Applied Mechanics and Materials Vols. 148-149

Abstract: 4J29 is a typical of expansion alloy and used as sealing glass material and structure material in transistors, integrated circuit devices manufacturing industry. This article adopts heat-treatment experiments and single factor optimization method to study the relationships of recrystallization temperature, beforehand deformation and grain sizes on 4J29 alloy; then discusses the reason why the coarse grain phenomena appear and gives technological measures to improve the quality and performance of workpiece

Abstract: Considering the drawbacks exist in the traditional computational methods, we introduce a finite element method to analyze the windage of suspension insulator strings under the effects of dynamic and random wind loads. The windage of suspension insulator strings in the high voltage transmission line and influenced by static and random wind loads are simulated by using the finite element software. The result shows that the windage of suspension insulator strings subjected to the random wind loads is greater than the counterpart obtained through the statics methods.

Abstract: Ti-based bulk metallic glasses with minor addition of Ag, Au or Pt elements were prepared by copper mold casting. The Microstructure of the as-cast samples was examined by TEM. Nanoparticles identified as cubic Pd3Ti with crystal planes of (111), (200), (220) and (311) are observed in all the alloys modified by the minor addition of Ag, Au or Pt. The results revealed that the glassy/nanoparticle composited alloys exhibited high strength about 2000 MPa and plastic strain between 1.5-10% due to the inhibition of propagation of shear band.

Abstract: This paper presented an equivalent circuit simulation model of the cantilevered piezoelectric bimorph energy harvester for predicting the electrical power output of the energy harvester. The alternating voltage in the equivalent circuit model is identified from FE transducer model and the parameters of the resistance, capacitance and inductance in the equivalent circuit model are identified from FE actuator model. To valid the equivalent circuit simulation model, the power output values are compared with those obtained from the coupled piezoelectric-circuit finite element analysis. The results demonstrate the accuracy of the equivalent circuit simulation model.

Abstract: According to the drawback of high cost and complicated circuit and inadequate use of resources in DSP and FPGA structure of textile image processing, an image processing system based on Nios II in FPGA is designed. FPGA is the core of the system.Nios II processor is created in FPGA.Video image is acquired by CCD and processed in FPGA. The result shows that the system has some characteristics of small size, low cost, high integration, high stability and flexibility.

Abstract: To analyze and evaluate IP network, large amounts of raw data measured by different protocol needs to be organized. After the network probes execute protocol issued by RFC, all raw data was stored in distributed network probes. So far system based on TWAMP is hard to find. No more details are described to teach system designers how to collect, store and analyze these data. In this paper two practical mechanisms are introduced. Data collection mechanism mainly focuses on how to effectively store information retrieved from raw TWAMP test packets. Data Analysis mechanism shows how to process raw data and retrieve network metric from these data.

Abstract: A special kind of data is considered in this paper called multimodal data. It has the property that samples in a class are from several separate clusters. Locality Preserving Projection (LPP) can work well with multimodal data due to its locality preserving property. However, the label information is not used to improve the learning performance due to the unsupervised character of LPP. In this paper, we propose a method called Locality Sensitive Semi-Supervised Dimensionality Reduction (semi-LSDR). It takes both the discriminant information and geometry structure into account. Specifically, we construct a between-class graph on labeled samples and a nearest neighbor graph both from the perspective of locality. A directly mapping can be achieved by solving a generalized eigenvalue problem. Effectiveness of the proposed method is showed through simulations with benchmark data sets.

Abstract: With the five-axis grinding machine tool bed as the research object, the maximum deformation region can be found after analyzing the static characteristics in the use of the grinder limit positions. Through free modal analysis and constraint modal analysis, the vibration characteristics of each order of the bed can be seen and a point in the maximum deformation region is selected to carry out the harmonic response analysis to predict the sustainable dynamic characteristic. According to the results of analysis, find out the weak areas in the bed and conduct the weight-lowing optimization on the condition of no reduction of static and dynamic characteristic of the bed. This paper draws the conclusion of reduction of weight of 143.42kg and materials of 7.73%.

Abstract: In the present work the configuration of 3.5 inch hard disk drives disk rotating at 10,000 rpm was modified by attaching a spoiler to reduce windage on HDD rotation. Hard disk drives were analyzed using two models. In one model the attached spoiler was on the front surface of the Head Stack Assembly (HSA) while in the other the attached spoiler was on the back surface of the HSA. Flex is estimated using a hexahedron mesh. The resulting maximum transient structure total deformation is 875 nm at time 4 ms with no attached spoiler and minimum transient structure total deformation is 385 nm at time 2 ms with a spoiler attached to the front surface HSA. Modified 3.5 inch hard disk drives with an attached spoiler on the front surface HSA gave better results than other models.

Abstract: In order to analyze deformation and stress state of round link chain which is generated by driving sprocket for sudden loading or starting moment between the chains during the working conditions, the symmetric penalty function method was utilized in contact-impact interface of LS-DYNA program and the finite element software ANSYS/LS-DYNA was used to carry on 3D nonlinear contact analysis of three round link chains, the curves of stress and deformation with varying time were gained by simulating the process of the instant contact-impact of chains. The results show that the largest stress value is appeared on the contacting curved arm of driven round link chain, the second stress value is connecting round link chain, the least stress value is driving round link chain; it is circular shape of the contact area of round link chains and it is the main reasons of damage that the largest stress and deformation values of impact is caused by instant changing loading when time lasts 0.05s, and the series gradually fluctuation of strength is led to fatigue through finite element analysis software. The symmetric penalty function method of finite elements can provide a theoretical basis and simulation methods for analyzing the round link chain driving in a variety of different working conditions under the conditions of contact-impact.