bluuebunny/crossref_metadata_2025 huggingface dataset:
Large-Scale Virtual Simulation of the Solar System Based on Java3D
Authors: Chen Xiao Liang , Chen Jian Xun , Liu Hao
Published: December 2014

As the modeling of the solar system is difficult and inaccurate, the 3D modeling of the planets in the solar system is studied by using Java3D technology. To make the revolution of simulated planets meet Kepler's laws while traveling around the sun, an improved approximate algorithm to calculate the optimum angle and the vertex coordinates of each planet is proposed. Using java3D perspective projection technique, the observation coordinate system is determined, and real-time viewpoint setting as well as roaming processing is realized. Through multiple view technique, we can observe the movement of celestial bodies from multiple aspects to obtain vivid simulation effects of planets' behavior in the solar system. Simulation results show that the virtual simulation platform developed based on java3D can improve the accuracy and naturalness of solar system simulation.
Modeling and Simulation Research of Lidar Tomography Imaging
Authors: Qu Fu Qi , Shu Chang , Tu Jian Hua
Published: December 2014

Lidar tomography imaging has been shown a technology to obtain high resolution image of remote object, and has great application value in the field of space object surveillance and identification. In this paper, the fundamental of Lidar tomography imaging is given, a modeling method of Lidar tomography imaging based on chirped pulse is presented, in which, projection data of different observation angle is achieved by extracting the envelope of chirped pulse echo after its coherent receiving and compression processing. The results of simulation indicate that the outline image of the target can be obtained when the range of projection angle is larger than 60 degree. Imaging experiment validates the feasibility and effectiveness of the presented method.
Researching on Characteristics of Rayleigh Waves
Authors: Zhu Xu Fang , Yan Bing
Published: December 2014

Rayleigh wave is a secondary wave characterized by low frequency and strong energy, propagating mainly along the interface of medium and rapid attenuation of energy with increase in interface distance. The same as reflected wave and refracted wave, Rayleigh wave also contain subsurface geological information. In this paper, the concept of the Rayleigh wave, wave equation, dispersion equation, the frequency bulk characteristics and the application of the actual data are used to indicate the characteristics of Rayleigh wave and its application.
Research on Magnetometer Positioning Technology Based on a Variable Magnetic Source
Authors: Zhang Shu , Liu Da Ming , Zhang Hua , Zhou Si Ning
Published: December 2014

The precision of magnetometer positioning is affected by the geomagnetic anomaly, and traditional positioning technology cannot be applied to the motion sensor positioning. A magnetometer localization method based on a variable magnetic source is proposed. The method localizes a magnetic sensor by the absolute value of the magnetic field. Positioning process does not use geomagnetic coordinates to avoid the effects of geomagnetic anomalies. The method uses time-division multiplexing technology to achieve the motion sensor positioning. Simulation results show that the average positioning error is 0.3% and the maximum positioning error is 1.3% when the tilt angle of the magnetic source is ±1 degree. It has the advantages of high precision.
A Precision Resistance Generator for the Calibration of RTD-Based Temperature Instruments
Authors: Chen Pan Hui , Guo Li Feng , Lu Gu Bing , Jin Chuan Xi
Published: December 2014

A new calibration method for RTD-based temperature instrument is introduced. The precision resistance is generated using digital-controlled relays to switch a precision resistance network which is similar to the resistance box. We also present a new switch algorithm to reduce the influence of initial error of the precision resistors. The resistance of the precision resistance generator varies from 80.00ohms to 260.00ohms with a 4-wire output interface. It is convenient that using this precision resistance generator to test the nonlinear of temperature transmitters based on Pt100. Our test shows that the generator can provide a precision resistance with an uncertainty of less than ±0.02ohms.
Research on Identification of Induction Motor Parameters Based on Nameplate Data
Authors: Wang Xing Wu , Zhang Zhao Yan , Lin Yong Jun
Published: December 2014

A new method for identification of motor equivalent circuit parameters is proposed based on motor nameplate and particle swarm optimization (PSO). That is effective solution to the present problems of motor equivalent circuit parameters identification method. An accurate motor equivalent circuit is built by introducing an equivalent stray-loss resistance, mechanical loss, and slip loss of ring brushes contact for wound motor. The identification accuracy of motor equivalent circuit parameters is improved. An identification optimization model of equivalent circuit is established based on motor nameplate parameters and motor equivalent circuit’s calculating parameters. With PSO for solving optimization model is achieved a higher probability optimization goals. Finally, a group of equivalent circuit parameters to achieve the objective function value is randomly selected. The motor electrical parameters is calculated at different speeds with the equivalent circuit identified parameters and compared with the measured values. Experimental results demonstrate the proposed parameter identification method based on motor nameplate parameters and combining PSO optimization method is effective.
Application of the Bat Algorithm to Optimize the BP Neural Network
Authors: Xiao Hui Hui , Duan Yan Ming
Published: December 2014

