bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical Assessment of Environmental Impact of Brine Discharge from a Desalination Plant on Coastal Water
Authors: Sun Jian , Yang Kun , Wang Hong Li , Li Wei
Published: July 2012

In North China, water shortage imposes constraint on economic and social development. Seawater desalination provides an effective approach to relieve this disadvantage, while this industry also accompanies with adverse environmental effects. To study the environmental impact of brine discharge from a desalination plant at the planning stage on the west coastal line of the Bohai Bay, the salinity distributions are predicted by using numerical simulation. Monthly variations of salinity distributions are given and the impacted areas are calculated. The results show that the mean area with salinity rising of 1 and 2 are about 40 and 10 square kilometers, respectively. The maximum impact areas are about 80 and 35 square kilometers respectively, which will take place in spring. The salinity variation at the inlet is predicted, which is fluctuated with the tidal oscillations, and the maximum salinity level is below 35 in this position.
Research on the Impact of the Water-Level-Fluctuation Zone on Landslide Stability in the Three Gorges Reservoir Area
Authors: Wang Hong De , Yang Qiang , Pan Shu Hua , Ding Wei Cui , Gao Yong Long
Published: July 2012

Taking the Lijiapo landslide in Three Gorges Area as an example, the study on the impact of seepage field changes caused by water level fluctuation on reservoir landslide stability was carried out. In order to find out the variation in slope stability when the reservoir water level changes at different rate, the stability calculation model was established adopting the Seep module and Slope module of Geoscience software GeoStudio, and calibrated with a long sequence of real-time monitoring data, based on the landslide survey data and test data. The results show that the reservoir landslide stability affected by the seepage field changes with changing reservoir level is controlled by a variety of factors, including the hydrodynamic pressure, hydrostatic pressure, uplift force, physical and mechanical properties (с, φ value change). When the water level fluctuates at a high rate, the impact of the seepage field changes on the stability is mainly affected by the pore water pressure before the stability reaches the extremum, while after the extremum, with the further infiltration or drainage of reservoir water, it is mainly affected by the change of physical and mechanical properties. When the water level fluctuates at a lower rate, the pore water pressure, uplift force and physical and mechanical properties are the dominant factors.
Experimental Study on Dynamic Consolidation Method to Improve Saturated Soft Soil Foundation
Authors: Du Guang Qian , Zhu Chang Zhi , Zhang Xi Ping
Published: July 2012

A new technology of dynamic compaction method is successfully used to reinforce the saturated soft soil foundation. The field monitoring laws of lateral displacement of the foundation after dynamic compaction, the increasing and dissipation regularity of the excess pore water pressure are analyzed and discussed. The improvement effect is verified by static cone penetration test and loading test. The determination methods of effective reinforcement depth after dynamic compaction are put forward. The practice shows that, by field-testing methods, such as static cone penetration test and pore water piezometer test, to determine the effective reinforcement depth after dynamic compaction and other design parameters is reliable.
Comparative Study on Settlement Prediction of Railway Subgrade on Collapsible Loess Area
Authors: Ma Xue Ning , Wang Xu
Published: July 2012

The settlement prediction is an important problem to railway subgrade design and construction in the collapsible loess region. Prediction of subgrade settlement is more methods through measured data in practical engineering. Based on the long-term monitoring data of settlement of loess subgrade at Lanzhou-Wuwei second-railway line, a new prediction model was put up and contrasted with other models such as Hyperbolic model, Logarithm model, exponential model and Poisson’s model. The results showed that the new model could be better predict settlement laws of loess subgrade, and agreed well with hyperbolic model forecast results, and proved the correctness of the model.
Analysis of Vertical Bearing Capacity of Single-Row Pile Group of an Offshore Platform
Authors: Zhuo Rui Hua , Liu Run , Wu Xin Li , Zhao Yang Yang
Published: July 2012

The vertical bearing capacity of a special pile group of platform in an offshore gas field has been studied. Large diameter d (2.134 m), deep penetration l (96 m), small spacing sa (3.507 m), and only one row piles are the usual characteristics of the pile group foundation in offshore engineering. According to the requirements of the related design code, the super pile group effect has to be considered. However, with the usual design code, when sa/d, the ratio of spacing to diameter, is less than 2.0, there is no way to consider the pile group effect. In this paper, considering the occlusion effect of soil plug of pipe pile, several methods have been introduced to study the super pile group effect of the vertical bearing capacity. These methods include linear elastic theory method, the method recommended by the Code of Pile Foundation in Port Engineering (JTJ254-98), and the method with virtue of the existing pile group model test results. Meanwhile, the plugged and unplugged conditions have been considered, respectively. Through the analysis, the factors of safety in extreme and normal operation states are obtained, and the results satisfy the design specifications.
Numerical Simulation of the Elastic Field Nearby the Source and its Data Analysis
Authors: Liu Wei , Wang Xiao Zhe
Published: July 2012

