bluuebunny/crossref_metadata_2025 huggingface dataset:
Uncertainties with Respect to Active Vibration Control
Authors: Pelz Peter F. , Bedarff Thomas , Mathias Johannes
Published: September 2011

The content of this work is the presentation of the prototype of a new active suspension system with an active air spring. As being part of the Collaborative Research Unit SFB805 “Control of Uncertainties in Load-Carrying Structures in Mechanical Engineering”, founded by the Deutsche Forschungsgemeinschaft DFG, the presented active air suspension strut is the first result of the attempt to implement the following requirements to an active suspension system: Harshness and wear: Reduced coulomb friction, i.e. no dynamic seal. Plug and drive solution: Connected to the electrical power infrastructure of the vehicle. Vehicle and customer application by software and not by hardware adaption. These requirements were defined at the very beginning of the project to address uncertainties in the life cycle of the product and the market needs. The basic concept of the active air spring is the dynamic alteration of the so-called effective area. This effective area is the load carrying area A of a roller bellow and defined by A:=F/(p-pa). F denotes the resulting force of the strut, p the absolute gas pressure and pa the ambient pressure. The alteration of this effective area is realized by a mechanical power transmission, from a rotational movement to four radial translated piston segments. Due to the radial movement of the piston segments, the effective area A increases and so does finally the axial compression force F. The prototype presented in this paper serves as a demonstrator to proof the concept of the shiftable piston segments. This prototype is designed to gather information about the static and dynamic behavior of the roller bellows. Measurements show the feasibility of the concept and the interrelationship between the piston diameter and the resulting spring force.
Control of Uncertainties in Metal Forming by Applications of Higher Flexibility Dimensions
Authors: Groche Peter , Kraft M. , Schmitt S. , Calmano S. , Lorenz U. , Ederer T.
Published: September 2011

It is widely accepted that fluctuations in market demands and product life cycles are often unpredictable. Based on these uncertainties, companies cannot calculate with constant demands. Manufacturers are also confronted with quality fluctuations in semi-finished parts that lead to various product qualities. This paper identifies the most relevant uncertainties for companies and gives answers how manufacturers can deal with these problems. It also shows recent developments in the field of flexible forming using servo press technology. Hereby the focus is set on 3D Servo Presses, providing various options for accomplishing uncertainties.
Practical Calculation Method for Crack Torque and Ultimate Torque of Special-Shaped Columns under Actions of Pressure and Torque
Authors: Jiang Ming , Xu Yu Ye , Qiu Zheng He , Luo Yi
Published: September 2011

The experimental results of crack torque and ultimate torque of six reinforced concrete special-shaped columns under the combined actions of pressure and torque were presented firstly. Then, the calculation formula suggested by the Chinese Code for Design of Concrete Structures for the crack torque and ultimate torque of rectangular columns under the actions of pressure and torque were used for reference to determine the expression forms of crack torque and ultimate torque of special-shaped columns. Moreover, the special-shaped cross section was dealt as a combination of two rectangle cross section. A practical calculation method for crack torque and ultimate torque was proposed by data regression of experimental results.
The Critical Construction Techniques of Preventing Quality Defects of External Wall Insulation
Authors: Ouyang Chen Bing , Chen Ying
Published: September 2011

Since China's enforcement of building energy saving standards, external insulation technology has been applied in a mount of buildings. However, four common defects of it, namely crack, shedding and hollow, leakage, frost and condensation, had gradually appeared. This study tries to find out the critical construction techniques of preventing these defects which are closely related to quality in order that engineers pay more attention to them during construction. Literature research and field investigation to engineers and technicians are adopted. Designed questionnaires, including 61 kinds of detailed defects causes and relevant preventive measures, are used in the survey. Through statistical analysis of survey data, the mesh, plastering mortar configuration, etc. 10 detailed causes are suggested as main defect reasons according to harm grade. Meanwhile, corresponding 15 highly effective construction technical countermeasures are put forward finally.
Calculation of Flexural Capacity of Steel Reinforced Concrete Beams Strengthened with Near-Surface Mounted CFRP Rods
Authors: Chen Wei Hua , Wu Mei Qin
Published: September 2011

Based on earlier theoretical works on RC beams ,the mechanical properties of steel reinforced concrete beams strengthened with NSM (near-surface mounted) CFRP (Carbon fiber reinforce polymer) rods are further investigated theoretically including theirs failure mechanism and load ability. According to the stress patterns of steel reinforced concrete beams strengthened with NSM CFRP rods and different position between neutral axis and steel, the discriminant formula of the boundary destroys and the formula of cross-section flexural capacity calculation are put forward by using limit equilibrium theory.The formula is expressed clearly, simple and easy to use.The depth of compressive region is given in view of different failure types.
Experimental Behavior of One-Way Concrete Slabs at Large Displacements
Authors: Zhang Da Shan , Dong Yu Li
Published: September 2011

