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To ensure the sustainable water development of regional agricultural and improve the use efficiency of water, it is very important to optimize the allocation of water resources. There are many uncertain factors in the process of the water resources allocation in the food production areas with the change of the system environment in China, and in the pursuit of the minimum cost, there are also many uncertain risks. Choosing the 5 important agricultural regions, i.e. Qitaihe, Jiamusi, Shuangyashan, Hegang and Jixi located on the Sanjiang Plain as the study area, by using the method of interval two-stage stochastic programming method and introducing the risk appetite, the surface water and groundwater joint scheduling is established under the condition of water resources optimal allocation, and the water deficit and the optimal configuration of water law for each administrative region are analyzed. The results show that the surface water is much deficient in Shuangyashan and Jixi during the water distribution process, where the mainly exploited is the groundwater; for Jiamusi, which is an administrative region with larger grain production area, the water demand is bigger, and the external water supply is more; for Qitaihe and Hegang where the planting areas are lesser, considering the cost of water diversion and grain yield, the less external water is needed to pilot to reduce the cost. The calculation results show that the changing rules of water deficit and the optimal allocation of water under different administrative region and different water level are as follows: Qitaihe and Jixi have small change under different water level, Jiamusi and Shuangyashan have great change under different water level, and the minimum cost of water under the optimal allocation is 736.12×108-843.40×108 yuan. At last, the paper analyzes the minimum cost of optimal allocation of water resources under different probability of water level and different risk preference scenario on Sanjiang Plain. Because under the low water level, it is easy to cause the high demand for water resource system, and an increased level of risk aversion can be instead of water cost increase, the cost of water shortage will be increased to meet the basic requirements of crops, which changes from 344.2×108-355.4×108 to 411.5×108-430.7×108 yuan; at a high level of the water, the increase of the level of risk aversion can reduce the cost which caused by the loss of oversupply, and thus reduce the total cost of water from 422.5×108-435.3×108 to 351.7×108-365.3×108 yuan; in the middle level, it is between low and high water level. This model conjoins the advantages of the interval of two-stage stochastic programming and the characteristics of the risk value model. In the joint allocation of water resources, the model comprehensively considers the cost and risk, effectively saves water cost, and enhances the ability of water resources system to avoid risk. The model makes up for the deficiency of the traditional interval two-stage stochastic programming method, introduces the risk preference of decision makers to find the minimum cost of water resources’ optimal allocation scheme under the condition of uncertainty, avoids concentrating the risk loss in a certain region, and facilitates reasonable water resource allocation for policymakers in different administrative regions on the Sanjiang Plain. The water allocation in different region and different time realizes the dynamic distribution of multi-water source irrigation system. This model can ensure the need of crop grow when the irrigation water resources are rationally configured in the growing period of the crop, and effectively avoids the waste of water resources, as well as improves the efficiency of irrigation water, which is of great significance for sustainable use of water resources. The research improves the utilization efficiency of water resources and provides the basis for the planning of regional water management, which can more truly reflect the uncertainty for optimization allocation of water resources. [ABSTRACT FROM AUTHOR]

In order to solve the problems of multi-dimensional vibration in industry and agriculture effectively, the optimization design of the 3-PRC parallel mechanism is carried out for improving its kinematic performances and mechanical properties. A classic 3-PRC parallel mechanism with 3 translational degrees of freedom (DOF) has some defects such as asymmetry, and low mobility. Therefore, for eliminating these defects, the 3-PRC parallel mechanism is upgraded into a novel 3-PRRP4R parallel mechanism by adopting some optimal measures. Firstly, change the cylindrical pair into a revolute one and apply a 4R structure which includes 4 revolute pairs in the mechanism so as to make the parallel mechanism move more smoothly. Additionally, change the arrangement form of sub-chains from square to equilateral triangle, which makes the force distributed more homogeneously on platforms. Finally, change the position relationship between the sliding pair and the revolute pair, and eliminate the unwanted additional torque. After the improvement of the mechanism, based on the screw theory, the degree of freedom and the motion form of the 3-PRRP4R parallel mechanism are analyzed. The result shows that the 3-PRRP4R parallel mechanism is still a 3-DOF translation mechanism which can be used as three-translation vibration reduction platform. Using the homogeneous coordinate transformation method, the kinematics of the 3-PRRP4R parallel mechanism is formulated. The inverse kinematics solution describes the displacement relationship between upper platform and active joints which are on the lower fixed platform. Jacobian matrix, which describes the velocity relationship between upper platform and active joints which are on lower platform, is obtained by the analysis of velocity. Through the coordinate searching method, the workspace of the 3-PRRP4R parallel mechanism is obtained, which has better symmetricity than the classic 3-PRC parallel mechanism. The comparison of the workspaces shows the 3-PRRP4R parallel mechanism is more suitable as a multi-dimensional vibration reduction mechanism. With the help of Adams software, the mechanical properties of cylindrical pair and 4R structure are analyzed, and the result proves 4R structure has better mechanical properties than cylindrical pair. The multi-dimensional vibration reduction system is established by using the 3-PRRP4R parallel mechanism as the main body and installing the spring damping between active joints and lower platform. Based on the principle of virtual work, the statics of the 3-PRRP4R parallel mechanism is analyzed. Static equilibrium equation, which describes the force relationship between upper platform and active joints, is established. Static equilibrium equation can be used to set the structure parameters of mechanism and the preload of spring at the initial time. The stiffness of parallel mechanism describes the relationship between the force on upper platform and the corresponding displacement of upper platform, and it is very complex. In order to describe the spatial distribution law of the stiffness visually and briefly, the equivalent stiffness is introduced, and its formula is derived as well by means of dividing the magnitude of the force on upper platform by the magnitude of the displacement of the upper platform. With this formula, the equivalent stiffness in any arbitrary position can be obtained. With the help of MATLAB, the obtained figures, which describe the distribution law of equivalent stiffness in some special positions, show the general distribution law of equivalent stiffness in workspace. The distribution law of equivalent stiffness can help us to make sure whether the special position is useful or not, so it is very important for the application of parallel mechanism. Therefore, the paper provides some valuable guidance for the optimization design, the dynamic analysis, the equivalent stiffness inspection of parallel mechanisms, and the application of multi-dimensional vibration reduction system. [ABSTRACT FROM AUTHOR]

