Search

Engine energy-saving technology is the key direction of passenger car energy-saving. This paper has built energy-saving potential model, which could forecast the potential of engine energy-saving technology in 2015 and 2020 under such two constraints: overall target requirement of fuel consumption and curb weight range. Afterwards, the model was used to calculate energy-saving potential of narrow sense passenger cars (including basic car + SUV + MPV), which were equipped with single turbo charging technology, single GDI technology and the above two kinds of technologies integration. The research results will provide decision-making support for enterprises’ technology selection and product development.

In order to understand the sedimentary characteristics of shale and prospects of shale gas exploration in the lower Silurian Longmaxi Formation northern of Guizhou Province, outcrop and core observations, thin sections, X-ray diffraction analysis and other means are used. Studies show that the thickness of Longmaxi formation shale is generally large, range from 20m to 200m, mainly develop in the water shelf. The mineral mainly compose of detrital quartz and clay minerals, and five lithofacies can be identified: black shale, silty shale, carbonaceous shale, calcareous shale and argillaceous siltstone. Longmaxi shale kerogen type is mainlyIand II, and Ro value is average of 1.87%, mainly in the mature - over mature stage. In addition, the TOC content and gas content of Longmaxi shale is high, what’s more, these two parameters have good positive correlation. Compared with the Barnett shale, both of them have some similarities in the development environment shale, shale thickness and type of organic matter and TOC content, while, Longmaxi shale is deeply buried and post-destruction more intense. Longmaxi shale sedimentary environment is stable, high shale thickness and stable distribution, good quality source rocks and high brittle mineral content, which has meet the basic parameters of shale gas exploration and development, and has a large shale gas exploration potential in study area.

The acquisition of the total organic carbon (TOC) content mainly relies on the geochemical analysis and logging data. Due to geochemical analysis is restricted by coring and experimental analysis, so it is difficult to get the continuous TOC data. Logging evaluation method for measuring TOC is very important for shale gas exploration. This paper presents a logging evaluation method that the shale is segmented according to sedimentary structures. Sedimentary structures were recognized by core, thin section and scanning electron microscope. Taking Wufeng-Longmaxi Formation, Silurian, Muai Syncline Belt, south of Sichuan Basin as research object, the shale is divided into three kinds: massive mudstone, unobvious laminated mudstone, and laminated mudstone. TOC within each mudstone are calculated using GR, resistivity and AC logging data, and an ideal result is achieved. This method is more efficient, faster and the vertical resolution is higher than △logR method.

The current card attendance check system in colleges has the problems of low efficiency and accuracy, and severe condition of taking attendance for others. To solve these problems, we have designed attendance check system for college students based on fingerprint identification technology. This system can share information with educational administration system, offering such functions as academic year and semester management, classroom management, lesson management, and schedule management, and attendance check authority management, etc. This system utilizes the characteristics of fingerprints, which carries uniqueness and stability and adopts the increasingly mature fingerprint identification technology. It can improve the quality and efficiency of attendance management for college students, and promote the information construction on campus.

For management the manhole cover effectively, the manhole covers intelligent monitoring terminal (MCIMT) based on dual frequency RFID and acceleration sensor was proposed in this paper. Through hardware designing, alarm algorithm designing, program debugging and packaging, we developed the MCIMT. The key performance testing and demonstration system operation shown the following results. Firstly, the MCIMT communication distance can achieve 800 meters under the open conditions and 300 meters under the occluded environment reliably. Secondly, the MCIMT embedded special state estimate algorithm can output the correct scene sate of manhole cover. Thirdly, the MCIMT could operation 3 years in manhole cover. Lastly, the demonstration system based on the MCIMT can alarm accurately and timely.

In order to analyze the mechanism of backfill and surrounding rock of open stope during subsequent backfill mining, take M1 ore body mining in a mine as engineering background, and simulate the mechanism of surrounding rock and backfill by using FLAC3D numerical software. Results show that the backfill can effectively alleviate or transfer the stress concentration state of the room floor and pillar, apparently restrain the displacement of the cavity plate and pillar, and improve the plasticity distribution range in a limited degree.

Since the features are not prominent and the algorithm is complex during whole reconstruction of section data, a step-by-step optimization reconstruction method is proposed. The order of reconstruction is optimized: line features are reconstructed firstly; Then arc features are reconstructed (constraints are satisfied between the arc and known lines); finally freeform features are reconstructed (constraints are satisfied between the B-spline and known lines/arcs). In this way, the reconstruction accuracy of the line/arc features is ensured in the first. Since freeform features have more freedom, it is convenient to be adjusted to meet the more constraints. Linear boundary constraints are constructed and the algorithm becomes optimization problem of the quadratic objective function under the linear constraints. The examples show that the reconstruction accuracy is improved greatly under satisfying constraints; the expected goal is achieved in real application.

