bluuebunny/crossref_metadata_2025 huggingface dataset:
Problems and Suggestions for Farmers Adoption of IPM Practices in Rice (Oryza sativa L) Cultivation
Authors: Rahman MM
Published: July 2012

A study was carried out to determine the problems in IPM practices for rice  cultivation faced by the farmers trained in IPM through Farmers Field School (FFS) and also to find out the important probable suggestions for overcoming those problems. Data were collected from 158 respondent farmers sampled randomly from 1050 FFS farmers of Godagari Upazila in Rajshahi district. Twenty important problems regarding IPM practices were identified by interviewing teachers, extension personnel, experts and the sampled FFS farmers. Twenty possible solutions/suggestions for overcoming the problems were also collected by using the same procedure. The importance of the problem and the suggestions was measured by using Important Problem Score Index (IPSI) and Important Solution Score Index (ISSI) technique, respectively. The five most important problems as reported by the farmers ranked in the following order: i) need for much more labour, ii) lack of proper training for farmers about IPM, iii) lack of farmers knowledge regarding IPM practices, iv) availability of insecticides and v) complexity of IPM practices. Similarly, the five most common suggestions were i) establishment of more IPM field school, ii) arrangement of farmers practical training, iii) introduction of IPM practices into the school/college academic course, iv) increase the farmers awareness on environment pollution and v) to ensure proper supervision of extension worker. IPM is environment-friendly pest management system but due to its complexity need more knowledge and training. So, it is needed to give more emphasis in educational and motivational programme for increasing IPM practices for the farmers by the implementing agencies. DOI: http://dx.doi.org/10.3329/bjar.v37i1.11183 Bangladesh J. Agril. Res. 37(1): 121-128, March 2012
Profitability of BARI Released Potato (Solanum tuberosum L.) Varieties in Some Selected Locations of Bangladesh
Authors: Haque MA , Miah MA Monayem , Hossain S , Rahman MM
Published: July 2012

Potato is one of the important food crops in Bangladesh. Its demand is increasing day by day. The Tuber Crop Research Centre (TCRC) of BARI released 40 HYV potato varieties and disseminated them in the farmers fields through different agencies. But most varieties were not adopted well by the farmers due to unknown reasons. Therefore, an attempt was made to assess the level of adoption and profitability of BARI released potato variety at farm level. Data were collected from 150 randomly selected potato farmers from Munshigonj, Bogra and Comilla districts during January-February 2010. The results indicated that 48% potato areas were covered by Diamant variety, 16% by Cardinal, 22% by Granola, and the rest 14% areas were covered by Binella, Asterix, Provento, Felsina, Multa and Hira. The cost of BARI released potato cultivation was Tk 2, 10,629 and Tk 1, 84,135 per hectare on full cost and variable cost basis. The major share of total cost was for seed (42%) followed by fertilizer (21%) and human labour (14%). The average yield of potato was 26 t/ha with gross margin of Tk 1, 51,003 per hectare. The net return of potato cultivation was Tk 1, 24,509 per hectare. The benefit cost ratios were 1.59 and 1.82 on full cost and variable cost basis. Human labour, land preparation, seed, and irrigation had positive and significant effect on potato production. Nonavailability  of HYV seed at proper time, lack of technical knowledge, high price  of seed and fertilizer, infestation of insect and diseases, and lack of storage facilities were the major problems of potato production. DOI: http://dx.doi.org/10.3329/bjar.v37i1.11189 Bangladesh J. Agril. Res. 37(1): 149-158, March 2012
Effects of Ashwagandha (Withania somnifera) Root Extract On Some Serum Liver Marker Enzymes (AST, ALT) In Gentamicin Intoxicated Rats
Authors: Sultana Nayma , Shimmi Sadia Choudhury , Parash M Tanveer Hossain , Akhtar Jesmine
Published: July 2012