Ride comfort is of great importance feature for the heavy truck, its optimization can improve the driver's driving conditions to reduce fatigue, and make the goods safer. Primary factors that can influence ride comfort are form and parameters of suspension, which are suspension stiffness, suspension damp and their combination. When the form of suspension is confirmed, more reasonable parameters can be selected by optimization method to improve ride comfort. Ride comfort optimization analysis belongs to the combinatorial optimization problem, at the same time, the nonlinear characteristics in optimization is essentially a nonlinear multimodal optimization problem. In this paper, at first, a nine degree of freedom vehicle vibration model was established; Vehicle driver seat acceleration simulation tests were conducted with different vehicle speed. Also, both time and frequency domain analysis was implemented with MATLAB software development platform. On the whole, with the increase of the speed of the vehicle, the acceleration root mean square of vehicle driver seat became larger, so the vehicle ride comfort performance reduced. Especially at low speed and high acceleration change is more obvious. But in 40~80 km/h, the acceleration change quite gentle. That means to achieve the better economy and the vehicle ride comfort performance, the vehicle speed keeping in a medium speed is better. Based on C level road and the speed of 70 km/h, with an eight by four dump truck as experimental object, the ride comforttests were conducted, moreover the test results compared with the results of simulation. The compared results showed that the simulation and the test were very close. And then, today technology was coming to a stage of intersection, infiltration, and interaction with multi subjects. More and more issues on complexity, non linearity, and system have come to us. To deal with such complexity of system, conventional techniques have become incapable, and to seek an optimization algorithm, which adapt to large scale parallel with intelligent characteristics, has been a primary research target of related subjects. The artificial fish algorithm was proposed to optimize ride comfort. The artificial fish swarm algorithm (AFSA), anew method based on animal behaviors and the typical application of behaviorism artificial intelligence, was proposed byan internal scholar in recent years. It used the operators such as prey, swarm, follow and random behavior. The algorithm parameters, such as population, step size, sense of distance, the largest try number, crowded degree coefficient and the largest number of iterations, has a great impact on the performance of the convergence. At the end, the artificial fish algorithm was used to optimize ride comfort by reasonable selection of the suspension parameters. The objective function was the acceleration root mean square of vehicle driver seat to be minimized. The decision variables were front suspension stiffness and damp. Moreover AFSA need to set up the appropriate algorithm parameters. For example, population scale, step size, sense of distance, the largest try number, crowded degree coefficient and the largest number of iterations was 100, 100, 20 000, 100, 9 and 50. Where the population scale N was called the number of possible values of suspension parameters within the value range, step size was suspension parameters increasing or decreasing the amount of each iteration, and sense of distance visual was variables scope of each iteration. Optimization results show that the acceleration root mean square average fell by 16.82%, the biggest fell by 21.24% in 60 km/h, so it effectively improves the ride comfort h performance of heavy vehicles. [ABSTRACT FROM AUTHOR]

This paper proposes a novel semi-rigid C-joint for spatial lattice structures. In order to increase the torsional stiffness and energy-dissipating capacity of the C-joint, a joint with ' strong connection and weak plate' is proposed based on the conventional seismic principle ' strong joint and weak member'. Firstly，rational dimensions of the components were determined preliminarily through relative specifications and theoretical analysis ； secondly, the nonlinear finite element model was established using the finite element software ABAQUS ； thirdly, the rational dimensions of the joint components were determined through the optimization analysis carried out on the finite element model. At last, the experimental study was carried out on the proposed C-joint to investigate its mechanical characteristics. It is shown that ： the proposed novel joint provides favorable ductility and torsional stiffness ； the stiffness and ultimate bending of the joints increase with the increasing of the thickness of the side plate and front plate ； the material constitutive model for the cone head of the joint affects the simulation results greatly and the trilinear material constitutive model is proper for the simulation. [ABSTRACT FROM AUTHOR]

Copyright of Oil Drilling & Production Technology / Shiyou Zuancai Gongyi is the property of Shiyou Zuancai Gongyi Bianjibu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Guangdong University of Technology is the property of Journal of Guangdong University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In 2014, soybean production was 179 million tons, and planting area was 102.1 million square hectare in China. China has become the fourth largest soybean production country after the United States, Brazil and Argentina over the world. However, the green soybean harvest still rely on manual power, what’s more, harvesting has taken up the large part of labor force in green soybean planting, accounting for over 40% of the total labor force. The operation of pod taking off is a key link in the process of green soybean mechanization harvest, and meanwhile, it is a core factor and technology which seriously influences the equipment performances. The structure style of the device of pod taking off and its parameters selected for working directly determine its harvest capability of fresh soybeans and other legume crops. Therefore, a green soybean separation experiment device of 5TDS-00 type manufactured by Nanjing Research Institute for Agricultural Mechanization was designed to research the separation properties of green soybeans based on striking, in order to seek the optimal combination of the factors influencing the separation effect. This experiment device of pod taking off consisted of rollers of pod taking off , conveying mechanism, angle adjuster, distance adjuster, driving speed-adjusting motor, roller speed-adjusting motor and so on. The device was driven by motor and fed by chain conveyor, and could realize step-less speed regulation under the coordination of angle adjuster, distance adjuster and adjustable speed motor. After striking, the green soybean would generate the variable motion inertia force, which could overcome the pod-handle connection force so as to achieve the objective of separation. The energy collision model of the separation process and the mechanical model of pod-handle separation were constructed based on the principle of energy conservation. Quantitative analysis was done to verify the energy collision model and the mechanical model. The roller speed, feeding speed and roller distance were supposed to be the main influence factors. In the end, focusing on “Xiaonongqiuyan” and “Doutong 6” varieties, the experimental investigations were carried out. The test green soybean was derived from Hentang Export Vegetable Base in Changshu City, Jiangsu Province, and the sample collecting dates were from August 1st to 7th in 2014. Under the same climatic condition, the samples possessing the similar shape and quality could be chosen. After that the rapid refrigeration was needed and the storage temperature was set at -2-0℃. Moreover, the research should be completed within 24 h. The results showed that the crop variety had little impact on damage rate and separation rate. The order of the aggregative indicators according to their influence from major to minor was the roller speed, the feeding speed and the roller distance. When the roller speed was set at 600 r/min and the roller distance was set to 18 mm, and at the same time, the feeding speed was set at 0.3 m/s, the harvest rate could attain 99.0% and the damage rate could be reduced to 2.4%, achieving a good comprehensive property. The prototype field experiments showed that the production efficiency could be up to 3-5 mu every hour, which was more than 20 times the manual operation. The result of this paper can provide a theoretical foundation for the design of the green bean harvest device. [ABSTRACT FROM AUTHOR]

