bluuebunny/crossref_metadata_2025 huggingface dataset:
The Pressure Design of Wet Shift Clutch Based on Thermoelastic Instability Analysis
Authors: Zhang Xian Quan , Li He Yan , Zheng Chang Song , Zhao Jia Xin , Ma Biao , Yang Kai Li
Published: March 2013

This paper investigated the dynamic pressure distribution on the plates within a wet shift clutch in hydrodynamic machineries for one engagement. The perturbation pressure model, heat conduction model and pressure calculation model excited by thermoealstic instability was developed. And wrote calculation programs with Maple 15 to analyze the influence of two kinds of typical friction materials, different thermal conductivity, different initial engagement speed on perturbation pressure amplitude and its impact on the pressure design margin and design radius. The results show that the margin can be decreased and design radius can be reduced, so power density increased. When the slipping speed is controlled within 16m /s, the radius can be reduced to about 1/2 of the original value.
The Research and Application of Industrial Boiler Energy Efficiency Test System
Authors: Zhang Heng Wen , Dong Shuo , Yang Fang , Shi Liang Ping
Published: March 2013

In order to improve identification of new products, we study the energy efficiency test of industrial boilers. According to related protocols and test method of the current boiler energy efficiency, we put forward an effective solution of new boiler products based on indirect procedure. We build up the model of boiler thermal efficiency test in direct and indirect procedure and analysis some key problems in indirect procedure. On this basis, we develop the Industrial Boiler Thermal Efficiency Test System, which is used in boiler industry and achieves the intended purpose.
Experimental Study on Cooling-Air Grinding of High Speed Steel
Authors: Lao Qi Cheng , Shang Zhi Yi
Published: March 2013

In the grinding of high speed steel, the high temperature grinding zone often leads to poor surface quality such as grinding burn, micro-cracks and tensile residual stresses. In the paper, the cooling-air technology was adopted to study the grinding of high speed steel. The experimental results show that cooling-air grinding can effectively restrain the grinding burns, reduce the surface roughness value and improve the surface quality in comparison with dry grinding.
Discrete Element Method for Mechanics Properties and Size Effect Analysis of Granite
Authors: Ye Yong , Kang Liang
Published: March 2013

The mechanics models formed by packed circular discrete elements and randomly distributed in a specified region were used to investigate the mechanics properties of granite, and some different sizes of discrete element models were carried out to study the size effect of mechanics properties. The simulation results suggest that there is no obvious size effect for Poisson’s ratio, compressive strength and Young’s modulus. However, the value of bending strength decreases with the increasing of the model size.
Simulation of Acoustic Field for Megasonic Bath Cleaning in Advanced Semiconductor Manufacturing
Authors: Huang Ya Ting , Dong Xiu Ping
Published: March 2013

Megasonic cleaning has been one of the most successful techniques for nanoparticle cleaning in semiconductor industry. However, the megasonic energy often causes a pattern collapse and some damage to very small structure. In this study, the distribution of sonic pressure in a wet cleaning bath with different arrangement of megasonic transducers is simulated. Megasonic wave transmits directional and will be disturbed. Thus the wafer surfaces should be arranged parallel to the sound wave direction of propagation. Convergence gain in the whole cleaning space is limited but results in great variance in local areas. Thus the wafer moving, rotating and oscillating is necessary.
Data Transmission System of Logging Cable Based on CPLD and DSP
Authors: Zhang J.T. , Hou Y.C. , Yan Z.G.
Published: March 2013

This paper has designed data transmission system of logging cable based on CPLD and DSP. This system realizes the function of modulation and demodulation in BPSK with CPLD, in which the application is flexible and the circuit is simple and reliable. The System uses DSP to realize the checking function of software CRC, improving the stability and reliability of data transmission. Practical application shows that the system works normally with stable and reliable performance and can meet the requirements of the transmission of conventional logging.
Composite-Antenna-Structure for Broadband Frequency
Authors: Kim Dong Seob , Kim Jin Yul , Hwang Woon Bong
Published: March 2013

We study a composite-antenna-structure (CAS) having high electrical and mechanical performances that we have designed and fabricated. The CAS, consisting of a glass/epoxy face sheet and a honeycomb core, acts as a basic mechanical structure, in which a spiral antenna type is embedded. To increase the intensity, a carbon fiber plate is used as a bottom sheet. This structure of the 0.5 ~ 2 GHz band has a gain of 5 ~ 9 dBi with circular polarization characteristics and reflection loss below -10 dB within the desired frequency band.
Configuration of a Thin Circular Membrane Subject to Solar Pressure
Authors: Couceiro F. , Gamboa P.V. , Silva J.M. , Guerman A.D.
Published: March 2013

This paper addresses the preliminary design of a parabolic structure suitable for specific space applications, such as in solar power collector systems, which relies upon the sole use of an initially flat circular membrane rigidly constrained across its perimeter. In particular, the possibility for this concept to make use of solar pressure as a means of obtaining the intended parabolic curvature is explored. Assuming the membrane´s film as an ideally reflecting surface, parametric studies are conducted in order to determine several parameters of interest as functions of its radius and thickness. In order to do so, a set of numerical simulations are carried out using the finite element code ABAQUS®. It is shown that the shape of the deformed membrane is very close to parabolic, therefore being capable of concentrating sunlight power over a focal plane.
Optimal Design for Front Body Structure of Space Camera
Authors: Wang Xiao Yong , Guo Chong Ling , Hu Yong Li , He Hong Yan
Published: March 2013

