Abstract:Focusing on a continuously variable transmission(CVT) hybrid electric vehicle with integrate starter generator(ISG), modeling and simulating of engine braking was conducted. An optical control strategy of regenerative braking was put forward. When there is no regenerative braking, engine brake force can be used effectively by changing the CVT ratio to reduce the braking force requirements for wheel brakes based on the calculated results of engine braking. When there is regenerative braking, the braking priority sequence is generator braking, engine braking, and finally frictional braking. A forward simulation model for regenerative braking system of hybrid electric vehicle was built. The simulation and analysis under typical driving cycles was conducted. The result shows the control strategy and the models are reasonable and feasible.

Abstract:By building a model of a typical exhaust muffler structure, a grid mesh was formed based on the calculation characteristic of the flow field. The software ANSYS CFX then was used to numerically simulate the flow and temperature fields in a muffler. The effects of the gas velocity and temperature variation on sound elimination performance, including the acoustics and aerodynamics performance, were analyzed. The result suggests that highvelocity turbulence and highspeed flow should be eliminated from muffler structures when designed. At the same time, to provide satisfactory noise elimination, pressure loss should be reduced as far as possible. The pressure loss can be decreased when reducing the perforation structure.

Abstract:By combining a driver model, a vehicle system dynamics model, and a vehicle lateral stability control system, the performance of the drivervehicleroad closedloop system through a pylon course slalom test was simulated. The simulation was done in accordance with the GB/T6323.1-94 standard. Vehicle stability control system effectiveness was evaluated by measuring the mean maximum yaw rate and the mean maximum steering wheel angle. The simulation results showed the slalom test value with lateral stability control was approximately 4% higher than without a stability control system. This indicates the controlling system improves vehicle handling stability.

Abstract:Based on an analysis of the current die design situation, the numerical simulation software Dynaform was applied to die development. In a compacting spring bracket project, the finite element method and shape forming technology were used to simulate and validate the pressing and forming processes. Toptobottom technology of Pro/Engineering next was adopted to design the die. The result shows such die design methods and technologies can help designers develop dies quickly and accurately and improve productivity.

Abstract:Quality, composition, and characteristics of fuel from 7 areas of P. R. China were analyzed. Fuel quality factors influencing engine emission performance were studied. Using fuel from the HuaZhong and XiNan areas, engine COx, HC, and NOx emissions were tested by adjusting the excess air coefficient and the advanced ignition angle. In light of the characteristics of aromatic hydrocarbon and alkenes of fuel from different areas in P. R. China, we have shown engines can operate smoothly and engine emissions can be decreased when the excess air coefficient and the advanced ignition angle are properly adjusted.

Abstract:Sensitivity analysis of motorcycle frames is useful for improving the design success rate. Based on sensitivity analysis theory and using the Monte Carlo and numerical simulation methods, a new 250type integral motorcycle model was built and dynamic sensitivity analysis conducted. Sensitive design parameters that have great influence on frame vibration were discovered. By modifying the values of sensitive design parameters, the vibration of some measuring points was reduced. This reduction shows that the sensitivity analysis method is reliable and practical, and it can be used in sensitivity analyses of other complicated structures.

Abstract:In order to assess the vibration performance of all terrain vehicles, a half vehicle model with 10 degrees of freedom was built. The model was solved using the time domain method. Road surface irregularity excites the model and was generated by a trigonometric function. Based on this model, the beaming of the frame was analyzed. The results show that the first beaming and second beaming influence the vibration significantly. As a result, a half vehicle model that includes the first two beamings of the frame can satisfy the vehicle vibration analysis precision requirements. Driver ride quality was evaluated according to ISO26311.

Abstract:Common gear pumps have numerous shortcomings, including poor flow quality, high unbalanced radial force, imbalanced “balanced compound gear pumps” with complex structure, many leakage points, high manufacturing and assembling precision, high cost, and difficulty using in industrial applications. This paper proposed a new design scheme of a parallel gear pump with three substructures. Based on the design model, theoretical analysis of structural principles, power density, radial force, flow characteristics, and flow fluctuating were carried out. The result shows the new pump design has the advantages of small axial size, high power density, the initiative gear balanced the gear radial force, and decreased the radial force of the driven gear. By selecting suitable numbers of teeth, it can reduce flow pulsation effectively and improve flow quality.

Abstract:A fuel system evaluation method was introduced to select the proper high pressure injection system for diesel engines. Using this method, the second generation common rail system of BOSCH Company was selected for use in the 4JB1 diesel engine. Based on this common rail system, a fuel supplying model was built using AMESim. The model included a high pressure pump submodule, a pressure control valve submodule, an injectors submodule, and a connecting pipes submodule. Through model simulation, the influences of parameters (e.g., rail volume, high pressure pipe length and diameter) on pressure fluctuations and pressure building were studied. Railpipe system parameters were selected based on simulation results. Experimental results show the railpipe parameters could satisfy the needs of rapid pressure response and low pressure fluctuations for common rail diesel engines.

