Study and Experiment on a Wheat Precision Seeding Robot

Aiming at the problems of high grain entrainment loss rate and impurity rate of traditional horizontal axial-flow combine harvesters, a horizontal axial-flow threshing-separating device with coaxial differential threshing drum, conical cleaning fan, double-layer vibrating screen and spiral plate-tooth re-thresher is designed. Meanwhile, a test-bed with a feeding rate of 2 kg/s is designed to improve the device performance. The test through quadratic orthogonal rotation combination design method is used to inspect the effects of the differential drumspeed combination, conical fan blade taper, and length ratio of the high and low speed sections of the differential drum on the loss rate, crushing rate , impurity rate and threshing power consumption. The regression mathematical models of the loss rate, crushing rate, impurity content and threshing power consumption are established, and the multi-objective optimization calculation of the regression mathematical model is carried out by using MATLAB optimization toolbox. The results show that the order of the three factors affecting the loss rate and impurity content of the horizontal axial-flow threshing-separating device is the differential drumspeed combination, the conical fan bladetaper, and the length ratio of high and low speed sections of the differential drum. The field test results show that the performance index of the horizontal axial-flow separation device is better than the requirements of the national standard.

Mung bean (Vigna radiata L.) is an important edible bean in the human diet worldwide. However, its growth, development, and yield may be restricted or limited by insufficient or unbalanced nitrogen (N), phosphorus (P), and potassium (K) fertilization. Despite this, there are few long-term studies of the effects of varying levels of N, P, and K combined fertilizers and the optimal fertilization for improving mung bean yield and quality. This study was conducted to optimize the fertilization strategies for high yield and to improve yield components (pods per plant, seeds per pod, and 100-seed weight) in the Bailv9 mung bean cultivar, 23 treatments were tested in 2013–2015, using a three-factor (N, P, and K fertilizers), five-level quadratic orthogonal rotation combination design. Our studies showed that, the N, P, and K fertilizers significantly influenced the pods per plant and yield, which increased and then decreased with the increasing N, P, and K fertilizers. The 100-seed weight was significantly affected by the N and P fertilization, and it was increased consistently with the increasing N fertilizer, and decreased significantly with the increasing P fertilizer. Whereas, the seeds per pod significantly decreased with the increasing N and K fertilizers, and the P fertilizer had no significant effect on it. The NP interaction had a significant effect on yield and pods per plant at high N levels, while the NK interaction had a significant but opposite effect on yield at low N levels. The optimal fertilization conditions to obtain yield >2,141.69 kg ha-1 were 34.38–42.62 kg ha-1 N, 17.55–21.70 kg ha-1 P2O5, and 53.23–67.29 kg ha-1 K2O. Moreover, the optimal N, P, and K fertilization interval to achieve pods per plant > 23.41 and the optimal N fertilization to achieve a 100-seed weight > 6.58 g intersected with the interval for yield, but the seeds per pod did not. The fertilizer ratio for the maximum yield was N:P2O5:K2O = 1:0.5:1.59. Following three years experimentation, the optimal fertilization measures were validated in 2016–2017, the results indicated that yield increased by 19.6% than that obtained using conventional fertilization. The results of this study provide a theoretical basis and technical guidance for high-yield mung bean cultivation using the optimal fertilization measures.

In the paper, the analysis of wave scattering on a system of two soundproof spheres was carried out using the orthogonal central compositional design method. The main objectives of the work are to determine the main parameters, the change of which significantly affects on the whole system; to determine the variable parameter values of the system, at which the loss functions (the total scattering cross section and the normalized pressure at a fixed point) take the minimum and maximum values, and to study the system at optimal parameter values. The orthogonal compositional design method is implemented for a three-factor computational experiment, where three main parameters of the system were selected as factors: the wave radius, the ratio of the sphere radii, and the distance between the sphere centers. For the obtained regression equation, the significance of the coefficients was checked using Student’s t-test and the adequacy of the model using Fisher’s F-test. It was found that in the case of a spherical wave from a monopole radiation source, the nonlinear influence of the factors is more pronounced than in the case of a plane wave; normal pressure calculated at a fixed point is insensitive to changes in parameters in the case of a plane wave, as well as in the case of a monopole radiation source for small values of the sphere surface complex conductivity; the total scattering cross section is highly sensitive in the case of a system with ideally rigid spheres; the highest and lowest values of the loss functions are achieved at the boundary of the three-dimensional parametric region of factors changes. Pressure distribution diagrams were constructed, which made it possible to determine the zones of high or low pressure for the found optimal values of the factors.

