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A design of 100 kHz-1350 W electric vehicle DC/DC converter using LLC resonant converter with integrated transformer is presented. The loss analysis based on theoretical derivation is performed to reveal the loss distribution. Integrated magnetic structure is adopted in the design to further increase the efficiency and power density. A 280 V-360 V input, 13.5 V/100 A output prototype is built to verify its advantage, and the efficiency at 320 V input, 13.5 V/100 A output is 91.5% at the switching frequency of 100 kHz.

This paper discusses master-slave communication among multi-S7-200 CPUs, its application on silk cake transport line, programming to realize data sharing, the motor linkage control, as well as automatic transport process of silk cake. The realization of automatic transport of silk cake reduced silk cake pollution during man-made transport, also reduced labor intensity of the workers. It is perfect integration of mechanical and electrical automation.

There are altogether three magnetic components in the resonant tank of LLC resonant converter: the series resonant inductor, the parallel inductor and the transformer. The method to realize the magnetic integrated transformer in LLC resonant converter is presented. The design process is provided, and a magnetic integrated transformer is constructed and the test results correspond well with the design values. A prototype of 1350 W, 100 kHz LLC resonant converter type electric vehicle DC/DC converter equipped with the magnetic integrated transformer is built to verify the performance of the magnetic integrated transformer, and the efficiency at 320 V input, 13.5 V/100 A output is 91.5% at the switching frequency of 100 kHz.

In this paper, we investigate the heat transfer of the power-law-fluids-based nanofluids in a rotating circular groove. The circular groove rotates with a constant speed and the temperature on the wall of the groove is different from the temperature inside in the initial time. The effects of thermophoresis and Brownian are considered. The thermal conductivity of the nanofluids is taken as a constant. We solve the model with the finite element method directly and discretize them using a continuous finite element scheme in space and a modified midpoint scheme in time. From the results we can find that the heat transfer enhancement of the nanofluids increases as the power law index of the base fluid decreases.

In a previous work researchers found that fluorinated acrylate (PHFDA)/styrene (PSt)/ sulfonated styrene (S) copolymer can enhance the viscosity of carbon dioxide (CO2) by factors greater than 100 at concentrations of 5 wt %. To further improve the efficiency of this copolymer, we apply the dissipative particle dynamics (DPD) method to investigate the link between copolymer molecular structure and the solution rheology. Results show that sulfonated copolymer molecules combine with each other and create self-assembly structures, which greatly thicken liquid CO2. We conclude that we should increase the sulfonation degree on the premise of a reasonable solubility. Using a further dissolving experiment, we finally fix the mole fraction of PHFDA, PSt and S on 60%, 24% and 16%, respectively. We test the viscosity of the improved copolymer with rheometer, results show that it can increase the solution viscosity 180-fold relative to neat CO2 at 334K and 28 MPa with a concentration of 2.5 wt %.

Niuxintuo reservoir is a low permeability fractured reservoir with high pour point oil reservoir.control agent formula obtained via laboratory test can effectively improve iulection profile, which can be evaluated by performance of salt tolerance, Core plugging experiments shows that this profile control agent has achieved a success rate of 97%,the purpose of blocking high permeability formation is achieved.

A facile approach is employed for the preparation of hierarchically porous structures monolithic ordered macroporous-mesoporous silica materials (OMS) using the commercially available and cheap polyurethane (PU) foam as monolithic template, triblock copolymer P123 (EO20PO70EO20) as structure-directing agent and tetraethyl orthosilicate (TEOS) as silica source, then monolithic ordered macro porous-mesoporous carbon materials (OMC) is synthesized by using monolithic ordered macroporous-mesoporous silica materials as hard template and ionic liquids as the carbon source. The silica and carbon monoliths possess uniform pore sizes (3.74-3.84 nm) and ordered mesostructure.