In the source region, numerical simulation usually has a bad result. So, a two-dimension point-source FDTD simulation has been completed in this paper. By analyzing the data nearby the source, some results are gained. In the source region, for its own characteristic of FDTD, reflect waves’ reaching time doesn’t agree with its expectation in theory. But the data can be corrected by counter deduction. As an application, a level interface inversion is done by using the corrected data and a good result is obtained.
Numerical Study of the Influence of Interlayer Mechanical Properties on Salt Cavern Storage Stability
Authors: Huang Xiao Lan , Yu Chao , Ma Hong Ling
Published: July 2012

Numerical and experimental studies including different soft and hard layer thickness were conducted under different pressures for analyzing the effect of interlayers on stability of salt cavern considering shrinkage rate, plastic zone and displacement vectors. The results indicate that: Cavern shrinkage rate is increased appreciably with increased of soft layer thickness and decreased significantly with increased of hard layer thickness. The plastic zone change is not obviously with increased of soft layer thickness but obviously with hard layer and plastic zone are significant differences at layer while cavern including soft layer and hard layer, the soft layer effect on plastic zone is less than hard layer and it is more sensitive to pressure increasing, the fracture of hard layer is more easily than soft layer. Maximum displacements happen at layer while cavern including soft layer and at salt rock while cavern including hard layer. Comprehensive differences effects of soft layer and hard layer to stability of salt cavern storage find that fine hard layer and heavy soft layer are more unfavorable. The results are important to oil-gas storage cavern modeling analysis in laminated salt rock.
Study on the Evaluation Method of Subgrade Settlement Caused by Structure Layer of the High-Speed Railway
Authors: Jiang Ling Fa , Xiong Shu Dan , Xu Xi Chang , Chen Shan Xiong
Published: July 2012

Based to the geometric and mechanical parameters of the typical high-speed railway, the settlement values on the foundation and the subgrade face with different structure layer load are obtained by the numerical calculation. According to these numerical results, the power functional relationship between Sst / S∞ and Pst /hγ is found, and a new evaluation method of the subgrade face settlement caused by the structure layer using the measure data is put forward. Through analyzing the settlement data of different conditions, the parameters of the formula are discussed, and some conclusions and suggestions are given. This new evaluation method will provide some reference for the design and the evaluation of the subgrade settlement caused by the structure layer of the high-speed railway.
Study on Triaxial Creep Experiment of Beishan Granite under Low Confining Pressures
Authors: Ma Li Ke , Li Yun Feng , Zhao Xing Guang
Published: July 2012

Time-dependent brittle deformation is a foundational process operating in the underground engineering. So, the study of its characterization is essential to the design and construction of excavations in the rocks for high level radioactive waste disposal repositories. In this study, three constant stress tests under different confining pressures were performed on specimens of Beishan granite. Based on the laboratory results, we investigated mechanical creep behavior of Beishan granite under low confining pressures and compared the results with previous investigations.
Determination of Ultimate Filling Height of Slag Subgrade with FEM Modelling
Authors: Zhan Bing Gen , Ruan Yi Dong , Han Ding
Published: July 2012

To use slag in high subgrade reasonably and effectively, the filling height limit was investigated. The viscoelasticity parameters of slag in a ascertain graduation were gained by viscoelasticity constitutive model and indoor creep test. The differential settlement values (DSV) of subgrade surface at various filling heights were obtained by the finite element modelling. The research results show that the DSVs on subgrade surface increase with the filling height. According to the effects of DSV on pavement structures, four grades of differential settlement from low to high were divided, the ultimate filling heights of slag were evaluated correspondingly.
The Numerical Solution of Richards Equation Using the Lattice Boltzmann Method
Authors: Liu Ning Ning
Published: July 2012

The Richards equation is applied to describe the unsaturated soil moisture movement. The Lattice Boltzmann method is developed to solve this partial differential equation. The accuracy and efficiency of the Lattice Boltzmann method in modeling unsaturated soil moisture movement are compared to the Philip series method as well as Crank-Nicolson finite difference scheme. The results reveal that all three methods provide solutions of comparable accuracy. The computation efficiency, accuracy and simplicity of the Lattice Boltzmann method indicate that it has the capacity to model unsaturated soil moisture movement.
Solving the Flexible Job Shop Scheduling Problem Based on Memetic Algorithm
Authors: Zhang Guo Hui
Published: July 2012

Flexible job shop scheduling problem (FJSP) is a well known NP-hard combinatorial optimization problem due to its very large search space and many constraint between jobs and machines. Evolutionary algorithms are the most widely used techniques in solving FJSP. Memetic algorithm is a hybrid evolutionary algorithm that combines the local search strategy and global search strategy. In this paper, an effective memetic algorithm is proposed to solve the FJSP. In the proposed algorithm, variable neighborhood search is adopted as local search algorithm. The neighborhood functions is generated by exchanging and inserting the key operations which belong to the critical path. The optimization objective is to minimize makespan. The experimental results obtained from proposed algorithm show that the proposed algorithm is very efficient and effective for all tested problems.
R&D Investment on Alternative Fuel Vehicles: Insights from a Two-Stage Game Theoretic Model
Authors: Chi Chun Jie , Ma Tie Ju
Published: July 2012

