Parameter optimization of the transmission system based on an orthogonal test method

The aggregate gradation of asphalt mixture is one of the most important factors affecting the service life of asphalt pavement. In order to study the gradation of asphalt mixture with the best comprehensive performance, this study puts forward a new method of mineral aggregate gradation optimization based on the fuzzy analytic hierarchy process and comprehensive evaluation method, aiming at the multi-level and multi-index evaluation of the road performance of asphalt mixture. First, the orthogonal test design method is applied to design nine target gradations with coarse aggregate (>4.75 mm) and fine aggregate (<4.75 mm) of AC-20 (asphalt concrete) mixture serving as two factors and the upper, middle, and lower positions of the gradation curve as three levels, and then the road performance test research is carried out. Second, a comprehensive model for evaluation of road performance of mineral aggregate gradation is established. A fuzzy complementary judgment matrix is constructed, and the index weights of each level and the hierarchical total ranking weight are calculated. Then, the membership function is introduced into the comprehensive evaluation model for the road performance of mineral aggregate gradation, and the membership values of each index of asphalt mixture road performance are obtained. Finally, the fuzzy comprehensive evaluation method is used to find out the comprehensive evaluation value of the road performance of the nine graded asphalt mixtures, and the mineral aggregate gradation is optimized. The research results show that the 1# gradation of the asphalt mixture has the highest comprehensive road performance evaluation value, and the combination of the fuzzy hierarchical analysis process and comprehensive evaluation method can more objectively and comprehensively evaluate the comprehensive road performance of the asphalt mixture and provide a useful reference for the optimal selection of asphalt mixture mineral gradation.

Purpose: Preparation of gel-formed Dachuanxiong prescription. Method: In this experiment, liquid chromatograph is used to measure the content of gastrodin in gastrodia elata and orthogonal design method is adopted to optimize the technological conditions for extracting gastrodin. Comprehensive evaluation is conducted based on examination factors including dry powder, glycerol, hydroxypropyl methylcellulose and borneol as well as indexes including viscosity, appearance and spreadability, through which prescription can be screened and optimized, and gel-formed Dachuanxiong prescription can thus be prepared. Result: Content of gastrodin in gastrodia elata as raw material is 0.53%, and excipient should be gel made from 1 g of ethanol, 1.5 g of hydroxypropyl methylcellulose, 10 g of glycerol, 0.01 g of borneol and 100 g of water. Conclusion: This technology for preparation of gel is stable and simple, which can increase the content of ferulic acid obviously. Preparation of pure traditional Chinese medicine is delivered through nasal mucosa to relieve headache and mainly used to treat headache.[1]Chuanxiong Prescription was established by Liu Wansu, a well-known doctor living in the Jin and Yuan Dynasty. In this prescription, ligusticum wallichii can invigorate the circulation of blood and promote the circulation of qi, and gastrodia elata can relieve dizziness and pain. Combination of them can realize a good effect for the treatment of migraine caused by blood stasis and fire. This prescription is simple and effective. Based on physical and chemical properties of various medical materials, active ingredients in them can be extracted with the method of alcohol extraction. [2-4]According to result of document retrieval and patent search, volume fraction, number of times of extraction and time of extraction should be used as conditions of examination. [1]However, it can be verified through in-depth research on physical and chemical properties and pharmacological actions of medical materials in the prescription as well as repetitive tests that number of times of extraction have an obvious influence on extraction rate. Based on the above content, factors of examination in the experiment are determined and examination through orthogonal experiment is thus carried out, through which technological conditions that can realize a high rate of extraction of gastrodin (index component) is screened out. This experiment selects the optimal technology for extracting gel which can relieve headache and be delivered through nasal mucosa, in which orthogonal test method is applied, and content of gastrodin is viewed as an index. Ethanol should be used in the optimal extraction technology. The optimal technology is stable and practicable, which can obviously increase the content of ferulic acid.

