bluuebunny/crossref_metadata_2025 huggingface dataset:
Proposal of Mashup Framework for End Users
Authors: Koita Takahiro , Nomura Sotaro
Published: July 2013

This paper proposes a new mashup framework for end users and discusses the usability of the proposed framework. Recently, a wide variety of requirements for web services has arisen because more users are using web services in their daily lives. However, a single web service cannot satisfy all requirements due to the variety of those requirements. To satisfy the requirements, it is important to have web service mashups which coordinate a number of web services to match the requirements. A mashup framework is a software environment that makes it easy for developers to make mashups. The challenge of this study is to develop a new mashup framework for end users with a new mashup model and modules. The model and the modules are implemented in the proposed framework.
Research and Development of the Computer Aided RCM Analysis System Database
Authors: Liu Zhong Peng , Cheng Zhong Hua , Li Si
Published: July 2013

From the RCM analysis demand of equipment, the function and constitution of the computer aided RCM analysis system are discussed in this paper. The function and composition of the database system are expounded. Meanwhile, the basic train of thought RCM analysis database system is put forward.
Multiple Crack Growth and Coalescence in Meshfree Methods with Adistance Function-Based Enriched Kernel
Authors: Barbier E. , Petrinic Nik
Published: July 2013

Distance fields are functions defining the minimum distance between any generic point inspace and the boundaries of an object. This paper shows some important properties of these fields andtheir derivatives. In fact, for polygonal lines, the derivatives of distance fields are discontinuous overthe finite length of the segment, but continuous all around the end-points. An immediate consequenceis their application as intrinsic enrichment of weight functions in meshless methods, for the treatmentof multiple arbitrary cracks. By introducing such explicitly known function for the distance fields,discontinuities can be easily incorporated in the kernel in a simple, multiplicative manner. The result-ing method allows a more straightforward implementation and simulation of the presence of multiplecracks in a meshless framework without using any of the existing algorithms such as visibility, trans-parency and diffraction. Furthermore, one of the main advantages of this approach is the automaticcoalescence of multiple interacting cracks, i.e. no particular enrichment functions are necessary at thejunction points.
Liquid-State Synthesis and Properties of Fluorescent Conducting Polymers: α, βi-SiW11AlIII/Polyaniline
Authors: Yang Wan Li , Wang Qing Wen , Ma Rong Hua
Published: July 2013

Four polyaniline hybrid materials were prepared by liquid-state synthesis method in the presence of dopant which synthesized by transition metal mono-substituted Keggin structure silicotungstate anions α, βi-[SiW11Al (H2O)O39]4-.The polyaniline hybrid materials were characterized by elemental analysis, IR spectroscopy, fluorescence spectroscopy, scanning electeon microscopy (SEM) and thermo gravimetric analysis, the properties of which such as thermal stability and conducting behavior were studied. It proved that the average diameter was 100nm, the conductivity was 9×10-2s·cm-1 and the flourescence property was better.
Research on the Preparation of the Low Density Material with High Volume Filling Rate of Phenolic Hollow Microsphere
Authors: He Xue Tao , Shao Jian Bo , An Ying , Ma Kun , Wang Jian Qiang , Yang Wei Min
Published: July 2013

In this paper, an experimental mixing equipment has been developed for producing low density material with a high volume filling rate of phenolic hollow microsphere. The experiments with the equipment aim to explore the feasibility of this equipment for industrial production and to optimize the process. Experiments have been made to evaluate the influence of the filling ratio and the mixing rotor movement on the mixing effect. The results show that when the volume filling ratio of the material to the mixing barrel is about 40% the mixing effect is the best. But with mixing time increasing, the broken ratio of hollow microsphere will increase too. To solve this problem, some changes on the rotor movement have been made. The results show that the broken ratio increasing rate becomes lower and the density becomes more uniform. These indicate that the broken ratio can be well controlled by a suitable production process.
Experimental Study on Rubber Open Mill Mixing Process Parameters
Authors: Zeng Xian Kui , An Shuai , Wang Dong , Song Guo Zong , Ren Na
Published: July 2013

Experimental research on the relationship between rubber open mill mixing process parameters of roller pitch, roller speed and roller speed ratio changes and mix quality. The results show that the process parameters changes in open mill mixing process have significant effects on mixing quality and efficiency. And get the best process parameters optimization in open mill mixing process: the best changes trend of roller pitch, roller speed and roller speed ratio are from small to big, from small to big and from big to small.
Study on Cross Linking Eliminating and Regeneration Mechanism of Scrap Rubber
Authors: Guo Lei , Wang Chuan Sheng , Shan Ti Kun , Tao Yi Wei
Published: July 2013

The regeneration technology of scrap rubber has been studied for many years, and now it is widely used. But the regeneration mechanism is still not being reached. So far, there is no theory for regeneration mechanism of scrap rubber. Under this circumstance, this paper presents a deeply reached study around this issue.
Experimental Study on the Rubber Continuous Plasticator
Authors: Fu Ping , Zhang Hong Lei , Wang Chuan Sheng
Published: July 2013