This paper presents the tensile membrane action on one-way reinforced concrete slabs, and two full-scale specimens with one edge clamped and one edge simply supported were tested at large displacements. The details of the two tests including support conditions, arrangement of reinforcements and layout of displacement transducers are described. The test results show that the load-carrying capacity of the two slabs is significantly improved due to the tensile membrane action, about 26.6% more than the predicted value using the well-established yield-line theory. Until maximum vertical displacement reached 1/15 of the span-length, the slab did not fail and carried the load steadily.
Analysis of Cracks on the Containment of Loop Nuclear Power Stations for 60 Days
Authors: Sun Yu Zhuo , Yi An Hai , Lin Jie , Qiao Peng
Published: September 2011

The relation of tensile strength ＆ temperature stress and concrete fissure was researched firstly , then it showed the causes of late cracks on concrete by theoretical calculation, the result provided a simple theoretical calculation method to avoid concrete fissure. The construction methods to control the fissure was proposed: early strengthening cooling, managing maximum temperature of concrete through lately heat preservation, and overtime to preserving concrete moisture for controlling the late strain on mass concrete. This research has a great significance for controlling the fissure.
Study on Critical Corrosive Ratio of Reinforced Concrete Based on Monte-Carlo Method
Authors: Chen Yue Shun , Liu Li
Published: September 2011

Based on the relationship between the displacement and the corresponding strain in protective layer concrete during their corrosive expanding, the strain in protective layer arrives the critical strain have been think as the cracking condition, then a certainty critical corrosive ratio model has been constructed in this paper. Considering the probability distribution and the statistical characteristics of concrete protective layer thickness c, reinforced bar diameter dst and the effectively volume expansion coefficient neff, the Monte-Carlo method have been used to simulate the critical corrosive ratio ρcr, its probability distribution has been shown in good agreement with Weibull distribution and lognormal distribution in results. Through the constant current polarization accelerated corrosion test, the critical corrosive model has been validated. With comparison of critical corrosive ratio which be obtained with the test and the model simulation results respectively, where a good agreement have been shown.
Logic Analysis of Event-Based Emergency Handling
Authors: Yuan Jin Jun , Huang Quan Yi , Yuan Hong Yong
Published: September 2011

Event-based emergency handling is a high-efficiency decision process of the choice of emergency information resources, the acquisition of emergency knowledge, and the optimizing arrangement of emergency information resources through the logical relationships between emergencies and related emergency information resources. With the development of emergency rescue theory and computer science and technology, the realization of emergency management informatization and intellectualization is of far reaching importance, on the basis of the establishment of event-oriented handling logical relationships, the construction of emergency management platform, the unified management of emergency information resources and the on-line emergency handling. Centered on emergencies, this paper discusses the respective corresponding relationships of emergency and emergency information resources, emergency knowledge, emergency response plans, paradigm cases, relative laws and a series of decision actions on emergency handling, risk assessment and risk analysis etc. It also illustrates the functions and meanings of the correspondence configuration.
Reliability Analysis for Differential Expansion of Steam Turbine by Saddlepoint Approximation
Authors: Li Le Xin , Su Chang Qing , Jin Ya Juan
Published: September 2011

The reliability analysis for differential expansion of steam turbine is discussed extensively. The ultimate state equation of differential expansion of steam turbine is proposed according to stress-strength interference theory. Based on the premise that the probability distribution of random parameters has been known, the differential expansion of steam turbine is analyzed by saddlepoint approximation method. The probability density function and cumulative distribution function of the ultimate state equation are accurately and quickly obtained by the way of saddlepoint approximation and, as a result, the saddlepoint approximation method is proved accurate with high computing speed in comparison with the Monte-Carlo method. Therefore, the application of the saddlepoint approximation method is accurate and efficient.
Agent Construction System Application and Improvement Discussion in the South-to-North Water Diversion Project
Authors: Guo Yong Cheng , Li Jin Feng , Li Jian Lin
Published: September 2011

This paper describes the agent construction system of development and the associated building regulations in China. A brief overview of the South-to-North Water Diversion Project and the practical application of agent construction system in the Beijing-Shijiazhuang section of the South-to-North Water Diversion Middle Route Project (SNWDMRP) is made and specific recommendations to carry out the system to the next diversion project construction is put forward. Existent problems and corresponding measures applied to the agent construction system are discussed, such as the situation and choice of agent construction corporation, agent construction project selection, responsibilities and rights of the agent construction corporation, incentive and punishment mechanism, construction supervision and management and so on. Useful exploration on the application of agent construction system is made in hydraulic and hydroelectricity engineering field.
Mitigation of Wind-Rain-Induced Cable Vibration in Cable-Stayed Bridges: Energy Cost Assessment
Authors: Wang Ling Yun , Wang Quan Feng
Published: September 2011

