bluuebunny/crossref_metadata_2025 huggingface dataset:
Principles of Student Assessment in Adult Education
Authors: Martin James B.
Published: September 2010

Any discussion of the topic of assessment of student learning is bound to be marked by strong opinions, marked differences, or total apathy. This topic, critical anywhere in higher education, is even more important in adult learning than anywhere else. With the greater potential for non-traditional programs in adult education, the ability to show the quality of student learning is critical. This chapter examines five principles of assessment of adult learning and provides insight into viable programmatic assessment. By applying the principles, the assessment strategies provided take into account the characteristics of adult learners and design a program that is suited for assessing adult learners. While some application of classroom assessment techniques for adult learners is included, the emphasis of the chapter is on programmatic assessment.
Gaming in Adult Education
Authors: Farmer Lesley S. J.
Published: September 2010

Egames have drawn attention in adult education, particularly as the majority of adults play egames. Adult education is increasingly incorporating serious games, mainly simulation games, but other forms such as RPGs are being considered. In addition, adult education is also incorporating game design into curricula. In terms of learning theory, gaming as a learning mechanism is usually associated with activity theory. Many commercial off-the-shelf (COTS) game combine solid content and concept along with good game play that engages adult learners. The gaming industry has increased focus on developing games for mobile instruments, mainly smart phones. Specific applications of egames for engineering education are discussed. Recreational aspects of gaming impact educational us of egames. Future trends of adult education use of egames are noted: platform, workplace gaming, and industry development.
Traditional Instructional Design for Online Learning vs. Unconventional Instructional Design
Authors: Brewer Ernest W. , Stockton Stephen D.
Published: September 2010

In the field of online learning, instructors need to move past the limitations that are imposed by a traditional instructional design mindset and embrace new ways of approaching instruction. Online learning can remove barriers of space and time and provide a learning experience that is focused on the learner. Educators need to understand the way technology is reinventing communication and enhancing how information is processed. Only by accepting the unconventional instructional designs that technology can bring, can educators be prepared to reach and teach the students of this digital age.
Blackboard Learning System on College Campuses
Authors: Santhiveeran Janaki
Published: September 2010

This chapter presents a synopsis of the Blackboard Learning System (BLS), highlights how the BLS has been used in college campuses, and describes the uses of Blackboard tools based on author’s experience in California State University, Long Beach for graduate level courses. Also, this chapter reflects on the author’s experiences in developing and facilitating online classroom groups by using Blackboard tools. Topics discussed include the use of electronic bulletin board and virtual chat in creating online classroom groups. Group dynamics and procedures such as group formation, membership, cohesion, the roles of facilitators, and interaction patterns are summarized. The classroom group interaction pattern is discussed using sample online postings. The author describes how Teaching and Learning Cycle (TLC) framework is enhanced with the integration of the Blackboard tools for course management, interaction, and assessment of student progress in learning. Finally, this chapter concludes with advantages, recommendations, and future trends.
Online Learning and Instruction in Health
Authors: D’Abundo Michelle Lee , Sidman Cara Lynn
Published: September 2010

Online learning and instruction are important components of adult education in the field of health. This chapter describes how computer-based technologies are being applied in the training and continuing education of health professionals and in health promotion. Curriculums previously thought to be inappropriate for web-based delivery are now being offered online. Innovations in online learning and instruction have improved delivery of web-based education and have provided educational opportunities for many that were “unreachable” by traditional classrooms. An example of how a solely face-to-face course was revised and delivered in three formats including face-to-face, blended and completely online is provided, as well as examples of best practices and future trends for online learning and instruction.
Staying Legal and Ethical in Global E-Learning Course and Training Developments
Authors: Hai-Jew Shalin
Published: September 2010

In global e-learning, a mix of laws, policies, and professional practices informs the work environment. While legal issues may be addressed at the institutional level through the important work of legal counsel (university lawyers) and administrators, line-level faculty and staff have responsibilities to uphold and adhere to a variety of laws, ethical principles, policies, and “best practices” for staying legal.
Increasing Adult Learner Engagement in E-learning Courses through Learner Case Writing
Authors: Closson Rosemary B. , Stokes Carmeda
Published: September 2010

This chapter proposes learner case writing (LCW) as a case-based method that has been successfully used to increase adult learner engagement in an online asynchronous environment. LCW is a response to the expressed need identified in the literature for increased incorporation of experiential activities in e-learning environments. A critical discussion of the theoretical base and learning principles that underpin this method (such as experiential learning, action learning, authentic learning, and situated learning) is also provided. Phases of the LCW process are outlined and key challenges the authors encountered while using the LCW process online are presented. The authors describe their responses to mitigate the challenges experienced and make general recommendations for online learning using experiential approaches. This chapter concludes with final thoughts on future trends.
Bringing Together Personal Learning, Higher Education Institutional Elements, and Global Support for a Re-Orientation toward a Focus on Lifelong Learning and Education
Authors: Henschke John A.
Published: September 2010