The R&D on alternative fuel vehicles has gained increasing attention by companies. In this study we develop a two-stage game theoretic model to explore the cooperative and noncooperative R&D activities in alternative fuel vehicles with spillovers. The results provide practical insights into actions that could be considered by regulators and organizations to encourage environmental investments.
A Fuzzy Linguistic Go/No-Go Decision Model in New Product Development
Authors: Yan Hong Bin , Ma Tie Ju
Published: July 2012

New product development~(NPD) is a quite risky and uncertain process. In order to reduce the risks and uncertainties, the firms need to evaluate their new product at each step carefully and make accurate decisions. This paper focuses on uncertain go/no-go decisions in the NPD process. To do so, a probabilistic approach is firstly proposed to elicit a probability distribution of the gate-team's judgement. Secondly, a probabilistic approach is proposed to perform group and multicriteria aggregation with the random interpretation of group weights and criteria weights.
On Uncertainties of Kansei in Kansei Engineering: A Fuzzy Linguistic Approach
Authors: Yan Hong Bin , Ma Tie Ju
Published: July 2012

Kansei Engineering~(KE) has been developed as a methodology to deal with consumers' subjective impressions and images of a product into the design elements of a product. One central step amongst KE is to generate the Kansei profiles of the products. Kansei is a quite subjective, ambiguous, and uncertain concept, which is frequently represented in linguistic forms. Toward this end, this paper tries to cope thoroughly with the uncertainties of Kansei in KE. A probabilistic approach is proposed to generate Kansei profiles involving the ``individual" uncertainty, ``group" uncertainty, and the partial semantic overlapping of Kansei. Our approach results with a probability distribution on a set of linguistic Kansei labels.
Modeling of Fatigue Crack Closure by Finite Element Method
Authors: Ding Zhen Yu , Wang Xiao Gui , Gao Zeng Liang
Published: July 2012

Crack closure concept is often used to explain the crack propagation behavior in cracked components. The effective stress intensity factor range is considered as a driving force of fatigue crack growth based on the traditional crack closure concept. The crack closure process and the plastic deformation near the crack tip were discussed in this paper. The standard compact tension specimen with the plane-stress condition was used to study the crack closure. A dynamic crack propagation method was proposed to simulate the effect of previous fatigue crack growth on the successive crack growth behavior. To obtain the accurately numerical results of stress and strain components, the Jiang and Sehitoglu cyclic plasticity model was implemented into ABAQUS as UMAT. With the detailed stress and strain response taken from the finite element (FE) simulation, the whole process of crack closure was described by the load curve. The load corresponding to maximum crack closure length is firstly proposed to describe the effect of fatigue damage. According to the results of FE simulation, the cyclic plasticity of the material near the crack tip persists during the crack closure period and should not be ignored.
Study on Influencing Factors on Reliability of Permanent Magnet Synchronous Motor System in Electric Vehicle
Authors: Yang Kai Li , Song Qiang
Published: July 2012

In this paper, based on the working environment and characteristics of PMSM system in EV, the influencing factors and their action mechanism on the weak links with high failure rate are analyzed, concluded from the failure modes of PMSM system in EV. Temperature, as the most influential factor, is emphatically studied, combined with the related test results. The action mechanism of temperature on some typical components (winding insulation, bearing, permanent magnet and IGBT) is studied in detail, laying a foundation for further reliability expectation and test. This indicates that PMSM reliability can be tested and enhanced from its working temperature.
Projection Model of Intuitionistic Fuzzy Multiple Attribution Decision Making about Preventive Maintenance Modes in RCMA
Authors: Cheng Jun Wei , Zhang Guo Bin , Liu Xu Gang , Wang Chao
Published: July 2012

In order to increase the validation of preventive maintenance modes decision generally gotten by analyst’s subjective and qualitative judgment in reliability-centered maintenance analysis (RCMA), a projection model of intuitionistic fuzzy multiple attribution decision making for preventive maintenance modes in RCMA was presented. An illustration was used to validate the model of decision making about preventive maintenance modes in RCMA for vehicle equipment. The results indicate that the model is suitable to select the optimum preventive maintenance mode. Compared with the fuzzy comprehensive model that describes fuzzy information only by degree of membership, the intuitionistic fuzzy model more precisely and entirely describes fuzzy information come from RCMA by degree of membership, non-membership and hesitation. Then it is more adequate in group decision making for RCMA. It may be used in developing decision support system for RCMA.
The Simulation of the Ship Production Design Process Based on Hierarchical Timed Petri Net
Authors: Yan Rui , Jiang Ping , Li Wei Jia , Yan Jun , Wen Long
Published: July 2012

