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Based on the dynamic analysis of ANSYS for the intense state of cutlery and ice, the device can be judged whether it can successfully finish the ice and snow removing job. And the process of straight cutting tool of the same height, width and length with the bending one removing the same ice is analyzed using ANSYS under the same the situation. So the stress distribution diagrams were studied. Comparing the stress distribution diagrams between the cutting tools and ice and snow, some results can be gotten. In addition, the rationality of the choice of cutting tool can be proved.

In the current, Colleges students are universal love Taekwondo, it has been widely spread in the university, and some universities will Taekwondo to set for compulsory courses of sports teaching. And now the study is less for Taekwondo of foreign spread, the study of Taekwondo is also confined to the study of Taekwondo for college students’ psychological health effects research, and rarely to analysis of Taekwondo in domestic colleges are widely spread reason. This article is mainly based on this to solve this problem, analysis of Taekwondo popular reasons in collage. According to college students to conduct research and reliability validity and factor analysis, it can draw Taekwondo widespread promotion factor, which can better enhance the student body quality improvement and can rich the universities sports teaching, to achieve physical exercise and lifelong education to lay a good solid foundation.

A series of hepatic amino functional cholesterylated hepatic targeting liposome ligands L1-L6 were synthesized. Cholesterol as starting material, after esterification with p-toluenesulfonyl chloride to get cholesterol tosylate, then etherification with oligo ethylene ethanol (n=1-3) to get amino functional cholesterylated compounds T1-T3, T1-T3 were elongated by reaction with protected diethylene glycol and deprotected in acid condition to get T4-T6 . L1-L6 were mesylated and replaced by azido group, then hydrogenanted by hydrogen to get L1-L6.The target compounds affords cholesterylated hepatic targeting liposome ligands.

A carboxyl functional cholesterylated compound for hepatic targeting liposome ligand T1 was synthesized. Cholesterol as starting material, after esterification with p-toluenesulfonyl chloride to get cholesterol tosylate M4, then etherification with tetraethylene glycol to get hydroxyl functional M3, M3 react react with methanesulfonyl chloride to get M2, M2 was elongated by reaction with PEG2000 to get M1 and M1 react with succine anhydride get T1. The target compounds afford cholesterylated hepatic targeting liposome ligands.

According to the characteristics of the ore under inclined lane transportation, design a kind of system which can prevent the transport vehicle’s speed out of control. The system can according to the different load of transport vehicles and the stall speed given different braking force to expand the application range of the system and increased its practicability. This set of system automation control and flexible intercept, prevent the stalled car accidents, and eliminate potential safety problems.

The PIL which were prepared from imidazole and epichlorohydrin were used as catalysts for the conversion of cellobiose to 5-HMF. Effects of the catalyst anion, solvents, reaction temperature, and recycling time were investigated in detail. The optimum reaction conditions for conversion of cellobiose into 5-HMFcatalysed by [IMEP]BF4 were temperature 180 oC, cellobiose 0.5 g, and [IMEP]BF4 0.25 g in DMSO(30 mL). In this condition the yield of 5-HMF can reach 39.2% for 420min. The good positive correlation between the concentration of glucose and the formation rate of 5-HMF was given, and the conversion of glucose into 5-HMF is the key step of formation of 5-HMF from cellobiose. Moreover, [IMEP]BF4 has well cycle performance in the optimum reaction condition.

The poly (butylene succinate) (PBS) and 3 wt% attapulgite (ATP) reinforced PBS/ATP nanocomposites with 1,6-hexanediol were fabricated using an in situ polymerization method. The crystallization behaviors indicated that ATP had effectively acted as nucleating agent, resulting in the enhancement on the crystallization temperature. The SEM results showed a superior interfacial linkage between ATP and PBS. Also, ATP could disperse as a single fiber and embed in the polymer matrix, which resulted in the improved mechanical properties.

