bluuebunny/crossref_metadata_2025 huggingface dataset:
Experiment on Mechanical Behavior of Reinforced Concrete Subjected to Impact Loading
Authors: Liu Hai Feng , Yang Wei Wu , Ning Jian Guo
Published: February 2012

The dynamic compression tests of reinforced concrete with different reinforcement ratios are carried out by split Hopkinson pressure bar (SHPB). Reinforced steel bar is placed along longitudinal and transverse direction. Experimental results show that reinforced concrete is non-linear and rate-dependent. With the enhancement of strain rate, the peak stress of reinforced concrete increases correspondingly
Design of Universal Electronic Cash Payment System
Authors: Jia Ping
Published: February 2012

This dissertation introduces the design of an off-line anonymity-controllable universal electronic cash payment system, which can prevent double spending. The system is comprised of user end system, business e-wallet system and bank electronic cash server system.
Study on Affecting Factors of the Wear Reliability Based on PHM to Aircraft Airfoil’s Slide Rail
Authors: Bai Wen Hua , Zuo Hong Fu , Cai Jing , Lv De Feng
Published: February 2012

The slide rail of the airfoil is the key structural component of the aircraft, and its wear reliability has important impact to the aircraft security. The traditional method to the slide rail wear reliability analysis is based on time parameter to establish the reliability function. In fact, the actual operating and environmental parameters in the slide rails have an important impact on its reliability. The proportional hazards model (PHM) method is proposed to study the affecting factors of the slide rail’s wear reliability; the method of principal component is used to make a quantitative description to those affecting factors. and the slide rail’s reliability model of its failure function and life distribution function are obtained under many factors affecting. Finally, a study is made to the wear reliability of some regional jet’s slide rail with the PHM method; the wear reliability model is got under the contact stress, hardness and roughness three affecting factors which meet the fact. So the more accurate wear reliability models can be got by the PHM methods, and that has a practical significance to improve the overall reliability of the aircraft.
The NC Processing of the Transitional Region of Free Surface Based on Section Method
Authors: Wu Zai Xin , Li Te , Wang Ya Zhou , Hu Chi Bing
Published: February 2012

The machining of transitional region of free surface is a kind of very important machining technique. Because of the complicated shape of the transitional region of free surface, it is very easy for cutting tool to dry cutting with machined surface. In order to machin-transitional region of free surface, using the method of curves of cross sections base on CNC machining theories and technology of mechanical manufacture. And researching ball tool path generation, a improving method for building tool path of interface-free was raised, and using this method to do some machining simulation at last.
Application of Virtual Simulation Technology in Fusion Engineering
Authors: Lei Ming Zhun , Song Yun Tao , Wang Song Ke
Published: February 2012

Nuclear fusion is one of the most important ways to resolve human energy issues. The main structure of nuclear fusion device and its functions are introduced in this article. Virtual simulation technology has been used in the process of the conceptual design, detailed design and optimization of the fusion device structure. Electromagnetic analysis of the ITER feeder system show the specific application of virtual simulation technology in nuclear fusion engineering, as well as the thermal analysis of ITER thermal shield. It verifies the importance of virtual simulation technology.
Analysis of Energy Saving Effect of Solar Light Pipe Systems in Beijing Olympic Buildings
Authors: Wu Yan Peng , Li Jing
Published: February 2012

In response to the concept of Olympics, Beijing Olympic buildings use solar light pipe systems for daylighting, such as the underground passage in the Olympic Forest Park and the gymnasium of University of Science and Technology Beijing. In this paper, the solar light pipe systems in the two buildings have been measured to find out whether indoor daylighting performance can meet daily use requirements. At last, compare the result with T8 fluorescent lamps to get the energy saving effect of two buildings. Calculating results showed that indoor illuminance of the two buildings can achieve daily use requirements when external illuminance reaches 25036lx and17895lx, and the amount of electricity that can be saved are 2514KW•h and 22186KW•h per year.
The Comparison of Portal Frame Design by Penalty Function Optimization and Traditional Method
Authors: Lin Xian Gen , Xu Yong
Published: February 2012

The comparison of portal frame design by penalty function optimization and traditional method aim at 30m span portal frame with tapered members was made. It was found that the essence of optimization design was to research the reasonable distributing of sections, through the interaction between capacity and key section parameters the optimization design were realized. Now the idea of green and less energy is fashionable, then optimization design is very significant in practical engineering. According to engineering statistics the optimization design can reduce 15%~30% of material quantity. In this article the selection of parameters during optimization design was expounded.
A New Remote Video Monitoring Network System Based on Protocol Detection and Video Compression Identification
Authors: Zhou Zhi Zheng , Xu Ru Zhi , Jiang Shu Ming
Published: February 2012

This paper presents a method that can achieve the centralized management, unified monitoring and interactivity throughout the network for monitoring equipments of different manufacturers. This method achieves the automatic detection and extraction of different monitoring equipments communication protocols by capturing and analyzing the network packet. And it also achieves dynamic self-adaptive adjustment of resolution and flow-speed of audio and video data by dynamic analysis. The design implements a software system of distributed heterogeneous network and remote video surveillance, and achieves remote centralized management of video surveillance equipment which not provides compatible development kits.
Comparison of Supply Chain Consigning Collaborative Innovation Modes
Authors: Tian Wei , Zhou Li
Published: February 2012

In this paper, we have constructed supply chain consigning collaborative innovation modes and explored the innovation game process involving supplier, manufacturer and third-party research firm where the manufacturer acting as a core firm. We consider innovation cost coefficient information symmetry and asymmetry. The research shows that supplier’s innovation effect is more direct to supply chain. When innovation ability is similar, no matter judging from innovation inputs, expect profits or demand quantities, the mode of the supplier consigning innovation is superior to that with third-party and non-collaborative innovation.
Basic Principles and New Methods on Emotional Product Design
Authors: Huang Min , Qiao Hong Juan
Published: February 2012

Emotional design is one of the most important methods in modern product design. It was highlighted after Donald A. Norman published his book Emotional design: why we love (or hate) everyday things. Emotional design addresses people’s needs and hopes which is in the center of the development of product design and product technology. Due to the lack of strong theoretical basis and quantitative analysis, many products can’t reach the goal of their designers with Emotional feelings, nor can consumer’s emotional understandings be similar to the designers’ emotional expectations. This paper analyzes the concept of emotional design and some difficulties which designers must to be faced in their emotional designing works, discusses on product shape design according to emotional design. On this basis, the Kansei engineering and emotional design methods are described in details.
Effect of Flow Exit Angle and Blade Height on the Temperature Distribution of a Typical Gas Turbine Rotor Blade
Authors: Poursaeidi Esmail , Mohammadi Maryam , Khamesi Seyed Sina
Published: February 2012

One of the major factors which have important effects in turbine blade designing is temperature distribution and its heat transfer rate. The temperature distribution in blades depends on many factors; one of the most important ones is the geometry of the blades. In this paper by continuing some previous findings about the geometry[1], an optimized blade and a real one are compared from the thermally aspect view. Flow exit angle of the rotor blade and the blade height are two parameters which have direct effect on the heat transfer rate. The presented temperature distribution is solved based on the new flow exit angle of rotor blade. By optimizing the flow exit angle for the first time, the blade height is computed. By solving mathematically and thermodynamically relations and writing a solving code based on the finite volume method, the temperature and the heat transfer rate are computed numerically. These results shows the direct effect of flow exit angle on temperature distribution which can be used for upgrading the turbine efficiency.
Influence of Different Gradation Carbonyl Iron Particles on the Properties of Magneto-Rheological Fluids
Authors: Du Cheng Bin , Yu Guo Jun , Gong Zhi Wei
Published: February 2012

The influence of carbonyl iron particles sizes on the properties of magneto-rheological fluids (MRFs) were studied. Different-sized carbonyl iron magnetic particles were prepared by ball milling with different milling times. On this basis, different particle MRF were prepared The off-state viscosity and the shear stress of the above MRFs were characterised and studied by an advanced rotational rheometer system. The test results show that the off-state viscosity and the shear stress of single-particle MRFs were enhanced with increasing average carbonyl iron particle size at a constant magnetic field. The shear stresses of MRFs containing two or three different particle sizes were significantly improved compared with the MRFs containing only a single particle size. At a reasonable level of medium and small size carbonyl iron particle spread throughout the structure of the multiple-particle MRFs, the defects in the chain structure were remedied when a chain reaction occurred, and the mechanical properties of MRFs were enhanced. Meanwhile, increased mass fractions of the small size carbonyl iron particle resulted in a reduction in overall average particle size of MRFs, and the mechanical properties of MRFs were also reduced. The mechanical properties of multiple-particle MRFs were observed to be strongly dependent on the size and mass fraction of the medium and small carbonyl iron particles.
The Effect of Surface Modifier on the Mechanical Properties of the Oxysulfate Whiskers/PP Composites
Authors: Jiang Yu Zhi , Zhang Li Li , Zhang Zhong Yang
Published: February 2012

The magnesium oxysulfate whiskers/PP composites were prepared by melt-extrusion with modified whiskers as fillers. The mechanical performances including the tensile strength, elongation at break and elastic modulus were tested by electronic universal testing machine.The effect of surface modifier on the mechanical properties of the composites was studied. In general, the mechanical properties of the composites of the zinc stearate modified whiskers/PP were better than it modified by coupling agent KH550. when the contents of the whiskers modified were 20%, the mechanical properties of the composites got the best. There occurred different organic molecule membranes on the surface of the modified whiskers, which lowered the interfacial energy of whiskers. So modified whiskers had different strengthening with PP matrix.
Experimental Study on Flotation Process Conditions of Lead-Zinc Ore
Authors: Li Ming Ming , Zhang Qi Dong
Published: February 2012

On the basis of analyzing sample properties of lead-zinc ore, the optimum experimental condition combination was obtained from systematic experimental studies of the conditions. The experimental condition combination was validated by the full process closed-circuit experiment, which showed that the good separation indexes on lead grade of 59.78% in lead concentrates, the lead recovery of 87.50%, and zinc concentrate grade of 56.33%, the zinc recovery of 93.60%, and sulfur concentrate contained 0.50% of lead, 0.47% of zinc.
Microstructural of Cr/MWCNT Composites and its Catalysis in Synthesis of Biodiesel
Authors: Fan Xue Hai , Xiao Guo Min
Published: February 2012

Multi-walled carbon nanotubes (MWCNTs), potassium dichromate (K2Cr2O7) and sulphuric acid were used for the preparation of Cr/MWCNT composite by impregnation method. The composites were comprehensively characterized by transmission electron microscopy （TEM），energy dispersive X-ray analysis (EDX), infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and thermal gravity analysis (TGA). Due to its unique electrical and structural properties, this composite was applied to the synthesis of biodiesel (FAME) as a catalyst, showing effectively catalytic performance.
Synthesis, Characterization and Photocatalytic Activity of Nb-Doped TiO2 Nanoparticles
Authors: Li Xuan Dong , Han Xi Jiang , Wang Wen Ying , Liu Xiao Hong , Wang Yan , Liu Xin Rong
Published: February 2012

Nb-doped TiO2 powders with different concentrations of Nb have been synthesized by a sol-gel method and characterized by a series of technologies including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV-vis spectroscopy. The photocatalytic activity of Nb-doped TiO2 is evaluated by degradation efficiency of methyl orange in aqueous solution. The results indicate that the photocatalytic activity of Nb-doped TiO2 synthesized with a Nb/Ti molar ratio of 5% is higher than that of TiO2 under the visible light.
Gear Fault Diagnosis with Support Vector Machine
Authors: Tang Jia Li , Huang Chen Rong , Zuo Jian Min
Published: February 2012

Because of the complexity of gear working condition, there are non-linear relationship between characteristic parameters and fault types. This paper proposes to apply the Support Vector Machine to set up the nonlinear mapping to solve the difficulties of gear fault diagnosis. Taking a certain gearbox fault signal acquisition experimental system for instance, Matlab software and its neural network toolbox are used to model and simulate. The simulation result shows the founded model has preferable learning and generalization capabilities, which performs effectively in the common gear fault diagnosis and it can identify various types of faults stably and accurately.
Study on the Inclusion Complex of Rutin/Sulfobutylether-β-Cyclodextrin
Authors: Zhou Cai Ju , Li Li Fang , Liu Ying , Wen Shao Peng , Guo Yong En , Niu Xiao Guang
Published: February 2012

The inclusion complexes of rutin/sulfobutylether-β-cyclodextrin (SBE-β-CD) were prepared by grinding, co-precipitation and ultrasonic method and then identified with differential scanning calorimetry (DSC) and UV-visible spectrophotometry (UV). The molar ratio 1∶1 of rutin to SBE-β-CD in the complex was confirmed by phase solubility studies, and the dissolutions of rutin/SBE-β-CD were investigated by UV. The dissolution of rutin included in the complex showed significant increases in aqueous solution. The rutin/SBE-β-CD inclusion complex exhibited unique physical characteristics that are different from rutin.
Treatment of Waste Phosphoric Acid Containing Metal Ions by Electrodialysis
Authors: Sun Guo Fu , Xu Jing Li
Published: February 2012

The electrodialysis mehtod was used to treat waste phosphoric acid containing Al and Mo ions in this study. The feasibility study of elctrodialysis for treatment of the waste phosphoric acid containing metal ions was investigated. The voltage, solution concentration and feed temperature mainly affect electrodialysis of the phosphoric acid containing Al and Mo ions. Higher voltage and feed temperature are beneficial for desalination of Al and Mo ions. At least, 30% of Al ions and 7% of Mo ions can be removed from the phosphoric acid by using the CMX/AMX, CM1/AM1 and CMX-SB/ACS ion-exchange membranes. An electrodialysis process seems to be a promising process to treat waste phosphoric acid containing Al and Mo ions.
Stress Relaxation Continuum Damage Constitutive Equations for Relaxation Performance Prediction
Authors: Guo Jin Quan , Zhang Wei , Sun Xiao Hong
Published: February 2012

Stress relaxation constitutive equations based on Continuum Damage Mechanics, Kachanov-Robatnov creep model, and stress relaxation equation has been developed by analyzing stress relaxation damage mechanisms and considering the relationship that stress relaxation is creep at various stresses. And, the constitutive differential equations were integrated to predict stress relaxation performance by using numerical analysis technique. In order to validate the approach, the predicted results are compared to the experimental results of uni-axial isothermal stress relaxation tests conducted on 1Cr10NiMoW2VNbN steel with the same temperature of creep tests. Good agreement between results of relaxation tests and the predicted results indicates that the developed constitutive models can be used in the relaxation behavior evaluation of high temperature materials.
Research on Design Methods and Aerodynamics Performance of CQU-DTU-B21 Airfoil
Authors: Chen Jin , Cheng Jiang Tao , Shen Wen Zhong
Published: February 2012

This paper presents the design methods of CQU-DTU-B21 airfoil for wind turbine. Compared with the traditional method of inverse design, the new method is described directly by a compound objective function to balance several conflicting requirements for design wind turbine airfoils, which based on design theory of airfoil profiles, blade element momentum (BEM) theory and airfoil Self-Noise prediction model. And then an optimization model with the target of maximum power performance on a 2D airfoil and low noise emission of design ranges for angle of attack has been developed for designing CQU-DTU-B21 airfoil. To validate the optimization results, the comparison of the aerodynamics performance by XFOIL and wind tunnels test respectively at Re=3×106 is made between the CQU-DTU-B21 and DU93-W-210 which is widely used in wind turbines.
Stability Analysis of Perilous Rock in Views of Damage and Fracture Mechanics
Authors: Chen Hong Kai , Tang Hong Mei , He Xiao Ying
Published: February 2012

Perilous rock rupture is dominated by damage and fracture of the dominant fissure. Define factor of safety of perilous rock as the ratio of the damage fracture tenacity at the end area of the dominant fissure to the union fracture strength factor; Transfer loads acting on perilous rock to the dominant fissure, and divide them into four components, i.e., water pressure in fissure, average shear stress, moment around the end of the dominant fissure, and average tension stress, further, contribute methods to calculate fracture strength factor every components in view of fracture mechanics; Based on these individual fracture strength factors, establish the method to calculate the union fracture strength factor along fracture orientation near the end area of the dominant fissure. Further, on the basis of damage duration of the dominant fissure, provide the formula to solve the fracture tenacity of rock in damage area near the end of the dominant fissure in detal. Case analyses identify that it is reasonable to consider orientation earthquake force in stability analysis of perilous rock, which promulgates the stability status of perilous rock more effective than that by the limit equilibrium principle.
Frequency and Pressure Characteristics of a Helmholtz-Type Valveless Self-Excited Pulse Combustor
Authors: Xu Yan Ying , Zhai Ming , Dong Peng , Wang Fei , Peng San Long , Zhu Qun Yi
Published: February 2012

The frequency and pressure characteristics of a Helmholtz-type valveless self-excited pulse combustor with continuous supply of fuel and air are investigated in this paper. A theoretical model of combustion is established. In the model, combustion is assumed to take place in a thin flame sheet separating the two zones, and the effects of the continuous gas-supply mode and heat transfer of the tailpipe on the operating characteristics are considered. From the mathematical model, the expressions of frequency and maximum pressure amplitude for the pulse combustor are derived. The results suggest that the frequency decreases with the increase of excess air ratio and tailpipe length, and increases with the heat load. The pressure amplitude increases with the increase of the excess air ratio and heat load, and slightly declines with the increase of the tailpipe length. The experimental data show qualitative agreement with the calculated results.
Fatigue Life Study of Hatch Corner on Large Bulk Carrier
Authors: Sun Shu Li , Xie Yong He , Zhang Jun
Published: February 2012

The fatigue life study of the hatch corner plays very important roles in design of hatch corner. The target function is the gravity of the hatch corner, and the constraint function is fatigue accumulation damage in the present paper. The structure optimal design theory has been combined with the fatigue life assessment method, to assess a hatch corner fatigue life of a large bulk carrier, and to optimize the hatch corner based on meeting the fatigue life. The hatch corner has been optimized under meeting yield strength and buckling strength. The numerical results show that the optimum method is fit to optimize the hatch corner.
Mining Mobile Phone Messages in Mobile Social Network
Authors: Cui Wen
Published: February 2012

A mobile social network plays an essential role as the spread of information and relationship. Mining the popular P2P messages in a short period of time is very valuable. Traditional mining method is not suitable for this very large scale dataset. In this paper, we present a mining approach based on MapReduce parallel framework. We use our metric to analyze point-to-point (p2p) messages within an organization to extract social hierarchy. We analyze the behavior of the communication patterns with taking into account the actual communication messages sent by users. Experimental results show that the final dataset of popular messages is very small with high sending coverage ratio. Empirical studies on a large real-world mobile social network show that performance of our algorithm.
The Simulation Research of above Knee Intelligent Prosthesis Based on Computed Torque
Authors: Xie Hua Long , Zhu Zong Xiao , Zhang Wen Ke , Li Fei
Published: February 2012

The above knee (A/K) intelligent prosthesis controlled by magneto-rheological (MR) damper can compensate the basic movement function of amputees. This paper analyzed the existing torque devices of knee joint and introduced the configuration of A/K intelligent prosthesis controlled by MR damper. Dynamics model was given and virtual prototype was established. The control method based on computed torque was discussed and combined control simulation was done. The result indicates that A/K intelligent prosthesis controlled by MR damper can track human normal gait well.
Measurement of LED Spatial Intensity Distribution Using Imaging
Authors: Shen Huan Bo , Chen Qing Guang , Lin Bin
Published: February 2012

This paper, through studying of LED luminescence properties, presents a fast measurement method and device of LED sources spatial intensity distribution. This method is based on planar imaging, and it has significant merits of fast, easy operated, informative and real–time. The basic structure is LED luminous energy converges on image space through optical lens of a certain numerical aperture(NA). In image space, the energy on the defocused plane is collected with the imaging detector. Then, calculating energy distribution on object virtual plane from that on the image space defocused plane through imaging relationship. Thus, each point of the LED luminous intensity distribution on object virtual plane can be calculated. Tracepro simulation software is used to simulate energy distribution of the model, and the corresponding data analysis shows that planar imaging can accurately reflect the distribution of the LED light. This method has practical meanings for luminous flux measurement of some LEDs.
Study on Shape Memory Alloy Plate with Circular Hole under Biaxial Uneven Tension
Authors: Zhou Bo , Li Xu Kun , Hou Gang Ling
Published: February 2012

This paper focuses on the thermo-mechanical behaviors of a shape memory alloy (SMA) plate with a circular hole under biaxial uneven tension. The phase transformation behaviors of SMA under complex stress state are formulated based on the one-dimensional phase transformation model developed by Zhou and Yoon. The stress field equation of the SMA plate with a circular hole is derived according to linear elastic mechanics. The phase transformation behaviors near the region around the circular hole are numerically simulated under different conditions of applied stress.
Cyclostationary Analysis Based Gear Fault Diagnosis
Authors: Li Zhen Tao , Li Hui
Published: February 2012

Gearbox vibrations acquired by sensors are random cyclostationary signals, which are a combination of periodic and random processes due to the machine’s rotation cycle and interaction with the real world. Since the spectral structure of a gear vibration signal is mainly characterized by the interaction between the meshing harmonics and their sidebands, the spectral correlation density (SCD) function has been applied to gear monitoring. This approach is capable of completely extracting the fault characteristic frequencies related to the defect. This gives a desirable ability to detect the singularity characteristic of a signal precisely. This technique permits both fault detection and identification of the damaged gear. The experimental results show that the proposed method based on cyclostationary analysis can effectively diagnose the faults of gear.
Studies on Predicting Distribution of Guava Fruit Fly in Yunnan Province Based on the Genetic Neural Model
Authors: Ni Yuan Ping , Liu Xiao Fei , Ye Hui
Published: February 2012

Based on discussing the advantages of improving genetic algorithm and analyzing the defects of back propagation neural network, we presented the genetic neural model. The simulating data proved that the genetic neural model was able to realize parallel search and could get faster searching speed during random searching optimizaiton. The model was applied to predicting distribution of guava fruit fly. The experimental results show that the model can predict distribution of the fly which is consistent with the practical distribution. The model is very useful in practice. It is worthwhile to refer the model to predicting similar insects.
Non-Isolated Bidirectional DC-DC Converter with Step up-down Capability Based on Energy Materials
Authors: Do Hyun Lark
Published: February 2012

A non-isolated bidirectional DC-DC cconverter with step up-down capability is proposed in this paper. The proposed converter operates with a fixed switching frequency and has a step up-down capability regardless of the direction of power flow. Voltage stresses of the power switches are lower than those in the conventional buck-boost converter. Moreover, only a single magnetic component is required in the proposed converter. An asymmetrical pulse width modulation (APWM) control shceme is utilized. The operation principle and steady-state analysis of the proposed converter are provided. A prototype of the proposed converter is developed, and its experimental results are presented for validation
Simulation Research on Direct 3D ECT Imaging Based on 16 Electrodes
Authors: Yan Hua , Qiang Da Zhuang , Wang Yi Fan
Published: February 2012

Electrical capacitance tomography (ECT) attempts to visualise the permittivity distribution inside a vessel by measuring capacitances between pairs of electrodes, which are placed around the periphery of the vessel. In this work, direct 3D ECT imaging based on 16 electrodes was researched. These electrodes were arranged in four planes. Every four electrodes on each plane were rotated 0 (sensor 1) or 45 (sensor 2) with reference to the previous. Using finite element analysis, the sensor sensitivity distributions and simulation data of capacitance measurements were obtained. And then 3D images were reconstructed directly by using linear back projection (LBP). Simulation research shows that sensor 2 is better because it has better reconstruction quality and lower requirement for the dynamic range of capacitance measurement circuit
Simulation and Optimize Design for Deflector Plate of the Vehicle Mounted Vertically Thermal Launched Missile
Authors: Yu Shao Zhen , Jiang Yi , Ma Yan Li , Ma Yan Yan , Liu Bo Wei
Published: February 2012

In this dissertation, academic analysis of the influence to deflector plate in gas jet field of a Vehicle-mounted Vertically Thermal Launched missile as well as simulation study. The finite volume method, a fully structured grid, three-dimensional N-S equation is used for the numerical simulation of the process during the missile launching. The two main factors: temperature and forces on the launcher is the standard we test a launching system. The temperature on the position we test will rise with the decreasing length of the deflector. Especially, when the length is near to the potential core, the temperature changed greatly. Also, the angles of the deflector under the same length have less impacted on the temperature field. However, the force on the deflector would be change greater than the temperature with the change of angles
Study on the Microstructures and Properties of the Lead-Free Easy-Cutting Bial-Brass
Authors: Li Lei , Chen Yu Qi , Li Qiang , Huang Guo Jie
Published: February 2012