This extended research study focused on bringing together personal learning, higher educational institutional elements to be considered for helping higher educational institutions and individual learners in various countries to re-orient themselves toward a focus on lifelong learning, and placing this within the support and context of lifelong learning and education around the globe. Research is presented on the background and experiences of various higher educational institutions and individual learners in this regard, developing a tentative policy statement and identification of the elements of a re-orientation toward lifelong learning focus as products of several worldwide conferences. In addition, the support of UNESCO in its global reach encourages this to move forward rapidly into the future.
Barriers to Adult Education Participation, Distance Education, and Adult Learning
Authors: Isaac E. Paulette
Published: September 2010

Volumes of research exist which explains adults’ participation in adult education. Research suggests that adults participate in adult education for a variety of reasons. Nonetheless, adults also face a variety of barriers to their participation. Whether in a traditional or distance education format, adults may confront barriers to their learning. Now that technology plays such an important role in adult learning, new and returning adults may find additional barriers. Some barriers are within learners’ control. On the other hand, institutions can take measures to eliminate other barriers and enhance learning.
Using Principles of Andragogy to Teach Writing to Graduate Students Online
Authors: Kania-Gosche Beth
Published: September 2010

While online courses may be more convenient and fulfilling for adult learners, they pose an additional challenge because much of the communication between student and instructor is in writing. This is in addition to more formal, traditional written assignments like research papers. The challenge multiplies with graduate students, who may be years or even decades distant from their undergraduate writing courses, while the expectations for their writing are higher. Many graduate programs culminate with a final project, thesis, or dissertation, which often involves extensive research and writing. Many similarities exist between the literature on teaching writing and teaching adult learners; however, teaching writing within the contest of an online graduate course is an area of research that still needs to be expanded.
Load Distribution over Raceways of an 8-Point-Contact Slewing Bearing
Authors: Gao Xue Hai , Huang Xiao Diao , Wang Hua , Chen Jie
Published: September 2010

An 8-point-contact slewing bearing is usually applied with strict requirements. The load distribution over raceways is the fundament to calculate both the static and dynamic capability of a slewing bearing. The paper discussed a method for calculating the load distribution in an 8-point-contact slewing bearing under general load conditions (turnover moment, axial load and radial load). Based on the method, some suggestions were proposed for optimization of the slewing bearing design.
Search Technology of Resource Service in Manufacturing Grid Based on Ant Colony Optimization Algorithm
Authors: Lou Jing , Xu Hong Xiang
Published: September 2010

In Manufacturing Grid (MG) system, there are primarily two kinds of users: resource service consumer and resource service provider. For a resource service request task, the MG system should search the services which are qualified for the requirements of consumer and then choose the optimal one to execute it. In according to the distributed system structure of MG and node routing model influenced by several factors (e.g., time minimization, cost minimization, bandwidth minimization), the searching technology based on web service technology and ant colony optimization (ACO) algorithm has been proposed in this paper. The basic evaluation models and formulations are described, and then the algorithms are presented to minimize the expenses. The experimental results also show that the proposed method is useful in solving the searching problems in MG system.
Experimental Study of Fracture Controlled Blasting
Authors: Zhu Zhi Wu , Li Yi
Published: September 2010

A new method of fracture controlled blasting was put forward—using different coupling medium (water and gas) within the hole at the same time. The paper studies the pressure of hole wall about the hydraulic pressure blasting and gas decoupling blasting by system experiment, and compares the strain with damage on different medium directions after blasting, which reflected the suffering force and distortion of medium. The blasting method can control the process of energy releasing and direction effectively, which makes it possible to destroy one side of the wall rock and protect the other side at the same time.
New Computational Method for a Class of Optimization Problems in Production System and System Engineering
Authors: Feng Qi Gao , Mao Han Ping , Wei Yan Fang , Jiao Hong Wei
Published: September 2010

In this paper, a new computational method is proposed for solving a class of optimization problems which have broad applications in production system and system engineering. Firstly, by exploiting structure of the problem, linear relaxation programming of the original problem is constructed. By using simplex method we can solve a sequence of linear relaxation programming, the proposed algorithm is convergent to the global minimum of original problem through the successive refinement of the feasible region of a series of linear programming problems. In finally, numerical experiments are given to show the feasible of the proposed method.
Fuzzy Evaluation of Maintainability with Tribological Factors at Design Stage
Authors: Li Jing Rong , Wang Qing Hui , Shen Hong Zhou
Published: September 2010

