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In order to make on-line monitoring on the temperature of high voltage switch circuit breakerand find outthermal fault in time. This paper puts forward a new method with radio frequency and magnetic saturation power supply technology to make on-line monitoring on the temperature of high voltage switch circuit breaker, it designs the high voltage switch circuit breaker contact temperature online monitoring device. The device mainly includes monolithic temperature collector and data receiver, they transmit data wirelessly, and this makes high temperature monitoring terminal and the data receiving terminal completely electrical isolated. Integrated temperature collector doesn’t need external power supply, it uses small CT saturation technology for continuous power. The experiment shows that the temperature error is ±2°C, it can meet online temperature monitoring requirements of high voltage switch circuit breaker contact.

With the development of economy, higher requirements for pipeline laying are raised. Among them, how to choose path for laying effectivelyand cheaply is the most important. Compared with ‘Dijkstra’, ‘Bellman-Ford’, ‘Floyd’ and ‘Dynamic planning model’, a new routing algorithm based on adjacent matrix is proposed and detailed processes and rules are designed. Additionally the effectiveness of the algorithm is proved through being applied to an example.

The mechanical and thermal response of elliptical head with multi-opening subjected to thermal loads, were carried out using ANSYS software. By dispersing the structure finite elements, the mechanical and fatigue behavior were discussed by APDL language following JB4732, and the result about stress evaluation and fatigue analysis are given, from the result, we can conclude that high first plus second stress and stress concentration may be formed at the intersection between center nozzle and elliptic, as well as between eccentric nozzle and elliptic. The structural discontinuity degree and temperature fluctuation has a big influence on stress concentration, as the most common, opening nozzle of a pressure vessel, the checking of dynamic and static of the structure, especially fatigue-checking are necessary.

Because of excellent mechanical, physical and chemical property Wf/Zr-based amorphous matrix composite attracts people’s interest and becomes the hot spot of science study and engineering application. In this paper, change regulation of hardness of target around crater by Wf/Zr-based amorphous matrix composite projectile and its mechanism are studied after firing test, and it is found that the section can be divided into 3 layers: the Martensite layer, the deformed fine grain layer and the normal matrix from the crater surface to the interior of the steel target and that the thickness of Martensite layer increases first and then decreases in the penetration direction when the velocity of projectile is 1200m/s.

A356 is a heat treatable cast alloy which has been widely applied in aviation and automobile industries. In this paper a Sb modified A356 alloy cast with permanent mold has been investigated in order to improve its mechanical properties by changing the needle morphology of the eutectic silicon. The results show that a small amount of Sb addition can contribute refined eutectic silicon morphology and enhance the mechanical properties, especially elongation of the A356 cast alloy poured in permanent molds. The optimal addition of Sb is 0.2 wt.%.

Freshwater stingrays employ enlarged undulating pectoral fins as their routine propulsion means. Their remarkable flexibility and maneuverability have provided many new inspirations for engineers. In this paper, a biomimetic stingray-like underwater robot was introduced. In order to investigate the mechanism of the undulatory propulsion, kinematic analysis and hydromechanics analysis were conducted. Lastly, underwater experiments were carried out to study the swimming performance of the robotic fish.

Based on the characteristics of current China's electricity power market, it is necessary to develop the self-regulation system for all market participants. This paper sets up index system based comprehensive risk evaluation for self-regulation construction, which covers market infrastructure stability, schedule fairness,trade compliance, electricity bill settlement risk. The evaluation criterion for each indicator is given afterwards. The key self-regulation information and subsequent trade behavior improvement measures can be attained after making the evaluation by calculating each index value, thus conducive to achieving the power market transaction stability and efficiency.

357-T6 is an alloy that has been widely used due to excellent casting properties and mechanical performances. The aluminum wheels can be cast with both permanent and low pressure die castings. In this study, the mechanical properties of 357-T6 were compared between the gravity permanent casting (GPC) and low pressure die casting (LPDC). The specimens were cast through permanent and LPDC processes, respectively and were heat treated under T6, with different aging temperatures 155°C, 165°C, 175°C and 185°C after the solution treatment of 545°C for 9 hours. The ultimate tensile strength and elongation were tested for both processes. The results show that both tensile and elongation of low pressure die casting specimens are higher remarkably than those in gravity permanent casting. The optimized aging parameter is heating at 175°C for 4.5 hours after solution treatment.

