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The powder sintering process is adopted for preparing the porous Cu-35Ni-15Al alloy.The microstructure was observed by using scanning electron microscopy. Mechanical properties were tested and compared at different temperatures and stress conditions. This thesis also studied the impact of stress on creep properties of Cu-35Ni-15Al alloy,The results show there are roughly three deformation stages of high temperature compression deformation.The microscopic deformation was mainly the curved, collapsed and folded holes.The creep resistance performance of porous Cu-35Ni-15Al alloys weakens with the increasing pressure.

The micro-vibrations caused by CMG (Control Moment Gyroscope) can seriously degrade the pointing accuracy and imaging quality of spacecraft. To test the micro-vibrations generated by CMG and obtain the corresponding frequency spectrum characteristics is the key to design the vibration restraining and analyze the vibration transfer properties. In order to simulate the actual installation boundary of CMG on spacecraft, a flexible interface is designed to compare with the rigid interface in traditional testing methods. The results show that: due to the existence of coupling effect between the CMG structure and the flexible interface, the traditional rigid interface is unable to predict the disturbance emitted by CMG in the installation boundary of spacecraft accurately. To study the micro-vibrations produced by CMG in the installation boundary of flexible interface is of great significance.

Multiple-scale community of complex networks has attracted much attention. For the problem, previous methods can not investigate multiple-scale property of community. To address this, we propose a novel algorithm (h_LPA) to detect multiple-scale structure of community. The algorithm is a heuristic label propagation algorithm associated with spectral analysis of complex networks. Label updating strategy of h_LPA is combined with heuristic function from the perspective of networks dynamics. The heuristic function further improves the dynamic efficiency of h_LPA. Extensive tests on artificial networks and real world networks give excellent results.

Modern aircraft structures need to be further integrated and parts to be enlarged, the structural parts which require high accuracy of size, shape, and good deformed surface finish, so digital machining process has become key technology in aviation industry. Machining parameters selection is an important phase of machining process, it has very important influence on the dimensional quality of an aircraft structural part. This paper develops a methodology to get an optimal machining parameters in an aircraft structural part machining process, which can satisfies the quality specifications and minimizes the expected value of the sum of machining costs at the same time. An engineered-based model is adopted to describe the machining process of aircraft structural part firstly and then a quantitative machining parameter evaluation methods driven by cost constraint is proposed, an optimal machining parameter is obtained through a computer experiment model which can explore a large number of machining process parameter alternatives. At last, we illustrate the validity and the significance of the engineered-based machining parameters analysis method for aircraft structural parts by a case study. The results have shown that the proposed method could significantly increase the efficiency of aircraft structural parts machining process.

A new composite reservoir simulation model of lower computation cost was used to optimize hydraulic fracture length and fracture conductivity during performing a hydraulic fracturing. The simulation model is divided into inner part and outer part. The inner part is dual-porosity and dual-permeability system, and the other is single porosity system. The research shows that the natural fracture permeability and density are the most influential parameters; a relative long fracture with high hydraulic fracture conductivity is required for a high production rate due to non-Darcy flow effects. A shorter primary fracture is better in a gas reservoir of high natural density. The composite model represents the flow characteristic more accurately and provides the optimal design of fracturing treatments to obtain an economic gas production.

Least squares support vector machine (LS-SVM) has an outstanding advantage of lower computational complexity than that of standard support vector machines. Its shortcomings are the loss of sparseness and robustness. Thus it usually results in slow testing speed and poor generalization performance. In this paper, a least squares support vector machine with L1 penalty (L1-LS-SVM) is proposed to deal with above shortcomings. A minimum of 1-norm based object function is chosen to get the sparse and robust solution based on the idea of basis pursuit (BP) in the whole feasibility region. Some UCI datasets are used to demonstrate the effectiveness of this model. The experimental results show that L1-LS-SVM can obtain a small number of support vectors and improve the generalization ability of LS-SVM.

Here we report the photocatalytic degradation characteristics of Rhodamine B in the presence of Cr(VI). Some interesting results were observed during the photocatalytic process. Cr(VI) caused a deactivation effect on the catalyst due to the formation of Cr(OH)3precipitate blocking the active sites of catalyst. Moreover, a kind of red oligomer precipitate was found during the RhB degradation when Cr(VI) was presented. This precipitate was rarely reported in photocatalytic system.