Software evolution process model (EPM) is a knowledge-intensive process which is described in EPDL(Software Evolution Process Description Language) and modelled by semi-formal approach based on EPMM(Software Evolution Process Meta-Model). In order to support process improvement and process automation, the execution model is represented by logic programming. Activity in EEM (EPM’s execution model) is not implemented until its needing all kinds of resources are satisfied by system execution environment. The paper discussed the representations of all kinds of resources in EEM and their structures are proposed. The preparation resources method is presented in order to execute the EEM automatically. The converter program is realized and the correct results have presented to prove the correctness of the method.

Software evolution process model (EPM) is a knowledge-intensive process which is described in EPDL(Software Evolution Process Description Language) and modelled by semi-formal approach based on EPMM(Software Evolution Process Meta-Model). EPM’s execution model (EEM) is represented by logic programming to create the knowledge base of EPM during constructing the EEM. Only its needing all kinds of resources are satisfied by system execution environment is activity in EEM implemented. The paper discussed the method and the algorithm of preparing resources is respectively presented in order to execute the EEM automatically. The converter program is realized and the correct results have presented to prove the correctness of the method.

The rapid prototyping technology was introduced, including its definition, principle and characteristics. The advantages of rapid prototyping technology in new product development were analyzed. Application of rapid prototyping technology in design of mechanical parts, industrial model, medical model, ceramic products, automobile model and products based on ergonomics was discussed. The feasibility of rapid prototyping technology in product design and the optimization direction was prospected.

The variations of secondary circuit parameters are limited by the parameters of primary circuit during PWR nuclear power station operation, the primary circuit average temperature should vary at the range of nuclear reactor operating safely. In the existing analysis of secondary circuit thermal efficiency at nuclear power station, the impact of primary circuit average temperature on the secondary circuit thermal efficiency is not taken into consideration. In this paper, the changes of primary circuit average temperature in actual operation are considered, the secondary circuit parameters are calculated according to the model of heat flux transfer between primary and secondary circuit, the thermal efficiency of ideal cycle is chosen as the evaluating indicator of secondary circuit thermal efficiency, the thermal efficiencies of ideal cycle in secondary circuit are calculated under the conditions of varying coolant average temperature with the method of matrix, and the calculated results are basis for the safe and economic operation of nuclear power station.

The mathematical models of the cold-water screw unit used on cold storage has been established.The operating condition of the unit which working at partial load has been simulated,with different return water temperature of condenser.The influence from the return water temperature of condenser on the cooling capacity and power consumption on the condition of different capacity of compressor has been analyzed, when the evaporation temperature is-10°C.The fact that the operational cost can be significantly reduced if the night cool storage technology is adopted.

It is difficult to sort fine non-magnetic particles only by the buoyancy of magnetic fluid. Therefore, based on the magneto hydrostatic separation, the centrifugal separation under the condition of centrifugal force would be an effective method to improve the efficiency. By establishing the mechanical model of centrifugal separation in magnetic fluid, this paper analyzes the kinematical equations of non-magnetic particles in three directionstangential direction, radial direction, and axial direction, and then theoretically explores the separation mechanism of this method.

With the improvement of peoples ideological awareness, people are becoming more and more attention to environmental protection and low carbon energy. According to the behavior of most people smoking in daily life, a portable multifunctional laser lighter is studied in this paper, which can effectively save the energy consumption and pollution of matches, fuel oil lighter. The laser lighter is mainly composed of two sets of sources. One source is the ignition source, which is the laser with power of 600mW and wavelength of 435nm. By design of optical system, the behaviors of lit cigarette, lit fireworks and ignite the paper are realized. The other source is the indicator source, which is the laser with the power of 20mW and wavelength of 650nm. We can realize the function of the tour guide indicating, projection screen indicating and a star pen by the design of zoom optical system. Using the software of solidworks, the mechanical design and safety design of the lighter is reasonable, and the overall size is 45mm × 25mm × 100mm. The device not only has the advantages of multifunction, portability and practicality, but also formed the basis for the further development of product.

