bluuebunny/crossref_metadata_2025 huggingface dataset:
A Kind of Network Intrusion Detection Method Using Improved Support Vector Machine Based on Ant Colony Algorithm
Authors: Zhang Xiaoqin , Jia Guo Jun
Published: December 2012

Support vector machine (SVM) is suitable for the classification problem which is of small sample, nonlinear, high dimension. SVM in data preprocessing phase, often use genetic algorithm for feature extraction, although it can improve the accuracy of classification. But in feature extraction stage the weak directivity of genetic algorithm impact the time and accuracy of the classification. The ant colony algorithm is used in genetic algorithm selection stage, which is better for the data pretreatment, so as to improve the classification speed and accuracy. The experiment in the KDD99 data set shows that this method is feasible.
A Survey on Malware Containment Models in Smartphones
Authors: Peng San Cheng
Published: December 2012

Smartphones providing services like SMS/MMS, emails, online banking, and other applications, are becoming an integral part of our everyday lives. However, the availability of these services and applications provided by smartphones makes them a target for malicious attackers to propagate malware and perform other malicious attacks. To restrain malware propagation, the research advancement of malware containment is summarized in this paper. We provide an overview on malware, which includes the evolution of mobile malware, related concept, infection vectors, and risks. The typical malware containment models are selected to discuss in detail. At last, the current problems and challenges in this field for future work are proposed. This paper indicates that diversity and complexity of mobile malware pose great challenges in modeling malware containment.
Study on AC Stray Current Corrosion Law of Buried Steel Pipelines
Authors: Wang Xin Hua , Yang Guo Yong , Huang Hai , Chen Zhenhua , Wang Li Mei
Published: December 2012

AC stray current can cause AC corrosion and destroy the safe operation of buried pipelines, which comes mainly from nearby high voltage transmission lines and AC electric railway. The research and evaluation lags far behind DC stray current at home and abroad, besides, the AC current density measuring procedures are complex. Through experimental study of different parameters on the impact of the AC current density established a mathematical model of damaged area, soil resistivity, pipe-to-soil potential and coating resistivity. With it can indirectly get the AC current density, which improve efficiency by simplifying the measuring procedures. Also, provide a basis for harmfulness evaluation of AC stray current by studying the impact of AC current density on the corrosion rate.
Research of Multi-Satellite TT&C Scheduling Problem
Authors: Ling Xiao Dong , Zhu Wei Kang , Wu Jin Mei , Wu Xiao Yue
Published: December 2012

Multi-Satellite TT&C Scheduling Problem（MuSTSP） is to the keypoint of help doing high level design for space TT&C network and the conflict is the most important thing which result in MuSTSP. In this paper, the conflict is aboratively analyzed. Some new conceptions are proposed. Then a new heuristic scheduling method based on conflict-resolvation is introduced. A simple example is given to elaborate the feasibility of this method.
A Dynamic Programming Control Strategy for HEV
Authors: Cezar Babici Leandru Corneliu , Alexandru Onea
Published: December 2012

Dynamic programming is a very powerful algorithmic paradigm which solves a problem by identifying subproblems and tackling them one by one. First the smallest are solved, and then using their answers, it can be figured out larger ones, until the whole lot of them is solved. This paper presents a control strategy for hybrid electric vehicles, based on the dynamic programming, applied in MATLAB, Simulink environment, using ADVISOR. It was tried this method due to the calculation speed of the suitable torque and speed required from the engine, considering the driver power request (torque and speed), and the state of charge (SOC) of the batteries. Using the fuel converter (FC) fuel map, and the remaining SOC of the battery pack, it was designed an algorithm that will chose at each time the required torque and speed from the first and second source of power.
An Active Capacitance Multiplier Based on Switched-Capacitor DC-DC Converter
Authors: Fu Hui Kai
Published: December 2012

A technique of replacing the floating capacitor by an active capacitance multiplier is proposed in this paper, in order to overcome the difficulty in fabrication of the large capacitors in monolithic integrated circuits. The simulation results show that the same output characteristics can be obtained from the new charge pump with a capacitor much smaller than that adopted in the normal charge pump products. Therefore, the new charge pump is much easier to be fabricated in fully integrated realizations with on-chip capacitor.
Sequential Beacon Scheduling Mechanism for Cluster-Tree WSNs
Authors: Su Hao Ru , Shi Zhi Guo , Wang Zhi Liang
Published: December 2012

To solve the beacon collision problem in IEEE 802.15.4/ZigBee cluster-tree Wireless Sensor Networks, we proposed a Sequential Beacon Scheduling (SBS) mechanism. In this mechanism, the Cluster Headers (CHs) choose the beacon transmission time in a certain order. The CH which finishes the sequence chosen sends out control frame to inform other CHs in its interference range. The simulation results indicate that SBS general has better delivery ratio, latency, and throughput than three other beacon scheduling mechanisms.
An Improved Algorithm of LEACH Routing Protocol Based on Energy-Balancing
Authors: Liu Guang Cong , Li Cong , Shi Yuan Jie
Published: December 2012

In order to balance energy consumption and save energy as the starting point, an algorithm of LEACH–GAE protocol based on energy balance is put forward for LEACH protocol improvement ,which combined with genetic algorithm and ant colony in view of the problem of LEACH in choosing its cluster head selection,cluster heads and base station communication deficiencies. The simulation results show that LEACH-GAE protocol can effectively balance the energy consumption and prolong the network life cycle.
Seismic Protection of Steel Frames Using Friction Damper Devices
Authors: Valente Marco
Published: December 2012

