.28°and 241.4N, catenary effect on joint pose is weaker; generally speaking, CFRP cable has less catenary problem than steel cable, better mechanics characteristics, but bigger stroke and velocity for actuator and smaller initial tension displacement for tie-down cable. The research will provide references for design of tie-down cable, actuator, joint, and reflector measurement and control.

Abstract: Coordinate Measuring Machine (CMM) is nowadays widely used for a large range of accurate and precise dimensional measurements. The strategy of µ-scale measurement is expected to carry out with ever-increasing performance in term of root error separation for stylus system and CMM machine accuracy. The experimental analysis method in this paper aims to study the effect of dynamic root errors at different undulations per revolution (UPR) response of artifact measurement using selected two types of CMM touch-triggering stylus. Direction of stylus characteristics and stylus speed parameters were adopted and emphasized upon throughout the course of experiment. The results were investigated using Fourier analysis could thus be derived to ensure foreseeable accurate and precise results of CMM machine and stylus errors. Some specific error equations for stylus system and machine responses have been postulated and analysed empirically. The results may also employ validating an experimental investigation to detection accuracy development using PRISMO-Bridge-CMM-type in NIS.

Abstract: Strengthening safety monitoring of bridges during service time and improving the capability of emergency support have become the priority of the development of China’s present transportation system. Strain sensors play a great role in bridge detection and health monitoring system. In order to overcome disadvantages of traditional resistance strain sensors, such as big temperature drift, short life and inadaptability in the environment of low temperature and humidity, new arch strain sensors have been developed. This paper mainly discusses the structural and material characteristics of this sensor, as well as the performance test analysis of this strain sensor.

Abstract: Fiber Reinforced Polymer (FRP) strengthening of structures has been gaining increasing interest, traditionally in application with concrete structures, and more recently in application with steel structures. Because of their unique blend of properties, composites reinforced with high performance fibers find use in many structural applications. This paper defines the effect of FRP layers on behaviour of steel plate. In this regard, some models are selected and tested by rigid frame and actuator. The experimental model is connected to a rigid frame. The FRP layer acts similar to a lateral support for the steel plate, and possesses the intelligent behavior (specified control for establishing of flexural line and further leaning towards post buckling condition), meaning that the FRP layer can lead the local flexural deflection towards the total flexure of the steel plate and effectively contributes more in resisting the shear stresses and extension of post flexure lines in steel plate and formation of composite plate. This is due to involvement of more area of steel plate to resisting of the imposed stresses. Result shows, the FRP layers would increase the stiffness, energy absorption, shear capacity and will be decreasing the ductility of steel plate as compared with composited steel plate with other materials as reinforcement concrete.

Abstract: In this paper, semiconductor simulation software ISE TCAD 10.0 was used to simulate W/SiC SBD forward voltage characteristics and reverse voltage characteristics at different temperatures on the basis of theoretical analysis, and the valuable results were achieved. Under the temperature range from 73 K to 773 K, the simulation results of W/SiC Schottky barrier diode forward voltage characteristics showed that forward characteristics were significant influenced by the temperature. At room temperature (303K), if bias voltage was low, the current will be exponential growing with voltage, and the turn-on voltage of W/SiC Schottky barrier diode was about 0.2V. If bias voltage was high, the current increased will be high, and the series resistance effect will become obvious. Under lower bias (2V), a different temperature from 73K to 573K had small impact on reverse current-voltage characteristics. The results showed that the device had the good rectifier characteristics, small reverse current, high breakdown voltage, and the device can steadily and long-term work in high temperature and other complex environment.

Abstract: ts hard to get ideal ultrathin sections because of the adamant SiO2 dust in silicosis, after perfusion fixation methods and strict control of the cutting speed, improving the success rate of the Silicosis tissue TEM sample preparation of ultrathin sections,so we can more clearly and accurately observed ultrastructural changes of silicosis,and it also can offer morphological basis for research the silicosis organizations function histological changes.