A new Al2O3particle reinforced Al matrix composite was fabricated through in-situ chemical reaction between Al and glass powder. The microstructures and element distributions of the composite were observed and analyzed through OM, SEM and EDS, respectively. The results show the reinforced Al2O3particle synthesized by in-situ chemical reaction are aggregated on the grain boundary. The grains can be refined with the increasing of powder. Eutectic silicone with granulous shape was found in the microstructure, which attributes to the modification of Na and Ca to eutectic silicone.

Investment casting is one of main precision casting processes to realize near net shape castings. For the castings with thin-walled cross section or complicated shape, it is easy to generate casting stress such as thermal stress, mechanical stress and phase transformation stress, resulting in casting deformation due to the uneven cooling and hindered contraction. Once three-dimensional deformation is formed, it is very hard to correct. In this paper the finite element method (FEM) was used to analyze the stress and deformation of thin-walled lost wax casting. The results show that the temperature and stress distributions are uneven in the casting and the tendency to deform is higher even with insulating shell mold. And based on the results, the technical measures of adding supporting ribs are adopted to restrain deformation. The practice of volume production indicates that no casting was rejected due to deformation defects.

In order to reduce the information chaos of product design, we present the main motions of Design-Element based product design that we call itDE-PD. Different from traditional product design process composed of function, style, or customer requirements etc.al,DE-PDis driven by the knowledge and information flows in product design iteration. InDE-PD, the product is composed of Design-Elements (DE) which is the integration of related knowledge and information. After discussing the definition and information construct ofDE, we present the iteration ofDEbased product design. To evaluate the method, a design case of beach motorcycle with limit mount ofDEsis conceived. Evaluation results show thatDE-PDis a promising approach for product design informatization.

The paper took a structure improvement of a coupling component for board-level photoelectric interconnection and analyzed its coupling efficiency by stimulation. Firstly, it briefly introduced the commonly used coupling components, analyzed the coupling performance, and selected a coupling component to improve its structure. Secondly, it introduced methods to improve coupling components, such as 45-degree gold-plated cross section, and manufacturing ball lens on both the top and the bottom to increase the coupling efficiency of coupling components. Finally, the optical simulation software Advanced Systems Analysis Program was applied to analyze the coupling efficiency. The coupling efficiency of improved coupling component was increased. The analyses and results are significant in engineering application and guiding.

The organic complex chelators (OCC) were synthesized and applied to stabilization of heavy metals in fly ash according to the municipal solid waste landfill pollution control standard. The influences of different chelators, amount of chelator, pH value of leaching, solidification time were investigated and optimized. Comparing to the traditional inorganic chelator, this OCC has more powerful performance of stabilization. Under the optimized conditions, the leaching concentrations for typical heavy metals Pb and Cd were less than 0.19 and 0.11 mg/L, respectively, which could meet the demand of landfill. The organic complex chelators could react with heavy metals to form stable complexes, which would be embedded in fly ash particles and have the strong ability to prohibit leaching from acidic environment.

As a cat well in Mahudang of Burma on anticline structure zone, YH-1 encountered narrow formation pressure window stratum in the process of drilling with the problem that loss of filtration is serious and the speed of air cutting rises rapidly. Application of drilling liner hanger into cementation, combined with expansive slurry system in well YH-1 has met cementing requirements. Well sections are qualified and sealing sections of high quality amount to 49.4 percent. The field application results display that the usage of drilling liner hanger in narrow formation pressure window well section, associated with appropriate slurry system are able to satisfy well cementation requirements.

Bamboo culms as a structural building material have many advantages, are the ideal material for the future green building, and are increasingly brought to the attention of the industry. If it is widely recognized and adopted by structure and architecture, the complete bamboo culms performance parameters, testing methods, application of standards, and digital design and manufacturing methods are needed. Bamboo culms as a new type of building support, axial compression performance is directly related to the safety of the bamboo-framed buildings. This paper aims to study the structural properties of the bamboo culms compression test methods, and compression failure was simulated. Simulation results and experimental results are consistent. The model proposed in the work provides technical support for the structure of bamboo.