The cables in a cable-stayed bridge usually possess low inherent damping and are prone to vibrate by many factors. The wind-rain-induced vibration of the prototype stay cable is a special vibration problem associating with rain and wind. Many methods have been proposed to mitigate wind-rain-induced cable vibrations such as mechanical measures, aerodynamic modification, and control technology. Active control technique has significant control capability because of utilizing the external energy supply but it may not be realistic to large civil engineering structure due to enormous power demand. The two-stage control method has been proposed to control the wind-rain-induced cable vibrations of the prototype stay cable. The studies are carried out to investigate the energy cost features of the control forces as a design guideline.
Transfer Mechanism and Experimental Study of Tower of Liede Bridge
Authors: Wang Wei Feng , Chen Xi Long , Shi Sai Ying , Zheng Heng Bin
Published: September 2011

The text, drawing Liede Bridge as project background, gives a detailed analysis about the transfer mechanism of the cable tower, with the aid of analytic theory methods, FEM calculations and model tests. While these model tests and calculations show that, on one aspect, the cable tower meets design requirements and falls into a safe state under construction load and bridge load. On another, its theoretical values are in accordance with the test values generally. To illustrate that the cable tower's transmission is in line with the plane-stress problem in Elasticity Theory verifies the overall static performance in cable tower along with the theory of design calculation.
Experimental Investigation on HRBF500 RC Circular Pile under Low Cyclic Reversed Loading
Authors: Fu Qian , Liang Shu Ting , Zhu Xiao Jun
Published: September 2011

Six concrete piles reinforced with 500MPa fine-grain steel bars were tested under low cycle reversed loading to study the seismic behavior such as failure patterns, characteristics of hysteretic and skeleton curve. Three parameters, longitudinal reinforcement strength, reinforcement ratio and axial compression ratio were taken into consideration. The main failure patterns as well as hysteretic curve of those piles were obtained, and influence of each of the three parameters on the ductile behavior, ability of energy dissipation and law of strength degeneration were analyzed. The experimental results indicate that the mechanical behavior of reinforced concrete low cyclic reversed loading columns with fine grain high strength reinforcement is similar to normal reinforced columns. The concrete piles reinforced with 500MPa fine-grain steel bars show good seismic performance and 500MPa fine-grain steel bars can be used in seismic design.
Research on Ground Settlement due to EPB Shield
Authors: Yan Zhi Gang
Published: September 2011

The surface settlement is affected by many factors due to EPB shield. This paper takes the shield construction of Guangzhou Metro Line 5 as an example, carries out three dimensional numerical experiments on the ground settlement rule. The result indicates that soil warehouse pressure and the efficiency of grouting is important factors of the surface displacement. To increase grouting pressure and shorten the grouting time can reduced the ground settlement in effective. With the increase the soil warehouse pressure, the settlement behind the working face is reduced and the front working face is increased. When the soil warehouse pressure is at the over balance condition, the raising ground is increased and the settlement is reduced. The value of settlement is much larger than the value of raising. So to increase the soil warehouse pressure is another effective method to reduced the ground settlement on the premise that the front soil body of shield does not be destroy.
Application of Semi-analytical Method in Transient Thermal Field of Pavement Structures
Authors: Mei Fu Liang , Li Gui Ling
Published: September 2011

The daily temperature change of a pavement structure has an important impact on its crack production and propagation. First of all, a one-dimensional transient mathematical model of heat conduction and a heat convection boundary condition that can take solar radiation and ground radiation into account were established according to the characters of the pavement structure and heat conduction. Secondly all the computational formulae were deduced for the above model utilizing SAM. Finally, the hourly temperature field of a typical pavement structure was calculated using ANSYS and SAM respectively. Results show that SAM solutions at different depths are in good line with ANSYS solutions. Therefore, SAM is an easy-programmed, fast and high precise method, and is deserve to be popular. In addition, the daily temperature changes at different depths were discussed, and some suggestions were provided for the thermal crack control and prevention of the structure
Experimental Study on the Wave Attenuation of Porous Pipe Breakwaters
Authors: Shih Ruey Syan
Published: September 2011

The dissipation of porous perpendicular pipe breakwaters are studied experientially in this study, the investigations on wave transmission of the porous pipe breakwaters are carried out in the laboratory with different wave conditions and various combinations of pipe diameter and length. The wave energy is mainly dissipated due to the drag and interception of the resultant motion by the pipe breakwaters, the reflectivity of such effect are thus discussed by the evaluation of partly reflected and transmitted ratio, and consequently the performance of the pipe breakwater for predicting wave transmission coefficient is investigated. Experimental results revealed that the attenuation is much effective with the decreasing of pipe diameter than increasing of the length.
The Research and Application on the Efficient and Local Accuracy Decrease Algorithm in Underground Engineering
Authors: Wang Wei Feng , Ye Jing Bin , Shi Sai Ying , Chen Qing Zhong
Published: September 2011

