Advanced Materials Research Vols. 181-182

Abstract: The aim of this study is to find the influence of cutting parameters and tools on surface roughness and dimensional deviation for better production quality in machining 0Cr18Ni12Mo2Cu2 steel. The most important parameters like cutting velocities, depth of cut and feed rate are considered. The experiments designed four types of boring tool rake angle and two types of coolant, and measured surface roughness and radial runout of workpiece with three acclivitous holes. The results showed that the surface integrity of workpiece obtained by 0.16 mm/rev feed rate with rake angle of tool 25o were superior to that obtained by the previous boring processes. Radial runout precision was highest when feed rate and rake angle were 0.13 mm/rev and 23o, respectively. According to experimental results, the rake angle and structure of boring tool were improved.

Abstract: Effective evaluation of traffic conditions is a key issue involved in alleviating freeway congestion, improving operations and estimating travel time. Loop detectors can provide reliable traffic data sources for traffic conditions measurement and monitoring, however, the multiple influencing factors derived from loop data lead to a combined effect which complicates the measurement. Therefore, a novel traffic conditions evaluation method by utilizing Data Envelopment Analysis (DEA) is proposed. The method can devise an overall traffic conditions evaluation based on the multiple performance measures. To illustrate our method, an experimental study was undertaken with dual-loop-detector data from 6 freeway sections for the year 2006, and 5 measures were selected for inclusion in this multivariate analysis to evaluate the traffic conditions. The conclusions indicate the stakeholders can gain new insight into the overall traffic conditions behind multiple performance measures with our method, and the evaluation results is helpful in identifying transportation investment priorities for specific regions and improving resource utilization among competing sectors.

Abstract: Based on the particularity of the fouling in the sewage heat exchanger, proposed a new heat exchanger with on-line hydraulic removing fouling technology, focused on the structure and principle of this heat exchanger, designed and manufactured the experimental prototype, and determined the best scheme based on analyzing the technical and economic feasibility of various irrigation programs. The experimental results shows that keeping each tube washed for one minute with 5m/s and flushing 10 to 20 heat exchange tubes once a time is the feasible program both in technology and economy. That will give a new way of thinking for the sewage heat exchanger using vigorously in the engineering.

Abstract: We propose a novel method for data reduction in gait recognition, called Subblock Complete Two Dimensional Principal Component Analysis (SbC2DPCA). GEIs were divided into smaller sub-images and redundant subblocks were adaptively removed. Complete Two Dimensional Principal Component Analysis (C2DPCA) was then applied to every sub-image directly, to acquire a set of projection sub-vectors for both row and column directions and these were synthesized into whole features for subsequent classification using nearest neighbor classifier. We evaluate the proposed gait recognition method on the CASIA gait database. The experimental results and analysis show the recognition accuracy of SbC2DPCA to be superior to C2DPCA, with C2DPCA being a special case of SbC2DPCA. The novelty of the proposed method lies in the adaptive removal of redundant data while extracting local features. This translates to data reduction with very minimal loss of information, as demonstrated by the remarkable recognition accuracy when subjects change clothing or have a backpack.

Abstract: Based on the particularity of the fouling in the sewage heat exchanger, this paper proposed a new heat exchanger with on-line draw-ring removing fouling technology, focused on the structure and principle of this heat exchanger, designed and manufactured the experimental prototype. After the experiment on this prototype with the scraper-ring mechanism or not for one month, the experimental results show that this heat exchanger has a very perfect removing fouling effect. That will provide a new concept for the broaden use of sewage heat exchanger.

Abstract: An acoustic reconstructing method in prolate spheroidal coordinate system is proposed in this paper. Firstly, the entire acoustic field in prolate spheroidal coordinate system is divided by some infinite domains and every domain has some nodes. Then pressure functions are determined by requiring the assumed-form solution to satisfy the pressure boundary condition at the measured points. Finally, once nodal pressures are specified, the acoustic pressure everywhere is completely determined due to the known pressure function. The efficiency and precision of reconstruction can be significantly enhanced and satisfactory reconstruction can be obtained with relatively few measurements using the new method. The new method proposed in this paper is suitable for the acoustic sources with a characteristic aspect ratio y:z close 1:1 and x at random, which extends the appropriate application domain of traditional acoustic reconstructing method largely.

Abstract: Aimed at characteristics of mass moment of missiles in exo-atmosphere, it’s inferred that 6-DOF mathematical model based on mass moment controlling stabilities on three axes. Considering the problem of harmoniously controlling two moving masses, moving mass based non-linear theorem was used to solve a series of problems met in attitude control system design. In order to weaken the chattering of the system, a saturation function is introduced to substitute for Sign function to improve the variable structure control law so that the chattering can be depressed. The simulation results illustrate the efficiency of this method.

Abstract: Various shape function and weight function of infinite element are researched and summarized into eight methods, and then various infinite element methods can be summarized as general equation, the condition number of which can reflect merits of infinite method. Condition number of various methods versus frequency and the node number are calculated in this paper. Finally, most optimal infinite element method is summed up. The infinite element method [1-12] is among the most successful techniques used to solve boundary-value problems on unbounded domains and whose solutions satisfy some condition at infinity. Two ideas make the infinite element method attractive: the idea of partition and the idea of approximation. The partition idea covers unbounded domains by attaching infinite strips to finite element partitions of bounded domains. More mature versions of infinite element method involved the approximation idea. These ideas make it possible that the finite element/infinite element method yields significantly greater computational efficiency than other methods such as the boundary element method. There have been a large number of infinite element methods, in which some methods have obvious advantages and some methods have fewer advantages. However, there is less research literature about merits of various infinite element methods appear at home and abroad. Thus, condition number of matrix equation is applied to verify merits of various infinite methods in this paper.

Abstract: A novel method named matrix assembly method is proposed for insulating glass sound transmission. Firstly, acoustic principle and boundary condition are applied to form acoustic equations. Using the matrix assembly method, these acoustic equations can be composed a universal procedure with a general format for insulating glass sound transmission. Efficiency and general capability of this novel method are very high. Lastly, universal procedure is used to solve insulating glass in the code for insulating glass of People's Republic of China. Subsequently some very useful conclusions are conducted for insulating glass, which shows that this novel method for insulating glass is feasible. Furthermore, efficiency and general capability of this novel method are high

Abstract: Particle swarm optimization (PSO) is widely used to solve complex optimization problems. However, classical PSO may be trapped in local optima and fails to converge to global optimum. In this paper, the concept of the self particles and the random particles is introduced into classical PSO to keep the particle diversity. All particles are divided into the standard particles, the self particles and the random particles according to special proportion. The feature of the proposed algorithm is analyzed and several testing functions are performed in simulation study. Experimental results show that, the proposed PDPSO algorithm can escape from local minima and significantly enhance the convergence precision.