Shipbuilding is a very important industry for its irreplaceable role into the sea transport and oceans exploration. But ship production design is a very complex process, causing the inefficiency of the shipbuilding. At the same time, the current situation of most shipbuilding enterprises is the multi-project environment and the resources among them are shared, the large and complex systems are hardly to simulate. In this research, a multi-resources oriented hierarchical timed petri net (HTPN) are constructed to model the ship production design process under the multi-project environment and a WFPN software is developed based on HTPN. To evaluate the efficiency and applicability of WFPN, a case study is conducted and the results show that it’s practicable. Beside on it, the analyses of the resource loads are also providing a way to promote the efficiency of the shipbuilding enterprises.
Intelligent Irrigation System Reliability Simulation
Authors: Yu Song , Ao Chang Lin , Chen Hong Guang
Published: July 2012

This paper presents the composition and working principle of a intelligent irrigation system, and studies the reliability of system. It analyzes the system's failure modes. It establishes the system simulation model by using fault tree analysis, and it uses Monte Carlo method to carry on reliability simulation. The simulation results are given. Some suggestions on improving and perfecting the system are put forward based on the results. The conclusions provide a reference for reliability and maintainability of intelligent irrigation system. It is of great significance to increase agricultural production.
Strength and Reliability Analysis of Hydraulic Support
Authors: Ma Yuan Yuan , Xie Li Yang , Qin Xiao Feng
Published: July 2012

Hydraulic support is an important equipment of synthesis mechanization caving coal and safe production in modernization coal mine. According to the research object of ZF5000/16/28’s mould hydraulic support, stress distribution of dangerous parts is obtained by stress testing and ANSYS software. The relevant total displacement distribution rule and equivalent stress distribution rule of the type hydraulic support prototype were found. At the same time, reliability analysis of a single stent and stent system reliability prediction were carried out, which guides design and use of hydraulic support in theory better.
Research of the Thought and Method in Function Reserving Design Based on Individuation Degree Evaluation
Authors: Li Chun Fu , Ye Ze Qun , Wang Yu Hui , Feng Xian Min
Published: July 2012

Thought and method in function reserving design is for realizing the volume-production of individual products, based on the attention of users' individualities. The function tree is built up according to the subdivision of the total function. On this foundation, the method requires all the leaves of the function tree evaluated on their individuation degree by calculating the opening degree, association degree and dependency between the factors and the intimacy and interest degree between function factors and users. According to the result of individual degree evaluation, a rank of individuation degree priority of them is listed to help to decide the proper factors to reserve. By this means, users can participate themselves into the procedure of design, meeting their own individual needs.At last of this paper, the realizability of the thought and method is statemented and a case of lamp design of this method is taken as an example to demonstrate the design procedure.
Optimal Design of the Large-Diameter Spinning Torispherical Head
Authors: Zhang Di , Sheng Shui Ping , Gao Zeng Liang
Published: July 2012

Two important parameters of torispherical head that are (interior radius of spherical crown area) and r (interior radius of transition corner) have been optimized by the module of the large general-purpose finite-element software ANSYS, targeting the strength and stability of the head. This paper provides an optimized torispherical head, which improves the stability of the edge of the head with acceptable strength of the head. The procedure is generally applicable as a design tool for optimal design.
A Design Space Exploration Method Using Artificial Neural Networks and Metamodeling
Authors: Chi Li , Qiu Hao Bo , Chen Zhen Zhong , Ke Li
Published: July 2012

This paper suggests a design space exploration method using Artificial Neural Networks and metamodeling to systematically reduce the design space to a relatively small region. This method consists of three major steps. Firstly, self-organizing maps is employed to analyze design variables and objective function(s) with the original samples as preliminary reduction optimization of the initial large design space. Successively, resampling within the preliminary reduction space, clustering sample points using the fuzzy c-means clustering method with the given number of cluster, and choosing the most attractive cluster to construct kriging model and identify the design optimum within the reduced design space in the last step. The accuracy and validity of proposed methodology is proved by a heat exchanger design problem. It is found that the proposed method can intuitively capture promising design regions in which it is efficient to acquire the global or near-global desigm optimum.
Engineering Design Based on Hammersley Sequences Sampling Method and SVR
Authors: Ke Li , Qiu Hao Bo , Chen Zhen Zhong , Chi Li
Published: July 2012

Nowadays, computer-based engineering design is becoming widely used in the design of products. In the field of engineering, CAD model, FEM method and surrogate model are used to reduce the time and computational cost comparing with the traditional engineering design. But when facing with computationally expensive tasks, such design method mentioned above seems unable to deal with such tasks. In that case, surrogate model is gradually used and shows great potential in dealing with the computationally complex tasks. Although computing power and speed are rapidly growing, the use of the computer simulation analysis is limited in doing engineering design and some other analysis such as reliability analysis for complex product, so that it limits the use of metamodeling techniques. In that case, we use space-filling DOE sample method to support the construction of surrogate model. In this paper, we consider both Hammersley sequences and SVM as sampling method and surrogate model to construct the simulation design model, aiming at reduce computational costs. SVR achieves more accuracy and shows great potential in application in the design of complex and computationally expensive tasks.
Reliability Analysis Method Based on Support Vector Machines Classification and Adaptive Sampling Strategy
Authors: Hao Hong Yan , Qiu Hao Bo , Chen Zhen Zhong , Xiong Hua Di
Published: July 2012