Knock-out drum in the flare system can avoid rain of fire because it can effectively separate droplets or solid impurities from the vent gas and reduce the amount of condensate in the gas. Therefore, knock-out drum plays a key role for the safety of the flare system and the protection of the environment. In the paper, FLUENT software was applied to simulate the effect of droplet diameter, the pressure difference between the inlet and outlet, working temperature, liquid holdup of the gas and length-diameter ratio on separation efficiency of horizontal knock-out drum. The results showed that properly increasing the droplet diameter, working temperature and length-diameter ratio of knock-out drum, decreasing the pressure difference of the inlet and outlet, liquid fraction can benifit to increase the separation efficiency of the knock-out drum. [ABSTRACT FROM AUTHOR]

With the use and depletion of fossil fuels, environmental pollution and energy crisis have become the biggest obstacles to the survival and development of human beings. Biomass energy utilization is an important way to solve this problem as it has wide source of raw material, and is clean and renewable. Biochar is an important form of biomass energy utilization, and it can not only change the waste straw into biomass energy, but also help reduce the greenhouse effect. The yield is a basic index in the study of pyrolysis technology; while the biochar is used as fuel, its calorific value is the factor directly reflecting the quality. These 2 indices are both necessary during the research. However, the existing research on the pyrolysis process of biochar is limited to all kinds of independent indices, and the optimal pyrolysis process is always not the same. In this paper, the advantages and disadvantages of pyrolysis process for biochar production were evaluated by the yield, calorific value and energy efficiency in order to design and optimize the process of carbonization of cotton stalk. The effects of the temperature, retention time and particle size on the yield and heating value of the biomass were studied; and the typical cotton stalk was taken as raw material to produce biochar under nitrogen gas atmosphere by slow pyrolysis. The results showed that: 1) The effects of pyrolysis temperature on the yield and heating value of the biomass were significant; the biochar yield was negatively correlated with heating value, and with the increase of the temperature, the yield of biochar decreased gradually, while the calorific value increased gradually. 2) The effect of retention time on the yield and heating value of the biochar was obvious, but it was not as obvious as the pyrolysis temperature; at the same time, it could be seen that the yield and heating value were negatively correlated, and with the increase of the retention time, the biochar yield decreased, while the calorific value increased. 3) Compared with the first 2 conditions, there was no significant change in the yield and heating value when the raw material particle size changed, which showed that the effects of particle size on the yield and calorific value were small. In addition, according to the general trend, we could still see a negative correlation between heating value and yield. Energy efficiency (ratio of total energy yield of biochar to energy yield of raw material) was proposed to coordinate the yield and calorific value, and the response surface analysis of the energy efficiency was carried out, from which the energy efficiency model was got. The results showed that when the temperature was 429℃, the retention time was 1.29 h, and the particle size was 0.32 mm, the predicted energy efficiency from the model reached the highest value, which was 78.95%. The model is validated by the experiment. The model can be used to guide the production of biochar with high energy efficiency, and provide the reference for energy efficient utilization. [ABSTRACT FROM AUTHOR]

Solar water heaters are widely used in urban and rural China. The Home Appliances to the Countryside program from government further expands its application in rural areas. In the end of 2010, there were 168 million square meters of installed solar heaters, with an annual primary energy saving of 20 Mtce. The total installation is very likely to reach 250 million square meters in 2015 and at least 600 million square meters in 2020. In the 2009 Copenhagen UN Climate Change Summit, president Hu Jintao pledged to the international community to reduce the CO2 intensity of the economy by 40% to 45% by 2020 on the baseline level of 2005. Meanwhile, the share of non-fossil energy is also expected to rise to 15%. Application of solar water heaters will help to achieve this goal. The thermal performance of the flat-plate type solar energy water heater has been studied globally. In order to ensure the efficient operation of the solar water heater and user's demand to the terminal temperature of a tank, the countries all over the world with different climate have given different recommended value for water-mass-to-collector-area ratio (the ratio is abbreviated as MAR) of the flat-plate solar water heater. However, China has a vast territory and its climate is complex. The value range of recommended value from literatures is too large to be used to practical application. The main residential buildings in large and medium-sized cities are mostly high-rise buildings. The solar water heater installed on roof can only meet hot water use for the top six to eight floors. The application of the balcony wall-mounted solar water heater is one of the effective ways to solve hot water needs for the rest of users in high-rise buildings. Based on the typical meteorological data of nine cities in mild region of China, the values of MAR of the balcony wall-mounted flat-plate solar water heater have been calculated by using the established mathematical model. The water tank terminal temperature of 60°C, the collector angle of 60°-90° and the azimuth angle of 0-90° were used in model analysis. Calculation results for south-facing balcony wall-mounted solar water heater in mild region showed that the appropriate MAR of spring, summer, autumn, winter and the whole year was 28-51, 21-41, 31-53, 37-57 and 31-47 kg/m2, respectively. For convenience of practical application, the linear regression relation between seasonal and annual average MAR and the tilt angle for south-facing balcony wall-mounted solar water heater. The correlation coefficients between them were greater than 0.99. In this paper, we introduced a new concept "azimuth factor of MAR" which was easy to calculate MAR for the collector with different azimuth angle. For the non-south-facing balcony wall-mounted solar water heater, the seasonal and annual average azimuth factors of MAR decreased with the increase of the azimuth angle. The seasonal and annual average azimuth factors of MAR ranged from 0.57 to 1.00 and 0.72 to 1.00 when the tilt angle and azimuth angle were respectively at 60°-90° and 10°-90°. The azimuth angle had about 5% effect on MAR for winter and spring, summer, autumn and the whole year when the azimuth angle was less than or equal to 20° and 30°. The azimuth angle had about 10% effect on the above-mentioned MAR when the azimuth angle was less than or equal to 30° and 40°. In conclusion, the annual average solar fraction ranges should be in 0.55-0.70 for the south-facing balcony wall-mounted flat-plate solar water heater used in mild region of China. [ABSTRACT FROM AUTHOR]