Excellent maintainability is extremely important not only supplementing reliability necessarily but reducing product life cycle cost and enhancing its quality greatly. Industrial experiences have shown that wear and friction related failures of tribological components, are one of the main reasons for maintenance. However, most of the research works evaluated tribo-maintainability at maintenance stages. This paper analyzed the tribo-maintainability related design factors from systematic perspective and concluded a more complete set of six factors. A fuzzy set based approach is then developed to quantitatively evaluate design for its tribo-maintainability. A case study with a common assembly of a gear reducer has demonstrated the effectiveness of the prototype developed.
A New Verification Method of Digital Circuits Based on Cone-Oriented Partitioning and Decision Diagrams
Authors: Pan Zhong Liang , Chen Ling
Published: September 2010

The formal verification is able to check whether the implementation of a circuit design is functionally equivalent to an earlier version described at the same level of abstraction, it can show the correctness of a circuit design. A new circuit verification method based on cone-oriented circuit partitioning and decision diagrams is presented in this paper. First of all, the structure level of every signal line in a circuit is computed. Secondly, the circuit is partitioned into a lot of cone structures. The multiple-valued decision diagram corresponding to every cone structure is generated. The verification procedure is to compare the equivalence of the multiple-valued decision diagrams of two types of cone structures. Experimental results on a lot of benchmark circuits show the method presented in this paper can effectively perform the equivalence checking of circuits.
A Modeling and Representation Method for Virtual Assembly System
Authors: Chen Cheng Jun , Wu Yun Feng , Yang Yong
Published: September 2010

To transform CAD model into virtual assembly model, model transformation was divided into two processes, namely part model transformation and assembly constraint model transformation. With secondary development of SolidWorks system, both part model and assembly constraint model were extracted form SolidWorks model. The OpenFlight database, which is a standard format for virtual reality simulation, was used to represent the hierarchical model of part. Assembly constraint model was expressed by object-oriented hierarchical model in text file. These two models were associated with each other using unique name or number. By loading part files and assembly constraint file, the assembly model was reconstructed in virtual assembly system. The experiment verified that the presented method was effective.
Numerical Analysis on Thermal and Stress Coupling of Soil Subgrade
Authors: Zhu Zhi Wu , Ning Jian Guo
Published: September 2010

This paper focuses on the situation of stress, strain and displacement of subgrade under the action of temperature and load. Carry out numerical simulation for strain problem of normal subgrade plane and compare the numerical results of stress field and displacement field to the analysis results obtained from predecessor, we can find that the distribution of every value is in conformity to its variation trend. The variation of stress and displacement shall be most violent at the top surface of subgrade, thus the effect of temperature and load on stress and displacement will decrease as the depth increases. Moreover, the capacity of calculation and visualization for program is developed greatly, which can supply beneficial assistance to engineering design and appliance.
Grid Resource Discovery Strategies Base on Multi-Economic Agent
Authors: Xie Jun , Li Ji Guang
Published: September 2010

The paper presents a market oriented resource allocation strategy for grid resource. The proposed model uses the utility functions for calculating the utility of a resource allocation. This paper is target to solve above issues by using utility-based optimization scheme. We firstly point out the factors that influence the resources’ prices; then make out the trading flow for resource consumer agents and provider agents. By doing these, the two trading agents can decide their price due to the dynamic changes of the Grid environment without any manmade interferences. Total user benefit of the computational grid is maximized when the equilibrium prices are obtained through the consumer’s market optimization and provider’s market optimization. The economic model is the basis of an iterative algorithm that, given a finite set of requests, is used to perform optimal resource allocation.
A Comprehensive Evaluation Model of the Solution to the North Pacific Ocean Garbage Patch
Authors: Chang Cheng , Zhang Yuan Biao , Wei Shi Wei
Published: September 2010

This paper analyzes the formation of the Great Pacific Ocean Garbage Patch and its negative influences. Then, for evaluating the effectiveness and feasibility of these methods, we conduct cost-effect analysis on the economic costs and benefits; and undertake an analysis on the effects of the solutions concerning social benefits; then, establish a comprehensive evaluation model of solutions after combining the economic and social factors, which eventually gives birth to workable policy recommendations.
Application of Digital Image Monitoring System in Strain Measurement of Cantilever Steel Beam
Authors: Li Peng Hui , Wen Yin Ping , Zhao Wen Guang , Zhu Hong Ping
Published: September 2010

The realization of strain measurement based on digital image processing technique is discussed. Combined with the strain measurement principle and the optical imaging feature, considered the axisymmetrical and non-axisymmetrical distortion, the automatic surface-fitting calibration method based on region growing is adopted. Cubic polynomial is applied to establish the relationship between the object space and pixel coordinate system. The expectations based on wavelet coefficients are used for sub-pixel edge detection, measurement accuracy can reach 0.02 pixels. Accuracy of displacement for strain measurement achieves micrometer-level. The theoretic validity and practical feasibility of the system are proved by the strain measurement of a cantilever steel beam.
Study on Divergence Based on the Grey Relational Degree in the Group Decision-Making
Authors: Wang Jun Ying , Li De Hua , Wu Shi Hong
Published: September 2010