Two rotor configurations were designed for the continuous plasticator in this paper. The rotor configuration, rotor speed and machine barrel temperature were set as the variable parameters in this contrast experiment. What’s more, the experimental investigation showed that, the three factors had effects on the plastication performance. When the temperature of machine barrels and extrusion dies reached and the rotor speed was at , the plastication performance of two rotor configurations was relatively better. And the rotor configuration II was better than I by synthesizing all kinds of factors.
Research on the Optimal Rotor Speed of the Mixing-Molding Integrative Machine
Authors: Li Li , Sun Shu Hua , Wang Zhen Lu
Published: July 2013

This article is targeted at different rotor configurations, using of laboratory experimental platform of existing small synchronous rotor of internal mixer, under consistent conditions of cooling water temperature, floating weight pressure, filling coefficient, along with the change of rotor speed, experimental study on five different rotor configurations. Through comparison of the experimental results, choose the best rotor speed, and for further experimental research to provide the optimal parameter selection basis, to ensure that the mixing performance of the mixing-molding integrative machine.
Simulation Study for the Effects of Clearance Volume on Full Metal Single Screw Pump Performance
Authors: Wu Jun Fei , Meng Fan Guo , Zhang Xu Ping , Yu Ying
Published: July 2013

The stators and rotors of full metal screw pump take way of clearance fit, so the clearance value will directly affect the pump lifting performance and efficiency. Firstly using the finite volume method to establish a full-metal single screw pump 3D model, secondly using FLUENT software to calculate outlet pressure changes with different series of clearance value between the stator and the rotor of the pump in condition of the same inlet pressure .lastly Drawing outlet pressure change curves to evaluate the concrete effect of clearance volume on the performance of the pump. The results indicate that the pump outlet pressure increased first and then decreased with increasing clearance value and that pump has good lifting oil capacity with clearance value which is less than 0.5mm.
Automatic Generation of the Word in Tire Mold Side Plate Based on Font Vectorization
Authors: Hu Hai Ming , Li Hui , Yin De Bao
Published: July 2013

This paper introduces vectorization technology fromTrueType font for the text on the sidewall plate of the tire mold. TrueTypefont processing technology is the extraction of Windows functions and datatypes of the font outline. Call the API function to process the text in orderto achieve the CNC Machining of the text. It completes the tire mold word-processingsoftware on this basis. The software enables a variety of functions includingtext layout, font zoom, font spacing adjustment, font choice. It also providesa rapid tool for the quickly arranged and CNC machining of the text on thesidewall plate of the tire mold.
Fatigue Analysis of Linear Vibrating Screen with Different Surface Roughness
Authors: Zhang Ze Rong , Xu Jun
Published: July 2013

The multiaxial stress is acted on the sidewall and beams of the large linear vibrating screen. So the critical plane method is used for calculating the fatigue lives of the large linear vibrating screen. The logarithm fatigue lives nephogram is drawn and the logarithm fatigue lives of large linear vibrating screen are analyzed. The local logarithm fatigue lives for different surface roughness of the vibrating screen is calculated and the results shows that the fatigue lives decrease quickly when the surface roughness increases.
Research on the Vector Measure Method of Coordinate Measuring Machine
Authors: Han Zhao Lin , Yuan Mao Xing
Published: July 2013

When we use Coordinate Measuring Machine to measure some points of the workpieces, the wrong measuring method will get the poor repeatability and poor reproducibility of measurement results. Now the vector measure of the CMM is a more convenient way. The main principles are analyzed in this paper, and a workpiece is measured for example.
Detection and Location of Underwater Pipeline Based on Mathematical Morphology for an AUV
Authors: Wang Xian Lun , Li Li , Cui Yu Xia
Published: July 2013

Underwater pipelines of oil and gas need periodic inspection to prevent damage due to the biological activity of water, turbulent current and tidal abrasion. Currently, vision-based autonomous underwater vehicle plays an important role in this field. A system has been designed to help an autonomous vehicle in sea-bottom survey operation. Image understanding and object recognition directly affect the accuracy of inspection. An image smoothing method based on mathematical morphology is proposed. The disturbances on acquired images caused by the motion are partially removed. A series of algorithms about image preprocessing, segmentation and recognition are proposed to access pipeline contours from the top-view images effectively. Navigation data based on Hough transformation is presented after the analysis of contours. Finally, the processing effect on a pipeline image demonstrates the effectiveness of the system.
Springback of TRIP Steels under Varying Blank Holder Force
Authors: Shan Ti Kun , Liu Li
Published: July 2013

The method using variable blank holding force to control springback in drawing of TRIP sheet steel is discussed. Numerical simulations considering the variation of Youngs modulus of TRIP steels can improve springback simulation accuracy. Many experiments are use to test and the accuracy of the springback simulation for an U-channel part forming under variable blank holding force. The results shows that the strategy of variable blank holding force is an effective measure for the springback control in TRIP sheet metal forming processes and the dimensional accuracy of sheet metal parts can be increased by the optimization of variable blank holding forces
The no Alarm Faults Examples for Maintenance on a Combining CNC Machine Tool of Turning and Grinding
Authors: Guan Shang Jun , Yang Ke
Published: July 2013