This study was aimed to prepare the whey protein isolate (WPI) - sodium tripolyphosphate (STPP) aggregates using heating at higher pH value and evaluate their characteristics. The results of single-factor experiment showed that the increase of viscosity of polymers was different from the increasing of WPI concentration, temperature, pH value, STPP content and aggregation time. The models were obtained by using a Box-Behnken optimization experiment design with the 4 factors (temperature, pH value, STPP content and aggregation time) based on the results of single-factor experiments. The results of Box-Behnken optimization experiment showed that the order of the effect of the 4 factors on viscosity was as follows: temperature > STPP content > pH value > aggregation time. The optimized condition determined was that 10% (w/w) WPI, 0.09% (w/w) STPP at 90°C for 42 min with pH value of 8.40, and the actual viscosity was 5083 mPa·s. The prepared WPI-STPP thermal aggregates were the thick sample with a semi flow state, and the regression model was fitted well. Determination of properties and structural analysis of WPI, WPI-STPP thermal aggregates and WPI aggregates showed the water holding capacity, surface hydrophobicity and rheological characteristics of WPI-STPP thermal aggregates were improved compared with WPI and WPI aggregates. For WPI aggregates, water holding capacity increased from 4.83 to 5.20 g per gram protein (P<0.05). However, the solubility of WPI-STPP thermal aggregates decreased from 88.5% to 34.50%, which was lower than that of WPI. Heat treatment and STPP significantly affected the surface hydrophobicity of the soluble aggregates. WPI-STPP thermal aggregates could form good cold-induced gels, which could widen its application in foods of gel type. When STPP was added, the average particle size of whey protein thermally polymerized increased from 31.39±1.81 μm for WPI to 292.09±2.17 μm for WPI-STPP thermal aggregates. The difference between strong and weak soluble gels could be assessed by the oscillatory dynamic experiments using parallel-plate geometries. Rotational rheometer showed that the rheological characteristics of WPI-STPP thermal aggregates were improved. The rheological characteristics were determined from storage and loss moduli as the functions of time and frequency. WPI-STPP thermal aggregates had higher storage modulus values. The results showed that the increasing of particles played a significant role in the water holding capacity and rheological properties of these dispersions. The microscopic structure analysis of WPI-STPP thermal aggregates showed that they denatured fully, and the larger irregular fractal aggregates of WPI-STPP thermal aggregates could be most useful to increase the viscosity. Transmission electron microscopy showed that heat-induced WPI-NaCl soluble gels had a dense structure and a higher number of cross-links. The utilization of WPI-STPP thermal aggregates is very attractive due to the low-complexity processing conditions needed, lower production cost and higher nutritive value. The production cost of yogurt is less than yogurt with pectin according to the optimal technological condition of the experiment. The application of this technology proposed in this paper will bring great economic benefits for the yogurt processing industry. [ABSTRACT FROM AUTHOR]

The high-speed centrifugal compressor used in the air supply system is the major noise source of the fuel cell vehicle. Therefore, it is important for the compressor to achieve low noise level as well as high compression ratio and efficiency. This paper presents an optimal design method for the centrifugal compressors using numerical simulation, Kriging model and genetic algorithm at the operating point. The rotational speed at the operation point is 80 000 r/min, the mass flow rate is 0.08 kg/s, and the compression ratio is 1.65. The steady RANS simulations are preliminarily used to provide the performance maps as well as the consistent initial conditions for the subsequent unsteady simulations. Performance maps are compared between numerical and experimental results at 40 000 and 50 000 r/min, which show a good agreement. Next, the unsteady simulations are performed to calculate the sound power level of the compressor. In order to analyze the influences of the blade inlet angle, blade outlet angle, trailing edge angle, tip clearance and blade thickness on the compression ratio, isentropic efficiency and sound power level, the optimal Latin square design is adopted to create the sample space. Each one of the sample points is simulated with the presented numerical method. The results show that the tip clearance and blade thickness are 2 primary factors. The compression ratio and efficiency decline when the tip clearance and blade thickness decrease, while the sound power level rises. The front incline is found to be better than the back incline. The Kriging model is built to reflect the functional relationship between the impeller design parameters and the performance parameters. Then, the multi-objective optimization is conducted with the genetic algorithm based on the Kriging model instead of the numerical model. The errors of the compression ratio, isentropic efficiency and sound power level between the Kriging model and the numerical model at optimized point are 0.11%, 0.46% and 0.01%, respectively. The blade inlet angle, blade outlet angle, trailing edge inclined angle, tip clearance and blade thickness of the baseline design are 37°, 45°, 26.7°, 0.3 mm and 1.2 mm, and the optimized design are 35.226°, 50.863°, -2.465°, 0.365 mm and 0.611 mm, respectively. Compared with the initial design, the compression ratio and isentropic efficiency of the optimal design are increased by 3.56% and 1.02%, respectively and the sound power level is decreased by 3.79 dB. The sound pressure spectrums show that the noise at blade passing frequency decreases by 16 dB. The rotational frequency and its noise at the harmonic frequency as well as broadband noise at the 0-1 800 Hz and 10 000-16 000 Hz also decrease. The compression ratio and isentropic efficiency of the centrifugal compressor are also improved at the off-design points. Internal flow fields are analyzed to find out the mechanism of the improvements. The results show that the velocity distribution is more uniform and the secondary flows in the blade flow channel significantly decrease after optimization, which means that the mixing loss at the impeller outlet decreases. This research provides a reference for optimizing the acoustic behavior as well as the performance parameters of centrifugal compressors at the early design stage. [ABSTRACT FROM AUTHOR]