For probabilistic design problems with implicit limit state functions encountered in practical application, it is difficult to perform reliability analysis due to the expensive computational cost. In this paper, a new reliability analysis method which applies support vector machine classification(SVM-C) and adaptive sampling strategy is proposed to improve the efficiency. The SVM-C constructs a model defining the boundary of failure regions which classifies samples as safe or failed using SVM-C, then this model is used to replace the true limit state function,thus reducing the computational cost. The adaptive sampling strategy is applied to select samples along the constraint boundaries. It can also improves the efficiency of the proposed method. In the end, a probability analysis example is presented to prove the feasible and efficient of the proposed method.
The System of Signal Detection Based on Sensing Needle
Authors: Lei Jian Ming , Zeng Xiin , Zou Xue Cheng
Published: July 2012

Biologic systems frequently have electric activity associated with them. This activity can be a constant dc electric field, a constant flux of charge-carrying particles or current, or a time-varying electric field or current associated with some time-dependent biologic or biochemical phenomenon. The mechanism of electric conductivity in the body involves ions as charge carriers. Thus, picking up bioelectric signals involves interacting with these ionic charge carriers and transducing ionic currents into electric currents required by wires and electronic instrumentation. Calcium ion is so important in our body, which plays a crucial role in metabolism.The common methods of detecting calcium ion include radioactive tracer method, activation shine protein method, etc, we choose calcium ion sensing needle as a tool to detect the calcium ion in the acupoint.
A Reliability Index Based Decoupling Method for Reliability-Based Design Optimization
Authors: Chen Zhen Zhong , Qiu Hao Bo , Hao Hong Yan , Xiong Hua Di
Published: July 2012

Reliability-based design optimization (RBDO) evaluates variation of output induced by uncertainties of design variables and results in an optimal design while satisfying the reliability requirements. However, its use in practical applications is hindered by the huge computational cost during the evaluation of structure reliability. In this paper, the reliability index based decoupling method is developed to improve the efficiency of probabilistic optimization. The reliability index is used to calculate the shifting vector in the decoupling process, due to its efficiency in evaluating violated probabilistic constraints. The computation capability of the proposed method is demonstrated using two examples, which are widely used to test RBDO methods. The comparison results show that the proposed method has the same accuracy as the existing methods, and it is also very efficient.
The Multi-Objective Oriented Product Design Method in the Machine Tool
Authors: Li Wei Zhan , Yang Xian Ying
Published: July 2012

The Large-scale Laser Process Center (LLPC) is a type of Machine Tool (MT). With the LLPC as a sample, this paper analyzed the systemic factors of the MT product, built the Multi-Objective(MO) system impacting on the product design results, with the requires of MO proposed a integrated design method with a Frame Structure(FS), applied on the practical design of LLPC. By the verification from the process controlling and reality product, proved the expectation and the value of this method. It gave a reasonable guide for the structural design and cleared the product design confused stage, improved the design efficiency and the image quality of MT product, and indicated the main design process line in the product development.
Equipment Performance Degradation Modeling for Reliability Prediction Based on n-ARIMA Model
Authors: Wu Jun , Deng Chao , Xiong Huan , Xiong Yao
Published: July 2012

Performance degradation; Time series; Reliability prediction; Non-stationary data. Abstract. Performance degradation model has become a critical issue for lifetime reliability research. A novel n-ARIMA-based equipment performance degradation model method was proposed in this paper. First of all, a general performance degradation process was analyzed in detail. Then a non-stationary Auto-Regression Integrated Moving Average model was adopted to set up the equipment performance degradation model, and an equation to calculate the performance degradation level was also built. Finally, a validation experiment was implemented on OTM650 milling machine. It has been indicated from the experiment that the performance degradation model built in this paper may accurately describe the characteristics of the equipment performance degradation against time.
Research on the Logistics Distribution under the Electronic Commerce Environment in Henan Province
Authors: Shi Ying
Published: July 2012

The logistics distribution under the electronic commerce is becoming the vanguard of innovation in circulation filed, representing the main direction of modern marketing. A large number reference about electronic commerce logistics distribution were studied. In this paper, effective countermeasures are proposed for the electronic commerce in Henan Province, through analyzing the impact of various factors in the efficiency of logistics such as information technology and analysis methods of logistics distribution. studies a large number of e-commerce logistics and distribution industry in Henan Province.
Using the Memetic Algorithm for Multi Objective Job Shop Scheduling Problems
Authors: Zhang Guo Hui
Published: July 2012