Our self-developed a combining CNC machine tool of turning and grinding uses modular structure，easy to operate and easy to service，so it has been widely applied. For the most part, there will be alarms when the combining CNC machine tool of turning and grinding has faults, but sometimes there may be no alarm. This paper briefly presents the no alarm faults examples and its resolutions for a combining CNC (Computer Numerical Control) machine tool of turning and grinding, which provides an important basis for technicians to operate and maintain the Combining CNC machine tool of turning and grinding.
Design of Open-Architecture Gantry Milling NC System Based on Motion Control Card
Authors: Chen Dong
Published: July 2013

The open-architecture control system is designed to realize the accurate motion control of gantry milling machine in this article. The hardware construction of control system adopts industry PC + Clipper motion control card architecture to achieve the opening and modularization. The Full coordination method is selected by assigning two motors of the gantry system to the same axis in the same coordinate system. The function modules of control software are demonstrated. It is programmed based on Visual c++ and Pcomm32 pro DLL library. The design of the gantry milling control system can realize the opening of architecture, and more accurate, smooth motion control of 4 axes.
Design of Human Tracking Algorithm Based on Improved Camshift
Authors: Huang Yi Hu , Ma Ji Xiang , Han Xiao Dong , Hu Ning , Jia Xi Mei
Published: July 2013

Considering the problem of added background interference when initial target region is chose in Camshift tracking algorithm. This paper proposes a human tracking algorithm based on improved Camshift. The algorithm uses weight to determine the type of pixels in the back-projection, and then convert the back-projection into binary image, so as to improve the input accuracy of Camshift processing function. According to the human body size information, the algorithm appropriately improves the ratio of major axis and minor axis of search window, to optimize the output size of Camshift processing function. The contrast experiment proves the algorithm obviously improve accuracy and robustness of tracking effect.
Numerical Simulation on Dispersive Mixing of Solid Powders/Polymer Matrix in Two-Rotor Mixer
Authors: An Ying , Ding Yu Mei , Wang Jian Qiang , Ma Kun , Yang Wei Min
Published: July 2013

In this paper, employing the mixing theory of polymer and the numerical simulation of polymer processing, numerical simulation model for dispersive mixing of solid powders in polymer matrix is studied, and a multi factor accumulative size distribution function is established. Based on this, the dispersive mixing processes of black carbon/natural rubber are studied using three-dimension dynamic numerical simulation, and the influences of operating conditions on the dispersive mixing of black carbon are analyzed. The simulation results show that the final size of solid powder aggregates is depended on the rotational speed of rotors. When the maximum shear stress of polymer flow field is sufficient to overcome the cohesive force of solid powder aggregates, the size of aggregates distribution will be related with mixing time.
Experimental Research on the Mechanical Properties of Rubbers under Different Curing Pressures
Authors: Li Tao , Yang Guang Zhi , Zhang Wei , Li Qing Ling
Published: July 2013

The influence of curing pressure on rubbers’ mechanical properties was researched with experiment. The results show that the curing pressure increased appropriately can improve the curing rate and shorten the curing time. Meanwhile the curing pressure increased also can enhance the tensile strength and 300% stress at definite elongation of the rubber cured but reduce the elongation at break, tension set, tearing strength and the abrasion property of the tread rubber. The properties of each rubber are different from each other with the same curing pressure.
Generalized Thermal Design Model for Comb-Capacitor MEMS Devices Fabricated by Bonding-DRIE Process: A Preliminary Framework
Authors: Sun Han , Yang Fang , Wang Wei , Zhang Da Cheng
Published: July 2013

Bonding-deep reaction ion etching (DRIE) is a standard microelectromechanical system (MEMS) fabrication technique, especially for widely-applied comb-capacitor microdevices. Being the key structure in the comb-capacitor devices, long and narrow suspended beams suffer a serious heat transfer problem during their releasing in the fabrication because of the high heat flux input and the large thermal resistance. Temperature increment of the micro beam in the DRIE releasing, especially in the unavoidable over etching stage, may cause serious problem, even lead to a failed etch. This work introduced a generalized thermal design model to estimate the possible temperature increment of microstructure in DRIE. The preliminary results indicated that this model was able to capture the basic trend of temperature variation with the geometrical parameters in a comb-capacitor MEMS device during its DRIE releasing.
Single Mask Selective Release Process for Complex SOI MEMS Device
Authors: Xie Jian Bing , Hao Yong Cun , Chang Hong Long , Yuan Wei Zheng
Published: July 2013

We present a single mask selective release process for complex SOI MEMS device. Comparing to the one-step dry release process, there are two improvements, the first one is to ensure that the bottom of the suspension beams will not be notching, and have sufficient strength and rigidity, the second one is to ensure that the released structures will not be damaged during wafer dicing. According to the proposed design rules, in the dry release step, most of the device area is released, except the boundaries of the proof mass and the suspension beams. Then, in the wet release step, all the structures will be released, and also increased the gap below the structure. So the suspension beams is protect enabled that the device has sufficient rigidity and not easy to break. To verify this method, a micromachined gyroscope is fabricated and test.
Analysis on the Sticking Failure of Micro-Comb Driving Structure
Authors: Liu Hai Peng , Zhang Zhen Quan , Gao Shi Qiao , Jin Lei
Published: July 2013