Background: Liver is an essential metabolic organ. It can be damaged due to prolonged use and higher doses of drugs, exposure to some chemicals, toxins, or infectious agents. Herbal plants as ashwagandha (Withania somnifera) may have free radical scavenging activity thereby can be used for the prevention and treatment of liver damage.Objective: To observe the effect of ashwagandha (Withania somnifera) root extract on gentamicin induced changes of some liver marker enzymes e,g serum aspartate amino transferase (AST ) and alanine amino transferase (ALT) in Wistar albino rats.Methods: This experimental study was carried out in the Department of Physiology, Sir Salimullah Medical College (SSMC), Dhaka from 1st July 2010 to 30th June 2011. A total number of 35 Wistar albino rats, aged 90 to 120 days, weighing between 150 to 200 grams were selected for the study. After acclimatization for 14 days, they were divided into control group (Group A) and experimental group (Group B). Control group was again subdivided into group A1 (baseline control, consisted of 10 rats) and group A2 (gentamicin treated control group, consisted of 10 rats). Again, experimental group (Group B-ashwagandha pretreated and gentamicin treated group) consisted of 15 rats. All groups of animals received basal diet for 22 consecutive days. In addition to this, group A2 also received gentamicin subcutaneously (100mg /kg body weight/day) for the last eight (15th to 22nd day) consecutive days. Again, group B received ashwagandha root extract (500mg/kg body weight/day, orally) for 22 consecutive days and gentamicin subcutaneously (100mg/kg body weight /day) for last eight (15th to 22nd day) days. All the animals were sacrificed on 23rd day. Then blood and liver samples were collected. For assessment of liver function, serum AST, ALT and bilirubin levels were estimated. All these tests were done by standard Laboratory technique. The statistical analysis was done by one way ANOVA and Bonferroni test as applicable.Results: The mean serum levels of AST and ALT were significantly (p<0.001) higher in gentamicin treated control group and in ashwagandha pretreated and gentamicin treated group in comparison to those of baseline control group.. Again, these levels were significantly (p<0.001) lower in ashwagandha pretreated and gentamicin treated group than those of gentamicin treated control group.Conclusion: Ashwagandha (Withania somnifera) root extract restored serum AST, ALT towards normal levels in gentamicin intoxicated rats which may be due to its free radical scavenging activity. Therefore it may have hepatoprotective effect. DOI: http://dx.doi.org/10.3329/jbsp.v7i1.11152 J Bangladesh Soc Physiol. 2012, June; 7(1): 1-7
Serum Zinc, Copper and Calcium Levels In Female Rheumatoid Arthritic Patients
Authors: Jelly Arifa Alam , Begum Shelina , Ferdousi Sultana
Published: July 2012

Background: Rheumatoid Arthritis is a chronic multi-system autoimmune inflammatory disease,  characterized by inflammatory synovitis involving symmetrical peripheral joints. Serum copper, zinc  and calcium levels are altered in Rheumatoid Arthritis.Objective: To observe serum zinc, copper and  calcium levels in patients with Rheumatoid Arthritis (RA).Methods: This cross sectional study was  conducted in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University  (BSMMU), Shahbag, Dhaka from January to December 2010. For this, 60 female patients with  Rheumatoid arthritis aged 30-50 years were included in the study group. The patients were selected  from outpatient Department of Rheumatology wing of medicine in Bangabandhu Sheik Mujib Medical  University (BSMMU). For comparison age and BMI matched 30 apparently healthy female were also  studied. Serum calcium level was measured by Colorimetric method. Serum zinc and copper was  measured by Spectrophotometric method. For statistical analysis, independent sample t test was  performed by using SPSS for windows version-12.Results: In this study, serum zinc and calcium  levels were significantly lower (p<0.001) and serum copper level was significantly higher (p<0.001) in  the RA patients than those of control.Conclusion: This study may conclude that hypozincemia and  hypocalcemia and hypercupremia occur in RA. Therefore early detection of these micronutrient  abnormalities may be helpful for the physicians to prevent various complications in RA patients. DOI: http://dx.doi.org/10.3329/jbsp.v7i1.11155 J Bangladesh Soc Physiol. 2012, June; 7(1): 18-22
MANAGING IT WORKERS
Authors: Łubieńska Katarzyna , Woźniak Jacek
Published: July 2012

The text analyses the issue of motivation in software engineers. It bases on the experiences of one of the authors, and on preliminary results of qualitative and quantitative research gathered from 300 software engineers working in the IT financial service sector in Poland. It reviews main approaches to software specialist motivation found in the scientific and practical literature. It critiques some approaches to motivation of software specialists for the long-term consequences of using the motivators that they focus on. It shows that research based on P. Glen’s model (2003a) analyses only hygienic factors (as described by Herzberg) that can hinder the state of flow (Csikszentmihalyi 1975), which is characteristic of internally motivated software specialists. There are no analyses which would show how to secure long-term hygienic factors in the management of IT specialist motivation. Recommendations on long-term hygienic factors form a significant part of the text.
Risky Recreation: Synthetic Cannabinoids Have Dangerous Effects
Authors: McGuinness Teena M. , Newell Donna
Published: July 2012

Use of synthetic marijuana (also known as
spice, K2, aroma,
and
eclipse
) is often viewed by young people as harmless recreation. Until recently, the substance was freely available in U.S. convenience stores and head shops, and it is still available via the Internet. Emerging evidence shows a wide range of responses to the drug, including paranoia, aggressive behavior, anxiety, and short-term memory deficits. Synthetic cannabinoids are not currently detectable via standard toxicology tests. Recognition and management of synthetic cannabinoid use are discussed.
The Study of Ball and Plate System Based on Non-Linear PID
Authors: Sun Sheng Qi , Li Lin
Published: July 2012

It is difficult to build a precise mathematical model for complex ball and plate system and many intelligent algorithms’ programming are larger, so we make use of the non-linear PID controller to control actual system and realize the point to point control and circular trajectory control of the ball. The experiment results show that the control method of non-linear PID could ensure the movement accuracy of the ball, achieve the performance of control process, and have better control effect than traditional PID.
Finite Element Analysis of Flextensional Transducer with Slotted Shell
Authors: Chen Si , Lan Yu
Published: July 2012