The multi objective job shop scheduling problem is well known as one of the most complex optimization problems due to its very large search space and many constraint between machines and jobs. In this paper, an evolutionary approach of the memetic algorithm is used to solve the multi objective job shop scheduling problems. Memetic algorithm is a hybrid evolutionary algorithm that combines the global search strategy and local search strategy. The objectives of minimizing makespan and mean flow time are considered while satisfying a number of hard constraints. The computational results demonstrate the proposed MA is significantly superior to the other reported approaches in the literature.
Method for Determining the Reliable Life Parameter of Turbine Wheel of Turbocharger with Over-Speed Failure Mode
Authors: Wang Zheng , Wang A Na , Guo Kai , Zhuang Li , Hua Lin
Published: July 2012

For the over-speed failure mode, the method for determining the reliable life parameter of turbine wheel of turbocharger is proposed in this paper. The shortage of design criteria based on conventional safety factor for turbine wheel with over-speed failure mode is analyzed. In order to embody the characteristics of structure and over-speed failure mode, the turbine wheel is taken as a series system consisting of several blade symmetrical components in the reliability modeling process. The time-reliability models of turbine wheel are derived and the relationship between the reliability and failure rate of turbine wheel and life parameter is studied. Then, the method for determining the reliable life parameter of turbine wheel of turbocharger with over-speed failure mode is proposed based on the reliability model and reliability curve. As long as the design parameters including the number of blades, speed, stress, and strength are given, the reliable life of turbine wheel of turbocharger with over-speed failure mode can be determined with the method proposed.
Research of High Speed Train Carbody Structure Vibration Behaviors and Structure Fatigue Strength Characteristic Technology
Authors: Miao Bing Rong , Zhang Wei Hua , Huang G.H. , Wu S.C. , Zhao Yong Xiang
Published: July 2012

The hybrid simulation method based on Multibody Simulation (MBS) and finite element method (FEM) were proposed here and applied to study the relation between carbody structure vibration behaviors and structure fatigue strength characteristic. The detailed steps include: Firstly, rigid-flexible couple vehicle multibody system dynamic model was created and performed to obtain the load time histories corresponded to the typical load cases. Secondly, the carbody structure stresses was calculated through Finite Element (FE) quasi-static stress method. Finally, with the material fatigue property and some uncertainty factors, carbody fatigue damage distribution and life was calculated and evaluated. And the conclusions can be understood that the mechanism between the full vehicle dynamic property and structure damage distribution. The results are also shown that the hybrid simulation technology could be applied into the carbody structure fatigue design.
Aging Properties of the Remaining Components of n-k+1 out of n Systems
Authors: Zhang Zheng Cheng , Liu Hai Zhong
Published: July 2012

This note investigates the residual lives of the remaining components of an (n-k+1) out of n system with independent and identical components after the kth failure has been observed. Some aging properties and stochastic comparisons on the residual life are obtained.
Prediction of Deformations of Steel Plate by GEP in Forming Process
Authors: Yang Lei , Gao Liang
Published: July 2012

Line heating is the main method for forming compound curved shells of hull. The accuracy of final deformation and the productivity depend on the experience of the workers. To predict the plate deformation, the explicit mathematical model for deformation and the main influencing factors by FEA and GEP is established in this paper. The main influencing factors in line heating process were analyzed firstly. Then, 16 group deformation results of steel plate under the five main influencing factors were obtained by FEA. At last, the explicit mathematical model for deformation and the main influencing factors was established.
Fatigue Crack Growth Law Covering Threshold and Fracture Toughness for Railway LZ50 Axle Steel
Authors: Zhao Yong Xiang
Published: July 2012

Long fatigue crack growth rate (FCGR) model covering the range from threshold to fracture toughness is investigated through a series of experiments on the fatigue crack growth behaviour during nearby the threshold district of stage I, steady growth stage II, and the toughness of railway LZ50 axle steel. It reveals that test data in stage II can be reasonably described by employing a statistical distribution for the FCGR data at a given stress intensity factor range level. While the test data nearby the threshold district can be appropriately characterized using a statistical distribution for the factor range data at a given FCGR level and the case is similarly for the test toughness data. Therefore, the model is constructed using the test data in stage II under a control of the statistical parameters of threshold and toughness data on a principle of concurrent probabilities. Availability is indicated by the modeled result for the present material.
Failure Analysis on Bearings of Railway Freight Cars with Radial Bogie
Authors: Zhao Yong Xiang , Zhang B.
Published: July 2012

Causes are investigated on the earlier failures of the bearings for China railway freight cars with radial bogie. Through observing failure objects, checking manufacturing quality, and calculating rolling contact fatigue (RCF) stresses, it reveals that poor manufacturing quality of bearing outer ring plays a key role to the earlier failures and, in addition, mismatch design of RCF stresses between the outer ring and the inner ring acts as an aid actor. Checks verify that surface and core of the outer ring have lower hardness values than requirements; seldom micro-structures, i.e. black-white bands with thickness of around 0.6 to 1.3 mm, appear in the carburized layer of the bearing outer ring; the white part is needle like martensites with higher hardness values, while the black part is pearlites with lower hardness values; and more contingently, crack like manufacturing flaws may appear in the carburized layer with equiaxed grains of ferrites having lower hardness values are around the flaws. RCF values of the outer ring are much larger than that of the inner ring. But the equivalent RCF stress on the present car with radial bogie is lower than that on other cars. This indicates that main cases of the present earlier failures are due the bearings themselves other than the cars.
Failure Analysis on Bearings of Railway Freight Cars with Tilting Bogie
Authors: Zhao Yong Xiang , Zhang B.
Published: July 2012