The primary and secondary mirrors of on-axis three mirror anastigmatic (TMA) space camera are connected and supported by its front mirror-body structure, which affects both imaging performance and stability of the camera. In this paper, the carbon fiber reinforced plastics (CFRP) thin-walled cylinder and titanium alloy connecting rod have been used for the front mirror-body opto-mechanical structure of the long-focus on-axis and TMA space camera optical system. The front mirror-body component structure has then been optimized by finite element analysis (FEA) computing. Each performance of the front mirror-body structure has been tested by mechanics and vacuum experiments in order to verify the validity of such structure engineering design.
An Engineering Model for the Impact Breakup of the Space Target
Authors: Wang Wei Jie , Shen Huai Rong , Li Yi Yong
Published: March 2013

To the question of the breakup of the space target impacted by projectile, an engineering model is developed. The space target characteristic is analyzed, and the target equivalent model is established based on the thin plate. The average size model for the impact fragment of thin plate is established depending on strain rate, fragments are discrete according to Poisson statistic and fragment distribution model is figured out. The length and velocity degraded model is set up against projectile with the shape of cylindrical rod. The simulation case is analyzed and the result indicates that the related models are effective, flexible and have important reference value.
Study on Control of the Rotational Speed of Diesel Engine under State-Switch Mode in Parallel Hybrid Hydraulic Excavator
Authors: Hu Ban Zan , Wang Qing Feng , Wang Hong Mei , Yao Hong
Published: March 2013

In parallel hybrid hydraulic excavator (PHHE) with super capacitor, the throttle position of the diesel engine is changed with the variation of the capacitor’s state of charge (SOC) of the super capacitor. When the throttle position is switched, the rotational speed of the diesel engine cannot be able to increase or decrease to the target speed rapidly enough, and it may fluctuate in large range under given conditions. Under the assumption that the loading torque of the diesel engine is invariant at the switch instant, the response of the rotational speed appears to be in different forms, which are not admitted for the normal work of PHHE. In this paper, switch types are divided into eight state-switch modes, in terms of the loading type and the amplitude of variation of the throttle position. And the paper mainly aims to the smooth transition of the rotational speed during the switched process of PHHE by the dynamic compensation of the electric motor. Experimental results show that the dynamic compensation of the electric motor can improve the dynamic behavior when PHHE is under state-switch modes.
A Design Methodology for Pile Foundation of Frame-Type Levee
Authors: Su Guo Shao , Sheng Yan Hua , Yan Liu Bin , Qian Kun
Published: March 2013

Aiming to the characteristic of mechanical behavior of pile foundation of frame-type Levee, a design methodology and its main implementation steps for pile foundation of frame-type Levee is proposed based on P-Y curve method. A practical computer program based on MATLAB and Visual Basic computer language is developed for internal force and displacement calculation of pile foundation of frame-type Levee. The methodology which had been applied in a practical engineering paves a new way for design of pile foundation of frame-type Levee.
Heat Loss Measurement and Analyses of Solar Parabolic Trough Receiver
Authors: Lu Jian Feng , Ding Jing , Yang Jian Ping , Wang Kang
Published: March 2013

The heat loss of vacuum receiver plays critical important role in solar parabolic trough system. In this paper, experimental measurements and calculation models were conducted to investigate the heat loss of solar parabolic trough receiver with receiver length of 10.2 m and diameter of 0.120 m. In general, the heat loss of receiver decreased with the receiver wall temperature, while it can approach minimum under special wind condition. The heat loss of receiver mainly included the heat loss of glass and boundary region, and the heat losses of receiver, glass region and boundary region with tube temperatures of 176.2oC were respectively 987.1 W, 762.2 W and 224.9 W. Outside the glass envelope, the convection and radiation both play an important role in the heat loss of receiver, while the heat transfer is mainly dependent upon the radiation inside the glass envelope. In addition, the heat losses of convection outside the glass and radiation inside the glass from calculation very well agreed with the experimental data.
Growth Ceiling of Energy Efficiency and Countermeasure Archetype in Electric Power Supply and Demand System
Authors: Yan Qing You , Tang Xin Fa , Cao Juan Juan , Kong Chao
Published: March 2013

Energy efficiency depends on the profit that the consumed energy contributes to human need system for the sustainable development. With the increasing importance of coordinate development of environment, economic and electric power system, it is more and more difficult to choose the right improvement path and mechanism of energy efficiency in electric-power supply and demand system. After analyzing the feedback mechanism of energy efficiency improvement of the electric power supply and demand system, energy efficiency improvement which caused the growth ceiling was found along with some inhibition factors in the process of energy efficiency improvement. In view of the energy efficiency improvement growth ceiling of the electric-power supply and demand system, the end treatment mechanism was introduced as a countermeasure which inputs environmental costs to the power supply chain. Furthermore, government guides and participates in energy efficiency investment, which was regarded as another countermeasure attached much importance. So the improvement of energy efficiency in supply and demand system of electric power can be maximized.
Energy Consumption, Conservation and Emissions Reduction Research of Beijing
Authors: Ma Li , Shen Xiao Liu , Li Zhen
Published: March 2013