Slicing of silicon, quartz crystal and other hard brittle materials mainly use dissociated abrasive multi-wire saw slicing technology, which exists some shortcomings, such as severe environmental pollution, lower cutting efficiency, etc. So it is bound to be replaced by fixed abrasive diamond wire saw in the future. At present, generally, the manufacturing technology of fixed diamond wire saw includes electroplating method and resin bonded method. Compared with electroplating diamond wire saw, the resin bonded diamond wire saw has obvious advantages, such as simpler production technique, lower cost, higher cutting efficiency, less environmental pollution, etc. In this paper, the polyurethane was chosen as matrix resin of resin bonded, and phenolic resin was chosen as curing agent, the preparation technology of thermosetting resin bonded diamond wire saw, is researched in this paper. Firstly, the effects of various compositions on resin bonded, are researched, then the optimal fomula and the manufacturing technology are determined

In this paper, firstly we utilize the elastic model, which provides the simplest representation of material behavior in civil engineering. This model is valid for homogeneous, isotropic, continuous materials that exhibit linear stress-strain behavior with no hysteresis on unloading. The elastic models include both isotropic and anisotropic elastic models. Then the Mohr-Coulomb model is used which can represent shear failure in soils and rocks in civil engineering and geotechnical engineering. After that, the strain- softening model is founded, which allows representation of nonlinear material softening and hardening behavior based on prescribed variations of the Mohr-Coulomb model properties (cohesion, friction, dilation, tensile strength) as functions of the deviatoric plastic strain. Finally, a case study is done for the stratified rock mass, the elastic modulus of the rock sample for different surrounding compressive are obtained, to exhibit the anisotropy characteristic of this type of rock material

A new research method that can estimate the demand of EV in China on the basis of vehicular emission inventory and carbon reduction restriction is put forward. By using MOBILE model and software, China vehicular emissions inventory is created. Then, the demand bill of EV is worked out, and replacement scale and proportion of EV are calculated too. In the conclusion part, quantitative data is given, offering theoretical support for the governments’ strategic policy-making in developing EV.

In this paper, two kinds of rubber surface modifying methods were studied. One was bis[3-(triethoxysilyl) propyl] tetrasulfide (Si-69) silicon alkane coupling agent and the other was crylic acid coupling agent. The mechanical properties of cement concrete with modified rubber crumb and with non-modified rubber crumb were tested respectively. The results show that as the rubber crumb addition rises, the toughness of concrete with non-modified rubber crumb increases while the compressive strength decreases, and both thoughness and compressive strength of cement concrete with modified rubber crumb increase. The chloride impermeability of the rubber concrete are much better than that of the Portland cement concrete. After surface modification the chloride impermeability can be improved more. The thermoanalysis proves that the surface of modified rubber crumb is grafted by polar function groups, so the surface changes from hydrophobic to hydrophilic. The scanning electron microscopy (SEM) analysis confirms that the interface between rubber crumb and cement matrix is improved.

Based on the technology characteristics of CNC system software, the corresponding assurance measures are set for the reliability in design stage, program implementation stage and software testing stage respectively. CNC system software reliability is improved by modularizing program design and structure program design, code review and program readability, using different reliability testing methods. Finally the purpose is accomplished that the whole reliability of CNC system software is improved.

A class of multi-variable decoupling control algorithm for aero-engines is mainly studied In this paper. Firstly, the mechanism of ADRC decoupling control algorithm is elaborated and discussed in detail. Secondly, an ADRC controller for some turbofan engine's nonlinear component-level model is designed to solve two-loop control problem according to the basic principle of ADRC. Compared with ALQR (Augmented Linear Quadratic Regulator) controller in full flight envelope, enough numerical verification tests about ADRC controller have carried out. Finally, simulation results show that the closed-loop system based on the ADRC decoupling controller has better disturbance rejection capability than the ones based on ALQR controller.

A function-oriented designing and generating technology for the point-contact tooth surfaces of spiral bevel and hypoid gears is introduced. The tooth surface parameters are determined directly with the designing variables of the instantaneous transmission function, the locus of tooth contact points and the tooth contact ellipse dimension to design the point-contact tooth surfaces with the expected performances. The formulae for designing are provided. The designed tooth surfaces are generated with the free-form bevel gear machine, and the basic equations and formulae for the four-axis generating of the tooth surfaces are presented. The generating motions are expressed as the functions of the work gear rotary angle, which is taken as a motion parameter. The methods to determine the motion functions and the other machine setting parameters are explained through an example.