bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the Hamilton Dynamical System of Wheel-and-Rail Dynamical Model of High-Speed Train
Authors: Shen Hong Yun , Du Jian Hua , Wang Yu Lin
Published: January 2015

The study on dynamical model of wheel and rail of high-speed train has attracted many researchers nowadays. According to the damping force and the dry friction between wheel and rail, the dynamical model of wheel and rail of high-speed train is constructed and the Hamilton dynamical system of this model is analyzed to discuss its nonlinear dynamical behaviors, which will benefit the practical engineering of high-speed train.
Leaf Vein Extract Frame Based on Mathematical Morphology
Authors: Wang Li Jia , He Ai Ling , Guo Jing Xin , Li Hong Jun
Published: January 2015

In this paper, we present a leaf vein extracting algorithm frame which deals with contour and interior vein by employing different methods. The interior vein extraction method based on gray scale processing, mathematical morphology and processing in details is presented. We apply gray-scale morphology to process the image and extract the vein information. Through the analysis of the image information, processing in details is adopted to clear the information on the other tissues and insignificant veins. The extracted significant interior vein is overlaid with the leaf contour extracted through edge detection by pixel union operation. Experiment results show the effectiveness of the proposed method.
A Cascade Tracking Loop for Weak GPS Signals
Authors: Shi Ming Xing , Tang Bi Yu , Peng Ao
Published: January 2015

It’s important to get accurate carrier phase and frequency information when using a standalone GPS receiver. In weak signal applications, to keep a stable tracking is hard to achieve because measuring error will be huge when the SNR is low. Different methods are used to improve the SNR before the detector in a tracking process, such as coherence integration. And this paper keeps eyes on a different viewpoint, on how to refine estimation results. A cascade structure is introduced for weak signal tracking. This structure is divided into two levels. In the first level, raw phase estimation and accurate frequency estimation is provided to achieve stable work in low CNR environment. In the second level, the raw phase estimation is refined to achieve accurate tracking requirement. This cascade structure can also work jointly with any other SNR-improving technology to get a better performance.
Co-Evolutionary Algorithm between Helicopter and Submarine
Authors: Chen Ying Chun , Wang Xian Hua
Published: January 2015

A co-evolutionary algorithm is proposed for the play between a submarine and a helicopter equipped with dipping sonar. First, the theoretical foundation of co-evolution is elaborated. The movement model of helicopter and submarine, the detection model of dipping sonar under certain ocean environment are established. After defining the strategies of helicopter and submarine and fitness evaluation methods, the process of co-evolutionary algorithm is described. The optimal strategy of helicopter after helicopter evolution, and the optimal strategies of both helicopter and submarine after co-evolution are given
Cost Progress and Earned Value Analysis with Stochastic Activity Durations and Costs in Project Scheduling Problems
Authors: Zhang Jing Wen , Qiao Chuan Zhuo , Liu Geng Tao
Published: January 2015

This paper addressed two key issues: firstly, the cost incurred to complete an activity depends on its random duration; secondly, multiple methods to account for an activity cost are introduced. The upper and the lower bounds for cumulative cost curves over time can be tracked along a project progressed, which is obtained by mixing Monte Carl sampling with Gantt chart analysis. Moreover, these two bounds statistically represent the range for the budget cost of work scheduled; thus, the uncertain earned value analysis (EVA) is probed in our investigation. The conclusions indicate that project managers can obtain a degree of flexibility when adopting uncertain EVA to monitor status during project execution, which differs greatly from deterministic situations. Our study aims to illuminate some insights for the application of EVA under uncertain environments.
Investigating the Project Management Trends in IT Organizations in Saudi Arabia
Authors: Seddiq Yasser Mohammad , Alnuem Mohammed Abdullah
Published: January 2015

This is a study to investigate the current status and future trends of IT project management in Saudi Arabia. The organization ability of transition from traditional software development methodology to agile methodologies is addressed as well. The study is based on online survey that was answered by 17 respondents who represent six big organizations from the private and the government sectors. The results are analyzed and discussed. The expected obstacles that organizations could face when changing to agile methodologies are discussed.
Method and Application of Air Traffic Risk Quantitative Identification Based on Rough Sets
Authors: Yang Chang Qi , Wu Tao
Published: January 2015

The qualitative method, which can be divided into three types: the technocrat type, the chart type and the system type, is mainly adopted to identify the risk of ATC operation units but has the disadvantages in low work efficiency, poor visibility and easily influenced by subjective factors. In order to overcome its drawbacks, the quantitative risk identification model, which based on the idea of attribute reduction in rough set theory, is established to eliminate redundant risk indexes and improve the accuracy of risk identification on the condition of without losing key risk indexes. This mode will be applied to identify risk consisting in the control mode changing of ATC operation unit. The result show that 4 key risk indexes are extracted from 24 basic risk indexes which is premised on the consistency evaluation of expert evaluation results used the Kendall harmonious coefficient, and then provide the basis for the control decision.
Comparative Study on the Microstructure and Photoluminescence Properties of SnO2 Nano Particles Prepared by Different Methods
Authors: Allaedini Ghazaleh , Tasirin Siti Masrinda , Meor Talib Meor Zainal , Aminayi Payam , Puspasari Ifa
Published: January 2015