This study investigates a friction damping bracing system in order to improve the response of steel frames when subjected to severe seismic excitations, beyond the design earthquake. A simplified model describing the behavior of the friction damper device was developed for global analyses of steel frames. Parametric analyses based on numerical simulations were carried out to evaluate the slip force with the aim of minimizing the values of top displacement and hysteretic energy dissipated by the steel frame. The main results of nonlinear dynamic analyses performed on a six-story steel frame incorporating friction damping bracing systems are presented and compared with the response of the unprotected counterpart. The effectiveness of the protection system was also assessed by examining the seismic response of the frame equipped with traditional braces, without friction devices. The results of the numerical investigations showed that the use of the friction damping bracing system caused an increase of the dissipative capacity of the frame, above all for high seismic actions. The plastic deformation concentrated inside the device, protecting the main structural elements from severe damage. The formation of the plastic hinges at the column base was delayed with respect to the unprotected frame. Numerical analyses indicated that the introduction of supplemental damping by using friction devices in steel bracings is very effective for seismic protection of steel frames subjected to severe seismic excitations.
Theoretical Study of Energy-Level Splitting of Cs2NaPrCl6 Crystal
Authors: Duan Mei Ling , Li Jin Hong , Yang Xiao Feng
Published: December 2012

The 91×91 complete energy matrix of 4f2 configuration ion Pr3+ in octahedral cubic crystal field has been constructed based upon the combination of Racah’s group-theoretical consideration with Slater’s wavefunctions. The energy levels of the neat hexachloride elpasolite crystals Cs2NaPrCl6 containing rare earth Pr3+ ion have been calculated. The results imply that the diagonalization to the complete energy matrix can be received as an effective method of performing a theoretical calculation to the rare earth compounds.
Effect of Deposited Angle on Structure and Surface Morphology of Fluorocarbon Films Deposited by Pulsed Plasma Thruster
Authors: Zhang Rui , Wu Jian Jun , Zhang Dai Xian , Zhang Fan , He Zhen
Published: December 2012

A series of fluorocarbon films were deposited on glass substrates by Pulsed Plasma Thruster. The effects of deposited angle on chemical structure and surface morphology of these films were investigated using X-ray photoelectron spectroscopy (XPS) and scanning probe microscope (SPM). XPS data imply various carbon-related chemical components present on the surface of the deposited films are strongly impacted by the deposited angle. AFM measurements show that the increase in deposited angle can smoothen the surface morphology and decrease the RMS roughness. Changes in density of the neutral particle and flux of ions that reach the surface affect the formation of fluorocarbon clusters in the films and reduce surface roughness.
Variable Separation Solutions for the (2+1)-Dimensional General Ablowitz-Kaup-Newell-Segur Equation
Authors: Lei Jun , Ma Song Hua , Fang Jian Ping
Published: December 2012

With the help of the symbolic computation system Maple and the Riccati equation projective approach and a linear variable separation approach, a new family of the variable separation solutions of the (2+1)-dimensional general Ablowitz-Kaup-Newell-Segur(GAKNS) equation is derived. Based on the derived solitary wave solution, we obtain some line-soliton localized excitations.
Review on the Development of the Accessory Rotary Ultrasonic Machining Tools
Authors: Zhu Xue Ming , Lin Bin , Liu Li Ping
Published: December 2012

Rotary ultrasonic machining(RUM) as a precise and efficient processing method for hard and brittle materials can be used for significantly improving processing efficiency, reducing the cutting force and cutting heat, improving the surface quality. Development of high performance RUM machine tools and equipments has been caused on widespread attention from the worldwide scholars. In this paper, the development of the RUM machine tools has been reviewed about the accessory RUM head and load matching system.
Design of Intelligent Guide Vehicle for Blind People
Authors: Xu Xiao Wen , He Jin Yi
Published: December 2012

Traditionally, guide dogs are used as a travel aid for blind people. But they cannot be popularized because the training cost for guide dogs is quite high. This paper presents an intelligent guide vehicle prototype for blind people. The system is developed by using ARM as a controller and processor, via integration of ultrasonic detection and photoelectric detection technology, aiming at automatically navigation for blind people. This system mainly consists of four modules, which are ultrasonic detection module, photoelectric detection module, voice prompt module and automatic control module. The signal reflected by roadblock on the road can be detected by ultrasonic detection module which can work out distance between roadblock and guide vehicle. The aim of photoelectric detection module is to realize the function of road recognition and tracking. Voice prompt module can provide information of distance of roadblock. Strategies of obstacle avoidance were taken to the blind when the guide vehicle is going to avoid roadblock. If the roadblock is less than 50cm away, the automatic control module will automatically set the guide vehicle to avoid obstacles. Preliminary experimental results show that users can control and navigate with the intelligent guide vehicle.
Padé Approximation Method for FDTD Modeling of Wave Propagation in Dispersive Media
Authors: Chen Wei
Published: December 2012