This paper studies the basic principles of finite element method, then researches on the core algorithm of finite element method, according to Saint-Venant principle, introduce the concept of composite element, proves that if the element is composite element, the original integration is still able to calculate. Based on the feature that numerical integration solution is in fact the Gaussian integration points are calculated, we endow element internal with different material property values according to the different location artificially. This is the efficient and local accuracy decrease algorithm. The algorithm is able to simplify the work of mesh generation, improve the overall computing efficiency, is especially suitable for underground engineering, and we can quickly get the overall characteristics of the structure that we are most concerned about. Finally, builds the actual examples of underground engineering, uses the finite element software Ansys and the efficient and local accuracy decrease algorithm program to calculate the actual examples respectively, compares the results between them, expounds and set the analysis theory and relevant principles, makes conclusion: the efficient and local accuracy decrease algorithm can simplify mesh generation, improve the overall computing efficiency; and it can be used in underground engineering very well.
The Prospect and Review of DEM Model Using in Saturated and Unsaturated Soil
Authors: Feng De Cheng , Zuo Wen Xin , Cao Peng
Published: September 2011

The saturated and unsaturated soil were widely studied by many researchers nowadays. With the development of calculation mechanics and computer, the discrete element method (DEM), as a powerful technique, has been implemented in saturated soil mechanics. This paper review the development of DEM and its application in saturated soil research. Meanwhile, it also prospect the application of DEM in unsaturated soil research. Besides, it also raised some problems that might be met in the real practice and it also tried to put forward some reasonable methods to solve these problems. In the end, this paper put forward a new DEM contact model based on the surface energy to analysis unsaturated soil.
A New Method to Test the Fracture Energy Based on Direct Tension
Authors: Zhao Zhong Hu
Published: September 2011

Fracture energy, which reflects the split property of brittle materials, is a significant parameter. For present tests of measuring it, the indirect test itself has insuperable disadvantage, while the direct tension test, in spite of an ideal way, is too limited to be widely applied in ordinary labs for its over high requirement for the test machine. The paper analyzed the disadvantage of the direct tension machine and improved it: a new elastic foundation of lower clamper replaced the original rigid one. Using the improved machine, the complete stress-strain tensile curve of the brittle materials was obtained easily. Further, the fracture energy could be calculated. Basing on studies, the paper recommended it may as well to get the fracture energy by improved direct tension machine.
Dynamic Behavior of Pile Foundation in Frozen and Thawing Soil
Authors: Li Hao , Lu Wei Nan
Published: September 2011

Permafrost is widespread in China, especially in Northeast China and the Qinghai-Tibet Plateau. Regions like Qinghai-Tibet Plateau have the most strenuous crustal movement. Therefore, earthquake-resistance of structures in permafrost region is an important issue. Furthermore, the permafrost will degenerate gradually as global warming mounts up. In some regions permafrost thickness tends to attenuate. Most bridge designs adopt pile foundation in order to reduce the effects of instable frost. The deterioration of frost leads to degradation of anti-seismic performance of bridges’ pile foundations. Pile-soil dynamic interaction numerical analysis models are established based on data of indoor low-temperature dynamic triaxial tests. Studies are performed on the dynamic stiffness and damping characters and the influencing factors of pile foundation under vertical harmonic load in frozen and thawing soil. The result shows that the dynamic response of the pile decreases along the depth, and the frictional resistance around the pile mainly distributes along the upper half of the pile, and the dynamic stiffness and damping of the pile are affected by temperature. Dynamic stiffness increases as temperature goes down, whereas the decrease of the temperature of frozen soil can notably lower the dynamic damping of the head of the pile. As the frequency of the dynamic load augments, the dynamic stiffness of the head increases marginally, whereas frequency has little influence on damping. The relative thickness of the frozen and thawing soil layer has considerable influence on dynamic stiffness, but negligible on damping.
Analysis on Geomorphology Change of Yangtze River Tributaries after the Impoundment of Three Gorges Reservoir - Set the Xiaojiang River in Chongqing China as Example
Authors: Hou Xin , Wang Kai , Wang Xiao Qing
Published: September 2011

After the impoundment of the Three Gorges Reservoir, geomorphology of the Yangtze River tributaries changed greatly. The Xiaojiang River in Chongqing is a representative tributary because of the unique local features on geographical conditions, hydrology conditions, migration and riparian zone. It is significant to explore and analyze the geomorphology change of the Xiaojiang River after the impoundment of the Three Gorges Reservoir for studying the feature of the Xiaojiang River channels. In this paper the geomorphology change law of the Xiaojiang River was calculated and analyzed based on the 2D Hydrodynamic and sediment models, and a few suggestions for protecting, developing and managing the Xiaojiang River are made from the conclusion of the analysis.
The Research on Calculating the Low Pile Foundation According to the Limitation State Considered the Interaction between the Soil, Pile and Irrigation Structure
Authors: Nguyen Van Loc , Nie Lei
Published: September 2011