Energy consumption is in support of economic development, at the same time it also results in the pollution of the environment inevitably. With the increasing of contradiction of energy supply and demand, and the serious pollution of the environment, it restricts the development of economy. In order to achieve the “Twelfth Five-Year energy planning” target, we must control the energy consumption, to implement energy-saving and emission reduction measures .Based on Chinese energy consumption status, this paper focuses on the Beijing’s energy consumption, analyzes energy consumption influences factors and the relationships among them. At the same time, this paper abstracts the model of economic and environmental on the energy consumption for the complicated relationship. Also it establishes a comprehensive multidimensional Beijing city energy consumption policy simulation and control model, pro-vides energy consumption analysis and regulation of different level and the angle respectively, covers major regulation and control means in relation to the energy consumption. On the basis of analysis of influence factors, we do the mathematical simulation and prediction between them. The results show that the prediction value is very good, the error is small. Therefore, this conclusion proves that our energy consumption control of construction model is scientific.
Research on the Formation Mechanism and Dynamic Factors of Commercial Housing Prices Based on the Correction Carey Model - Panel Data from Thirty-Five Key Cities
Authors: Lan Feng , Gu Qian
Published: March 2013

Since 2004, a nationwide commercial housing prices showing explosive growth, This paper use the Carey model studying the volatility of commodity housing price mechanism theory. By Carey theoretical correction model in 1998-2003 and 2004-2010, respectively, in two stages to establish the individual fixed effects and individual random effects panel data model focused on the monitoring of the Ministry of Construction of the 35 cities of the empirical testing of commercial housing price. Analysis concluded that the cost of land, building costs, per capita disposable income of urban residents, urban population, and psychological expectations is the main factors to promote China's real estate prices.
Comprehensive Evaluation of Power Quality Based on the Integration of Rough Set and Evidence Theory
Authors: Li Shang Yuang
Published: March 2013

In order to assess the power quality objectively and effectively, a comprehensive evaluation method of power quality based on rough set and D-S evidence theory has been proposed in this paper. The method combines rough set theory by means of defining the decision-making strength and expansion rules and using the decision-making table to obtain the basic probability assignment of D-S evidence theory, then by applying the fusion rules of evidence theory to integrate the various indicators of power quality, the pros and cons of ordering from each power quality evaluations can be obtained to achieve a comprehensive evaluation of power quality. The examples show that the results of power quality evaluation are more objective and rational by using this method. So it can prove the correctness and superiority of this method.
Ecological Civilization Construction of Eroded Red Soil Region of South China: A Case of Changting
Authors: Zeng Yue E , Wu Shi Dai
Published: March 2013

As a new research tendency, the definition of ecological civilization presents diversification in academia. Connected with the predecessors’ research results and accorded to reality of the researched area, this paper determines a definition on ecological civilization, and put forward that Ecological Civilization Construction should use a certain space as carrier, dividing the ecological civilization control area. This paper take Changting as a case, reach the idea of dividing the ecological civilization control area, integrating the philosophy and method of the major function oriented zoning. Firstly, regionalize the area of ecological civilization mainly control and protection from all the protected areas as the main body. Secondly, comprehensive evaluation of Indexes that including the aspects of economic, social, environmental, cultural and institutional about ecological civilization, are carried out at the township-level. Thirdly, we make the natural attribute of small watershed as a qualitative reference index, to identify the area of ecological civilization core development, comprehensive management, and centralized restoration. Finally, according to the division, this paper comes up with the advice of industrial layout and the measure of control.
Variation Characteristics of Artificial Grassland Carbon Storage in the Underground
Authors: Zhao Xiao Guang , Shao Chuan Ke , Song Shi Jie , Sun Di Li , Guo Li Ting
Published: March 2013

For a better understanding of the dynamics of rehabilitated grassland, carbon storage in the underground including soil and roots were studied in a space series of replaced time courses.Soil organic carbon (SOC) of the 0-100cm layer increased with the addition of restoration years.It was much more than the average of 4.46-9.95 kg m-2 in central Plateau. SOC in surface soil (layer 0-20cm) fell slightly in early stage (0-2a) and then rose rapidly. In 30a, the increase amplitude turned to be 123% and it reached the maxmum.SOC in this layer was significantly correlated with an average value for the whole 0-100 cm profile.So SOC storage, in the 0-100cm layer, can be well estimated using values for the 0-20 cm layer. Alfalfa underground biomass carbon storage rose first and then reduced. It reached the maxmum in 10a. The carbon storage of weed roots increased continuously and was still less than that of alfalfa roots in 30a.
An Exploration of Provincial Low-Carbon Economy Evaluation System Based on Principal Component-Variable Fuzzy Evaluation
Authors: Hu Ji Min , Gu Jian Long , Hu Chang Cui , Wang Hai Feng
Published: March 2013

