Precision planting is one key point of precision agriculture.A doorframe type swing seedling pick-up device for the automatic precise field transplanter was designed and tested in a laboratory.The seedling device coul...Precision planting is one key point of precision agriculture.A doorframe type swing seedling pick-up device for the automatic precise field transplanter was designed and tested in a laboratory.The seedling device could automatically extract seedlings from growing trays,transfer them,and release them into the planting unit where they were to be precisely transplanted into the ground.It consisted of a path manipulator and two grippers.The path manipulator for seedling extraction was constructed with creative design ofⅡ-type mechanism combination in series.It consisted of an oscillating guide linkage mechanism and a grooved globoidal cam mechanism.According to the planned seedling pick-up trajectory,the design of the path manipulator for seedling extraction was finished with a set of the closed loop vector equation.The gripper was a pincette-type mechanism using the pick-up pins to penetrate into the root mass for seedling extraction.It consisted of multiple pick-up pins,U-type pull rod,shaft,stop block,compression spring and frame.The mechanical dimensions of the gripper were determined by the tray size and plant characteristic with a set of rectangular equations and the boundary constraint conditions.The final gripper was developed on the basis of cultural practice for vegetable seedling in China.A prototype of the seedling pick-up device was constructed to examine whether its working efficacy was satisfactory or not.According to the analysis on the work process,the seedling pick-up device could precisely complete a work cycle of approaching,penetrating,extracting,transferring,erecting and discharging a seedling.Taking pepper seedlings,tomato seedlings and cucumber seedlings as the transplanting objects,the performance tests were conducted to evaluate the practicality and adaptability of the pick-up device.The laboratory evaluation showed that the pick-up device equipped with two grippers could extract 70 seedlings per minute with an average success ratio of 90.49%.The quality of extracting seedlings was satisfactory.展开更多
清/浊/静音判决(UVS)是语音压缩、合成以及识别中的一个重要参数。为了解决传统判决方法训练过程复杂,导致语音编码效率低的问题,给出一种无训练过程的判决方法。提取基于循环平均幅度差的特征参量,利用判决参数间的相关性,自适应调整阈...清/浊/静音判决(UVS)是语音压缩、合成以及识别中的一个重要参数。为了解决传统判决方法训练过程复杂,导致语音编码效率低的问题,给出一种无训练过程的判决方法。提取基于循环平均幅度差的特征参量,利用判决参数间的相关性,自适应调整阈值,实现清/浊/静音判决。该判决方法具有很好的抗噪声干扰能力,有效提高判决的准确率。测试结果表明:该算法简化了清/浊/静音判决的计算量,清音误判率降低了10%,浊音误判率保持在4%以内;将该算法应用于低速率语音编码方案MELP(mixed excitation linear prediction)0.6 kbps的清浊音判决中,解码后的合成语音质量优于原始MELP编码方案,PESQ分数提高0.3,具有较好的可懂度和自然度。展开更多
基金National Natural Science Foundation of China(51475216)National Science&Technology Pillar Program during the Twelfth Five-year Plan Period(2013BAD08B03)+3 种基金Jiangsu Province Science and Technology Support Program of China(BE2012381&BE2014373)Priority Academic Program Development of Jiangsu Higher Education Institutions(SFE(2014)37)Jiangsu Province Synergistic Innovation Center Program of Modern Agricultural Equipment and Technology(NZXT02201402)Fund for Independent Innovation of the Jiangsu Province Agricultural Science and Technology(CX(15)1033-5)
文摘Precision planting is one key point of precision agriculture.A doorframe type swing seedling pick-up device for the automatic precise field transplanter was designed and tested in a laboratory.The seedling device could automatically extract seedlings from growing trays,transfer them,and release them into the planting unit where they were to be precisely transplanted into the ground.It consisted of a path manipulator and two grippers.The path manipulator for seedling extraction was constructed with creative design ofⅡ-type mechanism combination in series.It consisted of an oscillating guide linkage mechanism and a grooved globoidal cam mechanism.According to the planned seedling pick-up trajectory,the design of the path manipulator for seedling extraction was finished with a set of the closed loop vector equation.The gripper was a pincette-type mechanism using the pick-up pins to penetrate into the root mass for seedling extraction.It consisted of multiple pick-up pins,U-type pull rod,shaft,stop block,compression spring and frame.The mechanical dimensions of the gripper were determined by the tray size and plant characteristic with a set of rectangular equations and the boundary constraint conditions.The final gripper was developed on the basis of cultural practice for vegetable seedling in China.A prototype of the seedling pick-up device was constructed to examine whether its working efficacy was satisfactory or not.According to the analysis on the work process,the seedling pick-up device could precisely complete a work cycle of approaching,penetrating,extracting,transferring,erecting and discharging a seedling.Taking pepper seedlings,tomato seedlings and cucumber seedlings as the transplanting objects,the performance tests were conducted to evaluate the practicality and adaptability of the pick-up device.The laboratory evaluation showed that the pick-up device equipped with two grippers could extract 70 seedlings per minute with an average success ratio of 90.49%.The quality of extracting seedlings was satisfactory.
文摘清/浊/静音判决(UVS)是语音压缩、合成以及识别中的一个重要参数。为了解决传统判决方法训练过程复杂,导致语音编码效率低的问题,给出一种无训练过程的判决方法。提取基于循环平均幅度差的特征参量,利用判决参数间的相关性,自适应调整阈值,实现清/浊/静音判决。该判决方法具有很好的抗噪声干扰能力,有效提高判决的准确率。测试结果表明:该算法简化了清/浊/静音判决的计算量,清音误判率降低了10%,浊音误判率保持在4%以内;将该算法应用于低速率语音编码方案MELP(mixed excitation linear prediction)0.6 kbps的清浊音判决中,解码后的合成语音质量优于原始MELP编码方案,PESQ分数提高0.3,具有较好的可懂度和自然度。