This study presents comparisons between the morphologies and photoluminescence properties of tin oxide (SnO2) nanoparticles prepared by two methods, namely the sol gel and the co-precipitation methods. The characteristics of the particles were analyzed using X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The particles prepared using the sol-gel method have a finer particle size and more spherical shape. However, no significant difference was observed in terms of morphology and homogeneity in the samples produced by either the co-precipitation or sol-gel methods. In contrast, the photoluminescence study shows that the emission peak for powder prepared using the sol-gel method was higher than that of the co-precipitation method.
Preparation and Properties of Graphene and its Nanocomposites
Authors: Ma Chen Chi M. , Hsiao Sheng Tsung , Liao Wei Hao , Li Shin Ming , Wang Yu Sheng , Lin Chi Wen
Published: January 2015

This study proposed a method to improve the mechanical properties and thermal conductivity of epoxy composites by incorporating multi-walled carbon nanotubes (MWCNTs) and multi-graphene platelets (MGPs) hybrid materials. The MWCNT can bridge adjacent MGPs and inhibit their aggregation effectively, leading to an increased contact surface area between MGP/MWCNT hybrid materials and epoxy matrix. From observing the fractured surface of composite by scanning electron microscope, MWCNT/MGP hybrid materials exhibited better compatibility than individual MWCNT and MGP did.The tensile strength of GD400-MWCNT/MGP/epoxy composites was 35.4% higher than that of epoxy, compared to only a 0.9% increase in tensile strength for MGP/epoxy composites. Thermal conductivity enhanced by 146.9% through incorporating MWCNT/MGP hybrid materials and 23.9% for MGP fillers, compared to non-derivatised epoxy.
Polymer Composite with Sisal Fiber Used for Node Reinforce in Space-Truss with Stamped Connection
Authors: Freitas Cleirton A.S. , Nobrega Mucio M.S. , Bezerra Édipo A. , Cavalcante Otávio R.O.
Published: January 2015

Space trusses are three-dimensional structures made of steel bars very frequently used at the roof construction. The bars, with tubular section, are linking in the 3D form by connections. There are several types of connections to attach these members. The most economical connection is the staking end-flattened connection, also called typical node. The reduced cost and the fast assemblage of the truss are among their advantages. However, such connections present disadvantages like eccentricities and stiffness weakening of the tubular members. This research presents suggestions of reinforcement and constructive correction in the connection in order to increase its capacity. The base for this is the reduction of the eccentricity in typical node applying the spacer. This spacer was made by polymer composite with sisal fiber. In this work was developed experimental lab tests in prototypes with fifty four meters square of area. The results show an increase of 26% for collapse in the truss load carrying capacity when the suggested changes proposed in this article are used for the staking end-flattened connections.
Experimental Study on the Implementation of Emission Standards Euro V Diesel Engine
Authors: Zhu Li Jian , Wang Yu Qun
Published: January 2015

To make diesel engine Exhaust meet Euro V standard , the most efficient way was to use SCR(Selective Catalytic Reduction).In this paper ,the composition of the urea-SCR system, essential parts and technology of urea-SCR and the strategy to reduce NOx exhaust was analyzed carefully. And through the test analysis, Selective catalytic reduction technical could Euro V diesel engine emission standard had confirmed.
A Stability Estimation Approach in Vehicle Planar Motion Considering Longitudinal Dynamics
Authors: Shi Wen , Yu Zhuo Ping
Published: January 2015

A stability estimation approach is proposed to support complementary stability criterion design in vehicle planar motion. The comprehensive effect of tangential force and axle load transfer on tire cornering characteristics is considered corresponding to the longitudinal dynamics effects. The effectiveness of different stability concept is discussed in terms of the physical meaning of state variables in 3DOF differential systems. Based on the sense of technical stability, the 3DOF model is simplified according to longitudinal dynamics characteristic within definite observation time interval. The central equilibrium points continuum properties of the simplified model can be used to estimate the vehicle behavior in planar motion.
The Research on Permanent Magnetic Synchronous Motor Vector Control Based on MRAS
Authors: Zhang Bo Ze , Ruan Yi
Published: January 2015

The precise speed and torque controls of Permanent Magnetic Synchronous Motor (PMSM) are usually realized by using speed or position sensor. However, the mounting of speed or position sensor requires an additional space. The cost of motor drive system with speed or position sensor is high, the reliability is low and is difficult to maintain. This paper presents one novel control strategy for PMSM sensorless vector control based on model reference adaption system(MRAS). This control strategy doesn’t need any speed or position sensor and can estimate the rotor speed with a few parameters. In this paper, PMSM itself is selected as reference model, and the mathematical model of PMSM which includes estimated parameter is regarded as adjustable model. The output error of these two models is used to drive the adaption mechanism and the estimated speed is obtained. The simulation results verify the proposed control strategy is effective, it has excellent dynamic and stable responses, the estimated speed precision is high and the system is robust.
Design and Realization of CAN-Based Main Control System of Multi-Station Meter Testing Equipment
Authors: Zhou Wei Wei , Huang Ji Ye , Gao Ming Yu , He Zhi Wei , Cai Bu Sen
Published: January 2015