According to indicators’ information repetition and subjectivity of the indicators’ weight set during the variable fuzzy comprehensive evaluation, Principal Component analysis can help solve the weight of the relative indicators and reduce comprehensive evaluation dimensions of the variable fussy comprehensive evaluation. This paper has made a comprehensive evaluation of the status quo of Yunnan’s low carbon economy development(2005-2009), which turns out to be more practical compared with the mere variable fussy theory analysis, thus, principal component-variable fuzzy evaluation is a kind of feasible way to analyze the regional low carbon development status.
Suppressing Knock of the Dual-Fuel Engine by Injection Timing under Pressure Boundary Conditions
Authors: Zhang Cheng Wei , Xiao Bing
Published: March 2013

The engine knock has direct relation with the energy release rate. The faster combustion speed is, the higher heat release rate is. If heat release rate is too high, it will deteriorate reliability of the engine. A dual-fuel engine combustion mechanism model is established and intake pressure boundary conditions influence on the dual-fuel engine reliability is studied. Injection timing can supress engine knock and inprove engine reliability. Studies have shown that the greater the intake pressure, the smaller injection timing should be selected and the smaller the intake pressure, the larger injection timing should be selected. Appropriate injection timing can ensure reliability and power of the engine.
Effects of Non-Uniform Circumferential Heating and Inclination on Critical Heat Flux in Smooth Round Tubes
Authors: Hu Zhi Hong , Chen Ting Kuan
Published: March 2013

Experimental investigation of the critical heat flux (CHF) in smooth round tubes with circumferentially variable heating was carried out. The riser tubes with 0, 20, 90-degree inclinations from the horizontal were electrically heated. The measurements were carried out for pressure between 13 and 21MPa, mass flux between 600 and 900kg/m2s. The peak-to average heat flux ratio was amounted to 1.6. CHF data of uniform heating were also tested. The test results show that the initial CHF is always observed at location of peak heat flux in vertical tubes with non-uniform heating. In horizontal and inclined tubes with side-heating the transit from a top to side initial indication of CHF occurs by increasing the mass flux and the pressure to certain values. The Initial CHF of non-uniformly heated tubes is fairly agreement with the values of uniformly heated tubes.
Technical and Economic Analysis of 150MW Turbine Unit about Two Reconstruction Modes for High Back Pressure Heating
Authors: Duan Jun Zhai , Zheng Wei , Wang Xue Dong , Hao Yu Zhen
Published: March 2013

In this paper, the characteristics of two modes of high back pressure reconstruction techniques for 150 MW reheat turbine units were researched. One was reconstruction of double back pressure and double rotors and the other was one-off reconstruction of LP cylinder. The former redesigned for lower pressure(LP) rotors for running at high back pressure, and hydraulic coupling bolts adopted to achieve the switch of low pressure rotors that run at high and lower back pressures. The one-off reconstruction of LP cylinder has achieved the switch of static and dynamic blades between high and low pressure. The two reconstruction both realized heat supply on the high back pressure condition, utilized cold source loss and increased the unit efficiency. After reconstruction, the economic index under both normal back pressure condition and high back pressure heating condition have been obtained by performance test. Under the high back pressure heating condition, the unit heat rate reaches 3700-3800kJ/kW.h, and the thermal efficiency has achieved 95-97%.
Study of Economic Specific Frictional Resistance in Hot Water Heat Supply Net Work in Xi’an
Authors: Zhao Jian Hui , Huang Xi
Published: March 2013

Based on technical and economic analysis,apply optimal theory to explore the optimal values of economic specific frictional resistance and put form and a sound theory formula .Apply the formula to the real project and calculate the values of the economic is specific frictional resistance optional pipe diameter and velocity on different heating-supply scale under current prices.
The Systems Emulation Study of the Dynamic Heat Load for Underground Structure Envelope
Authors: Wang Li Jun , Miao Xiao Ping , Wang Rui Hai , Li Wei Hua , Yang Jun , Li Yong , Jiang Feng , Zhou Xiao Feng
Published: March 2013

Whether the results of the dynamic heat flux from the underground engineering envelope are accurate, may influence the accuracy of calculating the transient heat load and could affect the initial cost and actual operation of the air-conditioning system in the underground engineering. The paper is to find out the mechanisms of the heat transfer in the underground engineering envelope. The mechanisms of heat transfer in normal underground engineering envelope, simplified calculation for heat transfer in the underground engineering envelope and the dynamic emulation of the heat load of the underground engineering envelope.
A Study on Reducing the NOx Emission of the L21/31 Medium-Speed Marine Diesel Engine for IMO Tier Emission Legislation
Authors: Xiao Min , Chen Hui
Published: March 2013