Low pile foundation is spacious used to process irrigation structure. In Vietnam it is effectively used to process irrigation structure in the north plains. However, when calculating load of the foundation works, it was mainly calculated to transmit to pile omitted load transmit to surrounding soil, in fact the load was transmitted to surrounding soil. So the lager number of piles were used to process foundation, it caused waste of piles and economics. Therefor calculating pile foundation, as calculated the interaction interaction between Soil, piles and irrigation structure will reduce the number of piles in the foundation, and when the irrigation structures were deformation tested by software and measured in actual condition, the results showed that the irrigation structures were guaranteed to work as the normal design criteria. Now in Vietnam some of pump stations and aqueducts are applied the interaction between Soil, piles and irrigation structure to process foundation.
Bifurcation Analysis of a Network of Three Neurons with Time Delays
Authors: Mao Xiao Chen
Published: September 2011

The paper studies the dynamical behaviors of a recurrent neural network model consisting of three neurons with time delays through theoretical analysis and numerical simulations. The local stability of the trivial equilibrium of the network is analyzed and the sufficient conditions of the existence of Hopf bifurcation are given by discussing the associated characteristic equation. The direction and stability of the bifurcated periodic oscillations arising from Hopf bifurcation, which depend on the nonlinear terms of the network, are determined by means of the normal form and the center manifold theorem. Afterwards, numerical examples are performed to validate the theoretical analysis. The case studies of numerical simulations reach nice agreement with the theoretical results.
Prediction of Concrete Dam Failure: A Wavelet Approach
Authors: Li Qiang , Ren Qing Wen
Published: September 2011

The failure of concrete dam is a process started from local failure to global instability, and there is a huge scale difference in the process, so the analysis should be conducted in a multiscale manner. Choosing a typical failure curve as a signal, the precursor load is determined in the form of singularity point in the curve. With a numerical example, the previous reported methods for determining precursor load are compared with the wavelet approach, and it is shown that the wavelet approach gives more accuracy and reasonable results. Besides the precursor load, the failure mode, local failure or global instability, can also be figured out by the wavelet approach. By applying it to the Jinping arch dam, the obtained results are in good consistency with geology mechanical test. It is shown that the wavelet approach is of good applicability and accuracy for dam failure analysis.
Primary Research on the System Identification Method of Pitching Motion of Composite Trimaran
Authors: Zhu Feng , Yang Song Lin , Li Hui Lei
Published: September 2011

Abstract: The method of system identification has been initially applied in the field of the shipbuilding, especially in the application of the ship maneuverability.This article established the mathematical model of system identification of composite trimaran pitching motion model based on the genetic optimization algorithm, using VB language to write the recognition software, Design and produce a composite trimaran test model, doing the free pitching decay test ,then completing the pitching motion system identification according to the test data, and got the pitching motion equation which will be used to do the forecast ,the results of forecast can well match with the test results,confirmed the feasibility of this set of identification method, laid the foundation for other sway motion research of composite trimaran.
Damaged Plasticity Theory and its Application in Studying on Fractured Rock
Authors: Zhang Zhi Qiang , Li Ning , Chen Fang Fang
Published: September 2011

Fractured rock mass is one of the most important engineering materials for civil engineering in rock mass and rock layer, and has special failure model and constitutive relationship different from other man-made materials. A new numerical model is introduced and applied in studying the deformation, strength, and the failure mode of fractured rock mass, with the consideration of the damaged plasticity theory for intact rock, and joints distribution in fractured rock mass. A series of numerical experiments on jointed rock mass samples are performed to verify the validity of the new numerical model for fractured rock sample. Some feature datum from lab experiment is used to compare the results from numerical tests by the new model. According to these results, the initiation and propagation of induced fracture, and the failure mode of the fractured rock mass samples, are agreed with their associated feature datum by lab experiments.
Acceleration Discrimination of Stability and Reliability Analysis of Surrounding Rock of Loess Tunnel
Authors: Chen Si Yang , Li Zhong , Zhang Tian Yu , Ou Hua Wen
Published: September 2011

This paper analyzes the tunnel rock ultimate displacement,proposes using acceleration to determine the tunnel surrounding rock stability.Acceleration compared to determine the stability of surrounding rock ultimate displacement method obtained consistent results.Acceleration improved the ultimate displacement method to determine the shortcomings are difficult to quantify.Acceleration of rock deformation by the positive and negative judgments, rock deformation can clearly reflect the trends and status, you can clearly see which one works in a specific state of rock a dangerous warning signal.With a typical project examples validate the method used to determine the displacement acceleration stability of surrounding rock is accurate, feasible.Research and analysis to help build a tunnel surrounding rock stability analysis of the forecasting system.
Grey Model Theory Used in Prediction of Subgrade Settlement
Authors: Jin Sheng Ji , Zhang Da Sheng , Shu Zhe , Zhao Yun
Published: September 2011