In this paper, 0.05 grade three-phase main control system of multi-station meter testing equipment (MTE) is presented. This design is based on the S3C2440 core board as the control core, and the software is based on Windows CE(WINCE) embedded operating system. The device is displayed and controlled by 7-inch Touch Screen. The main control system communicate with the error instrument and PC through Controller Area Network (CAN) bus, and the largest number of error instruments can connect to CAN bus is 100. The main control system communicates through RS232 bus with three-phase signal source and standard electric energy meter, through RS485 bus with programmable power amplifier. In this device, calibration of energy meters can not only through the PC software, but also use the main control system. Compared to the traditional design of the electric energy meter calibration device, the design’s the man-machine interface is more optimized, the number of electric energy meters can be test in the same time is more, faster communication, stronger anti-interference ability, and calibration is more efficiency.
Experimental Analysis of Different Coolants Used in Plasma Cutting Operation for the Improved Electrode Life
Authors: Ranga Janardhana Ginka , Senthil Kumar Mani , Dhanasekar B.
Published: January 2015

The plasma cutting technology has been emerged as a developing technology which finds tremendous potential in fabrication and metal cutting industries. Thus for the cutting operation, the electrode inside the plasma torch plays a vital role for the plasma arc generation. The temperature of the arc is very high and at the electrode is around 3500°C. The cutting torch requires proper cooling system in order to prevent the electrode from quick wear due to the existence of high thermal gradient. The presented work aimed to study the impact of three coolants propylene glycol, ethylene glycol and de-ionized water flow over the electrode life. The experimental setups were arranged to study the heat transfer capabilities of the three coolants for different flow values and aimed to achieve the optimal flow rates for the efficient heat removal. The electrode life test trials were conducted to measure the electrode life for the flow values of three coolants in the temperature rise test. The optimal flow rates arrived from temperature rise test and the electrode life measured from life test are compared for the three coolant cases considered.
Large Maneuvering Trajectory Design and Dynamic Simulation of Inertial System
Authors: Zhang Yi Zhou , Li Si Hai , Du Yuan
Published: January 2015

As aviation technology continues to evolve, the function and safety of a large maneuvering have been required highly. As a large maneuvering system is becoming more and more complex , the trajectory design and simulation of a large maneuvering have become an important mean to ensure the mobile flight safety and design. The main focus of this research is to analyze the accuracy of the strapdown navigation algorithm and its impact in large motorized sport state by the large maneuvering trajectory design and its inertial system simulation. The authors build the model of the maneuvering trajectory by the Matlab program which is based on the design principle of the maneuvering flight path. Then, by using some coordinate system and the classical strapdown algorithm, specially attitude updating algorithm, the location update algorithm and the velocity update algorithm, the designed maneuvering trajectory model has been simulated and the simulation results are analyzed.
On the Exponential Stability of the Singular Distributed Parameter Systems
Authors: Ge Zhao Qiang
Published: January 2015

Exponential stability for the singular distributed parameter systems is discussed in the light of the theory of GE0-semigroup in Hilbert space. The necessary and sufficient conditions concerning the exponential stability are given.
Design of Virtex-7 FPGA-Based High-Speed Signal Processor Carrier Board
Authors: Ye Wen Hua , Li Huan
Published: January 2015

With the development of digital signal processing technology, the demand on the signal processor speed has become increasingly high. This paper describes the hardware design of carrier board in high-speed signal processing module, which using Xilinx's newest Virtex-7 FPGA family XC7VX485T chip, and applying high-speed signal processing interface FMC to transport and communicate high-speed data between carrier board and daughter card with high-speed ADC and DAC. This design provides a hardware implementation and algorithm verification platform for high-speed digital signal processing system.
An Optimized Design Strategy for the Hardware Implementation of the Hearing Aid Algorithms
Authors: Guo Feng , Yong Shan Shan , Guo Zhao Yang , Wang Xin An , Zhang Guo Xin
Published: January 2015

In this paper, a new design strategy for the hardware implementation of hearing aid algorithms is proposed. Two familiar hearing aid algorithms—Wide Dynamic Range Compression (WDRC) and Automatic Gain Control (AGC)—are implemented in one circuit as an example. By putting the common arithmetic procedures into common module, the operation units can be used repeatedly. In this way, the area and power consumption are visibly reduced.
Design of Smart Medicine Cabinet Based on STM32F107 and Network
Authors: Jiang Qiao , Xu Jun Ming
Published: January 2015

The paper designs a smart system cabinet based on STM32F107 and network, which can notify the aged to take medicine in time, and record the action of taking medicine all time, and send the results to server though the network module. The server will record the time of taking medicine, and according to the time to judge whether the aged take medicine in time. If not, the server will send text to family’s mobile phone through SMS Gateway, letting them to grasp the situation in time. It is more useful for the aged who always forget to take medicine.
Research and Design of Laser Displacement Measurement Based on the PSD
Authors: Duan Xin Wen , Sun Ye
Published: January 2015

