Maize harvesting is one of the most important filed operations of maize production.As the accelerating development of maize industry,mechanized maize harvesting is widely accepted and used by farmers in the world.Acco...Maize harvesting is one of the most important filed operations of maize production.As the accelerating development of maize industry,mechanized maize harvesting is widely accepted and used by farmers in the world.According to the harvesting methods,maize harvesters could be classified into two types,one is maize-for-grain harvesters,including pickers and grain harvesters,the other is whole plant harvesters,including forage harvesters and combined grain-stover harvesters.Structure characteristics,appropriate areas and relative technologies of those harvesters are described in this paper,i.e.,pickers are suitable for multi-crop areas,Grain harvesters are mainly for one-crop areas when grain moisture content is lower than 25%,combined grain-stover harvesters are applicable in agro-pastoral ecotone,and forage harvesters are capable in large-scaled animal husbandry farming areas where large amount of silage are required.Meanwhile,the future development trend of the different harvesters is predicted.Big horsepower engines,enhanced working efficiency,automation and intelligence are required by large scaled farms.As maize breeding development,more varieties that are suitable for grain harvesting are put into practice,so grain combine harvesters will be popular in future.展开更多
We present a high-resolution seismic catalog for the 2021 M_(S)6.4/M_(W)6.1 Yangbi sequence.The catalog has a time range of 2021-05-01 to 2021-05-28,and contains~8,000 well located events.It captures the features of t...We present a high-resolution seismic catalog for the 2021 M_(S)6.4/M_(W)6.1 Yangbi sequence.The catalog has a time range of 2021-05-01 to 2021-05-28,and contains~8,000 well located events.It captures the features of the whole foreshock sequence and the early aftershocks.We designed a detection strategy incorporating both an artificial intelligent(AI)picker and a matched filter algorithm.Here,we adopt a hybrid AI method incorporating convolutional and recurrent neural network(CNN&RNN)for event detection and phase picking respectively(i.e.CERP),a light-weight AI picker that can be trained with small volume of data.CERP is first trained with detections from a STA/LTA and Kurtosis-based method called PAL,and then construct a rather complete template set of~4,000 events.Finally,the matched filter algorithm MESS augments the initial detections and measures differential travel times with cross-correlation,which finally results in precise relocation.This process gives 9,026 detections,among which 7,943 events can be well relocated.The catalog shows as expected power-law distribution of frequency magnitude and reveals detailed pattern of seismicity evolution.The main features are:(1)the foreshock sequence images simple fault geometry with consistent strike,but also show a variable event depth along strike;(2)the mainshock ruptures the same fault of the foreshock sequence and activate conjugate faults further to the southeast;(3)complex seismicity are developed in the post-seismic period,indicating complex triggering mechanisms.Thus,our catalog provides a reliable basis for further investigations,such as b-value studies,rupture process,and triggering relations.展开更多
To solve the problems of excessive soil lumps,broken branches and seedlings in pods and difficulty in removing impurities in the harvested pods of peanuts in the hilly areas of southern China,which is due to the high ...To solve the problems of excessive soil lumps,broken branches and seedlings in pods and difficulty in removing impurities in the harvested pods of peanuts in the hilly areas of southern China,which is due to the high soil viscosity and easy hardening,and to improve the soil removal effect of the peanut half-feed pod picker in hilly areas of China,this article designed a half-feed peanut-cleaning picker suitable for southern clay hilly areas and provided a detailed introduction to the overall structure,working principle,and adjustment methods of various operating parameters.Through field measurement experiments,the influencing factors and laws of soil removal performance indicators,such as the comprehensive soil removal rate and POD drop rate,were studied.The results showed that the comprehensive soil removal rate gradually increased with increasing soil patting frequency,soil patting amplitude,and picking roller speed,first increased and then decreased with increasing picking roller gap and gradually decreased with increasing soil patting plate gap and clamping conveyor chain speed.The comprehensive soil removal rate of the soil patting plate using the opposite patting method was greater than that of the swinging patting method.The soil removal pod drop rate increased gradually with increasing soil patting frequency and amplitude and decreased with increasing soil patting plate gap and clamping conveyor chain speed.The soil removal pod drop rate of the soil patting plate using swing patting was lower than that using the opposite patting method.The speed and gap of the picking roller had no effect on the soil removal pod drop rate.The frequency,amplitude,form,and gap of the soil patting plate had extremely significant impacts on the rate of decrease in the number of soil removal pod drop rate.The clamping conveyor chain speed had a significant impact,while the speed and gap of the picking roller had no significant impact.The influence of all factors on the comprehensive soil removal rate was extremely significant.展开更多
基金the National Natural Science Foundation of China(51405495)the National Industry System of Maize Technology(CARS-02)the Soil-Machine-Plant key laboratory of Ministry of Agriculture of China.
文摘Maize harvesting is one of the most important filed operations of maize production.As the accelerating development of maize industry,mechanized maize harvesting is widely accepted and used by farmers in the world.According to the harvesting methods,maize harvesters could be classified into two types,one is maize-for-grain harvesters,including pickers and grain harvesters,the other is whole plant harvesters,including forage harvesters and combined grain-stover harvesters.Structure characteristics,appropriate areas and relative technologies of those harvesters are described in this paper,i.e.,pickers are suitable for multi-crop areas,Grain harvesters are mainly for one-crop areas when grain moisture content is lower than 25%,combined grain-stover harvesters are applicable in agro-pastoral ecotone,and forage harvesters are capable in large-scaled animal husbandry farming areas where large amount of silage are required.Meanwhile,the future development trend of the different harvesters is predicted.Big horsepower engines,enhanced working efficiency,automation and intelligence are required by large scaled farms.As maize breeding development,more varieties that are suitable for grain harvesting are put into practice,so grain combine harvesters will be popular in future.
基金supported jointly by National Key R&D Program of China(No.2018YFC1503400)National Natural Science Foundation of China projects(Nos.41774067,U2039204,and 42074046)+2 种基金Science for Earthquake Resilience(No.XH20082Y)US National Science Foundation(No.1941719)University of California at Riverside.
文摘We present a high-resolution seismic catalog for the 2021 M_(S)6.4/M_(W)6.1 Yangbi sequence.The catalog has a time range of 2021-05-01 to 2021-05-28,and contains~8,000 well located events.It captures the features of the whole foreshock sequence and the early aftershocks.We designed a detection strategy incorporating both an artificial intelligent(AI)picker and a matched filter algorithm.Here,we adopt a hybrid AI method incorporating convolutional and recurrent neural network(CNN&RNN)for event detection and phase picking respectively(i.e.CERP),a light-weight AI picker that can be trained with small volume of data.CERP is first trained with detections from a STA/LTA and Kurtosis-based method called PAL,and then construct a rather complete template set of~4,000 events.Finally,the matched filter algorithm MESS augments the initial detections and measures differential travel times with cross-correlation,which finally results in precise relocation.This process gives 9,026 detections,among which 7,943 events can be well relocated.The catalog shows as expected power-law distribution of frequency magnitude and reveals detailed pattern of seismicity evolution.The main features are:(1)the foreshock sequence images simple fault geometry with consistent strike,but also show a variable event depth along strike;(2)the mainshock ruptures the same fault of the foreshock sequence and activate conjugate faults further to the southeast;(3)complex seismicity are developed in the post-seismic period,indicating complex triggering mechanisms.Thus,our catalog provides a reliable basis for further investigations,such as b-value studies,rupture process,and triggering relations.
基金supported by the Jiangsu Agricultural Science and Technology Innovation Fund(Grant No.CX(23)3028)National Natural Science Foundation of China(Grant No.52105263)+2 种基金Key Laboratory of Modern Agricultural Intelligent Equipment in South China,Ministry of Agriculture and Rural Affairs,China(Grant No.HNZJ202201)Key Laboratory of Agricultural Equipment for Hilly and Mountainous Areas in Southeastern China(Co-construction by Ministry and Province),Ministry of Agriculture and Rural Affairs(Grant No.QSKF202304)Key Laboratory of Intelligent Equipment and Robotics for Agriculture of Zhejiang Province(Grant No.2022ZJZD2201).
文摘To solve the problems of excessive soil lumps,broken branches and seedlings in pods and difficulty in removing impurities in the harvested pods of peanuts in the hilly areas of southern China,which is due to the high soil viscosity and easy hardening,and to improve the soil removal effect of the peanut half-feed pod picker in hilly areas of China,this article designed a half-feed peanut-cleaning picker suitable for southern clay hilly areas and provided a detailed introduction to the overall structure,working principle,and adjustment methods of various operating parameters.Through field measurement experiments,the influencing factors and laws of soil removal performance indicators,such as the comprehensive soil removal rate and POD drop rate,were studied.The results showed that the comprehensive soil removal rate gradually increased with increasing soil patting frequency,soil patting amplitude,and picking roller speed,first increased and then decreased with increasing picking roller gap and gradually decreased with increasing soil patting plate gap and clamping conveyor chain speed.The comprehensive soil removal rate of the soil patting plate using the opposite patting method was greater than that of the swinging patting method.The soil removal pod drop rate increased gradually with increasing soil patting frequency and amplitude and decreased with increasing soil patting plate gap and clamping conveyor chain speed.The soil removal pod drop rate of the soil patting plate using swing patting was lower than that using the opposite patting method.The speed and gap of the picking roller had no effect on the soil removal pod drop rate.The frequency,amplitude,form,and gap of the soil patting plate had extremely significant impacts on the rate of decrease in the number of soil removal pod drop rate.The clamping conveyor chain speed had a significant impact,while the speed and gap of the picking roller had no significant impact.The influence of all factors on the comprehensive soil removal rate was extremely significant.