Notoginseng is one of rare medicinal herbs in China, and it is mainly grown in Yunnan Province. Market demand of notoginseng is very large, and hence, until December 2014, the planting area of notoginseng has reached 40000 hm2. At present, the main planting pattern is through manual operation, and the labor intensity is very high and the sowing quality is discrepant. However, there is no precision seeding device suitable for notoginseng. Therefore, the mechanization planting of notoginseng has important practical significance. Notoginseng is planted on small plots of land, the planting density and the requirement of seeding precision are high, so we designed a small sized precision metering device. The liquidity of the seeds is not good and the shape of seeds is irregular for notoginseng, so we chose the pneumatic seed-metering device to adapt to the characteristics of the seeds accordingly. In order to meet the precision seeding requirements of notoginseng planting, a unique pneumatic cylinder-type precision metering device was designed. This device integrated the features of vacuum suction, insulated pressure for seed-clearing and zero speed of seed dropping. In this paper, the main structure and the working principle of the metering device were expounded. The pitch-row of the hollow shaft was determined and the stability of the flow field was ensured by the flow field analysis through the computational fluid dynamics (CFD) software. The key structure parameters were determined through theoretical calculation according to planting requirements. The contrast test of dropping seed indicated that zero speed of seed dropping was necessity. According to the extensive testing combined with the experimental results of relevant scholars, the main factors which affected seeding performance of pneumatic cylinder precision seed-metering device were determined, which were forward velocity, negative pressure and adsorption angle. During the test process, in order to reach zero speed of seed dropping, the installation angle of adjustable insulated pressure plate was changed with forward velocity. The notoginseng seeds in Wenshan were chosen for sowing object. Based on the three-factor five-level quadratic orthogonal rotating combination test method, the influences of forward velocity, negative pressure and adsorption angle on sowing performance were explored. The experimental results showed that the influence of negative pressure on the qualified rate was very significant (P<0.01), and the influences of forward velocity and adsorption angle were significant (P<0.05). The regression equations of the 3 factors were fitted through the processing by Design Expert 8.0.6 (experimental design expert) software. Based on the results of examination, we found that the fitting of the equations was good, the best parameter combination was adsorption angle of 20°, negative pressure value of 660-720 Pa and forward velocity of 0.72-0.76 m/s, and under the optimal condition, the qualified index was greater than 90.2, the missing index was less than 4.9, and the multiple index was less than 5.3. The pneumatic cylinder precision seed-metering device met the standard and requirements by comparing the results with the national standard and notoginseng planting requirements. This approach of research is suitable for the exploitation of notoginseng seed-metering, and provides a theoretical reference for the design of pneumatic cylinder precision seed-metering device for Panax notoginseng. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

China is one of the major rapeseed production countries in the world, but the harvesting mechanization is still backward, and high mechanical harvest loss is a key inhibiting factor for rapeseed production. In order to reduce the harvest loss ratio, the effects of the parameters of air-screen cleaning device of rapeseed combine harvester on cleaning loss ratio and percentage of impurities in grain under the actual field harvest operating condition are needed to understand. In this paper, a Plackett-Burman test and a response surface test were designed to study the 4 parameters: vibration screen amplitude, crank revolving speed, fan revolving speed, and fan dip angle based on a two-roller and air-screen field mobile harvest testbed. The Plackett-Burman experiment results showed that the vibration screen amplitude and the crank revolving speed had significant influences on the cleaning loss ratio, and the effect of the amplitude was greater than that of the crank revolving speed, but the fan revolving speed and the fan dip angle had not significant impact; the results also showed that the fan revolving speed had significant influences on the percentage of impurities, while the other 3 parameters had not significant impact. The response surface regression variance analysis showed that the effects of the 4 parameters were not the linear relation but the interaction; the predicted values of quartic polynomial regression model were consistent with the measured values in the experiment, and the regression models of the cleaning loss ratio and the percentage of impurities were solved and the values of R2 were 0.9559 and 0.9660 respectively. The single factor and two-factor analysis results indicated that the vibration screen amplitude had a little impact on cleaning loss ratio near zero level, reducing the crank revolving speed could remarkably lower the cleaning loss ratio, and increasing the fan revolving speed could remarkably lower the percentage of impurities. A group of optimal parameter combinations under the constraint condition could be acquired by solving these regression equations, and a checking test was carried out by using an approximately optimal parameter combination: vibration screen amplitude of 35 mm, crank revolving speed of 392 r/min, fan revolving speed of 1 750 r/min, and fan dip angle of 29°. The cleaning loss ratio and the percentage of impurities were 0.90% and 0.45% respectively in the test, but when these parameters were applied into the regression mathematical models, the cleaning loss ratio was 0.38% and the percentage of impurities was 0.48%, and the absolute errors were 0.52% and -0.03% respectively. Compared with the field result that was based on the common parameters, the cleaning loss ratio dropped by 61% and the percentage of impurities dropped by 58%. The analysis results indicated that the relationship between the parameters of cleaning device and the cleaning loss ratio and grain percentage of impurities was correct and the precision of regression mathematical model could meet the need for optimizing the parameters of air-screen cleaning device. The results can provide theoretical basis and technical references for the parameter selection and optimization of air-screen cleaning device of rapeseed combine harvester. [ABSTRACT FROM AUTHOR]

This paper introduced the main problems existing in low load operation conditions of sulfur recovery plant, and the causes of the problems were analyzed. According to the analysis, the proposals and measures of operation optimizing of the sulfur recovery unit under low load were put forward, which could provide references for safe, smooth operation of sulfur recovery unit and achieve the up-to-standard emission of tail gas. [ABSTRACT FROM AUTHOR]

Seedlings transplanting plays an important role in the process of vegetable production, and mechanized transplanting can reduce the labor intensity, improve the production efficiency and ensure the work quality. The chili seedling transplanting mechanization technology has been vigorously developing in Xinjiang region. However, at present, there is no automatic vegetable transplanting machine available in Xinjiang. The chili seedling transplanting work basically relies on manual operation, and some transplanters used are semi-automatic machines, which still need manual work to pick up and drop seedlings. Therefore, it is very important and urgent to study the automatic pick-up mechanism for chili plug seedling. Based on the situations above, a kind of automatic pick-up mechanism for chili plug seedling was studied and analyzed in order to replace the manual work. The mechanism consisted of a planetary gear train, a curvy cam, a connecting rod and a pick-up seedling arm in which 2 seedling claws were installed. As the transmission of the mechanism, the planetary gear train drove the seedling pick-up arm to carry out reciprocating movement in curvy cam for picking up seedlings once every rotation. Compared with the existing pick-up mechanisms for vegetable seedlings, the mechanism proposed in this paper was simplified and its stability was improved. It could not only pick up and transport seedlings, but also drop seedlings in the vertical direction at the same time, which ensured that plug seedling had good planting upright degree. Moreover, the endpoint trajectory of the seedling needle was more easier to control. Based on the analysis of structure features and working principle of the automatic seedling pick-up mechanism, its kinematic mathematical model was established, and the displacement, velocity and acceleration equations were also analyzed. Then, a computer-aided analysis program based on Visual Basic 6.0 was developed for optimizing structural parameters of the mechanism. By means of the human-computer interaction analysis method and the software of Adams, certain structural parameters influencing the regularities of the seedling needle endpoint trajectory were analyzed, and then optimized to satisfy the requirements of picking up chili seedling. Therefore, the ideal movement locus of seedling pick-up needle endpoint and a group of optimized structural parameters were acquired conveniently. According to the optimized structural parameters, the three-dimensional entity model of mechanism was established and the automatic seedling pick-up test-bed was developed. The kinematic simulation analysis and seedling pick-up prototype tests were carried out in the Key Laboratory for Xinjiang Production and Construction Corps Agricultural Machinery. The results showed that the seedling needle endpoint’s relative trajectories obtained from high-speed camera were consistent with the theoretical ones. According to the seeding pick-up experiment, the success rate of seedling pick-up reached 98.6%, the loss percentage of plug seedling substrate was 4.2%, and the success rate of dropping seedlings attained to 94.2%, which indicated that manufactured pick-up mechanism met the requirement of actual testing. The seedling pick-up experiment further proved that the mechanism could not only satisfy the demands of chili seedlings automatic mechanical pick-up, but also apply to other vegetables, such as tomato. The research method was also proved to be accurate. The study for the automatic pick-up mechanism provides very important theoretical basis and reference for the design, analysis and further study on automatic pick-up and transplanting mechanism. [ABSTRACT FROM AUTHOR]