This paper introduces a kind of measuring system based on two-dimensional position sensitive detector PSD and single-chip signal processing, and have discussed the key technology. Two-dimensional position sensitive detector (2 D-PSD) is a kind of testing device of light spot position information and the output signal is a kind of current signal related to the location information. PSD output signal processing circuits are usually made by the I/V conversion circuit ,the addition, the subtraction and division arithmetic circuit. System can quickly, accurately and easily realize the position measurement, with a simple implementation, low power consumption, fast response, etc, It can be applied to many remote laser center positioning measurement and general industrial control occasions.
Induction Motor Protection System Based on Fuzzy Logic
Authors: Qi Wei Min , Xiao Jie , Deng You Han
Published: January 2015

The protection is very important to detect abnormal motor running conditions such as over current, over voltage, overload, over temperature, and so on. When a failure is sensed by the protection system, a time delay should be specified to trip the motor. In the classical systems, motors are stopped with the time delay, which is adjusted constantly without considering the fault level. This paper presents a fuzzy logic-based protection system covering six different fault parameters for induction motors. The paper focuses on a new time-delay calculation for stopping induction motor and improves the overall detection performance. The time delay is computed by fuzzy logic method according to various fault parameters when one of the failures occurs on the motor. This system is successfully tested in real-time faults on the motor, and it shows that it provides sensitive protection by fuzzy rules.
Study on SEM and EDS Pattern of Charcoal Derived from Cogongrass by Pyrolysis in a Continuous Reactor
Authors: Promdee Kittiphop , Boonmee Chakkrich , Satitkune Somruedee , Vitidsant Tharapong
Published: January 2015

Charcoal derived from Cogongrass (Imperata cylindrica) consisting of cellulose, hemicellulose and lignin were collected for the experiment. The Cogongrass feeding to the continuous pyrolysis reactor at 500°C. When its passing the unit operate system, we can received all yield (liquid, solid and gas) on during pyrolysis, expecially, the solid product (charcoal). In this study, We have emphasized the characteristics and pattern surface and inside of charcoal by using Scanning Electron Microscope (SEM) and Energy Disperssive Scanning (EDS).
Design of Wideband Digital Array Beamformer Using the Variable Fractional Delay Allpass Filter
Authors: Wu Kai , Su Tao , Pang Jin Hao
Published: January 2015

To solve the space dispersion (SD) problem which makes the beam formed deviate from its expected direction in wideband digital array beamforming, a new wideband digital array beamformer (WDBF) is designed by introducing an identical variable fractional delay (VFD) filter on each sensor. The VFD filter is an all-pass filter with an infinite impulse response, thus it requires less filter order compared with finite impulse response filter. Since the VFD designed is suitable within the whole fractional delay range of-0.5 to 0.5 in sampling interval, the new beamformer designed is suitable for any direction without redesigning the fractional delay filter. In this way, the real-time property of the new beamformer is guaranteed. Simulation results show that the VFD deigned in this paper is high in precision. Applying it in the new WDBF, the SD problem is solved and the beam formed approximates the ideal beam very well.
Key Technologies for Optical OFDM in Optical Long-Haul System Using Direct-Detection
Authors: Tang Yi , Feng Ping Xing
Published: January 2015

A comprehensive theoretical model of direct detection (DD) optical orthogonal frequency division multiplexing (OOFDM) system is described in general. The principle of OOFDM is introduced in detail. Several key technologies in DD-OOFDM system have been discussed. The advantages and methods for optical single sideband (OSSB) and channel estimation are analyzed completely. Other key technologies are introduced briefly.
Design of a 2-Stage Broadband Low Noise Amplifier Based on the Agilent ADS
Authors: Chen Yan Fen , Zhang Fu Hong
Published: January 2015

The noise coefficient and the power gain of a low noise amplifier affect the whole performance of the receiver. This paper presents the design and simulation of 2-stage low noise amplifier using the MGA633P8 and TQP3M9028’s S parameters to set S2P files. Not only analyze how to insert elements to match a broadband circuit, but also make some optimization by using the Agilent ADS in the case of small signal. Simulation results show that the proposed work implements a high performance of 2-stage low noise amplifier which works at 824 MHZ to 1980 MHZ, the gain is greater than 25 db, the noise coefficient is less than 0.6, input and output standing wave ratio (SWR) are both less than 1.3.
The Design of Traffic Statistics System Based on Video
Authors: Zhu Li , Bai Lan
Published: January 2015

Passenger traffic volume is an indispensable data in the management and decision-making of large business, chain enterprises, cultural exhibitions, store sales, public safety and other public places. As an important means of market research, it can provide accurate and timely reference data for large institutions, enterprises operational decisions and integrated management. The system characteristics of industries, using a single camera for vertical shooting ways to monitor counting area. In this paper we studied the implementation method of some common traffic statistics system and key technologies involved, and design video-based traffic statistics system which has high performance and practical value.
Difference Schemes for Three Kinds of Nonlinear Flow Model in Low Permeability Porous Media
Authors: Liu Tang Wei , Lu Hong Zhi , Zou Xiang Ping
Published: January 2015