For the standard BP algorithm usually has the limitations of slow convergence and local extreme values, a new method to adjust weights of BP network was proposed based on the bat algorithm of the global optimization ability and the strong convergence. The new algorithm was based on the weight adjustments of error back propagation of BP algorithm and the weight and threshold of BP network modification using the bats position update. The new algorithm can not only use the bat ability of global optimization, but also contain the feature of error back propagation of BP algorithm. The new algorithm was used in simulation test of two typical functions, results of which were analyzed and compared with that of basic BP algorithm and PSO-BP algorithm. Experimental results show that the new algorithm has faster convergence speed and higher convergence accuracy, and improved the learning ability and generalization ability of BP network. The performances of the new algorithm were superior to that of other 2 kinds of BP network algorithm.
The Multi-Site Joint Operation Method Based on Discharge Gate Ant Colony Algorithm
Authors: Liu Cong Cong , He Yi Cai , An Chang Peng
Published: December 2014

From the actual operation of the lock, respectively, with the objections to maximize utilization of the average chamber area and minimize average opening time and the product of the weight of the ship and minimize lock operating costs, it can make the use of AHP calculate the right target weight, so as to establish a multi-objective function model. Based on the constraints of each objection, it can be used improved ant colony algorithm for multi-site on the same river ship Joint operation, using MATLAB software for solving scheduling simulation, the results shows that the utilization and lock navigable levels have significantly improved . It proved this method can be used to optimize multi-site joint scheduling.
Vehicle Routing Problem Based on Heuristic Artificial Fish School Algorithm
Authors: Qin Lei , Li Ya Qin , Zhou Kang
Published: December 2014

Vehicle Routing Problem (VRP) is one of the core issue of logistics distribution, for traditional precision algorithms and heuristic algorithms had low accuracies or easily fell into local optimal solutions, it was difficult to obtain the optimal solution. This paper proposes a heuristic artificial fish school algorithm (HAFSA) for VRP, firstly, three-dimensional particle coding method is applied to vehicle routing code, and infeasible and inadequate artificial fish coding for heuristic repair, secondly HAFSA steps are given, finally the algorithm is tested through a simulative example. The experimental results show that compared with traditional genetic algorithm (GA) and particle swarm optimization (PSO), AFSA and their extension algorithms, HAFSA has a better performance in time and space cost and convergence.
The Design of the Minimum CPU System of TMS320VC54x
Authors: Qu Ai Ling , Ma Chang Lu , Qu Bing Bing
Published: December 2014

The minimum CPU system of TMS320VC54x DSP does not have redundant extended peripherals, it can work independently, perform real-time online simulation and burn program code. The paper mainly introduces the system design idea, the key points of design and matters needing attention, the paper offers the hardware circuit principle diagram of each unit of the minimum CPU system of TM320VC54x and the PCB diagram. The paper can work as the reference for the design of the minimum system of other CPU.
A Kind of Electric-Corona-Prevent Paint
Authors: Zhao Xia Yao
Published: December 2014

Based on the issue of the Corona Loss that generated in EHV and UHV transmission process, the work is about energy saving, emission reduction, and creates a kind of electric-corona-prevent paint which is suitable for both the super high pressure transmitting wires and metal equipment . The paint is consisted of RTV, charcoal and other additives. The basic theory is to cover the wires which are certain degree damaged with the paint by spraying. After that, we carry out some experiments on the covered and uncovered wires to contrast the loss of electric-corona. The results of the experiments show that, the wire covered by the electric-corona voltage and a lower loss of electric-corona than those without the paint, which proved the effect of the electric-corona-prevent paint well.
Research on High-Power, High-Speed Laser Modulation and Enlarge Experiment
Authors: Liu Hong , Zhan Wei Da
Published: December 2014

A laser modulation and amplification system is designed to meet the demand of long-range space optical communication, which uses the high-speed semiconductor laser to integrate electro-absorption (EA) modulator as a seed source. Two optical fiber amplifier technologies are used. The erbium-doped fiber amplifier (EDFA) and single-mode semiconductor laser pumping are used in the first-level; erbium ytterbium co-doped fiber amplifier (EYDFA) and 2-4 multimode fiber laser pumping with good temperature characteristics are used in the second level, and the control method is automatic gain control. The experimental result shows that the modulation rate achieves to 10Gbps, and the output optical power achieves to 5W.
PV Grid-Connected Inverter Islanding Detection Algorithm Improvements
Authors: Lu Chen , Sun Xiao Ming , Jin Yin
Published: December 2014

In a photovoltaic system, function of islanding detection is an essential part of inverter. The system should not only fast detect islanding, but also minimize the impact on power grid. The relationship between the output current THD and the time of detection is discussed. This problem is analyzed in this paper and a new algorithm is proposed. Based on the improved AFDPF algorithm, this method effectively regulate the relationships between the truncated coefficient (cf), current harmonic distortion and island detection time and on the basis of the results of simulation, the results of improved AFDPF algorithm are analyzed. Finally, the advantages and disadvantages are summarized.
Summary of Research Status of Active Power Filter
Authors: Wang Hai Yang
Published: December 2014