The flow analysis of the forebay of a lateral intake pumping station with asymmetrical operating pumps was carried out with a realizable k-ε turbulent model and SIMPLEC (Semi Implicit Method for Pressure Linked Equations Consistent) algorithm. The Pressure Inlet boundary condition was adopted and the pressure between the top surface and the bottom surface was linear with the height of the inlet section. The Mass Flow Outlet boundary condition was also adopted to ensure the accuracy and precision of the CFD (Computational Fluid Dynamics) simulation. The diversion pier was selected as the optimization strategy based on the flow parameters. The layout of the diversion piers was designed with four parameters which are the relative length, relative height, width, and straight-line distance of the piers’ tail. Each parameter had three values. Based on the orthogonal test, nine groups of the numerical simulation on different layouts of diversion piers were analyzed with the uniformity of axial flow velocity and weighted average angle of the flow velocity of the inlet cross-section of each pump, reducing the number of tests from 64 (43) groups to 9 groups, improving work efficiency. The results show that the diversion piers had a significant adjustment of uniformity of axial flow velocity and weighted average angle of flow velocity. After optimization of the forebay, the uniformity of axial flow velocity of intake of No.1 pump was 80.26% and the weighted average angle of flow velocity was 77.68°. The above values of the No.2 pump were 98.74% and 87.84°, respectively. The values of the No.4 pump were 93.41% and 77.28°. The results of numerical simulation, which was carried out to estimate the rectification effect under the operation combination of the No.1, No.3, and No.4 pumps, showed that the uniformity and the angle of the No.1 pump were 92.65% and 72.66°, respectively, the uniformity and the angle of No.3 pump were 94.54% and 85.14°, and the uniformity and the angle of the No.4 pump were 75.81% and 78.21°. This research proves that the orthogonal test method, in a reasonable and convenient way, can be applied in hydraulic optimization for a lateral intake pumping station.

The main objective of this study is to present a method of determining viscoelastic deformation monitoring index of a Roller-compacted concrete (RCC) gravity dam in an alpine region. By focusing on a modified deformation monitoring model considering frost heave and back analyzed mechanical parameters of the dam, the working state of viscoelasticity for the dam is illustrated followed by an investigation and designation of adverse load cases using orthogonal test method. Water pressure component is then calculated by finite element method, while temperature, time effect, and frost heave components are obtained through deformation statistical model considering frost heave. The viscoelastic deformation monitoring index is eventually determined by small probability and maximum entropy methods. The results show that (a) with the abnormal probability 1% the dam deformation monitoring index for small probability and maximum entropy methods is 23.703 mm and 22.981 mm, respectively; thus the maximum measured displacement of the dam is less than deformation monitoring index, which indicates that the dam is currently in a state of safety operation and (b) the obtained deformation monitoring index using orthogonal test method is more accurate due to the full consideration of more random factors; the method gained from this study will likely be of use to diagnose the working state for those RCC dams in alpine regions.

Sheet forming is a high-volume fabrication method for producing lightweight materials components. An important goal in manufacturing research is to determine the optimum method for producing products with less cost. In this paper, combined with the orthogonal test method and finite element method (FEM) simulation, the analysis was carried out to analyze the key process factors such as stamping force, fillet radius, and friction coefficient. Using orthogonal test method can reduce the testing time, learn how the molding parameters influence the total equivalent plastic strain, acquire the best match forming parameters, and give guidance for the better condition