A finite-difference time-domain (FDTD) method for simulating wave propagation in Cole-Cole dispersive media was presented. The main difficulty of the proposed way was the appearance of fractional time derivatives in the FDTD equation. The Padé approximation method was employed to solve this problem. The expansion of the fractional time derivatives could deal with this model. The comparison of analytical and calculated the reflection of a plasma proves the validity of the method. Then apply this method to calculate the reflection of the air-muscle interface.
The Study of Infrared Photocarrier Radiometry Based on Si Semiconductor
Authors: Qin Lei , Liu Jun Yan , Wang Yang
Published: December 2012

Infrared photocarrier radiometry(PCR) has shown advantages of pure detection signal, bigger detection depth and more clear results since it emerges. But it is still in the starting stage. Generation and distribution of photocarrier excitated by modulated laser is stated, and the principle of PCR is discussed. Experiment on different sweeping frequencies is carried out and frequent characteristics are studied.The principle and experimental results are compared with PTR .The results show the most fit modulated frequency of PCR is around 10kHz, and the differences between the defect and non-defect area is bigger than that of PTR.
CdSe/ZnO Core/Shell Semiconductor Nanocrystals: Synthesis and Characterization
Authors: An Li Min , Chen Xuan Lin , Han Xue Ting , Yi Jie , Liu Chun Xia , An Wen Yu , Qu Yu Qiu , Chi Jian Guang , Wei Hong , Qi Kai Yue , Wen Ya Nan , Wang Qiang , Zhou Wei Gang , Ye Hong An , Sun Zhuo
Published: December 2012

CdSe/ZnO core/shell semiconductor nanocrystals which show high luminescence quantum yield have been synthesized through a simple routine without the use of any pyrophoric organometallic precursors. Transmission electron microscope image demonstrates the shape, monodispersity, average size, size distribution and core-shell structure of CdSe/ZnO nanocrystals. We use a combination of X-ray diffraction, UV-Vis absorption spectroscopy and photoluminescence to analyze the core/shell nanocrystals and determine their chemical composition, optical character and internal structure.
Study of the Initial Well Production Line of Adjusted Wells in X Oilfield
Authors: Yuan Zhang , Fan Hong Fu , Liu Hong Xia , Wang Shuo Liang
Published: December 2012

Different overseas oil field development and production projects, have different tax provisions. The contract requires different models for different development strategies. In this paper, the X oilfield abroad, for example, studied the oilfield development to adjust the initial well production line, and the adjustment of the oil field development well later provided the basis for the deployment.
The Role of Copper in the Growth of Methylosinus trichosporium IMV 3011 and Poly-β-Hydroxybutyrate Biosynthesis
Authors: Dong Jing
Published: December 2012

Methanotrophs are aerobic microorganisms that utilize methane as substrates for growth and PHB Biosynthesis. Copper plays an important role in cell growth and PHB biosynthesis. The effect of initial copper concentration on cultivation of M. trichosporium IMV 3011 on methane was investigated. With the addition of 30μmol/L CuSO4•5H2O, PMMO activity improved to 4 times of that without copper addition. The highest density of cultivated cells is 0.48g dry wtL-1, which is 2 times of that without copper addition. The lag time shortened to 15.87h, and the growth rate increased to 0.082h-1.The PHB content increased to 8.3%. It is found that certain initial copper concentration is beneficial to expression of high particulate methane monooxygenase activity, which may contribute to the synthesis of PHB in the cell.
Anisotropy Affecting Dendrite Growth of Fe-C Alloy in a Forced Flow
Authors: Yuan Xun Feng , Liu Bao Ying
Published: December 2012

The phase-field model coupling with the concentration field and flow field was used to simulate the dendrite growth during isothermal solidification of Fe-C alloy in a forced flow. The effects of anisotropy modulus and anisotropy strength on the dendrite growth are studied. The results indicate that the dendrites have four preferential growth orientation and the side-branches growth is not perpendicular to the primary branch while the dendrite along with crystallographic directions. When the dendrite along with crystallographic directions, the dendrites have six preferential growth orientation and the side-branches are parallel to the neighborly primary branch. At a anisotropy strength of 0.01, the crystal have no apparent principal branch and grows into coral shapes.With an increase in anisotropy strength, the tip solute concentration decreases, makes the dendrite growth become fast, the tip velocity increased continuously.
Modeling and Experiment of the Cutting Force for Aluminium Alloy Work-Piece
Authors: Wang Mu Lan , Hou Jun Ming , Wang Bao Sheng , Ding Wen Zheng
Published: December 2012

The application of Finite Element Method (FEM) in cutting force model for Aluminium alloy work-piece is useful to reduce the production costs and shorten the experimental period. Firstly, the theoretical model of the orthogonal cutting and the oblique cutting are analyzed in this paper. And then, the corresponding finite element models are theoretically constructed. By comparing the results, the following conclusions are drawn: with the increase of the cutting thickness, the cutting force increasing is in an enhancement tendency. The oblique cutting model of overall tool is more conductive to the subsequent runout and the flutter analysis.
Numerical Simulations of Combustion and Decomposition Processes in Precalciner with Two Different Heights of Raw Meal Inlets
Authors: Mei Shu Xia , Xie Jun Lin , He Feng , Jin Ming Fang
Published: December 2012