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Traditional image interpolation method always only focuses on relationship between adjacent pixels of partial image to interpolate，ignoring non-local self-similarity for extensively existing image. In order to fully utilize the non-local self-similarity in image to improve quality of inter;polated image, this paper proposed a novel image inter;polation metliod based on nonlocal l〇-w-rank matrix reconstruction model of image. It also presented efficient iteration solution algorithm for low-rank reconstruction model. The given algorithm could obtain higher objective and subjective reconstructed image quality. Furthermore， experiment shows that compared with Bicubic，SAI，etc.，image interpolation method can generate PSNR gain with average of 1. 37 dBand 0. 77 dB [ABSTRACT FROM AUTHOR]

In order to solve the problem of high traction resistance of the traditional subsoiler, a forced-vibration subsoiler was designed and developed. This paper introduced the structure and described the working principle of this forced-vibration subsoiler. What was more, the motion process of the vibrating deep loosening shovels was analyzed and the motion equation of the shovel point was established. Type of forward velocity, vibration frequency and vibration angle were selected as 3 factors of the orthogonal simulation experiment to evaluate their effects on traction resistance, total power and torque in the soil-bin experiment. The sequence of factors in affecting the traction resistance was vibration frequency > forward velocity> vibration angle. The traction resistance was reported to increase consistently with the increasing of forward velocity. The sequence of factors in affecting the total power was forward velocity > vibration frequency > vibration angle, and the total power values firstly increased and then decreased with the increasing of vibration frequency while the total power values firstly decreased and then increased with the increasing of vibration angle. The sequence of factors in affecting the torque was vibration frequency > forward velocity > vibration angle, and the torque values firstly increased and then decreased with the increasing of forward velocity while the torque values consistently increased with the increasing of vibration frequency. The optimal combination of the performance parameters was the forward velocity of 2 km/h, the vibration frequency of 10Hz and the vibration angle of 12°. For further validating the rationality of optimal combination of parameters, the test on working performance of the forced-vibration subsoiler was carried out in the experimental field, and soil properties (bulk density and water content), soil bulkiness, soil disturbance coefficient and traction resistance were selected as the evaluation indicators to compare with non-vibration subsoiler. The results showed that the bulk density of all soil layer decreased after forced-vibration sub-soiling and that at 0-15 cm soil layer decreased by 21.74%. At the same time, the water content at 15-25 cm increased by 16.02%. The variation coefficient and stability coefficient of sub-soiling depth, which were the indicators to the change quantity and degree, were 7.37% and 92.63% respectively. Meanwhile, the variation coefficient and stability coefficient of the depth reached the requirements of the Ministry of Agriculture, and the land surface was smooth and flat after sub-soiling. Moreover, soil disturbance coefficient was 57.11% after subsoiling and soil bulkiness was 36.96%. Both soil bulkiness and disturbance coefficient reached the requirements of the test indicators. In addition, the traction resistance was reduced by 9.09% compared with non-vibrating subsoiler, so the effect of reducing traction resistance was obvious. These results provide a reference for further optimization of the mechanical structure and improving dynamic and economic performance of the whole machine. [ABSTRACT FROM AUTHOR]

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Piccolo was the one of important lightweight cryptographic algorithms as IoT cipher in the recent years. This paper researched the hardware optimization method of Piccolo encryption algorithm. The same round operation was achieved only once and repeated call. The original algorithm of Piccolo had r round operation. The key size of Piccolo was 80-bit/128-bit, the corresponding round number was 25/31．The optimal method made the r-1 round repeated calling into the r round operation repeated calling. It constructed a RP-1 function after the r round operation. The experimental results show that the optimal method of Piccolo-80 can save 3227 Slices for hardware implementation. Optimize efficiency reached 24.6%.Encryption rate increased by 10%. [ABSTRACT FROM AUTHOR]

