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Reconstructing the size of individual trees using log data from cut-to-length harvesters in Pinus radiata plantations: a case study in NSW, Australia

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Journal of Forestry Research 2018年第1期29卷 13-33页

作者： Kuan Lu Huiquan Bi Duncan Watt Martin Strandgard Yun Li School of Information Science and Technology Beijing Forestry University Forest Science NSW Department of Industry–Lands and Forestry School of Ecosystem and Forest Sciences The University of Melbourne Snowy Region Forestry Corporation of NSW Australian Forest Operations Research Alliance (AFORA) University of the Sunshine Coast

With their widespread utilization, cut-to-length harvesters have become a major source of ‘‘big data’’ for forest management as they constantly capture, and provide a daily flow of, information on log production and assortment over large operational areas. Harvester data afford the calculation of the total log length between the stump and the last cut but not the total height of trees. They also contain the length and end diameters of individual logs but not always the diameter at breast height overbark（DBHOB） of harvested stems largely because of time lapse, operating and processing issues and other system deficiencies. Even when DBHOB is extracted from harvester data, errors and/or bias of the machine measurements due to the variation in the stump height of harvested stems from that specified for the harvester head prior to harvesting and diameter measurement errors may need to be corrected. This study developed（1） a system of equations for estimating DBHOB of trees from diameter overbark（DOB） measured by a harvester head at any height up to 3 m above ground level and（2） an equation to predict the total height of harvested stems in P. radiata plantations from harvester data. To generate the data required for this purpose, cut-to-length simulations of more than 3000 trees with detailed taper measurements were carried out in the computer using the cutting patterns extracted from the harvester data and stump height survey data from clearfall operations. The equation predicted total tree height from DBHOB, total log length and the small end diameter of the top log. Prediction accuracy for total tree height was evaluated both globally over the entire data space and locally within partitioned subspaces through benchmarking statistics. These statistics were better than that of the conventional height-diameter equations for P. radiata found in the literature, even when they incorporated stand age and the average height and diameter of dominant trees in the stand as predictors. So this equation when used with harvester

关键词： Cut-to-length simulations harvesters Big data Diameter and height estimation

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Recent Techniques for Harvesting Energy from the Human Body

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Computer Systems Science & Engineering 2022年第1期40卷 167-177页

作者： Nidal M.Turab Hamza Abu Owida Jamal I.Al-Nabulsi Mwaffaq Abu-Alhaija Department of Networks and Information Security Faculty of Information TechnologyAl-Ahliyya Amman UniversityAmman19328Jordan Medical Engineering Department Faculty of EngineeringAl-Ahliyya Amman UniversityAmman19328Jordan

The human body contains a near-infinite supply of energy in chemical,thermal,and mechanical forms.However,the majority of implantable and wear-able devices are still operated by batteries,whose insufficient capacity and large size limit their lifespan and increase the risk of hazardous material leakage.Such energy can be used to exceed the battery power limits of implantable and wear-able devices.Moreover,novel materials and fabrication methods can be used to create various medical therapies and life-enhancing technologies.This review paper focuses on energy-harvesting technologies used in medical and health applications,primarily power collectors from the human body.Current approaches to energy harvesting from the bodies of living subjects for self-powered electronics are summarized.Using the human body as an energy source encompasses numer-ous topics:thermoelectric generators,power harvesting by kinetic energy,cardi-ovascular energy harvesting,and blood pressure.The review considers various perspectives on future research,which can provide a new forum for advancing new technologies for the diagnosis,treatment,and prevention of diseases by integrating different energy harvesters with advanced electronics.

关键词： harvesters implantable medical devices thermoelectric generators cardiovascular systems human motion harvesters

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Influences of harvester and weather conditions on field loss and milling quality of rough rice

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International Journal of Agricultural and Biological Engineering 2017年第4期10卷 216-223页

作者： Ragab Khir Griffiths Atungulu Ding Chao Zhongli Pan Department of Biological and Agricultural Engineering University of CaliforniaDavisCA 95616USA Department of Agricultural Engineering Faculty of AgricultureSuez Canal UniversityIsmailiaEgypt Department of Food Science University of ArkansasFayettevilleAR 72701USA College of Food Science and Engineering Nanjing University of Finance and EconomiesNanjingJiangsu 210023China Healthy Processed Foods Research Unit Western Regional Research CenterAgricultural Research ServiceU.S.Department of AgricultureAlbanyCA 94710USA

A better understanding of factors affecting field losses and milling quality during harvest is needed to improve the economic value of rice.The main objective of this study was to evaluate the impact of harvester header,harvester type,and weather conditions on field loss and milling quality of rough rice.Four popular harvesters equipped with different headers:John Deere 9870 with header D60-S,John Deere 9860 with header D972-S,Hardy,and John Deere 9770 with stripper header were evaluated in this study.The header and total field losses of rice were evaluated for each harvester under regular,rainy and windy weather conditions.Tests were conducted in a rice field cultivated with medium grain rice,variety M206,at Grimes,CA.Total rice yield(TRY),head rice yield(HRY)and whiteness index(WI)were examined to evaluate the effect of weather conditions on milling quality.The obtained results revealed that the rice field loss was affected by harvester header and type,and weather conditions.Among the conventional headers,D60-S significantly reduced the rice loss compared to the D972-S and the Hardy.Harvesting with John Deere 9860 resulted in significant header and field loss compared to other tested harvesters.The average loss increased from 236.2 kg/hm^(2)and 445.2 kg/hm^(2)under regular condition to 711.1 kg/hm^(2)and 907.9 kg/hm^(2)under windy condition for John Deere 9870 and John Deere 9860,respectively.The corresponding loss percentages increased from 2.6%and 4.9%to 7.9%and 10.1%.HRY was significantly affected by weather condition at harvest time.However,the weather condition had no significant effect on TRY and WI.To minimize the rice field loss and obtain good milling quality,commercial rice harvesting during regular weather conditions is important.A proper combination of harvester type and header could be vital for reducing the rice loss.

关键词： rice harvesters field loss weather conditions milling quality harvester header

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Kinematics analysis for five DOF Fresh Fruit Bunch harvester

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International Journal of Agricultural and Biological Engineering 2010年第3期3卷 1-7页

作者： Helena Anusia James Jayaselan Wan Ishak Wan Ismail Department of Biology and Agriculture Faculty of EngineeringUniversiti Putra Malaysia43400 SerdangSelangor Darul EhsanMalaysia

The existing mechanized oil palm harvester is claimed to be unsuccessful due to its inefficiency to harvest Fresh Fruit Bunch(FFB).It takes a lot of time compared to the conventional harvesting method,using human power.Therefore a study was carried out using Denavit and Hartenberg(D-H)approach to automate the five Degrees of Freedom(DOF)harvester manipulator.The general objective was to reduce the number of workers required for harvesting as well as to provide comfortable ergonomic for the operator of oil palm harvester.The D-H’s convention was used for selecting frames of reference in robotics application which has become the standard way of representing robots and modeling their motions.In this study,the forward kinematics and inverse kinematics were used to deduce joint angles variables while the conventional Jacobian was used for motion velocity computation.The formulated inverse equations were tested manually on the harvester with given locations to obtain deduced joint angles.The results were θ_(1)=129.64°,θ_(3)=180°,θ_(4)=90°,which were quite accurate.Thus,the kinematics analysis of harvester arm automation was done successfully.

关键词： kinematics Degrees of Freedom harvesters manipulators denavit and hartenberg Fresh Fruit Bunch

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