bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Welding Deformation of 304 Stainless Steel Plate with Different Thickness
Authors: Dong Liang , Zhou Chao Yu , Lin Cheng Xin , Chen Si Ying
Published: December 2013

The effect of processing parameters on the welding deformation of 304 stainless steel plates with different thickness were studied by using the pulsed Nd: YAG laser welding progress. Single factor experiment was used in this study. The results show that, in a certain range of parameters, the vertical deformation increases with the increment of the welding current, and decreases at the beginning and then increases with increment of the pulse duration and pulse frequency. However the increment rate of welding deformation decreases while the current value goes up. The welding deformation trends of the 304 stainless steels with different thickness stay the same in a certain range of processing parameters in terms of data collected from the experiment.
Evaluation of Stress Corrosion Resistance Properties of 15CrMoR(H) in H2S Environment
Authors: Wang Cui Cui , Wang Jing , Zhang Yi Liang , Li Yan
Published: December 2013

Tests including the constant load tensile, three point bending and hydrogen induced cracking (HIC) are executed to evaluate the comprehensive properties of the 15CrMoR(H) with new smelting process in saturated hydrogen sulfide (H2S) according to NACE and National Standard. By analyzing and fitting the results of constant load tensile test, the stress-life mathematical model of this material is given. Results show that the stress corrosion threshold of the constant load tensile is 0.7Rel (252MPa).The nominal stress of three point bending SC is higher than 4.5 Rel (1620MPa). Results of HIC test show that the crack length rate CLR is 4.40%, the crack thickness rate CTR is 0.87% and the crack sensitive rate CSR is 0.04%. According to EFC standard, the safety margin is 3.4, 3.4 and 37.5 times respectively. All the experimental results show that the 15CrMoR(H) material has excellent H2S stress corrosion cracking resistance properties.
Preliminary Study on Temperature Field of a Cylinder Circumferential Surface under Laser Spiral Scanning Quenching
Authors: Pan Zheng Xiang , Xu Hong Wei , Wen De Gang , Yan Long Fei , Zhou Sen
Published: December 2013

Laser quenching is an important heat treatment process which is used in many industries. It is necessary to ascertain the laser processing parameters before the process is performed. Therefore, a numerical simulation of the temperature field is a good way. This paper reports a numerical model for the temperature rise in the quenched zone of a cylindrical circumferential surface under laser spiral scanning quenching. In this method, the analytical solution is utilized of transient temperature field due to a moving point heat source. This model considers the effect of the adjacent quenched path on the base temperature of quenching performance and assumes a laser beam of a uniform intensity. The surface temperature field was computed based on the method. The analyses also indicate that the temperature at the later cycles area is much higher than that of the first cycles heated area. The practical value of this model will be a help for ascertaining the process parameters of laser spiral scanning quenching on cylindrical circumferential surface for an even temperature distribution.
Measurement and Correlation for Solubilities of 2,4-D Acid in Ethanol-Water
Authors: Wang Yan Fei , Hu Lin Shan
Published: December 2013

Within range of temperature from 15°C to 45°C,the solubility of 2,4-D acid in binary solvent formed from different ratio of ethanol and water are measured using equilibrium method.The results of experiment indicate that the solubilities of 2,4-D increase with the incresing temperature and the ratio of ethanol in mixed solvent.The solubility data are correlated with polynomial equation and semi-empirical equation.It shows the correlation with polynomial equation is better than with semi-empirical equation.
Catalytic Gasification of Lignin in Supercritical Water
Authors: Guan Qing Qing , Mao Tao Xiu , Miao Rong Rong , Chen Qiu Ling , Ning Ping , Gu Jun Jie , Tian Sen Lin
Published: December 2013

Lignin was gasified in supercritical water (SCW) with Ru/C, Pt/C, Pd/C and Ni/Al2O3-SiO2. The results indicated that the gasification yield (GY) and carbon yield (CY) were dramatically improved by four nano noble metal catalysts, especially with Ru/C, which doubled the GY and CY. The reason might be that catalysts can reduce lignin and help opening-ring, which lead to efficient gasification of lignin in SCW, but further research is necessary. Four catalysts have some different selectivity to different gases, but gaseous compositions are still similar as catalysis can’t change the reactions equilibrium.
Study on Cloud Data Destruction Mechanism and its Application
Authors: Wu Jing , Zhao Feng Zhi , Dong Yu Dan
Published: December 2013

The cloud data security is the primary concern users, especially in multi-tenant cloud environments residual data can cause data leakage problem, but most of the cloud service providers do not provide data processing residual solution. This study was designed HDFS multi-level security mechanisms and data destruction and data based on bidirectional heartbeat overwrite technology combined with the data from the destruction mechanism to ensure effective destruction of data under the premise of safety requirements and performance can be achieved demand balance.
Study on the Blood Flow with Rolling Manipulation of Traditional Chinese Massage
Authors: Tan Hui Li , Bai Ke Zhao , Kong Fan Rong , Jin Li , Li Hua Bing
Published: December 2013