This paper discusses three kinds of typical one-dimensional nonlinear equations coming from low permeability reservoir seepage models with different boundary conditions. The several finite difference methods including forward difference method and second central order difference quotient method are used for the respective discrete process of three models. With these difference methods, the discrete schemes of models are obtained. Then the corresponding nonlinear discrete equations are deduced. While dealing with the boundary condition, the mid-rectangle formula is used. Finally, integrated discrete equations of three nonlinear equations are formed. The results should be meaningful for the numerical simulation of non-Darcy flow model of the low-permeability oil wells.
Measures to Control the Temperature of the Concrete Cracks in Foundation Mass
Authors: Mao Zi Chun , Wang Dong , Liu Yuan Bo
Published: January 2015

In the construction process, the concrete has been get fully utilized, there have been a variety of concrete strength grade configuration requirements and the corresponding raw materials. In the pouring process large volume concrete base, since the temperature stress generation will produce concrete temperature cracks, so the concrete pouring, raw material selection, after pouring temperature control measures have higher requirements. Based on a practical project, the construction of the control temperature stress did some exploratory research.
Research of Impetus Tendentiousness in Yuncheng Mine 3# Coal Seam
Authors: Wang Han Jun , Li Lie , He Tian Yu , Zhang Yan Qiu , Li Tao Tao , Hu Shao Yin
Published: January 2015

The depth of Yuncheng 3# coal seam is 600m, the country rock appear softening and weakening. Evaluate the impetus tendentiousness strength of the mine 3# coal seam through the 3# coal sampling on-site and laboratory indicators of the impact energy coal experimental study. The laboratory determination shows the impetus tendentiousness of Yuncheng Mine 3# coal seam belongs to class III which has strong impact tendentious based on national standards.
Effect of Dwell Time and Heating Rate on Thermal Residual Stresses in Co-Cured Aluminum/Composite Hybrid Shaft
Authors: Hao Wen Feng , Tang Can
Published: January 2015

In this work, thermal residual stresses and deformation of an aluminum/composite hybrid shaft was studied using ABAQUS FEM software. In order to reduce the thermal residual stresses and deformation produced during co-cure bonding stages due to the difference of coefficients of thermal expansions (CTE) of the composite and the aluminum tube, the curing temperature field was optimized. The effects of dwell time and heating rate were investigated. The results show that residual stresses can be reduced obviously by reasonable dwell time and slow heating rate. The dwell time and heating rate also effect the degree of cure which influenced the mechanic property of aluminum/composite hybrid structure directly.
Effects of Nano-Diamond Seeds on Mechanical Properties and Surface Morphology of Diamond-Like Carbon Films
Authors: Luo Yu , Chen Qing Yun , Yuan Huan , Xu Ming , Huang Shu Long
Published: January 2015

The effects of nano-diamond seeds on the performance of diamond-like carbon (DLC) films were investigated. In this study, the high uniform DLC films were deposited on substrates seeded with nano-diamond by using a magnetron sputtering system. Then, the effects of nano-diamond seeds on DLC films were determined. Raman spectroscopy revealed a decrease of sp3 fraction due to the introduction of nano-diamond seeds. Atomic force microscope (AFM) observed all samples have an average root mean square (RMS) roughness of 1.8 nm. Scanning electron microscopy (SEM) displayed that a large number of small size conical hillock geometrical anomalies can be caused by nano-diamond seeds. Indentation tests revealed that nano-diamond seeds can enhance the hardness of DLC films, whose hardness range is from 28.3 GPa to 32.1 GPa in this work.
Research on Corrosion Behavior of A3 Steel in Compound Sodium Molybadate Inhibitor Solution
Authors: Sun Cai Xia , Chen Yan Min , Cao De Yu , Zhang Min , Wu Jin Ying , Huang Chang Shan
Published: January 2015

The corrosion behavior of A3 in sodium molybdate inhibitor solution was tested by the static coupon method and the electrochemical workstation method. The results at diffident temperatures and in different concentration inhibitor show that the temperature had a important influence on A3 corrosion when the addition concentration below 500mg/L. The corrosion rate of A3 change less when temperature change from 20.5°C to 61.5°C.
Kinetic Study of the Adsorption of Dye onto Cotton in SDS-CTAB Reverse Micelles
Authors: Liu Zu Lan , Li Lan Qian , Liu Yi Ping , Lu Ming
Published: January 2015

Adsorption kinetic study of C.I. reactive blue 19 onto cotton was carried out in SDS-CTAB reverse micelles. The data of adsorption kinetics were examined using pseudo first-and second-order kinetic models. It was found that the adsorption kinetics of dye on cotton with diffusion controlling follows the pseudo first-order kinetic model.
Study on Mechanical Response Changes of Pavement to Aircraft Loads with Different Landing Gear Configurations
Authors: Zhang Wei , Dong Qian , Zhang Xian Min
Published: January 2015