In order to solve the problem of low productivity, unqualified segment length and high energy consumption during the process of crushing square bale straw caused by improper operation parameters, a 9FF square bale straw crusher was developed. In this study, by taking maize straw as the test material, the feeding speed, spindle speed of the crushing device and the state of the crushing device were taken as influence factors, and standard straw length rate, productivity per net working hour (hereinafter referred to as NWH) and energy consumption per ton of product as test indicators, the influence of the factors on the indicators were studied, and tests were carried out on the process of square bale straw crushing. By adopting the single factor test on the effect of the feeding speed, the spindle speed of the crushing device and the state of the crushing device on the test indicators, the suitable range of each factor was determined, respectively. Using the orthogonal test method, range method, variance method and comprehensive balance method, the experiment analyzed the significance of the influence of the three factors on various indicators and the order of priority. The test results showed that: the feeding speed was 5 m/min, spindle speed was 3000 r/min, and the state of the crushing device was a mixing cutter hammer, which was the best parameter combination (A1B1C1) for the processing technology of the square bale forage crusher. The standard straw length rate was 93.7%, and the productivity per NWH was 2.80 t/h, with energy consumption per ton of 4.72 kW•h/t, in which the standard straw length rate and productivity per NWH reached optimal values, and the energy consumption per ton of product was slightly higher than the optimal value in the experiment. The research results can provide a reference for the optimal design of the special crusher for square bale straw. Keywords: square bale, straw crusher, crushing, working parameter optimization, performance test DOI: 10.25165/j.ijabe.20211403.5970 Citation: Zhang J, Feng B, Guo L, Kong L Z, Zhao C, Yu X Z, et al. Performance test and process parameter optimization of 9FF type square bale straw crusher. Int J Agric & Biol Eng, 2021; 14(3): 232–240.

Optimization of the electrolytic polishing parameters of intravascular stent based on the orthogonal test method

Horizontal well drilling is a highly effective way to develop marine gas hydrate. During the drilling of horizontal wells in the marine gas hydrate layer, hydrate particles and cutting particles will migrate with the drilling fluid in the horizontal annulus. The gravity of cuttings is easy to deposit in the horizontal section, leading to the accumulation of cuttings. Then, a cuttings bed will be formed, which is not beneficial to bring up cuttings and results in the decrease of wellbore purification ability. Then the extended capability of the horizontal well will be restricted and the friction torque of the drilling tool will increase, which may cause blockage of the wellbore in severe cases. Therefore, this paper establishes geometric models of different hole enlargement ways: right-angle expansion, 45-degree angle expansion, and arc expanding. The critical velocity of carrying rock plates are obtained by EDEM and FLUENT coupling simulation in different hydrate abundance, different hydrate-cuttings particle sizes and different drilling fluid density. Then, the effects of hole enlargement way, particle size, hydrate abundance and drilling fluid density on rock carrying capacity are analyzed by utilizing an orthogonal test method. Simulation results show that: the critical flow velocity required for carrying cuttings increases with the increase of the particle size of the hydrate-cuttings particle when the hydrate abundance is constant. The critical flow velocity decreases with the increase of drilling fluid density, the critical flow velocity carrying cuttings decreases with the increase of hydrate abundance when the density of the drilling fluid is constant. Orthogonal test method was used to evaluate the influence of various factors on rock carrying capacity: hydrate-cuttings particle size > hole enlargement way > hydrate abundance > drilling fluid density. This study provides an early technical support for the construction parameter optimization and well safety control of horizontal well exploitation models in a marine natural gas hydrate reservoir.

In this paper, we deal with the reference tracking control problem for Electric Unmanned Vehicles (EUV) equipped with batteries of limited energy capacity. We design a novel control architecture, equipped with a battery manager module, which is capable of avoiding energy shortage by appropriately imposing time-varying upper bounds on the vehicle's maximum acceleration. In particular, we exploit some key properties of the Set-Theoretic Model Predictive Control (ST-MPC) paradigm to couple the reference tracking and the battery shortage problems. First, given a desired path, we off-line design a conservative maximum acceleration profile capable of assuring that the EUV will reach the desired target without incurring into a battery shortage along the path. Then, on-line, by following a receding horizon philosophy and by considering a cost function of interest, we show that the battery manager can improve the acceleration profile by using the current battery's state-of-charge. Moreover, we show that the time-varying acceleration constraints imposed by the battery manager do not affect the recursive feasibility of the used ST-MPC tracking controller. Finally, a simulation example is presented to clarify and show the potential and features of the proposed control framework.