Causes are investigated on earlier failures of the bearings for China railway freight cars with tilting bogie. Through dissembling failure objects, checking manufacturing qualities and calculating rolling contact fatigue (RCF) stresses, it reveals that RCF plays a key role to the bearing failures. Design mismatch of the RCF stresses between outer and inner rings is main cause of the earlier failures of bearings. It is further verified that the present earlier failures of the bearings on the cars with tilting bogie than others on cars without tilting bogie is a reasonable phenomenon, because the wheelsets on the cars with the tilting are subjected to more severe loads. In addition, material manufacturing flaws, inhomogeneous force transferring circumstances, and seal leak may play an aided role to speed up the bearings failures.
Variable-Fidelity Multidisciplinary Design Optimization Based on Analytical Target Cascading Framework
Authors: Zheng Jun , Qiu Hao Bo , Zhang Xiao Lin
Published: July 2012

ATC provides a systematic approach in solving decomposed large scale systems that has solvable subsystems. However， complex engineering system usually has a high computational cost , which result in limiting real-life applications of ATC based on high-fidelity simulation models. To address these problems, this paper aims to develop an efficient approximation model building techniques under the analytical target cascading (ATC) framework, to reduce computational cost associated with multidisciplinary design optimization problems based on high-fidelity simulations. An approximation model building techniques is proposed: approximations in the subsystem level are based on variable-fidelity modeling (interaction of low- and high-fidelity models). The variable-fidelity modeling consists of computationally efficient simplified models (low-fidelity) and expensive detailed (high-fidelity) models. The effectiveness of the method for modeling under the ATC framework using variable-fidelity models is studied. Overall results show the methods introduced in this paper provide an effective way of improving computational efficiency of the ATC method based on variable-fidelity simulation models.
Small Sample Reliability Analysis of Automatic Ultrasonic Testing of Austenitic Steel Defect
Authors: Zhang Jun , Ding Hui , Li Ming , Ma Guan Bing
Published: July 2012

Reliability analysis of the procedure of ultrasonic technique before inspection has been proved to be essential to ensure the equipment operation safety. The conventional evaluation methods are based on statistical models and a remarkable sample size is needed to get a accurate result. In this work, the Bootstrap model for small sample data is established based on the re-sampling technique. The probability of detection (POD) curves in different conditions are calculated based on the Bootstrap model, and used for quantitative analysis the influence of inspection parameter on stainless steel auto ultrasonic testing result. The calculated result based on bootstrap model is compared with which based on model assisted POD method. The results indicate that Bootstrap model is an efficient tool for the reliability analysis of inspection with small sample data, and insure the inspection result.
Design of Current Selective Protection in Intelligent Molded Case Circuit Breaker
Authors: Zhou Ya Jun , Chen Wen Bo , Chen Zhe
Published: July 2012

Synthetically applied the technology of Full Current Selective Protection and Zone-Selective interlocking mainly, this paper comes up with a new Intelligent Molded Case Circuit Breaker system. Use the accurate calculation method, to achieve a good function of three kinds of current protection. By means of coordinate communication, the system implements selective trip and protection function, and improve the reliability and safety of the distribution system. Self-diagnostic function works when the system goes wrong, which extend the service life of this circuit breaker system.
Testability Design of the PHM System for Aero-Engines
Authors: Wen Zhen Hua , Liu Yuan Peng , Yin Xin
Published: July 2012

PHM (Prognostics and Health Management) for Aero-engines is an effective technical approach to balance the economy and safety of the flight in the total life cycle. In this paper, we mainly analyze the popular issues in the process of designing PHM system for aero-engines including the testability design concept, the scheme of condition monitoring and the utilization extent of condition information. Then presents some useful solutions and advices for the testability design respectively; and analyzes the influence of testability on health management strategies and the main source of uncertainty; then propose a roadmap for making test program based on the PHM requirements and evaluating test program, for improve the utilizing degree of monitoring information, we lastly presented common data fusion methods and some typical examples is illustrated.
Design and Research of Large-Inclination Screw Conveyor Angle Changing Test Equipment
Authors: Zhou Si Zhu , Liu Chun Xue , Jia Hong Yu , Lv Zhi Peng , Sun Zhong Xiao
Published: July 2012

This paper mainly introduces the design of a test equipment for large-inclination screw conveyor, especially focuses on the structure, function and the hydraulic control system. The test equipment can work well under the condition of the variable speed and angle, and even under different structural parameters and different conveyed materials. PLC programmable controller with the hydraulic control system can control the electro-hydraulic proportional valve automatically and eliminate the problems such as dead zone and hysterics of electro-hydraulic proportional valve itself, which helps us to develop a set of the electro-hydraulic control system, and also can be used as a platform for big dip screw conveyor experimental research.
Deposition of Nano Fiber ZnO and Zn1-xCdxO Thin Films by a Simple Spray Pyrolysis and Characterizations for Optoelectronic Applications
Authors: Podder J. , Islam M.R
Published: July 2012