Due to the rapid development of modern rapid power electronics, power system harmonics are also increasingly serious harm, in order to effectively suppress harmonics to improve power quality, active power filter APF came into being, it can be effective for reactive power and frequency, amplitude harmonic changes are real-time tracking compensation. Currently, APF power electronics technology has become a major research topic. This article describes the basic working principle of harmonic current detection method and compensation current control method, the main circuit type of active power filter.
Research on the Key Factors of Mis-Operations and Correct Operations of the Residual Current Operated Protective Device
Authors: Shao Li Min , Zhang Meng , Du Song Huai
Published: December 2014

Residual Current Operated Devices (RCDs) are the protective instruments of safe operation for power system. RCDs are important components for safety against indirect contacts in low voltage installations, and employed for protection against electric shock and earth faults. In order to develop a new rule of RCD tripping directly by the human body current while shocking, it is very important to detect and identify the contact current of the human body in the summation leakage current on the low-voltage electric power grid. The new methods can solve the above problems of RCD. So, the tripping characteristics of a series of products from different RCD manufacturers were tested and analyzed under sinusoidal currents. Thus, it obtained the basic characteristics of the RCD and found out the rules and problems. The results of this study will be theoretical significant, and also can guide to developing intelligent instruments and equipment of RCD for smart grid.
Development and Research of MEMS
Authors: Wang Suo Cheng , Hao Yong Ping , Liu Shuang Jie
Published: December 2014

Microelectromechanical system (MEMS) is a new multi-disciplinary research field in recent years, which is an actuator or system composed of micro sensors, micro actuators, micro devices, signal processing system and control system. This paper mainly introduces the development of MEMS, technology characteristics, main processing materials and processing technology. At last it introduces the development and application of MEMS in the fuze system and aerospace system in detail for the future.
Capacitive Touch Sensing Principle and Application in the Car
Authors: Tao Qiu Xiang
Published: December 2014

Capacitance induction makes touch technology become more intuitive, can detect multiple fingers and at the same time to recognize gestures. This paper will introduce basic principle of capacitance induction and capacitance sensing technology in automotive applications. In this article introduces the structure of multi-touch screen and internal operations will be discussed after multi-touch induction to the change of human-machine interface (HMI).
Microcomputer Interface Experimental System Design
Authors: Cai Wen Jing , Peng Hong Sheng
Published: December 2014

The experiment is an important part in the learning of microcomputer control technology. This paper presents a set of microcomputer interface experimental platform, which based on VC++ interface software and control method, and combined with PCI panel and experiment box. This experimental system calls the functions in the dynamic link library of the PCI-7483 interface card through the self-developed experimental program, and makes use of the resources of PCI interface card to control the hardware experimental box, to complete the basic and the extensional experiments, and indicates and reflects the results of the experiment by the hardware experimental box. This experimental system can help optimize the experimental curricula, and improve the students' practical ability and analysis ability.
Research on Four Water-Filling Power Distribution Schemes in MU-MIMO System
Authors: Zhang Yong Bo , Li Jian Xin , Wen Wei Min
Published: December 2014

It is a key issue to distribute the total transmission power among different data streams leading to larger channel capacity or lower bit error rate at the base station in MU-MIMO system. Based on MU-MIMO system model applying block diagonalization precoding (BDP) this paper presented four kinds of water-filling power distribution schemes which had been simulated for random scheduling and multiuser scheduling. The simulation results showed that respective water-filling power distribution owned maximum channel capacity and united water-filling power distribution resulted in the lowest bit error rate (BER).
An Effective Multiple-Receiver SAS Range Doppler Algorithm Based on the Modified Range History Approximation
Authors: Tian Zhen , Tang Jin Song , Zhong He Ping
Published: December 2014

In order to solve the problem due to the double-square-root terms of the range history and degrade the phase error caused by the range history approximation, the method of displacement phase center approximation is modified continually and the range history is approximated into the sum of a monostatic term, a range-variant term and an azimuth-variant term. In the processing of deriving the azimuth phase stationary point using the conventional principle of stationary phase, the azimuth-variant term is considered sufficiently to obtain a more accurate phase stationary point. Thus, a more accurate point target response two-dimensional frequency expression is obtained. Based on that, a high resolution range Doppler algorithm for the multiple-receiver synthetic aperture sonar imaging is proposed. With the presented method, the echo signals corresponding to each receiver are processed firstly. Next, a high resolution SAS complex image can be obtained by coherently superposing each individual processing result. The result of simulation and real data imaging shows the effectiveness of the proposed algorithm.
Smoke Management System Design for Airport Terminal
Authors: Wang Liu Bing , Zhang Shu Ping
Published: December 2014

“Open Cabin” includes a solid roof which has enough fire resistance, covers over the entire region whose fire load is relatively high, such as commercial building with a large area. Performance design using “Open Cabin” concept of big space, is to protect areas whose fire load is relatively high from fire using the local fire protection measures (automatic alarm system, automatic sprinkler system, fire compartment and smoke resistance facilities), in order to make up fire protection measures which cannot be set in full range within big space. Then there is no need to separate big space physically for limiting the spread of fire and smoke.
The Study on DFS Algorithm of Unmanned Aerial Vehicle Platform Communications Relay System
Authors: Liu Hong Wei , Luo Wei Bing
Published: December 2014