In order to study the rule of highway subgrade settlement, both on-site experiments and theoretical analysis methods were used to analysis high fill embankment settlement. Gray model theory can be effectively forecasted the embankment of the different stages and the final settlement. According to the measured data of deposition tests, the comparative analysis of predicted results was carried out and some conclusions were drawn: 1) It is feasible that gray model theory is used to predict the settlement of the subgrade; 2) gray theory predictions adapt to these situations that similar information is less known, uncertainties and some rock deformation issues; 3)gray prediction accuracy is higher. The prediction model of GM established (1, 1) is reliable.
Research on Axial Magnetic Force and Rotor Mechanical Stress of an Air-Cored Axial-Flux Permanent Magnet Machine Based on 3D FEM
Authors: Cao Yong Juan , Huang Yun Kai , Jin Long
Published: September 2011

Due to its compact construction and high power density, the axial-flux permanent-magnet (AFPM) machine with coreless stator has obtained more and more attention and interest from researchers. For an AFPM machine with coreless stator, the axial magnetic attraction force may cause the rotors’ deflection and affect the machine’s reliability. In this paper, the magnetic field and the rotor mechanical strength of a coreless stator AFPM machine are studied. Finite-element method and analytic method are both used to calculate the axial attraction magnetic force between the two rotor discs. Structure finite-element analysis is used to simulate the maximum stress and deflection due to the axial magnetic force. The research is very significant to the power density elevation of the AFPM machine.
Simulation on Ceramic Composite Armors against Multi-Hit of APPs
Authors: Kong Xiao Peng , Jiang Zhi Gang , Liu Fei
Published: September 2011

The multi-hit of armor piercing projectiles (APPs) is one of the main treats to lightweight vehicles. Based on published ballistic experiments of Al2O3/Al2024 laminated composite armors against 7.62mm APP, the debonding of ceramic tiles was successfully simulated by setting reasonable material model and contact algorithm. A method named Geometric Intervals Method (GIM) was developed for simulation of multi-hit and its feasibility and rationality were investigated with the finite element code LS-SYNA. The numerical results shows that GIM has taken into account the effects of target damage caused by former APP impact on the target responds to later APP penetration. GIM can be used to simulate composite amours against multi-hit.
An Experiment on Bond-Anchoring Property of Prestressing Spiral Groove Tendon
Authors: Chen Meng , Guan Pin Wu
Published: September 2011

Prestressing spiral groove tendon is a new sort prestressing tendon, its characteristic value of tensile yield strength fyk=1000MPa. Firstly, the yield strength, ultimate tensile strength, elastic modulus and elongation are all tested. According to 68 pullout tests, the bond-anchoring curves and failure modes have been studied, and the effects of concrete strength, diameter, anchoring length, thickness of concrete cover and stirrup ratio have been all analyzed. Finally, the equation for ultimate bond-anchoring strength has been suggested by statistical regression, and the test results are in good agreement with values of the suggested equation.
Buckling Analysis of Soft-Core Composite Sandwich Plates Using 3D Finite Element Method
Authors: Kheirikhah Mohammad Mahdi , Khalili Seyyed Mohammad Reza , Fard Keramat Malekzadeh
Published: September 2011

In the present paper, an accurate 3D finite element model is presented for bucking analysis of soft-core rectangular sandwich plates. The sandwich plate is composed of three layers: top and bottom skins and core layer. Finite element model of the problem has been constructed in the ANSYS 11.0 standard code area. The effect of geometrical parameters of the sandwich plate is studied. Comparison of the present results with those of plate theories confirms the accuracy of the proposed model. The overall buckling loads calculated by FE model are higher than that of the accurate results and the maximum discrepancy is less than 10 percent.
Uniaxial Compression Tests Research on C35 Glazed Hollow Bead Insulation Concrete
Authors: Zhang Ze Ping , Qiao Fei , Wu Di , Li Zhu
Published: September 2011

With the growing global energy crisis, development of economic and land-efficient construction structural system became an significant subject in Civil Engineering field. Under this context, material and structural test and theoretical analysis research is meaningful on new energy-saving building material, glazed hollow bead insulation concrete. In this paper, one mix design that meet insulation requirements of the energy-saving project on coefficient of heat conductivity and compressive strength have been chosen. Under the uniaxial status, prism samples of above mix design have been selected to do compression strength and deformation tests; Systemic analysis of the relationship between the strength and deformation for glazed hollow bead insulation concrete has been carried through, and some results have been provided, including the stress-strain constitutive relationship of glazed hollow bead insulation concrete with grade c35, prism compressive strength, strain, initial elastic modulus, residual strength, ductility, etc.
The Design of Dynamic Vibration Absorber on the Engine of Fire Smoke Exhausting Robot
Authors: Fang Shu , Liu Sheng Peng , Liang Jing
Published: September 2011