The study of low frequency, small size transducer was an important aspect for the development of the underwater acoustic transducer. The Class Ⅳ flextensional transducer was a typical low frequency, high-power and small size transducer. For decreasing its resonant frequency in the case of small size, a flextensional transducer with slotted shell was analyzed using finite element software ANSYS. A comparison between the flextensioanl transducer with slotted shell and the Class Ⅳ flextensional transducer was made. The maximum size of the shell is 200mm. The transmitting voltage response of the transducer reaches to 131dB with resonant frequency 600Hz in water. The transducer could radiate at low frequency with small size of the shell.
Kinematics Simulation and Control System Design of Serial Robot Based on ADAMS and Pro/E
Authors: Fan Hong Mei
Published: July 2012

Mechanic dynamic analysis software ADAMS was used to build a virtual prototype of a 6-D serial robot, and the kinematics simulation was performed. The virtual prototype model provides the theoretic foundation and main parameters for the control system design, production and application in experiment.
The Synthesize and Properties of Aquosity Polyester Acrylate Nanoemulsion
Authors: Yan Cui , Ma Chang Zheng , Zhang Guang Cheng , Qi Feng Jun
Published: July 2012

A new type of polymer nanoemulsion has been synthesized by molecular self-assembly technique. The emulsion particle size that can be clearly observed by CENT is less than 100nm. The results of these measurements support the idea that polyacrylate molecular segments assemble with polyester segments. Then based on the polymer nanoemulsion, waterborne block type exterior architectural nanopaints have been prepared. The waterborne coatings behave good water-resistance, physics-mechanical properties and decorative and protective performance. Scrub resistance improves greatly which can reach 10000 times.
Research on Ytterbium Doped Phosphate Glasses
Authors: Fan Li Dan , Wu Li Hua
Published: July 2012

Ytterbium doped laser glasses is generally preferred in the updating of various laser material because it have excellent mechanical and stability of thermal and optical properties. In this paper, experiments are performed through changed the concentrations of laser glasses medium and Ytterbium ions based on current research. The different of the concentrations and thickness of Yb3+ doped phosphate glasses have been investigated in order to gain best spectroscopic properties and stability of thermal and optical properties.
A New Design of Underwater Robot Fish System Using Shape Memory Alloy
Authors: Huang Pei Hua , Wang Jian
Published: July 2012

The bionic structure of an oscillatory propulsion system was discussed in this paper, This structure was contrived from sufficient analysis by the anatomical structure of a fish, Shape Memory Alloy was used to apply its power. Of course, we simplified the oscillatory propulsion system. Finally, we established the quantitative relationship among parameters depending on the torque balance equation.
Investigation of the Temperature Distribution in the Lithium-Ion Battery for Pure Electric Vehicles
Authors: Zheng Liang , Wu Bin , Xu Guo Qing
Published: July 2012

Lithium-ion batteries have more excellent performance than other types of batteries, thus it is widely used in electric vehicles. Using batteries as the main power supplier does inevitably generate a lot of heat which not only deteriorates the batteries, but endangers the safety of the vehicle. In this paper, the temperature distribution of the batteries in the pure electric vehicles was investigated to minimize the heat generated in the batteries. The finite element formulations of the 3-D heat conduction equation of the battery were established for both steady and transient states. Then the finite element simulations were developed to investigate and optimize the temperature distribution of the battery and the battery pack. A parametric study was completed such that the heat generated in the battery pack can be minimized.
Evaluation of Tensile Properties of Pressure Vessel Materials by Shear Punch Test Method
Authors: Ramesh T. , Prakash Raghu V. , Suresh S. , Raju N.
Published: July 2012

A shear punch test is a very useful small specimen test method for evaluating the mechanical properties of in-service components, in view of the requirements of small size sample material. This paper presents the results of shear punch tests on five grades of steels used in boiler construction, along with the correlation with yield stress and ultimate tensile stress obtained ASTM standard specimens. The design of the shear punch fixture and procedure to carry out the shear punch test is also highlighted.
Visualization of Supersonic Non-Newtonian Liquid Jets
Authors: Matthujak Anirut , Kasamnimitporn Chaidet , Sittiwong Wuttichai , Pianthong Kulachate
Published: July 2012

This paper describes the characteristics of supersonic non-Newtonian liquid jets injected in ambient air. The main focus is to visualize three types of time-independent non-Newtonian liquid jet and to describe their behaviors. Moreover, comparisons between their dynamic behaviors with Newtonian liquid jet are reported. The supersonic liquid jets are generated by impact driven method in a horizontal single-stage power gun. Jets have been visualized by the high speed digital video camera and shadowgraph method. Effects of different liquid types on the jet penetration distance, average jet velocity and other characteristics have been examined. From shadowgraph images, the unique dynamic behaviors of each non-Newtonian liquid jets are observed and found obviously different from that of the Newtonian liquid jet. The maximum average jet velocity of 1,802.18 m/s (Mach no. 5.30) has been obtained. The jet penetration distance and average velocity are significantly varied when the liquid types are different.
Research on Simulation System of Aero-Generator
Authors: Zang Xiao Jie , Song Jian
Published: July 2012