This paper brings forward a new DFS algorithm in the unmanned aerial vehicle (UAV) platform communications relay system and gives the disposition processing. As a material application example, the paper simulates the algorithm. Compared to other algorithm, the result of simulation indicates that the new algorithm has these characteristics such as fast finding interference and steady changing frequency. The algorithm can satisfy request of system in complex communications environment and ensure Quality of Service (QoS) of system.
Method of Common View Based on Digital Satellite Television
Authors: Liu Xiao Long , Hua Yu , Xiang Yu , Liu Hui Qing
Published: December 2014

This paper apply satellite digital television signal for common view based on the DVB-S standard. By choosing some information from the signal as timing signal, we can get the arriving time of timing signal on local time scale. At last, we use the arriving time and some necessary correct massage to get the time difference between two locations.
Research on Near Space Optical Communication Transmitting and Receiving Technology
Authors: Zhan Wei Da , Xiao Dong Ya , Hao Zi Qiang , Li Hong Zuo
Published: December 2014

In near space optical communication, the laser beam energy affects communication link distance directly, also laser beam quality affects the laser energy density, modulation efficiency, bit error rate (BER) of communication and other parameters. In this paper we have presented an experiment system of space optical communication, of which the transmitting power is 1w, modulation rate is 500 Mbps and link distance is 8 to 10 kilometers. Then the effects of optical fiber collimator, electro-optic modulator, optical antenna and other units on beam power loss, beam diameter, divergence angle and other parameters are analyzed. Last we put forward the way of increasing the laser transmitting distance and the optimization measure of system key unit.
Software Defined Networking: A New Trend of Networking
Authors: Zheng Yao Rui , Shi Guo Wei , Luo Wei Bing , Gong An Min
Published: December 2014

Software defined networking is a new trend of Internet, having a great advantage over improving the ability of traditional networks. This paper introduced the background, definition and characteristics of this new trend, described its core-technology, and gave a prospect of this new technology.
Hybrid Mobile Power Supply Using PEMFC and Lithium Battery
Authors: Song Ni Jun , Qi Wei , Fang Jian , Liu Wei , Xiao Duo
Published: December 2014

A hybrid mobile power supply is developed based on air-cooled Proton Exchange Membrane Fuel Cell (PEMFC) and lithium battery. Pure fuel cell provides a rated output of 25W. With the assistance of lithium battery, the system provides instantaneous power of 50W. The system consists of fuel cell and its controller, lithium battery and its management circuit, power switching circuit, system control circuit and DC/DC convert circuit. The system is designed and realized, the measurement results show that the system works steadily below 50W.
Multi-Objective Programming Model for Joint Scheduling of Ships in the Complex Water Network
Authors: He Yi Cai , Liu Cong Cong , An Chang Peng
Published: December 2014

In the complex inland water network, under conditions sufficient to obtain waterway traffic load and ship information, according to the ship and scheduling department's diversity of demand, establish a multi-objective programming model for optimal navigation path selection, the use of linear weighting method to solve the optimal sailing consolidated path, reflecting the characteristics of the river network voyages information and target requirements diversity. Finally, an example preliminarily verified the rationality and validity of the model.
Research on Energy Saving in Cellular Networks Based on Dynamic Load Balancing
Authors: Xue Jian Bin , He Feng Jie , Liang Bo
Published: December 2014

In this paper, in order to balance the network load and make a part of the stations into the sleep mode, we adopted a load balancing scheme in relay-assisted cellular networks. In the proposed distributed algorithm, relay station only needs to exchange information with its neighboring which bases stations and makes a re-association decision by itself. So it can balance the load and decrease the call blocking probability, and then reduce the network energy consumption. According to the approach of tabu search, we can find the optimal mode combination and ensure the Qos (quality of service) which is presented.
Application of Process Migration in Intelligent Router Based on BLCR
Authors: Wang Tian Xi , Jiang Ming Hua , Liang Jing , Zhou Chang Long , Yu Feng , Wu Xi
Published: December 2014

Implement a checkpoint mechanism in the system of loaded BLCR project, to set up checkpoints on the progress which need a quick recovery. The router can receive and save the checkpoint files sent by the other system. When the process need to quickly migrate to the other machines, to use the checkpoint files to recover, ensure the process runs on the other computer from a previous running state. In this way can save a lot of time and resources, and can meet the need of many applications.
Channel Assignment Algorithm in Centralized WLAN
Authors: Dong Da Wei , Liu Xiao Guo , Jing Tian
Published: December 2014

To reduce the number of inter-disturb access points and the interference among access points in same channel, with research on interference issus and channel assignment algorithms of wireless local area network, a scheme suitable for centralized wireless local area network was proposed aiming to minimize the total interference among access points, which comprehensively considerate the number of neighbor and the received power. And then the algorithm with cases was simulated and analyzed, the result of NS2 simulation indicated that the algorithm was simple, effective and feasible, which could realize dynamic adjustment to the wireless LAN RF channel and had a better load balance effect among non-overlapping channels.
Integrity and Privacy Preserving Data Aggregation Algorithm for WSNs
Authors: Zhang Hua
Published: December 2014