As an important part of MEMS, the micro-comb electrostatic driving structure is the main source of mechanical movement in many MEMS devices. Its reliability will directly affect the using performance of the MEMS devices. The electrostatic driving system of micro-comb capacitive micro-machined gyroscope can be equivalent to a second order system. If the applied voltage is less than the pull-in voltage, the movable micro-comb will maintain a steady state. Otherwise, the micro-combs will stick together because the applied voltage is greater than the calculated pull-in voltage. If the distance between micro-combs is too narrow, the role of these micro forces will be very significant. The pull-in phenomenon occurring in the process that the micro-machined gyroscope is applied on a phase step input voltage will lead to the very narrow comb spacing. As a result that the role of micro-forces such as the capillary force, Van der Waals force and Casimir force will become very significant, and the micro-combs will stick together permanently.
Design of MEMS Wireless Air-Mouse System Based on MEMS Technology
Authors: Zhou Huo , Mo Bing , Huang Rui Ming , Ling Chao Dong , Huang Rong Hai
Published: July 2013

In this paper, we study the MEMS wireless air-mouse system(MWAMS), which based on three-axis gyroscope、three-axis accelerometer、magnetometer and wireless RF technology. It makes use of MEMS motion sensing technology、information fusion algorithm and DCM complementary filter algorithm to sensing air-mouse's motion. This paper presents a new multi-sensor optimal information fusion and mapping algorithm. Compared to the traditional algorithm, this new algorithm based on MEMS technology not only has higher performance-higher location accuracy and better smoothness, but also has lower power consumption.
MD Simulation of MEMS “Stiction” and “Snap-Back” Phenomena
Authors: Tian Wen Chao , Zhao Lai Qiang
Published: July 2013

Aiming to explain phenomena of “stiction” and “snap-back”, a ball-surface adhesion is simulated with molecular dynamics (MD) based on multi-body EAM potential function. Surface atoms “summon up” and migrate, which lead to the phenomenon of “stiction”. The migration velocity of interface atom is not consistent. Some atoms migrate too fast, which lead to the phenomenon of “snap-back”. The “Snap-back” phenomenon appears twice during the adhesion process. A “neck-separation” phenomenon is found. The adhesive force in the separation process obviously lagged the adhesive force in the contact process, which shows there is energy loss during the adhesion process. The curve of adhesion deformation is simulated finally, and compared with relevant results.
The Oxygen Plasma Dry Release Process of the Membrane Bridge of RF MEMS Switches
Authors: Jiang Li Li , Jia Shi Xing , Zhu J.
Published: July 2013

In this paper the oxygen plasma dry release process for membrane-bridge RF MEMS switches is studied and several methods are used to improve the dry release process. The residual PR (Photoresist) on the device substrate after different process time are observed and measured in this paper. The measured data shows that the residual PR exponentially reduces with etch time. It is found that the residual PR on the bottom surface of the membrane bridge is more than that on the substrate. The completely released RF MEMS switch using oxygen plasma dry etch process is obtained.
A Novel Analytical Method for Designing Microelectromechanical Filters
Authors: Zhao Hui , Luo Wei , Yang Jin Ling , Yang Fu Hua
Published: July 2013

This work presents a novel analytical model for designing resonator-based MEMS filters, which eliminate the computing error caused by material parameters and generates more reliable theoretical model. This model is comfired by a composite-array filter in the work. Furthermore, this model can be applied for MEMS filters formed by any type of resonators, the geometries of the mechanical coupling beams are determined with high precision.
Effects of Plasma Nitriding and TiN Coating Duplex Treatment on Tribological and Electrochemical Properties of Cast Pure Titanium
Authors: Tong Yu , Guo Tian Wen , Wang Jing , Liang Hai Feng , Mi Qian
Published: July 2013

The effects of different surface treatments on tribological and electrochemical properties of cast pure titanium were investigated. In this study two different surface treatments were performed which were TiN film deposition by arc ion plating, duplex treatment of plasma nitriding and TiN film deposition. Both surface treatment improved tribological and corrosion behavior of cast titanium. The duplex treated specimens exhibited higher surface hardness, better wear and corrosion resistance compared with TiN film deposited ones. All these results indicate that plasma nitriding and TiN film deposition duplex treatment can improve surface characteristics of cast titanium significantly.
Research on the PDMS Surface Modification Technique
Authors: Tian Li , Wu Lei , Wang Wei , Liu Xiao Wei
Published: July 2013