Due to the early years of mining makes Gob fracture zone, the deformation of rock fracture zone, and gradually developed through. Located in the mined-out area causing tension within fractured zone of discontinuous deformation region arsenal varying degrees of ground and walls to crack, great security risk to the normal operation of the arsenal caused. Project uses Sleeve Valve Pipe and Steel Pipe Micropile reinforcement scheme. This paper describes the details of the reinforcement mechanism, the construction process, technical requirements and quality assurance measures. Practice has proved that the joint reinforcement program can continue to crack the wall of effective governance to ensure the safe operation of the security arsenal.

Longmenshan earthquake fault zone has experienced several earthquakes in history, the formation is extremely broken and contains some very loose and strong water-sensitive shale formation. Due to the complexity of engineering of geological conditions, drilling accident-prone. In this paper, for example WFSD-4 well, and use of ANSYS Workbench to establish a simplified of fracture accident of WFSD-4 well drill collars, analysis stress and fatigue damage of BHA model. The results showed that the maximum stress occurs at the bottom of the drill string, the first position of fatigue failure is in the drill string at the bottom of the drill bit, the entire drill string fatigue life is 1.66 × 10e9 cycles, and through the analysis to guide the design, manufacture and use of BHA.

This paper studies the flexural fatigue performance for hose reinforcement layer fiber bundles including polyester fibers, para-aramid fiber and liquid crystal polyester fiber. Bending fatigue life and changes of three fiber bundles strength during the course of fatigue development were measured. Morphology of three fiber bundles was observed by scanning electron microscopy. From the analysis of the molecular structure of the three fibers, the Molecular chain flexibility is one of the main factors of impacting resistance to bending fatigue performance. Liquid crystal polyester fiber bundles have excellent mechanical properties and the high strength retention in bending fatigue test, which is an ideal material for the production of high-strength hose.

A mathematical model was developed to assess the economic feasibility of a biomass-based power plant in the Northeast of China. The objective of this model is to maximizes the net present value (NPV) of a biopower plant over its economic life, which subjects to the constraints of biomass availability, plant investment and operation & maintenance costs, plant capacity, transportation logistics, raw material and product pricing, financing, and business taxes. The model was applied in a biopower plant located in Wangkui County, China, which belongs to the National Bio-Energy Group Company Limited. Results showed that the maximum NPV of the Wangkui Biopower plant in the base case was approximately 117 million Yuan given the electricity sale price of 0.64 Yuan kWh-1 (or 0.75Yuan kWh-1 with tax). This study provides a reference for evaluating the economic feasibility of biopower plants based on biomass logistics networks in China.

The operation of many biomass-based power plants in China have demonstrated that biomass supply logistics system is a key part to achieve economic, stable, and safe operation for such plants. In this paper, the straw biomass supply system of a biomass-based power plant located in Wangkui County, Heilongjiang Province was analyzed, and a mathematical model was established to optimize the fuel supply system. In consideration of the current straw biomass fuel supply system in China, that is "fuel origin – purchasing station - power plant", appropriate hypothesis and simplification were made on the linear transportation model. The logistics parameters for the biopower plant were obtained through the model analysis. Sensitivity analyses were conducted to analyze the optimal delivered cost of biomass under different operation scenarios, which enhanced the reliability of the final results. The optimal model proposed in this paper can also be used as a reference for the other biopower plants in the other regions.

Speech can be broadly categorized into voiceless, voiced, and mute signal, in which voiced speech can be further classified into vowel and voiced consonant. With the ever increasing demand of the speech synthesis applications, it is urgent to develop an effective classification method to differentiate vowel and voiced consonant signal since they are two distinct components that affect the naturalness of the synthetic speech signal. State-of-the-arts algorithms for speech signal classification are effective in classifying voiceless, voiced and mute speech signal, however, not effective in further classifying the voiced signal. In view of the issue, a new algorithm for speech classification based on Gaussian Mixture Model (GMM) is proposed, which can directly classify a speech into voiceless, voiced consonant, vowel and mute signal. Specifically, a new speech feature is proposed, and the GMM is also modified for speech classification. Simulation results demonstrate that the proposed algorithm is effective even under the noisy environments.

