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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.

SnO2 nanocrystalline thin films (NCTFs) with high quality and low infrared emissivity were synthesized through a simple hydrothermal process designed by orthogonal design theory. The microstructure, morphology, photoluminescence (PL) property and the infrared emissivity (IRE) property of as-prepared products were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), fluorescence spectrophotometer, and infrared spectroradio meter (ISM) respectively. The results show that two emission peaks are observed in PL spectra, which can be deconvoluted by Gaussian profile fitting into four emission peaks centered at about 380, 420, 460 and 520 nm respectively. The influences of crystallinity, concentration of particles and resistivity on IRE were systematically investigated, revealing that the better crystallinity, higher particle density and better conductivity are favorable for lowering IRE.

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.

This paper introduces the origin of situation awareness and its application in many fields. Through the analysis the application results in other fields, we conclude that the situation awareness technology can be applied to power system analysis, monitoring distribution operation, disaster warning and so on. It is an indispensable part of the smart grid implementation.

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.

Based on the peck formula, this paper has analyzed measured data of ground surface subsidence, and get the regression curve of ground surface subsidence. Expression for degree of reliability of the maximum ground surface settlement is derived analytically by using central-point method. On the basis of a certain section of tunnel of Guangzhou subway constructed by mining excavation method, linear regression method can be effectively fitting the ground surface deformation data due to tunnel excavation. The central-point method provides a new way for reliability analysis of the ground surface settlement of shield construction.

Aircraft manufacturing process normally requires very high precision assembly parts which are achieved in practice by a high-precision machining parts followed by a high coordination degree assembly process. The current practice in aircraft parts manufacturing process is that the manufacturing cycle is long, the rework rate is high and the manufacturing precision is difficult to improve. This can be sometimes infeasible or very costly. In this paper, we consider a fit degree calculation method to achieve precision aircraft parts with economical manufacturing processes. We consider an analytical approach to establish a physical process model to guide the design and machining process of assembly parts, which can assume the fit degree. The results show that the approach can obtain the nearly optimal process parameters at designated fit degree. At last, a case is developed to verify the proposed methods.

Volcanic rocks of Yixian Formation were widely distributed in western Liaoning. The Yixian volcanic cycle of early Cretaceous in the Chaoyang basin can be divided into two subcycles. The first subcycle is composed of basalt, basalt andesite and andesite. The second subcycle is composed of trachyandensite and trachyte. The volcanic rocks are characterized by high SiO2, Al2O3, K2O and Na2O, and comparatively low TiO2 components. The volcanic rocks are obviously enriched in incompatible elements, and depleted in compatible elements. The ∑REE of volcanic rocks is high and rich in LREE. The spider patterns are the right-incline, there is a slight low Eu negative abnormality and low Ce negative abnormality. The characteristics show that volcanic rocks of Yixian Formation belong to the high-K calc-alkaline magmatic serious. Comprehensive study shows that the volcanic rocks of Yixian Formation were generated in response to lithosphere extension in the continent intraplate orogenic belt.

The work in this paper will present a developed methodology for process capability evaluation and improvement in a multistep machining process. In this methodology, a physical model is developed to describe the complex variation propagation process throughout all steps in a multistep machining process. Then building on this physical model, a process capability index evaluation method is derived. A capability improvement procedure is developed to prioritize process improvement efforts based on the sensitivity analysis of process parameters. Finally, the effectiveness of the proposed methodology is demonstrated in a case study.

According to the characteristics of ship dynamic positioning system, internal model controller is presented based on the mathematical model of ship dynamic positioning system. First, first-order internal model controller is designed in the surge motion. Then, aiming at the coupling characteristics on the movement of sway and yaw, decoupling internal model controller is designed. Simulation results show that the designed controller is effective for the dynamic positioning of ships.

In a multistage machining process, due to the variation accumulation and interaction between different machining stages, variation analysis and diagnosis for quality-related problems become complicated. In this paper, a fault analysis and prediction method is proposed for connecting engineering design with the activities of process variation sources modeling, dimensional variation analysis, and statistical estimate of variations source. Furthermore, a hypothesis testing method is introduced to determine whether each of potential process faults exists in terms of the statistical significance. At last, an experimental study is provided to illustrate the validity and the significance of the proposed methodology.