The fisheye lens is widely used in the field of panoramic monitoring, this paper describes how to correct the distortion of fisheye image, and introduces a simple, fast, practical fisheye image correction method for fisheye image taken under specific angle. Also the detailed formulas are presented in this paper. Experiments show that the method can achieve satisfactory results.

When using the traditional SIFT algorithm extracts feature points, whose characteristics are rotation and scale scaling invariance, the problems are that the feature point extracted by the algorithm is too small and the shortages of real time and robustness. This article proposes a new method called Panoramic Image. This method can define the transformation parameters between the images by using the distances between cities to measure the similarity and using RANSAC with SPRT to diminish the mismatching. The consequence of the experiments demonstrates that this method can shorten the time of registration and prompt the matching feature points.

The ejective folds belt and the box like-trough-like folds belt in the area of boundary among Sichuan, Hubei and Hunan are separated by Qiyaoshan fault belt. Since early Middle Permian, the area has successively experienced the effects of paleo and morden pacific geodynamic system, resulting in multilevel and multi-phase structures. According to the geodynamic characteristics, the structural styles of study area are divided into compression style and rotation style, and subdivided into four first-order structure styles with analyzing their coal-controlling effects. Geodynamic characteristics, basement property and sliding layers are the main controlling factors of the structural deformation of coal-bearing stratum. The ejective fold is characteristized by narrow and steeper anticline with a vertical surface and broad syncline; coal-measures are developed mainly at the both wings of the anticline.

In order to solve the serial execution caused by multithreaded concurrent access to shared data and realize the dynamic load balance of tasks on shared memory symmetric multi-processor (multi-core) computing platform, new design methods are presented. By presenting multicore distributed locks, multicore shared data localization, multicore distributed queue, the new design methods can greatly decrease the number of accessing the shared data and realize the dynamic load balance of tasks. For illustration, design scheme of multicore task manager of server software are given by using new design methods. Results shows the new design methods reduce the number of access shared resources, partially resolve the serial execution of cooperative threads and realize the dynamic task balance of server software, which validate the superiority of this approach.

In recent years, algebraic semantics and its verification are increasingly important in software engineering. In this paper, firstly, the algebraic semantics of software evolution process description language (AS-EPDL) at activity level is explored. The algebraic semantics of activity level in EPDL provide an accurate framework for defining the semantics. In addition, the hierarchy-consistency and sufficient-completeness properties of the AS-EPDL at activity level are verified.

According to current technological situation that most of the existing Modbus networks are based on cable and the disadvantages of cable in bus architecture such as troubles during installation, much inconvenience in maintenance debugging and the potential safety hazard following high non-isolated, a design proposal based on Modbus digital transmission module is presented to realize the communication function without cable. During the design proposal, a wireless RF A7108 chip offered by SHENGKE electronic company is selected as the transmission carrier, which is followed by the transmit-receive pattern of Modbus protocol. And the transmission reliability of wireless data is guaranteed by the CRC check of every frame in the process of data transmission. This design can improve the problem of cable dependence in the traditional bus system and has a certain practical value within 500 meters radius in the industry with cable arrangement difficulty.

In 3D image processing, such as medical volume data and industrial CT volume data analysis, speckle noise suppressing significantly affects their accuracy. This paper utilizes a group of volume morphology arithmetic operators, mainly including volume open and volume close, by extending area morphology into 3-D space. Using these operators, the light and dark objects of small size could be removed directly from the 3-D space of the target objects, while the connectivity of the main 3-D target objects in the volume data is still preserved. To improve the volume morphology operations efficiency, we decompose volume data in bitplanes instead of in gray scale space to reduce the binary volumes. To verify the effect of the improved volume morphology operators, they are applied to suppress speckle noises in 3-D images of coral and rat skull and compared with original volume morphology operations. Experimental results show that the algorithm proposed in this paper can significantly reduce computing time, while maintaining comparable results to original operations results.

