bluuebunny/crossref_metadata_2025 huggingface dataset:
The Study on Embedded Systems Capstone Design
Authors: Ma Dong Tao
Published: January 2012

We reviewed an introductory course in embedded systems, it is not in the embedded system resource constraints, but depends on the interaction between the physical world. This course teaches students the basic model, and analysis tools, design in embedded systems use. The traditional undergraduate courses in embedded systems focus on AD hoc of engineering practice, the use of existing modeling technology, often omitted critical analysis and meta-modeling; We emphasize cyber-physical design model and the embedded system. Students will learn how to model the physical world differential equation and continuous time, and how to use logic model calculation model and discrete state machine. Officially designated verification technologies, want to act. Structure design project for the laboratory and conception is applied in the design of the embedded system and cyber-physical to provide real-time, parallel behavior.
Research on Dynamic Characteristic and Experiments of Double-Disc Rotor System with Oil Film Support
Authors: Li Chao Feng , Liu Jie , Li Qin Liang , Wen Bang Chun
Published: January 2012

Multi-DOF model of double-disc rotor-bearing system taking oil film support into account is established, and Newmark method is also applied to dynamic response of continuous system. To simplify the calculation in double-disc eccentric situation, the research aims at time domain, frequency response and bifurcation solution, simultaneously qualitative experiments are also carried out on the experiment bench. Experiments show that the numerical algorithm and calculation results are credible. The conclusions conclude: For the rotor system shown in the paper, with the other parameters constant, small eccentricity system is prone to appear quasi-periodic instability, but for big eccentricity system it is period-doubling instability, and the instability speed will increase with eccentricity enlargement; initial eccentric phase has severe effects on the dynamic characteristic of system, so it is worth studying it more in depth. This method and results in this paper provides a theoretical reference for stability analysis and vibration control in more complex relevant rotor-bearing system.
Dynamic Fatigue Simulation of Engine Block Based on Virtual Prototype Technology
Authors: Liu Na , Li Guo Xiang , Wang Ting Ting , Hu Yu Ping , Liu Xiao Ri
Published: January 2012

This paper carried out simulation analysis on the dynamic fatigue strength of an inline six-cylinder engine block based on the measured indicator diagram by the means of virtual prototype technology. A 3D solid model of the crankshaft block system is established firstly. After that, based on finite element method, dynamic stress of the block under operating conditions is obtained, by the means of Multi-body dynamics method. Then, calculation analysis on the fatigue safety coefficient of the engine block is made.
The Design and Research of the Flight Simulator Motion System and Visual System
Authors: Wang Chun Guang , Yue Shuai
Published: January 2012

Based on the motion system and visual system design of flight simulator, the software and hardware design in motion system and visual system of flight simulator is regared as key problem. The fidelity automatic test system is discussed. The aim is to explore a complex system integration method. The fidelity automatic test system is used to detect the fidelity of motion system and visual system. The results show that the design of motion and visual system is reasonable and the performance can meet demand of fidelity.
Effect of Sintering Temperature on Electrical Properties of ZnO Varistor Ceramics
Authors: Xia Chang Qi , Liu Qi Bin , He Mo
Published: January 2012

To obtain ZnO varistors with high voltage gradient, ZnO varistors were fabricated by traditional ceramic sintering technique, the effect of different sintering temperature (1135～1155 °C) on electrical properties of ZnO varistors were investigated. The experimental results show that with increasement of sintering temperature, the grain size of ZnO varistor ceramic becomes bigger, the voltage gradient of varistor decreases and the density is improved. When the sintering temperature is at 1135 °C, the voltage gradient of varistor is up to 329V/mm, the leakage current is 8μA and the density is 96.4%. When the sintering temperature is at 1140 °C, the voltage gradient of varistor is 301V/mm, the leakage current is 4μA and the density is 96.6%. Compared the results at 1135 °C with 1140 °C , it is found that the comprehensive electrical properties of ZnO varistors reach maximum at 1140 °C.
Plastic Classification by Trademark Based on near Infrared (NIR) Spectroscopy Data
Authors: Wang Jing Jing , Hou De Xin , Wu Bei Lei , Ye Shu Liang , Yang Heng
Published: January 2012

Quality control of plastic for avoiding environmental pollution and food poisoning is of utmost relevance and it is a common requirement in national norms for health and safety reasons. Among series of factors, trademark plays an integral role in the procedure which must be properly classified in order to reduce risk loss of distinctiveness. As most norms rely on chemical or physical experiment, chemometric classification models from NIRS spectra were tested for sampling polyethylene that presents potential effect of trademark by using Soft Independent Modeling of Class Analogy (SIMCA) and Factor Analysis in this paper. The classification models were carried out with two kinds of trademarks (F410-3 and LA0710) of 50 test samples from Singapore and Qatar respectively. And the experimental results show that the SIMCA classification obtained 88% accurate identifications, while Factor Analysis gives 100%. By using this strategy, it was feasible to conclude a better method to classify plastic quickly and nondestructively without the need for various analytical determinations.
Design and Implementation of Bridge Structural Health Monitoring System
Authors: Rao Hong , Zhao Hui , Li Shan , Li Mu Zhu
Published: January 2012