To reduce energy consumption, numerical simulations of combustion and decomposition processes in a precalciner were carried out with two different heights of raw meal inlets. In Euler coordinate system the gas phase is expressed with k-ε two-equation model, in Lagrange coordinate system the solid phase is expressed with discrete phase model (DPM), the chemical reaction is expressed with species transport model, and the radiation is expressed with P1 radiation model. The results show that when the raw meal inlets are near the jetting coal pipes, there is much better dispersing condition of CaCO3 but a much poorer coal combustion condition, resulting in a much higher CaCO3 decomposition rate but a lower coal burn-off rate than that when the raw meal inlets are far away from the jetting coal pipes. It is advised to install both the two heights of raw meal inlets in order to obtain not only high CaCO3 decomposition rate but also high coal burn-off rate.
Multi-Objective Optimization Design of Hard Gear-Face Point-Line Meshing Gear
Authors: Huang Hai , Qin Yin Yi , Tao De Xin , Long Hong Xin
Published: December 2012

In order to improve efficiency of designing point-line meshing gears further, goal programming is used in point-line meshing gear optimization design. Optimization goals are the actual bending fatigue strength safety coefficient, the actual contact fatigue strength safety coefficient and composite stiffness of point-line meshing gear and the optimization mathematical model is established. A example is used to verify the method.
Measuring Data Registration Based on Triangle Constraint
Authors: Ye Tie Li , Li Xue Yi , Zeng Qing Liang
Published: December 2012

This paper studied the fine registration techniques of measuring data of complex product and proposed a new registration method based on triangle constraint. Firstly, the paper made a research on specifying the proper measuring reference points and the setting of reference coordinate system, and afterwards proposed a fine registration algorithm of measuring data, Which is about realizing the fusion of reference coordinate system based on the congruent judgment of reference triangle and fulfilling precise match of data with measuring error on the basis of controlling the rotation of data blocks and minimizing the registration error.
Study on the Stray Light Suppression of Fundus Camera
Authors: Wang Jing Yi , Chen Yan Wu
Published: December 2012

Fundus camera is a system that is a kind of observation and records the images of the retina of the eye. Through these retinal images, it can diagnosis Systemic diseases early, but Stray light will make the images blur and contrast reduction, reduce the ratio of Signal to noise of the images, affect the fundus camera imaging quality seriously, we must eliminate it. In this paper, aiming at the fundus camera stray light sources that gives the corresponding stray light suppression measures, for the fundus camera’s further developments provide a reference, prospecting the future technology development of eliminating stray light.
Effect of Foaming Agent on Microcellular Unsaturated Polyester
Authors: Zhao Xue Ni , He Jian Peng , Zhai Pei Pei , Ren Wei
Published: December 2012

Microcellular unsaturated polyester was prepared by different foaming agents was studied. Compared with the cell size and density of microcellular unsaturated polyester prepared using azodicarbonamide (AC), the ones of microcellular unsaturated polyester prepared using NaHCO3 were small. For NaHCO3, the cell density of microcellular unsaturated polyester decreased with the increasing temperature. For microcellular unsaturated polyester prepared using NaHCO3 at 100 °C, the average cell size was about 18 μm and the cell density was 1.1×1010 cells/cm3. The compression strength at 100 °C is strongest among that of the materials at the other temperature. The average compression strength was 24.2 MPa. The compression strength-to-weight ratio of microcellular unsaturated polyester prepared at 90 °C and 100 °Cwas about twice that of unsaturated polyester.
Densification of MnZn Ferrite Sintered under Multi-Physical Field Coupling
Authors: Du An Kang , Yang Gang , Lu Dong , Qin Yi , Yang Yi
Published: December 2012

This work provides a novel idea of fabricating MnZn bulk ferrite materials. MnZn ferrite powders with a composition of Zn0.8Mn0.2Fe2O4 (wt%) are sintered to form cylindrical bulk ferrite with diameters of 1.0mm, and heights of 1.0mm under multi-physical field coupling with Gleeble-1500D thermal simulation instrument. The results show that sintered ferrite has a spinel structure, and that some magnetic properties like maximum energy product and remanence of the Multi-physical Field Coupling sintered sample are better than that obtained by conventional sintering. Densification process and solid phase reaction are promoted by alternating magnetic field and high frequency wave generated by AC current.
Optimization Model of Metal Rubber Buffer on Artillery
Authors: Ning Sheng Ke , Jia Luo , Ma Bao Ji
Published: December 2012

This article describes optimization mathematical model of metal rubber buffer on artillery. In this paper, motion equation of new metal rubber buffer on artillery, stiffness model of the ring spring, constitutive relation of metal rubber, and mathematical model of friction block are constructed. According to the technical requirements of buffer, optimization variables, constraints, and object function are identified. Then optimization mathematical model is established.
Two Kinds of Cold Working Steel Performance Contrast Research
Authors: Gao Bing , Wang B.
Published: December 2012

In project practice, Anchor ability of coupled steel bars concrete will higher than cold rolling belt rib steel bars. So, more economical steel bars and cement contents. Through comparative trial about on concretes component of coupled steels bars and cold rolling belt rib steel bars in this article. Summarizes that anchor ability of Low-alloy coupled steels are depending transverse steel, well, steel bars and concretes has the better joint work ability.
Test Investigation on Stiffness Performance of Steel Structures Composed of Cold-Roller-Bent Pipes
Authors: Sun Wen Bo , Zhou Wei Jian
Published: December 2012