UV radiation, oxygen plasma treatment and dynamical coating technique were the three main modification techniques to be widely applied in the surface modification of polymer materials. This paper presented the experiment results of PDMS surface modification with these three techniques. The contact angle was measured to test the modification effect, also the further verification testing of aging property after a long time storage were carried out. Of all the testing results, the dynamical coating technique, 10 layers 0.02% PDDA and PSS (V/V) alternatively adhesion on the PDMS surface, made the contact angle lowed to the 21°, and even after 15 days, it still kept as the 61°and exhibited the better hydrophilic character.
Morphology Controlled Nanostructure of Zinc Porphyrin
Authors: Li Jun Jie , Hou Chang Jun , Li Zhi Fei , Fa Huan Bao , Yang Mei , Huo Dan Qun , Zhang Liang
Published: July 2013

We have shown that various Zinc porphyrin-based nanostructures can be easily synthesized by a surfactant-assisted self-assembly method, where nonionic, anionic and cationic surfactants are employed. It was found that tuning the type of surfactant offered an alternative to promote the formation of Zinc porphyrin nanostructure with different morphologies in aqueous solutions. As-prepared nano-scale self-assemblies, including disc-shaped, ellipsoid, square and quadrangular pyramidal nanoparticles, were investigated in solution via UV/vis, fluorescence spectroscopy and SEM microscopy. The different UV/vis as well as fluorescent spectra between nano-porphyrin and its monomer further conformed that the nano-crystallization of porphyrin would result in novel optical properties differing from the single subunits.
Photocatalytic Degradation of Organic Pollutants at Solution Bulk with Pigment/TiO2 Nanocomposite
Authors: Shangand Xi Li , Zhang Tian Yong , Li Chang Hai , Li Bin , Wang Xiao
Published: July 2013

In this paper, two newly explored TiO2 photocatalyst sensitized with commercial stable pigment (BYH3G and PR254) were prepared and characterized by FT–IR, UV–Vis, XRD and N2 adsorption-desorption isotherms. The adsorption capacities and the photocatalytic activities of as-prepared photocatalysts were evaluated by photocatalytic degradation of Methyl Orange and Rhodamine B under visible light irradiation. The as-prepared photocatalysts displayed high visible light photocatalytic activity than pure TiO2 under the same conditions. The photocatalytic activity can be reproduced commendably demonstrates that the as-prepared photocatalysts are stable and renewable, which are potentially important properties in the application of industrial wastewater treatment.
A Control Algorithm for Near-Infrared Spectra Detection System Based on Grating Light Modulators
Authors: Wei Wei , Chen Wei Min , Wang Ning , Qin Yi
Published: July 2013

In this paper, a novel control algorithm for near-infrared spectra detection system based on grating light modulators is proposed. Firstly, the principle of this novel control algorithm is analyzed theoretically, and the encoding and decoding process of two scanning modes based on the control algorithm are obtained. Secondly, the numerical simulation is carried out to evaluate the effect of this control algorithm on the signal-to-noise ratio (SNR) of the spectra detection system. The difference between the SNR of the system under different scanning modes is acquired. When the number of pixels M in a unit becomes larger, the stage number of driven voltages is smaller. In the end, related experiments have been set up, and the feasibility of the control algorithm is validated. By using the novel control algorithm, the detected spectrum of 1340nm narrow band filter could be reconstructed well and the deviations of the peak wavelengths under both scanning modes based on this algorithm are less than 1nm. Furthermore, the novel Hadamard transforms scanning mode based on this control algorithm could not only decrease the complexity of the control circuit but also increase the SNR of the spectra detection system.
A Low Noise Operational Amplifier Design Using Chopper Stability
Authors: Liu Xiao Wei , Liu Liang , Yang Jian , Chen Song , Chen Wei Ping
Published: July 2013

Noise has become a significant bottleneck limiting the performance of the op amp, and chopper stabilization technology [1] is commonly used to reduce the noise of the op amp. The chopper stabilization technology can significantly reduce the low-frequency 1/f noise of op amp, then reducing the total low-frequency noise of op amp. In this paper, we designed a chopper-stabilized low-noise op amp, and used Cadence software for simulation and debugging.
Characteristics of Pore-Throat Structure and Mass Transport in Ultra-Low Permeability Reservoir
Authors: Xiao Qian Hua , Yang Zheng Ming , Wang Xue Wu
Published: July 2013

Low permeability reservoir is one of the most important petroleum reserve types in China. Therefore, some basic scientific problems about low permeability reservoir such as pore-throat size distribution, principle of porous flow should be deeply studied. Pore-throat size distribution, based on 69 cores from Changqing and Daqing oilfield of China, has been measured by comprehensive using Constant-Rate Mercury Injection and Nuclear Magnetic Resonance. It has been found that the Nano-pore-throat takes more than 60 percent of the total pore-throat of the low permeability reservoir and it is the key factor affecting the flow capacity when the permeability is less than 0.5×10-3μm2. The nano-pore-throat takes less than 40 percent of the total pore-throat and micron-pore-throat takes more than 45 percent when the permeability is larger than 5×10-3μm2. And Micron-pore-throat is the key factor affecting the flow capacity of low permeability reservoir. But when the reservoir permeability is between 0.5×10-3μm2 and 5×10-3μm2, its flow capacity is determined by the sub-micron-pore-throat and the amount of micron-pore-throat. Additionally, the key forces in micro-, sub-micro- and nanoscale pore-throat has been got by analyzing. The electrokinetic coupling matrix of mass transport has been gotten by analyzing the characteristics of the mass transport in small tube at different Debye ratio and pore-throat size distribution of ultra-low permeability.
Effects of Different Relevant Layers on Magnetic Properties of Bottom Synthetic IrMn Spin Valves
Authors: Bai Ru , Qian Zheng Hong , Sun Yu Cheng , Li Jian Ping , Zhu Hua Chen , Li Ling Wei , Li Yuan , Huo De Xuan , Zhan Hong Liang
Published: July 2013

