Specific to problems of the existing round bale wrapping machine in China,such as small application scope and failing to satisfy the wrapping demands of round bales of different specifications,a tumbler-type round bal...Specific to problems of the existing round bale wrapping machine in China,such as small application scope and failing to satisfy the wrapping demands of round bales of different specifications,a tumbler-type round bale wrapping machine based on wrapping silage with stretch film was designed.By theoretical analysis and preliminary experiments of the corresponding wrapping process,revolving speed of tumbler,speed ratio between tumbler and carrier rollers,and pre-load force of stretch film were determined as experimental factors,while wrapping time and consumption of stretch film per unit mass of round bale were determined as evaluation indexes.Furthermore,quadratic regression orthogonal rotational combination experimental design was adopted to carry out the wrapping experiment.The regression models were set up,and influencing rules of experimental factors on evaluation indexes were also analyzed.The optimal parameter combination scheme was revolving speed of tumbler of 31-32 r/min,speed ratio between tumbler and carrier rollers of 2.6,and pre-load force of stretch film of 20-22 N.Under such a circumstance,the corresponding wrapping time required was 37.7-38.9 s and consumption of stretch film per unit mass of round bale was 3.21-3.46 kg/t.The predicted values and the measured values of evaluation indexes basically coincided with each other and the relative error fell below 5%,which indicated that both the optimized regression models acquired through the wrapping experiment and the relevant parameter optimization results were reliable.To guarantee the quality of rice straw silage,the round bale should be wrapped by no less than five layers of stretch films through the utilization of the tumbler-type round bale wrapping machine.The study results could be used as references for research and development of the round bale wrapping machine.展开更多
The loading ability of straw bale was tested by Electronical Testing Machine. The linear regression equations were proposed between failure density and loading ability, and failure density and compressing energy. Base...The loading ability of straw bale was tested by Electronical Testing Machine. The linear regression equations were proposed between failure density and loading ability, and failure density and compressing energy. Based on an exponent model, the testing coefficients of straw bale were estimated using Levenberg-Marquardt Method. The results of test showed that the relation between failure density and loading ability and compressing energy was linear in the phase of high density. The loading ability of straw bale could meet the building bill.展开更多
The study was conducted on Berbere Forest in Bale Zone of Oromia Regional State, south east of Ethiopia with the objective of determining the structural analysis and natural regeneration status of the forest. Systemat...The study was conducted on Berbere Forest in Bale Zone of Oromia Regional State, south east of Ethiopia with the objective of determining the structural analysis and natural regeneration status of the forest. Systematic sampling method was used to collect vegetation data. Seventy two nest quadrat sizes of 400 m2 (20 m × 20 m) for trees and shrubs were used. Within the main quadrat, two opposite side of each sub-quadrat of 25 m2 (5 m × 5 m) for sapling, 4 m2 (2 m × 2 m) for seedling of woody plants. The diameter and height were measured for all individual trees and shrubs having DBH (Diameter at Breast Height) ≥ 10 cm thick and ≥2 m height by using a diameter tape or caliper and clinometer respectively. For description and analysis of vegetation structure Diameter at Breast Height (DBH), basal area, tree density, height, frequency and important value index were used. Structural analysis of some selected tree species was revealed four different population patterns (bell shaped, inverted J-shaped, irregular and U-shaped). The total basal area of Berbere forest was 87.49 m2/ha, but most of the basal area was contributed by few large sized Moraceae family (Ficus vasta, Ficus ovate and Ficus thonningii) plant species. Analysis of regeneration status of woody plants in the forest showed 37.09% trees/shrubs species exhibited “good”, 19.35% showed “fair”, 6.45% showed “poor” and 25.81% trees/shrubs species were “not regenerating” at all and 11.29% trees/shrubs species were available only in sapling or seedling stage. Studies on the structure and regeneration of the forest indicated that there are species that require urgent conservation measures. Therefore, based on the results of this study, we recommended detail regenerating studies of seed bank in relation to various environmental factors such as soil type and properties.展开更多
Digitalization has nowadays raised interest in variable applications of farming.Increase of knowledge level,by means of unique identification,automation and control,farmers gain relevant business profit.This research ...Digitalization has nowadays raised interest in variable applications of farming.Increase of knowledge level,by means of unique identification,automation and control,farmers gain relevant business profit.This research is focused on the utilization of passive radio frequency identification(RFID)technology in silage bale application,both manual and automated level.Challenges arise due to silage conservation,varying environmental and seasonal conditions,different identification environments and RFID operation principle.Further maximum communication signal strength is limited by telecommunication standard regulations(e.g.,ETSI).The applicability of RFID technology with different commercial passive transponders is measured manually in a silage bale of 160 cm in diameter,covering 360 degrees around the bale.In addition,automated field tests are conducted in a real environment,where the data collection system is appended to a tractor and RFID reader antenna in a baler.Manual measurements are conducted as identification distance(meters)and transponder population(number of tags),while automated measurements are based on the number of successfully identified silage bales.Based on the manual measurement results,the most suitable tags for the automated field measurements were chosen,and the applicability to silage bale identification was verified.Field tests showed 100%success,with 151/151 uniquely identified silage bales.Achieved results prove that passive RFID operates well enough in silage bale identification,further enabling the development of digitalization of silage bale life cycle.展开更多
Loading ability of straw bales was tested by using an Electronical Testing Machine. Linear regression models were proposed to describe the loading ability as a function of failure density and compressing energy. Based...Loading ability of straw bales was tested by using an Electronical Testing Machine. Linear regression models were proposed to describe the loading ability as a function of failure density and compressing energy. Based on an exponent model, the testing compression coefficients of straw bales were estimated by using the Levenberg-Marquardt Method. Results showed that the relation among failure density, loading ability and compressing energy was linear in the phase of high density, Loading ability of straw bales could meet the requirement for building bills .展开更多
基金The authors acknowledge that this work was financially supported by the National Natural Science Foundation of China(Grant No.51405076)the 13th Five Years Key Programs for Science and Technology Development of China(Grant No.2016YFD0701300).