Curve-shaped roofs and facades are popularly used in the construction with roller bent pipe, which serves as structural element. Roller bent pipe are manufactured from straight pipe by a process called roller bending. The material is cold worked during forming, inducing a new distribution of mechanical properties across the section which is different compared to its original state. For a long time, original mechanical properties of the straight material are used in the design of curved structure. The influence of the roller bending process is usually ignored non-conservatively. Theoretically, cold-working makes the strength increased while the modulus decreased. The results of a series of tests and measuring investigation of the mechanical properties of cold-roller-bent pipes are present in this paper. The decreased modulus of cold-roller-bent pipes have significantly softened and weakened the overall mechanical properties of structures. The influence should be considered in the design of structures composed of cold-roller-bent pipes.
Based on Imitation Seagull Airfoil UVA Wing Numerical Simulation
Authors: Hua Xin , Shao Wei , Zhang Chun Hua , Zhang Zhi Qiang
Published: December 2012

Wing aircraft is one of the major components to generate lift, in today's energy shortage, design the high lift-to-drag ratio wing is the goal pursued by, The author in the exploration of bionic airfoil aerodynamic characteristics on the basis of, which will be applied to straight wing design so as to improve the aerodynamic performance of aircraft.Our research mainly includes two aspects: first, the use of imitation seagull airfoil and NACA4412 airfoil are designed into the straight wing. The use of FLUENT software in Re=300000condition carries on the numerical simulation results show that the ratio of gull wing airfoil than NACA4412 lift coefficient increased by 13%, while the lift to drag ratio,is improved by 46.83%. Then, using the similarity principle, the wing scale, was tested in a wind tunnel test, the results obtained with the simulation are consistent. Airfoil design for the design of high performance wing opened a new way.
Discussion of Energy and Automobile Styling
Authors: Guan Jia Zheng
Published: December 2012

The energy gradually become the mainstream of the development of the new century automobile. Worsen environmental problems and increases nervous energy issues forcing people to continue to seek a clean alternative fuels, in order to improve the traffic situation. Energy to become the focus of attention of Governments and car manufacturers. People have spared no effort to carry out energy vehicles.
Phosphate Removal from Aqueous Solution Using Fly Ash Modified with Magnetic Fe-Zn Bimetal Oxide
Authors: Xu Ke , Deng Tong , Li Chun Guang , Niu Jun Ling
Published: December 2012

In this work the adsorption of phosphate using the magnetic Fe-Zn bimetal oxide modified fly ash was studied. The experimental results showed that the effective pH range for the adsorption of phosphate was between 3.0 and 9.0. The removal percentage of phosphate reached maximum at pH 8.0. Kinetic study showed that the phosphate adsorption was well described by pseudo second order model. The removal efficiency of phosphate increased with the increase of adsorbent dosage and the decrease of the initial concentration. The adsorption of phosphate could be described well by Langmuir isotherm, the Langmuir constant Q0 was 24.15mg/g.
An Overview of Maximum Power Point Tracking Techniques for Wind Energy Conversion Systems
Authors: Meenakshi Ram , Muthu Ranganath
Published: December 2012

This paper presents on overview of maximum power point tracking (MPPT) techniques for different types of wind energy conversion systems (WECS). In order to obtain maximum power from the wind turbine (WT), variable speed wind energy conversion systems (VSWECSs) are preferred over constant speed wind energy conversion systems (CSWECSs).In VSWECS, the rotational speed of the turbine is varied by controlling the aerodynamic or electrical parameters of WECS to maintain a constant tip-speed ratio (TSR). This is called maximum power point tracking and different techniques are applied to WECS namely Squirrel Cage Induction Generators (SCIGs) based WECS, Permanent Magnet Synchronous Generators (PMSGs) based WECS.
Maturity Evolution of the Cambrian Source Rocks in the Tarim Basin
Authors: Xiao Zong Lin , Hao Qing Qing , Shen Zhong Min
Published: December 2012

The Tarim basin is an important petroleum basin in China, and the Cambrian strata are the major source rock successions in the basin. Integrated the source rock depositional and structural history with its geochemical and thermal parameters, this paper simulates the evolution of the Cambrian source rocks with the software Basinview. The simulation result shows that the main hydrocarbon-generation centers of the Manjiaer sag in the Tabei depression and the Tangguzibasi sag in the Southwest depression are characterized by their early hydrocarbon generation, and in the late Ordovician depositional age, they reached dry gas stage. The Kuqa and Southwest depressions developed in the Cenozoic foreland basins made the Cambrian source rocks mature rapidly in the Cenozoic period. The source rock maturity in the Tarim basin now is characterized by high in the east and west and low in the middle, and most of the area is in the over-mature stage in the present. This study can provide available maturity data for the next petroleum exploration work.
Advance Two-Area Load Frequency Control Using Particle Swarm Optimization Scaled Fuzzy Logic
Authors: Jaber Aqeel S. , Ahmad Abu Zaharin B. , Abdalla Ahmed N.
Published: December 2012