Automatic license plate recognition system is an intelligent surveillance system in traffic management and toll. Various image restoration methods have been proposed, but they are deficient in function approximation. Neural network has its unique advantages for its large-scale nonlinear dynamic characteristic, parallelism calculation, high robustness, strong capacity of self-adaptive, self-organization and self-learning. A novel license plate preprocessing technique based on fuzzy neural network has been proposed here, which is verified to be effective by the experiments.

Computer aided design was adopted into the design process of winching drum in this paper. First, mathematical modeling was conducted to the design based on traditional means. Then the parameters of the winching drum were optimized by MATLAB. And the smallest drum was obtained under the condition of same length winching rope. In order to check the optimal design result of the strength of the drum in the bad operation environment, finite element analysis method was adopted, which simulated and verified the reliability of the winching drum.

Based on the numerical calculation of three-dimension flow field of the exhaust system, a code is developed by the reverse Monte-Carlo method (RMCM) to simulate the infrared radiation characteristics of the aeroengine exhaust system and the plume. A ray-tracing method (RTM) is introduced to seek the meshes of the flow field which the ray travels through to avoid the trouble of interpolation. The infrared radiation characteristics of a certain turbo-fan engine’s ejector nozzle in the waveband of 3-5μm is simulated at non-afterburning condition. The results of the simulation show that : (1)Because of the introduction of the secondary flow, the average temperature of the ejector nozzle’s core plume is 20K lower than the baseline one’s.(2) The infrared intensity for the ejector nozzle is most reduced relatively by 44.5% in comparison with the baseline nozzle along lateral direction.(3) The ejector nozzle has a better performance of infrared stealth.

Genetic algorithm (GA) is improved with fast non-dominated sort approach and crowded comparison operator. A new algorithm called parallel multi-objective genetic algorithm (PMGA) is developed with the support of Massage Passing Interface (MPI). Then, PMGA is combined with Artificial Neural Network (ANN) to improve the optimization efficiency. Training samples of the ANN are evaluated based on the two-dimensional Navier-Stokes equation solver of cascade. To demonstrate the feasibility of the hybrid algorithm, an optimization of a controllable diffusion cascade is performed. The optimization results show that the present method is efficient and trustiness.

The principle of geometric analysis was adopted in this paper to calculate the ultrasonic testing accuracy of log samples containing different sizes of internal decay. The relationship between the number of ultrasonic emission points and the detection accuracy of log internal decay was analyzed. And the number of emission points that can effectively test the internal decay defect was determined. Results show that when the defect area of the log is fixed, the testing accuracy can be improved as the ultrasonic emission points increase. When the diameter of the log is 30cm, and the ratio of deficiency in the cross-section of the log is between 2.7% to 44%, at least 4 emission points should be selected for the testing accuracy to reach 90%.

Based on the development of forestry machinery and the causes for tractor accident, this paper analyzed the necessity of improving the small skidding tractors. Then the automatic overload alarm and automatic anti-tipping alarm were designed through the research on overload and tipping point of small skidding tractors. The main parameters of the devices were calculated, the operational principle was described and the two wiring diagrams were given. The feasibility of these two alarm devices is proved theoretically in this paper. Two ways are provided to improve the safety of logging operations of the tractor and an effective research method for its intelligent development in China is planed.

The effects of timber production (mainly refers to cutting) on forest carbon storage can be studied from two aspects as follows:(1) calculate the original carbon storage of the forest vegetation carbon pools based on the forest survey results in the year of 2002, and then calculate carbon storage of 2006 in two cases according to the growth rate of wood. The first case is that calculate the forest carbon storage assuming the forest has not been cut. The second case is to calculate the carbon storage of the residual trees in 2006. The difference in value is the result this study needs to calculate. (2) Automatic measurement system LI-8100, commonly used for measuring carbon dioxide emission flux in soil, was adopted in this paper, and soil respiration rate of forest land in the growing season was measured according to coniferous and deciduous broadleaved mixed forest plots of different selective cutting intensity in Dongfanghong Forest Farm of Dailing Forestry Bureau of the Xiaoxing’anling Mountains. Then the effects of timber production on forest carbon storage were determined based on an overall consideration of the changes of vegetation and carbon storage of soil carbon pool.