Bridge Health Monitoring System (BHMS) is a combination of sensor monitoring technique and network communication technique, in charge of working status inspection and health detection and alarm via filed data, providing a solid safeguard for the well-balanced operation of the bridge as well as the security of people’s life and property. In this paper, it offers a solution plan which based on S2SH architecture. It describes the design and implementation process of the bridge structural health monitoring system, by using Extjs which brings better user experience.
Based on RSSI Ranging Technology for DV-Hop Localization Algorithm of Wireless Sensor Network
Authors: Zhong Yang Jun
Published: January 2012

For the DV-Hop algorithm of wireless sensor networks,there is an error arising problem that anchor nodes and location node hop distance is only an approximate calculation. A method based on the original Algorithm introducing RSSI ranging technique is proposed.Using RSSI ranging technology,we accord that if the anchor nodes is only a hop away from the location node,then decide whether using the DV-Hop algorithm to approach to the approximate distance between them. Simulation results show that the algorithm can effectively improve the error problems of calculating the hop distance between the anchor nodes and the location nodes, meanwhile improve the positioning accuracy of the node.
Effect of Equivalence Ratio on Propagation Process of Combustible Gas in Venting Tube
Authors: Ren Shao Feng , Chen Xian Feng , Wang Yu Jie , Zhang Yin
Published: January 2012

To explore the effect of equivalence ratio on the propagation process of combustible gas in the venting tube, in the present study, the κ-ε turbulent model and the combustion models were implemented base on unaltered venting conditions and different equivalence ratio of methane-air. In particular, the numerical simulation results illustrate both speed and pressure were at maximum when equivalence ratio was 1.0. However, methane-air didn't reach the most sufficient combustion when equivalence ratio was 1.0. It was possible that the pressure release caught the equivalence ratio change and failed to generate detonation.
The Design of Vehicle Integrated Navigation System Based on FPGA
Authors: Wei Yong Sen
Published: January 2012

A GPS/inertial navigation system design scheme is introduced. Combination of DSP and FPGA is used on the navigation board, and micro inertial navigation measuring element --ADIS16405 is used to sample required navigation data. DSP mainly implements navigation calculating based on navigation data, and realizes different navigation algorithms; FPGA in the system plays centeral control role, and not only samples IMU and GPS data, but also synchronize IMU and GPS in the real time, and preprocess and packet the navigation data. This paper also introduces the design of the software on FPGA. Practice proves that the scheme is feasible, and achieves the good balance between the cost, reliability and efficiency.
Design of the Remote Liquid-Level Real-Time Monitoring System Based on Virtual Instrument
Authors: Yu Yan Xin , Chen Yu , Song Xue
Published: January 2012

Real-time accurate level monitoring plays an important role in the field of industrial and agricultural production. In this paper, the remote real-time monitoring display system of liquid level was designed based on virtual instrument. The liquid-level data was obtained from ultrasonic sensor and data acquisition card, and then was transmitted to a remote client via ethernet without delay by the DataSocket technology. The real-time information of liquid level was displayed on the user interface of the client which was compiled based on LabVIEW. Test results show that this system can accurately monitor the remote real-time information of liquid level.
Synchronization Controlling for a Permanent Magnet Synchronous Motor via Linear Feedback with Single State
Authors: Jian Ji Gui , Zhao Zhi Hua , Wang Wei Wei
Published: January 2012

This paper treats the globally exponential synchronization problem of the permanent magnet synchronous motor chaotic system. Based on Lyapunov stability theory and some inequalities techniques, one novel control approach, namely linear feedback control with one state is proposed to realize the globally exponential synchronization of two permanent magnet synchronous motor chaotic systems. In this case, some sufficient conditions for the globally exponential synchronization of two chaotic systems are obtained analytically. The controllers here designed have simple structure and less conservation. The numerical simulation results show the effectiveness of the method.
Design and Control of a Mini Quad-Rotor UAV Based on Embedded System
Authors: Du Man Man , Jin Feng
Published: January 2012

In this paper, one kind of quad-rotor UAV (unmanned aerial vehicle) controller is designed according to analyze its structure and function. The hardware platform is established based on DSP MC56F8037, inertial sensor unit, as well as facilities that make it suitable for the dynamic system. According to the analysis of the working principle of the quad-rotor, the nonlinear dynamic model is established. This is a hierarchical embedded model based control scheme that is built upon the concept of backstepping, the simulation result shows the controllers are valid. This realization makes a great progress in the development process of a more advanced realization of an UAV suitable for practical applications.
A New DYC Control Strategy Based on Feedforward Control in the Linear Region
Authors: Wang Qi Dong , Huang He , Chen Wu Wei
Published: January 2012