Expert is a very important factor that affects the outcome of decision-making. This paper applies the grey relational degree in measuring the similarity on the evaluation of decision-making scheme between individual expert and expert group, and establishes the research model of expert's decision-making divergence, which provides some theoretical basis for expert’s evaluative reliability and fairness, reveals some possible bias in attribute understanding as well as important deficiencies or loopholes that existed in schemes. Besides, it provides a better way of man-machine interface for hall for workingshop of metasynthetic (HWME) and a good chance for further discussion about minority’s different opinions. Finally, the approach is proved to be effective in revealing the divergence and deviation of decision making through the example.
Design of Variable Structure Control with Bounded Inputs
Authors: Zhou Qing Kun , Bai Sheng Jian , Zhang Zhi Yong
Published: September 2010

The design of variable structure system inputs which are constrained by saturation is studied. For a LTI system which satisfies some conditions, it is shown that appropriate bounded controllers guarantee the system’s global stability and maximize the sliding mode domain on the switching surfaces. Stability conditions of variable structure systems with constrained inputs are relaxed, and the stability of the closed-loop system is guaranteed by using passivity theory of linear passive systems. Moreover, nonlinear sliding surfaces are discussed for variable structure controller design, and a novel nonlinear switching surface is proposed. Finally, the proposed methods are applied to a 2nd order LTI system to show their usefulness.
Matching Relationship between Frequency Characteristic and Parasitic Error of Compliant Linear Buffer Mechanism
Authors: Zhou Qing Kun , Lu Ya Fei , Fan Da Peng , Zhang Zhi Yong , Zhang Lian Chao
Published: September 2010

A novel compliant linear buffer mechanism (CLBM) is designed for impact isolation. In view of the incompatible relationship between frequency characteristic and parasitic error of compliant linear mechanism, the mixed compliant linear mechanism(MCLM) is proposed by combining the Lumped Compliant Mechanism(LCM) and the Distributed Compliant Mechanism(DCM).The topology matrices for four kinds of parallelogram linear compliant mechanisms are built through the method of type synthesis. The characteristic polynominal (CP) for the compliant mechanism matrices[CM] are calculated for the isomorphism detection of compliant mechanism. The finite element analysis (FEA) model of these four kinds of linear compliant mechanism is built to complete numerical analysis on the structure frequency and parasitic error with different sizes, and the relationship between the frequency characteristic and parasitic error of the compliant linear mechanism is found out. MatlabTM software is used to obtain the functional formulas by the method of polynomial curve fitting (PCF) for The FEA results show that the structure configuration of MCLM can achieve a higher structure frequency and a greater kinetic precision over the pure LCM and DCM at the same time, and also indicates that the analysis method of frequency characteristic and parasitic error for compliant mechanism is efficient and should be effective on the structure optimization of the novel CLBM.
Application of Performance Baseline in Network Measurement
Authors: Jiang Xi Jiong , Feng Hong Qi
Published: September 2010

This document analyzes characteristics of IP network measurement and common network performance indicators, and proposes the measurement guide of baseline theory aiming at traditional network measurement that focuses on measurement result and neglects process management and control. The article normalizes network performance baseline measurement, describes network performance baseline setting, designs baseline measurement management model, and optimizes and improves network performance measurement program by taking throughput baseline measurement in production network performance measurement as example.
Rotational Speed and Noise Level due to Distribution Oil Window Size of Three Type Pumps
Authors: Wen De Sheng , Wang Zhi Li , Lv Shi Jun , Sun Jiang Bo , Du Li Bin
Published: September 2010

In this paper, a new hydraulic pump was presented, called KZB pump which has obtained the national patent of invention (patent number: 85103289.3). Originally comes from CY series pumps that are common used at present, KZB pump shows many advantages, such as high pressure, high efficiency, and long service life etc. This paper focuses on the rotational speed and noise level analysis of this new pump. Firstly, we described the configuration of both semi-open and full-open axial piston pumps in detail, which both of them were all new pumps and the later was also called KZB pump. Next, we investigated the distribution oil window size that influences the pump's rotational speed and noise level mostly by mathematical analysis. Finally, the analysis and comparisons of the rotational speed and noise level performances for the three type pumps which mentioned above were made. It is proved through the test that under the same working conditions KZB pump has made great advanced in controlling noise and having lower self-absorption rotational speed compared with the other type pumps.
Reliability-Based Design Optimization of Valve-Spring Using Evidence Theory and Genetic Algorithm
Authors: Guo Hin Xin , Dai Juan , Hu Guan Yu , Cheng Li Zhi
Published: September 2010