An experiment was conducted to Korean pine specimen by ultrasonic tester. The effect of hole size and holes amount in axial direction of wood as well as the distribution of end holes on ultrasonic wave velocity were respectively studied. A comparison test was carried out between the specimens of one hole defect and no defect with different lengths. Then regression analysis of the relation between hole size and ultrasonic wave velocity was done using SPSS software. The experimental results show that the length of wood components has significant effect on ultrasonic wave velocity. The ultrasonic wave velocity has negative correlation with hole size and holes amount. End hole has no significant effect on ultrasonic wave velocity. This research will provide some theoretical basis for the detection of internal defects in wood materials, material evaluation and the evaluation of physical and mechanical properties testing.

The effect of Ce substitution at the A-site on the properties of Na0.5Bi4.5Ti4O15 (NBT)–based ceramics was systematically investigated. The substitution at A-site caused distortion of lattice and improved piezoelectric activity correspondingly. The piezoelectric coefficient d33 of the Na0.5Bi4.5-xCexTi4O15 (x=0.03) ceramic was found to be as high as 26 pC/N, together with high mechanical quality factor Q ( 2769 ), and stable piezoelectric properties, demonstrating that the Ce-modified NBT-based materials are promising candidates for high-temperature applications.

In order to carry out non-destructive testing on standing trees, explore the propagation characteristics and the influence factors of the ultrasonic wave spreading in the standing trees. Take simon poplar as the research object, Resistograph were employed to test 30 sample (simon polar) standing trees and it gave a preliminary estimate of the internal defects in the samples, and RSM-SYS5 ultrasonic device were employed to test the ultrasonic propagation velocity spreading in simon poplar standing trees, with the statistics of the ultrasonic propagation velocity spreading separately in the health trees and standing trees with defects, and did a regression analysis of the relationship between the size of the defacts and the ultrasonic propagation velocity. The results show that: 1) When the diameter of sample trees are between 30 and 55cm, the radial velocity of ultrasonic spreading in healthy simon poplar standing trees are in the range of 1029.96m/s ~ 1200m/s, all more than 1000m/s; however, when there are defects in simon poplar standing trees, the ultrasonic radial velocity are less than 1000m/s. 2) The defacts in standing trees have an significant influence on the ultrasonic radial propagation velocity spreading in simon poplar standing trees, defect size and the radial velocity is significantly negatively correlated, and the correlation coefficient R is 0.887.

Larch lumbers were tested by using modal analysis technology and Frequency response functions (FRF) were derived. Modal parameters, including first 4 intrinsic frequency and first 3 modal shape, were distinguished by single modal method. Research shows that the intrinsic frequency of hole-defect lumbers is little lower than standard lumbers’ and the change rate of frequency is becoming larger gradually with the diameter of hole-defect. However, it can not judge the position of the hole-defect by the change rate of frequency. The modal shape of the node near the hole-defect always jumps abruptly, so it can estimate the particular position of hole-defect in the lumber. The variation of modal shape is becoming larger gradually with the diameter of hole-defect. It can make qualitative and quantitative estimate to the hole-defect in the lumber by considering intrinsic frequency and modal shape together.

A new method was proposed to determine the size and location of the internal deficiency of the standing trees using the acoustic velocity of the ultrasonic, and the method was explained in specific on the process of how to put it into practice. Through the comparison of the experiment on defective Dahurian Larch between the ultrasonography and the Resistance Drilling, the results proved that the method was available and concluded the accuracy of this method when testing deficiency. Meanwhile, the average transmission velocity of the ultrasonic in Dahurian Larch was obtained through large amount of experimental data.