This paper presents a kind of simulation program of aero-generator, that inverter adopts a computer-controlled manner to simulate actual working features of aero-generator, based on test platform status of aero-generator. And design of the structure of simulation system , analyze the working principle of aero-generator, and then set up simulation model of three-stage brushless aero-generator under SIMULINK. Finally ,simulation results show the accuracy of this program.
Quasi-Static Test of Reinforced Concrete Shear Wall with Low Concrete Strength and Reinforcement Ratio
Authors: Deng Kai Lai , Pan Peng , Shi Yuan Yuan , Miao Qi Song , Li Wen Feng , Wang Tao
Published: July 2012

A large number of reinforced concrete (RC) buildings constructed in the 1970s, whose main structural form is fish-bone shear wall, are still used in Qiansanmen area of Beijing. Due to the economical and technical limitation at the time, both the concrete strength and reinforcement ratio are far from satisfying the requirements given in the current seismic design code for concrete structures. In order to investigate the seismic performances of the wall with the low concrete strength and reinforcement ratio, four RC shear wall specimens were constructed and tested. Quasi-static tests considering large axial compression ratio were carried out, and the stiffness, the strength and the energy dissipation capacity of the RC shear walls are investigated. Test results suggest that the wall with low concrete strength and reinforcement ratio has low strength and poor deformation capacity, indicating the necessity of strengthening.
Experimental and Numerical Study on Torsional Behavior of Precast Concrete Screw Pile Body
Authors: Li Xin , Liang Li
Published: July 2012

Precast concrete screw pile is a new kind of pile foundation. Because the pile bears very large torsion in construction, the torsional properties of pile body including cracking torsion, ultimate torsion and torsional deformation were studied in this paper in order to improve the anti-torsional ability of precast concrete screw pile. Experimental method and numerical method are used to research the torsional behavior of precast concrete pile body. Experimental and numerical results of cracking torsion, ultimate torsion and relationship between torsion and angle of twist per unit length of different specimens are obtained. In addition, five factors of strength level of concrete, degree of prestress, distance of spiral hoop, concrete cover and diameter of spiral hoop influencing on torsional behavior of precast concrete pile body are researched by orthogonal numerical test. The rational finite element model and solution method are concluded for calculating the torsional behavior of concrete pile. Moreover, the rational pile type and design parameters of precast concrete screw pile are obtained.
Whole-Span and Whole Length Pre-Stress Loss Monitoring Technique Study in Bonded Pre-Stressed System
Authors: Zhang Ji Bin , Lin Song Tao , Gao Juan
Published: July 2012

The load of pre-stress structure comes from stretching of steel strand, but the stress built on the steel strand would be lost. The lost causes many problems on the structure, such as pre-stress uneven and margin of safety reduced. Monitoring stress lever on the steel strand can provide information of the structure, and then expert can estimate the behavior under load of structure. It is hardly to monitor the whole-span and whole length of steel strand by traditional senses and method, because of measure range, protection and interference of electromagnetic environment. A novel method based on Optic Fiber Bragg Grating (OFBG), which mentioned in the article, provides a successful experience on the monitoring of pre-stress loss in whole-span and whole length.
The Experimental Research of New Lightweight Steel Composite Slab
Authors: Liu Dian Zhong , Tian Shi Hao
Published: July 2012

The new composite sandwich slab of the cold formed thin-walled steel and lightweight aggregate concrete is studied. The composite sandwich slab is a skeleton of cold formed thin-walled steel, cast-in-situ lightweight aggregate concrete, built-in benzene board as a sandwich layer. The composite sandwich slab has a light weight, seismic performance is good, and construction period is short of advantage, can effectively solve poor shortcomings of the steel structure fireproofing performance and corrosion resistance, and can effectively improve the whole and local stability of the steel structure. The composite sandwich slab bearing capacity of the cold formed thin-walled steel and lightweight aggregate concrete is analyzed using simple plastic theory. The deflection to consider interface slip of the composite slab is computed. The composite sandwich slab is tested statically; the failure mechanism of the slab is analyzed. The load-deflection curve, load-strain curve are obtained. The sandwich rate of the slab on the influence of the bearing capacity is analyzed using the finite element method, and theoretical with experimental results comparatively analyzed.
Research on Temperature Influences in Cable-Stayed Bridges’ Health Monitoring
Authors: Yao Chang Rong , Li Ya Dong
Published: July 2012

The health monitoring for long-span bridges has become a hotspot in civil engineering. However, because of the complexity and particularity in bridge structure, monitoring variables are greatly influenced by environmental factors, which results in more difficulties in evaluation. The paper analyzes structural responses in different temperature fields, and the results show that effect of temperature difference among members and temperature gradient are remarkable on structures. The results may be of reference for formulation of bridge health monitoring strategies.
Improving Preparation of Porous Ceramic Foamed by Microbe
Authors: Zhu Hua Qing , Chen Yun Xia
Published: July 2012

Preparation of porous ceramic body foamed by microbe is prone to structure defects such as inequality of pore size and distribution, crack, contraction deformation, etc. Four-level orthogonal tests based on three improving factors such as water content(WC) and carboxymethyl cellulose (CMC) and stirring time(ST) were carried out to improve the method of preparing porous ceramic body foamed by microbe at ordinary tempreature. It is concluded that water content is the key improving facor followed by stirring time and CMC content, and the optimized formula could be A3B3C1 or A3B4C2.
The Finite Element Analysis and Experimental Study of Fly Ash Embankment Reinforcement
Authors: Wang Hu Mei , Wang Yang , Huang Lin
Published: July 2012