The finite element model of runway is established based on elastic layered theory and it is used for analyzing the influence on mechanical responses due to changes of main landing gear configurations. The results show that the more the total number of wheels on a main landing gear is, the smaller displacement peak, maximum tensile stress under panel bottom and solid foundation influence depth are in conditions that aircraft loads are equal. When the landing gear spacing is smaller, the displacement curves in the loading area are gentler. The changes of configurations influence little on displacements in regions far away from loading area.
Selectively Catalyzed Oxidation of Benzyl Alcohol by FeIII–TAML/Hydrogen Peroxide
Authors: Li Ran , Wang Ge , Liu Yan Chun , Chen Xiao Bin , Sun Zhi Min , Liu Hui Ying , Wang Xiao Ning , Wu Zhen , Liu Zhen Dong
Published: January 2015

Benzyl alcohol was selectively oxidized to benzaldehyde with iron (III) complexed to tetra amido macrocyclic ligands (FeIII–TAML) as catalyst and 30% H2O2 as oxidant. The effect of reaction temperature, reaction time, solvent, amount of catalyst and oxidant on the reaction of catalyzed oxidation of benzyl alcohol were explored. The conversion and selectivity of this oxidation reaction were calculated from calibrated GC yields of benzyl alcohol and benzaldehyde. When oxidation reaction was conducted under the conditions: solvent NMMO: ethanol = 1: 1, n (H2O2): n (benzyl alcohol) = 2, n (catalyst): n (benzyl alcohol) = 1%, temperature 80 ̊C and reaction time 60 minutes, the conversion was 91.23% and the selectivity was 90.12%.
Use of Fleshings-Derived Collagen in Chrome Tanning Process
Authors: Puccini Monica , Castiello Domenico
Published: January 2015

The manufacturing process to transform hides into leather requires a series of chemical and mechanical operations. Fleshings represent one of the most important byproduct of the leather compartment. They are mainly constituted of raw collagen and through an alkaline hydrolysis a collagenous solution is obtained. In this work, an experimental activity research was performed for assessing the feasibility of the reuse of the collagen hydrolizate solution in the tanning phase. The hydrolizate has been used in combination with chromium salts to obtain bovine upper leather up to a dosage of 20% of solution (68% dry protein matter content) on the fleshed hide weight. Following a laboratory scale screening of the optimal operating conditions, crust leathers have been obtained on pilot scale. The final leather shows similar properties to those of the traditionally tanned leather in terms of technical and mechanical properties. Furthermore, a dry tannage is feasible, thus avoiding the production of effluents, and it is possible to adopt a retannage/dyeing/fatliquoring characterized by a lower consumption of chemicals in comparison with the standard procedure. The results obtained indicate the use of the collagen hydrolizate in the tanning phase as an interesting route for valorisation of fleshings.
Adsorption Performance of Pummelo Peel to Rhodamine B
Authors: Li Xiao Dong
Published: January 2015

The adsorption performance of pummelo peel to Rhodamine B (RhB) was tested to study the adsorption regulation and optimal adsorption condition of pummelo peel to dye waste water. The results showed that the RhB removal rate of 0.4 g pummelo peel to 100 mL 140 mg·L-1 RhB reached above 83 % under the condition of 30 °C, pH 8 and 60 min. The theroretical saturation adsorpion amount of pummelo peel was 133 mg·g-1 at 30 °C. The main adsorption pattern of pummelo peel to RhB was physical adsorption adsorption including external liquid film diffusion, surface adsorption and particle internal diffusion. The isothermal adsorption equation and secondary adsorption rate equation of Langmuir could be used to describe the adsorption process of pummelo peel to RhB.
Investigation of the Semisolid Rheological Characteristics of AZ91D Alloy
Authors: Zheng Xiao Ping , Li Hong Bin , Ji Ze Sheng
Published: January 2015

The semisolid shear rheological characteristic of AZ91D alloy were investigated. The results show that: during the shear rheological test at 570 °C, a critical shear stress and a maximum shear stress are happened. And with holding time increasing, the solid fraction decreasing and the solid particles distributing more uniformly, the rheological rate increases but the critical and maximum shear stress decrease. At last, based on rheological theory, a five-component rheological model of the semisolid AZ91D alloy is established, which is H1 - (N1 / H2) - (N2 / S).
Property Evaluation of Synthetic Aircraft Lubricating Oil of Corrosion Inhibiting
Authors: Liu Shuang Hong , Feng Bing , Wang Kun
Published: January 2015

Did property evaluation of engine test on shelf with the synthetic aircraft lubricating oil of corrosion inhibiting, detect the systematical parameters of engine, and the viscosity, acid number, flashing point, change of metal element of test oil. The results show that the new developed product has excellent antioxidation at high temperature, antiwear and lubricating performance, corrosion inhibition and anti-foam performance. And also has excellent long-term storage stability and service performance.
Study on Mechanical Properties of Self-Piercing Riveted Joints about Titanium Alloy
Authors: Lu Yi , He Xiao Cong , Wang Yi Feng
Published: January 2015