This paper proposed an integrity and privacy preserving data aggregation algorithm for WSNs, which is called IPPDA. First, it attached a group of congruent numbers to the sensing data in order to execute integrity checking operated by sink node using Chinese remainder theorem (CRT); then it computed the hash function-based message authentication codes with time and key as the parameters to satisfy data freshness; finally, it adopted a homomorphic encryption scheme to provide privacy preserving. The simulation results show that IPPDA can effectively preserve data privacy, check data integrity, satisfy data freshness, and get accurate data aggregation results while having less computation and communication cost than iCPDA and iPDA.
Power Control Optimization for Position Tracking in Vehicle Network
Authors: Yang Zhe , Tan Guo Zhen , Zhang Fu Xin
Published: December 2014

We build an interference model to embody the influence from topological distribution, transmission power and packet transmission rate quantitatively. Then game theory is introduced. We take transmission power and position tracking accuracy as game strategy and payoff respectively. The existence of Nash equilibrium in vehicle network are proved. A Nash equilibrium is corresponding to the optimized transmission power vector for vehicles. Vehicle network self-adaptive power control algorithm (VNSPCA) is proposed to adjust transmission power in vehicle network. Finally, we conduct simulation and compare the performance of VNSPCA with MINPCA and MAXPCA.
Visualizing Interrupts and Replication with Timer
Authors: Pan Jian Sheng , Cheng Shi
Published: December 2014

Statisticians agree that signed epistemologies are an interesting new topic in the field of machine learning, and cyberneticists concur. Given the current status of pseudorandom configurations, cryptographers famously desire the refinement of simulated annealing. Our focus in this position paper is not on whether superblocks and extreme programming can collaborate to answer this quagmire, but rather on introducing a methodology for modular information (Timer).
An Effective Program Clustering Algorithm for TV Recommendation System
Authors: Cheng Chao , Liu Xin Yu , Wang Xing Jun
Published: December 2014

As the increasing popularity of smart TV, providing interactive and personalized TV video recommendation to TV viewers as on internet has been an urgent requirements for TV operators. To recommend a program to viewer satisfying individual interest, the classification of TV programs will be necessary, which should reflect the users' interests. This paper presents an approach for clustering TV programs with using users' VoD(Video on Demand) data. After analyzing the VoD data source, the VoD duration ratio is proposed as the measure of user's interest to a TV program. Through analyzing clustering result, it is observed of the implicit relation of user interest and we explained the relation.
A Robust Line Filter for Automatic X-Ray/CT Image Segmentation
Authors: Peng Shao Hu , Nam Hyun Do , Gan Yan Fen , Hu Xiao
Published: December 2014

Automatic segmentation of the line-like regions plays a very important role in the automatic recognition system, such as automatic cracks recognition in X-ray images, automatic vessels segmentation in CT images. In order to automatically segment line-like regions in the X-ray/CT images, this paper presents a robust line filter based on the local gray level variation and multiscale analysis. The proposed line filter makes usage of the local gray level and its local variation to enhance line-like regions in the X-ray/CT image, which can well overcome the problems of the image noises and non-uniform intensity of the images. For detecting various sizes of line-like regions, an image pyramid is constructed based on different neighboring distances, which enables the proposed filter to analyze different sizes of regions independently. Experimental results showed that the proposed line filter can well segment various sizes of line-like regions in the X-ray/CT images, which are with image noises and non-uniform intensity problems.
The Research Based on H.264 Embedded Video Systems of Optimized Compression Algorithm
Authors: Liu Yi , Cen Zhi Jun , Liu Jia
Published: December 2014

Analyzes the basic principles of H.264 video compression algorithm, such as integer DCT, multiple reference frame motion estimation, intra prediction, inter prediction; describes the characteristics of embedded systems, propose a feasible method of video signal optimization, by comparing with the experimental results, the influence of the H.264 coding bit rate bottleneck optimization function obtains a good result. These methods and ideas have practical significance, and it provides a strong reference for other development of video systems.
Effects of Zn on Microstructure and Mechanical Properties of Mg-6.0Zn-0.6Zr-1.0Y Magnesium Alloys
Authors: Li Quan , Zeng Bin , Zhu Wei Bo , Wang Si Ya , Jiang Xian Quan , Pan Fu Sheng
Published: December 2014

In this paper, Mg-6.0Zn-0.6Zr-1.0Y magnesium alloy for different levels of Zn extrusion test, and after extrusion products for the microstructure and mechanical properties of microscopic analysis, research Zn on Mg-6.0Zn-0.6Zr-1.0Y magnesium alloy extrusion and mechanism of influence of microstructure and mechanical properties, optimize the industrial extrusion products best optimum amount of Zn in Mg-6.0Zn-0.6Zr-1.0Y magnesium alloy.
Acoustic Properties of Magnetorheological Fluids under Magnetic Fields
Authors: Shen Min , Huang Qi Bai
Published: December 2014