This paper presents a novel topology and the coordinating control strategy of the hybrid cascade energy storage and bi-directional power regulation device. First, the voltage gain and power transmission characteristics of isolated half-bridge DC/DC converter have been analyzed. On this basis, the coordinating control strategy of the two kinds of converters is mainly studied. Finally, a detailed bi-directional power regulation device model is established on a PSCAD/EMTDC platform.

Densified biomass pellets named as H/S-BPs were prepared from waste wood sawdust (S) in the presence of water hyacinth fiber (H) as solid bridge under room temperature and 6 MPa lower than in the previous study. Mechanical properties including relaxed density (ρr), resiliency (R), abrasion resistance (AR) and impact resistance index (IRI) were evaluated. Results showed that adding H greatly reduced negative effect of resiliency on the mechanical properties of H/S-BPs during storage. For example, H/S-BPs compressed at 6 MPa in an H/S mass ratio of 1 to 3 presented lower resiliency of 10% and higher relaxed density of 1.04 kg dm-3 than pellets without H fiber. This is due to the intertwining action of H fiber, what fabricates solid bridge, replacing the bonding creating by applying high pressure to resist the disruptive force caused by elastic recovery. Thus, compression of waste H and S in a mass ratio of 1 to 3 at room temperature under 6 MPa is a cost-effective process to produce densified sustainable bio-fuel pellet as well as dispose waste S and H, combining the economical and environmental benefits.

A large number of Chinese herbs residues were produced during the production of honeysuckle and midday tea. Usually, the content of organic components in the residues was at a high level. These residues would pose a great threat to the local water environment, if they were not treated and disposed properly. In this paper, a self-prepared anaerobic reactor was utilized to treat the residues of honeysuckle and midday tea in semi-solid phase media. The anaerobic sludge was inoculated into the residues for anaerobic digestion at the temperature of 37±1°C, and ISRs (ISRs is the total solid mass ratio between inoculum and substrate) were 1:2, 1:1, 2:1 respectively. The result showed that the ultimate maximum yield of methane was the under ISRs of 1:1, the cumulative methane production volume of honeysuckle and midday tea dregs were 5832mL/100g and 5591mL/100g, respectively, after 192h digestion. Under the best inoculation ratio of 1:1, another mesophilic anaerobic experiment was carried out by mixing the residues of honeysuckle and midday tea as substrate at different ratios of 0:3, 1:2, 1:1, 2:1 and 3:0, respectively, which were to compare the methane production at 37±1°C. The result indicated that the ultimate maximum yield of methane was under mixed ratio of 1:2, the cumulative methane production volume of the mixed Chinese herbs residues was 9110 mL/100g after 192h digestion. Furthermore, the zero-order kinetic model was found to be suitable to characterize the removal ratio of substrate during 0~108h digestion while the biogas was generated fast, and the kinetic constant k was 50.49mL/h. To obtain the ultimate maximum rate of methane production, the anaerobic reaction should be controlled under the stage of zero-order reaction. Thus, the experimental results could provide scientific proof for anaerobic treatment and methane recycling in organic waste of Chinese herbs enterprises.

According to the coordinates of the particled graph, the paper presents a secondary pretreatment method which is invariant to translation, scaling and rotation. Having the advantages of efficient and accurate, the new method is significant to image processing. As the core of the pretreatment, orientation pretreatment is described in detail. In combination with the semi-structured data storage model, the new pretreatment method can help to achieve image content retrieval and data mining of a deeper level.

Multicast routing problem is a well know optimization problem for transmitting real-time multimedia applications in telecommunication networks. As the underpinning mathematical model, the constrained minimum Steiner tree problem in graphs is a well-known NP-complete problem. In this paper we investigate a new hybrid GRASP (Greedy Randomized Adaptive Search Procedure) approach where a pilot method is applied to further enhance the search for the Delay-Constrained Least-Cost (DCLC) multicast routing problem. Experimental results demonstrate the efficiency of the hybrid GRASP algorithm and the contributions of the post-processing pilot method to better solutions in most cases. The proposed GRASP approach is a competitive approach in solving the DCLC multicast routing problem.

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.