For the study of highly precise simulation algorithm for the analysis of antenna, the basic thought of method of moment analysis of wire antennas is introduced. The mathematical model is established and the formula derivation is presented in this paper. The method of moment equation is solved through utilizing three different basis functions and weight functions. Two examples are given, and the computing results are contrasted with the simulation results of FEKO. The comparison result shows that method of moment is quite accurate when it is used to analyze wire antennas, and the computed results acquired by applying Galerkin matching method are the most accurate of all. In the end, an accurate and effective electromagnetic simulation method is presented.

The market for 1,3-propanediol (1,3-PDO) is growing rapidly due to its expanding uses in the polymer material industry. Catalytic hydrogenolysis of glycerol is a promising new way to produce 1,3-PDO sustainably. This paper reviews the recent advances in studies on heterogeneous catalysts for the selective hydrogenolysis of glycerol to 1,3-PDO. The main employed metal catalysts include platinum, copper, rhodium and iridium. With the intent to give a rationally guide to the development of new catalysts in future research, the catalysts performances are summarized and discussed with reaction mechanisms.

According to the defects of classical k-means clustering algorithm such as sensitive to the initial clustering center selection, the poor global search ability, falling into the local optimal solution. A differential evolution algorithm which was a kind of a heuristic global optimization algorithm based on population was introduced in this article, then put forward an improved differential evolution algorithm combined with kmeans clustering algorithm at the same time. The experiments showed that the method has solved initial centers optimization problem of k-means clustering algorithm well, had a better searching ability,and more effectively improved clustering quality and convergence speed. Keywordsdifferential evolution algorithm; K-means cluster algorithm;Cluster analysis

Preliminary studies on the hydrogenolysis of glycerol over the titania-supported Ru-based bimetallic catalysts (Ru-Fe/TiO2, Ru-Co/TiO2, Ru-Ni/TiO2and Ru-Cu/TiO2) were reported. The introduction of a second transition metal can obviously increase the selectivity to 1,2-propanediol of the Ru catalysts, but a deactivation effect was also found. The catalytic performances of the Ru-based bimetallic catalysts were discussed with a proposed reaction mechanism. The addition of Fe, Co, Ni or Cu enables the Ru-based catalysts to favor the dehydration route over the retro-aldolization route in the reaction process.

Non-Gaussian probability distribution radar clutter not only is temporal correlated between different pulses, but also is spatial correlated between different range bins. In this paper, the method of simulation and validation of radar clutter is proposed using spherically invariant random processes (SIRP). The amplitude probability function and temporal correlation function of radar clutter can be controlled respectively, and the spatial correlation function can be also specified. The computer simulation of K-distribution and CHI-distribution radar clutter is used to validate the method, and is to validate the amplitude probability function, temporal-spatial 2D correlation function.

With the deepening of the market economy, personnel flow, logistics, information flow, capital flow and other factors flow on the importance of economic development more and more intuitive, traffic more and more reflect the high-speed operation of the society, the traffic impact on the economic development to a certain extent, also reflects the economic development of a region. Economic development depends on the traffic is also growing. In almost every city in the country are faced with the same social hot spots, especially in the further development of the city, it is more and more obvious, to resolve this contradiction is not a department or a personal wish, but the urgent demand of the whole society in the process of constructing. Based on the basic situation of Nanchang city traffic as a model of the basic analysis, put forward the solution, can provide reference for government decision-making.

In an unmanned yard, some parameters of the system would change due to equipments wear and deformed. These changes resulted in the 3D reconstruction parameters changing. The inaccuracy of the 3D reconstruction parameters decreases the system operating efficiency and result in the waste of resources and energy. In this paper, a rapid laser parameter calibration algorithm was discussed, the experiment result in a real unmanned yard show this method is feasible.

