bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimal Motion Planning for the Teaching Experimental Mobile Manipulator
Authors: Zhou Huai Ping , Ge Ping , Fang Yong
Published: November 2011

An optimal motion planning based on minimum principle is presented to address the motion problem of the mobile manipulator in a sort of experimental system. In view of the characteristic of the practical experimental apparatus, the model of the manipulator is deduced based on the kinetic analysis and mathematic method. An optimal control scheme is then investigated to deal with the optimization problem of the motion planning for the manipulator, so as to guarantee the demand of the teaching experiment. Simulation verifies the control performance of the optimal control scheme for the optimal motion planning of the manipulator, and it helps improve the teaching experiment effect.
A Technology Based on Image Processing for the Bridge Crack Measurement
Authors: Xu Bing , Yin Guan Sheng , Liu Xiao Wei
Published: November 2011

This paper gives a non-destructive and non-contact inspection way based on image processing which is introduced to detect bridge cracks. System architecture is also introduced and key algorithms in crack image processing is studied. These key algorithms are: image gray scaling, image enhancement, image strengthing, gap survey and so on. In the end such method is used to measure actual gap and the reliability of such method on bridge inspection has been verified with the results.
Cotton Fiber-Reinforced Polypropylene Composites
Authors: Lin Tao , Wang Zheng , Guo Wen Jing
Published: November 2011

Cotton stalk is a by-product of cotton planting process, and a great resource as a raw biomass material for manufacturing value-added composite products. The fine structure and fiber size of the cortex, xylem of the cotton stalk were studied in this paper. In addition, a new method for the processing of cotton stalk filament was developed. Composites consisting of polypropylene (PP) and cotton stalk filament were prepared by hot pressing. The effects of PP content and compressing temperature on the mechanical properties of cotton stalk filament /PP composites were studied. The results show that elevated temperatures, all of the composites are substantially stiffer and stronger than that at lower temperature. PP content improves the intensity and adhesion of composites. Simultaneous optimization of composites properties indicates that the composites with PP content of 40% and the compressing temperature of 195°C would sufficient meet the requirements of the GB/T 4897.1-2003 standard. Bio-renewable materials such as cotton stalk can be used as reinforcing materials for plastic composites.
Experimental Modal Analysis of Large Vibrating Screen with Hyperstatic Net Beams Structure
Authors: He Xiao Mei , Liu Chu Sheng
Published: November 2011

A vibration test and modal analysis has been completed, in order to improve the use reliability and extend service life of the large vibrating screen. Accurate natural frequency, modal shape, modal damping and some other modal parameters is got in the presented work. The result shows that there is one order frequency near working frequency of the vibrating screen and the modal shape is whole torsion around thexaxis and the discharge end’s bend alongzaxis. This order frequency can increase the elastic deformation of the screen surface in the four horns points and change the materials movement speed which makes the moving of the materials nonuniform. We also know that the bend displacement of the discharge end is larger which indicates that the stiffness of this part is smaller. So the structure of the discharge end needs to be modified. The analysis result also demonstrates that the part of the side plate near the feed end has a larger vibration, thus a further stress analysis of the side plate should be made. The analysis result of the modal test is used to correct the finite element theory model, to make the theory modal reasonable, thus a further dynamic optimization of the vibrating screen can be finished easily.
A Grey Correlation Model for Analyzing Ultimate Bearing Capacity of Large Diameter and Super-Long Pile
Authors: Tu Jie Wen , Tang Ai Ping
Published: November 2011

Large diameter and super-long pile has found abroad application in high buildings, super high buildings, large bridges and port engineering, and its ultimate bearing capacity is increasingly demanding. Its ultimate bearing capacity is affected by many kinds of uncertainty factors, which is a complex grey analysis program. The influencing factors are analyzed by grey system theory such as pile diameter, pile length, socket length, the length to diameter ratio, the socket length to diameter ratio, rock strength and rock coefficient of weathering. The grey correlation analysis is combined with the tested statistical data of 19 large diameter and super-long piles in Zhejiang province based on the grey correlation model. With the objective to overcome the lack of objectivity in calculating correlation degree of the grey correlation analysis, this paper has improved the calculated formula of the correlation degree based on the distance analysis method. The paper has get and compared the corresponding result of the correlation degree and its rank of various influence factors with the improved calculated formula and the original formula respectively. The influence advantage factors found by grey correlation analysis, and the results can provide important reference for the future theoretical research and design application of large diameter and super-long pile, and show that the grey correlation method is effective and reliable.
Low Cycle Tension-Tension Fatigue Properties of 316L Stainless Steel Thin Sheets
Authors: Liu Yong Jie , Wang Qing Yuan , Tian Ren Hui , Zhao Xiao
Published: November 2011

In this paper, tensile fatigue properties of 316L stainless steel thin sheets with a thickness of 0.1 mm are studied. The tests are implemented by using micro mechanical fatigue testing sysytem (MMT-250N) at room temperature under tension-tension cyclic loading. The S-N curve of the thin sheets descends continuously at low cycle region. Cyclic σ-N curve and ε-N curve are obtained according to the classical macroscopical fatigue theory. The results agree well with the experimental fatigue data, showing that the traditional fatigue research methods are also suitable for description of MEMS fatigue in a certain extent. The effect factor of frequency was considered in this study and the results show that the fatiuge life and the fatigue strength are increased as loading frequency increasing.
Dynamic Analysis and Optimization of Automatic Tape-Laying (ATL) Machine for Cylinder Components
Authors: Zhang Hui Feng , Guan Li Wen , Li Tie Min
Published: November 2011