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With the vigorous promotion of the national strategy for hydraulic engineering, a demand for mixed-flow pump in infrastructure has been increasing for years. As a kind of high-performance pump, the high specific speed mixed-flow pump has the advantages of stable performance and wide application area. With the increasing of specific speed, the high specific speed mixed-flow pump has begun to replace the axial-flow pumps in some application areas in recent years. It is necessary to optimize the impeller performance for it affects the pump performance directly. The velocity torque distribution along mixed-flow pump impeller is a significant parameter, which plays an important role in energy conversion between impellers and fluid. In the design of dualistic theory of mixed-flow pump impeller, the regulation of velocity torque distribution should be defined. But, there is no uniform method of expression as well as specific rule for designers to follow, and too much experience is needed to rely on. It has far-reaching meaning for the promotion of the level of mixed-flow pump design and the performance by establishing the optimization parameter model of velocity torque distribution along impeller. In order to further research the hydraulic performance of optimization method for high specific speed mixed-flow pump, a mixed-flow pump whose specific speed is 803 was chosen as the research object, and the commercial software CFX and the shear stress transport turbulence model were applied to compute the interior flow field within the pump. In this paper, the efficiency and the head were chosen as the optimization objectives, and 3 parameters that describe the velocity torque distribution were chosen as the optimization parameters, which were used to parameterize the impellers. The uniform design was adopted to arrange the sample space, the RBF (radial basis function) neural network was used to fit the relationship between the variables and objectives, and finally the NSGA-Ⅱ genetic algorithm was used for multi-objective optimization. Moreover, the difference of the internal flow field was obtained by comparing the initial linear distribution individual with the optimal efficiency individual and the optimal head individual respectively, which were selected from the Pareto solutions. The velocity torque distribution and the change trends of the wrap angel along the axial plane streamline between the initial and optimal individual were analyzed. The wrap angel values of optimal efficiency and optimal head were 75.15° and 67.85°, respectively. The variation trends of the wrap angel of micro-element based on optimal efficiency individual were contrary with the initial one, while the variation trends based on optimal head individual were the same as the initial one, but the change range was enlarged. Compared with the initial linear distribution individual, the efficiency of the optimal efficiency individual was improved by 1.12% through experimental verification. Distribution maps of the relative streamline, velocity and static pressure of the impeller guide vane at 0.5 times blade height and the static pressure of the corresponding chord length at 0.2, 0.5 and 0.8 times blade height were showed. And, the possible reasons for the differences between initial individual and optimal individuals were given. It was found that, utilizing the RBF neural network combined with NSGA-Ⅱ genetic algorithm, the effect of optimizing the impeller hydraulic performance of high specific speed mixed-flow pump was remarkable. The research provides a certain theoretical reference for further improvement of the performance of high specific speed mixed-flow pump. [ABSTRACT FROM AUTHOR]

According to Tianjin metro line 3 and line 6 transfer station Beizhan station engineering, through specific and reasonable technical measures, scientific construction management, optimized key nodes, on-site real-time monitoring measures, we ensured the metro station safety of the existing metro line 3, the normal traffic interchange station operating vehicles, and the transfer station construction safety. This paper can provide experience for the future similar transfer station construction. [ABSTRACT FROM AUTHOR]

In the application environment where measuring the temperature in the process of industrial heating, the reconstruction algorithm is the key to realize the measurement of temperature field by using ultrasonic. In order to solve the problem, this paper developed a reconstruction optimization algorithm without changing the number of effective ultrasonic wave. It used the perfect function approximation ability of Gaussian radial basis function to implement the mapping relations between the sound wave propagation velocity and the temperature distribution, then reconstructed the measured temperature field through the matrix singular value decomposition. The algorithm had reconstructed four kinds of typical model of temperature field: unimodal skewed, unimodal symmetric, bimodal deflection and bimodal symmetrical under different Gaussian noise interference in the simulation experiments. The simulation results have proved that the algorithm has the advantages of high reconstruction precision, strong anti-jamming capability and fast response speed. [ABSTRACT FROM AUTHOR]

A large amount of energy is consumed during the pumping station operation, especially for the pumping station that water level of the forebay varied frequently in a wide range, pump units often run deviating from the high efficient area of pump, this results in energy waste. In order to lift water, some energy dissipation devices and flow facilities are used such as main pump unit, inlet and outlet passages, forebay and outlet sump, auxiliary equipments, power transmission and substation facilities, etc. Usually, the source water should be transported in a certain distance by the river or channel to the destination. Hydraulic loss and water loss of the river are integrated into power losses of the water. Further more, the operation performance of the pumping station is influenced. In this paper, hydraulic loss, evaporation loss and leakage loss were all considered. Based on variations of source water level, under certain water level of water transfer destination, the unknown water level, flow rate and river parameters could be obtained by the given parameter data based on energy conservation equation in fluid mechanics. Then, the relationships were determined respectively between demanding discharge of destination and pumping head, and between demanding discharge of destination and pumping discharge. The results showed that the relationships were nearly linear. Applying the linear relationships to the later optimization process in the algorithm, the repeated water level iteration was avoided. Also, the calculating amount and calculating time were reduced greatly. Taking three typical tidal level differences of maximum, mean, and minimum at Sanjisngying Intake of Yangtze River as a case, under certain water level and demanding discharge of Huai’an pumping station downstream, the model was built based on the system concluding main pump units, auxiliary equipments, power transmission and substation facilities, and water transferring facilities. The optimizing goal was the least daily operation cost, and the constraints included source water level, water level and flow rate of destination and each cross section of the river, single machine flow rate, the number of running pumps, and the balance of hydraulic loss and water loss. Also, the model was solved by Simulated Annealing-Particle Swarm Optimization Algorithm (SA-PSO), which had better global and local searching ability. Pump blade angles and the number of running pumps were defined as variables, and the objective function was chosen as the fitness function in the algorithm. The pump assembly performance at some blade angles could be got by fitting or interpolation. The results indicated that when the daily varied range of Sangjiangying water level was small, the operation cost was low because of high Sangjiangying water level and low head of Jiangdu pumping stations. When the daily varied range of Sangjiangying water level was large, it turned out the opposite. The cost could be saved by 0.62%~2.26%, 0.33%~3.26% and 0.22%~0.83%, respectively by adjusting pump blade angles than that of design blade angles. If the water-conveyance performance was considered, the optimal operation schemes were more reasonable. The methods could be applied in optimal operation for other pumping station system. [ABSTRACT FROM AUTHOR]

In view of the problem of optimizing the initial value in GM(1,1) model, as criterion of the objective function with the minimum of the square sum of the error and the model test with the minimum of average relative error is inconsistency, leads to the optimization effect is not very good. In this paper, optimizing the GM(1,1) model with the minimum of the square sum of the relative error as the target, respectively optimizing the initial condition and the initial point, the algorithm of optimize formula is given. It proved that under the criterion of minimum the square sum of the relative error in original sequence, the initial conditions optimization and the initial point optimization are unified. Examples show that the results of average relative error calculated by optimizing formula are in close proximity to the numerical solutions. Using the optimization formula to calculating is more convenient than the numerical solution. [ABSTRACT FROM AUTHOR]

