Advanced Materials Research Vol. 459

Abstract: To study the identical parallel machine scheduling problem with total tardiness objective, an improved discrete differential evolution DDE_VND is presented. The proposed algorithm hybridizes discrete differential evolution (DDE) with variable neighborhood descent (VND) to enhance its local search ability. Moreover, a constructive heuristic MDD is employed to generate an initial solution in the algorithm to accelerate the convergence of the algorithm. At last, the experimental results based on 50 benchmark instances validate the effectiveness of the DDE_VND algorithm

Abstract: Materials science is an interdisciplinary field applying the properties of matter to various areas of science and engineering. This paper is devoted to the study and construction of finitely supported tight multivariate frames of multivariate multi-wavelets. Inparticular, a necessary conditi- on for their existence is obtained to present some feasible idea for designing such MRA tight frames. The characteristics of binary multiscale pseudoframes for subspaces is investigated. The constructi- on of a GMS of Paley-Wiener subspace of is studied. A constructive method for affine multivariate frames based on such a GMS is established.

Abstract: This paper proposed a CAN-bus and stepper motor based yarn feeding control system for tufting carpet machine. Base on requirement of yarn feeding devise control system architecture. Control system adopts the industrial computer as the master platform and user interface, the lower computer consists of yarn feed step motor controller, speed synchrony controller and yarn guiding controller. Design the communication protocol and the control logic. Through establishing control system prototype system to verify the system function, test results show that the design scheme is feasible

Abstract: Materials science is an applied science concerned with the relationship between the struc- ture and properties of materials. Frames have become the focus of active research field, both in the- ory and in applications. In the article, the binary minimum-energy wavelet frames and frame multi- resolution are introduced. A precise exist-ence criterion for minimum-energy frames in terms of an ineqity condition on the Laurent poly-nomial symbols of the filter functions is provided. An explicit formula for designing minimum-energy frames is also established. The sufficient con-dition for the existence of affine pseudoframes is obtained by virtue of a generalized multiresolution analysis. The pyramid decomposition scheme is established based on such a generalized multiresolution structure.

Abstract: The needle bar transverse shifting would likely form the stop mark on the tufted carpet. Focus on this problem, through analysis the change in yarn feeding path and loop pile forming, construct the mathematical model of length change of yarn feeding in path and usage of loop pile forming while needle bar shifting. Base on the mathematical model analysis key influence for yarn feeding path change. The analyze result is useful for yarn feed compensation solution

Abstract: In this article, the notion of orthogonal nonseparable five-variant wavelet packages, whi- ch is the generalization of orthogonal univariate wavelet packages, is introduced. A new approach for constructing the wavelet packages is presented by iteration method as well wavelet frames. The orthogonality properties for five-dimensional wavelet packages are discussed. Three orthogonality formulas concerning these wavelet packages are estabished. A necessary and sufficient condition for the existence of the pyramid decomposition scheme of space is presented.

Abstract: This paper designed a wrist Device which can detect physiological information and save the information data. The information got by device is including Oxygen saturation of blood, Pulse rate and steps. And the device even can distinguish the state of human body between fall and normal activities with 3-axis accelerometer. The equipment designed for family health care and remote healthy care field. The operation of device is so easy to be mastered that the device might have a potential value for the future medical field

Abstract: A new approach to fault diagnosis of gear wear based on Local mean decomposition (LMD) is proposed. Local mean decomposition can adaptively decomposes the vibration signal into a series of product functions (PFs), which is the product of an envelope signal and a frequency modulated signal. LMD is capable of revealing interesting feature embedded in the signal. The experimental examples are conducted to evaluate the effectiveness of the proposed approach. The experimental results provide strong evidence that the performance of the approach based on local mean decomposition is better to extract the fault characteristics of the faulty gear and can effectively diagnose the gear wear fault.

Abstract: The technology to produce micro-holes without recast layer on nickel-based alloy is studied in this work. The holes are firstly drilled with Nd: YAG laser, a millisecond pulsed laser of high power and efficiency. For the reason of thermal effect, however, holes drilled by this laser always have the defect of recast layer, which is a serious problem, especially in the application as aviation and aerospace engine. In order to remove the recast layer, laser parameters are optimized to produce micro-holes with the least recast layer, and then a kind of chemical etching is used to clear the residual recast layer completely.

Abstract: this article deals with the influence of temperature on the output sensitivity of the piezo-resistive pressure sensor. In order to reduce the temperature drift of output for the piezo-resistive pressure sensor, the double Wheatstonce-bridge method is adopted to test the sensor with the ternperature controlled at the range of 300~373 K. Tlre results indicate that the temperature drift of the sensor output can be lowered by over 70% to improve surveying accuracy. Pressure senter is widely applied to many fields of the industry, so its accuracy can directly influence the quality of surveying system. Since the piezo-resistive pressure sensor is mostly made of semiconductor materials, the sensitivity and linearity of silicon sentor will be affected to some extent, among which non- linearity is connected with dopant density, temperature and pressure. In ideal condition, four resistor strips are equal in variables with temperature changing, in this way, electric bridge can keep balance to eliminate the effect of tempereature on the sentor. But it’s not the case in reality, temperature drift of output for the piezo-resistive pressure sensor is unavoidable, so some technical methods should be adopted to control the phenomenon. Temperature drift, playing an important role in affecting the quality and accuracy of sentor, has drawn public concern. Document 2 intrduces how to adjust supply voltage to control temperature drift of output for the piezo-resistive pressure sensor. Document 3 intrduces temperature compensation in the sensitivity of sentor. This article aims at making use of four resistors with negative temperature and Wheatstonce-bridge to reduce temperature drift and improve output accuracy of pressure sentor