The vibration of fire smoke exhausting robot affects a lot on running quality. The rotational speed of engine is fixed and the vibration of the robot’s engine has a certain dominant frequency, so a dynamic vibration absorber is possible to reduce the vibration. In this paper a typical structure has been designed, and the linear relationship between dominant frequency and engine speed has been surveyed. The elongation of the spring has been deduced to the only key parameter due to the linear relationship and determined speed. An evaluation standard of damping effect was set up, the maximum acceleration value and root mean square value of acceleration and relative value of acceleration were taken as the evaluation indexes. Comparison tests were made, the damping effect was taken into account. The experimental results demonstrate the practicability and effectiveness of the new simplified absorber.
An FBG Strain Sensor Demodulation Technique Using Temperature- Compensation HBF Sagnac LM
Authors: Huang Yong Lin
Published: September 2011

A novel method of a fiber Bragg grating (FBG) stain sensor demodulation technique is presented. An experimental system is built up in which high birefringence fiber (HBF) Sagnac loop mirror (LM) is used as the edge filter. In order to improve the temperature stability of the system, we have experimentally demonstrated that packaged HBF can compensate the temperature shit of the HBF Sagnac LM filter. The shift of wavelength for an uncompensated HBF Sagnac LM is approximately 2.3nm/0C, and that of the compensated HBF Sagnac LM is 0.03nm/0C, which is much less than that of the uncompensated HBF Sagnac LM filters. Using the temperature-compensation HBF Sagnac LM, We achieve linear demodulation of FBG strain sensor with a range of about 1900 and the strain sensitivity is about 0.14 w/ .
Real-Time Signal Processing Method for Infrared Sensor Arrays
Authors: Zhang Fu Xiang , Li Wen Zhong
Published: September 2011

Infrared sensor arrays is a new type of apperceiving system of robots, which are made up of large-area and flexible sensors with data processing capabilities. In order to meet the requirement of real-time obstacle avoidance, sensors which can be covered on the surface of robots were designed to apperceive the environment and provide the environmental information by the infrared sensors and the controlling circuit on them. To get rid of the environmental disturbance to the infrared sensors, and to meet the requirement of system precision, real time and stability, a kind of reconfigurable architecture based on DSP+FPGA was designed and a kind of spectrum analyzing method based on FFT (Fast Fourier Transform) was used. Tests of the system with different color papers as the measured subjects showed that the output of sensor arrays had low sensitivity.
Modeling on Hydrocyclone Separation Performance by Neural Network
Authors: He Feng Qin , Zhou Ping , Wang Jian Gang
Published: September 2011

A 17-27-5 type BP neural network model was built, whose sampled data was got by hydrocyclone separation experiments; another 6-30-5 type BP neural network was also built, whose sampled data came from the simulation results of the LZVV of a hydrocyclone with CFD code FLUENT. The two neural network models also have good predictive validity aimed at hydrocyclone separation performance. It demonstrates LZVV structural parameters can embody hydrocyclone separation performance and reduce input parameter numbers of neural network model. It also indicates that the predictive model of hydrocyclone separation performance can be built by neural network.
New Traffic Lights Identification Algorithms Based on Image Recognition
Authors: Shao You Lin , Chen Dao Jiong , Chen Long , Ni Wei Yu
Published: September 2011

The traffic lights identification algorithms is an important part of the platform for automatic driving technology and it is also applied in the remote control system. As the absolute standard of behavior instruction, lights are the most firsthand object to judge. Image recognition technology has been applied in the Gray Spaces and HSI space, but Comparing with RGB color space, the latter is easier to understand and realize. This paper puts forward a kind of identification algorithm for single or multiple lights. According to the target image numerical characteristics in the RGB color space and judging from the target area needed and the related parameters extracted, The feasibility of this algorithm is proved in theory and application and the experimental results are satisfactory in the Matlab environment.
A New High Speed Frequency Conversion Grating Torque Measurement System
Authors: Zhao Hao , Feng Hao
Published: September 2011

It is difficult to measure torque of high speed rotating machinery, a new mechanical structure torque sensor based on three phase asynchronous is designed, and combined with frequency conversion, a new frequency conversion Torque Measurement system is constucted. The sensor shaft and rotor are separated by bearing, for the accuracy of torque measurement, controlling frequency converter to make the speed difference of sensor shaft and rotor constant. This measurement system based on Filed Programmable Gate Array in signal processing, SCM in data processing and frequency converter controlling, and realize non-contract torque measurement. According to the results of the hardware test, indicated this measurement system is realizable. The good accuracy of measurement system is verified accord to the test, the fiducial error is .
Preliminary Result of Permafrost Roadbed Settlement Measurement Using Satellite D-InSAR Technology
Authors: Tan Qu Lin , Xie Chou
Published: September 2011