The crystallinity of wood is an important property of wood materials, it has an important effect on the physical, mechanical and chemical properties of cellulose fibers such as MOR, density, hardness increase, alpha-cellulose content, dimensional stability, moisture regain and dye sorption, chemical reactivity etc. The aims of this study were to investigate the ability of near infrared spectroscopy (NIR) to predict the crystallinity of white pine wood and the effect of spectra pretreatment on the prediction of crystallinity using NIR. Spectra were collected from wood powder a slowly rotating turntable and the crystallinity of wood was determined by X-ray diffractmeter (XRD) in this experiment. The results showed that NIR coupled with partial least square (PLS) method could be correlated with the crystallinity of white pine wood, and the ability of NIR prediction based on first derivative spectra was better than based on raw spectra or second derivative pretreated spectra. There was a significant correlation between NIR spectra and XRD determined crystallinity. The correlation coefficient for calibration (RC) was 0.932; the mean square error of calibration (RMSEC) was 0.022; the correlation coefficient for validation (RV) was 0.911; the mean square error of calibration (RMSEV) was 0.023. It was proved that NIR can rapidly and accurately predict white pine wood crystallinity.

This paper introduces the development of red laser positioning computer-aided-signage system. This series of laser cutting machines have red laser auxiliary positioning system, powerful cutting system, the workbench powerful software support, the use of simple, convenient and low cost, complete with diverse demand of cutting, according to relevant literatures, this kind of technology and products to domestic initiative. This product adopts mechanic-electrical comprehensive technology, can achieve the design rules for the high speed and high precision positioning for advertising and cutting, printing industry to design a digital contour cutting provides solutions, changed the traditional manual shear mode, improve the production efficiency.

The dynamic modulus of elasticity (MOE) of forty one small Acer mono clear wood specimens was tested via stress wave, ultrasonic wave, edgewise vibration and flatwise vibration method respectively in laboratory. Then the static MOE of these specimens was measured with static bending test. The correlations between dynamic and static MOE were analyzed using linear regression method, and the difference of various methods was discussed using paired t test. The results show that the dynamic MOE of wood measured by four methods described above are higher than the static MOE, but their linear correlation is significantly strong. Thus, it is feasible to estimate static MOE using these four methods. Additionally, the mean of paired difference between static MOE and dynamic MOE tested by flatwise vibration method is least, and the correlation highest. Therefore, it is better to use flatwise vibration method to estimate static MOE of wood.

To effectively and quickly estimate the dynamic modulus of elasticity (MOE) of wood, ultrasonic and vibration test techniques are employed to measure the intact and damaged wood specimens. The ultrasonic and vibration signals in time domain are obtained respectively. Then, the time of flight is received by picking up the position of ultrasonic head wave and it is used to compute the dynamic MOE of wood. Simultaneously, the frequency response functions of wood are received by analyzing the frequency domain signals transformed from time domain using Fourier formulas, and they are used to pick up the intrinsic frequencies to calculate the dynamic MOE measured by vibration test. Finally, the correlations of dynamic MOE tested by these two methods are discussed. The research results show that it is feasible to estimate the dynamic MOE of wood via ultrasonic and vibration signal processing.

Sr0.48Ba0.24Ca0.28TiO3-based varistor ceramics with an excellent capacitor-varistor multifunctional characteristics (V1mA = 11 ~ 49 ν.mm-1, α = 6.1 ~ 11.3, ε r max=3.5×105, tanδmin = 5%) were prepared using conventional solid method. The effect of oxidation temperature and time on structure and electrical properties were investigated. The results show that with increasing the oxidation temperature from 800°C to 900°C, the varistor voltage V1mA and non-linearity coefficient α defining varistor characteristics increase linearly, while the dielectric constant ε r and dielectric loss tanδ decrease linearly. There exists an optimum α value when the specimens were oxidized at 850°C for 3h. This behavior was explained through various defect reactions of dopants.