The structure of an automatic tape-laying (ATL) machine for cylinder components is introduced. The FEM model is established and static stiffness, modal, harmonic response analysis are performed. The improvement scheme is given based on the above analysis result, with better static and dynamic characteristics by increasing cross-sectional area.
Comparison of Two Protein Extraction Methods for Tea Residues
Authors: Chen Xuan , Luo Hong Yu , Yu Jun , Yue Peng Xiang , Zhou Lin , Ren Yan , Wang Yu Hua , Fang Wan Ping , Li Xing Hui
Published: November 2011

Alcohol-alkali method and base digestion method were investigated to extract proteins from tea residues, respectively. According to single factorial experiments, results showed that the optimal extraction technology of alcohol-alkali method were pH 12, temperature of 80 °C, ethanol concentration of 60%, liquid-solid ratio of 40, 60 min, and the protein extraction rate reached 15.0%. And the optimal extract conditions of base digestion were pH 12, temperature of 80 °C, liquid-solid ratio of 50, 80 min, which made the protein yield reached 31.5%. Furthermore, alcohol-alkali method was more beneficial to protein extraction from tea residues under lower temperature and weak alkali condition (40-60 °C, pH 8-10). While base digestion had higher extraction yield under high temperature and strong alkali condition (60-80 °C, pH 11-12).
Patient-Specific Finite Element Model of a Spinal Tumor for Thermal Ablation
Authors: Ding Jin Li , Nan Qun , Liu You Jun
Published: November 2011

Objective: The purpose of this research is to establish a patient-specific finite element model of a spinal tumor and provide a preparation for the later numerical simulations. Method: Two steps, including three-dimensional reconstruction of the spinal tumor and its associated tissues, grid generations, are carried out for the establishment of the finite element model. Results: A patient-specific finite element model including a spinal tumor and its associated tissues is established. Conclusion: Patient-specific finite element model is a preparation for the surgical planning on thermal ablation, and the later numerical simulations will provide beneficial tutorials for surgeons.
Study on Combustor Outlet Temperature Field of Gas Turbine
Authors: Liu Kai , Xu Li
Published: November 2011

Experimental study on combustor outlet temperature field of heavy-duty gas turbine had been finished on high-pressure test system. Experimental results indicate: The OTDF is sensitive to diameter of dilution holes, and the RTDF is sensitive to location of dilution holes. The test results have important guiding significance and reference value to design, commission and working about the similar combustor.
Chemical Constituent and Antimicrobial Activity of Essential Oil from Fragrant Loquat and Common Loquat
Authors: Hong Yan Ping , Lin Biao Sheng , Ca Hong Yun , Lin Shun Quan
Published: November 2011

The chemical components of fragrant loquat and common loquat extracted by petroleum ether had been investigated using capillary GC-MS. 109 constituents were identified and the relative percentages of the constituents were determined. The highest content of chemical constituents was phytol. The antimicrobial activity on seven test organisms of essential oil from fragrant loquat and common loquat leaf extract were detected, the results indicated that these extracts had inhibitory effects on Canidia Albicans and Trichoderma spp., but not on bacteria.
Effects of AOC and Phosphorus on Bacterial Growth under Oligotrophic Condition (1)
Authors: Jiang Deng Ling , Ni Guo Wei , Zhang Yu Min
Published: November 2011

The effects of phosphorus and organic carbon on bacterial growth were investigated in the laboratory. The bacteria sampled from the drinking water network of Tianjin were inoculated into water samples with different content of phosphorus (0～15µg PO43--P/L) and assimilable organic carbon (10～200µgAOC/L). The inoculated water samples were incubated at 20°C. Bacterial growth was monitored in every 2 days in the beginning of cultivation and in every 4 days or more in the later of the cultivation. Results showed that Phosphorus had obvious promotion on bacterial growth, which included shortening the lag phase evidently, increasing the growth rate and the maximum cell count in stationary phase. Carbon can only increase bacterial number. Under oligotrophic condition，when ratio of AOC: P in nutrients of water was more than 100:5, phosphorus was the limiting factor of bacterial growth. The bacterial yield factors against phosphorus and AOC were 1.1×109CFU/µgP and 9.0×107CFU/µgAOC respectively. Phosphorus was more sensitive than AOC. When the phosphorus concentration was less than 0.7µg/L in water samples, it was very difficult for bacteria to obtain phosphorus, and then growth of bacteria was very slowly or in lag phase in the first nine days of incubation time. In drinking water with low concentration of phosphorus (<0.7µg/L) and disinfectants, bacterial regrowth may be controlled. The paper will be Narrated in two parts, “Effects of AOC and Phosphorus on Bacterial Growth under Oligotrophic Condition (1)” and “Effects of AOC and Phosphorus on Bacterial Growth under Oligotrophic Condition (2)”.
Numerical Simulation of Flow Field around Amphibious Vehicle Based on CFD
Authors: Wang Tao , Sun Wei , Yao Xin Min
Published: November 2011