A technology of ‘Time-going-backwards’ is used to search isomers of C36, molecular dynamic simulations of C36isomer evolution in He buffer gas at 2500K demonstrate that the isomers of low energy are important roles in the dynamics of C36and the lowest energy isomer—D2dare the most important role.

With the surge in the rapid development of the Internet and the number of Internet users, Jiangxi tourism e-commerce sites should continue to improve, and to seize the online customer base. In this paper to determine the site Jianzhan purpose, three aspects of of Jiangxi tourism e-commerce website design to offer some suggestions to determine the website target markets and rational planning of web content.

With the rapid development of computer science, image processing, and pattern recognition, people are paying more and more attention on research and application of machine vision, which has resulted in excellent results in many fields. Depending on the features of untouched, fast-speed, real-time, proper precision, anti-interference, the inspection technology based on machine vision has been researched deeply and comprehensive applied aboard. Recently, the size measurement technology based on machine vision has been applied in the size measurement of the machine processing parts. A case study of typical regular mechanical parts, algorithm of position and size measurement of line, circle center and radius are researched, and good results are got, which established an academic foundation for further measurement of complex parts.

The existing energy use for real-time monitoring, to the statistical data of system analysis, main factors determining energy consumption, through the computer, mobile phone, PDA and other port monitoring display. According to the specific energy consumption situation in the development of targeted energy-saving plan, adopt infrared intelligent switch, air conditioning control, efficient lighting, infrared remote sensing switches and other measures to achieve energy-saving emission reduction demonstration effect.

The X-ray diffraction method (iXRD) has been applied into the measurement of residual stress ultrasonic impact ultrasound before and after the impact test process residual stress of aluminum alloy welded joints. Research different inrush current, different impact time of different ultrasonic impact of the process on the residual stress of welded joints of aluminum alloy welded joints welding residual stress distribution and its variation. We can study the distributing status and disciplinarian, and testify the step to adjust the welding residual stress by ultrasonic impact treatment. The research supplys the data supports for welding residual stress engineering disposal and weld joint assistant consolidation to improve abilities against the gatigue. The research shows appropriate welding and ultrasonic impact treatment technics can effectively adjust welding residual stress and meet the RAMS demands about the product.

Withdrawn at authors request

This paper introduced a kind of bainite steel used for frog, and studied its repair welding processes. In this paper, four different welding processes were designed. Optical microscopy, scanning electron microscopy, vicker hardness tester, wear tester, impact tester, and high temperature abrasion tester were used to test microstructures, hardness, wear weight loss, impact absorbing energy and wear morphology. The conclusion was that when the current was 120A and the preheat temperature was 250°C the hardness of surfacing metal was the highest, the wear weight loss was least and the impact absorbing energy was the highest. In practical repairing works, this process could be considered.

The paper mainly focuses on the possibility of realizing the NMR spectroscopy in a non-static external field and discusses the experimental scheme for developing the probes with the abilities to provide a precise real-time map of the time dependent magnetic field. From theoretical side, the paper analyzes the effect on the spin transition by a time dependent longitudinal field. For a 1/2 spin system, we have derived a simple formula for the prediction of the probabilities of occupation of the 1/2 and -1/2 states in a non-static field.

The paper mainly focuses on the possibility of realizing the NMR spectroscopy in a non-static external field. The behaviour of magnetic moment under a time-dependent magnetic longitudinal field is much different from that one under a static magnetic longitudinal field, because the magnetic susceptibility is a more complicated complex when both of transverse magnetic field and longitudinal field are time dependent. In this paper, we calculate the magnetic susceptibility of the water and give an analysis of the effect on the magnetic susceptibility in a time dependent longitudinal field and RF frequency.