Adopting self-piercing riveting (SPR) joining, a new light sheet material joining method, to examine the joining of copper-titanium alloy (H62-TA1) sheet and titanium-aluminum alloy (TA1-Al5052) sheet. Also, using quasi-static mechanical test to figure out mechanical properties of H62-TA1 SPR single-lap joint and TA1-Al5052 SPR single-lap joint. In this study, using Dixon guidelines to eliminate abnormal value and adopting coefficient of variation method to validate reliability of test datum. The results show that failure mode of H62-TA1 joints is that the rivets are pulled out, failure mode of TA1-Al5052 joints is that the bottom sheet fracture. And tensile displacement and energy absorption of H62-TA1 joints are higher than that of TA1-Al5052 joints.
Quasi-Static Characteristics Analysis for Barge Bow Structure Based on Experimental and FEA Study
Authors: Mao Yi Feng , Liu Wei Qing , Fang Hai
Published: January 2015

In this paper, an experiment in a quasi-static conditions was carried out on barge bow model with its cross sections simplified. The characteristics of the bow structure were studied experimentally and Finite Element Analysis (FEA) was conducted to compare with experimental results. The experiment was performed by a compression and shear testing machine and the model was axially collapsed by a rigid board. The collapse mechanisms, load-displacement curve and mean crushing strength were investigated. The study showed that basic collapse mechanism of barge bow was clarified in participates with inner diaphragms. Moreover, the accuracy of FEA to estimate mean crushing force were validated by comparing with experimental results.
A Performance Study of Clinched Joints with Local Thermal Treatment
Authors: Wang Yi Feng , He Xiao Cong , Zeng Kai
Published: January 2015

In order to investigate the influence of local thermal treatment to microstructure and static mechanical behavior on clinched joints of cold rolling steel (SPCC) . The clinched joint performed local thermal treatment based on the test platform, and successively adopting metallographic, micro-hardness and static mechanics behavior test. The result show that the microstructure of SPCC clinching joints found a large amount of lath martensite after quenching treatment, and in comparison to which without local thermal treatment, its static strength is enhanced by 45.39% and its hardness increased by 77.78% .
Design and Flow Simulation on a Variable Structure Plasma Reaction Chamber
Authors: Liu Wei Feng , Yang Yi Yong , Ji Lin Hong , Cheng Jia
Published: January 2015

A new variable structure chamber was designed to plasma reaction with two-stage showerhead, and its flow filed dynamic control equation was analyzed and meshed by ICEM. The simulation research for the meshed models was analyzed by a commercial software-Fluent, by changing various parameters such as mass flow inlet, height, diameter and section of outlet. The result shows that the height and diameter variation for chamber has a little influence on the pressure upon susceptor. However, when the mass flow increases in inlet, the pressure improves, and it also changes as the section variation of outlet.
Heat Conduction in a Thin Film which Reflects Size and Memory Effects Induced by an Ultra-Fast Laser
Authors: Mao Yu Dong , Xu Ming Tian
Published: January 2015

An improved heat conduction model which reflects size and memory effects based on the CV model is proposed to simulate a one-dimensional thermal transport problem in a thin film induced by the ultra-fast laser. The results show that a thermal wave effect is appeared in heat conduction. We find that for the improved CV model in this work a larger Knudsen number will lead to a higher temperature. Although the improved CV model and the CV model lead to the similar thermal wave behavior, the thermal wave speeds for the two models are different.
Numerical Study on the Surface Convective Heat Transfer of Mass Concrete Structure
Authors: Li Biao , Tong Fu Guo , Liu Chang , Xi Nian Nian
Published: January 2015

The surface convective heat transfer of mass concrete is an important element of concrete structure temperature effect analysis. Based on coupled Thermal Fluid governing differential equation and finite element method, the paper calculated and analyzed the dependence of the concrete surface convective heat transfer on the air flow velocity and the concrete thermal conductivity coefficient. Results show that the surface convective heat transfer coefficient of concrete is a quadratic polynomial function of the air flow velocity, but influenced much less by the air flow velocity when temperature gradient is dominating in heat transfer. The concrete surface convective heat transfer coefficient increases linearly with the thermal conductivity of concrete increases.
Research on Stability of Overburden Structure around Longwall Mining Face in Steeply Dipping Seam Group
Authors: Ren Shi Guang , Wu Yong Ping , Yin Jian Hui
Published: January 2015

The steeply dipping seam group is defined by the two or more coal seams ,a pitch between 35°~55°. Using masonry beam theory, longitudinal bending theory and “R-S-F” dynamics control theory built a lower area overburden structure mode. Analysed the stability of low position coal seam. The balance requirement and the strength of the structure which is affected by the caving rock and lower coal roof were given. It easily generates two lower position steps rock structure in inclination along working face. Regular breaking of the second structure is the main reason leads to the imbalance of the structure between upper coal pillar and upper coal mining face.The interaction among multiple coal seam panels and overburden structures is the main reason that causes the rock disaster, the unbalance of the lower area may lead to pushing accident, the imbalance of the upper area can generate shock pressure.
Wind Tunnel Experiment on the Wind Effects of Low-Rise Buildings in Rural Areas
Authors: Wang Pu Qing , Li Yan Tao , Dou Yuan Ming , Zhang Jing Jing
Published: January 2015