The design optimization of valve-spring is achieved under the condition of expected reliability. The restrain conditions about the reliability of static strength and fatigue strength are considered, and then a dual-objective optimal problem of valve spring is modeled to obtain the lightest mass of valve-spring and the minimum error of spring stiffness. The feasibility of reliability condition is discussed based on evidence theory in order to improve the computational efficiency. By means of the combination of evidence, the upper and lower bounds of reliability are obtained, and a substituting model of restrain condition about reliability is proposed based on the obtained bounds of reliability. After the weighted combination of two objective functions is made, the optimization model is solved by using genetic algorithm. An example is given and it shows that the proposed method is effective.
Curvature Estimation to Scattered Point Cloud
Authors: Cheng Shao Hua , Zhou Yong Wei , Shi Jin Fa , Zhang Li Tao
Published: September 2010

A new local fitting algorithm of implicit quadric surface is presented for space scattered point cloud. For the fitting objective function, the algorithm obtains ten groups coefficients of implicit quadric surface with ten different constrains and gets the final coefficients by taking arithmetic average of ten groups coefficients. Based on the curvature formula of implicit quadric surface, the point cloud data curvature can be calculated. The numerical example demonstrated the efficiency of curvature estimation algorithm.
Nonlinear Vibration Characteristics of Helical Spring
Authors: Wang Nan Nan , Hou You Fu , Tian Zu Zhi
Published: September 2010

A helical spring has large deformation under the condition of near resonance, in order to obtain the nonlinear vibration characteristics, the single-integral constitutive relations of helical spring based on nonlinear theory are discussed firstly, then nonlinear dynamic characteristics of helical spring are analyzed based on finite element technology. Finally, the dynamic simulation associated with flexible characteristics for helical spring is studied in ADAMS. The results show that the maximum stress of helical spring appears at transition region between different radius which is consistent with fracture position actually. Flexible dynamic response of helical spring mainly behaves low frequency vibration which is different from rigid body dynamics response.
Mechanical Determination of Re-Fracture Well Create New Fracture
Authors: Zhao Wan Chun , Wang Ting Ting , Ju Guo Shuai
Published: September 2010

The mechanical distribution of refracturing rock around well is Considered, the induced stress of vertical fractured well changes in pore pressure is first to establish, taking into account the fluid compressibility, the introduction of the initial artificial fracture fluid factor, an evolution model of in-situ stress is built up for initial fracture. Consider the impact of temperature on the reservoir rock, an evolution model of the temperature induced stress model is built up, Combined with in-situ stress field, an evolution model of Mechanical determination conditions of re-fracture well create new fracture is built up. Calculation of a block of Jilin Oilfield injection wells by the three effects of stress around an oil well, the theoretical calculation results are consistent with the field.
Research on the Efficiency of Metal Belt Continuously Variable Transmission for Vehicle
Authors: Jiang Qiang , Liu Hong Yi , Hao Jian Jun
Published: September 2010

The efficiency of continuously variable transmission for vehicle is an important factor impacting on its performance, many kinds of power loss in process of shifting down and up are analyzed by means of theoretical and experimental ways, it can be seen that the power loss between metal-belt and pulley, which includes three items of loss: the entering and out of pulley; the slip between elements and surface of pulley; the slip of between steel bands and elements, is a major one. The calculating formulas are founded. The comparison of calculating results with experimental results under the different ratio, it is good coherence between them which has a guiding function for the design of TCU.
Two Mechods to Get Lateral Pressure of Bulk Material on Squat Silo
Authors: Shao Xing , Zhang Wei Xiang
Published: September 2010

The two limit equilibrium methods of bulk material (Variation method and wedge model method) is employed to analyze models of sliding cuneiform volume of bulk solid, the lateral pressure formula for squat silos and equations of failure plane about sliding cuneiform volume are obtained. Variations of the positions of failure plane with height/diameter ratio are analized on the basis of the analysis for positions of failure plane by solution of these equation. The applied range and calculation method of the formula, and pressure distribution are discussed. The effects of friction between bulk solid and squat silos on the positions of failure plane and lateral pressure of bulk solid are discussed. The conclusion is that caculation results is available for squat silo design when the friction takes no into account, and the applied range of the formula is that height/diameter ratio equals 1.3. It is widely appicable for almost all squat silos. The caculation results agree with that of the full-sized silo experiment. This is a reasonable calculation method for design of squat silo.
Simulations on Sliding Process between Si-DLC and DLC Films on a Water-Lubricated Condition
Authors: Lan Hui Qing , Liu Can , Kato Takahisa
Published: September 2010

Diamond like carbon (DLC) films have been extensively studied over the past decades due to their unique combination of properties, in particular, silicon-doped DLC (Si-DLC) films are of significant interest for tribological effects, they had a very low friction coefficient and possess the potential to improve wear performance in humid atmospheres and at higher temperature. But many experimental results of the Si-DLC films showed that their tribological properties changed greatly on different silicon contents. In the paper, molecular dynamics (MD) simulations were used to study a sliding friction process between Si-DLC and DLC films on an un-lubricated and a water-lubricated condition respectively. The results have been shown that a transfer film between the Si-DLC and DLC films was formed on the un-lubricated condition. In contrast, a boundary lubrication layer was found on the water-lubricated condition. Moreover, the friction force on the un-lubricated condition was larger than those on the water-lubricated condition.
Study on the Calculation Method of Gas Flow in Vacuum System Based on the Fluent Software
Authors: Zhang Shi Wei , Liu Jin Ce , Song Guang Zhe , Zhang Zhi Jun
Published: September 2010