The KIVA-3V program was used to make numerical simulation for L21/31 type of medium-speed marine diesel engine about the NOx emissions and the affection of NOx changing process on different variable parameters under the Tier Ⅱstandard. On this basis, a discussion towards the NOx emission of the model fueling with dimethyl ether (DME) to meet the Tier Ⅲ standard is offered. The results show that reducing the intake temperature, load and speed, postponing the fuel injection timing and intake lag angle properly can decrease the NOx emissions within the limits of NOx in TierⅡ standard. Comparing the results of the numerical simulation of DME and diesel fuel, the NOx emission of the former one is 60.85% of the latter one, and the NOx emission of changing variable parameters on DME engine is 35.56% of the original type of diesel engine, very close to the Tier Ⅲ.
The Prospective Analysis of Marine Dual Fuel Engine Application Based on Emission and Energy Efficiency
Authors: Yang Bing Song , Sun Pei Ting , Huang Lian Zhong , Song Dan
Published: March 2013

The new regulations on emissions and energy efficiency in the amendment to MARPOL Annex VI will become effective on January 1, 2013. The old-type marine main engine is difficult to come up to the new standard. Determining how to reduce the NOx, CO2 emissions and improve energy efficiency of ships draws a lot attention. The adaptability of marine dual fuel engine on the new regulations, EEDI and EEOI was studied, and the prospect of dual fuel engine is analyzed in this paper. To some extent, it has guiding meaning in the development of the marine main engine.
Review of Smart Grid Development in China
Authors: Yu Juan , Yin Tao , He Ming , Wang Cheng Jin
Published: March 2013

Smart grid is recognized as the development direction of future grid. The text described the current development of smart grid in China from four aspects of the basic features of smart grid, and analysis some technology researches in smart grid, and also put out the current technological bottleneck exists. Meanwhile direct for China's future development of smart grid.
Evaluating Effects of Expanding Grain-Based Fuel Ethanol and Cassava-Based Fuel Ethanol on Agriculture in China - A Multiplier Decomposition within a Social Accounting Matrix Framework
Authors: Zhao Lian Rong , Ge Jian Ping
Published: March 2013

In this paper, multiplier decomposition is adopted to examine the effects of expanding grain-based fuel ethanol and cassava-based fuel ethanol on agriculture in China. The results show that, reasonable development of grain-based fuel ethanol has a greater role than cassava-based fuel ethanol in accelerating China’s economy, improve rural household’s income, and mitigate gap between rich and poor
Improve the Frequency Quality of Power System Using Decentralized Intelligent Loads
Authors: Cheng Li , Han Dong Xu , Li Zhong Wei , Zheng Dong
Published: March 2013

Frequency is an indicator of the balance between electricity generation and consumption. Maintaining the frequency stability is the first of all for a stable operation of power system. After analyzing the traditional power system’s primary frequency control, secondary frequency control and tertiary frequency control, the electric heater, water heater, refrigerator, air conditioner and other domestic electric appliances are tried to use to improve the frequency quality as the decentralized intelligent loads based on the thought of “demand following supply”. The statistics of the overall power of different domestic electric appliances of several countries are given. It indicates that the domestic electric appliances can be used to improve the frequency quality from the overall power. The operating characteristics and control requirements of different domestic electric appliances are analyzed. Their control strategies are put forward and model of decentralized intelligent loads is constructed. A series of questions of technology, economic and policy that need to be solved while utilizing the decentralized intelligent loads to control the power system frequency are put forward.
Pattern Recognition Based on Integrative Vulnerability Mode for Elcctric Power Grid
Authors: Zhang Meng , Zheng Liang HUA , Lin Tao , Wang Hua Long , Fang Fei
Published: March 2013

In recent years, with the happening of large-scale power cut accidents, the electric network has been concerned widely increasingly. Pattern recognition which could be used in online analysis, can get rid of the mode limit of the operation characteristic of description system, and its counting volume is less influenced by system scale, also its general assessment is in a fast speed. In this text, it elaborates the conception of the power grid vulnerability and some kinds of available ways of assessing vulnerability, and it also tells us the target of electric network’s integrative vulnerability based on integrative vulnerability mode for electric power grid, and used in pattern recognition, which its the sensibility and necessity of pattern recognition has been verified by the IEEE-39 system.
Short-Term Wind Speed Forecasting Based on Time Series-State Transition Method
Authors: Ji Jie , Shen Yong Tao , Tan Meng Si , Wu Li Ning , Zhang Jian Hua , Liu Zong Qi
Published: March 2013

Wind speed forecasting is of great significance to the improvement of grid stability and the reduction of operating cost. Because of the high volatility of wind speed, the accuracy of current forecasting methods have yet to be improved. This paper established a time series-state transition model to solve this problem, which uses state transition to revise the results of time series forecasting. The improvement in accuracy is proved by the analysis of a practical example.
Research of Cable PD Detected Technology Based on Variable Frequency Oscillation Wave
Authors: Zhang Zong Xi
Published: March 2013

With the accelerating construction of strong smart grid, and the grid voltage level rising, performance requirements for the electrical insulation of electrical equipment also continue to increase. The ( XLPE ) cable with good electrical and thermal performance and simple structure, the manufacturing cycle is short, safe and reliable power supply etc, which is widely used in power system ; Partial discharge is in the power cable to run a larger security risks is a sign of deterioration of the cable insulation is caused by insulation deterioration of important reasons . In this paper, based on variable frequency resonant damped oscillatory wave voltage XLPE cables and their connectors partial discharge site detection technology, the damped oscillatory wave voltage and power frequency voltage equivalent; the field test requirements, parameter optimization and performance detection impedance, and use advanced digital signal processing methods to analyze the test data processing, to provide a reference for the cables and their joints more accurately determine the insulation condition.
A Weather Dependent Failure Rate Model for Overhead Lines
Authors: Jin Jun , Liu Wen Xia , Liu Zong Qi
Published: March 2013