文摘Specific to problems of the existing round bale wrapping machine in China,such as small application scope and failing to satisfy the wrapping demands of round bales of different specifications,a tumbler-type round bale wrapping machine based on wrapping silage with stretch film was designed.By theoretical analysis and preliminary experiments of the corresponding wrapping process,revolving speed of tumbler,speed ratio between tumbler and carrier rollers,and pre-load force of stretch film were determined as experimental factors,while wrapping time and consumption of stretch film per unit mass of round bale were determined as evaluation indexes.Furthermore,quadratic regression orthogonal rotational combination experimental design was adopted to carry out the wrapping experiment.The regression models were set up,and influencing rules of experimental factors on evaluation indexes were also analyzed.The optimal parameter combination scheme was revolving speed of tumbler of 31-32 r/min,speed ratio between tumbler and carrier rollers of 2.6,and pre-load force of stretch film of 20-22 N.Under such a circumstance,the corresponding wrapping time required was 37.7-38.9 s and consumption of stretch film per unit mass of round bale was 3.21-3.46 kg/t.The predicted values and the measured values of evaluation indexes basically coincided with each other and the relative error fell below 5%,which indicated that both the optimized regression models acquired through the wrapping experiment and the relevant parameter optimization results were reliable.To guarantee the quality of rice straw silage,the round bale should be wrapped by no less than five layers of stretch films through the utilization of the tumbler-type round bale wrapping machine.The study results could be used as references for research and development of the round bale wrapping machine.
基金Supported by the Returnee Foundation of Ministry of Education and Project (1054hz023)Supported by the Key Research Foundation of Ministry of Science in Heilongjiang Province
文摘The loading ability of straw bale was tested by Electronical Testing Machine. The linear regression equations were proposed between failure density and loading ability, and failure density and compressing energy. Based on an exponent model, the testing coefficients of straw bale were estimated using Levenberg-Marquardt Method. The results of test showed that the relation between failure density and loading ability and compressing energy was linear in the phase of high density. The loading ability of straw bale could meet the building bill.
文摘The study was conducted on Berbere Forest in Bale Zone of Oromia Regional State, south east of Ethiopia with the objective of determining the structural analysis and natural regeneration status of the forest. Systematic sampling method was used to collect vegetation data. Seventy two nest quadrat sizes of 400 m2 (20 m × 20 m) for trees and shrubs were used. Within the main quadrat, two opposite side of each sub-quadrat of 25 m2 (5 m × 5 m) for sapling, 4 m2 (2 m × 2 m) for seedling of woody plants. The diameter and height were measured for all individual trees and shrubs having DBH (Diameter at Breast Height) ≥ 10 cm thick and ≥2 m height by using a diameter tape or caliper and clinometer respectively. For description and analysis of vegetation structure Diameter at Breast Height (DBH), basal area, tree density, height, frequency and important value index were used. Structural analysis of some selected tree species was revealed four different population patterns (bell shaped, inverted J-shaped, irregular and U-shaped). The total basal area of Berbere forest was 87.49 m2/ha, but most of the basal area was contributed by few large sized Moraceae family (Ficus vasta, Ficus ovate and Ficus thonningii) plant species. Analysis of regeneration status of woody plants in the forest showed 37.09% trees/shrubs species exhibited “good”, 19.35% showed “fair”, 6.45% showed “poor” and 25.81% trees/shrubs species were “not regenerating” at all and 11.29% trees/shrubs species were available only in sapling or seedling stage. Studies on the structure and regeneration of the forest indicated that there are species that require urgent conservation measures. Therefore, based on the results of this study, we recommended detail regenerating studies of seed bank in relation to various environmental factors such as soil type and properties.
文摘Digitalization has nowadays raised interest in variable applications of farming.Increase of knowledge level,by means of unique identification,automation and control,farmers gain relevant business profit.This research is focused on the utilization of passive radio frequency identification(RFID)technology in silage bale application,both manual and automated level.Challenges arise due to silage conservation,varying environmental and seasonal conditions,different identification environments and RFID operation principle.Further maximum communication signal strength is limited by telecommunication standard regulations(e.g.,ETSI).The applicability of RFID technology with different commercial passive transponders is measured manually in a silage bale of 160 cm in diameter,covering 360 degrees around the bale.In addition,automated field tests are conducted in a real environment,where the data collection system is appended to a tractor and RFID reader antenna in a baler.Manual measurements are conducted as identification distance(meters)and transponder population(number of tags),while automated measurements are based on the number of successfully identified silage bales.Based on the manual measurement results,the most suitable tags for the automated field measurements were chosen,and the applicability to silage bale identification was verified.Field tests showed 100%success,with 151/151 uniquely identified silage bales.Achieved results prove that passive RFID operates well enough in silage bale identification,further enabling the development of digitalization of silage bale life cycle.
基金Supported by National Natural Science Fund(50675071)Specialized Research Fund for Doctoral Program of Higher Education(20060564009)
文摘Loading ability of straw bales was tested by using an Electronical Testing Machine. Linear regression models were proposed to describe the loading ability as a function of failure density and compressing energy. Based on an exponent model, the testing compression coefficients of straw bales were estimated by using the Levenberg-Marquardt Method. Results showed that the relation among failure density, loading ability and compressing energy was linear in the phase of high density, Loading ability of straw bales could meet the requirement for building bills .