This paper presents the effect of two-directional reinforced with geogrid on the performance of embankment, and carries out model experiment and numerical simulation on fly ash embankment. Finally, the curve of relationship among the embankment deformation, the amount of reinforcement and reinforced position was obtained. In addition, the optimum geogrids-reinforced project was also disscussed. The disscussion has some positive effect on the design of reinforced embankment of fly ash.
Discussion of Ceramsite Concrete Shaped Column in a Structural System
Authors: Zhu Jun Guang , Huang Xu , Zheng Rong Yue
Published: July 2012

Thermal insulation building materials that is both lightweight and high strength is the key to the future of China's construction sector in achieving energy conservation. In terms of building construction, when comparing lightweight aggregate concrete to that of ordinary concrete, light weight aggregate is lighter, has a large structure span, good seismic performance, saving cost and other advantages; Ceramsite concrete is a type of lightweight aggregate concrete. Also because the shaped column is not ridge, is able to increase the amount of usage area, due to being light is energy efficient, therefore is in line with the wall reformation and is thus preferred. Upon combining these two characteristics, the analysis of the Ceramsite concrete shape columns properties and its prospect for development.
Relationships between Compressive Strength and Microstructure in Mortars with Iron Ore Tailings as Fine Aggregate
Authors: Yu Lei , Zhang Jin Xi , Mu Kai
Published: July 2012

In this study, the effect of Iron Ore Tailings (IOT), as fine aggregate in mortars, on microstructure and compressive strength with 14 days was observed on mortar specimens. The replacement ratios for IOT as fine aggregate were 60% and 100%. Pore structure parameters were measured with the instrument of MIP and calculated with corollary software. Situations of interface between aggregates and hard cement pastes were observed by FEI quanta 200 SEM. Consequently, it was seen that IOT can improve mortar’s compressive strength because of tighter interface between aggregate and hard cement paste and enhanced porous structure related to the finer structure of IOT comparing to reference sand.
Research of EMI Structural Health Monitoring Based on BP Neural Networks
Authors: Xu Fu Hou , Wen Dong Dong , Zhang Yu Xiang , Li Hua Cheng
Published: July 2012

Based on the coupling characteristic of piezoelectric ceramics (PZT) and electro-mechanical, impedance changes were measured by the impedance analyzer. Aluminum plate’s impedance response under different load conditions was analyzed with electromechanical impedance technique. BP neural networks were established to identify the structural damage status and the RMSDR was calculated as neural network input data, then the networks was trained and validated. Experiment results show that the trained network can successfully identify the structural load state.
Bitumen Sliding Joints for Friction Elimination in Footing Bottom
Authors: Čajka Radim , Matečková Pavlina , Smirakova Martina
Published: July 2012

Use of a sliding joint is an effective method to decrease the stress in foundation structure where there is a horizontal deformation of subsoil (areas afflicted with underground mining) or horizontal deformation of a foundation structure (pre-stressed foundations, creep, shrinkage, temperature deformation). A convenient material for a sliding joint is a bitumen asphalt belt. Experiments for different types of bitumen belts were undertaken at the Faculty of Civil Engineering - VSB Technical University of Ostrava in 2008. Since 2011 an extension of the 2008 experiments has been in progress and the shear resistance of a slide joint is being tested as a function of temperature in a temperature controlled room. In this paper experimental results of temperature dependant shear resistance are presented. The result of the experiments should be the sliding joint shear resistance as a function of deformation velocity and temperature. This relationship is used for numerical analysis of stress/strain relation between foundation structure and subsoil.
Wavelet Transform Applied on Vehicle Air Flow Meter (AFM) Signal De-Noising
Authors: Feng Guan Ming , Zhu Liang Rong , Wu Zhuang Wen
Published: July 2012

In engine compartment, it is difficult to eliminate the effect of interfering signals on vehicle AFM signal by the traditional processing method. According to the characteristic of AFM signal, this paper decomposed the noise signal for 4 layers by selecting Daubechies (db5) wavelet in Matlab based on wavelet theory. After decomposing, and then employed the soft-threshold de-noising method to eliminate noise. At last this paper used the inverse wavelet transform to reconstruct signals for signal de-noising and rebuilding. The test results show that this method can eliminate the noises of AFM signal effectively.
FEM Analysis on Tensile Force of Geosynthetic Reinforcement Arranged in GRS-RW Considering Variable Loading Rate
Authors: Li Fu Lin , Peng Fang Le
Published: July 2012