The result of the experiment using Labview real-time data acquisition and analysis, and considered the backward scattering Angle, detection range, chopper modulation frequency and test factors, thus draws the dust concentration and the relationship between the voltage detection. The results show that the modulation frequency up to 145 HZ, backward scattering Angle as close to ,the detection range as far as possible close to the flue, dust concentration and detection voltage can better meet the linear relationship for the future, it improves industrial smoke concentration on-line measurement provides a basis for the application.

A fiber Bragg grating (FBG) sensing network for vibration measurement is proposed and demonstrated in this paper. The light source of the described sensing technique is an erbium-doped fiber laser applying a 980-nm laser diode and a fiber Fabry-Perot tunable filter. The fiber laser has a 40nm tuning range, allowing many vibration sensors to be multiplexed on the same fiber. Reflected light wavelength shift of the FBG sensor caused by strain variation is converted to intensity deviation, which avoids a complex demodulation process. This sensing scheme can effectively increase the demodulation speed of sensing system up to 20 KHz. At least 20 FBGs can be multiplexed alone a fiber.

The thesis is aimed to study the characteristics nonlinear seismic response of the isolated continuous girder bridges with LRB. Inorder to achieve the aim, force- deformation properties of the LRB is considered as bilinear first, the bouc-wen model is adopted to imitate the force nonlinear deformation behavior of LRB, and by using Finite element method, the motion equation of the Isolation system of continuous girder bridge is established, then some shaking table tests towards the model of isolated continuous girder bridges with LRB is done. On this basis of it, by comparing the experimental results and calculation results, such as the acceleration and displacement of deck, vertical force of bearing, and the relationship between the Isolation layer displacement and the Level force displacement of the Bearing, we can see that the difference between the analytical results and the experimental results are very small. The results show that the calculation method can analyze Nonlinear Seismic Response of isolated continuous girder bridges with LRB efficiently. But when the vertical earthquake component is larger ,whether the results of the Vertical tension are produced or not, designing the Rubber bearings should be considered.

There is compelling evidence that TMEM16A fuctions as calcium-activated chloride channels (CaCCS), which was discovered by three independent labs in 2008 after Calcium-activated chloride channel current was first recorded in the 1980s. CaCCs are involved in many physiological processes, including transepithelial fluid secretion, smooth muscle contraction , sensory signal transduction and others. CaCCs are considers as potential drug therapy of hypertension, secretoy diarrheas, neuropathic pain, asthma, cystic fibrosis and certain tumors. In our previous study, TMEM16A with green fluorescence protein (GFP) fusion protein were subcloned into pcDNA3.1/Zeo. In this study, TMEM16A transient transfection conditon of Chinese hamster ovary (CHO) cells were optimized through liposome transfection and CHO cells expressing TMEM16A were got by stable transfection in which the classical calcium-activated chloride channels current was recorded by whole cell patch clamp technique. By a comparison between the results in this study and the results in previous study, both CHO and FRT cells are suitable for TMEM16A-pcDNA3.1 expression through liposome transfection and currents were recorded in both FRT and CHO cells by whole cell patch clamp technique, but our results indicated different purposes should require different cell lines and methods. These results were beneficial for the delving into study of TMEM16A-CaCCs by patch clamp technique which is the gold standard for real-time investigation of ion channels and their effectors.

Base on the 3R principles, the methods of the mine revegetation and landscape regeneration are found. They include the handling of abandoned mining facilities, the processing of the surface traces of the industrial production, the processing of pollutants, the transformation and reuse of abandoned mine pits, the plants landscape design, and the site characteristics of the landscape.

The discovery of ferromagnetism (FM) in wide band-gap semiconductors doped with transition metals (TM), known as diluted magnetic semiconductors (DMSs), has attracted much interest. These materials are applicable to spin-based optoelectronic devices working at room temperature (RT). Among DMSs, the system of Co-doped ZnO is considered as the most promising candidate, which was expected to robust magnetism. This paper focuses primarily on the recent progress in the experimental studies of ZnO:Co DMSs. The magnetic properties and possible mechanism of ZnO:Co DMSs prepared by different methods are summarized and reviewed.