In order to improve the calculation method of the vacuum system design, the research focus on the way applying the Fluent software to calculation of gas flow in vacuum system in this paper. It is proved that the permission pressure lower limit is 1Pa for meeting the continuity hypothesis. The applicable flow patterns include turbulent flow, laminar flow and transitional flow between turbulent and laminar flow, which are totally defined as the viscous flow in the traditional vacuum field. By means of user define function (UDF), a layer mesh cell of negative quality source is defined to simulate the constant volume flow rate at the inlet of positive displacement vacuum pump, which makes up for the lack of compressible fluid velocity outlet boundary conditions in Fluent. The usability of Fluent in vacuum system is confirmed by a successful calculating example of gas flow in an ice condenser of vacuum freeze dryer.
On the Numerical Study of Bubbly Flow Created by Ventilated Cavity
Authors: Xiang Min , Cheung S.C.P. , Tu Ji Yuan , Zhang Wei Hua , Fei Yang
Published: September 2010

The aim of the study was to develop a numerical model to reproduce the bubbly flow field created by ventilated cavity which includes three different regions. The model was established based on the Eulerian-Eulerian two-fluid model coupled with a population balance approach which is solved by the Homogeneous Multiple-Size-Group (MUSIG) model to predict bubble size distribution. Base on the model, the simulation was carried out at the experimental condition of Su et al. (1995). Firstly three regions were successfully captured proved by the spatial voidage distribution and streamline shape. Then distributions of void fraction and Sauter mean bubble diameter at various sections below the cavity corresponding to three regions respectively were plotted against experimental data. A close agreement was observed in the void fraction distribution which indicates that qualitative details of the structure of the two-phase flow field below the cavity was successfully produced. The Sauter mean bubble diameter in the pipe flow region was under-predicted for about 10%. In conclusion, the proposed model was validated in predicting the multi-region flow field below the ventilated cavity which will provide a valuable insight in designing and controlling of the two phase systems with the detailed flow field information obtained.
Vibration Analysis for Elastic Vascular Stent
Authors: Ma Sheng Mei , Shang Xin Chun
Published: September 2010

A mathematical modeling for breathing vibration problem of vascular stent is presented. The vascular stent is considered in structure as an elastic cylindrical lattice shell, in which the cell element is treated as a spatial frame structure. Based on the force equilibrium and the deformation geometry analysis for the cell element, calculative formulae for effective elastic parameters of the lattice shell are obtained by using homogenization method. Hence, the vascular stent is modeled as an orthogonally anisotropic thin shell. The equation of vibration for vascular stent is derived from Flügge shell theory. The computation of natural frequency of vibration is performed. The analytic results from the presented formulae are close to that from finite element method by the means of ANSYS, which validates the applicability of the presented modeling of vascular stent structures. The vibration analysis could be a useful reference for practical engineering designs of vascular stent.
The Research of the Active Cells Balancing by the Inductive Charge Transfer
Authors: Xu Xin Min , Wei Xue Zhe
Published: September 2010

With the development of the electric vehicles, serial connected cells have a broad prospect in the future. But the difference of the serial connected cells especially for Li-ion cells is prone to cause a lot of problems, such as overcharge and overdischarge. For these reasons, various cells balancing methods are applied. In this article main balancing methods will be compared, and as a result, the inductive charge transfer method will be adopted to balance the cells due to its obvious advantages. Furthermore, the principle and the realization of this balancing system will also be explained.
Stability Analysis of Non-Viscous Granular Media Seepage Failure Based on Particle Method
Authors: Zeng Zeng , Dang Fa Ning , Zhang Ze Hui , Wang Qiu Jie
Published: September 2010

This paper reviews the development and discusses the fundamental theory of particle method. According to different Cu value’s grain size curves, three numerical models have been settled by using implicit solver embedded software-PFC which is based on DEM for fluid-structure interaction calculation. In order to get the criteria of seepage failure in granule system, the real-time force chain and flow vector under different hydraulic gradient have been recorded. Process shows that particles move when hydraulic gradient rises but the granule system’s failure would not happen unless an enough high hydraulic gradient value is reached. The result points out that difference between unstable granule system under seepage and the stable granule system under seepage, whose force-chain and flow vector is stable and process convergence can also be got after several time-steps calculation is made, can be the proof whether the granule system fails or not.
The Analysis of Thrust Fault in the Tensional Environment
Authors: Hao Hui , Qi Jia Fu , Cheng Jian Li
Published: September 2010