One of the most important rules in electric power system operation and control is Load Frequency Controller (LFC). Many problems are subject to LFC such as a generating unit is suddenly disconnected by the protection equipment and suddenly large load is connected or disconnected. The frequency gets deviated from nominal value when the real power balance is harmed due to disturbances.LFC is responsible for load balancing and restoring the natural frequency to its natural position. In this paper, PSO-fuzzy logic technique for Load Frequency Control system was proposed. PSO optimization method is used to tuning the input and output gains for the fuzzy controller. The proposed method has been tested on two symmetrical thermal areas of an interconnected electrical power system. The simulation results are carried out in term of effectiveness of the frequency time response on its damping and compared it to common PID controller. The results show the performances of the proposed controller have quite promising compared to PID controller.
Development of Dense Hydroxyapatite Nanoceramic by Pressureless Sintering
Authors: Punyanitya Sittiporn , Raksudjarit Anirut
Published: December 2012

In order to improve fracture toughness, nanocrystalline hydroxyapatite (HA) powder was used for fabricate dense HA nanoceramic. The nanocrystalline HA powder was obtained with ball milling for 12 h from calcined natural bovine bone. The green compacts of HA nanopowder were sintered by pressureless sintering with non-linear heating rate sintering at 1200°C for 3 h. Fracture toughness and hardness properties of HA nanoceramic have been assessed using indentation technique. The fracture toughness values of sintered nanosized-HA powder is 3.50.1 MPa.m1/2, which is within those of human cortical bone. The nanostructure with liquid phase sintering of sintered nanosized-HA powder contributed to the increase of fracture toughness. The toughening mechanisms of pull-out of nanocrystalline HA and grain boundary sliding have been observed.
First-Principles Study of Electronic Structure and Elastic Properties of Si Doping Ti3Al1-xSixC2 Solid Solutions
Authors: Zeng Fan Jun , Xia Qing Lin
Published: December 2012

The electronic structure and elastic properties of Si doping Ti3Al1-xSixC2 (x=0-1) were studied by generalized gradient approximation (GGA) based on density functional theory (DFT) and virtual crystal approximation (VCA). The calculated lattice parameters and equilibrium volumes are in good agreement with the available experimental data. The density of state (DOS) shows that the DOS at the Fermi level (EF) is located at the bottom of a valley. Single-crystal elastic constants were calculated and the polycrystalline elastic modules were estimated according to Voigt, Reuss and Hill’s approximations (VRH). The results show that the bulk modules increase monotonously and the Poisson ratio v as well as BH and BG increase first and then decrease with the increasing of the doping Si. The Passion ratio v and BH/GH indicate that Ti3Al1-xSixC2 (x=0-1) are brittle compounds. Polycrystalline elastic anisotropy coefficients AB and AG were also derived and are very small.
Solution Phase Synthesis of Amorphous Carbon Nanoparticles under Ambient Atmosphere
Authors: Liu Bo Yang , Zhou Yun , Dong Li Hua , Yin Yan Sheng
Published: December 2012

A novel solution-phase method is developed for preparation of amorphous carbon nanoparticles with high specific surface area under ambient atmosphere by the reaction of ferrocene and ammonium chloride in polyethylene glycol 400 (PEG 400) at 200 oC. Samples are characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (SEM), transmission electron microscopy (TEM) and N2 adsorption-desorption isotherms. It is found that the nanoparticles are complete amorphous and agglomerate together due to the strong surface tension. The amorphous carbon nanoparticles with a diameter of 40-100 nm have a wide size distribution of mesopores with a Brunauer-Emmett-Teller (BET) surface area of 402.28m2•g-1. It is proposed that the dissolved reactants uniformly dispersing in the solutions could react at a molecular level to form uniform carbon nanoparticles.
Electronic Structure and Optical Properties of SiC Nanotube Material with Silicon Antisite Defect
Authors: Li Ke Jian , Song Jiu Xu , Liu Hong Xia
Published: December 2012

Based on first-principle calculations, electronic structure and optical properties of a single-walled zigzag SiC nanotube with silicon antisite defect have been investigated. This defect results in the formation of a bump in the surface of the nanotube. No defect energy level is formed in its band gap, which is originated from the resonance between the defect level and conduction band resulting in the defect level entering its conduction band. The most primary dielectric peak in dielectric function parallel to the axis of the nanotube is depressed, while the first peak perpendicular to its axis is enhanced. These results are meaningful for investigations on SiCNT electronic and optical devices.
Numerical Simulation of Water Removal Process in the Microstructure of Gas Diffusion Layer with Mechanics Properties and Material Properties
Authors: Sun Chao , Du Qing , Yin Yan , Jia Bin
Published: December 2012

The performance of proton exchange membrane fuel cell is greatly influenced by the presence, distribution and transport of liquid water in the gas diffusion layer (GDL). In this study, air-water flow in a 3D GDL microstructure along the in-plane direction is studied numerically by using the volume of fluid (VOF) method. The GDL microstructure is considered initially filled with water, air flows into the structure under the driving force of a set pressure drop and the flow is supported by the capillary pressure due to the hydrophobic nature of the GDL structure. It is found that water removal can be accelerated by improving pressure drop. Pressure drop has little influence on the state-steady water volume fraction when the pressure drop is over a critical value.
Effects of the Launch Speed on Hydrodynamic Force of the Underwater Vehicle Vertical Launch with the Gas Curtain
Authors: Liu Hai Jun , Peng Xing Zhi , Zou Zhen Zhu
Published: December 2012