Traditional lead brass products pollute the environment and do harm to the human health. Fabrication of the new kind of the brass without lead is an urgent task. Bi-brass is the most popular lead-free easy-cutting brass. However, its mechanical and hot-working properties are not satisfied. In present paper, aluminum element was added into the Bi-brass alloy in order to improve the alloy’s mechanical and hot-working property. Experiment results showed that the aluminum can increase the surface tension of the Bi and change the existing morphology of Bi from film-like into particle-like. Therefore, the ingot’s hot-working property is excellent. Experiment results showed that even the extrusion ration reaches 256, the ingot still can be extruded into rod successfully. Experiment results also indicated that the homogenizing annealing treatment on the ingot and addition of the rare earth La did not improve the mechanical properties or the machinability.
Optimization of the Hydraulic Bellows Engine Parameters Used to Drive Irrigation Reel Hose Machine - IATF 300
Authors: Biolan Ilie , Sovaiala Gheorghe , Visan Alexandra Liana
Published: February 2012

This research was conducted during 1984-2009, on an irrigation reel hose machine - IATF-300 type. The paper presents the mathematical model that has been used to optimize hydraulic engine performance, its attempts where made taking in consideration the engine recommendations to test it to a load charge.
Distributed Task Allocation in Multi-Robot Systems Using Argumentation-Based Negotiation
Authors: Lolu Irina , Stanescu Aurelian , Moisescu Mihnea , Sacala Ioan Stefan
Published: February 2012

The continuous growing of application’s complexity and increased interest in automated negotiation brought recently researcher’s attention to persuasive negotiation (PN) and argumentation-based negotiation (ABN). The Market-based approach has gained popularity in the last decade due to its flexibility, speed and robustness. Contract Net protocol inspired algorithms have been proved suitable for allocating weakly coupled tasks in robot teams, but there are still some challenges when addressing complex application in uncertain environments. In this context the purpose of the paper is to present a method to allocate tasks in multi-robot systems through the use of augmentation- based negotiation.
Effect of Intermediate Location and Time-Varying End Mass on the Dynamic Response of a Flexible Robot Manipulator in Tracing Multi-Straight-Line Path
Authors: Kazemi Mojtaba , Ghayour Mostafa
Published: February 2012

This paper presents the effects of intermediate location and time-varying end mass on the dynamic response of flexible robot manipulator with rotating-prismatic joint in tracing multi-straight-line path. The tip end of the flexible robot manipulator traces a multi-straight-line path under the action of external driving torque and axial force. Flexible arm which consist of a rotating-prismatic joint, is assumed to be an Euler-Bernoulli beam carrying an end mass. The Lagrangian dynamics in conjunction with the assumed modes method is utilized in deriving the equations of motion. Effect of rotary inertia, axial shortening and gravitation has been considered in developing the dynamic model. Equations of motion are numerically solved by using the Runge-Kutta method. Numerical results of computer simulations for tip deflection are presented in graphical form. Physical trends of the obtained numerical results are discussed.
Measurements Methods of Industrial Robots Accuracy and Workspace Determination
Authors: Cimpoeru Ion
Published: February 2012

In this paper are presented the necessary concepts, several methodologies as well as algorithms for measuring the industrial robots precision experimental determination of workspace. Considering the fact that industrial robots precision it’s influenced by several factors I have studied various ways and measurement algorithms as well as the influence factors.
Research on Adsorption of H2S by Oil Shale Ash
Authors: Qin Hong , Tan Zhi Jia , Wang Qing
Published: February 2012

The ash of Huadian oil shale is made to remove H2S in this experiment. XRD and nitrogen adsorption experiments are used to analyze the physical and chemical properties of the ash, the results show that the ash of oil shale has many metal and nonmetal oxides, and also has much microporous and mesoporous, all above is helpful to remove H2S. The sample is modified by different ways to see the change of adsorption capacity. the sample which is modified by alkali and sprinkler is the best adsorbent, but the sample which is modified by microwave does not increase the removal ability obviously.
Methods to Improve Properties of Gate Dielectrics in Metal-Oxide-Semiconductor
Authors: Liu Chong , Fan Xiao Li
Published: February 2012

This essay aims to introduce development of gate dielectrics. In present-day society, Si-based MOS has met its physical limitation. Scientists are trying to find a better material to reduce the thickness and dimension of MOS devices. While substrate materials are required to have a higher mobility, gate dielectrics are expected to have high k, low Dit and low leakage current. I conclude dielectrics in both Si-based and Ge-based MOS devices and several measures to improve the properties of these gate dielectric materials. I also introduce studies on process in our group and some achievements we have got. Significantly, this essay points out the special interest in rare-earth oxides functioning as gate dielectrics in recent years and summarizes the advantages and problems should be resolved in future.
Structural Variation of Transition Metal - Fullerene Thin Films Modified by Thermal Annealing and Ion or Laser Beam Bombardment
Authors: Vacik Jiri , Lavrentev Vasyl , Horak Pavel , Fajgar R.
Published: February 2012

In this paper, we have inspected the structural morphology of novel composite materials - transition metal (TM) (Ni, Ti) / fullerene (C60) thin films, prepared at room temperature (RT) or 500°C, and modified by ion-irradiation and/or thermal annealing. The hybrid films were synthesized by alternative or simultaneous deposition of the immiscible TM and C60 phases. As deposited (at RT) the hybrid systems were thermodynamically unstable and the internal stress induced lengthy phase separation. Co-deposition at 500°C resulted in the formation of a large-scale pattern structure. By high temperature annealing of the multilayer’s a new morphology could be synthesized. In addition, high-fluence ion-irradiation induces C60 fragmentation that has a strong impact on the final shaping of the resulted morphology.
Brazing of Aluminum Tubes Using Induction Heating
Authors: Demianová Kristína , Behúlová Mária , Milan Ožvold , Turňa Milan , Sahul Miroslav
Published: February 2012

The contribution deals with the design of a progressive metallurgical joining of the solar collector parts by brazing. The main aim was to replace flame brazing by the more advantageous technology of brazing using high-frequency induction heating. New equipment and the induction coil of a suitable shape were designed for the joint manufacturing. Based on the numerical simulations of electromagnetic and temperature fields, the basic parameters of induction brazing were suggested in order to achieve the desired temperature distribution at the spot of the future joint. To check the quality of the brazed joints, a leak test, optical microscopy and EDX microanalysis were used to study the area of the brazed joints interface. Impact of brazing time and power supply on brazeability of Al alloys components by means of the AlSi12 braze were assessed.
Weighting of Goods by Means of DC Motor
Authors: Matousek Radomil , Namec Zdenek , Marada Tomas
Published: February 2012

The paper deals with the practical problem of the intelligent weighing and his real solution by means of unprecedented new progression. The project was concerned with handling and weighing goods with different weights of individual items. The basic part of the paper is a demonstration of automatic control of the intelligent process of weighing goods using mostly hardware and software resources by Phoenix Contact and standard DC motor platform. The basic idea of an intelligent weighing is based on the fact that the movement dynamics depends on the weight of the goods handled. In the process of movement control, detailed position and motor current values are measured to calculate the desired weight of the goods to be transported (handled).
A Density Functional Theory Study on the Ultra Long Single Walled Armchair (3, 3) (Bn)Xcy Nanotubes
Authors: Wang Yan Li , Su Ke He , Wang Xin
Published: February 2012

The single walled armchair (3,3) (BN)xCy nanotubes with different ratios of B, C and N atoms were studied with density functional theory of B3LYP/3-21G(d) combined with the periodic boundary conditions in simulating the ultra long tube model. Different types of twelve models were examined and the diameter, energy, energy gaps and the band structures were obtained. The energy gaps were within 0.203eV to 2.620eV showing semiconductor conductivity. Results show that the energy gap and the band structure depend on both the atom ratio and arrangement.
Preparation of Nanosized Molecularly Imprinted Polymer Spheres for Atrazine
Authors: Xie Rong , Gui Wen Jun , Zhu Guo Nian
Published: February 2012

A novel nanosized molecularly imprinted polymer spheres for atrazine was synthesized in present assay, as an alternative to the biological antibodies. Both precipitation polymerization and bulk polymerization were performed. Various combinations of template, functional monomer, and cross-linking monomer and porogenic diluents were carried out to optimize the best one. The nanosized MIPs exhibit larger surface area and better binding capacity than traditional polymers, the best binding capacity and imprinted factor for atrazine were 95.75% and 1.83 respectively.
Study of Polarization and Relaxation on Pb(Zr,Ti)O3 Thin Films by Scanning Probe Microscopy
Authors: Shen Jian , Zhang Dainan
Published: February 2012

Polycrystalline Pb(Zr0.55T0.45)O3thin film was deposited on Pt/Ti/SiO2Si(100) by radio-frequency-magnetron sputtering method, the writing of charge bits and the polarization relaxation phenomena on the surface of PZT thin film was studied by Kelvin probe force microscopy and Piezoresponse force microscopy, respectively. It is found that the surface potential of the negative charge bits are higher than those of the corresponding positive ones, and the charge accumulates remarkably in high vacuum but relax more quickly. The domain images (contrast) reveal that the polarization magnitude is determined by the orientation of each grain, which is proved by the Ref 14. Taking the polarized area as whole, the relaxation of polarization magnitude (contrast) show that the polarized state in some grain can maintain at leas¬t 105s, but in other grain, the polarization disappear relatively quickly.
Hydrothermal Synthesis of CeO2 Nanocrystals Using Oleate-Modified Precipitation Method
Authors: Kobayashi Katsutoshi , Haneda Masaaki , Ozawa Masakuni
Published: February 2012

Monodispersed ceria nanocrystals have been synthesized by an oleate-modified precipitation method combined with a hydrothermal treatment at 200°C. TEM observation indicated that ceria nanoparticles with low-crystallinity were produced by synthesis at room temperature, which were crystallized by subsequent heat treatment to form nanocrystals. Produced ceria nanocrystals were well dispersed in a nonpolar solvent and were hardly agglomerated. TEM observation and Raman spectroscopy clarified that the size of ceria nanocrystals was in the range of 2-7 nm. Interparticle distance of cerium nanocrystals two-dimensionally aligned was in the range of 1.5-4 nm, which corresponds to the exclusive distance of oleic chains. Oleate-modified ceria nanocrystals exhibited strong fluorescence by green-laser excitation. Fluorescent behavior of ceria nanocrystals indicated that oleate detachment from the ceria surface and particle growth of ceria nanocrystals could be induced by laser irradiation.
Application of the Measurement and Control Network on Rewinder
Authors: Liu Peng , Liu Xing Ping , Wang Bin Peng
Published: February 2012

As the improving of rewinding machine production process and the speed of rewinding machine,the higher request of rewinding machine control systemis is put forward.So the control system is established to process,analysis and share various data.According to the request, a set of complete rewinding machine measurement and control network based on Field-bus is introduced in the paper.It is testified by experiment that this system can process and share the various data
Automatised Line Used for the Assembly/Test Subsystem-Carcass
Authors: Telea Dorin , Barbu Stefan
Published: February 2012

This paper presents the main CAD –computer aided design – elements of an automatised assembly/test line, destined for work posts for the assembly/testing of the subsystem-carcass, in agreement with Compa SA Sibiu. The carcass is part of the turbo-compressor assembly (compressor + turbine) of a testing equipment. The analyzed line contains 7 work posts, with direct application to the assembly/test disc type parts but it can be generalized to the serving, to the purpose of testing, of many such posts in a automatised assembly line and carcass checking. Because carcass with lacking or inconsistent processing can end up on the assembly line, it has been decided to design and produce an automated line, so these things should not happen, because these part son an automated assembly line can cause the stopping of automated flux until the faulty part is being replaced.
Study on the Safety Assessment of the Mobile Scaffolding System Metal Structure Based on the Onsite Inspection
Authors: Zhang Zhi Bin
Published: February 2012

This article based on the analysis of the characteristics and the content of the Mobile Scaffolding System (MSS) safety assessment, and according to the on-site inspection of the two MSSs, constructed the MSS metal structure safety assessment index system, and applied the expert scoring method to give the importance degree of every index, finally put forward the fuzzy comprehensive evaluation method for the evaluation criteria.
Synthesis and Characterization of CeO2-ZrO2-Al2O3 with High Thermal Stability and Oxygen Storage Capacity from Pseudoboehmite Precursor
Authors: Zhang Dong
Published: February 2012

The surface and structural properties, thermal stability and oxygen storage capability are inverstigated in ceria-zirconia-alumina oxide with deposition coprecipitation method using the Pseudoboehmite precursor. X-ray diffraction (XRD), Brunauer-Emmet Teller method (BET), Transmission electron microscopy (TEM) and oxygen pulsing technique are used to character the prepared materials. The prepared ceria-zirconia-alumina oxides are highly dispersed composite solid solution. After calcination at 650 °C and 1000 °C respectively, these compounds can still keep the structural and textural stability and hold excellent oxygen storage capability.
Finite Element Analysis and Design Exploration of a Bolted Joint
Authors: Piscan Iuliana , Predincea Nicolae , Pop Nicolae
Published: February 2012

The present study demonstrates the use of optimization technology in improving the bolted joint design. Design exploration from ANSYS Workbench is used in the study. The objective of the study was to minimize the bolted joint deformation in order to optimize the joint. Variations of the parameters such as bolt pretension force, friction coefficient and pressure were studied. The optimization study provided response charts of the different design variables on the output. Sensitivity analysis of the input variables helped in identifying the importance of each design variable and their respective effects on the output. Finally the different design points were rated based on a goal-driven optimization study and the best design is chosen. Single Graphical User Interface allowed quick learning and ease-of-use.
Fuzzy Thrust Staging Kinematics for the NERVA Strap-On Boosters
Authors: Rugescu Radu Dan , Staicu Stefan , Mahmoudian Seyed Mohamadreza
Published: February 2012

NERVA small space launcher under development in Romania by Politehnica University is based on the solution of hard take-off with three strep-on SRM boosters. Due to the very high thrust enhancement a lift-off loading of more than 40 g-s appears, which is quite challenging. The main challenge is connected with the possible uneven thrust and burn duration of the three SRE-s of the first stage, which we call fuzzy thrust. Experimental data show variations of up to 0.5 seconds in the duration of the powered phase of SRE-s, from a total of 3.0 seconds of a mean burn. Yet undetermined variations in the total ignition delay between individual motors are a stronger concern. While for the unique booster of the standard SA-2 vehicle the ignition delay has no impact, when those engines are forced to work in parallel the individual differences become catastrophic. Severe imbalance between the two lateral engines may occur, ending in a potentially severe damage of the launching rail, possible loss of flight stability along the boost phase and damage of the second stage structure. The problems regarding the efficiency of the propulsion system that accompany this project are considered and solutions are proposed for the high thrust augmentation of the booster stage. Cryogenic vs storable propellants are studied for thrust augmentation of the boosters.