Magneto-Rheological fluid (MRF) is a class of smart material who’s mechanical and rheological properties can be varied rapidly and reversibly by the applied magnetic field. MRF also exhibit fast, strong and reversible changes in the acoustic properties. The goal of this paper is to study the acoustic attenuation and velocity variation of the MRF composite under magnetic field. The model of acoustic wave propagation in MRF was established by Biot-Stoll theory. Some minor changes to the theory had to be applied, modeling both fluid-like and solid-like state of an MRF. The calculated results show that the attenuation coefficient of acoustic wave is improved obviously under the application of magnetic field in wide range frequency.
Vibrating Rechargeable Battery Design Research Based on the Two Kinds of Charging Ways
Authors: Shi Kai Lun
Published: December 2014

The project is innovative to convert vibration energy of low grade to high grade of electricity, achieved the purpose of saving energy and battery recycling. The built-in permanent magnet generator inside the battery can recharging the battery and external power supply when vibrating both took advantage of the vibration energy and ensure the reliable energy source of the battery. So it has great market prospect.
Collision Simulation and Analysis of Energy-Absorbing Box for Vehicle
Authors: Song Ke , Yang Bang Cheng
Published: December 2014

In order to improve the collision characteristics of energy-absorbing box and realize the optimization design, the collision simulation on energy-absorbing box is analyzed by LS-DYNA software. The collision characteristics including stress; strain; energy variation and deformation are analyzed for two kinds of main material; three different cross-sectional shapes and three different thicknesses in contrasts. Furthermore, energy-absorbing box has a smooth compression process effect through the improvement of structure. The simulation results may uncover the reasonability of the current design of energy-absorbing box and provide the basis for further improvement.
Development of Testing Machine for Measuring Unsteady State EHL Film under Heavy Load
Authors: Miao Nai Ming , Ding Jian Ning , Yang Ji Chang
Published: December 2014

In order to study elastohydrodynamic lubrication characteristics of cylindrical roller under heavy load and unsteady state, a testing machine is designed for measuring line contact film thickness and shape according to optical interference principle. The experimental apparatus is mainly made of glass block reciprocating motion systems, ball or roller rolling rotation system, loading system, speed control systems, lighting systems and image acquisition system. Moving parts is formed by the slider-crank mechanism. Specimen is accompanied by a pair of floating trial roller bearing. Specimen load is applied by leverage. The entrainment velocity of roller is approximate sinusoidal variation during a cycle. Experiment interference image is satisfactory, can provide reliable experimental data for future research.
Comparison of Quality of Braking Pads under Operational Conditions
Authors: Bernát Rastislav , Záležák Zoltán , Tkáč Zdenko
Published: December 2014

Taking into account vehicle safety, braking systems and their parts are subject to strict evaluation criteria not only due to market competitions of manufacturers but also from the customer point of view. The paper is focused on a subject research by comparing the qualitative properties of friction braking materials of vehicles under operational conditions considering the customer position. The research results containing the comparison and evaluation of friction braking materials could address the manufacturers who affect the product quality and complex manufacturing processes on the basis of real operational conditions. The final analysis and evaluation of braking pads was carried out on the basis of their wear directly under operational conditions by monitoring the material shortage and surface roughness of the friction material. We have selected and compared three types of friction materials within our research work which were applied to the Škoda Fabia 1,2 car under city traffic conditions. The research results lay stress on economic and qualitative indicators by selecting the correct braking pads taking into account the safety of vehicle operation.
Effect of Temperature on Dynamic Viscosity and Activation Energy of Milk and Acidophilus Milk
Authors: Hlaváč Peter , Božiková Monika
Published: December 2014

This article is focused on temperature dependencies of rheological parameters as the dynamic viscosity and activation energy of milk and acidophilus milk. Viscosity measurement was performed using a single-spindle viscometer. The relations of dynamic viscosity and activation energy in the temperature range 5–25 oC for milk and acidophilus milk were measured. The relations of all physical parameters of milk to temperature showed the influence of relative fat content. The effect of temperature on milk and acidophilus milk parameters is shown in Fig. 1–4. In the measured temperature interval, dynamic viscosities of milk ranged between 2.0 mPa.s and 1.3 mPa.s, and of acidophilus milk between 443.4 mPa.s and 244.1 mPa.s. Measured relations of dynamic viscosity for milk and acidophilus milk during temperature stabilisation had an exponential decreasing progress (Fig. 1–2), which is in accordance with Arrhenius equation. Temperature dependencies of activation energy are described by linear increasing functions (Fig. 3–4). Obtained values of activation energy were in the range 356.97–1267.70 J/mol for milk and in the range 615.94–2129.96 J/mol for acidophilus milk. The mathematical description of the dependencies is summarised by regression equations 2 and 3. Coefficients of regression equations and coefficients of determination approximately in the range 0.984–0.999 are presented in Table 1.
Transient Methods and their Usage for Flour Thermophysical Parameters Measurement
Authors: Božiková Monika , Hlaváč Peter
Published: December 2014

This article focuses on temperature relations of selected thermophysical parameters for three different types of wheat flour. The main objective of experiment was to determine the thermal conductivity, thermal diffusivity and volume specific heat of wheat flour produced in Slovakia. Measurements were performed in laboratory settings. Thermal parameters were measured by the thermal analyser Isomet 2104 with two types of probes – a linear probe and plane probe. Measurement by the linear probe is based on the hot wire method, and measurement by the plane probe is based on the extended dynamic plane source method. Both methods are described in the text. Two types of measurement methods were used because of the non-homogenous structure of measured material. All thermophysical parameters were measured during the temperature stabilisation in the temperature interval 5–24 °C. Obtained graphical relations had linear increasing progresses with high values of determination coefficients in all cases.
Effect of Strain Rate on Mechanical Properties of Two-Component Epoxy Adhesive Bond
Authors: Cidlina Jan , Žarnovský Jozef , Müller Miroslav
Published: December 2014

In practice, adhesive bonded joints are loaded by different intensity and rate. In the case where bond bearing capacity is exceeded, failure occurs. One of the affecting factors is strain rate. In the laboratory tests, ČSN EN 1465 is used as a basic standard, specifying the rate of deformation in the interval of 65±20 seconds. The goal of this research is to describe the behaviour of two-part epoxy adhesives at different strain rate of bonded joints. Experiments evaluated the changes of bond strength, deformation and time to failure. Time to failure is particularly significant because of the potential consequences of fast structural joint violation.
Effect of Pre-Heating Temperature on Microstructure and Properties of 22MnB5 Steel Hot Stamping
Authors: Li Ping , Liu Yu Sheng , Gongzi Tian Zong , Xue Ke Min
Published: December 2014

The hot stamping process of ultra high strength steel(UHSS) sheet is an innovative way to manufacture the components with a ultra high tensile strength. The sufficiency of martensitic transformation in formed component is affected by pre-heating temperature of blank directly. In this paper, experiments of heating UHSS blanks to 700°C, 800°C, 900°C and 1000°C were implemented to investigate the effect of pre-heating temperature on the formed component’s microstructure and mechanical properties. The results indicate that 900°C is the best pre-heating temperature for hot stamping process. The microstructure of formed component is all fine and uniform martensite. Meanwhile, tensile strength and vickers hardness raise up to 1580MPa and 450HV, respectively.
Research on Resistance Spot Welding Process of Hot-Stamped Steel BTR165
Authors: Fang You Zhen
Published: December 2014

Resistance spot welding of BTR165 was applied to study property of its joint by using power-frequency alternating current welding equipments. The tension strength, hardness distribution, microstructure and tensile fracture appearance were analyzed. The test results show that the hot-stamped steel has good weldability and could obtain better performance by optimizing technology. The microstructure of spot welded metal is martensite (M), tensile failure mode is button pull-out fracture, The fracture morphology has plastic dimple characteristic.
Research on Resistance Spot Welding Property of Hot-Stamping Quenched Steel Sheets
Authors: Zhang Jun Ping , Feng Yi , Song Lei Feng , Wang Guang Yao , Jin Qing Sheng
Published: December 2014

22MnMoB hot-stamping quenched steel sheets were well welded together by power frequency spot welder with optimization of relevant welding parameters in this paper. According to the experiment results of welding spatter, maximum shearing force and the size of nugget, the effects of welding current, welding time and electrode pressure on weld property were advanced. The results show that while welding current, welding time and electrode pressure are respectively set as 6.0~6.5kA, 0.5~0.7s and 4~7kN, the weld exhibits good mechanical property. The nugget diameter appears approximate linear relationship with mechanical property of weld and determines the fracture model of welds. The novel hot stamping steel sheets exhibit good welding property. The optimizing welding parameters can be used to instruct the practical production.
Hot Deformation of Al - 4.5 Mass % Mg Alloy Sheet
Authors: Zhao Pi Zhi , Sakai Taku , Anami Toshiya
Published: December 2014

Hot deformation of an Al - 4.5 Mg alloy was studied in tension at temperatures of 663 K to 753 K and at strain rates ranging from 10-5to 10-1s-1. Large total elongations of 150 % - 180 % were obtained under deformation conditions for the appearance of yield point phenomenon, where the corresponding stress exponent was ~3. It was discussed that solute-drag dislocation glide mechanism can operate under these conditions and result in large tensile ductility. In addition, dynamic recovery also affects the hot ductility.
Martensitic Automotive Steel Sheet - Fundamentals and Metallurgical Optimization Strategies
Authors: Mohrbacher Hardy
Published: December 2014

Martensitic sheet steel is increasingly being used in advanced car body construction, especially in areas where high crash loads are expected. Using such steels appropriately the weight of individual components can be reduced by up to 20 percent. Martensitic steel sheet is commercially available in the strength range of 1200 to 1900 MPa, either as cold forming or hot stamping grade. Whereas the strength of such martensitic steels is practically only a function of the carbon content, other properties such as ductility, toughness, bendability and delayed cracking resistance are severely influenced by other alloying elements and the particular thermal processing route. The paper discusses the influence of various key-alloying elements such as Nb, Mo and B on these properties and suggests routes to optimize the steel’s behavior with respect to the manufacturing and application related aspects.Keywords Martensite, prior austenite grain size, delayed cracking, grain boundary segregation, hydrogen trapping, niobium, molybdenum
Investigation on Properties and Microstructure in Hot Stamping Operation of Rear Axle Beams
Authors: Jin Xiao Chun , Xue Yong Shen , Ma Qing Nan , Zhang Mei , Li Lin
Published: December 2014

In the automotive industry, the hot forming of high strength steels offers the possibility to obtain significant reduction of weight without affecting the structural performances of final products. The main reason of its restricted application in the industry lies however in the lack of basic knowledge about mechanical and microstructural characteristics of sheets at elevated temperature, boundary conditions, and other process parameters. To partially overcome this limitation, this paper presents a research on the material properties of the hot stamping steel 22MnB5. Sheets of boron steel 22MnB5 with a thickness of 3.8mm were investigated and the results of experimental hot stamping tests were considered. The yield strength (YS) reached about 1200MPa, tensile strength (TS) reached 1500MPa, microhardness reached over 450HV at heating temperature of 880°C and holding 5 min.
Research and Progress of Hot Stamping in China
Authors: Ma Ming Tu , Zhang Yi Sheng , Song Lei Feng , Wang Yi Lin
Published: December 2014

This paper introduced the significance of hot stamping on developing lightweight technology and safety property enhancement in China Automotive industry, as well as the research status and progress and market prospect of hot stamping process, Materials and equipments. Key technology and focus of hot stamping are analyzed, direction of hot stamping further development were proposed. Hot stamping process, technology and equipments with completely independent intellectual property rights were developed surrounding energy saving, process stability, quality consistency, flexible distribution of components’ strength , high cost-effective production and so on, which is of important for development of hot stamping in China.
Research Status of Advanced Hot Forming Technology
Authors: Xu Wei Li , Huang Zong Bin , Wan Yong Hong
Published: December 2014

For the past decade, BaoSteel has been working on the development of press hardened steels (PHS) and hotforming (HF) technologies, aiming to provide technical package solutions for customers and made some achievements. In this paper, the latest research development on advanced hotforming processes such as patchwork, tailored property, door ring and low-cost short-cycle was introduced.
Robustness of the Tailored Hot Stamping Process
Authors: Rolfe Bernard , Abdollahpoor Amir , Chen Xiang Jun , Pereira Michael , Xiao Na Min
Published: December 2014

The final mechanical properties of hot stamped components are affected by many process and material parameters due to the multidisciplinary nature of this thermal-mechanical-metallurgical process. The phase transformation, which depends on the temperature field and history, determines the final microstructure and consequently the final mechanical properties. Tailored hot stamping parts – where the cooling rates are locally chosen to achieve structures with graded properties – has been increasingly adopted in the automotive industry. Robustness of the final part properties is more critical than in the conventional hot stamping. In this paper, the robustness of a tailored hot stamping set-up is investigated. The results show that tailored hot stamping is very sensitive to tooling temperature, followed by latent heat radiation emissivity, and convection film coefficient. Traditional hot stamping has higher robustness compared to tailored hot stamping, with respect to the stamped component’s final material properties (i.e. phase fraction, hardness).
Hot Stamping High Strength Steel Spot Welding Technology and Quality Evaluation of Welding Joint
Authors: Hao Su Feng , Shan Zhong De , Chen Shu Jun , Jiang Chao
Published: December 2014

The heterogeneity of microstructure and mechanical performance of welding joints were affected by unique material properties such as high resistivity and low thermal conductivity, instantaneous high temperature of spot welding thermal cycle, and uneven local cooling rate. Because of ultra high strength of hot stamping parts, the welding joint is more inclined to fail as the failure mode of interfacial fracture, the traditional critical nugget formula fell down. Through designing orthogonal experiment, the effect of different welding parameters on joint performance was analyzed, the optimized welding process was obtained; on account of the quality evaluation of welding joint, nugget spherical mode was built to separately analyze the stress condition of welding joint in the failure modes of interfacial fracture and nugget pull-out, the new evaluation criterion aimed at high strength steel was established. Two kinds of 1.2 mm and 2.0 mm steels were used to validate the critical weld diameter. Results showed that the critical formula could accurately evaluate failure of the weld joints.
Valuation Method for Effects of Hot Stamping Parameters on Tailored Properties
Authors: Wang Zi Jian , Xu Ya , Zhou Ming Lin , Wang Yi Lin , Zhang Yi Sheng
Published: December 2014

The effects of hot stamping parameters including die temperature and holding pressure was evaluated throughout the orthogonal experiment method. Regardless of the effect of the holding pressure, when the die temperature was lower than 400 °C, the lowest hardness emerged at the air gap. The range of transition zone expanded as the die temperature increased. When the die temperature was set at 400 °C, the hardness with 20MPa holding pressure was higher than others, which resulted by considering both the effect of cooling rate and strain.