Monitoring the illegally occupied channels is very important for the management and regulations of reservoirs. This paper proposes an automatic and efficient approach to identify the changes in the river course with geographic information system and global position system using multi-temporal remote sensing images. Unlike the traditional river course monitoring system, this approach is mainly based on the change detection information extracting from multi-temporal high spatial resolution remote sensing images. Firstly, change detection from different information of multi-temporal remote sensing images are applied to obtain the change information thematic maps which can be used as working maps for on-site investigation are extracted. Secondly, GPS-RTK measurement technology is used to obtain 3-D position information of the terrain features points in those channel occupied areas. Then, an approach for calculating the volume of the channel occupied area is designed and developed by ArcGIS software using multi-temporal remote sensing images, 3-D position information and historical digital terrain date of channel occupied area. Finally, channel occupied area volume data and thematic maps are acquired by ArcGIS software. The data of reservoir is selected as experimental area, and the experiments have confirmed the high efficiency and accuracy of this approach proposed in this paper.

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 photovoltaic (PV) industry, as the renewable energy, has discarding the traditional energy consumption and dependence mode completely, which had attracted more and more attentions of the countries all over the world. This paper analyzes the polycrystalline silicon, as the most important step of the PV industrial chain, the effects of its development on China photovoltaic industry, and forecasts the output of domestic polycrystalline silicon industry by using the grey model. According to the forecast results, proposing the relevant suggestions for the further development of PV industry in China.

Low-carbon plays an important role in world’s developments. More and more countries adopt clean energy to reach their emission reduction objectives. This article analyses China’s national photo-thermal application—based on present situation of solar water heater industry’s development in China, using growth model in curve estimation to predict national annual production and possessing capacity. It also compares China’s and other countries’ policies in supporting solar water heater industry, and puts forward advises about improving China’s national solar water heater industry’s policies.

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.

Carbonate reservoir, widely distributed in china, is an important resource of oil and gas. Most of carbonate reservoir are very tight and need to be stimulated to increase the permeability for the flowing of oil/gas. Acid treatment is a kind of stimulation. However, the ordinary acid system cannot stimulate carbonate reservoir effectively because of the heterogeneity among formations. Based on a novel visco-elastic surfactant, this paper develops a self-diverting acid system (DCA) for carbonate formations. This system had been applied in the treatment of carbonate reservoirs successfully. Experiments studying the diverting mechanism had been conducted with HTHP Rheometer, parallel core flooding system and MRI Scanning system. The results indicate that: the viscosity of reacted acid can reach to 200 times higher than that of fresh acid. The injecting pressure of DCA is 20 times higher than that of ordinary acid (HCl) during the parallel core flooding experiment. MRI scanning images of the cores after acid flooding show that DCA can stimulate the cores with middle and low permeability more effectively. In middle and low permeability cores, the length of wormhole created by DCA is 4-8 times longer than that created by ordinary acid. At the same time, the relationship between flooding pressure and core permeability is also studied. This paper reveals the diverting mechanism of DCA through these experiments.

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.

Calcium oxide stabilized cubic zirconia powders were synthesized with electrochemical method using analytical reagent zirconium oxychloride and calcium oxide as the raw materials. From XRD analysis, zirconia powders doped calcium oxide are mainly being as cubic phase under the temperature lower than 1100°C. While the zirconia powders which did not doped calcium oxide were transformed from cubic phase to monoclinic phase when the powders were sintered at 750°C. The calcium oxide used as dopant in zirconia has two advantages, the first is that it can stabilize the cubic zircnnia, the second is that it can restrain the zirconia powders’ growing up.

Dimensionality reduction is useful for improving the performance of Bayesian networks. In this paper we suggest an effective method of modeling categorical and numerical variables of the mixed data with different Bayesian classifiers. Such an approach reduces output sensitivity to input changes by applying feature extraction and selection, and empirical studies on UCI benchmarking data show that our approach has clear advantages with respect to the classification accuracy.

A completely interconnected macroporous and microporous poly(l-lactic acid) (PLLA) scaffold was fabricated from a PLLA–dioxane–water ternary system by an advanced manufacturing technology called low-temperature deposition manufacturing. A proper fraction of water and PEG added into the polymer solution induces liquid-liquid phase separation and gelation. The liquid-liquid phase separation brings in a new micro morphology and gelation effect produces higher fabrication accuracy.

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.