Gravity glide thrust fault is always a significant type of thrust fault in the extensional basin. The research on it is of great significance for its playing an important role in hydrocarbon migration and accumulation, being one of the major targets of oil and gas exploration. Through finely analyzing Paleogene structure of Wangguantun region in Huanghua sag, specially re-analyzing the particular fault, utilizing kinematic equilibrium rule and analyzing the thrust fault developing process, I found there were discrepancies in predecessors′ interpretation to the thrust fault in the area: this fault did not form during the late period. It formed from a slump fault with small growth rate whose fault section dip changed mild, even level because of depocenter migration. The fault was pushed by the force of gravity so that the hanging wall slid along the fault plane, and makes the scan finally in the late revealed the nature of a thrust fault. Although the shape of these faults is very similar with the thrust fault formed late in previous view (early growth coefficient is small, displacement had little change), there are huge differences on origin of these two faults whose petroleum geological significance is quite different. This study is very significant to the structure research of the region and the other similar regions, providing the new theory for oil exploration.
On the Transversal Vibration of Pile-Yarn with Time-Dependent Tension in Tufting Process
Authors: Gao Xiao Ping , Sun Yi Ze , Meng Zhuo , Sun Zhi Jun
Published: September 2010

In this paper, the non-linear tranverse vibration of an axially moving pile-yarn with time-dependent tension are investigated. The pile-yarn material is modeled as Kelvin-Voigt element. A partial-differential equation governing the transverse vibration is derived from the Newton’s second law. The Galerkin method and the fourth order Runge-Kutta method are used to solve the governing non-linear differential equation. The effects of the transport speed, the tension perturbation amplitude and the damping coefficient on the dynamic behaviour of the system are numerically investigated.
Transformer Fault Diagnosis Based on Improved Quantum Genetic Algorithm and BP Network
Authors: Wei Jie , Yu Hong , Li Jin
Published: September 2010

Three-ratio of the IEC is a convenient and effective approach for transformer fault diagnosis in the dissolved gas analysis (DGA). Fuzzy theory is used to preprocess the three-ratio for its boundary that is too absolute. As the same time, an improved quantum genetic algorithm IQGA (QGASAC) is used to optimize the weight and threshold of the back propagation (BP). The local and global searching ability of the QGASAC approach is utilized to find the BP optimization solution. It can overcome the slower convergence velocity and hardly getting the optimization of the BP neural network. So, aiming at the shortcoming of BP neural network and three-ratio, blurring the boundary of the gas ratio and the QGASAC algorithm is introduced to optimize the BP network. Then the QGASAC-IECBP method is proposed in this paper. Experimental results indicate that the proposed algorithm in this paper that both convergence velocity and veracity are all improved to some extent. And in this paper, the proposed algorithm is robust and practical.
Model-Free Algorithm for Friction Torque Adaptive Identification and Compensation
Authors: Zheng Li Jun , Cheng Xin Mei , Chen Shan Shan
Published: September 2010

In order to solve the electro-hydraulic system position tracking control problem, which caused by the nonlinear system friction torque disturbance, a model-free algorithm for the friction torque adaptive identification and compensation was put forward. The algorithm is based on the application mathematics knowledge and matching & following principle. It can accommodate to all situations with the friction torque (force) variety. The simulation result indicates that the algorithm can restrains the interference of the friction torque (force) effectively, and the system’s low speed character and tracking performance were been improved.
Study on Road Simulation Test of Motorcycle
Authors: Shi Xiao Hui , Zou Xi Hong , Yang Ping
Published: September 2010

The principle of remote parameter control(RPC) and test method of road simulator test are analyzed, and the road simulation test of motorcycle is implemented with road simulator produced by MTS company. Firstly, by disposing strain gauge and accelerometer, the load spectrum of motorcycle is sampled when the motorcycle runs on gravel road and concrete road with constant speed. Then using the front and rear axle acceleration as desired response signals, the simulation iteration and road simulation test are conducted. At last, the key problems of motorcycle road simulation test are solved. The result shows that the desired response signals and the monitor signals are well matched, and the road load spectrum of motorcyle is accurately reproduced.
The Casting Process Design and Simulation of the Volute of 65ZGB Slurry Pump
Authors: Zhi Xiao Hui , Han Yan Jun , Wang Hai Hua
Published: September 2010

The casting process design and simulation of the volute of 65ZGB slurry pump were presented in this paper. The casting process design principle, process parameters, points of attention, and the simulation parameters were introduced. Huazhu CAE was used to simulate the casting process. The STL document used in Huazhu CAE was converted from the 3D moulding of the casting process using the Solidwork software. The simulation results and practical production showed that the casting process can reduce shrinkage defects of the casting.
Gear Crack Assessment Using Correlation Dimension
Authors: Feng Zhi Peng , Zuo Ming J. , Chu Fu Lei , Xiao Cheng Yong
Published: September 2010