Have proposed a heat recovery of fresh air ventilator system form,which is based on the technology of refrigerant natural circulation named heat-pipe. Describes the working principle of the unit, designs a new type of heat recovery air ventilator test equipment,and carries out a experimental study on its running performance.Have come to the effect of air flow and the temperature difference between indoor and outdoor for the heat recovery rate. Experimental results show that this equipment has a high heat recovery efficiency and a good effect on energy-saving . Through experimenting on the performance, laying a foundation for further optimization of unit design.

In order to obtain accurate dynamics parameters, a two-step method for robot dynamics parameters calibration is presented. In the first step a multidimensional matrix is constituted through transforming the configurations of robot manipulators and the product of quality and centroid coordinate about links is solved by using the least square method. In the second step decoupling dynamic equation of robot is deduced based on Newton-Euler algorithm, and through planning specific joint movement, the inertia tensor and centroid coordinate of robot links are calibrated making use of the pseudo inverse method. By the above two steps, the entire calibration of robot dynamic parameters is achieved. The correctness and feasibility of the presented calibration method is manifested by simulations and experiments.

The purpose and significance of bridge health monitoring is described in this paper. In order to study bridge health monitoring, Firstly, a finite element model for simply supported steel beam is set up on the basis of the Infinite Element Theory and the software ANSYS in response to laboratory experient. Through adding instantaneous excitation to the mid-span, do modal analysis for different injury of steel bridge model to reveal the natural frequency and mode shapes of the different injury of steel bridges, identify the different injury by comparing the index value and the rate of change.

A new groove design method of uniform strong strain of bar rolling was proposed based on the principle of strong plastic deformation to manufacture ultra-fine grain(UFG), and flat-oval groove type with the characteristics of big crushed and multidirectional deformation was set up. The numerical analysis model of hot continuous bar rolling process was created using nonlinear finite element method. The study of the law of plastic strain distribution after each rolling pass of the caliber series indicated that the caliber can satisfy with the precise size and shape, and can also better introduce the plastic strain to the center of cross section and get uniform strong strain. The largest strain was more than 5.0 in the center of cross section, in which condition ultra-fine grain can be fabricated. Therefore, this study provides important theoretical basis for the ultra-fine grain of bar rolling development.

The discovery of ferromagnetism (FM) in wide band-gap semiconductors doped with transition metals (TM), known as DMSs, has attracted much interest. Among DMSs, the system of Mn-doped ZnO is considered as the most promising candidates. This paper focuses primarily on the recent progress in the experimental studies of ZnO:Mn DMSs.

This paper studies a competition model between two species for two resources in the chemostat with the Beddington-DeAngelis functional response. The sufficient condition to the coexistence of positive steady state solutions is obtained by the mathematical methods of the fixed point degree theory in cones. Finally, Some results of numerical simulations is presented to prove and complement the previous mathematical results by numerical computation method. Furthermore, the research result implies that two species in the biological environment can be coexistence after a long time.

China will meet an increasing demand of the energy because of the growth of the economy, coal is being mined largely as the most important energy, but the mining brought in a series of construction of ecological environment problems. This paper established a comprehensive evaluation model for environmental impact of coal mining through three aspects of ecological stability, resource and environment carrying capacity, coal mining pressure with analytic hierarchy process (AHP). Based on this model, authors have evaluated the regional difference of ecological environment carrying capacity of coal mining areas in Shanxi province. The study results may be helpful to scientifically draw up the coal resources development strategy.

Qinhuangdao and national other places are the same, the construction energy conservation situation is stern, develops the construction to conserve energy imminently vigorously. Displays the area superiority, promotes the CL structure, to fundamentally does well the construction energy conservation work, to promote the Qinhuangdao urbanization advancement to be imperative. This article through the investigation and study to the Qinhuangdao CL structure Production enterprise, introduced that the energy conservation characteristic of the CL structure, founded the the question which existed in the promotion of the CL structure, searched after the countermeasure exploration speeds up the CL structure promotion work.

This paper describes the CL structural system and its evolutive history. By compared with other materials, the CL structural system has the following characteristics such as to reducing the weight of building, expanding area of the house, saving energy, extending the using life. The paper based on interrelated research, illustrated the application and effect of the CL structure in Qinhuangdao. In the paper, The author also explained the scope of the application of the CL structure and proposed to promote the application.

Ameliorating the smoothness of the data sequence is an effective way to enhance the prediction accuracy of GM (1,1) model. With deep analysis of the existing strengthen operator, two types of new strengthen operator have constructed in this paper according to the new buffer operator axioms and principles of information priority. The article has studied its characteristics and internal relations, such examples have demonstrated the effectiveness and practicality of operators, while solving the problem about the quantitative predictions inconsistent with qualitative conclusions we can refer to the methods.

The meshing generating spur bevel gear is presented by the method for precise modeling of gear in software Catia. Then by the excellent data exchange interface between Catia and ANSYS, the model can be transferred into ANSYS and bending stress of the gear tooth is calculated with finite element method ( FEM),which proposed design theory basis of generating spur bevel gear.

The high speed of image processing is required in the real-time image processing system. To improve the image processing speed, it is mainly implemented by hardware. This thesis constructs an image preprocessing system based on FPGA. Several typical image preprocessing algorithms, such as fast median filter, mean filter, Gaussian filter, Laplacian and Sobel operator edge filters, are implemented in the system. In the process of the system design, the characteristics and requirements of the image-processing implemented by hardware are fully considered. The parallel attribute insiding the image algorithm is effectively dug and the pipeline structure is adopt. All mentioned above are useful to optimize and improve the algorithms, reduce the hardware consumption and raise speed of image processing.

Voltage sag is one of the most frequent and serious dynamic problems that impact the power quality. To solve this problem, fast and precise detection of the voltage sag is needed. A detection method is presented in this paper, using single phase voltage information, to be applied in the typical condition of unsymmetrical three-phase voltage sag. This method adopts fast recognition of voltage disturbance and SPLL. Finally, MATLAB simulation has been used to verify the effectiveness of the method.

This article analyze the slope stability by strength reduction method named Phi-c which supplied by FE software PLAXIS. The reduction factor is suggest to be the safety factor of the slope at the moment when the slope reaches instability, the numerical non-convergence occurs simultaneously. The position of sliding surface and dynamic simulation of instability can be obtain as well. This article has compared the results calculated by other methods Bishop and ABAQUS with difference between 2%-3% which attest to its accuracy and practicability in engineering.

Dynamic voltage restorer (DVR) is used to mitigate the impact of the voltage sags. At first the structure of DVR and three basic compensation methods are introduced. Considering the compensation performance and the injection capability of the DVR, a generalized compensation strategy based on pre-fault compensation, energy-saving compensation and progressive phase rotation method is proposed. With this compensation strategy, the active power injected by DVR can be minimized on the premise of the quality of compensation. Simulation results demonstrate the efficacy of the proposed compensation strategy.

The residual Mg content ,spherodize ratio and nuclei of spherodial graphites(abbreviated SG) were studied by casting a series of similar composition ductile iron rods and white samples with different holding time of spheroidizing. The results indicate that the residual Mg content in the ductile iron was less and less as the holding time grows ,which causing the morphology of graphites transfer from spherodial to oval. Spherodize ratio change law is not continuous as increasing the residual Mg content which is divided at the 0.02%. The morphologies of nuclei of SGs core are typical examples of the highly magnified structure of spherical and irregular polygons; the diameters are about 0.5~2μm, consisting of (Mg, Ca)S along with CeO2and MgO. Disregistry δ between the nucleus compounds and graphite are low,which indicates that nucleus compounds are good nucleating site for SGs.The Mg element in nuclei of SG just act as nucleation substrates.it is the Mg which maybe simple substance in the metallic matrix that act as the role of spherodizer determines the graphite shape.