In power system planning and operation, accurate assessment of overhead lines outage rate is essential for making timely decisions. The overhead lines are often influenced by many random events, such as accidents and weather conditions, resulting in power outages. Especially, the reliability of the overhead lines is subjected to weather conditions to a great extent[9]. At present, research about weather conditions dependent reliability is abundant, but many of them are based on synthetical weather, little of them base on specific weather conditions such as typhoon and thunder .This paper proposed outage model of overhead lines dependent upon typhoon an thunder. In power system planning and operation, accurate assessment of failure rate is essential for making informed decisions, The outage model proposed in this paper has significant meaning for the research of risk assessment of power systems.
A Minimum-Energy Consumption Control Algorithm for Omni-Directional Mobile Robots
Authors: Wang Jian Bin , Yang Yi Min , Li Jing
Published: March 2013

A minimum-energy consumption control algorithm is applied to motion control of a four-wheel drive omni-directional mobile robot (FDOMR) in actual application environment. After establishing the robot’s dynamic equations with motor model, we have chosen a practical cost function as the total energy drawn from the batteries. Considering the translation and rotation, we have found out the velocity curve by optimal control theory. Various simulations are performed and the consumed energy is compared to the normal control method that without minimum energy consumption control. Simulation results reveal that the energy saving is much more compared to the traditional control, the operational time of the FDOMR with given batteries is lengthened and the efficiency of battery is improved.
The Applied Research of the Hilbert-Huang Transform and Wavelet Transform in the Fault Location of Transmission Line
Authors: Li Zhi Bin , Wu Bao Xing , Xu Yun Hui
Published: March 2013

In the process of the Hilbert-Huang transform, empirical mode decomposition (EMD) may result in the end effect and modal aliasing when processing data, so proposing Ensemble Empirical Mode Decomposition (EEMD) instead of EMD, and assessing the accuracy of the two decomposition processes according to the total energy of the signal before and after the decomposition. Take a comparison between the Hilbert-Huang transform and the wavelet transform, the localization showed that the Hilbert-Huang transform is better than wavelet transform in the fault location of transmission line.
Conversion of Glucose to Levulinic Acid Catalyzed by ZSM-5 Loading SO42-/ ZrO2
Authors: Liu Ying , Lin Lu , Sui Xiao Yu , Zhuang Jun Ping , Pang Chun Sheng
Published: March 2013

Hydrolysis of glucose to produce levulinic acid catalyzed by ZSM-5 loading SO42-/ ZrO2 was studied in this paper. The effects of different factors such as catalyst amount, reaction temperature, reaction time on the yields of levulinic acid and hydroxymethyl furfural were investigated. It was found that the highest yield of levulinic acid was 55.03% (molar percent) under the conditions of catalyst amount 3 g, reaction temperature 180 °C and reaction time 2.5 h. Surface structure of catalyst was analyzed by FT-IR, indicating that crystallinity of catalyst was 0.66.
Breaks Strip Breakdown with the Parameter Identification Law Diagnosis Mouse Cage Asynchronous Motor Rotor
Authors: Wu Qiao Shan
Published: March 2013

According to the three-phase squirrel-cage asynchronous motor rotor broken bar fault, presented with parameters identification method of asynchronous motor parameter identification to monitoring and diagnosis of rotor resistance variation of rotor bar breaking principle. Choose a three-phase squirrel-cage asynchronous motor in three working points of experiments, results show that the method is correct and feasible. This method is based on the three-phase squirrel-cage asynchronous motor steady state model parameter equation, using the method of least squares identification parameters, and consider the effects of temperature on the parameters, by the parameter variation in diagnosis of broken rotor bar fault. Advantages of simple scientific method, this method can also be used in conjunction with other methods and, on the three-phase squirrel-cage asynchronous motor rotor has no fault diagnosis.
Design of Fault Diagnosis Expert System of Transformer
Authors: Sun Tao , Liu Hai Bo
Published: March 2013

The transformer fault diagnosis expert system design knowledge representation and reasoning mechanisms are the key issue. Characteristics of transformer fault diagnosis system based on human experts, learning on the basis of the human expert diagnosis of transformer faults, to build a transformer fault diagnosis expert system of systems architecture, knowledge representation and reasoning mechanisms for a more detailed analysis and discussion.
Microstructure and Corrosion Behavior of AZ91-0.4%Nd Magnesium Alloy
Authors: Zhang Jumei , Wang Zhi Hu , Sun Wan Chang , Zhu Ming
Published: March 2013