The vertical launch of the gas curtain is a new underwater launch technology. The gravity effect of the launch speed on hydrodynamic characteristics of the underwater vehicle vertical launching by using the gas curtain has been studied by adopting the multiphase VOF model and the standardturbulence model. The relationship between the launch speed and the shape of the underwater vehicle has been achieved by using the numerical simulation. The relationships between the launch speed and the hydrodynamic characteristics of the underwater vehicle vertically launching from the tube, navigating in water and exiting water have been investigated by using numerical simulation. The hydrodynamic characteristics of underwater vehicle vertical launching by using the gas curtain method are small. The effects of the launch speed on the hydrodynamic characteristics of the underwater vehicle vertical launching in the gas curtain are small.
Dimensional Effect on DIBL in Silicon Nanowire Transistors
Authors: Hashim Yasir , Sidek Othman
Published: December 2012

Drain-induced barrier lowering (DIBL) is crucial in many applications of silicon nanowire transistors. This paper determined the effect of the dimensions of nanowires on DIBL. The MuGFET simulation tool was used to investigate the characteristics of the transistors. The transfer characteristics of transistors with different dimensions were simulated. The results show that longer nanowires with smaller diameters and lower oxide thickness decrease DIBL and tend to possess the best transistor characteristics.
Application of Biological-Based Antifungal Agent for Controlling the Growth of Wood Decaying Fungi of Rubberwood
Authors: Peng Teoh Yi , Don Mashitah Mat
Published: December 2012

Rubberwood played a crucial role in industries development in Malaysia, particularly in furniture sector. Preservative of rubberwood becomes important tool in order to obtain an environmental friendly antifungal agent. Thus, biological-based control agent was an alternative way to solve this issue. This study was conducted on the bio-production of antifungal agent towards the growth of wood decaying fungi of rubberwood. Schizohpyllum commune had reported to product schizophyllan during secondary metabolites, in which could possed antimicrobial activity. Batch solvent extraction using three solvent systems was carried out. After hydrodistillation process for 48 h, the results showed that 70% (v/v) methanol-water system provided the maximal extraction yield (41.47 %) for S. commune mycelia. The extracted antifungal agent had applied on the rubberwood block to investigate its effectiveness. The result found that the concentration at 5 μg/μl could inhibit the growth of white-rot fungi, in which was similar to that observed using minimum inhibitory concentration (MIC) assay previously.
Photocatalytic Activity under UV of TiO2 Powders Compared with Commercial P25
Authors: Sangchay Weerachai
Published: December 2012

TiO2 powders were prepared by sol-gel method. The prepared powders were synthesized at the temperature of 500 °C to 700 °C for 2 h with a heating rate of 10 °C/min. The characterizations of synthesized powders were characterized by XRD and SEM. Finally, photocatalytic activity was evaluated by UV-vis spectrophotometer compared with commercial P25. The results show all samples have the agglomeration. It was found that the effect of calcinations temperature on phase transformation, crystallite size, morphology and photocatalytic activity of the synthesized powders. It can be note that TiO2 powders show highes of photocatalytic activity more than P25 and calcined at 700 °C were found to give the highest photocatalytic efficiency (82%) under UV irradiation 6 h.
The Influence of AlkaliTreatment and Compatibilizer Addition on the Tensile Properties and Water Absorption Behavior of Polypropylene/Kenaf Fiber Composites
Authors: Taib Razaina Mat , Khairuddin Nurul Mujahidah Ahmad , Ishak Zainal Arifin Mohd
Published: December 2012

Composites of polypropylene (PP) and kenaf fiber (KF) were immersed in water at room temperature. The fiber was treated with alkaline solution. A compatibilizer, maleic anhydride-grafted polypropylene (MAPP) was added in some composite formulations. Composite with alkali treated fibers (KFA) showed similar tensile strength but lower tensile modulus than the composite with untreated fiber, KF. Addition of MAPP was crucial to improve the tensile properties and water resistance of either PP/KF or PP/KFA composites. Alkali treatment adversely affected the water absorption behavior of PP/KF composite.
Preparation of Natural Rubber/Sodium Montmorillonite Nanocomposites by Latex Mixing Method with Drying Process
Authors: Sookyung U. , Nakason Charoen , Thaijaroen W.
Published: December 2012

Natural rubber/sodium montmorillonite nanocomposites were prepared by using natural rubber latex without using acid coagulation. Cure characterization indicated that Na-MMT retarded the vulcanization reaction of NR. The mechanical properties of the NR/Na-MMT nanocomposites were improved with addition of Na-MMT which is attributed to the reinforcing effect of Na-MMT with rubber. Furthermore, the storage modulus (E) of the nanocomposites was higher than that of the pure NR vulcanizate. Furthermore, glass transition temperature (Tg) was shifted to higher temperature and lower Tan δ value was observed upon increasing loading levels of Na-MMT. Moreover, the nanocomposite showed higher thermal stability than that of the pure NR vulcanizate.
Feasibility of Producing Wood Fibre-Reinforced Geopolymer Composites (WFRGC)
Authors: Al Bakri Abdullah Mohd Mustafa , Izzat Ahmad Mohd , Muhammad Faheem M.T. , Kamarudin H. , Khairul Nizar I. , Bnhussain M. , Rafiza A.R. , Zarina Yahya , Liyana J.
Published: December 2012