Aiming at the problems of newly-built supercritical and ultra-supercritical once-through boilers influencing the project of trial operation during debugging, including low quality of steam and water, and low speed of qualification, this paper expounds the resource and harms of impurities in thermal power system of newly-built units, analyzes the factors influencing steam-water quality and proposes optimization measures, including installation control, optimization of assay, application of analytic instruments and chemical cleansing. The time- consuming for silicon cleaning is shortened obviously and oil, coal and water are economized. These measures could be referenced for improving steam-water quality by other large capacity and high parameter generator units. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Capital Institute of Physical Education is the property of Shoudu Tiyu Xueyuan and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to explore the impact of iteration in the R&D project on schedule and cost of projects, this paper analyzes the rework change propagation and builds the rework factor design structure matrix (DSM) based on the direct and indirect rework probability. The impact of rework change propagation, the time and scope of iteration on rework risk are also analyzed. Then, for reducing the rework impact strength, the method of rework pretreatment is proposed and the model of rework impact after pretreatment is built. Furthermore, the model of project's net value is proposed based on the rework pretreatment and rework risk models. The process DSM optimization objective is to maximize the project's net benefit. Finally, an industrial example is provided to illustrate the proposed models. Results indicate that the optimized DSM can reduce the project risk and increase the project's net benefit significantly. [ABSTRACT FROM AUTHOR]

In order to investigate the important influence of hoisting machinery allocation on the installation of thermal power system boiler, this paper analyzes, taking No. 5 and No. 6 unit project of the 4 X 330 MW unit in the second phase of Shandong Weiqiao-Lvdian-Zouping three power plants technical transformation project, boiler hoisting allocation and its advantages and disadvantages, and the key points of the hoisting of boiler equipment, and makes an attempt to accelerate hoisting by using 2 hoisting machineries. The result shows that the scientific boiler hoisting machinery allocation is key to the insurance of project duration and is influential in the progress rate and construction cost of unit installation. [ABSTRACT FROM AUTHOR]

In recent years, carbon dioxide and other greenhouse gas emissions has increased dramatically, which brings about seriously environmental problems. Low-carbon environment obtains more and more attention. This paper established a multi-objective low-carbon loop supply chain network optimization model. The optimization objectives of the model were to minimum carbon emissions and cost. According to the characteristics for the model, it combined genetic algorithm and ε constraint to program based on genetic algorithm toolbox of sheffield university and MATLAB 7. 6 platform. It obtained the dual objective Pareto optimal solution. And it verified the effectiveness of the algorithm. Different from the previous models, this model substitutes reprocessing plants with repairing centers, dismantling centers and decomposition centers, which refines the subjects of reverse supply chain network. It discussed the impact of waste products utilization coefficient and distribution coefficient on the range of Pareto optimal solution. This impact varies with different coefficients. It also analyzed the reasons of this impact. Finally, it also studied the impact on the scope of optimal results in the conditions of random demand of products and random demand of waste products. Study shows little change in the range of optimal results. [ABSTRACT FROM AUTHOR]

Prediction is a means to analyse the future development trend which is generated in need of the development of so-cial economy. Grey prediction model is a kind of predicting method that is widely used in the application of prediction theory. Be same as other prediction methods, grey prediction model also has some existed limitations. So the study of grey prediction model is of great significance. This paper discussed the current using situation of GM(1,1)model. Through the analysis of for-mula, it pointed out the defects that was existed in this prediction model. Combined with the reasonable initial value selection, the model used the integral mean value theorem of fitting the real background values method, optimized the model to improve the model. Finally, it took the monitoring data of Shanghai Bailianjing river as the original data sequence, it applied and verified this model. Practice proves that the model accuracy is improved after optimization. [ABSTRACT FROM AUTHOR]

This paper proposed an accelerated linearized Bregman algorithm (LBreg) to solve sparse optimization. It had been proposed recently for approximately solving the basis pursuit problem. This methods were mainly based on two types of techniques: one was the Lagrange dual theory and the other was the preconditioning via singular value decomposition (SVD). By the Lagrange dual, LBreg was just the gradient method applied in minimizing a dual objective whose convergence rate was determined by the condition number of A. Thus,to accelerate LBreg,it employed the SVD to reduce the condition number of A. Moreover, the same was done to the inconsistence case of Ax = b by reducing the scale of dual problem via equivalent transformations. Numerical results demonstrate that the accelerated LBreg performs much better than the original LBreg. [ABSTRACT FROM AUTHOR]

Wheat straw is widely used as a kind of inexpensive, abundant, easily available, and sustainable raw material. At the same time, large amounts of wheat straw have still been burned on farmland in China, and have not been timely and properly applied. The smoke and dust from burning have highly adverse impacts on the environment. Therefore, it is urgent to study the pretreatment technology that is green, environmentally friendly, cost-effective and sustainable. Wheat straw was processed by physical methods, and the obtained raw fibers of wheat straw fiber mulch film were further pretreated by physical methods. In order to explore the influence of pulping process parameters on the pulp properties of the pulped raw fibers wheat straw fiber mulch film and the excellent pulp can be used to produce wheat straw fiber mulch film, the influence law of process parameters on the objective function was studied experimentally in this study. In the experiment, the whole wheat straw was pulverized by a crusher and the raw fibers of wheat straw fiber mulch film were obtained by a self-made straw fibers preparation machine. Taking the soaking water temperature, soaking time, beating time, beating load, and pulp volume as influence factors and the dry tensile index, beating degree and pulp fiber length as response indexes to evaluate the pulp properties. The five-factor and five-level (1/2 type) quadratic regression orthogonal rotation center combination design parameter optimization test method was adopt. The variances were analyzed using Design-Expert V6.0.10, and regression models were established between response indexes and influence factors. The analysis results showed that the beating time and the beating load had a very significant effect on the dry tensile index (P<0.01), and the interaction of various factors has no significant effect on the dry tensile index (P>0.05); the beating time, beating load, and the pulp volume had a very significant effect on the degree of beating (P<0.01), the interaction of soaking water temperature and soaking time had a significant effect on the degree of beating (P<0.05) while the interaction of the soaking water temperature and the pulp volume had a very significant effect on the degree of beating (P<0.01 ); beating time and beating load had a very significant effect on fiber length (P<0.01). The regression model optimization results were the soaking water temperature 63℃, soaking time 2 h, water volume of pulping pool 13.50 L, pulping load 4.57-5.50 kg and pulping time 0.25-0.68 h. Under such an optimized combination conditions, the response indexes of wheat straw fiber mulch film pulp processed as follows: the dry tensile index was greater than 5 Nm/g, the beating degree was less than 50 °SR, and the pulp fiber length was more than 0.9 mm, which indicated that the processed pulp could be used for manufacturing wheat straw fiber mulch film, and the wheat straw fiber mulch film could meet the technical requirements for covering and cultivating crops in wet and dry fields. [ABSTRACT FROM AUTHOR]

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