At the present stage, no detailed specifications and codes about wind effects on low-rise buildings in rural areas were made in Chinese. In order to reduce casualties and property loss due to wind damage, the investigation of wind tunnel experiments were carried out. The results indicate that the influence of purlin and front and rear eaves on wind load should be considered in building design. Because a specific blowing angle of wind would produce the largest wind load in the surface of the house. In the structure design, the value of shape coefficient should be increased to a certain degree and also amplify according to windward and leeward roofs.
Analysis on Segment Floating in the Construction of Large-Diameter Crossing-River Shield Tunnel
Authors: Zhang Run Lai , Tang Li Ming , Tang Kun
Published: January 2015

Segment floating is a common problem met in the construction of large-diameter crossing-river shield tunnel. The factors affecting segment floating are discussed first and analyzed by numerical simulation, including the properties of grouting material, the speed of shield tunneling, grouting pressure difference, the tunnel longitudinal stiffness, frictional force between segment rings and weight of the supporting system. The simulation results indicate that segment floating will reduce by shortening slurry’s initial solidification time, slowing shielding speed, improving the tunnel longitudinal stiffness as well as increasing the frictional force between segment rings. And some measures are given such as applying new rapid-setting slurries, shear pins, rubber mats with high friction coefficient and pre-stressed bolts
Research on Determination Loose Zone of Surrounding Rock in Highway Tunnel
Authors: Huang Yue , Kou Jun Shu , Fang Hai Bo , Li Ming Liang , Liang Yan
Published: January 2015

With the vigorous development of China's highway construction, more and more stability problems of loose circle occurred in tunnel project, the deformation characteristics and distribution range of rock loose circle is very complex, which is of urgent need to further study. Based on geological data and construction program of Xi Shi slope tunnel, using the combined method of elastoplastic theoretical calculations and FLAC3D numerical simulation to analyze the distribution range of highway tunnel surrounding rock loose circle, and comparing it with the results of the measurements of surrounding rock deep displacement, thus, it is on the conclusion that grade IV rock loose circle of Xi Shi slope tunnel is in the range between 2.0 to 3.0m. Verifing the reliability of the method, and providing a strong guarantee for the design of support parameters.
Study on Spatial Nonlinear Vibration Characteristics of Cables with a Particular Constraint
Authors: Liu Jian Mei , You Bin Di
Published: January 2015

In order to study the nonlinear vibration problems of cable with a particular constraint, the mathematical model for the object of study should be established firstly with the elastic mechanics method. In order to obtain the mathematical model of differential form, the Galerkin method is used to make the mathematical model discrete and modal truncation, so the infinite dimensional solution space of the mathematical model can be transformed into the finite dimensional one. Main factors influencing the vibration of the cable system are analyzed, and the simulation analysis about the effects of various parameters on frequency is carried out. The analysis results show that the internal resonance modes may exist, and provide a theoretical basis for improving the safety and reliability of laying cables in actual conditions.
Strong Motion Observation from Recent Destructive Earthquakes in China Mainland
Authors: Lu Da Wei , Yang Zhi Bo
Published: January 2015

Strong earthquake motion observations have gathered much useful data for the seismic-resistant design of civil engineering structures, and for developing earthquake prevention technology. The performance of Chinese strong motion network has been evaluated from recent earthquakes in Chinese Mainland. To follow the new requirement of the earthquake mitigation plan, some new practice of strong motion observations are described, including rapid urban ShakeMap, earthquake early warning system.
Unmanned Aerial Vehicle Maritime Cruise Base Site Selection Strategy Research in the Bohai Sea
Authors: Wei Lei , Li Yun Bin , Xu Jun Hui , Luo Xiao Xia
Published: January 2015

Since the maritime traffic accidents and oil spill risk problem is getting increasingly serious, on the base of the maritime and oil spill accidents historical data analysis, the risk source in the Bohai Sea is discretized into finite cell. The risk analysis in matter element analysis method has been used to determine every cell’s level of risk and the demand for cruising power of each risk point has been evaluated. The specific location to build maritime unmanned aerial vehicle (UAV) cruise base needs to go through a cost-effectiveness analysis. Taking the relationship between risk point and cruise base’s location into consideration, the multi-target site selection model of UAV cruise base has been established. In this model, genetic algorithm has been used to optimize the site selection and finally, it is able to provide decision-making suggestions for the planning and construction of the Bohai maritime UAV cruise base.
Features of Quality Control of Free of Cement Binder of Non-Hydration Type
Authors: Voitovich Elena Valerievna , Kozhukhova Natalia Ivanovna , Cherevatova Alla Vasilievna , Zhernovsky Igor Vladimirovich , Osadchaya Maya Sergeevna
Published: January 2015

Analysis of methods of quality control, applied for binding systems and based materials was curried out. Also the classification of quality control methods for nanostructured binder (NB) in the light of its adaptability to this binder and composites on its basis is developed.The scheme of quality parameter control for NB and based materials in the framework of technological process "raw→binder→final composite" is developed. The basic characteristics of NB on the basis of quartz sands of different deposits are studied as well as the norms and requirements to controlled parameters when production process, allowing supplying quality of final product are determined.