Abstract:A new family of zerocurrent and zerovoltage switching (ZCZVS) pulse widthmodulation (PWM) converters was proposed, based on a new ZCZVS PWM switch cell. The main switches operate at ZCS on and off, the auxiliary switches operate at ZVS on and off, and the passive semiconductor devices in the ZCZVS converters operate at ZCS on and off. In addition to operating at constant frequency and reducing commutation losses, the new converters have no additional current stress or conduct loss in the main switch in comparison to hardswitching converters. The principle of the new ZCZVS PWM Boost converter was analyzed. The simulation results of the ZCZVS PWM converter are provided to verify the performance of the new ZCZVS PWM converters.

Abstract:One of the important technical problems of various implantable devices concerns effectively supplying sufficient energy to allow devices to work for extended periods, steadily and reliably. Presently, batteries and magnetic induction are only power supplies widely used in clinics. Because the capability of batteries is limited, implantable devices have shorter lives and low energy transfer efficiencies. We presented a means of transferring electrical energy into rechargeable batteries in implantable device by using volume conduction of biological organisms. An energy transfer model of volume conduction was created using ANSYS V10. We analyzed the energy transfer efficiency from simulation results and provide reference for further study of energy transfer of volume conduction.

Abstract:Addressing the problem of choosing a fault line under singlephase to ground of distribution network, we presented a new criterion based on analysis of the development of fault line selection and a method using wavelet packets. The feature frequency band, or the combined feature frequency bands of each line, in which the transient capacity current was concentrated was chosen for maximum energy. Based on the principle that the transient capacity current's energy of the fault line was larger than the that of normal lines, fault line selection can be carried out adaptively by contrasting the energy of the transient capacity currents of all lines in each chosen frequency band. The simulation results and spot testing data shows the proposed method can detect the fault line in distribution networks precisely and reliably.

Abstract:When an ignition system operates, conducted interference caused by transient voltage of the primary circuit will impact on the accumulator and the disturbance will travel throughout the vehicle via wiring. The ignition system can disrupt the Electronic Control Unit and the normal operation of other electrical devices. Spark plug gap noise simultaneously produces very strong radiation interference in a vehicle. We analyzed the changes of the ignition coil voltage and current when an ignition switch was turned on and off. A discharged circuit model of spark plug also was set up. The electric field distribution in an automobile was calculated. For these calculations, the highvoltage wire was considered to be a unipole antenna. This simulation indicates that using either damped wire or adding spark plug resistance can suppress spark noise effectively.

Abstract:Because electric parameters are crucial for indicating the operating condition of power generation equipment, an intelligent instrument for electric parameters measurement of power generation equipment was developed. A Hanning windowing interpolation algorithm based on FFT and a hardware frequency track were adopted to reduce the effect of leakage and fencing. In addition, a high speed AD conversion based on an external bus interface, a multiple feedback filter, an application of μC/GUI, and a multitask scheduler all were designed to improve timing and antijamming. Test results indicate the system is stable and easily operated. The measured relative error of electric parameter is less than 0.5%.

Abstract:An illuminance ratio model of both single and multiple sources was proposed. The model tried to compensate for a lighting dimming system acting incorrectly as a result of an illuminance sensor aimed at a workplace sheltered by paper or a human body. The method was based on a luminance transfer function matrix, and the model parameters were estimated via the least squares method. Simulated and experimental results show the illuminance calculated using the model is consistent with the actual situation. The illuminance sensor setting based on this model can not only reduce difficulties associated with laying lines, but also avoid incorrect action caused by the illuminance sensor aimed at a workplace sheltered by paper or a human body. This research serves as a reference for the design of lighting dimming systems.

Abstract:We studied experiments on phenol wastewater treated by hydrogen peroxide assisted with a cavitating water jet. Removal efficiency factors were studied, and the intermediate products analyzed by High performance liquid chromatography (HPLC) to reveal the degradation mechanism. The optimal cavitating condition was obtained via experimentation. Based on the results, the removal ratio of phenol reaches 99.85% under when the initial phenol concentration is 100 mg/L, the pH value is 3.0, the hydrogen peroxide concentration is 300 mg/L, the confining pressure is 0.5 MPa, and the jetting pressure is 20 MPa. The HPLC analysis shows that the ultimate products of oxidized phenol are maleic acid and acetic acid with the intermediate products of catechol, hydroquinone and pbenzoquinone.

Abstract:We conducted a nitrogen removal test using floating islands in polluted rivers. The results show the nitrogen removal efficiency of Cyperus alternifolius exceeds that of Vetiveria zizanioides which in turn is greater than flagleaf. The relationship among removal loading, coverage rate and inflow loading was studied. The boundary of coverage rate was 30%. There was a significant change in the relationship between removal loading and coverage rate. The relationship between removal loading and inflow loading follows a quadratic function. The appropriate coverage rate and inflow loading were found based on this test.