The effects of different relevant layers, especially the insertion layers (which are between Ta buffer layer and IrMn pinning layer) and free layers, on the magnetic properties of IrMn bottom-pinning spin valves are investigated. Spin valve with a NiFe insertion layer exhibits a higher GMR ratio of ~ 6.0% than that of 2.0% for the spin valve with a Cu insertion layer due to a better pinning strength. The spin valves with a CoFe/NiFe composite free layer have relatively better magnetic properties: a higher GMR ratio compared with the spin valve with a single NiFe free layer and a lower free layer coercivity compared with the spin valve with a single CoFe layer.
Low Stress MEMS Delay Mechanism
Authors: Li Guo Zhong , Shi Geng Chen , Sui Li
Published: July 2013

For the existing symmetry Z-tooth MEMS delay mechanisms can not play sports in place under the influence of centrifugal force, this paper presents an asymmetric Z-tooth delay mechanism which can works reliably by weak environmental forces. Working principle and the stress condition of the mechanism are analyzed. Based on the dynamic model, this paper makes a computational analysis and simulation about the kinetic characteristics of the asymmetric Z-tooth delay mechanism, and the results show that the improved mechanism can works reliably and meets the requirements.
Fabrication of Low Stress PECVD-SiNx Film in High Frequency Mode
Authors: Shang Zheng Guo , Li Dong Ling , Wen Zhi Yu
Published: July 2013

A new fabrication method to produce low residual stress PECVD SiNx layers at high frequency (13.56 MHz) was developed. High frequency up to 60W is employed in this new method to fabricate low stress SiNx. By adjusting the composition of reactant gases, process vacuum and the chamber temperature, the residual stress can be lower to-0.28 MPa, and high deposition rate up to 240 nm/min can be achieved. In addition, this paper investigated the influence of other important parameters on the results, such as pressure, power and gases flow rates. Moreover, by using the optimal process, the refractive index is ranged from 1.98 to 2.20, and the uniformity of run to run wafers is about ±3% for 4 inch wafers. Finally, a typical FBAR (film bulk acoustic wave resonator) structure using these low stress PECVD SiNx layers as solid layer and mask indicated that these layers are compatible in IC technology and suitable for using in fabricating MEMS(microelectromechanical systems) devices.
Optical Current Sensor Technology in Power System
Authors: Wang Li Hui , Sun Jian , Ji Jian Fei
Published: July 2013

With power voltage and capacity improved greatly, power transmission system put a higher demand on reliability and safe operation of electrical equipments. Electromagnetic sensors and other conventional detection equipment can no longer meet the needs of the power system, and new sensing measurement techniques led to optical current and voltage sensing technology. As their unique advantages, optical current sensing technology is get in-depth study and attention, and gradually used in power system engineering applications. Combined with domestic and foreign research progress of optical current sensor, we analyzed the basic principles of the photoelectric sensing technology and problems faced in power system applications and key technologies. Focused on sensing characteristic differences of photoelectric sensors and electromagnetic sensor, we analyzed the effects of photoelectric sensor on protection, monitoring and control, measurement systems in data processing and data transmission, and study the corresponding key technology. Combined with the development of modern power system, we prospect optical current sensor sensing technology opportunities and challenges in smart grid.
Capillary Condensation Adhesion Phenomena and Analysis of the Micromechanical Gyroscope
Authors: He Yun Li , Liu Hai Peng , Gao Shi Qiao , Wang Cai Feng
Published: July 2013

In MEMS, the size of micro-structure is usually in the micron and even nanoscale. It's easier to form capillary phenomenon than the macroscopic system. In view of this phenomenon, this article is based on the micro-mechanical gyroscope as the research object, to analyze the occurrence of capillary condensation of adhesion phenomenon. Firstly, we derive the Kelvin equation for capillary condensation, and then combination of the Kelvin equation introduce the capillary condensation of the adhesion phenomenon; Secondly, it analyzes the dynamics characteristics of its structure existing the liquid bridge, and analyzes the causes of the liquid bridge; Finally, it analyzes the capillary adhesion phenomena on the performance of the micro-mechanical gyroscope,as well as how to avoid the generation of capillary condensation adhesion.
A Sub 0.8 Degree per Hour Mode-Matching MEMS Vibratory Gyroscope with Closed Loop Control for the Sense Mode
Authors: He Chun Hua , Zhao Qian Cheng , Liu Da Chuan , Yang Zhen Chuan , Yan Gui Zhen
Published: July 2013