A 2D model of a blood vessel under rolling manipulation (RM) is presented. The numerical simulations of blood flow are based on lattice Boltzmann method. It is found thatRMcan increase the blood flow. DifferentRMfrequency () has different influence on flow. When the frequency is equal to the pulsing flow frequency,the average flow over one period is the largest. Streamlines diagrams in different time when are given. Vortexes can be seen in the region under the stenosis. The distributions of streamlines change periodically.
Study on Test and Practical Application of Solidification Treatment of Wasted Mud
Authors: Chen Yuan , Wang Jia Can , Gao Hong Bo , Han Jian Gang
Published: December 2013

In the process of drilling and cast-in place pile, which usually produces a large amount of wasted mud. If the wasted mud had been mishandled, which may result in serious environmental problems. Combined with engineered examples, this paper mainly elaborates some common techniques related to the solidification treatment of wasted mud, the laboratory solidified test were done on the basis of the existed technical methods. The effect and cost of solidification treatment using different solidification agents were comparatively analyzed according to the result of test. Finally, in order to purpose of the optimal environmental and economic benefits, the suitable solidification treatment method and optimal mixture ratio are put forward to deal with the engineered problems.
Characters Analysis of the Retaining Structure of the Foundation Pit under Local Load
Authors: Xu Chang Jie , Yin Ming , Lin Gang
Published: December 2013

Taking one foundation pit engineering in Hangzhou for example, a numerical model of foundation pit under local load was established through the two-dimensional finite element software Plaxis. The influence on the displacements and bending moments of the retaining structure caused by construction process, the value and position of local load had been investigated. A simple discuss about local load' influence scope had been made. The results show that the displacements of row piles reach maximum after being excavated. As the values of local load increase or the distance between local load and foundation pit decrease, the status of the retaining structure becomes worse. Influence scope of load calculated in traditional method based on Rankine' theory may be rather small.
Experimental Study of Influence Factors in Unsaturated Soil Infiltration Rate
Authors: Cao Ling , Li Xin Zhe
Published: December 2013

Based on the unsaturated soil ponding water infiltration test in laboratory, the influences of cohesive particles content, dry density and initial water content on infiltration rate are analyzed. Soil infiltration rate decreased with the increase of cohesive particles content and dry density; with the decrease of initial water content at low dry density, and with the increase of initial water content at high dry density.
Hydro-Mechanical Coupled Analysis of the Variable Permeability Coefficient of Fractured Rock Mass
Authors: Zhang Yun Jie , Xu Tao
Published: December 2013

Based on the fluid-solid coupling theory, we describe the fractured rock mass as a continuous porous medium and consider the rock mass permeability coefficient a function of the stress and strain. By using the multi-physics coupling analysis software COMSOL, we achieved the dynamic change of permeability coefficient, and found that serious damage due to micro cracking occurred in the excavated damage zone of rock mass due to the yield and failure of rock mass. Corrodingly, permeability will remarkably increase, which is basically consistent with the experimental results. The simulations indicated the "indirect coupling" effect of seepage and stress. Therefore, the coupled analysis of the seepage and stress in fractured rock masses is important for the practical rock mechanics and rock engineering.
Analysis on Stress and Contact Failure of BNC Connector Components
Authors: Li Zi Yu , Liu Yan , Wang Sai Jin , Wei Wen Jian
Published: December 2013

As a main coaxial cable connector, BNC connector, internal connections of which often takes the form of a clamping structure, is widely used in communication industry. Due to different production processes and standards, inadequate compaction or out-of-tolerance component size in BNC connector production may cause poor contact, lead to mismatch loss and influence the quality of signal transmission. Based on an actual BNC connector failure, this paper analyzes mismatch loss caused by poor contact of its components, mainly focusing on excessive contact of its PTFE components. Quantitative analysis is given on the cause and sizes of mismatch loss, as well as stress distribution, which provides reference for coaxial cable production and troubleshooting.
Qualitative Calculation of Fatigue Life for Turbine Rotor Blade
Authors: Zhang Wei Fang , Tang Qing Yun
Published: December 2013

Fatigue fracture occurred on one blade when a certain aero-engine was under test run. The fracture is observed to measure the crack length and the average distance between fatigue striations. The Paris formula is employed to calculate the fatigue propagation life of the two main fatigue propagation regions observed on the fracture. The results show that the rate of crack propagation present a tendency of regular increase, and the fatigue propagation life takes a very small ratio of the total fatigue life of the blade.
Redistribution of Internal Force under Structural Defect and Non-Linear Spatial Stability under Live Load and Wind of Tied-Arch Bridge
Authors: Pu Qian Hui , Zhao Hu
Published: December 2013

To study the mechanical performance and stability of tied-arch bridge under structural defects and damages, limited element modal of Panzhihua Luoguo Jinshajiang Bridge was established and analyzed. Firstly, some typical damage models and their influence factors were presented. Then, based on the model established, change of suspender force caused by arch rib lineation defect, hanger lineation defect and boom failure was calculated respectively. The stability safety factor under the load group composed of dead load, live load and wind was calculated as well as the second-class nonlinear stability safety factor under structural initial defect. Calculation results shows that, suspender forces were more sensitive to archs vertical defect than to transverse defect. While, short hangers were more sensitive to lineation defect than long ones, and secondary inner force in short booms were bigger than in long ones. The result also tells that lateral wind is bad to lateral stability. Lift wind, somehow, makes positive contribution to structures in-plane stability. Structural initial defect can draw down the second-class stability safety factor under geometric nonlinear condition.
Research on CFRP Strengthening Corroded Reinforced Concrete Columns in Seismic Performance
Authors: Leng Ling Ye , Zhang Peng Fei
Published: December 2013