The combined effects of the rate-dependent behavior of both the backfill soil and the geosynthetic reinforcement have been investigated, which should be attributed to the viscous property of material. A nonlinear finite element method (FEM) analysis procedure based on the Dynamic Relaxation method was developed for the geosynthetic-reinforced soil retaining wall (GRS-RW). In the numerical analysis, both the viscous properties of the backfill and the reinforcement were considered through the unified nonlinear three-component elastic-viscoplastic model. The FEM procedure was validated against a physical model test on geosynthetic-reinforced soil retaining wall with granular backfill. Extensive finite-element analyses were carried out to investigate the tensile force distributions in geosynthetic reinforcement of geosynthetic-reinforced soil retaining wall under the change of loading rate. It is found from the analyses that the presented FEM can well simulate the rate-dependent behavior of geosynthetic-reinforced soil retaining wall and the tensile force of geosynthetic reinforcement arranged in retaining wall.
Research on the Cavern Stability and Rock Fracture with Different Joint Groups
Authors: Ma Hai Ping , Zhu Wei Shen , Yu Song , Wang Jing
Published: July 2012

The numerical simulation using DDARF was carried out to analysis the rock samples with two and four cracks under uniaxial loading condition. Contrastive research was made about the fracture process analysis of rock mass with joints sets at the three different angles. The rock stability with difference of joint rock mass was compared when the lateral coefficient of initial stress varied. It is shown that distribution of joint groups will bring effects on rock surroundings in controlling deformation, stress status and stability.
Reliability Analysis for Rotor System with Oil Whip and Resonance Based on Frequency
Authors: Su Chang Qing , Zhang Yi Min
Published: July 2012

Parameter uncertainty of general systems is inherent in most engineering problems. Based on the regularity of oil whip and resonance for rotor system, the reliability problem of rotor system with oil whip and resonance is studied by applying random perturbation technology and reliability theory considering the correlation of the multi-order natural frequency. The reliability mode and the failure probability of rotor systems are defined. The second-order joint failure probability is obtained by using the numerical integration method. The presented method provided the theoretic basis for the reliability design of the rotor system. A numerical example demonstrated that the proposed method is effective.
A New Reliability Analysis Method Based on Stability Reliability for Closed-Loop Control System
Authors: Guo Xiao He , Jiao Zong Xia , Wang Shao Ping
Published: July 2012

Considering stability is the necessary condition for closed-loop control system to work properly, a new function reliability analysis method by inducting and defining the concept of stability reliability was proposed to describe the function reliability of closed-loop control system completely. As an example, the stability reliability calculation method and process to analyze the function reliability of a flight autopilot were demonstrated.
Black Box System Multi-Objective Optimization Based on Design of Experiment
Authors: Sui Tian Zhong , Wang Lei , Cheng Dong Mei , Cui Hong Wen
Published: July 2012

In this paper, a multi-objective parameter optimization model based on experimental design and NN-GA is established. In this method, utilizing experimental design principle to deal with test project and applying NN to map and using Pareto genetic algorithm to optimize, multi-objective parameter optimization is accomplished, in which the high nonlinear mapping ability of neural network model, the global research ability of genetic algorithms and multiform choice about the test points according to experimental demand are utilized synthetically. A Pareto-optimal set can be found in specify region. The method can be applied broadly and it needn’t the concrete mathematic model for different optimizing demand. For virtual devices and products, the virtual experiments can be realized by parameter-driven characteristic.
Strength Optimization Design of a Helical Hydraulic Rotary Actuator
Authors: Yang Yu , Guo Xing , Yang Shu Dong , Xu Tao
Published: July 2012

A helical hydraulic rotary actuator for part-turn motion control is presented. Because of its compact structure and large output torque, strength study for the helical hydraulic rotary actuator becomes very necessary. Using AWE, influences of multi-start thread engagement length, thread start number, spline pressure angle and piston material on strength of the actuator’s key parts are studied in depth, so as to optimize the actuator’s strength and structure. The results show that the influences of nut width, thread start number and piston material on multi-start thread root strength of nut are notable, the influence of pressure angle on spline tooth root strength of output shaft is visible, and stress concentration on multi-start thread root and spline tooth root is very obvious.
Analytical Target Cascading Based on the Quadratic Exterior Penalty Method for Complex System Design
Authors: Zhang Xiao Lin , Jiang Ping , Zheng Jun , Li Ying
Published: July 2012

Analytical Target Cascading (ATC) is a method to partition the optimization of a complex system into a set of subsystem optimizations and a single system optimization according to the structure of the complex system, and coordinate subproblems toward an optimal system design. The constructed new optimization problem owns a hierarchical structure, which better matches the real organization structure of complex system design, so the ATC method provides a promising way to deal with the complex system. For each design problem at a given level, an optimization problem is to minimize the discrepancy between its responses and propagated targets. In ATC, for feasibility of subproblems, the target-response pairs are translated into the relaxation terms in which the weight coefficients is used to represent the relative importance of responses and linking variables matching their corresponding target, and achieve acceptable levels of inconsistency between subproblems when top level targets are unattainable in the hierarchical decomposition structure. Furthermore, weighting coefﬁcients influence convergence efficiency and computational efficiency so that the suitable allocation of weight coefficients is a challenge. This paper adopts the Quadratic Exterior Penalty Method to deal with the weight coefficients that achieve solutions within user-specified acceptable inconsistency tolerances. Meanwhile, the method prototype will be tested on a numerical example and implemented using MATLAB and iSIGHT.
The Action Mechanism of the Layering User Demands in the Product R&D Process
Authors: Li Wei Zhan , Yang Xian Ying
Published: July 2012