Fractal dimension reflects the complexity of dynamic systems, and contains the health status information of machinery. The experimental vibration signals of a gearbox with different gear crack size are analyzed using correlation dimension, and it is found that the correlation dimension increases monotonically with the increasing crack level. This is consistent with the nature of a nonlinear dynamic system: the more severe the fault, the more complicated the dynamic system, and accordingly the larger the fractal dimension. Correlation dimension has potential to assess gear localized damage.
Fractal Applications in Fluid Mechanics of Enhancing Oil Recovery from Low-Permeability Oil Reservoirs by Gemini Surfactant Flooding
Authors: Wei Heng , Wei Lei , Yin Jian Hui , Yin Fu Ling , Liu Jun Han , Li Hou Hua , Wei Guo Qi , Liu Xian Gui , Liu Wei Dong
Published: September 2010

Gemini surfactant flooding is a promising technique to enhance oil recovery from medium-high permeability oil reservoirs. The screening of the surfactants is mainly based on their capability of lowering the surface tension between oil and water. However, gemini surfactants with high capability of lowering the surface tension do not necessarily enhance oil recovery from low-permeability oil reservoirs. Based on the fractal analyses of low-permeability cores and molecular spacer group, the fluid mechanics of gemini surfactant flooding in low-permeability oil reservoir is discovered. The fractal dimensions of the spacer group of gemini surfactants should match the fractal dimensions of the pore structures of low-permeability oil reservoirs.
Design of Mounting Bracket for Missile-Borne Laser Gyroscope INS
Authors: Wu Bin , Wang Hai Feng , Huang De Dong , Ding Pi Man
Published: September 2010

Since the circle error probability (CEP) of the laser gyroscope inertial navigation system (INS) based on a certain weapon control system is a little larger in ground dynamic navigation test, an effective vibration-damping system has been designed. Data processing for the vibration experiments’ results and normal mode analysis show that the resonance frequency of the original mounting board is near the mechanical dither frequency of the laser gyroscope, which can lead to a larger mounting board response at the mechanical dither frequency. This is the main reason for the larger navigation error. A stiffer mounting board was designed, and another mounting bracket with better dynamic characteristics was developed. Ground vibration experiments and navigation simulation for laser gyroscope show that the new vibration isolation system can feed the desired requirements.
Research on Flow Characteristics of Slide Valve Used in Water Hydraulic Servo Valve
Authors: Wang Xin Hua , Li Wei , Sun Shu Wen
Published: September 2010

Water hydraulic servo valve has become an important research subject nowadays, and its secondary amplifier usually uses slide valve. Research on flow characteristics of water hydraulic slide valve is important to the design of water hydraulic servo valve. Based on the classical theory of incompressible flow, CFD software FLUENT is used to simulate and analyze the flow characteristics of water hydraulic slide valve. Simulations with different boundary values are applied to the same slide valve in order to guarantee the accuracy of the simulation results. Detailed comparisons are made between throttles with different structure parameters, including spool diameter, spool opening, flow passage diameter and equalizing slots so as to define the parameters respectively. The results indicate that the flow rate of the slide valve designed is approximately proportional to the spool opening within certain travel. Finally, the structure parameters of the slide valve that satisfy the design requirements are obtained. The simulation results provide theoretical basis for the design and improvement of water hydraulic slide valve used in water hydraulic servo valve.
Experimental Study on Convolution Flow near Charged Spray Nozzle
Authors: Wang Zhen Tao , Wang Jun Feng , Jia Wei Dong , Luo Ti Qian
Published: September 2010

The electrostatic jet flow has been widely employed to crop-dusting, painting, fuel spray and combustion, electrostatic painting, dust particles and flue gas removal. In order to investigate the convolution flow structure near the nozzle, discuss the effects of electrostatic voltages on convolution flow form, development and the aggrandizement of droplets mass transfer. PIV (Particle Image Velocimetry) was employed to measure and analyze the convolution flow near the nozzle under different voltages, and the velocity vectors and streamlines were gained. Experiment and analysis indicate that convolution flow structure has been existed in electrostatic jet flow brim and the main jet flow section change is inconspicuous with voltages adding; Electrical filed intensity has been enhanced and the droplets convolution flow was picked up with the electrostatic voltages adding. The convolution flow structure could quicken the gas mix into the main jet flow, and enhanced the droplets absorbency.
Dynamic Analysis of Multistage Gear Driven System of Wind Turbine
Authors: Liu Yong Qian , Long Quan , Yang Yong Ping
Published: September 2010

At present, wind power is developing rapidly. Gearbox is one of the key components of wind turbine. The equivalent dynamic model of the wind turbine gear driven system was established with lumped-parameter method, and the differential equations of torsional vibration were set up based on Newton Second Principle; the natural frequency and main vibration mode of the gear driven system were calculated and the characteristics of the vibration shapes were analyzed. The results have established basic for dynamic response calculation and analysis of the gear driven system, and provides a reference for system optimization design.