In recent years, CFRP is widely used both at home and abroad. The numbers of tests about the research on CFRP reinforcing corrosion concrete are more than numerical simulation. In this paper, OpenSees has been used to do the numerical simulation on nonlinear analysis of the CFRP reinforcement corrosion concrete column aseismic behavior. And the results were compared with the tests. The results show that it can well predict seismic performance of CFRP strengthening corrosion concrete by choosing reasonable material bond-slip constitutive.
Application of Modified Consistent Mode Imperfection Method in Stability Analysis of Single-Layer Reticulated Shells
Authors: He Sheng , Cai Jian , Liu Qi Qi
Published: December 2013

Based on the probability reliability theory, this paper proposes a modified consistent mode imperfection method, which fits the integral stability analysis of single-layer reticulated shells with the initial geometric imperfections. Nearly 1000 elasto-plastic load-deflection overall processes of four different rise-to-span ratio for Kiewitt-8 single-layer reticulated shells are analyzed by using the random imperfection mode method, the consistent mode imperfection method and the modified consistent mode imperfection method respectively. The study shows that the random imperfection mode method can assess the influence of initial geometric imperfections on structure stability more scientifically, but the calculation is quite large. By using the consistent mode imperfection method, the buckling load is not sure to be the most unfavorable, and the degree of reliability couldnt be ensured effectively. The modified consistent mode imperfection method can gain the buckling load which meets the requirement of probability reliability with less calculation. It can also assess the stability performance of single-layer reticulated shell structure more reasonably and safely.
Research of Rigid Pavement on Structure Combination of HMA Overlays
Authors: Liu Tao , Hu Guang Wei , Gu Ying Chun
Published: December 2013

To study the influence of structure combination on performance of rigid pavement hot-mix asphalt (HMA) overlays, four Hot-mix asphalt overlays are prepared for the research at the base of long-term performance of experimental roads. The results indicate that the SMA +AC+SMA sandwich structure can effectively restrain reflective cracking and rut. In addition, the structure can reduce the thickness and cost of pavement.
Dynamic Experimental Investigation on the Fundamental Frequency of Liquid Storage Tanks under Seismic Excitations
Authors: Liu De Yu , Fang Zhou
Published: December 2013

A large-scale earthquake simulation experiment about the unanchored cylindrical steel liquid storage model tanks has been completed. The fundamental frequency of the model tank with liquid inside was investigated based on the experimental data of the acceleration dynamic response. The seismic table test, the analysis methods are designed and conducted, and experimental results of the model tank were carefully measured. Furthermore, national design standard was used to calculate the fundamental frequency of the model tank system. The reasons for the existence of consistency and differences between the results obtained from experiments and national design standard were discussed.
The Application of Entropy Weight of Attribute Recognition Model in Reservoir Eutrophication Evaluation
Authors: Wu Du , Tang De Shan , Lu Xing Wang , Yu Wen Zhong
Published: December 2013

Subjective factors could affect the weight distribution of each index in evaluation of reservoir eutrophication, so the example used entropy to deal with the weight distribution of each index. Combined attributes recognition method, the writer selected six indicators to build the entropy weight of attribute recognition model about reservoir eutrophication of ten large reservoirs in Guangdong Province. By comparing the calculated results with the results of matter-element model, the calculation results were basically consistent. So entropy weight of attribute recognition model is applicable to the evaluation of the reservoir eutrophication and it can ensure the fairness and reasonableness of weight distribution.
Research on Finite Element Model for Parallel to Bamboo Culms Axial Shear
Authors: Fu Wan Si , Zhao Zhang Rong , Han Wang , Zhou Jin Bo
Published: December 2013

For the issues of bamboo structure safety caused by parallel to bamboo culms axial shear, shear capacity test method is studied, parallel to bamboo culms axial shear capacity finite element model based on brittle fracture mechanics is proposed in the work. The results calculated by FEM are consistent with the experimental results, and the error is in 16% or less. The parallel to bamboo culms axial shear capacity finite element model established above can provide supports for bamboo culms wide engineering applications. The developed model has theory and engineering significance for digital bamboo building optimal design.
CuOX Films for NO2 Detection: Microstructural Characterization
Authors: Myasoedova T.N. , Yalovega G.E. , Plugotarenko N.K. , Brzhezinskaya M. , Petrov V.V. , Moiseeva T.A. , Shmatko V.A.
Published: December 2013

Copper oxides films as promising materials for gas sensors applications were studied. Copper oxide films were deposited onto Si/SiO2substrates using a citrate sol-gel method with the subsequent temperature treatment at 150-5000C. These films were characterized by means of secondary electron microscopy (SEM) and X-ray-absorption near-edge structure (XANES) spectroscopy. The prepared films were utilized in NO2sensors. The dependences of the NO2response on the operating temperature and NO2concentration (10-200 ppm) were investigated. The maximum NO2response was achieved for the film annealed at 2500C.
Synthesis of Copper Nanoparticles at Room Temperature Using Hydrazine in Glycerol
Authors: Ong Huei Ruey , Khan Maksudur Rahman , Ramli Ridzuan , Yunus Rosli Mohd
Published: December 2013

Copper nanoparticles (CuNPs) have been prepared by the reduction of copper chloride in glycerol using hydrazine at ambient conditions. The reduction process takes place under vigorous stirring for 8 h. The formation of CuNPs and size were confirmed by UV/Vis analysis and TEM imaging respectively. The experiment result showed that, 7.062 mM of hydrazine solution and 0.0147 mM of Cu2+ solution were needed to synthesize narrow size monodisperseCuNPs.The presence of nanoparticle was found after an induction period of 4 h and further reaction time, complete Cu0 state nanoparticle was obtained as deep red wine colour was observed. Stability study of CuNPs showed that the nanoparticles were stable up to 4 days. The particle size of the nanoparticles have been analysed by transmission electron microscopy (TEM) and the average size of CuNPs was in the range 2 to 10 nm.
Studies on the Microstructures and Properties of Broussonetia Papyrifera Fiber
Authors: Zhang Tong Hua , Cheng Lan , Guo Min , Zhang Yuan Ming
Published: December 2013

The morphology and intrinsic properties are important factors in determining fiber processing technology and end-use performance characteristics. In this paper, a comprehensive study on structure and fundamental properties of the Broussonetia papyrifera fibers have been carried out. Morphological characteristics of Broussonetia papyrifera fibers were investigated using biological microscope and scanning electron microscope (SEM). Crystallinity and crystal structure were investigated by X-ray diffractometer. The fibers chemical components and degree of orientation were studied using infrared spectrometer instrument. Research results show that: Broussonetia papyrifera fiber possesses smooth surface and its cross striations are similar to ramies. Macromolecular crystallinity of Broussonetia papyrifera fiber is 80.57%, which is higher than that of many other natural fibers. Broussonetia papyrifera fibers orientation (65%) is close to but slightly worse than that of several other common natural fibers.This kind of fiber is Cellulose I and has almost the same components with ramie and cotton fibers.
Pattern Formation of Silicon Oxide Thin Film with InkMask
Authors: Ito Takuya , Ota Yasuyuki , Nishioka Kensuke
Published: December 2013

Patterned silicon oxide films were formed by a simple process using a dimethyl-silicone-oil as source and inks as patterning masks.After the coating of the ink, the dimethyl-silicone-oil was coated onto the substrate. The sample was heated at 150oC and ozone gas was irradiated. After the heat treatment with ozone gas, patterned silicon film was formed. The circle pattern with a diameter of 20 μm wassuccessfully formed.After the formation of the patterned silicon oxide film, the silicon oxide was hardly observed at the position where the ink coated.
Finite Element Analysis of Shear Behavior of Reinforced Concrete Beam Strengthened by High-Strength Steel Wire Mesh
Authors: Yang Chen Xing , Liu Zheng , Sun Li Ping , Li Jiong
Published: December 2013

Based on the experimental study of shear strengthened of reinforced concrete rectangular beam strengthened by high-strength steel wire mesh and polymer mortar , the finite element extended analysis was used. The finite element analysis software showed that with the increasing of the strand dosage and reinforcement strand length,the shear strength and stiffness of strengthened members improved . However,with the increasing of shear span ratio , the shear strength and stiffness reduced obviously .
MEMS/GPS Integrated Navigation System Based on EKF
Authors: Hong Lei , Li Ming Jian , Han Ning
Published: December 2013

MEMS (Micro-electromechanical Systems) sensors have many advantages including fast response, low cost, small size and low power consumption. However, MEMS sensors suffer low accuracy and poor stability due to the limitations of the manufacturing process. the MEMS/GPS integrated navigation system based on EKF make up for these shortcomings. The system using a low-cost MEMS sensor system consists of tri-axis gyroscopes and accelerometers which also incorporates a tri-axis magnetometer, and it can provide a complete measurement of orientation relative to the direction of gravity and the earths magnetic field.Extended kalman filter is used to fuse informations from MEMS and GPSof UAV. Mathematical models of GPS and MEMS sensor system are constructed based on matlab/simulink. The experimental results indicate that the average attitude angle error obtained is less than 0.15° in simulation experiments while position error is less than 7m and the velocity error is less than 0.4m.
Research on 3D Inspection Simulation Training System of 500kV Power Transmission Lines
Authors: Xiang Wen Xiang , Luo Hao , Hu Zhi Peng , Hu Hong Wei , Hu Chuan
Published: December 2013

Inspection work on power transmission line is an important link in the safe production of electric power, inspection staff training has always been attention of the power industry researchers. In order to improve learners training effect, we put forward a new form of teaching to inspect transmission lines with combined with simulation training. This paper analyzes the transmission line inspection requirements and the corresponding functions of the simulation system and the corresponding, then introduces the system structure, the abstract simulation training process, finally give the system application examples. Application results show that the 3D simulation training system of the power transmission line inspection can effectively guarantee training effect on the transmission line inspection technology.
Study and Apply on the Integrative Application of SBO and Business Intelligence
Authors: Wang Da , Luo Rong , Yin Sheng
Published: December 2013

Modern enterprise is facing some problems like how to achieve business intelligence information analysis on the basis of existing information systems as soon as possible, how to provide accurate and timely information support to decision-making and how to improve production efficiency. For these problems, this paper studies the existing ERP and business intelligence (BI) applications, put forward the viewpoint of integrating BI and ERP system. It designs the whole structure, Design ideas and development flow plans of SBO BI system. On this basis, we use a steel company in Chongqing as the background, build and analyze its sales-analysis model. It turned out that this scheme can effectively meet the requirements of enterprise based on information system for decision intelligent analysis.
Research on the Technology for DC CMT Welding of AZ31B Magnesium Alloy
Authors: Zhang Rui Ying , Hu Yun Yan , Wang Jun
Published: December 2013

Orthogonal experiment method was used on DC CMT welding of AZ31B magnesium alloy sheet. The tensile test was carried out on the CMT5305 microcomputer control universal testing machine .The effect regular of welding current, arc length correction and welding speed on tensile strength and elongation was analyzed and acquired the optimal combination of process parameters. That is, welding current is 62A, arc length correction is +30% and welding speed is 50cm/min. The microhardness test on joints was carried out. Its found that the curve of microhardness is "W" shaped and the micro-hardness of HAZ is minimum and that of weld zone is maximum.
Parametric FEM Analysis of Disc Brake
Authors: Chen Dong Fa , Ma Li , Guo Xue Xun , Zhang Qi
Published: December 2013

A parametric FEM analysis method is introduced for the design of disc brakes. The basic process of parametric FEM modeling is summarized, the FEM model of disc brakes is established. Finally, the parametric FEM strength and stiffness analysis are conducted for the typical disc brake assembly.
The Modified Iteration Method for Wet Cooling Towers to Calculate the Cooled Water Outlet Temperature
Authors: Wang Wei , Zeng De Liang , Hu Yong
Published: December 2013

Wet cooling towers are commonly used in thermal power stations to cool the condenser feed water. The temperature of cooled condenser feed water, which reflects the performance of cooling towers, has a great influence on steam turbine back-pressure and generation efficiency. Merkel Enthalpy Potential Equation is widely used to calculate the temperature of cooled condenser feed water. It is known to all that there is only one true value in nature; however, several solutions according with the equation appears. This paper provides the method to identify the true value of condenser feed water from several solutions, and finally puts forward its iteration calculating method, including the determination of the initial value and stopping rules.
Effect of Bolt Slippage and Joint Eccentricity on the Response of Lattice Structure with Non-Uniform Settlement
Authors: Zhang Hui Wu , Wang Peng , Chen Hai Bo
Published: December 2013

Lattice transimission towers are commonly made of angles bolted together directly or through gussets. And angle members are usually subjected to high axial force with eccentricity. Conventional structural analysis softwares solve such problems with the assumption of regarding the bolted connection as a rigid joint connection and ignored the effect of joint eccentricity. Thus the calculated internal forces of the structure members are bigger than those of real measurements, and the calculated structure deformation are smaller than the experimental ones under the same load. The main reasons for the discrepancy between the experimental results and the analytical solutions are bolt slippage and joint eccentricity. In this paper, the displacement-load curves of the bolted connections are introduced into the finite element simulation, revealing the effect of bolt slippage on the static response of lattice structure. The simulation results show that the bolt slippage causes the redistribution of the member internal forces of the lattice structure and increases the displacement of the lattice structure. The proposed algorithm and simulation results would provide good reference for further engineering applications.
Correlation between BMD & Radio Density of Human Bones for Strength Evaluation
Authors: Khan S.N. , Warkhedkar R.M. , Shyam Ashok
Published: December 2013

Radio Density of bones is measured in Hounsfield Units (HU) by a technique called as tomography, whereas the Bone Mineral Density (BMD) is measured by Dual-energy X-Ray Absorptiometry (DXA) scan. We aimed at finding correlation between BMD and HU of human bones for their strength evaluation.
Oil-Gas-Water Three-Phase Flow Monitoring Based on Image Fusion of ECT and ERT
Authors: Zhang Li Feng
Published: December 2013

Electrical resistance tomography (ERT) and electrical capacitance tomography (ECT) are sensitive to resistivity and permittivity distributions of the object to be imaged. However, it is hard to discriminate oil, gas and water phases only using ERT or ECT. In this paper, image fusion based on ERT and ECT reconstructed images was investigated for oil-gas-water three-phase flow. And then, pixel-based image fusion method was presented. Simulation results showed that the cross-sectional reconstruction images of oil-gas-water three-phase flow can be obtained using the presented methods for discussed cases.
Multivariant Optimization Algorithm for Multimodal Optimization
Authors: Li Bao Lei , Shi Xin Ling , Gou Chang Xing , Li Tian Song , Liu Ya Jie , Liu Lan Juan , Zhang Qin Hu
Published: December 2013

In this paper, a heuristic Multivariant Optimization Algorithm (MOA), which has the ability to locate multiple optima through alternating global-local search iterations by multivariant search groups including global exploration groups and local exploitation groups based on a structure where the optimizing process is saved, is described in detail. The performances of MOA are compared with that of other heuristic algorithms including GA and PSO based on six benchmark functions and the experiment results indicate that MOA outperforms GA and PSO in success rate and convergence efficiency on multimodal functions.
Remaining Life Prediction Based on HOLT Algorithm for Civil Aero-Engine
Authors: Bai Fang
Published: December 2013

Under the condition of limited information on route, incomplete check, minimum maintenance and other characteristics, it will be that the concept of reliability estimate extended to real-time application of reliability. The single remaining life prediction method based on HOLT algorithm to solve dynamic use under the environment of residual life prediction problem. Case analysis results show that the method of forecasting precision can get the engineering application requirements, so it is effective and feasible.
Optimization of Distributed Systems' Fusion Based on Climb-Ant Algorithm
Authors: Hu Xue Hai , Wang Hou Jun , Ren Dai Rong , Gong Cheng
Published: December 2013

This paper proposes an optimization algorithm which combines climb algorithm and ant algorithm and use it to solve optimization problems of fusion rules in distributed detection systems .Firstly, algorithm takes Bayes risk as the cost function, uses Climb-ant algorithm to optimize the sensors' decision threshold and Bayes criteria to solve the fusion rules of fusion center. Ultimately, we get the system's optimal (or suboptimal) fusion rules and realize the optimization of fusion rules in distributed detection system. Theoretical analysis and experimental results show that the new method has higher accuracy and efficiency of the solution than the traditional MAP (maximum a posteriori), SA-MAP, GA-MAP, and Coordinate Rotation Method.
Project Scheduling Problem with Stochastic Resource-Dependent Activity Duration
Authors: Zhong Chun Jie , Yu Ying , Jia Yun Lang
Published: December 2013

A resource-constrained project scheduling problem with stochastic resource-dependent activity durations is presented in this paper,and the two-point method is employed to simulate the uncertain property.Furthermore a genetic algorithm combined with this method is provided to solve the problem. Compared with the results from the genetic with Monte Carlo simulation, the proposed method is verified to be effective and more efficient.
Understanding of the Dynamical Properties of Machines Based on the Interpretation of Spectral Measurements and FRF
Authors: Dekýš Vladimir , Sapietova Alzbeta , Stevka Ondrej
Published: December 2013

s: The paper deals with understanding vibration source, transfer path and vibration of cover sheets by using tools of condition monitoring an experimental modal analysis, namely spectral analysis and frequency response functions. The measurements were selected specifically to an electromotor, a rotor, a shock absorber and the cover sheets and outputs measured were interpreted with regard to achieving the goal of reducing noise and vibration of machines. In this paper is presented using FRF functions as a useful tool for the interpretation of measured data.
Experimental Verification of the Properties of Fibres for the Mechanisms Based on Parallel Kinematic Structures
Authors: Václavík Jaroslav , Polach Pavel
Published: December 2013

The paper was written in the framework of research in mechanisms of the increased mobility on the basis of parallel kinematic structures, for which a fibre control instead of rigid elements is designed. The experiment is focused on the verification of the fibre properties in simplified mechanical systems such as motion on an inclined plane, vibration of a moving weight hanging on a fibre and fibre interaction with two types of pulley. The arrangement and instrumentation of the experimental stand and of the system for the measurement of position and axial forces in a fibre are described. The results should serve for tuning the computational model, the results of which are also presented in the framework of specific experiments.
Modal Parameter Estimation for Underdamped Linear Dynamic Systems
Authors: Nangolo Fillemon Nduvu
Published: December 2013

Modal parameter estimation is the estimation of frequency, damping ratio, and modal coefficients from experimental data. Modal analysis techniques are a common method used to determine these properties. The Least-Squares Complex Exponential (LSCE) and the Eigensystem Realization Algorithm (ERA) are one of the popular methods of modal analysis techniques. This paper presents an experimental verification of the LSCE and ERA methods. The investigation focuses on the estimation of natural frequencies, damping ratio and modal coefficients. To investigate this, artificial analytical data were processed in MATLAB environment to estimate the modal parameters. The identified vibration parameters from the LSCE and ERA were compared with the values based on classical dynamic theory, and the natural frequency and damping ratios percent of error were calculated.
System Inaccuracy Bolometric Components to Determine Elimination Procedures in the Process of Thermal Translocation Liver Living Biological Material
Authors: Ďuricová Lucia
Published: December 2013

Scientific document primarily describes the functionality of the principles of regression methods to determine the time of death and at the same time appreciating method used Henssgeho nomogram. Part of the document suggest application process statistically measurement in a process algor mortis and in the same time determining the measurement uncertainty of the process of translocation of material sensed temperature fields in the hepatic parenchyma. Evaluation of measured values for the determination of the correction factor of the material used there to define errors incurred in the process of research evaluation. Analyze the errors are drawn conclusions, leading to particularized elimination processes, which are used to determine the time of death polynomial regression method, and thus leads to propose strategic measures for practical application usage.
Influence of Aggregate Stiffness on Fracture-Mechanical Properties of Lime-Based Mortars
Authors: Tesárek Pavel , Nežerka Václav , Padevět Pavel , Antoš Jakub , Plachy Tomáš
Published: December 2013

Addition of relatively stiff aggregates into lime-based mortars is responsible for an increase of the effective mortar stiffness and stress concentrations around aggregates during mechanical loading. To observe the damage development during the three-point bending and splitting tests a 2D plane-stress nonlinear finite element analysis utilizing isotropic damage model was carried out and the results were validated against experimentally obtained data. The study revealed that the finite element model is able to capture the trends observed during the experimental investigation. The results of the numerical modeling and experimental investigation show the advantages of the use of relatively compliant crushed brick aggregates in ancient structures.
The Cement Paste Creep with Addition of Fly Ash in Time and Ratio of Parts 60/40
Authors: Padevět Pavel , Bittnar Petr
Published: December 2013

The article solves the comparing of the resize of cement paste creep with addition of fly ash in time. Creep was observed in the one monthly measurement for 4 and 10 months. The cement paste was prepared with fly ash in the ratio of the components 60/40 in favor of the cement components. Development of basic creep and creep was observed in water-saturated material. The measurement results are used as input data for the simulation of creep by the mathematical model and determine the values of the creep coefficient of cement paste. Results and comparison of q coefficients are presented.
The Use of Modan 3D in Experimental Modal Analysis
Authors: Huňady Róbert , Trebuňa František , Hagara Martin , Schrötter Martin
Published: December 2013

Experimental modal analysis is a relatively young part of dynamics, which deals with the vibration modes identification of machines or their parts. Its development has started since the beginning of the eighties, when the computers hardware equipment has improved and the fast Fourier transform (FFT) could be used for the results determination. Nowadays it provides an uncountable set of vibration analysis possibilities starting with conventional contact transducers of acceleration and ending with modern noncontact optical methods. In this contribution we mention the use of high-speed digital image correlation by experimental determination of mode shapes and modal frequencies. The aim of our work is to create a program application called Modan 3D enabling the performing of experimental modal analysis and operational modal analysis. In this paper the experimental modal analysis of a thin steel sample performed with Q-450 Dantec Dynamics is described. In Modan 3D the experiment data were processed and the vibration modes were determined. The reached results were verified by PULSE modulus specialized for mechanical vibration analysis.
Rail Vehicles Brake Components Test Bench Utilisation
Authors: Gerlici Juraj , Lack Tomáš
Published: December 2013

Reduction of noise due to rolling contact of wheel and rail for fright cars is one of the principal tasks of the European railways to be solved. Experts of railways, industries and universities were engaged during the last about ten years to search for technical solutions. An important noise reduction of fright cars can be achieved by replacing the cast iron brake shoes by composite brake shoes. Doing that, two directions have been taken into consideration. This is due to the fact, that at that time most composite brake shoes were based on friction coefficients were far away from that ones of the cast iron brake shoes. Applying such friction materials on existing vehicles would have as a consequence the change of braking forces acting on the wheels. These types of brake shoes (K-block) show a friction coefficient which is higher than that one of cast iron. As a consequence the application of the silent composite brake blocks of type K affords the adaptation of the braking system of the vehicle, what is cost intensive. For these reason, the application of K-brake block was proposed for new built vehicles. For existing vehicles solutions having the same friction coefficient as the cast iron brake shoes were requested (LL-Brake doing in this way, the modification of the braking equipment of existing fright cars could be avoided.
Deformation Properties of Laminated Glass Subjected to Increased Temperature
Authors: Bittner Tomáš , Tej Petr , Bouška Petr , Špaček Miroslav , Vokáč Miroslav
Published: December 2013

The shear interaction of laminated glass belongs to the essential characteristics of this material. The impact of the increased temperature on deformation properties was tested within investigation of basic mechanical properties of laminated glass panes. The specimens of laminated glass with the size of 120 x 1100 mm loaded by four-point bending load were exposed to the effect of the gradually increasing temperature up to approximately 65 °C in a thermal chamber. The progress of the deformation was continuously monitored by a measuring device during both temperature rise and subsequent cooling. Four kinds of interlayers were tested in total. In this paper the obtained experimental results are compared to numerical FE analysis and also the degree of an interaction of particular interlayer is evaluated.
Determination of the Necessary Geometric Parameters of the Specimen in Ring-Core Method
Authors: Menda František , Trebuňa František , Šarga Patrik
Published: December 2013