This paper discussed a new direct yaw moment control(DYC) method which was coupled with feedforward control by utilizing the estimated cornering stiffness coeficients. Comparing two simultaneously running single track models in the linear region,the feedforward control output was produced. Higher-order sliding modes(HOSM) was used to ensure the robustness of the control system in the limit region. A weight gain was used to combined feedforward control and feedback control. The simulation results in VeDYNA show that this new DYC control method based on the knowledge of cornering stiffness signiﬁcantly improve the vehicle desired trajectory over that of feedback control alone.
A Nano-SiO2 Form-Stable Phase Change Material for Building Thermal Energy Conservation
Authors: Lin Wei Jun
Published: January 2012

A stable form-phase change materials (PCM), based on capric-lauric acid eutectic served as the absorption material and the support of nano-silica material to prepare by sol-gel method. The best ratio capric-lauric acid eutectic combination is determined for 60 wt. %. Capillarity because of the influence of the hydrogen bonding, fatty acid and eutectic can be fixed in the three dimensional network structure of the construction of the silicon atom bonds and O still so solid sample melting point composite heating more fatty acid eutectic. Form and chemical properties of the composite phase change the transmission electron microscope, semi and Fourier transform infrared method.- Differential scanning calorimetric hot method is used for measuring phase transition temperature and phase change of latent heat composite, value 19.57 and 71.28 J/g , respectively. At the same time, service performance and other composite material thermal stability and thermal conductivity coefficient test using thermo gravimetric analysis and transient hotline method, respectively.
Research on LPG Dual-Spark Ignition Engine Combustion by CFD
Authors: Zhou Dong Qing , Li Jun , Gao Ying , Qu Da Wei , Liu Qi Jie
Published: January 2012

.To study the dual-spark ignition methods of combustion of LPG, numerical simulation is conducted on the lean burn LPG turbocharged engine by three-dimensional simulation software.Based on the model validation test of dual-spark ignition model engine, the effect of synchronization ignition and asynchronous ignition are discussed.The results obtained show that asynchronous dual spark ignition model can be helpful to reduce flame propagation distance, form the stronger swirl rapidly,accelerate the flame propagation speed significantly,improve the rapid lean-burning process of LPG engine. Meanwhile, the results will also offer theoretical guidance for combustion optimization.
Technology of Magnetic Flywheel Energy Storage
Authors: Qi Xiu Li , Zhang Kang , Wang Guang Xian , Fu Zhen , Dong Yi Chen
Published: January 2012

.As a new way of storing energy, magnetic suspension flywheel energy storage, has provided an effective way in solving present energy problems with the characteristics of large energy storage, high efficiency and fast charge-discharge speed and so on. The paper mainly elaborated the basic principle of magnetic suspension energy storage system, introduced the structural features of flywheel rotor, magnetic bearing, electric machine, electric power system and other auxiliary body. On this basis, it analyzed applications on electrical peak-modulating, Uninterruptible Power Supply, Hybrid Electric Vehicle, satellite attitude control and so on, on the purpose of the further development and promotion of this new technology.
MEMS Gyro Aided Calibration of Electronic Compass
Authors: Li Xi Sheng , Liu Yan Xia , Shu Xiong Ying , Kang Rui Qing
Published: January 2012

In this paper, an MEMS gyro aided on line calibration algorithm for electronic compass is presented. This electronic compass module consists of a three-axis AMR sensor, a two-axis MEMS tilt sensor and a one-axis MEMS gyro. The automatic calibration method requires to rotate the electronic compass two full 360-degree revolution. In this rotation procedure, magnetic field data, attitude data and angular rate data are recorded. Based on recorded magnetic field data and attitude data, raw heading data is calculated. This raw heading data is verified by angular rate output of MEMS gyro. Results of experiment show that the accuracy of calibrated compass is better than 0.5 deg and MEMS gyro aided on line calibration algorithm is effective for electronic compass.
Research on the Mathematics Model of a Permanent Magnet Linear Oscillatory Actuator with Moving Iron and Non-Salient Pole
Authors: Pan Hai Peng , Wang Yang , Xia Yong Ming , Zhang Wei
Published: January 2012

A novel permanent magnet (PM) linear oscillatory actuator (LOA) of moving-iron and non-salient pole was presented on the basis of LOA research. The mathematical model of the LOA based on the magnetic circuit method was established, and derived the relationship between electromagnetic thrust and coil current, mover’s displacement. The thrust of LOA was simulated by the Finite Element Method (FEM). The corresponding experimental results verifies the electromagnetic thrust is direct proportional to coil current and reverse proportional to mover’s displacement during effective mover’s displacement. So the derived mathematical model based on the magnetic circuit method is correct. This conclusion provides a theoretical basis for the further calculation of thrust, the selection of control current and the design of controlling method.
Selection of Mixed Refrigerant for CBM Liquefaction System and its Optimization Analysis
Authors: Fan Q.H. , Li H.Y. , Jia L.X. , Fan Q.H. , Shao Yi Min , Zhan X.H.
Published: January 2012