Monitoring ground subsidence of roadbed in permafrost region is very important for stability evaluation and safety management. To test its applicability to deformation monitoring for railway subgrade settlement in plateau permafrost region, satellite differential interferometric synthetic aperture radar technology (D-InSAR) has been applied to detect subgrade deformation in one test site along the Qinghai-Tibet railway with gathered interferometric SAR images. The preliminary experimental results showed that satellite D-InSAR technology can effectively acquire long-time deformation sequence through analyzing the ground scatterers with relative stable phase and are in accordance with the results obtained by conventional in-situ ground leveling. Along the Qinghai-Tibet railway in permafrost regions, it is found that settlement is the main behavior of subgrade deformation and the deformation amount of railway bridge is less than the sliced or the crushed rock embankment. It has very important engineering significance for state key infrastructure long-term monitoring system in plateau permafrost region.
Educational Resonator Gyro System Driven by Electro-Magnetic Force and Systems Engineering Process for Design
Authors: Jin Jaehyun , Rhee Huinam
Published: September 2011

This paper introduces a test system for resonator gyros for education. Two major purposes are to study the phenonmena of resonator gyros and to apply the systems engineering process for development. Resonator gyros have rich sources for engineering education: the Coriolis effect, resonating structures, vibrating mechanism, control algorithm, navigation, and so on. For the reasons, we have designed a resonator gyro system. We also have applied the systems engineering process for design: operational and system requirements are developed and those requirements derive architectural designs. A simulation program is coded by the LabVIEW to study the behaviors of resonator gyros.
Design of Experimental System for Corona Discharge in High-Velocity Airflow
Authors: Li Peng Fei , Zhu Zi Qi , Bai Fan , Chen Xi
Published: September 2011

Corona discharge is a kind of self-sustained discharge that emerges in daily life, industrial production and other fields. A variety of works have been done on this issue. And corona discharge in high-velocity airflow is of great significant especially. In this paper, an experimental system is proposed and assembled, to research the characteristics of corona discharge in high-velocity airflow and the differences between corona discharge with and without high-velocity airflow. By comparing simulation results of velocity field and pressure field of air amplifier and Laval nozzle, proper airflow supply device is selected. The experiment cabin is designed following the requirements of corona discharge to airflow by mathematical calculation. We also design the discharge device and receiving device by theoretical analyses. Experiments of corona discharge with and without high-velocity airflow are both done in the system. Significant distinctions showing the impact on corona discharge of high-velocity airflow is observed.
Time Discriminating Design for High Precision Pulsed TOF Laser Rangefinder
Authors: Shen Dong Qing , Chen Jian Yong , Li Wan Cai , Jiang Hong , Li Zhen Yu
Published: September 2011

The purpose of a time discriminator is to decide when the input is something you are interested in. It does this by putting out a logic pulse when the input signal meets an adjustable threshold value. A low cost high performance constant fraction discriminator (CFD) for laser rangefinder using pulsed TOF (time of flight) is proposed with the accuracy been improved. The theory of CFD is deduced and discussed and a distance measuring system has been established and experimental evidence is presented to show the feasibility of solving the time walking error problem to amend the precision and improving the environmental applicability, the distance error of +/-0.5mm was observed in the lab condition. The advantages of this instrument are highlighted and the experimental results are presented.
Research on Measure-Control Technology of Large-Span Suspendome during Construction Period
Authors: Wang Yong Quan , Guo Zheng Xing , Luo Bin
Published: September 2011

In order to ensure the prestress establishment of large-span suspendome, research on the measure-control methods for large-span suspendome during prestress construction process is performed, by summarizing the existing measure and test methods. According to engineering practice at present, the paper classifies the measure-control content of large-span suspendome during prestress construction period into two parts: internal force of cable-strut and deformation of steel structure. Taking practical project of a gymnasium as an example, the axial forces of hoop cables, radial steel tie rods and struts are measured, and also the verticality of struts. The test results are analyzed, and compared with the calculated value. The results show that, the internal forces of cable-strut and verticality of struts can both meet the design requirement, by mechanical analyzing and precise monitoring of the whole prestress construction process. The conclusion is that, before the prestress construction of large-span suspendome, construction mechanics analysis must be carried out in details to determine the control content and its target value, right measure-control methods are chosen, and then the effective establishment of prestress can be achieved.
Research of NC Machine Remote Monitoring System Based on Wireless Data Acquisition
Authors: Li Jin Hua
Published: September 2011

NC machine monitoring system is built based on the wireless data acquisition. All kinds of the complicated information can be collected, and the test server can process the information. Some important information can transmit by the network, and the client and web can browse them and feedback to the NC machine. The experiment was done on the system platforms, and basic functions were realized. It provides a new method that it can solve the key problem of the NC machine remote monitoring.
Study on Virtual Design of Positioning Fixture
Authors: Zhao Huai Bi
Published: September 2011

This paper investigates the typical positioning fixture design under a virtual environment. The modeling and assembling work of the fixture are firstly presented by CATIA V5. Then the static interference analysis and the dynamic interference analysis for the fixture are proceeded in the BUM module. Finally, the simulation is taken in the processing module to check the feasibility of the designed fixture. The presented research in this paper offers an engineering reference for positioning fixture design.