Abstract:Experimental study of recycling strontium chloride from strontium waste residues was conducted with ammonia chloride as the leaching solvent. The effects of the granule diameter of strontium waste residues, the extraction time, the mass ratio between liquid and solid and the n(NH4Cl)/n(Sr) on the conversation ratio was investigated using orthogonal and single factor experiments. The results show that the optimal strontium conversation condition includes strontium waste residues of 0.054 mm in size, a twohour extraction time, a 3.3 mass ratio between liquid and solid, and 3.8 n(NH4Cl)/n(Sr). Under these conditions, the highest strontium conversation ratio reached 96%. The kinetics of the conversion process is fractal.

Abstract:Perilous rock is a dominant geological hazard in Three Gorges Reservoir area of P. R. China. The Taibaiyan cliff at Wanzhou is a representative case of massive perilous rocks in the area. Using this cliff as an example, the conditions triggering massive perilous rocks were studied and described. This included examining the following three conditions: alternating layers of mudstone and sandstone; steep landforms such as cliffs or scarps; and intense rainfall. The massive development mechanism for perilous rocks was discussed, including microchained pattern gradual and interval evolution from the bottom to the summit of the cliffs individually as perilous rock, and a macrochained pattern evolving stage by stage from the cliff face backward up the mountain. In some respects, rock cells below sandstone in cliffs serves as the pulsating valve of the massive development mechanism for perilous rock. In any microchained pattern, perilous rock situated on summits is the easiest to rupture due to the fissure pressure. For any single perilous rock, two load compositions were derived. In addition, methods for analyzing perilous rock stability were established in detail using the limit equilibrium principle. Two key techniques, a union scheme that both supports and anchors and a union scheme that nails and anchors, are proposed in light of the massive development mechanism for perilous rock.

Abstract:An orphogonal frequency division multiplexing(OFDM) based cognitive radio architecture was designed to meet the transmission requirements of a cognitive radio system. After finishing the allocation of subtransmission, and keeping BER within the limit that ensures service quality, an adaptive bit allocation method was proposed to allocate the bit and energy of subtransmission dynamically. The total power for launching needed reached its minimum (or SNR per bit reached its maximum). Compared with the fixed bit allocation method, the proposed method is simpler, decreases the system transmission power, and has better BER performance.

Abstract:Software encryption cannot satisfy realtime requirements for multimedia applications which usually involve large volumes of data. To address this problem, an field programmable gate array(FPGA) implementation of the Cyclone EP1C6 for a Kolmogorov chaotic mapbased image encryption algorithm MASK was proposed. The algorithm was composed of four basic parts: Mixture, key Add, Sbox and Kolmogorov chaotic map transforms. These parts specifically act on the image as follows: diffusion, applying secret keys, nonlinearity, and permutation. The correlation of adjacent pixels, UACI and the key space of the system subsequently were studied. The source occupation proportion of the hardware was calculated statistically and showed low occupation. Among the advantages of the proposed system are high security, fast encryption speed, and low hardware resources consumption. The proposed system is suitable for implementation in inexpensive FPGA.

Abstract:A compact multicoupling microstrip bandpass filter based on microstrip stepped impedance resonator (SIR) characteristics was presented. The principle of second harmonic suppression with a proper impedance ratio was introduced, which improved the rejection at the stopband of the bandpass filter. A microstrip multicoupling SIR bandpass filter with 3.65 GHz center frequency and 3.5% fractional bandwidth was designed and fabricated. The result of simulating the filter showed -10 dB attenuation at the first harmonic center frequency, making the upper skirt deeper and the bandpass response more symmetric than filters without microstrip SIR. The experimental filter was measured and had -3.2 dB insert loss at the central frequency and a bandwidth of approximately 120 MHz. The measured result was consistent with the simulated one.

Abstract:An approach based on hybrid semantic model (HSM) was proposed to the solve problem raised in the retrieval process of product knowledge documentation. It expands the traditional user query to a semantic set composed of user preference, context and query, while representing the knowledge documents and user interest with an ontology based fuzzy concept. The leaves in the ontology are selected as components of the document concept vector with the weight determined by the depth of the concept in the ontology graph, the quantity of the information contained, and occurrence in the document and the whole repository. Furthermore, ontology is used to express context and query, and to construct a user preference model. Different relevancy computation methods are adopted for different retrieval models. The semantic similarity between query or user preference and documentation is computed by cosine method. The semantic similarity of context is estimated by the concept distance in the concept hierarchy. Finally, the method is shown by experimentation to be more effective than the classic vector space method.

Abstract:To obtain the most important influence factors in road route selection quickly and effectively, we put forward a method that we call an analytic hierarchy process. In this method, we first use a matrix to show the mutual relationships of factors. We then analyze and calculate the matrix. Finally, we obtain the relative importance of all factors in the overall system. The result derived using this method is more reasonable and more directviewing to reflect influence coefficient. And based on the firsthand information of designs and the social background, the method can give qualitative indicators before program design, which prevented blindness of designing process and the designer can get more suitable road lines.