In the mixed refrigerant cycle, the key technology is the choosing of the mixed refrigerant and its optimization mixture ratio. Based on a small-scale CBM liquefaction system LNG5, which the capacity is 5 cube meters LNG per day, the numerical simulation and optimization for the LNG5 are carried out. It provides the composition of the mixed refrigerant. It analyzes the effects of mixed refrigerant components on the temperature difference of the heat exchangers and the vapor fraction of the key nodes. The analysis results show that a reasonable mixture ratio of mixed refrigerant is given, such as CH4 mole fraction being 41.8% ～ 44.3%, C2H6 mole fraction being 40.8% ～ 42.2%, C5H12 molar fraction being 14.3% ～ 16%, and N2 mole fraction being 1.5% ～ 3.3%. The results provide guidelines for the design of the small-scale CBM liquefaction device, and for the application and commissioning of CBM liquefaction plant in China.
Research on Filament Composite Winding CNC/TCS Integration System Based on Open-Architecture
Authors: Wang Shi Huan , Gao Jun
Published: January 2012

Filament tension control system is integrated into real-time core of open-architecture winding CNC. Based on filament tension generation theory for filament wound component, the method of process elimination is applied to modify the theory of filament tension control to transform uncontrollable elastic tension to known quantity, thus improves the control precision of tension in filament composite wound components. (Abstract)
Partial Postponement Strategy: Application in Automobile Manufacturers
Authors: Wang Xia , Xie Zhi Min , Guan Xian Jun
Published: January 2012

Based on the analysis of previous research results, A partial postponement strategy, which is a production mode with the combination of “make-to-stock” and postponement, is regarded as an appropriate strategy and should be implemented in the automobile manufacturers. A quantitative decision-making model is proposed in this paper. The proposed model, with customer waiting time as the constraint, aims to study the postponement probability which can minimize the total cost (including production cost, inventory cost and customer waiting cost). The application of partial postponement strategy in Corporation Q by the proposed model is analyzed in the next part of this paper. The results can help Corporation Q set its proper postponement probability to satisfy individual requirements at the lowest cost.
The Research on Applying High Precision Ultrasonic Ranging in the Auto-Levelling System of Paver
Authors: Xiao Jiang , Yu Zhou Yan
Published: January 2012

Paver can finish paving, ramming and pressing in a time, with certain density, thickness, width. It is suitable for various grades of highway, airport and road construction. The auto-levelling system, as an important part of paver, makes paver simple operation, safe and reliable, greatly reduce the loss of raw material and manpower, and the control accuracy directly influences the quality of paving flatness. The problems faced of auto-levelling system are introduced firstly. Secondly, ultrasonic sensor range finder technology at home and abroad and the present situation and basic principle, characteristics of ultrasonic sensor are clarified. Third,the range affecting factors of the ranging accuracy are found and appropriate method is put forward to compensating and correcting. Eventually, the method applied in the CPLD EPM570T100C5N, based on the C8051F040 singlechip , ultrasonic ranging circuit are formed. This paper illustrates the hardware and software design of every circuit module.
Fiber Grating Sensor Temperature Prediction Based on Relevance Vector Machine
Authors: Liu Fang , Yu Lei , Li Yan
Published: January 2012

Fiber grating sensor network plays an important role in evaluating the bridge health condition and gaining bridge structure characteristic.Bridge structural distortion and variation of stress is associated with temperature.So it is essential to make temperature prediction bases on the length of wave which gained from fiber grating sensor network system.Traditionally, we apply least square method to predict temperature.In this paper,we use method of relevance vector machine (RVM) to make it.
Non-Fragile Robust Controller Design for Nonlinear Stochastic System with Time-Delay
Authors: Li Ya Jun , Deng Fei Qi , Peng Yun Jian
Published: January 2012

The problem of non-fragile memoryless controller design for a class of uncertain nonlinear stochastic system with time-delay is considered. Based on Lyapunov candidate and the stochastic Lyapunov stability theory, the sufficient conditions making the closed-loop system robust stable are given and de-rived. All results are given by the form of linear matrix inequality (LMI) method. Numerical example is given to illustrate the effectiveness of the controller designed.
Low Temperature Performance of Fiberglass Geogrid
Authors: Xu Yong Li , Zhang Bai Zhen Ming , Tao Le , Xing Zhen Zhen
Published: January 2012

The tensile test to the fiberglass geogrid had been carried on, in the normal temperature, the low temperature, the water immersion, the freezing and the freeze-thaw cycle and so on conditions. The results indicated, the fiberglass geogrid had achieved saturated after been immersed 12h, the water absorption was about 20%, the tensile strength reduced approximately 80%; the tensile strength was dropped slightly on the next freezing test and the freeze-thaw cycle test. So it could be stated that the fiberglass geogrid had the good low temperature performance. Then the interlaminar shearing test had been conducted in the different temperature to the composite structure in which the fiberglass geogrid was laid or not. The result showed that the interlaminar shearing strength had weaken about 20% when laid down the fiberglass geogrid, and along with temperature drop, the shearing strength increased gradually. This research provide the reference for used the fiberglass geogrid correctly in the cold region, had great practical value.
Effect of the Y2O3 Addition Content on the Structural Properties of ZrO2 Thin Films and Coating Material
Authors: Wu Shi Gang , Zhang Hong Ying , Shao Jian Da , Fan Zheng Xiu
Published: January 2012