The corrosion behavior of AZ91-0.4%Nd alloys was investigated by immersion test in 3.5wt.% NaCl at 25°C. The phase compositions and microstructure of the AZ91-0.4%Nd alloy were characterized by XRD and OM, respectively. The results show that the number of Nd element in the AZ91 magnesium alloy has effect on the grain refining efficiency, and the granular or acicular Al3Nd phase precipitate in matrix.The corrosion products of the AZ91-0.4%Nd alloy mainly composed of Mg(OH)2 and Al. The addition of Nd element significantly refine the microstructure and improve the compactness of corrosion products of AZ91-0.4%%Nd magnesium alloy, as a result the corrosion resistance of alloy was improved obviously.
Load Effect on 1Cr18Ni9 Stainless Steel Wires’ Fretting Behaviors in Metal Rubber Dampers
Authors: Dong Xiu Ping , Huang Ming Ji
Published: March 2013

Cool-drawn 1Cr18Ni9 stainless steel wires of  0.1~0.5 mm can be woven and punched to prepare metal rubber (MR) dampers. There is certain amount of contact point/surface on wires in the transformable component and the displacements between wires are at micron levels. This kind of dampers usually works at variable load. In order to study load effect on wires’ fretting behaviors i.e. MR components’ vibration fatigue behaviors, the two  0.3 mm wires are fixed in 0.1 mm-deep grooves cutting on the traditional column-block samples and dry fretting experiments at load of 20N, 25N and 30N are made on SRV high temperature wear tester. Experiments showed that wear course of ‘fretting cell’ could be plotted as four phases: polish, adherence, forming of the third bed and stabilization. Based on data of MR vibration fatigue experiment and reference report, parameters of fretting experiment are designed and friction coefficients are collected at load of 20N, 25N and 30N. Results indicate that friction coefficient rises at the beginning of fretting and it will reach the stable phase at point of 350, 240 and 120 fretting cycles respectively. In wire’s stabilization wear phase the value of friction coefficient fluctuate around 0.4-0.42 and the amplitude is below 0.1. Friction coefficient curves at the three degree of load are close to each other. Fretting traces are measured and studied by OLYMPUS LEXT OLS3000, laser scanning confocal microscope (LSCM), and KEYENCE VHX-600, three-dimensional microscopy. This paper compares the load effect on wires’ fretting behaviors and supply data support for MR materials’ application as dampers.
Experimental Research on Combustion Characteristics of Palm Kernel Meal in a Circulating Fluidized Bed
Authors: Fan Xiao Xu , Yang Li Guo , Ma Yu Qin , Chen Tian Ju
Published: March 2013

In this paper, the combustion characteristics of palm kernel meal were investigated in a circulating fluidized bed (CFB 100)(height=3000mm, inner diameter=100mm). The results showed that the temperature and pressure of the furnace were relatively steady. The contents of SiO2, Na2O and K2O of the bed material ranged smoothly with the process, the particle size of the bed material fluctuated slightly. The alkali metal contents of bed material were ranged from 1.5% to 3.5%.
A Fuzzy Buffer Setting Method for Project Scheduling under Uncertainty
Authors: Zhou Yi Kun
Published: March 2013

The buffer setting methods are useful ways to deal with the uncertainty. However, few has concern how to estimate the safe time of each project activity, which is used to set the buffer, when historic information of project is not enough. In this paper a fuzzy buffer setting method is proposed to solve the shortage. The fuzzy method has three steps: estimate the fuzzy duration, calculate the safe time and determine the buffer size. A calculation example is also given to introduce the detail procedure of this method.
A Study of Transport-Oriented Development (TOD) Based on the Frequency Scale-Fuzzy Comprehensive Evaluation Method
Authors: Han Fei , Xiao Gui Ping
Published: March 2013

Transport-Oriented Development (TOD) is an effective solution to urban traffic congestion, environmental pollution, noise pollution, and reduce energy consumption. And it is the best mode to solve urban development problems currently. This paper uses frequency scale-fuzzy comprehensive evaluation method to explore the inadequacies of modern urban development. And use Matlab to visualize this approach. Lastly put forward feasible suggestions for the city's TOD development in order to guide the cities’ sustainable development.
Application of a New Improved Ant-Algorithm in TSP
Authors: Li Chen Bing , Jia Hua Fei , Chen Wei Dong , Jia Yu Wen
Published: March 2013

Firstly, this paper introduces the ant colony algorithm and its principle, model and the process to realize, meanwhile, it analyses the reasons for the premature stagnation phenomenon of ant colony algorithm. Secondly, refresh and local optimal search strategy on the optimal, worst pheromone will be introduced here based on the original algorithm, as well as two line equations to avoid crossing paths, in order to expand the scope of the feasible solutions, avoid premature stagnation, and accelerate the speed of convergence. Finally, with eil51 of TSP to be an example of simulation calculation, the result shows the superiority of the improved ant colony algorithm.
Error Analysis of Approximate Ripple Borrow Subtractors
Authors: Yuan Wei Jun , He An Ping , Wu Jin Zhao
Published: March 2013

In this article, we study the output error in terms of the delay of the arithmetic subtractor circuit. By the formal analysis the borrow in arithmetic subtractor, especially the borrow chain, we model the discrete signals in the continuously, then construct the output error model and energy consumption model of the ripple borrow subtractor circuit. With these models, we do the trustable analysis formally.
Research and Design of Mixed Fieldbus System
Authors: Ren Kai Chun , Zhang Qian , Liu Xiao Jun , Li Shi Gang , Wang Qiu Hong
Published: March 2013

Complex control system bears a heavy task, different field equipment have different requirements in reaction time, transmission speed, real time of fieldbus. Considering the characteristics of industrial Ethernet and fieldbus, mixed fieldbus was combined with Ethernet network; CAN - Ethernet gateway of CAN fieldbus was designed as example which can achieve the interconnection between upper and lower of the control system; the enterprise information network and control network got unified. Further, the system could integrate with internet to make it more practical.
A New Grey Bass Equation for Modelling New Product Diffusion
Authors: Wang Zheng Xin
Published: March 2013

A novel grey Bass model with a power exponent (Grey Bass Power Model) was proposed, and the related parameter-packets of the model were deduced. A nonlinear programming method was employed to optimize the grey parameters and improve the accuracy of the grey Bass model. The results show that GM(1,1) model, GPM (1,1) model, grey Verhulst model and grey Bass model are the special examples of grey Bass power model. The actual example of product diffusion shows the modelling accuracy has been remarkably improved by using the new model.
The Effect of Substrate Temperatures on CdS Film Prepared by Thermal Evaporation
Authors: Shao Qiu Ping , Zhang Hua , Men Chuan Ling , Tian Ziao , An Zheng Hua
Published: March 2013

A suitable deposition method of CdS is necessary for the high performance CIGS(Cu(In0.7Ga0.3)Se2.2) solar cells. In this paper, CdS films were deposited onto glass substrates at the substrate temperture of 50°C、100°C、150°C by thermal evaporation, the effect of the temperature were presented. CdS film deposited at substrate temperture of 150°C was annealed at 150°C for 30min. All films were characterized for their morphology, structure and optical property using scanning electron microscope(SEM), X-ray diffractometer(XRD) and UV–VIS–IR transmittance respectively.The quantum efficiency of the fabricated solar cells with annealed CdS buffer layer was also enhanced at short wavelength. This new method leads to the improved performance of CIGS solar cells and also simplify the whole fabrication technology.
The Research of Finite Element Modeling and Contacts for Connecting Bolts of Wind Turbine
Authors: Li Guo Feng , Meng Chun Ling , Ma Chen Chao , Wu Nian Peng
Published: March 2013

Combined with characteristics of wind turbine bolt connection structure, with the connection of pitch bearing inner ring and the blade root as the research object, through the finite element analysis software Ansys, establish various connection model, using the multiple point coupling constraint and nonlinear contact for finite element analysis , research on bolt truss element types, connections of each component and the establishment of contact, then obtain and analysis affects of finite element calculation with different element types of bolt truss ,contact relationship ,compared with theoretical results, put forward feasible finite element analysis scheme of wind turbine bolt connection, and provide basis for the structure design and intensity analysis.
Large-Eddy Simulation of Flow around a Horizontal-Axis Wind Turbine
Authors: Luo Kun , Zhang San Xia , Gao Zhi Ying , Wang Jian Wen , Zhu Sheng Hua , Zhang Li Ru , Fan Jian Ren
Published: March 2013

Three-dimensional ﬂow around a horizontal-axis wind turbine has been investigated with LES method coupled with sliding mesh and experimental measurement. The boundary conditions are set as the same as those of the experiment. The images of the pressure distribution, flow rate distribution, turbulent intensity, velocity vector and vortices of the wind turbine are presented to show the three-dimensional flow characteristics around the wind turbine. The relationship between flow and sound is further studied by analyzing the flow parameters pulsation spectrum to get the sound pressure level. LES results are compared with the wind-tunnel measurements collected with PIV, and good agreement is observed. The results serve as a reference for optimum design of the wind turbine with high functional performance and low level noise generation.
Numerical Simulations of Spherical Vertical-Axis Wind Rotor
Authors: Huang Yong Yu , Mo Qiu Yun , Zhang Xu , Zhou Zu Peng
Published: March 2013

In this paper, the effects of the shape of three types of the blade on power coefficient of Savonius rotors are studied by simulating the model using numerical simulation under the same conditions. For this purpose, three spherical rotors with different configurations but identical number of stages and blades, aspect ratio and overlap keeping the identical projected area of each rotor are constructed. The geometries of blade of the three rotors are a plane, a semi-circle and a quarter of sphere. The building data are calculated on the basis of the nominal wind velocity V= 10m/s and the speed ratio λ= 0.3 with an industrial flow simulation code (ANSYS-Fluent). The result shows that the rotor with semicircular blades has a higher value of power coefficient in comparison with other rotors.
Reliability Modeling of Wind Farm Considering the Outages of Connection Cables
Authors: Qiu Guo Bing , Liu Wen Xia , Zhang Jian Hua
Published: March 2013

Considering the randomness of wind speed and wind direction, the partial wake effect between wind turbines (WTs) in complex terrain was analyzed and a multiple wake model in complex terrain was established. Taking the power output characteristic of WT into consideration, a wind farm reliability model which considered the outages of connection cables was presented. The model is implemented in MATLAB using sequential Monte Carlo simulation and the results show that this model corrects the power output of wind farm, while improving the accuracy of wind farm reliability model.