The flow field inside cyclone separator is a kind of complex three-dimensional rotation turbulent flow with two-phase separation phenomenon. In order to optimize the structure and shorten the cycle of research and development, it is very essential to find the appropriate calculation method for the flow field inside cyclone separator. In this article, the internal flow field of tangential inlet cyclone separator was simulated and calculated by adopting different calculation model and different numerical simulation scheme by orthogonal design method. And the result was compared with that of existing experiment to find a reasonable method for the simulation of the flow field inside the cyclone. On the basis of standard k-ε model, the numerical simulation scheme was formulated by the orthogonal test method, through the comparison of results, the best combinations are gained; This research result has certain reference value for cyclone separator design and performance optimization.

The experimental investigations on resistance spot welding of 201 stainless steel are presented. Experiments are carried out to study the influence of spot welding parameters (electrode force, welding current and welding time) on the tensile shear load and the diameter of nugget, based on an orthogonal test and analysis method. The optimum parameters are as follows: electrode force is 3600N, welding current is 6400A and welding time is 8 cycles. The maximum tensile shear force is up to 8920N.The microstructure of spot weld is columnar crystals in the nugget and equiaxed grains around periphery induced by non-equilibrium freezing. And the heat input has great influence on the welding defects which can cause joint quality degradation.

The characteristics of internal combustion engines (hereinafter referred to as ICE) have the following disadvantages: there is a gap between zero and minimum angular velocity, so it is impossible to move out of a state of rest; the dependence of torque on angular velocity is not ideal. They are corrected by the following converters: the first by a clutch or torque converter, and the second by a gearbox or variator. In addition, the ICE characteristics can be partially close themselves to ideal. Electric motors (here in after referred to as motors) of electric vehicles have an ideal characteristic that starts from scratch and has a large zone with a sustainable maximum power. The addition of the drive with the ICE motor in hybrid electric cars solves these problems. The different characteristics of ICE, motors and converters increase the number of possible configurations that affect the characteristics of the supply of power to the wheels. According to the traction characteristics of the car, the indicators of the traction and speed properties of the car are determined: the ability to overcome climbs, maximum acceleration, maximum speed on a horizontal road, acceleration time to a given speed, etc. The last two indicators depend primarily on the maximum power of ice or motor and are important for supercars, while for conventional cars or electric vehicles with close values of maximum speed and acceleration time to a given speed, they mean nothing. The authors propose to evaluate the efficiency of the drive during acceleration with maximum acceleration of the power utilization factor k N 0–100 – the particles from the division of the average value of the realized power on the wheels in the interval of speeds (0; 100) km/h by the maximum power value on the wheels. The characteristics of ICE and motors are given, traction characteristics in power coordinates are calculated – the speed of movement of cars with typical drive configurations, their power utilization coefficients are determined and appropriate conclusions are made. In the future, it is planned to investigate the use of power in more complex drive systems of hybrid cars with the recovery of braking energy.

Background: The method was proposed to optimize the warpage and volume shrinkage of the blade of a plant protection unmanned aerial vehicle (UAV) during injection molding. The influence of molding defects on the geometric parameters of airfoil was analyzed from two aspects of blade geometry structure and molding process based on blade element theory. This paper focuses on reducing the warpage and volume shrinkage of the blade in the production process and improving molding quality through moldflow analysis and calculation. Objective: The purpose of this patent study was to combine injection molding CAE with orthogonal test and response surface method to reduce product warpage and volume shrinkage, improve dimensional accuracy and production efficiency, and combine fluid dynamics simulation experiments to prove the experiment's reliability. Methodology: The optimization method of injection molding process parameters was proposed based on the orthogonal test and response surface method, combining the principles of aerodynamics mathematics and polymer injection molding. The Taguchi experiment was designed with melt temperature injection time and mold temperature pressure holding time as the optimization variable. The Box-Behnken Design (BBD) experiment was designed, and the response surface model was established with Design-Expert software to analyze the mapping relationship between process parameters and warpage and volume shrinkage. Moldflow software was used for flow analysis on the basis of analysis by response surface method, and the deformed parts were analyzed by computational fluid dynamics (CFD) with ANSYS software to prove the reliability of the calculation process. Results: The warpage and volume shrinkage of the product can be significantly reduced based on the orthogonal test and response surface model. The aerodynamic performance of the blade can be improved by optimization injection molding, making the actual production of the blade close to the original design blade model to the greatest extent and reducing the actual production trial and error cost. Conclusion: An optimization method of the injection molding process of the UAV rotor was proposed based on the response surface method and blade element theory. Through the systematic design and optimization of injection molding parameters, the molding quality and performance of the rotor can be improved, which provides a new way to optimize the dynamic components of massproduced UAVs.