The influence of addition of Y2O3on the structure of ZrO2thin films and bulk material was studied employing X-ray diffraction (XRD) analysis. The films were prepared by the electron-beam evaporation method. XRD analysis permits the study of the stabilization process. For pure ZrO2thin film and coating material, the crystallographic structure is monoclinic phase; with increasing Y2O3mole percent, the structure of Y2O3stabilized ZrO2(YSZ) material changes from a mixture of monoclinic and cubic phase to a single cubic phase. Furthermore, calculated results of grain size show that YSZ thin film and coating material have the same crystallization trend.
Numerical Simulation of Sheet to Cylindrical Tube Single-Sided Spot Welding
Authors: Yang Hong Gang
Published: January 2012

With the promotion of lightweight structure, hydroformed tubes have been widely used in the automobile industry. In order to join different parts, sheet to tube single-sided spot welding (SSSW) is proposed. In the present study, numerical simulation method is employed, and an electrical-thermal mechanical coupled finite element model is established for predicting the nugget size and shape of sheet to cylindrical tube SSSW. Because of the welding deformation, doughnut weld nugget is formed and the course of the welding deformation can be reflected by the electrode displacement.
Analysis on Dynamic Characteristics of CNC Machine Tool and Experiment with Influence of Rolling Guide Joint Considered
Authors: Li Xiao Peng , Nie Hui Fan
Published: January 2012

The 3D finite element model of CAKxxx CNC machine tool is established and the static/dynamic characteristics of the machine tool are analyzed with finite element method when the influence of the linear rolling guide (LRG) joint is considered or neglected. The lowest five natural frequencies and vibration modal shapes are obtained in both cases. It shows that when considering the influence of the LRG joint, each of the lowest five natural frequencies is 14 Hz smaller than the results of neglecting the influence, and the vibration modal shapes are more stable. The modal experiment shows that the results of considering the influence of the LRG joint are closer to the actual situation. It also proves that LRG joint has great influence on the dynamic characteristic of the machine tool. It provides an important reference for accurate modeling and dynamic design of machine tool.
Aerodynamic and Heat Transfer Simulation of Cooling Turbine Blade with Different Tips
Authors: Yu Kua Hai , Yang Xi , Wen Zhi Xun , Yue Zhu Feng
Published: January 2012

This paper studies the aerodynamic and heat transfer influence of tip structures for cooling turbine blade. Four blades with different tip features are discussed, and coupling aerodynamic and heat transfer method is used to accomplish the simulation. The results show that squealer tip can greatly reduce the heat transfer between tip surface and high temperature gas, and also it reduces tip leakage, to some extent. That’s because it exists obviously eddy near the tip surface. Tip injection holes can cool the tip surface effectively, and it will greatly reduce the temperature of tip surface. However, injection holes improve tip leakage slightly.
Analysis on Stress Characteristics of Rolling Body of Rolling Dryer
Authors: Ren Zhao Hui , Hao Yuan
Published: January 2012

Rolling dryer is one kind of dryer device with large output. The characteristic of rolling body has great influence on the output of dryer. In the paper, with the finite element method, the stress distribution of body, bolt hole, man hole and modes of rolling body are obtained by static stress and modal analysis and study of acting loads on rolling body. The results can help to enhance the efficiency of rolling dryer and provide corresponding theoretical supports for the design and manufacture of the machine.
Analytical Modeling of the Spindle Shaft of Heavy Load Deflection Angle Milling Head Dynamics Using Timoshenko Beam Model
Authors: Ma Shi Ming , Cai Li Gang , Zhao Yong Sheng , Liu Zhi Feng , Guo Tie Neng , Cheng Qiang
Published: January 2012

The spindle shaft of heavy load deflection angle milling head is an important functional component of 5-axis CNC machine tool, which has characteristics of high torque and high power, used for large and complex free-form surface processing. The spindle shaft is modeled as Timoshenko’s beam by including the centrifugal force and gyroscopic effects. The effects on inherent characteristic of the spindle shaft of heavy load deflection angle milling head are analyzed owing to axial force and spindle shaft speed. Simultaneously, numerical solution of spindle shaft is gotten. And, the numerical results are well agree with the exact modeling, which illustrates that the theoretical modeling of spindle shaft is correct and the exact dynamic characteristics of spindle shaft is obtained. The analytical modeling results of spindle shaft are effective and helpful for design and improvement of spindle shaft of heavy load deflection angle milling head.
Study on Superposed Magnetic Field ECM of Square Hole
Authors: Jia Jian Li
Published: January 2012

