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Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences 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 Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department 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 Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department 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 Clean Coal Technology is the property of Clean Coal 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.)

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department 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 Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department 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 Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department 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 Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering 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 Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department 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 Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department 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 this paper, the combination of finite element modeling and experiment was used to study the effects of different vibration parameters such as vibration time (A), amplitude (B) of the vibration excitation point on apricot tree vibration and vibration frequency (C), and optimize the performance of forest fruit vibration harvesting prototype. The effects of different vibration parameters on the vibration detection points of apricot trees were analyzed by vibration response test. The response analysis of apricot tree free modal vibration using ANSYS Workbench software showed that apricot trees had typical free modal responses at 15, 26, 30 and 40 orders, the corresponding frequencies were 5.5, 10.5, 15.1, and 29.3 Hz, respectively; and the maximum displacement deformation of fruit trees was 286.5, 261.9, 267.2, and 273.5 mm, respectively. The typical free modal cloud image analysis showed that the typical free modalities of the 15th and 26th orders were higher in the terminal end responsiveness of the apricot branches. The 30th order fruit tree had a high overall response consistency, and the apricot tree had the largest deformation response at the end; at the 40th order of 29.3 Hz, some branches of the fruit trees were severely deformed, and the overall structure of the tree was easily destroyed. The optimal response frequency of apricot tree vibration harvesting ranged from 0 to 20 Hz. The harmonic response analysis showed that in the optimal frequency range, the acceleration of the same position increased with the increase of the excitation amplitude at the same frequency, but the overall variation of the vibration curve was consistent with the trend; When the amplitude of the vibration excitation point of the apricot tree was 5, 10 and 15 mm, at the same frequency, as the excitation amplitude increased, the acceleration at the same position increased, but the overall variation of the vibration curve was consistent with the trend. The three-factor and three-level vibration response tests were conducted to study the effects of vibration time, vibration frequency and excitation point amplitude on the acceleration of three different detection points. The multivariate regression analysis of variance showed that the accelerations P1 and P2 of detection points 1 and 2 were less than 0.000 1, the overall model was highly significant (P<0.01), and the model regression terms B and C were significant. The acceleration P3 of the detection point 3 was 0.000 1, and the overall model was highly significant (P<0.01), except that the acceleration P3 value of the detection point 3 of the model regression terms AB, AC and A2 was not significant (P>0.05), and other regression terms were significant (P<0.05). The factors which affected the acceleration of the detection points 1 and 2 were the same as the amplitude of the excitation point, vibration frequency and vibration time. The order of the magnitude of the acceleration affecting the detection point 3 was the vibration time, the amplitude of the excitation point, and the vibration frequency. Through the response equations of the three detection points, the coefficient of determination R2 of the regression equations from the bottom to the top three detection points were 0.906 7, 0.879 3 and 0.973 3, respectively. Using the Design-Expert 10.0.3 software to optimize the detection point response equation, the optimal vibration recovery parameter combination was that the vibration time was 7.207 s, the vibration frequency was 15 Hz, and the amplitude of the excitation point was 10 mm. The verification test showed that the acceleration from the bottom to the top of each detection point was 10.4, 10.2 and 9.3 g, which was similar to the optimized value. These conclusions can provide design and theoretical basis for the design of mechanical parameters of apricot vibration harvesting. [ABSTRACT FROM AUTHOR]

In order to study the transient response state and movement state of apricot fruit during different stages of exfoliation, a dynamic model of apricot fruit-fruit branch double pendulum hanging on a single long stem branch according to the actual growth of apricot fruit was established in this paper. The apricot fruit-stem separation conditions were analyzed theoretically, and the physical parameters of Kumai apricot fruit at ripening stage were measured. The whole forced vibration process of the target fruitS was recorded by using 2 high-speed cameras with same specifications perpendicular to the xoz plane and the yoz plane, and the relevant datas such as shedding time, speed, and acceleration were obtained. Theoretical analysis and experiments showed that the apricot fruit-fruit branch double pendulum system mainly shows 3 kinds of motion states: fruit branch drives fruit to swing, fruit branch drives fruit to twist and fruit swing. The average weight of the ripe fruit of Kumari apricot was 14.26 g, the average external dimensions were 28.84 mm in length, 27.93 mm in width, and 27.83 mm in thickness; the average surface hardness of mature fruit was 9.17 kg/cm2; and the average connection force of ripe fruit-stem is 2.923 N. Based on the measured spatial coordinates of the fruit in the xoz and yoz planes and Phantom Camera Control 3.1 high-speed video control software analysis, the whole spatial motion track of apricot fruit is nearly elliptical from vibration to shedding, the total time from vibration to shedding of target fruit was 0.322 s, and the maximum speed of the relative static origin of apricot fruit was 0.112 and 0.166 m/s when be dropped in spatial planes xoz and yoz. The instantaneous speed of the apricot fruit before shedding was 1.53 and 1.359 m/s, respectively, and the acceleration was 765 and 679.98 m/s2, respectively. Using MATLAB software, the velocity data of fruit in different planes xoz and yoz were compared with the Fourier fitting curves of velocity and time relative to stationary origin, and the fitting curve of the speed of apricot fruit during vibration shedding and the corresponding function were obtained. R2 value of the fitting function were 0.970 4 and 0.986. Through analyzing the speed function curve, the process of fruit vibration shedding could be divided into 3 periods: 0 to 0.148 s, 0.148 to 0.248 s, and 0.248 to 0.322 s. In the third stage, the fruit has already fallen off before it reaches the full cycle. To ensure the accuracy of the analysis, the analysis of the velocity function in the first 2 stages with complete vibration period showed that: in the xoz plane, the velocity fitting function R2 of the first 2 stages are 0.965 2 and 0.952 5, respectively, the speed change period is 0.15 s and the function amplitude is 0.021 m/s; the velocity fitting function R2 in the first 2 stages of the yoz plane is 0.954 5 and 0.981 1, respectively, and the speed change period is 0.13 s, the amplitude of the second stage function is twice that of the first stage, which is 0.054 and 0.027 m/s, respectively. The vibration cycle of the apricot fruit-fruit branch double pendulum system is close to the period of the excitation cycle. According to the calculation of the fruit weight of mature apricot, the shedding force components produced by acceleration on each plane were 11.22 and 9.7 N respectively, both of which were greater than the average connected force between mature apricot fruit and stalk. Based on the above characteristics of fruit vibratory shedding, this study can provide a theoretical basis for clarifying the shedding mechanism during fruit harvesting, optimizing the design parameters of apricot vibrating harvester, and improving the fruit recovery rate. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering 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.)