As head-disk clearance has been reduced to nearly 1 nm, air bearing slider dynamic stability becomes increasingly important. This paper presents an experimental study about the coupling effects of Head Gimbal Assembly (HGA) dynamics and arm vibration on Head Disk Interaction (HDI). HDI dynamics was evaluated on a disc with defect. It was found that a much bigger vibration of the slider was observed when suspension local bending mode and arm bending mode are closed to each other than the situation that the two modes are separated. It is proved that both HGA and arm are related to HDI dynamics in a hard disc drive. This study is helpful to characterize system dynamics for robust HDI design.

This paper presents an investigation of spacing fluctuation characterization (SFC) of Hard Disk Drive (HDD) using thermal asperity (TA) sensor. Firstly, the spacing fluctuation monitored by TA sensor is correlated with that monitored by a Laser Doppler Vibrometer (LDV). Secondly, a series of experiments are conducted to study the factors affecting the spacing fluctuation, including disk distortion, head crown sensitivity, ZH sensitivity. Good disk assembly and small crown sensitivity and ZH sensitivity will be helpful to reduce spacing fluctuation.

In this paper the network advertising player is introduced. It can update the contents conveniently. The Kind-Arm 6410 development board is used as the display of the player. In one PC, the HTTPD server is set and the control interface is set in another. Firstly, the user logs into the background web interface, chooses the files and sends to the server through the socket network. Then the file is sent to the development board by the server. On the board it is decoded by the mplayer and displayed on the screen.

The main idea of this paper is to calculate the entire process capability of the Complex Product Machining Process (CPMP) based on modified tradition process capability index and then further decide the improvement orientation and size to individual process parameter through sensitivity analysis. We illustrate the method by a three-stage machining process. The results have shown that the proposed method could significantly improve the process capability.

The reinforcement rib design is one of the key parts in entire bottle design. This paper presents the rib performance prediction system based on the BP algorithm and the finite element analysis, which adopts the finite element analysis results as its learning samples, sets up the rib performance prediction system with BP artificial neural network. The results show that the artificial neural network plays an important role in rib performance prediction; meanwhile it can guide the bottle design in practical terms.

Travel time reliability, as a measure of performance, is attracting more and more attention because unreliable transportation information hinders travelers’ decision making and creates difficulties for authorities to manage network operations. Since travel time reliability is closely related to the stochastic properties of the day-to-day travel time distribution, several statistical measures have been proposed, including standard deviation, coefficient of variation, buffer index, misery index and so on. Each of these measures is derived from travel time distribution but captures only one or two characteristics of travel time. In this paper, an effort is made to evaluate travel time reliability incorporating as many characteristics of travel time as possible based on fuzzy logic. The basic rules are: (1) the larger the variance is, the more unreliable the travel time is; (2) the larger the travel times of unlucky travelers are, the more unreliable the travel time is; (3) the larger the distribution skews to the left, the more unreliable the travel time is. The proposed methodology has been tested and analyzed with field data.

Aiming at the upgrading project of the structural health monitoring system of Jiangyin Bridge, the moving specialty parameters such as the vertical displacement, corner joints, and the synchronization of the two sides of the bridge expansion joint are monitored and acquired by the means of the long real-time health monitoring technology. Based on a large number of measured data, the temperature-dependent regression equation between the movements and the structure temperatures of the bridge expansion joint is established, which could provide much quantitative support and scientific guidance for the daily management and maintenance of the expansion joints.

the reinforcement rib design is one of the key parts in entire bottle design. This paper presents the optimal design of reinforcement rib is based on the orthogonal test and finite element analysis, which is according to the finite element analysis results as its test data, with the target of the minimum stress, analyses the influence of each size of the reinforcement rib on the stress, obtain the optimal design proposal. The results show that the orthogonal experiment method can effectively distinguish different influence of various parameters on the stress, analyze the optimal design proposal, meanwhile, it can guide the bottle design in practical terms.