To improve the Electrochemical Machining accuracy and little stray corrosion of shaping hole, one scheme is adopted to carry on the technical experiment, which inserted the permanent-magnet into the core of cathode in the square hole separately. Compared with the experiment of Electrochemical Machining without magnetic field, the magnet around the core of cathode inlaid with the magnet is in favor of improving machining accuracy under the same processing parameter, and helpful to reduce the stray corrosion.
Research on Blockage Damage Effect of Fragment Warhead to Target on Ground
Authors: Huang Guang Yan , Feng Shun Shan , Liu Pei Qing , Liu Chun Mei
Published: January 2012

The blockage damage to the movable target on the ground with the mode of deterring is an important aspect of research about the fragment warhead. The analytic method of damage power about the blockage warhead cluster with the three blockage districts, including districts of dense damage in close distance, sparse damage in middle distance and deterrence damage in wide distance, was raised to do the research on the designing method of blockage damage warhead and the evaluation of blockage damage effect. The lying and standing static effectiveness test of the blockage warhead were designed based on the special blockage damage character. The designing method of the blockage damage warhead and the analytic method of blockage power characteristic were proved to be scientific, and the researching is significant in project application.
Computer-Aided Material Classification Coding Model and Software System for Mechanical Product
Authors: Li Zhong Kai , Bai Tao , Qiu Le Miao
Published: January 2012

For the large numbers of material classification coding rules and components in manufacturing enterprises, a computer-aided material classification coding model is proposed, in order to improve the inputting efficiency of part codes. Based on the analysis of the material classification and coding rule for mechanical product, four types of code segments which suited for computer assisted are put forward. The application and database storage models of the coding rule are built up. Moreover, the paper describes the computational workflow of computer-aided coding and its kernel algorithm to acknowledging the related classified segment. The effectiveness and modularity of the prototype system is illustrated by the implementation in an electronics manufacturing corporation.
Laser Diagnostic Investigation on the Spray and Combustion with Butanol-Biodiesel-Diesel Fuel Blends
Authors: Liu Yu , Li Jun , Gao Ying , Yuan Xin Mei
Published: January 2012

. In this paper, blends of butanol-biodiesel-diesel were tested inside a constant volume chamber to investigate liquid spray and combustion of the fuels. With high-speed camera and synchronized copper vapor laser, spray penetration during injection is recorded since it has a higher light reflectivity. Various ambient temperatures and fuel composition were investigated. There is a sudden drop in spray penetration at 800 K and 900 K, but not at 1000 K and 1200 K. When the spray penetration of the butanol-biodiesel-diesel blends is compared to that of the biodiesel-diesel blends, under non-combusting environment, a sudden drop in spray penetration length is also observed at 1100 K. High speed imaging shows that, for the non-combusting case, at 1100 K, the tip of the spray jet erupts into a plume sometime after injection for the butanol-biodiesel-diesel blend. The same is not seen with the biodiesel-diesel blend, neither at lower ambient temperature of 900 K. It is concluded that micro-explosion can occurs under particular conditions for the butanol-biodiesel-diesel blend, and the results is consistent with previous study in the literature.
A Comparative Study of Impression Procedures for Distal Extension Removable Partial Dentures
Authors: Tavane Pradeep N , Abraham Sathish , Madihalli Anand U , Yadav Naveen S , Reddy P Manoranjan , Baiju G
Published: January 2012

Aim

This study was carried out with the purpose of comparing three impression methods as to which of them placed tissues most favorably.

Methods

The methods used were Hindels method, selective tissue placement method and functional reline method. The measurements obtained were analyzed to determine which of the three impression methods placed the mucosal tissues maximally. To compare and measure tissue placements, autopolymerizing acrylic resin platforms were constructed to the height of the occlusal surfaces of the remaining teeth. 15 orthodontic buccal tubes were placed on each side of the platform. They were arranged in three sets of five and attached to the platform over selected reference regions by means of autopolymerizing resin. The selected reference areas were in anterior, middle and posterior areas of the ridge on either side.

Results

No significant difference was seen in tissue placement in the anterior middle and posterior regions in each of the three methods when each method was assessed separately. Selective tissue placement method placed the tissues maximally (7.547 mm) followed by Hindels method (7.2110 mm) and the least placement was by functional reline method (5.856 mm). Tissue placement was significantly higher in Hindels method as compared to functional reline method (p < 0.001).

Conclusion

Tissue placement was maximum in the posterior region, followed by the middle region and least in the anterior region of the mandibular ridge for all three methods. Selective tissue placement method showed the maximum overall tissue placement followed by the Hindels method and minimum placement was by functional reline method.

Clinical significance

Selective tissue placement method provided maximum overall tissue placement and can be a preferred technique for impression making for bilateral distal extension removable partial denture fabrication.