ZnO and Zn1-xCdxO thin films have been deposited onto glass substrate using spray pyrolysis at 200°C. Cadmium-zinc alloy thin films have been prepared by taking different concentrations of cadmium (Cd). The elemental analysis and the surface morphology of the films were carried by the energy dispersive X-ray (EDX) and scanning electron microscopy (SEM). The EDX data show that the films are highly stoichiometric. The SEM images show that the film changes from nano fiber to grain with the increase of Cd concentrations. The X-ray diffraction pattern shows that the films are polycrystalline in nature. The crystal structure of the films changes from hexagonal-ZnO to cubic-CdO depending on the concentration of Zn and Cd in the Zn1-xCdxO films. The optical properties of these films were studied by UV-VIS spectroscopy. The optical band gap of the films was changed from 3.2 to 2.4 with the variation of cadmium.
Development of Gold Nanoparticle Radiotracers for Investigating Multiphase System in Process Industries
Authors: Mohd Yunos Mohd Amirul Syafiq , Hussain Siti Aslina , Abdullah Jaafar , Engku Chik Engku Mohd Fahmi , Othman Noraishah , Radiman Shahidan
Published: July 2012

This paper describes the development of colloidal Au-SiO2 with core-shell structure nanoparticle radioactive tracers by neutron activation in nuclear reactor that produce Au-198 (T1/2=2.7 d) emitting gamma ray of 412 keV. Using conventional citrate-reduction method, gold nanoparticles were prepared from its corresponding metal salts in aqueous solution then coated with uniform shells of amorphous silica via a sol-gel reaction. The citrate-reduction-based method provides gold nanoparticles with higher concentration and narrow size distribution. By using transmission electron microscopy (TEM), the resultant of particle size and silica coatings could be varied from tens to several hundred of nanometers by controlling the catalyzer and precipitation time. Au-SiO2 core-shell nanostructure is good to prevent the particles from getting agglomerated resulting in a big mass. In addition, silica surface offer very good chances that make the hydrophobic and hydrophilic behavior on the gold nanoparticles. EDXRF spectrum has proven that Au-SiO2 core-shell nanoparticles sample consists purely of a gold and silica particles. This target material of radiotracer application used to investigate multiphase system in process industries without disturbing the system operation.
The Effect of Long Term Loading on Epoxy-Based Adhesive Reinforced with Nano-Particles for In Situ Timber Bonding
Authors: Ahmad Zakiah , Ansell Martin P. , Smedley Dave , Md Tahir Paridah
Published: July 2012

The mechanical properties of adhesive materials change over time, especially when they are subjected to long-term loading regimes. The significance of this is often overlooked at the design stage. When adhesives are subjected to a constant load, they may deform continuously, depending on temperature, humidity and cross-link density. This progressive deformation is called creep and will continue until rupture or yielding causes failure. It is imperative that reliable accelerated tests be developed to determine the long-term time-dependent performance of adhesives under different environmental conditions. The long-term creep behaviors of thixotropic and room temperature cure epoxy based adhesives reinforced with nano-particles specially formulated for in-situ bonding of pultruded rod into timber for repair and strengthening of timber structures were investigated. In this study two epoxy-based adhesives with nano-particles (silica fume and rubber) addition were subjected to bending creep tests, in accelerated environments. Experimental data showed that the adhesives reinforced with nano-rubber particles showed less creep deformation than the unreinforced adhesives.
Investigation of Wear Properties of Al-4.5wt.%Cu Nano-Composite Reinforced with Different Weight Percent of TiC Nano Particles Produced by Mechanical Alloying
Authors: Khosroshahi Rasoul Azari , Nemati Narguess , Emamy Masoud , Parvini Naghi , Zolriasatein Ashkan
Published: July 2012

Resistance to wear is an important factor in design and selection of structural components in relative motion against a mating surface. The present work deals with studies on the wear behavior of metal matrix composites manufactured using powder metallurgy technique of ball milled mixing in a high energy attritor and using a blend-press-sinter methodology. Matrix of pre–mechanical alloyed Al-4.5 %wt Cu was used to which different weight percents of nano-sized TiC reinforcement were added. Microstructural characterization of the materials revealed reasonably uniform distribution of TiC reinforcement and presence of minimal porosity. Wear tests were performed using a pin on disk apparatus. The MMCs were rubbed against a carbon steel pin under loads of 10 and 20 N at a sliding velocity of 0.1 ms−1; the environmental humidity lower than 30% and a track length of 1500 m. The degree of improvement in dry sliding wear resistance and hardness brought about by reinforcement is strongly dependent on the weight percent of reinforcement and the wear behavior was determined through the precise measurement of weight loss of the samples. Worn surfaces were analyzed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS).