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101.
针对目前板栗脱壳过程中主要依靠手工剥壳,手指极易被板栗刺壳上坚硬的刺刺伤,以及劳动强度大、生产效率低的问题,设计了一种新型的自动板栗脱壳机。该机采用胶皮与螺纹钢揉挤的方式将板栗刺与板栗米分开,同时采用鼓风机搭配输送带的方式进行分离。实际测试结果表明,该机采用的脱壳方式和分离方式新颖,能最大限度地将板栗米与板栗刺剥离,且能实现两者的自动分离,对于减轻栗农劳动强度,缩短栗子从采摘到上市的时间发挥了极大作用,值得进一步推广普及。 相似文献
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Jorge Torres-Sánchez Francisco Javier Mesas-Carrascosa Fernando Pérez-Porras Francisca López-Granados 《Pest management science》2023,79(2):645-654
BACKGROUND
Ecballium elaterium (common name: squirting cucumber) is an emerging weed problem in hedgerow or superintensive olive groves under no tillage. It colonizes the inter-row area infesting the natural or sown cover crops, and is considered a hard-to-control weed. Research in other woody crops has shown E. elaterium has a patchy distribution, which makes this weed susceptible to design a site-specific control strategy only addressed to E. elaterium patches. Therefore, the aim of this work was to develop a methodology based on the analysis of imagery acquired with an uncrewed aerial vehicle (UAV) to detect and map E. elaterium infestations in hedgerow olive orchards.RESULTS
The study was conducted in two superintensive olive orchards, and the images were taken using a UAV equipped with an RGB sensor. Flights were conducted on two dates: in May, when there were various weeds infesting the orchard, and in September, when E. elaterium was the only infesting weed. UAV-orthomosaics in the first scenario were classified using random forest models, and the orthomosaics from September with E. elaterium as the only weed, were analyzed using an unsupervised algorithm. In both cases, the overall accuracies were over 0.85, and the producer's accuracies for E. elaterium ranged between 0.74 and 1.00.CONCLUSION
These results allow the design of a site-specific and efficient herbicide control protocol which would represent a step forward in sustainable weed management. The development of these algorithms in free and open-source software fosters their application in small and medium farms. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献105.
杂交水稻制种不同于水稻栽培、其结实由柱头外露结实和非柱头外露结实两部分构成;空壳中90%以上是由于没有授粉受精造成的:90%以上的受精拉都能正常发育结实。柱头外露率和受精率与结实率呈显著正相关。后期施肥、父本大龄秧和机械授粉能有效地提高柱头外露率、花遇优度和结实率及制种产量。 相似文献
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Operational Deflection Shapes of large scale electromechanical system can be ex-tracted directly from multipoints response of the operating system by using of the modal shape analy-sis method. Thev can be used for engineers evaluating the practical dynamic beavior of the largescale elecltromechanical system,checking the existence of local reso,iance of the Stibsystem. and in-dentifying the wcakened positions of the rigidity of structure, In this paper the method of measuringand extracting the operational deflection shal1e of the electromecha nical system is given and theavailability of operational deflection shape is proved by analyzing the actual vibration of a large ex-haust fan system as an example. 相似文献
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Wang Bingle Song Liquan 《保鲜与加工》1988,(2)
This paper presents a new method by using mass and acceleration parameters for balancing inertial force of mechanism. Compared with other balance methods, this one is simple, clear and superior in regularity when the balancing equation of complex mechanism is established, and its solving procedure is also easy. The new methcd is convenient to learn and use as well as convenient to program. 相似文献
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It is difficult to measure the geometric quantity of small parts in finishing, assembling and measuring, because it's easy to break the workpieces' surface and alter their position by means of traditional contact measuring methods.There are some non contact measurers, such as,light feeler pin and interference microscope etc., because of it's high price and strict working conditions,so it's difficult to promote them in widely use. Precision measurement system based on machine vision has the advantages of non contact measuring as well as high performance and low price. Some problems, such as light source, algorithm of edge fitting, auto focusing,are discussed. 相似文献
110.