The six-phase permanent magnet synchronous motor (PMSM) is designed with two sets of Y-connected windings phase shifted by 30 electrical degrees. Two mathematic models of six-phase PMSM are established by different methods, which are based on dual d-q transformation and decoupling vector space respectively. By the dual d-q transformation, the electromagnetic torque is calculated based on the two sets of Y-connected windings separately. By the decoupling vector transformation, extra vector subspace is established, in which the current components have no effect on the electromagnetic torque. According to the different models, two vector control systems for six-phase PMSM are presented. The relationship and equivalence of the two control methods are indicated through comparison analysis and open-loop simulation. And the closed-loop simulation and experiment results show that the two methods have consistent control performance

In order to reveal the deformation and failure mechanism of coals, the evolution of coal’s inner structures should be discovered and studied. A serial of coal specimen collected from 600m deep underground mine were scanned by a μCT system before and after conventional triaxial compression testing respectively. All the CT images were enhanced by some digital image processing techniques and then collected together to reconstructed 3D models by self-developed software. The stress-strain curves of coals at different confining pressure were obtained, and correspondingly the evolution of the inner structure of coals were well presented by enhanced CT images. Experimental results indicate that the strength of coal agrees well to linear Mohr-Coulomb Criterion. CT images show that more cracks occurs with the increasing confining pressure. It was inferred that the damage become more severe with increasing confining pressure and cause the variation of failure from ductile style at low confining pressure to brittle style at high confining pressure.

Insufficience of osteogenesis and antimicrobial effect have been still impacted the long term clinical success rate of dental implants. A nanostructured titanium surface prepared by hydrothermal treatment with H2O2 was evaluated on its osteoblastic viability and antibacterial effect. Samples were divided into 2 groups: untreated pure titanium surface (Ti) and a nanostructured titanium surface (NT). The antibacterial activities against S.mutans and C.albicans were measured by film applicator coating assay, as well as the live/dead bacteria stain. The osteoblastic viability was investigated by SEM and MTT assay. Results showed that the active microbia on NT was reduced at 24h (P

The hydrogenolysis of biomass-derived glycerol was studied on Ru-Co bimetallic catalysts, including Ru-Co/TiO2, Ru-Co/ZrO2, Ru-Co/SiO2 and Ru-Co/γ-Al2O3. The addition of Co to the Ru-based catalysts can promote the selectivity to 1,2-propanediol (1,2-PDO). The support material and Ru/Co atomic ratio has a significant effect on the catalytic performance. Ru-Co/ZrO2 exhibited the best performance as regard to both the activity and the selectivity to 1,2-PDO. Co is a promising second metal component to adjust the catalytic properties of Ru-based catalysts for the selective hydrogenolysis of glycerol.

This paper mainly talks about the structure of new-energy autos batteries’ cooling fan. It gives the reasons for vibration in theory. It also improved the structure of damping pads for vibration absorption by comparing vibration absorption effect of damping pads made of two different kinds of material. In the end, the better-effect structure and material for vibration absorption is selected after the experimental comparison. In addition, the assembly technique is advanced for fan, which left a notable alleviation of vibration.

In order to measure the high-voltage transmission line voltage harmonic signal directly and timely, a new approach based on field intensity method is put forward, solving the problems of getting the high-voltage transmission line voltage harmonic signal indirectly by using the traditional methods. Through the establishment of the field intensity method to get voltage signal mathematical model so as to prove its correctness in theory, besides, the actual measurement circuit of harmonic detector is designed to verify the correctness of the theory. High-voltage transmission line harmonic detector can easily detect voltage harmonic content of the high-voltage line

The fly ash and coal gangue were used as main raw materials to roast solid insulating brick.Lower than solid clay brick (300 °C) which belongs to low temperature roasting , roasting time cycle is 24 h ,the ratio of fly ash and coal gangue is 60% :35%. the B7 admixing expanded pearlite compressive strength is 30.25 MPa . Strength reach general clay brick MU30 high-class level .Thermal coefficient of conduction is 0.4 W/(m.K), lower than general clay brick thermal coefficient of conduction 0.78 W/(m.K); In addition , B7 XRD pattern has evident quartz、mullite diffraction character peak and TGA-DTA pattern between 900°C~1200°C, following temperature rise, green body heat-absorbing , begin melt 、glass reduction .The result is high in strengths . SEM scanning show : after being roasted in 950°C , globular solid glass bead 、pearlitic drusy pearlite 、flocculation aluminosilicate phase and so on , raw materials particle interstices were filled with viscous hyaline, so that B7 turned out high strengths . Acidproof、alkaliproof、freezing test and strengths results show: the lasting quality of solid insulating brick was best.

Bridge construction is the national important foundation construction of bridge engineering, is the relationship between society and economy to coordinate development of lifeline engineering. Bridge construction of rapid development, huge capital investment, the economic society of the prominent role, making it to the bridge's safety, durability, more and more attention. Based on the analysis of detection results of existing bridges, bridge on the future work state of speculation, pointed out the possible development trend for the future to provide advice, bridge maintenance. As the bridge reinforcement and reconstruction to provide accurate and comprehensive data.

The hydrogenation of biomass-derived ethyl lactate was studied over several ruthenium catalysts. The effect of support (TiO2, SiO2, γ-Al2O3, NaY and active-carbon) on the catalytic performance was evaluated. The ruthenium catalysts were characterized by inductively coupled plasma (ICP), N2 physisorption, powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). The catalytic performance of the ruthenium catalysts is dependent on the intrinsic property of the support. Ru/SiO2 was found to be an efficient catalyst for the hydrogenation of ethyl lactate to 1,2-propanediol (1,2-PDO).

In order to research the influenced factors of sensitivity of ultrasonic nondestructive testing, the compared experiments using water immersion and contact method were carried out and the experimental results of sensitivities were obtained. The results showed that the limited sensitivities of probes with 1MHz and 2.25 MHz is very low. And the defects ofφ1mm, which distance not exceeding 1mm, can be detected by probes of 5 MHz and 10 MHz. The defects ofφ0.5mm can be detected by probes of 15 MHz and 20 MHz. The definition of defects apperance will be further improved for the probes with their frequency more than 15 MHz when the scanning step enough small. The distance of probes and defects has little effect on the detecting sensitivity.

Aimed at the self-excited vibration of caused by unreasonable clearance in wearing ring of the Francis turbine, whole flow passage of prototype hydraulic turbine which contains the clearance in wearing ring is numerically calculated by computational fluid dynamics software CFX based on N-S equation and RNG k-turbulence model. The result shows that the flow field in front of inlet of runner is unstable extremely, even if a tiny disturbance effects on, which will be out-of-balance symmetrically in the radial direction, then the force of runner will be unbalance, which will cause vibration of the hydraulic turbine. As well as, a reasonable clearance in wearing ring of the Francis turbine will reduce the impact of the water in the inlet of the clearance, and self-excited vibration of the hydraulic turbine will eliminate.

MIG welding and laser-MIG hybrid welding have been widely used to joint aluminum alloy in recent years. Residual stress and heat cycling of MIG welding and laser-MIG hybrid welding are analyzed by SYSWELD software. The results show that the peak values of the stress in hybrid welding is 30~50% less than the results in the MIG welded joints.

In order to detect the overheating fault of high-voltage switch contacts in time, and enhance the reliability of power supply system, this paper presents a new method for temperature rise monitoring, it is realized by WSN (wireless sensor network) and electromagnetic coupling which is a power-gaining technology. Based on the above method and technology, the author designs an on-line system to monitor the temperature rise of high-voltage switch contacts and builds a WSN based on ZigBee protocol. The system includes integral temperature collectors and data receiver, and the data between two of them is transmitted wirelessly by using the opening frequency band of 2.4 G provided by wireless module. The integral temperature collector does not need external power for its power is provided directly from high-voltage bus by the principle of electromagnetic coupling. The extensive system tests show the measurement error of temperature is ± 1.5°C, which can meet the temperature measurement requirements of high-voltage switch contacts.

Moisture transfer properties in fabric are critical to determine the thermal and sensorial comfort. Cotton fabric possesses many desirable characteristics that contribute to clothing comfort. However, in hot and wet environment or during some activities that human perspiration occurs, high absorbency of cotton makes its use undesirable. In this study, a chemical finishing method is developed to increase liquid moisture transfer properties on cotton fabric or clothing. The moisture management properties of the finished fabric or clothing were evaluated by using moisture management tester. Further wear trials were conducted to verify the comfort feeling toward finished area and unfinished area, which showed that this technique can effectively improve the overall comfort sensation especially during prolonged perspiration.