Wood fibres have long been known as a fibre reinforcement for concrete. Due to its availability and low production cost, this natural fibre has been used in less developed country where conventional construction materials were very expensive. In Japan, the production of these types of composites such as high performance fibre-reinforced cement-based composite (HPFRCB), ultra high performance (UHPFRCB) and strain-hardening (SHCC) fibre-reinforced cement-based composite has been developed rapidly in last decades. Geopolymer, future composite and cement produced by the alkali-activation reaction is well known as a potential replacement to Ordinary Portland Cement. This study aims at studying the possibility to produce wood fibre-reinforced geopolymer composite (WFRGC). The various percentage of fibre have been made from 10% to 50% and cured at 60C, tested for compressive strength for 7th and 14th day and the microstructure examined using SEM. The density and water absorption test have been performed. The results showed are encouraging and indicate the feasibility of producing a wood fibre-reinforced geopolymer composite (WFRGC).
Classification of Damage Mode of Reinforced Concrete Beams Using Acoustic Emission Technique
Authors: Noorsuhada Md Noor , Azmi Ibrahim , Bunnori Norazura Muhamad , Soffian Noor Mat Saliah , Hamidah Mohd Saman , Shahiron Shahidan
Published: December 2012

Classification of damage modes in reinforced concrete (RC) beams was studied. Acoustic emission (AE) monitoring in conjunction with static test was applied on RC beams. The damage modes were classified by based on the load-deflection curve, the relationship between load and damage modes and the intensity analysis. It can be concluded that six damage modes were identified; namely micro-cracking, localized crack propagation, flexural crack distribution, shear crack formation, damage localization and failure of the beam. The use of intensity chart clearly estimates the zones of the damage mode of the reinforced concrete beams.
Design of a Novel Temperature Self-Operating Protective Clothing Based on Phase Change Material
Authors: Liu Tai Qi , Ma Fu Rui , Shi Qi Song , Chu Jin Fang , Li Tan Qiu , Yang Dong Hui
Published: December 2012

The clothing containing phase change material (PCM) with function of absorbing the body-released heat has wide applications. In this paper, a novel protective clothing based phase change material was investigated. The results show that PCM has suitable melting temperature, large heat flow, stability after repeating applications, and it is convenient for application in cooling. Moreover, the manufacturing process has a great affect on the property of the titled material. The above inorganic composite was selected to prepare the temperature self-operating protective clothing, which can efficiently lighten the demic thermal stresses at high and low temperatures.
Effects of Cryogenic Treatment on Mechanical Properties and Corrosion Resistance of LC4 Aluminum Alloy
Authors: Zhang Wen Da , Yang Jing , Dang Jing Zhi , Liu Yun , Xu Hong
Published: December 2012

The hardness, compressive strength and corrosion rates of LC4 aluminum alloy in 3.5% NaCl solution before and after cryogenic treatment were measured. The microstructure, mechanical properties after cryogenic treatment and corrosion resistance of LC4 aluminum alloy were investigated. The results show that cryogenic treatment can enhance the hardness of annealed LC4 aluminum alloy. An aging treatment at 120 °C for 24 h after cryogenic treatment yielded corrosion-resistant LC4 aluminum alloy with better mechanical properties.
Fabrication, Tensile and Bending Properties of Wheat Straw/Polylactic Acid Green Composites
Authors: Wu Li Ying , Xu Fu Jun , Zhao Peng Wei , Qiu Yi Ping
Published: December 2012

Polylactic Acid (PLA) and raw Wheat Straw (WS) were used to fabricate WS/PLA green composites. By hot-press process, WS/PLA composites with different WS volume fractions (20% and 30%) were obtained. The experimental results showed that when the WS volume fraction was 20%, the composites had a tensile strength of 23.68MPa and modulus of 1.47GPa; bending strength of 64.13MPa and modulus of 1.44GPa. When the WS volume fraction increased to 30%, the tensile strength and modulus enhanced by 45.18% and 35.37% respectively; bending strength and modulus increased by 15.80% and 25.69%. It was indicated that PLA can be successfully reinforced by WS at certain volume fractions.
The Effect of Calcium Chloride on Polyamide 6 Electrospun Fibers
Authors: Wei Wei , Yeh Jen Taut , Qiu Liang
Published: December 2012

The effects of calcium chloride (CaCl2) on polyamide 6 (PA6) electrospun fibers were investigated on this study. The interaction between CaCl2 and PA6 could affect the crystaline of PA6. XRD, DSC and FTIR revealed that the crystaline of PA6 reduced with increasing CaCl2. Moreover, the addition of CaCl2 could modify PA6 spinning solution properties, i.e., conductivity, surface tension and viscosity. The interaction between CaCl2 and PA6 has an important influence on morphological appearance and sizes of the resulting PA6 electrospun fibers.
Effect of the Nucleating Agent BN on Crystallization Properties of P(3HB-co-4HB)
Authors: Sun Bing Xin , Feng Xu Qiao , Chuai Cheng Zhi , Guo Ying , Luo Si
Published: December 2012

The crystallization properties of P(3HB-co-4HB) modified with nucleating agent BN was studied. DSC is used to analyze the melting crystallization behavior and POM is used to characterize crystal structure and morphology. The results show the incorporation of BN decreased the spherulite size, increased the crystallization rate and improved the crystallization properties of P(3HB-co-4HB).