Panax notoginseng is grown mainly in Yunnan Province. Under the present high-density planting patterns for the plant, to solve the problems of a high rate of seed damage and the inability to use a traditional single air-blowing metering device, this paper designs a six-row air-blowing centralized precision seed-metering device for P. notoginseng to realize mechanized precision seeding of this species. This paper describes the working principle of the seed-metering device, and the main structural parameters are determined by combining theoretical calculations with simulation analysis. A mechanics model of the seed filling, cleaning and pressing processes of the seed-metering device was constructed. The seeds of P. notoginseng in Yunnan Province were selected as experimental subjects. An experimental study on the seed-metering performance of the seed-metering device was carried out using the quadratic rotation orthogonal combination test method. The outlet pressure of the air nozzle, forward velocity and cone angle of the hole were selected as test factors. Mathematical models of the grain spacing qualified index, miss index, multiple index and the coefficient of variation of the row displacement consistency were established to analyze the order of factors affecting indicators. Through parameter optimization, the optimum combination of parameters was determined as follows: the cone angle of the hole is 50°, the forward velocity is less than 0.73 m/s, and the outlet pressure of the air nozzle is 0.32-0.52 kPa. The qualified index of grain spacing is higher than 94%, the miss index is less than 3%, the multiple index is less than 5%, and the coefficient of variation of the row displacement consistency is less than 5%. The test results are essentially consistent with the optimization results. The metering device meets the requirements of precision seeding of P. notoginseng. This study provides a basis for the design of a six-row air-blowing centralized precision seed-metering device for P. notoginseng. Keywords: Panax notoginseng, air blowing, seed-metering device, optimization design, air distribution mechanism DOI: 10.25165/j.ijabe.20201302.5161 Citation: Lai Q H, Sun K, Yu Q X, Qin W. Design and experiment of a six-row air-blowing centralized precision seed-metering device for Panax notoginseng. Int J Agric & Biol Eng, 2020; 13(2): 111–122.

Nine healthy subjects performed 2D pointing movements using a joystick that controlled a screen cursor. Continuous visual feedback was provided until movement completion. Three variables were systematically manipulated: (1) target distance, (2) target size and (3) target direction. A four-way factorial ANOVA was used to analyze the effects of these fixed factors and of the random factor of subject on several movement parameters. Movement time increased with increasing distance and decreasing target size and as predicted from Fitts' law. The target direction did not affect movement time. In contrast the direction, distance and size of the target significantly affected the movement time until the first zero crossing on the speed record reflecting the time to bring the arm into the vicinity of the target. Movements on the lateral axis of the horizontal plane (horizontal movements) resulted in a decrease in initial movement time compared to movements on the anterior axis of the horizontal plane (vertical movements). A significant effect of target distance and direction but not target size was observed for the magnitude of maximum acceleration, maximum speed and maximum deceleration. Horizontal movements had a larger maximum acceleration, speed and deceleration. Furthermore the maximum speed and deceleration occurred earlier in time for these horizontal movements. Finally the number of secondary peaks on the speed record increased with decreasing target size and was not affected by the target distance or target direction. In conclusion our results indicate that different movement parameters are affected by target distance, size and direction. The crucial distinction was between parameters affected by target size and direction. These parameters did not overlap. Target direction affects the first part of movement execution while target size affects the final part of movement execution. Thus a clear segmentation of movement execution in two phases is supported by these results. The implications of these results for theoretical models of speed-accuracy trade-off are discussed.