Flow field information is very important to study hydro-performance of amphibious vehicle. However, it is difficult and expensive to measure it. To overcome the problem, CFD was used to acquire the information. The Reynolds Average Navier-Stokes equation was taken as basic mathematical model to describe flow field. Flow field region was discretized by hybrid mesh and governing equations were discretized by Finite Volume Method. Second order upwind scheme was used for spatial discretization and Euler scheme was used for temporal discretization. Result indicates that simulated flow field is consistent with experimental flow field on shape and hydrodynamic characteristic. Resistance accuracy is nearly 12%. It can be concluded that the method based on CFD is feasible to simulate the flow field around amphibious vehicle.
Influence of Impeller Design on Hemolysis of an Axial Blood Pump
Authors: Liu Lei , Wang Fang Qun , Wu Qin Lin , Wu Wen Jue , Qian Kun Xi , Ji Jing Hua , Zhao Wen Xiang , He Wei Xing , Li Tian Bo
Published: November 2011

Compared to centrifugal blood pumps, the high rotating speed of axial blood pumps lead to blood damage more easily. In order to improve blood compatibility of the axial blood pump developed by the authors, traditional method and three-dimensional streamlined method are used for axial impeller design, and rapid prototyping with ABS organic materials are adopted. Finally, hydraulic experiments and hemolysis tests have been conducted. The results reveal that the impeller design and the design parameters (diameter and length) affect the hydraulic performance and hemolysis of the axial pump obviously. The hemolysis index in axial flow impeller pump using traditional method is 0.12, while the minimum value of hemolysis index in the streamlined axial blood pump is 0.06, below the permitted hemolysis value of 0.1.
Nalidixic Acid Resistance and Clonal Expansion of Salmonella enterica Serotype Paratyphi a Isolates in Yuxi City, China
Authors: Yao Ying Bo , Wang Shu Kun , Chu Cong Jia , Kan Biao
Published: November 2011

The aim of our study was to understand the nalidixic acid resistance and clonal expansion of Salmonella enterica serotype Paratyphi A (SPA) recovered from patients with paratyphoid fever A in Yuxi City from 1999 to 2008. A typing method is needed to determine the epidemic clones of the isolates. Antimicrobial susceptibility testing was performed with 4 060 SPA isolates. 186 isolates were typed by pulsed-field gel electrophoresis (PFGE) with SpeI, and the MICs for nalidixic acid, ciprofloxacin, levofloxacin, ofloxacin, norfloxacin, and gatifloxacin were determined. The incidence of resistance to nalidixic acid of the isolates increased from 12.5% in 1999, 82.2% in 2000, 93.0% in 2001, to100% in 2008. Nalidixic acid-susceptible (NAS) isolates predominated in 1999 but was replaced by nalidixic acid-resistant (NAR) isolates after 2000. The frequencies of intermediary and susceptibility (Kirby-Bauer disc diffusion technique) to ciprofloxacin were 17.0% and 83.0% before 2005, 65.3% and 34.7% in 2008, respectively. A group of 166 NAR and 20 NAS isolates of SPA were randomly selected. SpeI digestion of 186 isolates gave nine different PFGE patterns with predominance of the SpeI01 and SpeI02 epidemic patterns. All NAR isolates studied had a reduced susceptibility to fluoroquinolone, the MICs were higher than that for 20 NAS isolates.We validate the use of the nalidixic acid screening test in the detection of decreased fluoroquinolone susceptibility in SPA. PFGE patterns SpeI01 and SpeI02, the main clones of the epidemics, are highly prevalent and NAR isolates in Yuxi. Recommendation for the emergency treatments of outbreaks and epidemics caused by a fully fluoroquinolone-resistant strain can be made. PFGE with SpeI is a useful technique to differentiate SPA.
Radiological Abnormalities and Clinical Characteristics for Children with Kashin-Beck Disease in Tibet
Authors: Zhang Min , Li Wen Hua , Liu Zhong
Published: November 2011

A radiological study and clinical characteristics in Kashin-Beck Disease (KBD) was undertaken on the appendicular skeleton in 213 patients with KBD in Tibet , in 134 healthy subjects living in an endemic area and in 61 healthy subjects living in a non-endemic area. Eight clinical symptoms and radiological signs of different joints in patients with Kashin-Beck disease (KBD) were studied in all cases. Arthritic pain in ankles and knee joints was the most common symptom in the early and advanced KBD children groups (1.6%,18.9%) and was significantly higher than in the in the other groups (P<0.05). Morning stiffness was observed in the all groups. Abnormal radiological changes of the finger phalanges were present in a high percentage of patients (72.9%, 86.7%) in the KBD group but that this did not occur in the healthy group. It is suggested that finger phalanges of X-rays and some clinical symptoms might be a specific criterion for diagnosing KBD.
The Blood Lead Level and Fresh Blood Quick Native Immune Reaction
Authors: Li Shi Guang , Fu Kui , Kong Qing Hao , Wu Xian Guo
Published: November 2011

Although we have gained much information about lead-induced organ damage, the effect of blood lead level on fresh blood quick native immune reaction on cancer cells is yet to be determined. The aim of study is evaluating the significance of blood level, as an indicator for environmental lead, and fresh blood quick native immune reaction on cancer cells as an effect indicator, to determinate the correlation between the content of blood lead and quick native immune reaction on cancer. The 120 children from area to exposure environmental lead were recruited into the study using cancer cells adding in fresh anti-coagulate blood to incubation at 37°C for 30 minutes and study of blood lead level using graphite stove atom absorption spectrophotometer, with blood lead level of 0.48μmol/L as a cut off value. blood lead level and fresh blood quick native immune reaction on cancer cells expression were measured with graphite furnace atomic absorption spectroscopy and using cancer cells adding in fresh anti-coagulate blood to incubation at 37°C for 30 minutes respectively. Student t test was used in data analysis, and correlation analysis was used to assess the correlation between blood lead level and expression of cancer cells adding in fresh anti-coagulate. Date from all 120 children was used for data analysis. Expression of TRR and TLR were lower in Group 1(lead level ≥0.48μmol/L) than Group 3(lead level 0.24μmol/L)(t=3.48, 2.32,P<0.01). When the blood lead level was ≥0.48μmol/L, the blood lead level showed significant inverse correlation with TRR and TLR(r=-0.703,-0.606 P<0.01). The result revealed the level of fresh blood quick native immune reaction on cancer cells was a significant difference between groups of high and low blood lead levels. There was correlation in the level of blood lead and fresh blood quick native immune reaction on cancer cells. The result suggested that the high blood lead level may be regarded as an adverse effect on children’s immune function especially on TRR.TLR percentage when exposed environmental lead.
Therapeutic Efficacy of Hyperbaric Oxygen on the Severe Acute Mountain Sickness Complicated with MODS
Authors: Zhou Qi Quan , Zhang Xue Feng , Ciwang Ren Zeng , Zhou Qiang , Fan Yong
Published: November 2011

Objective: To observe the treatment effects of hyperbaric oxygen on severe acute mountain sickness (ASHS) integrated with multiple organ dysfunction syndromes (MODS). Methods: 2006-2010 admitted to two hospitals in the Tibetan Plateau, 66 cases of patients who got the severe acute mountain sickness complicated by MODS were divided into two groups, 28 cases in the conventional therapy group, 38 cases in hyperbaric oxygen treatment therapy group, oxygen therapy, the conventional therapy concluded oxygen therapy, the treatment of primary disease and enhance the support for treatment of metabolic; hyperbaric oxygen group (was) on the basis of conventional therapy and hyperbaric oxygen therapy was used, the clinical effect of those two groups were compared with; with measured the before and after treatment blood levels of cytokines, to investigate the therapeutic mechanism of hyperbaric oxygen therapy. Results: The efficacy of hyperbaric oxygen treatment group and the treatment time are better than the conventional treatment group, hyperbaric oxygen treatment significantly reduced TNF, IL-6, IL-8 levels, and there is a significant difference between before and after treatment. Conclusion: the method of Hyperbaric oxygen for acute high altitude mountain disease complicated with MODS is reliable and had notable curative effect.
Analysis of Volatile Flavor Compounds in Huizhou Preserved Vegetable by GC-MS
Authors: Liu Yu Ping , Miao Zhi Wei , Yang Jun Kai , Guan Wei , Sun Bao Guo
Published: November 2011

The volatile flavor compounds of Huizhou preserved vegetable were extracted by hydrodistillation (HD) and simultaneous distillation-extraction (SDE). The essential oils obtained were analyzed by gas chromatography-mass spectrometry, accompanying by comparison of the retention time of authentic samples and by calculation of retention index about the separated constituents. 50 volatile flavor compounds were identified in the essential oils of Huizhou preserved vegetable obtained by HD and SDE in all. 41 compounds were identified in the essential oil from HD and 36 compounds identified in the essential oil from SDE. The constituents which are very important to the odor of Huizhou preserved vegetable include 3-hydroxy-2-butanone, dimethyl disulfide, hexanal, furfural, 2-furanmethanol, 2-methylbutanoic acid, benzeneacetaldehyde, phenylethyl alcohol, 5-ethyldihydro-2(3H)-furanone, 5-pentyl-dihydro-2(3H)-furanone, etc. The exclusive compounds in the essential oil gained by HD consist of hexanol, heptanol, 1-(2-furanyl)-ethanone, 5-methyl-dihydro-2(3H)-furanone, benzaldehyde, phenol, benzyl alcohol, methyl benzoate, ethyl benzoate. The exclusive compounds obtained by SDE are 3-hydroxy-2-butanone, dimethyl trisulfide,trans-2-(2-pentenyl)-furan, camphor, vanillin, etc. The differences result in the two essential oils with a few distinctions on aroma characteristics.
Cryoprotective Effect of Sericin Enzymatic Peptides on the Freeze-Induced Denaturation of Grass Carp Surimi
Authors: Wu Jin Hong , Wang Shao Yun , Wu Yan , Wang Zheng Wu
Published: November 2011

In this study, cryoprotective effects of sericin enzymatic peptides (SEP) on the freeze-induced denaturation of grass carp surimi were evaluated on the basis of sulfhydryl content and surface hydrophobicity of actomyosin, as well as the SDS-PAGE pattern of myosin heavy chain (MHC) of myofibrillar proteins. Results show that SEP, containing a high polar amino acid content and abundant in amino acids with hydroxyl-containing side chain (Ser and Thr), was effective in preventing the decrease of SH content, slowing down the exposure of buried hydrophobic residues on the protein surface, and retarding the degradation of MHC in a non-linear dosage-dependent way. These findings suggest that SEP obtained in our study appear to be a promising cryoprotectant applied in the frozon storage of surimi.
Optimization of DPPH Radical Scavenging Activity of Exopolysaccharides from Marine P. chrysogenum HGQ6 in Submerged Fermentation Using Response Surface Methodology
Authors: Guo Gan Lin , Guo Lei
Published: November 2011

The objectives of this study were to investigate the effect of fermentation medium on the DPPH radical scavenging activity of exopolysaccharides from marine Penicillium chrysogenum HGQ6 by response surface methodology (RSM). A two-level fractional factorial design was used to evaluate the effect of different components of the medium. Maltose, FeSO4, and K2HPO4 were important factors significantly affecting DPPH radical scavenging activity. These selected variables were subsequently optimized using a Box-Behnken design, and response surface analysis. The optimal medium compositions were (% w/v): maltose 2.71, FeSO4 0.0016, K2HPO4 0.1, and KNO3 1.0. Under these optimal conditions, the DPPH radical scavenging rate achieved 34.0%, which agreed with the predicted values.
Research on Quick Freezing Technology of Sword Bean (Canavalia gladiate)
Authors: Xu Juan , Li Qing Qing , Zhou Chen Wei , Wang Rui Zhi , Du Shan Shan , Yang Lu , Ruan Hui , He Guo Qing
Published: November 2011

Freezing technology has an important impact on the quality of quick frozen vegetables. In this study, followed blanching at 96.5 °C for 1.03 min, the effects of quick freezing of sword bean (Canavalia gladiate) on its quality were studied to optimize the quick freezing procedure. Electron microscope scanning was used to observe the microstructure, and maximum compressive strength and contents of vitamin C and chlorophyll were detected as well after quick freezing. The results showed that it was the optimized procedure to quick freeze sword bean was at-40 °C for 6.3 min, by which sword bean kept the best quality close to its fresh counterpart.
Analysis of CPn0308 Immunogenicity in the Infected Patients with CPn
Authors: Li Ping , Jia Xiao Hui , Zhou Yan , Han Xiao Yan , Tang Yu Hong , Li Xiao Jun , Jia Tian Jun
Published: November 2011

Objectives To analyze CPn0308 immunogenicity in the CPn infected patients with ICVD. Methods ①Clinical blood samples and separate plasma from blood and extract the DNA from PBMC were collected. ②The CPn IgG and CPn IgM were detected by using CPn specified diagnose kit. ③CPn DNA from PBMC was assayed by using PCR.④Imunogenicity of the endogenous CPn0308 was analyzed by Western Blotting. Results①Among the 70 patients with ICVD, the positive rate of CPn IgG was 51.43%, and it was higher than that of control; The positive rate of CPn IgM was 2.86%, and that of control was 8.47%. ②The positive rate of CPn DNA in PBMC from patients with ICVD was 81.08%，and it was higher than that of control. ③After plasma samples were diluted as 1:500, the antibodies to endogenous CPn0308 were still detected by using Western Blotting. The reaction was blocked after the plasma was pre-absorbed with GST-CPn0308 beads ahead, but not pre-absorbed with GST-CPn0186 beads. Conclusion ①There is an increase in the positive rate of CPn IgG in the patients with ICVD. ②The positive rate of CPn DNA in PBMC from the patients with ICVD is higher than that of the control. The positive rate for CPn by PCR is higher than that of EIA, and CPn DNA detection is a more sensitive method. ③The studies preliminarily demonstrate that CPn0308 has immunogenicity in the individual infected with CPn.
Dynamic Analysis of Giant Magnetostrictive Actuator with Temperature and ΔE Effect Accounted
Authors: Yuan Hui Qun , Wu Wen Bo , Li Dong , Li Ying
Published: November 2011

Considering temperature variation and ΔE effect, the dynamic model of giant magnetostrictive actuator is established, meanwhile dynamic response of giant magnetostrictive actuator and relation between magnetic field and magnetization are discussed. The simulation indicates that the relation between magnetic field and magnetization is nolinear, and a loop appears. With the amplitude of magnetization increasing, nonlinearity and loop are more obvious, and the amplitude of response will increase. Under specific amplitude of magnetization, higher temperature will get larger amplitude of magnetic field. Compare above model with the model that ignored effect, it shows that the difference between their results decrease with the amplitude of magnetization increasing.
A Mathematical Model for Frost Formation on Ground Aircraft
Authors: Wang Li Wen , Xu Dan Dan , Xing Zhi Wei
Published: November 2011

A mathematical model is developed to describe frost formation on ground aircraft. The mathematical model was based on frost formation physics together with the mass and energy balance equation developed by Mason. It can be used to forecast the frost formation on ground aircraft. Particular attention is paid to the study of the effects of the important factors, such as surface temperature, atmospheric temperature and relative humidity on the frost growth rate over ground aircraft.
Design and Implementation of Modular FPGA-Based Multiple-Axis Motion Controller for CNC
Authors: Ling X.G. , Li Qing , Ding Yan Yu , Tang Zhi Yuan , Ding Y.Y. , Xun Jing Bin
Published: November 2011

In this paper, modular design of multiple-axis motion controller for CNC using field programmable gate array (FPGA) technology is studied. The complete control system is implemented by dividing system functions into reconfigurable modules, which have been designed and implemented respectively. The timing simulations have been made to validate the feasibility for the modules. As a result, an incorporated experiment was made to check the entire performance of the controller.
Extraction of Frequency-Variable Characteristics and Analysis of Modulation Mechanism under Periodic Excitation
Authors: Wang Xin Qing , Zhao Yang , Liang Sheng , Qian Shu Hua
Published: November 2011

Free vibration of sealed hydraulic cylinder under periodic excitation has remarkable unstationary characteristics, e.g. quick change, wide frequency range and complex modulation. Combining with wavelet transform, Wigner-Ville distribution and Hilbert-Hang transform, the pressure signal of the hydraulic cylinder is decomposed, the free vibration component is extracted and re-composed, the frequency modulation characteristic is extracted and identified, and the modulation mechanism is discussed. It is demonstrated by comparison that HHT theory is effective for feature extraction and modulation analysis.
Finite Element Simulation of Extremely High Speed Machining of Ti6Al4V Alloy
Authors: Tan Yang , Chi Yi Lin , Huang Ya Yu , Yao Ting Qiang
Published: November 2011

The finite element modeling and simulation of extremely high speed machining of Ti6Al4V alloy are presented in the paper. The Johnson-Cook’s constitutive model is used to describe the material behavior. The Johnson-Cook damage initiation criterion is used to predict the onset of damage due to void nucleation in ductile fracture. A damage evaluation law based on plastic strain energy and a fracture criterion combining the effect of different fracture mechanisms are proposed to model the progressive damage and fracture, respectively. Simulation results show that the predicted chip morphology agrees well with the experimental one. The distribution of temperature and specific cutting force are discussed later.
Interior Acoustic Field Analysis of Hydraulic Excavator’s Cabin Based on Bem
Authors: Wang Yuan , Zhang Jian Run , Liu Xiao Bo , Le Vanquynh
Published: November 2011

Structure finite element model of excavator’s cabin is built, and the displacement response of cabin under the external force excitation is analyzed between 20Hz and 200Hz. In the analysis of acoustic characteristic of cabin, the boundary element model of the cabin internal acoustic cavity including the seat is created firstly. Where the result of forced response of the cabin’s structure is mapped to the boundary element model of the sound field inside the cavity as boundary condition, and the distribution of internal acoustic field is calculated and sound pressure response at the driver’s right ear is obtained. And then, acoustic boundary element grids is divided into different sections according to the corresponding structure section of the cabin to evaluate the contribution of sound pressure level at diver’s right ear from each part of cabin.
Machining Theory of Forming Complex Inner Helicoid and Numerical Algorithm to Design Contour of the Disc-Mill Cuter
Authors: Wang Ke , Wang Shu Qiang , Sun Xing Wei , Liu Guo Dong
Published: November 2011

The inner helicoid of the PDM’s stator is a kind of typical inner surface that is complex and tenuous. This paper studies the theory to form the inner helicoid in the screw stator which has a large lead and whose cross-section is composed by convex and concave curves using disc milling method. According to the varieties of the curve types of workpiece’s cross-section, a numerical method was proposed to calculate the theoretical contour shape of the disc milling cutter using coordinates of the fewer points on the workpiece’s cross-section. The manufacturing test confirmed the correctness of the design algorithm of the cutter’s profile and feasibility of this milling forming method.
Numerical Study on Structural Improvement of the Grill Fixed at the Outlet of the Air Conditioner Outdoor Unit
Authors: Liu Ying , Wu C.J.
Published: November 2011

This paper presents the techniques to numerically simulate the inner flow field of the air conditioner outdoor unit with Fluent. The results are verified experimentally and proved to be mesh-independent. The possibility of improvement to increase the flow rate by modifying the grill’s structural parameters is shown through analyzing the numerical results. The gill’s structure is improved using the flow field information got from numerical simulation and the improvement helps to increase flow rate by 4.1% and reduces the turbulent intensity near the grill significantly.
Optimization of Milling Parameters Based on Genetic Algorithm
Authors: Li Qing , Wang Run , Liu Q.J. , Wu Rong Zong , Shao M.K. , Liao C.J.
Published: November 2011

This paper presents a hierarchical genetic algorithm for interactive change search domain, using the search field continuously to shrink toward the optimal point, and also to optimize the multi-layer at the same time, conducting the interaction of individual between the layers. Individuals with the fitness value greater than zero are filtered out gradually as the most optimized cutting parameters. This method has greatly increased the time and accuracy of parameter optimization.
Experimental and Numerical Analysis for Two Kinds of Impact Vibration of Gear
Authors: Su Lin Yu , Sun Yi Qiang , Wen Jian Ming
Published: November 2011

In this paper, there are two kinds of impact vibration models: rigid impact model and elastic model. The dynamic responses of the two kinds of gear impact models are compared by experimental and numerical analysis. Firstly, establish the motion equations of the two models. Secondly, verify the correctness of the mechanical models through experimental analysis. Comparing the results of the numerical and experimental analysis, we can find that the intensity noise of gear vibration is reduced by the elastic boundary. Finally, the dynamic bifurcation characteristic of dimensionless excitations magnitude and backlash will be analyzed as well.
Research on Post Processing of 5-Axis Linkage Machines
Authors: Shao M.K. , Wang Z. , Zhi Jing Zhang , Wu Rong Zong , Wang Run
Published: November 2011

This article introduces the main task and trend of post processing of 5-linkage CNC machine. The kinematics model of 5-axis linkage CNC machine with two rotary tables was established by using the theory of mechanism and homogeneous coordinate transformation. The distribution of linear coordinate transformation and the rotate angle of machine tools were deduced by analyzing the kinematics model. Referencing above formulae, the machine’s post processing program was compiled in SOLIDCAM according to specific machine’s structure. The NC code of impeller was generated by it, and simulated it in VERICUT. The program has past the verification on TDNC-W200. The trend of post processing was got after analyzing the problem of it at last.
Research on Power Flow Transmitted through Rolling Bearing in the Gear Shaft-Plate Coupled Structure
Authors: Zhang Xiu Fang , Huo Rui , Zhou Yi Qi , Zhou Zhen
Published: November 2011

A dynamical model of a typical composite structure of plate-rolling bearing-gear shaft- rolling bearing-plate was developed, for the analysis of vibration transmission in gearbox systems. Based on the principle of mobility, a modal solution of the vibratory power flow transmitted to the plate through rolling bearings was derived. And by applying the SEA theory, a method was proposed to estimate the coupling loss factor between the plate and the finite shaft supported by rolling bearings. The SEA result was compared with the modal solution, and the properties and influencing factors of vibratory energy transmitted through rolling bearings were analyzed furtherly.
Research on the Post-Processing Algorithm about Five-Axis High-Speed Machine Center
Authors: Zhao Wei , Hadush Tedros Alem , He Qiong Yi
Published: November 2011

Research on the post-processing algorithm with the DMC75VLinear 5-axis machining center and Heidenhain iTNC530 numerical control system. The formulae about angles B and C are proposed combined with the instruction of M128.The NC codes gotten from this method had been proved in the DMC75VLinea machine, so the post-processing algorithm is tested correctly and reliably.
Resin Concrete Specimens Attenuation Characteristics Research
Authors: Ding Hong Gang , Weng Ze Yu , You Hong Wu , Lu Bo , Tang Xue Zhe
Published: November 2011

This paper introduces a method of manufacturing process of resin concrete, made three tubular cast-iron specimens filled with resin concrete. This paper detected the amplitude-frequency response curve of specimens in experimental method, and calculated the damping ratio of specimens through half power bandwidth method. The damping ratio of specimens is compared. It provided a good reference for the design of the machine tool on the dynamic characteristics.
SR Recovery Methodology Based on the Signal Classification
Authors: Zhang Pan , Dong Jing Chuan , Wang Tai Yong , Wan Jian , Hao Yan
Published: November 2011

A method to recover the distorted signal in the bistable stochatic resonance(SR) system is proposed.This paper investigates the movement track of a particle in the bistable system and the suggested recovery system. In terms of the spectrum feature, we define the series of methods as the SR recovery methodology based on the signal classification. The signal is classified as the sinusoid-alike signal or the pulse-alike signal. To the sinusoid-alike signal, a cascaded-bistable system was introduced to genrate the second tuning for the residual noise and the recovery system with the parametric tuning was applied to restore the output waveform;For the pulse-alike signal ,a mono-stable system was introduced for the residual noise and the recovery system with the parametric fixed was applied to restore the output waveform. The engineering experiments has presented that it can recover the weak information submerged in noise effectively.
Strength Optimization Design of Box-Shape Arms of a Scissor Lift Mechanism with Single Hydraulic Cylinder
Authors: Zhang Wei , Wang Xin Xu , Wang Li Wen
Published: November 2011

One widely-used scissor lift mechanism with the input mode of single hydraulic cylinder is researched. A unified accurate mechanics model of mechanism arms is constructed. By establishing statics, interior forces and stress formula, the general strength optimization design method of arms is explored. Through analysis of an existed sample, validity of the proposed method is verified in contrast with experiment results. Variation law of mechanical parameters within lifting process is uncovered by modeling analysis of the sample mechanism, which also indicated the necessacity of arms optimization. Finally, a dimension optimization of box arms of proposed mechanism is fulfilled with concept of constant strength to prepare for the coming finite element simulation, experiment research.
Study on Post-Processing of Five-Axis Cnc Machining
Authors: Zhi Jing Zhang , Ren Cheng Zu , Dong Jing Chuan
Published: November 2011

According to the feature of five-axis CNC machine tools’structure, do researches on post-process technique. By means of analysis of the kinetic model of five-axis CNC machine tools, Position and orientation of the tool in the workpiece coordinate system transforms to that of the machine coordinate system. Besides, Because of the rotation，Five-axises maching will produce the non-linear error．This article provides an easy algorithm to find the maximum non-linear error. Finally, an impeller, for example, simulates in the computer and machine by a 5-axis machine tool.
Application of Growth Production Design DNA Calculation Inference on the Building Process of Packing Product Line Virtual Prototype
Authors: Shi Li Wen , Xie Qing Sen , Tian Ran
Published: November 2011

The quick design and manufacture efficiency of the new production design is a significant issue faced by modern enterprises, the key of which is that how to assure the efficient collection and reuse and benign accumulation of enterprise production knowledge base. To create a series of design scheme and keep the succession of brand type, and achieve the continuation of the offspring product characteristics. In this passage, the defect of the related technology is deeply analyzed, and the production design DNA calculation inference method is applied into packing manufacture line (partly unit machine) virtual prototype building process. And the quick creation and design criteria of packing production line can be achieved, which proves the semantic theory of growth production design based on genetic algorithm.
Test Methods for Durability of Electric Nail Gun
Authors: Ding Hong Gang , Zheng Yan Qin , Song Lin Jun , Weng Ze Yu
Published: November 2011