Shale oil is mainly extracted by fracturing. However, it is difficult to determine the optimum construction parameters to obtain maximum productivity. In this paper, a fuzzy comprehensive production evaluation model for fractured shale oil horizontal wells based on random forest algorithm and coordinated principal component analysis is proposed. The fracturing parameters of the target wells are optimized by combining this model with an orthogonal experimental design. The random forest algorithm was used to calculate the importance of data sample factors. The main controlling factors of the production of fractured horizontal wells in shale oil were obtained. To reduce the noise of the sample data, principal component analysis was used to reduce the dimensions of the main control factors. Furthermore, the random forest algorithm was used to determine the weight of the principal components after reducing the dimensionality. The membership function of the main control factors after reducing dimensionality was established by combining the fuzzy statistics and assignment methods. In addition, the membership matrix of the effect prediction of fractured horizontal wells in shale oil was determined. The fuzzy comprehensive evaluation method is used to score and evaluate the effect of fractured horizontal wells. Combined with the orthogonal experimental design method, the optimized parameter design of a fractured horizontal well considering the comprehensive action of multiple parameters is realized. After construction according to the optimized parameters, production following fracturing increases significantly. This verifies the rationality of the optimization method that is proposed in this paper.

AlGaN and AlN, III-nitride semiconductors distinguished by wide bandgaps, strong polarization, and exceptional chemical stability, hold substantial potential for applications in high power and high frequency electronics, high temperature sensors, and optoelectronic devices. These materials thus serve as a cornerstone for next generation technologies. Metal organic chemical vapor deposition (MOCVD) is the preeminent technique for synthesizing high quality AlGaN and AlN films, with vertical showerhead reactors being widely employed due to their efficiency and stability. This study focuses on optimizing the arrangement of heating wires within an MOCVD reaction chamber. Using a quadratic regression orthogonal rotation combination design, we investigated the effects of heating wire width and spacing on temperature distribution within the reaction cavity. By univariate analysis and quadratic regression modeling, we identified the optimal combination of heating wire width and spacing to achieve uniform and stable temperature distribution. Our results show that the heating wire gap has the most significant impact on the average temperature of the mixing chamber, followed by the heating wire width and their interaction effects. The optimized heating wire arrangement markedly enhances the average temperature of the reaction chamber, thereby providing an improved thermal environment for the growth of high quality AlN films. This research offers both theoretical insights and practical guidance for the design and optimization of MOCVD reactors.

The last decade has witnessed a great interest on the application of evolutionary algorithms, such as genetic algorithm (GA), particle swarm optimization (PSO) and gene expression programming (GEP), for optimization problems. This paper presents a hybrid algorithm by combining the GEP algorithm and the orthogonal design method. A multiple-parent crossover operator is introduced for the chromosome reproduction using the orthogonal design method. In addition, an evolutionary stable strategy is also employed to maintain the population diversity during the evolution. The efficiency of the proposed algorithm is evaluated using three benchmark problems. The results demonstrate that the proposed hybrid algorithm has a better generalization ability compared to conventional algorithms.

On-line conversion and determination of artemisinin and its kinetic parameters using orthogonal design by coupling of flow injection with capillary electrophoresis