How to cite this article

Madihalli AU, Tavane PN, Yadav NS, Abraham S, Reddy PM, Baiju G. A Comparative Study of Impression Procedures for Distal Extension Removable Partial Dentures. J Contemp Dent Pract 2011;12(5):333-338.
Analysis of the Properties of Dental Cements after Exposure to Incubation Media containing Streptococcus mutans
Authors: de Menezes Fernando Carlos Hueb , Júnior Geraldo Thedei , de Oliveira Wildomar José , de Paiva Paulino Tony , de Moura Marcelo Boaventura , da Silva Igor Lima , de Moura Marcos Boaventura
Published: January 2012

Aim

Indirect restorations are increasingly used in dentistry, and the cementation interface is possibly the most critical region of the work. The objective of the present work was to evaluate the influence of exposure to a culture medium containing S. mutans on the hardness and solubility of four different cementing agents (zinc phosphate, glass ionomer, glass ionomer modified with resin and resin cement).

Materials and methods

Test specimens composed of these cements were exposed for 30 days in a culture medium containing S. mutans. After leaching, the test materials were assessed in terms of their solubility (loss of mass) and Knoop (KHN) microhardness. Changes in surface morphology were identified using scanning electron microscopy (SEM).

Results

The resin cement showed no significant solubility and its hardness increased following exposure and leaching, while the zinc phosphate cement was the most soluble and its hardness decreased after exposure to the culture medium. SEM analyses identified morphological alterations on the surfaces of the test materials that were compatible with the solubility results.

Conclusion

It is concluded that resinous cements perform better than water-based cements when exposed to acidic conditions.

Clinical significance

The effects of acids from Streptococcus mutans can interfere with the efficiency and properties of some cements used for fixation of indirect restorations, exposed to the buccal environment.

How to cite this article

de Menezes FCH, Júnior GT, de Oliveira WJ, de Paiva Paulino T, de Moura MB, da Silva IL, de Moura MB. Analysis of the Properties of Dental Cements after Exposure to Incubation Media containing Streptococcus mutans. J Contemp Dent Pract 2011;12(5):385-391.
Transport of short-lived species into the Tropical Tropopause Layer
Authors: Ashfold M. J. , Harris N. R. P. , Atlas E. L. , Manning A. J. , Pyle J. A.
Published: January 2012

Abstract. We use NAME, a trajectory model, to investigate the routes and timescales over which air parcels reach the tropical tropopause layer (TTL). Our aim is to assist the planning of aircraft campaigns focussed on improving knowledge of such transport. We investigate the conditions which might occur during one such campaign, SHIVA, which takes place in Borneo during November 2011. We first study the TTL above Borneo in November 2008, under neutral El Niño/Southern Oscillation (ENSO) conditions. Air parcels (trajectories) arriving in the lower TTL (below ~15 km) are most likely to have travelled from the boundary layer (BL; <1 km) above the West Pacific. Few air parcels found above ~16 km travelled from the BL in the previous 15 days. We then perform similar calculations for moderate El Niño (2006) and La Niña (2007) conditions and find year-to-year variability consistent with the phase of ENSO. Under El Niño conditions fewer air parcels travel from the BL to the TTL above Borneo. During the La Niña year, more air parcels travel from the BL to the mid and upper TTL (above ~15 km) than in the ENSO-neutral year, and again they do so from the BL above the West Pacific. We also find intra-month variability in all years, with day-to-day differences of up to an order of magnitude in the fraction of an idealised short-lived tracer travelling from the BL to the TTL above Borneo. Finally, we consider measurements made in two previous campaigns in order to validate our approach. The features of vertical profiles of short-lived species observed in the TTL during CR-AVE and TC4 are in broad agreement with calculated vertical profiles of idealised short-lived tracers. It will require large numbers of observations to fully describe the statistical distribution of short-lived species in the TTL. This modelling approach should prove valuable in planning flights for the long-duration aircraft capable of making such measurements.
On the uses of a new linear scheme for stratospheric methane in global models: water source, transport tracer and radiative forcing
Authors: Monge-Sanz B. M. , Chipperfield M. P. , Untch A. , Morcrette J.-J. , Rap A. , Simmons A. J.
Published: January 2012