Durability is very important to evaluate the performance of electric nail gun. This paper has studied the working principle of the electric nail gun; and presents a method for evaluating parameters of the electric nail gun durable test, and the general procedures for durability test of electric nail gun; and developed the devices of durability test of electric nail gun on special model.
A Theoretical Model for Calculating Vibration Characteristics of A Kind of Driver Seat with Air Spring and MR Damper
Authors: Zhu Xing Xing , Zhu Si Hong
Published: November 2011

In order to further reduce the vibration transmitted from vehicle to driver, a new model of driver scissors linkage seat suspension was put forward, in which an air spring with auxiliary chamber and a MR damper are between the face and floor of the seat. The motion differential equation of this seat suspension system was established and the theoretical computing formulation of it’s equivalent vertical stiffness, equivalent damping coefficient, natural frequency and damping rate were deduced. Besides, taking HY-Z04 scissors linkage seat, SK37-6 air spring of ContiTech and RD-1005-3 MR damper of LORD as an example, the equivalent stiffness and damping coefficient in different conditions of the air spring pressure, the sprung mass, the orifice diameter and MR damping were computed and analyzed. The study results show that the air spring pressure, the sprung mass, the orifice diameter and MR damping all have obvious influence on the equivalent stiffness and damping coefficient, so the seat comfort can be improved by changing the air spring pressure, the orifice diameter and MR damping according to driver’s weight and road condition.
Non-Linear Dynamic Stability of Shallow Reticulated Spherical Shells
Authors: Han Ming Jun , Li You Tang , Qiu Ping , Wang Xin Zhi
Published: November 2011

The nonlinear dynamical equations are established by using the method of quasi-shells for three-dimensional shallow spherical shells with circular bottom. Displacement mode that meets the boundary conditions of fixed edges is given by using the method of the separate variable, A nonlinear forced vibration equation containing the second and the third order is derived by using the method of Galerkin. The stability of the equilibrium point is studied by using the Floquet exponent.
Effect of Water Stress Induced by PEG on Growth and Quality of Bunching Onion
Authors: Dong De Zhong , Liu Hou Cheng , Song Shi Wei , Sun Guang Wen , Chen Ri Yuan
Published: November 2011

The effect of water stress on growth and quality of bunching onion（Allium fistulosum L. var. caespitosum Makino）was studied in hydroponics by PEG treatments (10%, 15%, 20%). The results showed that the growth of bunching onion was significantly affected by water stress induced by PEG. Plant height, pseudo-stem weight, total plant weight decreased with PEG concentration increased, the inhibitions in 10% PEG and 20% PEG were greater than in 15% PEG. The root/shoot ratio increased in PEG treatments. Concentrations of allicin and pyruvic acid significantly increased at 10, 17 days after PEG treatments. With PEG concentration increased, concentrations of soluble protein increased.
Investigation on Stress Field near Crack-Tip of Mode I in Shape Memory Alloy
Authors: Zhou Bo , Guo Xiao Gang , Hou Gang Ling , Li Xu Kun
Published: November 2011

In this paper a phase transformation equation is supposed to describe the phase transformation behaviors of the shape memory alloy (SMA) under complex stress state. The stress field near crack-tip of mode I in SMA at various temperatures is investigated based on the supposed phase transformation equation and linear elastic fracture mechanics. Results show both the martensite region and the mixed region of martensite and austenite near the crack-tip become larger with the decrease of temperature. The fracture mechanics behaviors of SMA are much influenced by the temperature.
Study on the Advanced Treatment Secondary Effluent of WWTPs by Coagulation
Authors: Liu Yue , Li Fu Xiang , Zhang Chun Peng
Published: November 2011

The secondary effluent of WWTPs can be treated by the coagulation advancedly. The laboratory results showed that, PFS and PAC had lower efficient for the treatment of pollutants, and the effluent can not meet the requirements, so they were not s uitable as the coagulant. The PSFA, produced by the laboratory, had a higher removal rate of pollutants, and the quality of effluent can meet the relevant requirements of the standards, so it can be used as the coagulant of advanced treatment. The results of the experiment showed that the optimal dosage of PSFA was 20mg/L, and the COD, SS, turbidity, chromaticity, and TP of effluent were 9.5mg/L, 4.9mg/L, 2.7NTU, 10times and 0.15mg/L respectively.
Interface Fracture Criterion Based on Molecular Dynamics Simulation
Authors: Yang Zhen
Published: November 2011

Fracture of coating materials often occurs at or near the interface, while the mechanism and criterion of interface fracture are not clear yet. A molecular dynamics simulation method was introduced to simulate the interface crack initiation, and the relationship between the interface stress and the interface fracture was found. Although a simplified model was applied, the results still showed some intrinsic features that are useful to study the process of interface fracture. At last, an interface fracture criterion was proposed.
The Improved Design of Some Shrunk Super High Pressure Cylinder Based on Equal Strength Theory
Authors: Zhang Yu Xian , Wang Li Fu , Yao Fang
Published: November 2011

According to the equation of shrunk interface pressure and the condition of diametrical ratio based on the theory of equal strength, it is found that the diametrical ratio isn’t true of the condition of diametrical ratio and the distribution of stress isn’t very equality through analyzing and calculating the diametrical ratio and stress to a super high pressure cylinder. Then aim at the problems existed in the super high pressure cylinder, it is taken the improved design. The super high pressure cylinder has much better than original one in distributing of stress. It is shown that the improved design project has a better technical result.