The quality of smooth blasting including the volume of over‐/underbreak and blasting‐induced damage of surrounding rocks has been extensively considered to be highly correlated to both the cost and advancement rate of rock tunnelling excavated by the drill‐blast method. A general control strategy for smooth blasting is too difficult to be available due to the uncertainties and complexity of rock masses, as well as the varying blasting operations. As prerequisite for the evaluation of the blasting quality, effective identification of the influential factors affecting smooth blasting usually plays a significant role in the improvement of smooth blasting design. Compared to the expensive and time‐consuming experiments including physical modelling and field tests, numerical modelling, as a cost‐efficient approach, offers an attractive alternative to investigate the influential factors in terms of weight, which might be more applicable and reliable for the optimization of smooth blasting parameters. In this case, the dominant factors and secondary factors can be quantitatively identified. Considering the dominant factors often orient the development of things; in this work, a numerical‐based approach was proposed to quantitatively identify the dominant factors influencing the quality of smooth blasting. Proposed 3‐dimensional blasting modelling was based on LS‐DYNA to simulate the occurrence of smooth blasting in rock masses, and the erosion algorithm was also employed to determine the fracturing of jointed rocks. The orthogonal experimental design method was utilized to optimize the experimental arrangement. Seven factors with 4 levels including the perimeter hole spacing, line of least resistance, charge concentration, charging explosive, type of rock mass, detonation velocity, and drilling deviation were taken into account. The geological setting and project background of a real rock tunnel served for the Chengdu‐Chongqing high‐speed railway were selected as the site conditions to perform the numerical investigation. Calculated area and distance of overbreak as the observed parameters indicating the quality of smooth blasting were utilized to determine sensitivities of factors based on the range analysis of orthogonal experiments. The results suggested that the type of rock mass has the greatest influence on the blasting quality, whereas the charge concentration and detonation velocity can be considered as the secondary factors under the specific site conditions. The proposed numerical approach for assessing influential factors of quality of smooth blasting under specified geological conditions is expected to improve the parameter design and operation of smooth blasting in practical applications.

Orthogonal design method (ODM) is widely used in real world application while it is not used for antenna design yet. It is employed to optimize roughly designed antenna in this paper. The geometrical factors of the antenna are relaxed within specific region and each factor is divided into some levels, and the performance of the antenna is constructed as objective. Then the ODM samples small number of antennas over the relaxed space and finds a prospective antenna. In an experiment of designing ST5 satellite miniantenna, we first get a roughly evolved antenna. The reason why we evolve roughly is because the evolving is time consuming even if numerical electromagnetics code 2 (NEC2) is employed (NEC2 source code is openly available and is fast in wire antenna simulation but not much feasible). Then the ODM method is employed to locally optimize the antenna with HFSS (HFSS is a commercial and feasible electromagnetics simulation software). The result shows the ODM optimizes successfully the roughly evolved antenna.

A high specific speed centrifugal pump is used in the situation of large flow and low head. Centrifugal pump parameters need to be optimized in order to raise its head and efficiency under off-design conditions. In this study, the orthogonal experiment design method is adopted to optimize the performance of centrifugal pump basing on three parameters, namely, blade outlet width b2, blade outlet angle β2 and blade wrap angle φ. First, the three-dimensional model of the centrifugal pump is established by CFturbo and SolidWorks. Then nine different schemes are designed by using orthogonal table, and numerical simulation is carried out in CFX15.0. The final optimized combination of parameters is b2 = 24 mm, β2 = 24°, φ = 112°. Under the design condition, the head and efficiency of the optimized centrifugal pump are appropriately improved, the increments of which are 0.74 m and 0.48%, respectively. However, the efficiency considerably increases at high flow rates, with an increase of 6.9% at 1.5 Qd. The anti-cavitation performance of the optimized centrifugal pump is also better than the original pump. The results in this paper can provide references for parameter selection (b2, β2, φ) in the centrifugal pump design.

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.

With the increase of power consumption and running speed, the junction temperature of three-dimensional stacked memory devices has increased. It eventually leads to chip overheating and may cause device failures. It is essential to analyze and optimize the thermal performance of the package. In this paper, the finite element analysis method is used to study the influence of the package module on the chip junction temperature and thermal resistance for the typical six-layer stacked memory chip packaging structure. The main influencing factors are investigated. In addition, the thermal characteristics of the stacked packaging structure are optimized by using the orthogonal experimental design method. After further optimization, the junction temperature decreases by 7.17% and the thermal resistance decreases by 11.59%.

In order to study the sensitivity of factors affecting the homogeneous building slope stability, the orthogonal test design method and shear strength reduction finite element method were used. The stability safety factor of the slope was used as the analysis index, and the range analysis of results of 18 cases were carried out. The results show that the order of sensitivity of slope stability factors is: internal friction angle, slope height, cohesion, slope angle, bulk density, elastic modulus, Poisson's ratio. The analysis results have reference significance for the design and construction of building slope projects.

Use of an orthogonal design method to study two-stage chemical carcinogenesis in BALB/3T3 cells.

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.