A detailed analysis about the nonlinearity of a mode-matching MEMS vibratory gyroscope is presented in this paper, then closed loop control for the sense mode is adopted to improved the performances. Experimental results figure out that the mode-matching gyroscope with closed loop controlled sense mode achieves a scale factor of 65mV/deg/s with nonlinearity of 0.05% and asymmetry of 0.1%, and a bias instability of 0.77deg/h, while they are 60mV/deg/s, 1%, 4.6% and 9.8deg/h in the open loop controlled sense mode system, respectively. These performances can be improved by more than one order of magnitude in the closed loop control system.
Edge Effect on Viscous Drag of the Rotor in Liquid Floating Rotational Micro-Gyroscope
Authors: Zhang Hai Feng , Zhang Xiao Shu , Liu Xiao Wei , Liang Yin Chun , Weng Rui
Published: July 2013

A liquid floating rotational micro-gyroscope is proposed in this paper, whose stability is improved by liquid suspension. High rotor velocity is needed to improve its sensitivity. Edge effect is the phenomenon that sharp edges cause much more viscous drag. This work researches edge effect's influence on viscous drag to speed up the rotor. Flow field models of the sharp edge structure and fillet structure are established separately. Viscous drag is measured by simulation and experiment. Edge effect causes a lot of viscous drag and it can be reduced significantly by filleting the rotor. The maximal reduction is one third relative to the sharp edge structure, and it is reached when fillet curvature radius is half of rotor thickness.
Design of Hall Vehicle Speed Sensor Comprehensive System
Authors: Qin Zheng Kun , Li Shu Yuan , Wang Chun Wu , Wang Guo Feng
Published: July 2013

A hall speed sensor detection system is designed in this paper. The system consists of the controlling circuit part, the detecting circuit part and the microcomputer part. The system’s structure is simple. It has the advantages such as lower cost, intuitive display and user-friendly. The detecting accuracy can meet the requirements of industrial production, and be suitable for mass production.
Fundamental Study of the Micro-Cantilever for more Sensitive Surface Stress-Based Biosensor
Authors: Feng Hui , Sang Sheng Bo , Zhang Wen Dong , Li Gang , Li Peng Wei , Hu Jie , Du Shao Bo , Wei Xiu Juan
Published: July 2013

Surface stress-based biosensors as a crucial part of micro-scale and label-free system, use free energy change, the underlying concept in any binding reaction, have been investigated extensively in recent years. In this paper, a new bi-micro-cantilever surface stress biosensor is proposed which can be used to detect cells. Some fundamental study has been done, especially for the micro-cantilever due to its crucial role in the whole system. To acquiring the optimal material for more sensitive sensor, four material, Si, SiN, AlN, PMMA(polymethylmethacrylate), were contrastively analyzed under the same conditions (loads, size, environmental factor. etc) by finite element (FE) method. This study could provide some foundation for the biosensor design and fabrication.
A High Bandwidth Sigma-Delta Modulator Applied in Micro-Gyroscope
Authors: Fu Qiang , Chen Wei Ping , Chen Song , Wang Peng Fei , Liu Xiao Wei
Published: July 2013

In this paper a fourth-order single-loop sigma-delta modulator applied in micro-gyroscope is designed. The modulator system chose the fully feedforword structure. The signal bandwidth is 200KHz, oversampling ratio is 64 and sampling frequency is 25.6MHz. By system simulation result in Matlab, the signal to noise ratio (SNR) is 92.3dB and effective number of bits (ENOB) is 15.03bits. The whole circuit of modulator is designed and simulated in Cadence Spectre. It is gotten that the SNR is 78.6dB and changes linearly with input level. When input level is bigger than -4dBFs, the modulator becomes overload.
Design and Fabrication of a Novel Biaxial Piezoelectric Micro-Gyroscope
Authors: Guan Ran , Zhang Wei Ping , Zhang Gong , Cheng Yu Xiang , Chen Wen Yuan , Wu Xiao Sheng , Cui Feng , Liu Wu
Published: July 2013

Despite the popularity of piezoelectric vibratory micro-gyroscope in the past decades for their small size, low cost, batch fabrication and energy efficient, most of them can only detect single axis angular rate. In this paper, a novel biaxial piezoelectric micro-gyroscope fabricated with PZT wafer is proposed. To acquire two-axial angular rate sensing, a bouncing mode of the vibrator is utilized as the drive mode and two rocking modes are used as the sense modes. PZT is used as the vibration body instead of transducer, which enhances the drive and sense efficiency of the sensor. In this paper, the structure and working principle of the novel biaxial piezoelectric micro-gyroscope are introduced firstly. In addition, modal analysis has been made to research the voltage distribution of the piezoelectric vibrator and the drive and sense electrodes of the gyroscope are designed. By the optimization design of the proof mass, the frequency split between the drive mode (bouncing mode) and sense modes (rocking modes) is reduced and the sensitivity of the gyroscope is improved. Harmonic analysis has been made to research the Coriolis Effect of the gyroscope. The data get from the harmonic analysis is demodulated by Matlab and the sensitivity is given. The simulation results verify the principle of the novel biaxial piezoelectric micro-gyroscope. With the optimized design, the sensor is fabricated with MEMS technology at last.
Fabrication of the Nanoscale Flat-Bottomed and Lamellar Structures on HOPG Surface by STM-Based Electric Lithography
Authors: Yang Ye , Zhao Wan Sheng
Published: July 2013