Combining the Maslow’s theory of the five hierarchy demands and the layering consume market diversity, explored the innovation opportunities and the methods from the levels of the different users’ demands, and analyzed the action type in product design, research and development (R&D) process. According to the action type of the layering demands in the process, depending on the product types described the action mechanism of the layering user demands. This mechanism plays the guiding and controlling role in the plan, innovation, design and design management stages of a product development. This research provided an important innovative method for different product design in the R&D process. The research results give a reference for the new product innovation and decisions especially, meanwhile it help us to find the trend of the next generation product.
Short Fatigue Crack Propagation Threshold of Railway LZ50 Axle Steel
Authors: Zhao Yong Xiang , He Z. , Yang B.
Published: July 2012

Collective short fatigue behaviour nearby material micro-structural barrier threshold is experimentally observed for the smooth specimens of Chinese railway LZ50 axle steel. Effective micro-cracks which result in the specimens’ failure were initiated from the material ferrite particles on the surfaces of the specimens. Four elements i.e. crack size, orientation angle, and the two crack tip orientation angles should be contained for each micro-crack. The collective micro-crack behaviour should be described by an equivalent dominant effective short fatigue crack (ESFC) concept using an ESFC theory. And an equivalent method is then developed with an equivalent growth driving energy concept. A random modeling of the equivalent dominant ESFC growth rates is further constructed for describing the random behaviour of the collective ESFCs nearby the material micro-structure barrier threshold. And the kinetic threshold is subsequently conducted from the modeling.
Research on Fault Diagnosis Based on BP-SOM Hybrid Algorithms for NC Machine
Authors: Deng Chao , Dong Wen Long , Wang Yuan Hang , Xiong Yao
Published: July 2012

NC machines are more and more widely used in manufacturing industry. As the key equipments in the factory, NC machines should be closely monitored to avoid faults. Therefore, the research on multi-function diagnosis based on BP-SOM is discussed for NC machine in the paper. Taking the precision data as the basic data for diagnosis, the research used BP and SOM algorithms to build up diagnosis models. As a result, the research has accomplished the diagnosing process and acquires good simulation output, which resembles with the real fact.
An Optimization Method of the Heavy Machine Cutting Parameters
Authors: Deng Chao , Ma Chao , Xiong Yao , Wang Yuan Hang
Published: July 2012

This paper analyzes the machining process of CNC machine tools, and builds an optimization model of the machining process parameters based on the mechanical vibration and the operational research. The model mixed genetic algorithm and particle swarm optimization (PSO) is built. It proposes an optimization algorithm that has higher convergence precision and execute ability to solve engineering problem with nonlinear and multi-extremum. According to case study, it proves the correctness of the model and the efficiency and high-performance nature of the designed optimization algorithm. It also appears the efficiency to solve the common engineering problems by the intelligent optimization algorithms.
Optimization of Condition-Based Maintenance Policy for Deteriorating System Based on Monte-Carlo Simulation
Authors: Ge En Shun , Li Qing Min , Huang Ao Lin
Published: July 2012

Condition-based Maintenance (CBM) can not only efficiently improve the performance of deteriorating system but also guarantee the system operation safety. This paper assumes that the system state is periodically inspected, and a preventive maintenance is performed if the degradation level exceeds a threshold. The effect of maintenance is imperfect, which means that maintenance can restore the system state to somewhere between as good as new and as bad as old. The algorithm is presented to get the solution of long run cost based on Monte-Carlo simulation, and the joint optimization of inspection rate, the threshold value and the number of preventive maintenance activities is investigated for the minimization of long run cost rate. A case study is given to show the procedure of the maintenance model and simulation. Therefore, the correctness and rationality of the model are proved.
Distribution of Time Between Failures of Numerical Control System Based on Censored Data
Authors: Dai Yi , Yang Xue Zhi , Ji Ning
Published: July 2012

The calculation of mean time between failures (MTBF) is of significance in reliability engineering. The precondition before calculation of MTBF is to make sure what failure model the numerical control (NC) system follows. For different distributions, the corresponding calculation methods of MTBF are always different. Undertaken a 2 year period of timing censored test with replacement of NC lathe, authors apply a type I censored likelihood function to make the distribution fitting of time between failures of NC system. The tests of goodness-of-fit applying Hollander’s method demonstrate that the time between failures of NC system follows the Weibull distribution. The conclusion not only deeply analyzes the NC system failure law, but also establishes the basis of calculation for the mean time between failures of NC system based on censored data with replacement.
The Optimal Combination Research of System Configuration and T&M Policy of Standby Safety System
Authors: Hu Z.Y. , Xie Li Yang , Zhang Xiao Jin
Published: July 2012

The unavailability equations of several aging scenarios of standby safety component are derived and the risk of standby safety system is quantified. The different maintenance strategies are adopted for no aging scenario and several aging scenarios respectively. The two kind of test and maintenance (T&M) policies are adopted for no aging scenario and several aging scenarios. A numerical example is introduced for the illustration. The system unavailabilities under different configurations of parallel safety system and T&M policies are computed and compared. It can be derived that the combination of different T&M policies and configurations is significant effect on the risk of standby safety system and optimal STI and T&M interval.
Research on Two Ends Energy-Absorbing Structure of High-Speed Railway Passenger Car Body
Authors: Zhang Zhi Xin , Xiao Shou Ne , Yang Guang Wu , Shang Xiu Min
Published: July 2012