Abstract. A new linear parameterisation for stratospheric methane (CoMeCAT) has been developed and tested. The scheme is derived from a 3-D full chemistry transport model (CTM) and tested within the same chemistry model itself, as well as in an independent general circulation model (GCM). The new CH4/H2O scheme is suitable for any global model and here is shown to provide realistic profiles in the 3-D TOMCAT/SLIMCAT CTM and in the ECMWF (European Centre for Medium-Range Weather Forecasts) GCM. Simulation results from the new stratospheric scheme are in good agreement with the full-chemistry CTM CH4 field and with observations from the Halogen Occultation Experiment (HALOE). The CH4 scheme has also been used to derive a source for stratospheric water. Stratospheric water increments obtained in this way within the CTM produce vertical and latitudinal H2O variation in fair agreement with satellite observations. Stratospheric H2O distributions in the ECMWF GCM present realistic overall features although concentrations are lower than in the CTM run (up to 0.5 ppmv lower above 10 hPa). The potential of the new CoMeCAT scheme for evaluating long-term transport within the ECMWF model is exploited to assess the impacts of nudging the free running GCM to ERA-40 and ERA-Interim reanalyses. In this case, the nudged GCM shows similar transport patterns to the CTM forced by the corresponding reanalysis data, ERA-Interim producing better results than ERA-40. The impact that the new methane description has in the GCM radiation scheme is also explored. Compared to the default CH4 climatology used by the ECMWF model, CoMeCAT produces up to 2 K cooling in the tropical lower stratosphere. The effect of using the CoMeCAT scheme for radiative forcing (RF) calculations has been investigated using the off-line Edwards-Slingo (E-S) radiative transfer model. Compared to the use of a tropospheric global 3-D CH4 value, the CoMeCAT distributions produce an overall decrease in the annual mean net RF, with the largest decrease found over the Southern Hemisphere high latitudes. The effect of the new CH4 stratospheric distribution on these RF calculations is of up to 30 mW m−2, i.e. the same order of magnitude, and opposite sign, as the inclusion of aircraft contrails formation in the radiative model.
Sampling and analysis of chemical element concentration distribution in rock units and orebodies
Authors: Agterberg F. P.
Published: January 2012

Abstract. Existing sampling techniques applied within known orebodies, such as sampling along mining drifts, yield element concentration values for larger blocks of ore if they are extended into their surroundings. The resulting average concentration values have relatively small "extension variance". These techniques can be used for multifractal modeling as well as ore reserve estimation approaches. Geometric probability theory can aid in local spatial covariance modeling. It provides information about increase of variability of element concentration over short distances exceeding microscopic scale. In general, the local clustering of ore crystals results in small-scale variability known as the "nugget effect". Parameters to characterize spatial covariance estimated from ore samples subjected to chemical analysis for ore reserve estimation may not be valid at local scale because of the nugget effect. The novel method of local singularity mapping applied within orebodies provides new insights into the nature of the nugget effect. Within the Pulacayo orebody, Bolivia, local singularity for zinc is linearly related with logarithmically transformed concentration value. If there is a nugget effect, moving averages resulting from covariance models or estimated by other methods that have a smoothing effect, such as kriging, can be improved by incorporating local singularities indicating local element enrichment or depletion. Although there have been many successful applications of the multifractal binomial/p model, its application within the Pulacayo orebody results in inconsistencies, indicating some shortcomings of this relatively simple approach. Local singularity analysis and universal multifractal modeling are two promising new approaches to improve upon results obtained by commonly used geostatistical techniques and use of the binomial/p model. All methods in this paper are illustrated using a single example (118 Pulacayo zinc values), and several techniques are applied to other orebody datasets (Whalesback copper deposit, Witwatersrand goldfields and Black Cargo titanium deposit). Additionally, it is discussed that nugget effects exist in a binary series of alternating mostly gneiss and metabasite previously derived from KTB borehole velocity and lithology logs, and within a series of 2796 copper concentration values from this same drill-hole.
Statistical analysis of polychaete population density: dynamics of dominant species and scaling properties in relative abundance fluctuations
Authors: Quiroz-Martinez B. , Schmitt F. G. , Dauvin J.-C.
Published: January 2012

Abstract. We consider here the dynamics of two polychaete populations based on a 20 yr temporal benthic survey of two muddy fine sand communities in the Bay of Morlaix, Western English Channel. These populations display high temporal variability, which is analyzed here using scaling approaches. We find that population densities have heavy tailed probability density functions. We analyze the dynamics of relative species abundance in two different communities of polychaetes by estimating in a novel way a "mean square drift" coefficient which characterizes their fluctuations in relative abundance over time. We show the usefulness of using new tools to approach and model such highly variable population dynamics in marine ecosystems.
La Universidad desde una Perspectiva Cosmopolita
Authors: Kemp Peter
Published: January 2012

Le but de cet article est de montrer pourquoi les sciences humaines sont plus nécessaires que jamais dans le cadre de l'enseignement à l'Université dans notre âge cosmopolite contemporaine. Nous avons besoin des sciences humaines, si nos établissements d'enseignement sont engagé à surmonter les menaces de politiciens bornés et des exécutifs afin de réduire l'éducation dans les écoles et les universités à une simple instruction en gestion sans orientation des cultures du monde exprimée dans l'art et la littérature, la connaissance de langues, d'histoire et de la philosophie.  Par conséquent, j'utilise les travaux théoriques de Paul Ricœur par rapport aux institutions d’éducation justes et éthiques, comme point de départ de ces arguments.
Ricoeur, Rawls, and Capability Justice
Authors: Dauenhauer Bernard P.
Published: January 2012

A review of Molly Harkirat Mann, Ricoeur, Rawls, and Capability Justice (London and New York: Continuum Books, 2012), pp. 232.
O Problema do Fundamento da Moral
Authors: Ricœur Paul
Published: January 2012

None.