The requirement for fabrication of the nanometer-scale structures has grown up recently due to the advance in the development of the nanoscale electronic-devices or bio-devices. Scanning tunneling microscope (STM)-based electric lithography is one of the potential fabrication approaches to produce nanoscale structures on a variety of materials. This study of the STM-based electric lithography intends to fabricate flat-bottomed and lamellar structures on the graphite surface, which differs from the conventionally fabricated tapered structures. The formation and the comparison of both the lamellar and tapered structures are obtained by applying distinct STM tip geometries in the STM-based electric lithography. On the basis of the experimental results, it is found that the formation of lamellar structures should be attributed to the local electrochemical reaction, while the generation of tapered structures is resulted from the dielectric breakdown in the tip-sample gap.
Simulation Research on Micro-Cavity Flow Field Characteristics of Liquid Floating Rotor Gyro
Authors: Shi Yu Peng , Tang Fei , Wang Xiao Hao
Published: July 2013

The liquid floating rotor gyro is a gyroscope using electrostatic or electromagnetic forces to levitate rotor, and filling rotor-stator cavities with liquid in order to improve stability of motion. Under influence of the relative surface roughness, rotor velocity, dimension of flow field and fluid nature, flow characteristics of cavity flow field vary under different boundary conditions and geometrical conditions. This paper adopts three-dimensional model and periodic boundary conditions to conduct numerical modeling on cavity flow field. Its results show that, with velocity rising, distribution of flow field speed and pressure manifests partial fluctuations in turbulent-flow-intensive area; resistance torque amid rotor rotation is nonlinearly correlated with velocity, whose rules can be obtained through high-order curve fitting.
Bouc-Wen Model Parameter Identification for Piezoelectric Actuator Using Chaos Particle Swarm Optimization
Authors: Cai Chun Xia , Liu Xiang Dong , Dong Ning , Li Hong Juan
Published: July 2013

This paper mainly proposes a chaos particle swarm optimization (CPSO) to estimate the parameters of piezoelectric actuator (PEA), in which Bouc-Wen model is employed to describe the hysteresis phenomenon. By introducing chaotic disturbance to the simple PSO, this method can obtain optimal solution with high calculation efficiency. Finally some experiments are conducted to demonstrate its feasibility and effectiveness.
A Novel Microfluific Design for Cell Culture and Test
Authors: Zhang Wen Dong , Tang Xiao Liang , Sang Sheng Bo , Du Shao Bo , Li Peng Wei , Hu Jie , Li Gang
Published: July 2013

Cellular culture is a complex process for cells are grown under certain given conditions, generally not in vivo. In this paper, a novel microfluidic was designed for cellular culture in a long term. Its structure mainly consists of two parts: channels and chambers. In this architecture, two kinds of channels are designed. One is used to load cell into chambers, the other is for the load of culture solution and drugs. Due to diffusion effect, the culture solution and drugs can permeate into chambers through a amount of ostioles. Finite element simulation was utilized to demonstrast the velocity field distribution and concentration field distribution. Comparisons were made to verify the rationality of the design. The simulation results suggest that this novel microfluidic is appropriate suitable in terms of culturing cells.
Fabrication of ZnTiO3 Nanofibers by Electrospinning
Authors: Sang Rong Li , Shao Jun , Wang Lin
Published: July 2013

Ultrathin fibers of PVP/ZnTiO3 composite were prepared through sol-gel processing and electrospinning technique. After calcined of the above precursor fibers at 600°C, the spinel ZnTiO3 nanofibers, with a diameter of 50-150nm, were successfully obtained. The fibers were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and fourier transform infrared (FT-IR), respectively. The results displayeded that the morphology and crystalline phase of the fibers were largely influenced by the calcination temperature. The reported strategy will be useful for fabricating one-by-one continuous nanofibers, which are suitable for applications in catalysis, chemical sensors, nanoelectrodes, and nanodevices.
Design and Fabrication of a Lateral Contact RF-MEMS Switch for MM-Wave Applications
Authors: Zhu Yan Qing , Han Lei , Tang Jie Ying , Huang Qin Gan
Published: July 2013

Design, fabrication and test results of a lateral DC-contact RF-MEMS switch for mm-wave applications are presented. The switch is driven by a triple cascaded electrothermal buckle-beam actuator, which can generate large displacements and contact forces at lower temperatures than traditional electrothermal actuators. The size of the whole switch is only 1.2 mm × 1.4 mm in area. The measured transient times for switch-on and switch-off are 13.6 and 0.96 ms, respectively. Low insertion losses and high isolation of 0.17 dB and 26.7 dB, respectively, are obtained in the proposed switch at center frequency of 35GHz, the insertion losses less than 0.5dB and the isolation better than 22.5dB can be achieved in the proposed switch at 30~40GHz. The reasonable agreement between design and measurement is observed.