Based on characteristics of high-speed trains, a special passive protective structure was designed and simulated by the non-linear FEA code LS-DYNA. The two-step energy-absorbing structure fixed on the cab side and the similar function structure on the other end were studied. It was proved that the two-step structure deformed orderly and had an energy absorbing capacity of 3.4MJ which could protect the cab effectively and that the rear end low stiffness zone had an energy absorbing capacity of 6.5MJ which also could protect the integrity of the passenger areas. Three typical train-to-train collision scenarios were studied by full-scale FEA method.
A Study on the 6-6 Stewart Parallel Mechanism Dynamics in ADAMS
Authors: Han Xing , Li Chang , Yu Xiao Guang , Zhao Guang Bing
Published: July 2012

In this paper, it proposes an effective method for 6-6 Stewart parallel mechanism dynamics analysis in ADAMS. Firstly, it builds a virtual model in ADAMS/View, using spline function and self-defining function to define loads and constraints, through the follow-up dynamic simulation, the positive solutions and inverse solutions are solved conveniently, and this can provide a foundation for analyzing the parallel mechanism’s operability and space path line. Secondly, it uses secondary developing technology (APDL) to program a parameterized virtual model, which can give a credibility way to analyze the influence of random errors on the mechanism mobile. In short, it needn’t to calculate complex mathematic model as that in the past, yet this new method proposed provides a definite theory foundation and contains well application values for further study.
Research on Profit Model of Diesel Engine Products-Services System
Authors: Liu Zong Hu , Song Dan Dan , Su Jian
Published: July 2012

While PSS is fundamental for the development of solution oriented partnerships, the stakeholders’ distribution of profit is not defined an operational paradigm yet. In this article, we provide a brief overview of the diesel engine in the area of Product Service Systems. Firstly, we establish the model of Diesel Engine PSS, when we analysis the product features of diesel engine and the features of PSS for diesel engine. The application of PSS in diesel engine area may be different from other manufacturing, but the intrinsic complexity of PSS, which include Convenient, science and the economy, can be proved for the stakeholders. So then we summarize the stakeholders of PSS, and understand the relationship of stakeholders’ profit structure. Finally, we design the profit model of diesel engine PSS. The main content is that how to get the quantization of the stakeholders’ profit and the balance the profit model of diesel engine PSS which can decide to the trade of diesel engine products-services smoothly.
Wear Life Prediction for a Large Diameter Spool Valve
Authors: Xia Kui , Yang Shu Dong , Lei Ting , Wu Liang
Published: July 2012

Life prediction for a component can’t instead of its life tests, even so it has a very important guiding significance for the optimization design and material selection of the component, and it can decrease great loss caused by design mistakes, also possibly avoid detours, especially on initial development stage. It also is an important stage of the lifecycle design of a component. According to a certain working condition, this paper predicts the wear life of a large diameter hydraulic directional spool valve with 2-position 4-way for the hydraulic system of a high speed winch, combined with the surface micro-topography of the valve body and spool, and influence factors to the fit clearance changing caused by wear, such as shaping form errors, lateral force, matching materials, hydraulic medium and so on. The result shows that the wear life of the large diameter spool valve is more than 10 million times. The prediction provides a theoretical basis for the independent development of this valve, and has a certain reference for the design of this kind of components.
Structural Characterisation of Cellulose and Nanocellulose Extracted from Mengkuang Leaves
Authors: Sheltami Rasha M.El. , Abdullah Ibrahim , Ahmad Ishak
Published: July 2012

Nanocellulose was isolated from mengkuang leaves (Pandanus tectorius) by using concentrated sulphuric acid. The structural analysis of the leaves at different stages of treatments was performed by fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Transmission electron microscope (TEM) was used to investigate the dimensions of the isolated nanocellulose. The FTIR and XRD results indicated that the hemicelluloses and lignin were removed extensively in the extracted cellulose and nanocellulose, and the crystallinity were increased after removing these components. The TEM image showed that the diameter of isolated nanocellulose between 5-25 nm. The isolated nanocellulose may have applications in the fields of nanocomposites.
Synthesis and Battery Studies of Sodium Cobalt Oxides, NaCoO2 Cathodes
Authors: Samin Nur Khairani , Roshidah Rusdi , Kamarudin Norashikin , Kamarulzaman Norlida
Published: July 2012

Sodium based batteries presented a new and promising battery system. This work attempted to develop NaCoO2 material using a new sol-gel method. The characterization of this sodium based material was done by using Thermogravimetric Analysis (TGA), X-Ray Diffraction (XRD) and Field Emission Scanning Electron Microscopy (FESEM). Cyclic voltammetry showed that the material exhibit reversible oxidation and reduction peaks which meant that a sodium based battery was possible for this material. Electrochemical charge-discharge profile was performed to study the voltage plateaus exhibited by the material. It showed discharge plateaus of between 3.2 to 2.3 V and another plateau at 0.6 V.