There are several measuring techniques for determining residual stress which can be divided according to the created damage in to the construction in non-destructive, semi-destructive and destructive ones. One of the most common is semi-destructive hole-drilling method. This paper deals about Ring-Core method which is based on the similar principles. Today, there is no standard for the Ring-Core method, thus it is important to consider various influential factors. One of them are the dimensions of specimen. Calibration coefficients are determined by finite element (FE) analysis using the commercial software Solidworks. These coefficients are used for residual stress evaluation by incremental method used in Ring-Core method. The influence of different specimen dimensions on the accuracy of the evaluated residual stresses is considered.
Influence of Air Content and Vibration Time on Frost Resistance of Air Entrained Concrete
Authors: Zheng Xiu Hua , Ge Yong , Yuan Jie
Published: December 2013

Air-entraining agent turely is one of the necessary compositions of the high durability concrete. The influence of air content and vibration time on the frost resistance of concrete was researched, and air void characteristics of hardened concrete was analysed. The results showed that the air contents could reduce the compressive strengthof hardened concrete excessively, but it made the spacing factor reduce obviously and significantly improve the frost resistance of concrete.The air voids with different structure in concrete were realized by vibration time. It was found that the air void structure and the frost resistance properties were influenced by the vibration time largely. The optimized vibration time is 30s, the appropriate vibration time is 20s~30s, no more than 35s.
Research on Early Cracking of the CRCP in the Tunnel under Low Temperature Difference
Authors: Liu Jian Wei , Zhao Dui Jia , Liu Shao Wen , Shen Jun Min
Published: December 2013

Calculate and analysis influence of the temperature field for Continuously Reinforced Concrete Pavement design. The temperature and crack of pavement are tested, so that the temperature changing and early cracks development inside the tunnel have been got. Studies have shown that: the tunnel temperature changes slowly, the temperature difference is small. In the first two days after concrete paving, the internal temperature of the slab was significantly higher than the ambient temperature, 79% of early cracking appears in this stages; Panel temperature rise because of the cement hydration. Strain increases in process of the growth of the concrete strength and shrinkage, the cracks appears. The number of cracks in the first two days accounted for 50% of the total number in 7 days, only the number of the second day accounted for 37.59%. Crack width accounted for 60.5% of the total, which is mainly concentrated in 0.1 mm and 0.2 mm. The crack spacing is mainly concentrated in 2m to 8m, accounted for 76.8% of all. The maximum crack spacing is 84 m, the minimum is only 0.5m.
Study on Freezing-and-Thawing Durability of Cement Concrete Based on Experimental Investigation of Air-Void Parameters
Authors: Zhang Jin Xi , Kong Xiang Jie , Wang Chao
Published: December 2013

This paper studies the freezing-and-thawing durability of cement concrete on the basis of experimental investigation of air-void parameters, which has a significant influence on the durability of concrete. More specifically, this research firstly discusses the effect of air-entraining agent types on the air-void parameters feature, and then a rapid freezing-and-thawing test is conducted to assess the durability of the concrete specimens, so as to observe the relationship between the frost resistance performance evaluation index, which is applied as durability factors in this study, and the air-void parameters of concrete, such as the air void spacing factor and the air content of cement concrete.
Concrete Strength Estimation Using the Maturity Method
Authors: Li Xue Feng , Fu Zhi , Luo Zhu , Li Sili
Published: December 2013

Two methods are used to estimate the concrete strength based upon the maturity concept. The conclusion is that the apparent activation energy E value is key factor in the equivalent age method, larger value of E indicated that the age conversion factor versus temperature function is more nonlinear, and an increase in temperature results in a disproportionate increase in the age conversion factor. It is also shown that there is a unique relationship between maturity and relative strength (ratio of strength to limiting strength), and the relative strength method method-can be used in the prediction for the concrete strength.
The Reason of Sign-Variable Thermoelectric Effect in Fe86Mn13C Alloy
Authors: Kveglis L.I. , Abylkalykova R.B. , Djes A.V. , Volochaev M.N. , Cherkov A.G.
Published: December 2013

The unique electrical and magnetic properties Fe86Mn13C alloy (Hadfild's steel) are due to special modulated structure. The alloy is widely used in mechanical engineering. Complex studies of the structure and properties of the alloy both in bulk samples and thin-films are suggested to describe the creation of a deformation martensite structure in Fe86Mn13C alloy in the form of self-assembled clusters. It is shown that combinations of anti-ferromagnetic austenite and ferrimagnetic martensite of deformation create unique electric and magnetic properties of Fe86Mn13C alloy both in bulk and in a thin-film state. We seek to explain the reason for the change of the sign of thermoelectric effect depending on temperature. Our task is to investigate thin Fe86Mn13C films as a possible solution to the problems of spintronics.
Design Optimization of an Industrial Muffler by Taguchi Method
Authors: Yang Ta Chung , Tsai Sheng Shian
Published: December 2013

A new muffler is designed to improve the noise emission of a 40HP Roots blower. The structural design of the muffler is discussed, including using glassfiber blankets of different densities for high-frequency noise, and multiple resonant chambers and microperforated plates for low-frequency noise. The noise of the discharged air stream of the Roots blower is significantly reduced from for 111 dBA to 78 dBA after installing the new muffler. Acoustic simulation on the muffler is performed and design optimization based on transmission loss is conducted using Taguchi method. ANOVA analysis, S/N ratios, and S/N curves are used to acquire the optimal combination of design factors.