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This paper designs a new type of electro-magnetically actuated system, it uses alternating electromagnetic force to drive two permanent magnet sliders reciprocating movement, though the role of crank connecting rod mechanism output torque, moreover, the feasibility of electromagnetic power drive system and realizes the effectively control of the drive system are analyzed in this paper. Firstly, we use the construction model established by the ADAMS software to process dynamics and kinematics simulation analysis. Then, the data is used to design control system. Finally, the results show that the system is feasible and practical.

Tooling system for high-speed machining is one of the key components of high-end CNC machine , its stability and reliability directly affects the quality and performance of the machine. Based on the finite element method, developing a 3D finite model of high-speed machining tool system, studying on the stability of the high Speed machining tool from the natural frequency by the method of modal analysis. Analysis the amount of the overhang and clamping of the tooling , different shank taper interference fit and under different speed conditions, which affects the natural frequency of high-speed machining tool system. Proposed to the approach of improving system stability, which also provides a theoretical basis for the development of new high-speed machining tool system.

Expanded graphite is used as framework material in inorganic or organic heat storage materials commonly, of which the function is to improve thermal performance of the relevant materials. However, its negative effect is unclear. In this paper, the change of endothermic temperature of chemical heat storage material CaxZny(OH)2(x+y) by graphite addition is reported. Differential scanning calorimetry (DSC) is employed to perform the measurement. The result shows that the initial temperature and width of the endothermic peak decrease due to the action of the added graphite slightly; Along with the increase of graphite content, the endothermic peak moves to lower temperature further, the width and height of the peak reduce simultaneously.

The deformation and contact behavior between concrete face and rockfill are important to the safety of concrete face rockfill dams. Based on the monitoring data of Shanxi concrete face rockfill dam, the stress of concrete face, deformation of rockfill and facing joints were studied. It is shown that the rockfill deforms under the water pressure and weight, and the concrete face is compressed in central and otherwise around abutment during the reservoir filling. As the upstream concrete face deforms as the result of the rockfill deformation, the peripheral joints appear tensile, shear and settlement deformation. In addition, the main deformation of peripheral joints is settlement, which has a significant relationship with water level, especially for the upper ones.

Based on the database of Thomson Reuters, the bibliometric and patent information of China and US in the field of Building Energy Efficiency from 2006 to 2011 are searched. The R&D capacity of China and US in the field of Building Energy Efficiency are compared, the advantageous institutes in this field are identified. The cooperation trend between China and US on Building energy efficiency is analyzed. Some suggestions are proposed based on the data analysis.

Hα full-disk observation is an important observation of the sun. It has an important significance to the solar physics research. But its observation process may be affected by the system, resulting the observed images contain stripe noises. This paper describes a method to remove the particularity of stripe noises contained in the Hα full-disk solar image. This method includes the following four steps: First, decomposing the sun image into multiple detail scales by the multiscale transform; Second, doing special two-dimension signal conversion on the detail scales mainly containing the noises signal; Third, doing the adaptive Gaussian filtering on the two-dimension signal and restoring the processed signal to the image; Finaly, using the multiscale inverse transform to obtain the final restoration image. Experiments show that this method can effectively remove this type of noise interference from the solar image and improve the quality of the solar image.

The coupling characteristic of the tool-holder/spindle interface in high speed NC machine has significant influence on machine tool accuracy and process stability. With the example of HSK-E63, based on nonlinear finite element method (FEM), the coupling characteristic of the tool-holder/spindle interface under high rotational speed was investigated, the influence of interference, clamping force and rotational speed on the contact stress and the sectional area of clearance were discussed in detail. The results can be used as theoretical consideration to design and optimize the high speed tool-holder/spindle interface.

Harmonics always have a negative impact on control precision and grid quality. It has been found out that harmonic distribution is very germane to carrier frequency. Based on the analysis of conventional SVPWM, in this paper a chaotic carrier frequency SVPWM strategy is proposed, where the theory of chaos is applied to generate the desired random source for SVPWM carrier frequency. Simulation result proves that chaotic carrier frequency SVPWM can not only improve the waveform quality, reduce the low-order harmonics, and also flatten the high-order harmonics effectively.

As quality aggregate resources are exhausting with massive construction development, inferior aggregate resources somehow are the only picks on the jobsite. The negative impact of inferior aggregates on the workability of fresh concrete is becoming pronounced worrisome on the constructability of concrete structures due mainly to their poor gradation. Therefore, intelligent approach must be found to make fresh concrete workable and consistent while using inferior aggregates. In this study, uniform aggregate gradation curve, Aggregate Coarseness Factor (ACF) and Workability Factor (WF) were used to control the gradation of blended aggregates for achieving desirable workability of fresh concrete. Experimental study and engineering practices indicate that uniform aggregate gradation curve cooperating with ACF and WF are reliable tools to control workability of fresh concrete and obtain quality concrete while only poor aggregates available.

Since fully automatic image segmentation on natural images is usually hard to provide guaranteed results, interactive scheme with a few simple user inputs becomes a good alternative. This paper presents a novel interactive method based on regional attacking and merging mechanism within a cellular automaton (CA) framework. With an attacking rule based on regions maximal similarity, the adjacent homogeneous regions that are initialized by pre-segmentation are automatically merged and labeled, the users only need to indicate the object and background regions with rough markers. The whole process neednt set any similarity threshold in advance and the desired contours are effectively extracted by labeling all the non-marker regions as either background or object. Extensive experiments are performed and the results show that the proposed scheme can reliably extract the object contours from the complex background.

By using the 2000kN static and dynamic triaxial test instrument the mechanical properties of the low elastic modulus concrete is studied. The results of the experiment show that the failure modes of the unconfined compression test is crushing-type and the failure modes of the triaxial compression test is shearing-type. Utilizing the Mohr - Coulomb strength theory to design the low elastic modulus concrete cut-off wall is more in line with the actual engineering, but utilizing the first strength theory to design the dam cut-off wall is safer.

Galloping of overhead transmission line is a low-frequency, large amplitude, wind-induced vibrations of both single and bundle of overhead transmission lines, which have been one of the largest threaten for the security and stability of power grid operation. On account of the uncertainty and probability of galloping events happening, most of the study on transmission line galloping had still stayed on simulation or model test, only less of the study were in accordance with the accident records on-site. Several ten years study on conductor galloping had been proved that the laboratory built on real transmission line was the essential foundation and the effective condition for the systemic study on galloping. Comprehensive Test Centre based on Real Transmission Line (CTC for short) is the first laboratory focus on the study of conductor galloping and ice-accretion. whose content of tower type,conductor arrangement and transmission line length, currently have been the most abundant in worldwide. The establishment of the Comprehensive test centre have been very important on promoting the fundamental and systemic study in the relative field. Since the frequent conductor galloping under the condition of natural climate achieved successfully, CTC have developed several essential and valuable scientific projects. In this paper, CTC would be introduced from the aspects of basic facilities configuration, mainly function design and implementation, focal capabilities and some study outcomes at moment.

This paper presents a micro-grinding experiment on soda-lime glass to study the surface quality effective factors during micro grinding on hard brittle materials. The process of micro-grinding on soda-lime glass is showed in this paper and micro-grinding equipments are designed, fz(feed rate), ap (grinding depth), vg(Grinding speed) in micro-grinding brittle materials and their effects to surface quality have been discussed by experiments which were carried out on a desktop micro machine developed by NEU. Results proved that fz is the most important factor to the surface quality, and low surface roughness could be achieved by high vg and low fz in micro-grinding soda-lime glass.

A SiGe HBT power amplifier for Time Division Synchronous Code-Division Multiple-Access (TD-SCDMA) application with a single positive 3.3V supply has been demonstrated in this paper by adopting a newly proposed usage of the bonding wire. Though the emitter bonding wire may decrease the power gain, it can also decrease the effect of the knee voltage, thus increase the efficiency of the power amplifier. The post-simulation result shows that it can exhibit a linear gain of 29dB, output power of 30dBm, power-added efficiency of 38.49%, and -43dBc suppression at the second harmonic for TD-SCDMA application.

The paper deals with the temperature sensitivity of a new type strain sensor named carbon fiber smart layer (CFSL) made of epoxy-matrix composites with short carbon fiber mats. The experiment result indicated that the epoxy matrix CFSL is sensitive to temperature variation. It exhibits NTC effect in -5°C~25°C and exhibits PTC effect in 25°C~50°C. The NTC effect is relatively gentle and the PTC effect is relatively dramatic. The mechanism of both NTC effect and PTC effect is discussed based on the temperature sensitivities of carbon fiber itself and the fiber to fiber interface. Further experiment demonstrated its temperature sensing properties in the temperature scale in which the NTC effect or PTC effect exhibits individually.

Various reasons suggested to cause high performance concrete cracks were investigated, such as external and internal constraints, thermal deformation and creep. Firstly, the real temperature and stress fields simulated were suggested, and then the reasons for cracking and engineer measures for prevention from cracking in high performance concrete were analyzed. The main concept and characteristic of the measures are that the cracking prevention of concrete is a complicated comprehensive problem to be solved by application of combination with different measures in time under construction. The results show that the key economical measures for the prevention are the internal cooling water pipes and external superficial heat preservation. Moreover, the quasi real-time tracking observation, inversion, and feedback analysis under construction are also very necessarily, especially for projects using high performance concrete under severe conditions.

The observation series of concrete dam deformation is composed of the trend component, the periodic component and the stochastic component.In this paper, several stages are separated from the whole runtime according to the state of the dam.The trend component at each stage is extracted with the wavelet decomposition method, and modeled by the auto-regression method respectively. Then the characteristic polynomials of the auto-regression models are built. When solving these characteristic polynomials, the characteristic roots can be got. At last, to make a decision whether the dam is safe or not according to the trend of the minimum moduli of the roots. The application example shows that the conclusions of the method are consistent with the fact.

A MoS2/TiO2 nanocomposite was synthesized and characterized. Its lubricating properties and photocatalytic activity were also investigated, respectively. The as-prepared MoS2/TiO2 nanocomposite presented anti-friction properties better than those of the pure nanoMoS2. However, the difference in the anti-wear properties was not very notable between the pure nanoMoS2 and the MoS2/TiO2 nanocomposite. Moreover, the MoS2/TiO2 nanocomposite was also an excellent photocatalyst for the degradation of organic chemicals.

In order to improve the gauge factor of polymer-matrix carbon fiber reinforced composites (CFRP) for strain sensing, the carbon fiber sensitive interface was constructed in epoxy by effectively overlapping the CFRP laminates in local area. The strain sensitivities of the carbon fiber interface were proved by the cyclic tension test on the base specimens covered by the carbon fiber composites with the sensitive interface, and their much bigger gauge factors were revealed by the comparison with the polymer-matrix continuous carbon fiber composite. The sensitivity of the carbon fiber interface is originated from the change of the interfacial points due to the interfacial stress.

A remote power automatic meter reading system based on GPRS is introduced in this paper. The system using GPRS for communication and collecting the energy data in real-time, realize the optimization of the system resources. The components, structure, working process and the GPRS wireless transmission used in the remote power automatic meter reading meter are described and the practical application shows that the system obtained the desired results.

This paper analyzes deficiencies in the course teaching of computer network technology. Combined with the characteristics of computer network-related jobs. this paper builds a Work-process oriented, Work-task Derived “Computer network technology” course teaching model.

This paper describes the Ajax technology as well as asynchronous communication model and the traditional model’s difference, discusses the Ajax technology’s application in network teaching resources library system, implements asynchronous data transmission in the case of no page refreshing, enhances interactive of network teaching resources library system, and improves the efficiency of the network teaching resources server. At the same time, this paper also analyzes the adverse factors; this has certain guide significance for the use of Ajax technology to develop network teaching resources library.

This paper presents the design and implementation of a RF remote controller using code matching and frequency hopping technology. The proposed controller supports access to different random channels under disturbance environment. The work process of RF remote controller is composed of code matching, running state, handover state, and sleep state. Four system states can transform each other under corresponding external conditions. The suggested controller is more reliable than conventional ones especially during emergency condition such as noise and co-channel interference. The feasibility of the architecture has been demonstrated with a prototype implementation and presented in details.

This paper introduces a WSNs architecture design applied in remote monitoring of power towers. First, the system general design is presented. Second, design of nodes is given in detail including cluster-head, normal node and sink. Third, a fast change detection algorithm based on DC statistic is described, which can reduce the number of repeated image. Last, a clustering routing protocol C-LEACH with its application in power towers monitoring is discussed. The techniques described in this paper can provide scientific basis for state maintenance of power system equipment.