La1-xSrxMnO3(x=0.2, 0.04)/Si PN heterostructures were prepared by RF magnetron sputtering method, which have evident rectifying properties. Furthermore, the excellent rectifying properties are presented in a relatively wide temperature range for La0.8Sr0.2MnO3/Si heterostructures. The diffusion voltage decreases with increasing the temperatures, which is attributed to the modulation of the interfacial electronic structure of the heterostructures.

La0.8Sr0.2MnO3 (LSMO) films with SrMnO3 (SMO) diffusion barrier layers were deposited on (100) Si substrates at 600oC by RF magnetron sputtering. From X-ray diffraction patterns (XRD), (110) peak of LSMO has been greatly enhanced in LSMO/SMO/Si, which may result from small lattice mismatch between SMO and LSMO Rutherford backscattering spectrometry spectra (RBS) measurements clearly show that there is a sharp interface between SMO and Si and small diffusion between LSMO and SMO after introducing SMO diffusion barrier layer. Small lattice mismatch is also considered to play an important role in deciding good interface quality. The current-voltage measurement shows a good rectifying property of LSMO/SMO/Si when the thickness of SMO is 50 nm. On further increasing SMO thickness, the junction currents are depressed at the same applied positive voltage. We attribute the results to the bigger junction resistance caused through introducing thicker barrier layer.

This study presents a novel bidirectional dc-dc buck-boost converter compatible with the flywheel energy storage system (FESS) and a robust control for bidirectional power flow, according to the single cycle average current control scheme and proportional-integral (PI) control theory. The proposed converter and its control are designed to adjust voltage to achieve current limiting start up and final speed keeping of the motor in charge mode and maintain a constant output voltage in the case that terminal voltage of the motor in the FESS drops continually in discharge mode. Simulation results demonstrate high performance of the converter in both steady-state and dynamic operations.

In order to research on the disturbance characteristics of marine diesel engine with wing-assisted system, mathematical models of ship, diesel engine, propeller and wing were established. Disturbance characteristics of marine diesel engine which using the wing-assisted system was simulated by matlab/simulink software. The output torque and speed curves of the marine diesel engine at different conditions were obtained, by inputting different wing thrust fluctuation signal. The results can provide some reference value to the wing-assisted technology in the application of ocean transport ships, and which has a certain dominating significance for dynamic coupling of diesel-wing ship.

In order to research the effect of the blade wrap angle and outlet angle on the hydraulic performance of the low-specific speed sewage pump, the Reynolds time-averaged Navier-Stokes equations was discretized based on the finite volume method, and the modified k-ε turbulence model were chosen in FLUENT. Numerical simulation of the internal flow within the centrifugal pump with the specific speed of 60 at different blade wrap angle and outlet angle is carried out. The analysis of the velocity and the turbulent kinetic energy distribution in different cases, and predicts the external characteristics of the several cases based on the loss analysis method. The study results show that the efficiency of pumps increase with decreasing the outlet angle and increasing the wrapping angle at the design of sewage pumps. According to the analysis, changing the blade outlet Angle has much more influence on the performance of the pump than changing the wrap angle.

According to the loading characteristics of engine blades, a vibration bending fatigue system by using the ultrasonic fatigue test technique has been developed and the specimen is designed by finite element method, fatigue tests of TC17 between 106and 109cycles have been completed in this paper. The results show that the fatigue life of specimen increases over 107cycles and the initiation of fatigue cracks transfers from only in the surface of specimen to both in the surface and the sub-surface with loading decreasing.

To direct at heating system when it adopts quantity adjustment. Taking a community in Zhangjiakou as an example, using the method of Graphic theory to analysis and compare these two operation schemes: adjusting parallel pump's valve in shared pipeline and adjusting parallel pump's valve in non-shared pipeline. We can know that adjusting parallel pump's valve in non-shared pipeline is energy-saving, when the flow in pipe network is bigger than 79% of the boiler's total circulating water. There is a lowest limit of system's circulating water, when adopt the method that adjusting the parallel pump's valve in non-shared pipeline, otherwise it would damage the pump.