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- Author:
- Zhu, Heping, et al. ; Jeon, Hong Y.; Tian, Lei F.; Show all 3 Authors
- Source:
- Sensors 2011 v.11 no.6 pp. 6270-6283
- ISSN:
- 1424-8220
- Subject:
- lighting; image analysis; algorithms; weeds; automatic detection; statistical analysis; neural networks; crops; field experimentation
- Abstract:
- ... An image processing algorithm for detecting individual weeds was developed and evaluated. Weed detection processes included were normalized excessive green conversion, statistical threshold value estimation, adaptive image segmentation, median filter, morphological feature calculation and Artificial Neural Network (ANN). The developed algorithm was validated for its ability to identify and detect ...
- Handle:
- 10113/50088
- DOI:
- 10.3390/s110606270
- PubMed:
- 22163954
- PubMed Central:
- PMC3231458
- https://doi.org/10.3390/s110606270
- Author:
- Zhu, Heping, et al. ; Salyani, Masoud; Fox, Robert D.; Show all 3 Authors
- Source:
- Paper 2010 no.1008502 pp. -
- ISSN:
- 0149-9890
- Subject:
- spraying; spray deposition; droplet size; spray coverage; droplet studies; electronic equipment; image analysis; computer software
- Abstract:
- ... Preventing over- or under–spray applications on intended targets require a feedback technology to improve the spray coverage efficiency. A portable scanning system was developed that could quickly evaluate spray deposit distribution on deposit collectors. The system is integrated with a handheld business card scanner, deposit collectors, a laptop computer, and a custom-designed software "DepositSc ...
- Handle:
- 10113/47313
- Author:
- Zhu, Heping, et al. ; Gu, Jiabing; Ding, Weimin; Jeon, Hong Young; Show all 4 Authors
- Source:
- Atomization and sprays 2011 v.21 no.3 pp. 263-274
- ISSN:
- 1936-2684
- Subject:
- adjuvants; air; air flow; canopy; droplet size; droplets; equipment design; nozzles; solenoids; sprayers; surface tension; surfactants; viscosity
- Abstract:
- ... Verification of droplet size distributions is essential for the development of real-time variable-rate sprayers that synchronize spray outputs with canopy structures. Droplet sizes from a custom-designed, air-assisted, five-port nozzle coupled with a pulse-width-modulated (PWM) solenoid valve were measured under various operating conditions. Parameters included five air velocities (0, 10, 30, 50, ...
- Handle:
- 10113/54120
- DOI:
- 10.1615/AtomizSpr.2011003258
- https://doi.org/10.1615/AtomizSpr.2011003258
- Author:
- Zhu, Heping, et al. ; Altland, James; Derksen, Richard C.; Krause, Charles R.; Show all 4 Authors
- Source:
- HortTechnology 2011 v.21 no.3 pp. 367-375
- ISSN:
- 1063-0198
- Subject:
- ornamental trees; bare root stock; nursery crops; sprayers; application rate; droplets; density; pesticide application; spray coverage; spray deposition; pest control; equations; height; pesticide use reduction
- Abstract:
- ... Spray deposition and coverage at different application rates for nursery liners of different sizes were investigated to determine the optimal spray application rates. Experiments were conducted on 2- and 3-year-old ‘Autumn Spire’ red maple (Acer rubrum) liners. A traditional hydraulic sprayer with vertical booms between tree rows was used to apply the spray applications. Application rates were 10, ...
- Handle:
- 10113/50122
- Author:
- Zhu, Heping, et al. ; Xu, Linyun; Ozkan, H. Erdal; Show all 3 Authors
- Source:
- Paper 2009 no.096671 pp. -
- ISSN:
- 0149-9890
- Subject:
- pesticide application; relative humidity; contact angle; evaporation rate; air temperature; pesticide adjuvants; plant veins; nonionic surfactants; droplets; leaves; droplet studies
- Abstract:
- ... Leaf surfaces are often altered when attacked by various insects and diseases. To evaluate the effect of droplet deposition on pesticide application efficiency, evaporation and deposit pattern formation of single droplets deposited at various locations on waxy leaves were investigated under controlled conditions. The locations on leaves included the intervenial area, midrib and secondary vein on b ...
- Handle:
- 10113/40818
- Author:
- Zhu, Heping, et al. ; Derksen, Richard; Paul, Pierce; Ozkan, H. Erdal; Show all 4 Authors
- Source:
- Paper 2010 no.1009142 pp. -
- ISSN:
- 0149-9890
- Subject:
- Triticum aestivum; stem rot; field experimentation; plant pathogenic fungi; fungicides; pesticide application; scab diseases; spray volume; droplet size; fluorescent labeling; air-assisted sprayers
- Abstract:
- ... New variants of wheat pathogens are emerging in various countries for which there is no known resistance. The current movement of these pathogens suggests that their incursion into the US is imminent. The objective of this work was to identify effective application parameters to apply fungicides for protecting against wheat head scab and stem rust infection. Field trials were designed to evaluate ...
- Handle:
- 10113/47457
- Author:
- Zhu, Heping, et al. ; Xu, Linyun; Ozkan, H. Erdal; Thistle, Harold W.; Show all 4 Authors
- Source:
- Biosystems engineering 2010 v.106 no.1 pp. 58-67
- ISSN:
- 1537-5110
- Subject:
- evaporation rate; water; droplets; wettability; surfactants; leaves; ionic strength; surface active properties; pesticide application; application technology
- Abstract:
- ... The evaporation and formation of deposit patterns from single droplets deposited at various locations on waxy leaves were investigated under controlled conditions. Leaf locations included the interveinal area, midrib and secondary vein on both adaxial and abaxial surfaces. Tests were conducted with 300 and 600 μm diameter droplets containing water and a non-ionic surfactant. The ambient temperatur ...
- Handle:
- 10113/42947
- DOI:
- 10.1016/j.biosystemseng.2010.02.004
- https://doi.org/10.1016/j.biosystemseng.2010.02.004
- Author:
- Zhu, Heping, et al. ; Xu, Linyun; Ozkan, Erdal H.; Bagley, William E.; Show all 4 Authors
- Source:
- Paper 2010 no.1008586 pp. -
- ISSN:
- 0149-9890
- Subject:
- Pelargonium; leaves; surface quality; pesticide application; pesticide adjuvants; evaporation; seed oils; nonionic surfactants; droplets; wettability
- Abstract:
- ... Adjuvants have been used to improve pesticide application efficiency and effectiveness for many years. However, knowledge on quantitative reactions of adjuvant-amended pesticide droplets on foliage is lacking. Evaporation rate and wetted area of 500 µm droplets with four different adjuvants on waxy and hairy leaves were measured inside an environment-controlled chamber. The adjuvants included Crop ...
- Handle:
- 10113/47518
- Author:
- Zhu, Heping, et al. ; Xu, Linyun; Ozkan, H. Erdal; Bagley, William E.; Krause, Charles R.; Show all 5 Authors
- Source:
- Pest management science 2011 v.67 no.7 pp. 842-851
- ISSN:
- 1526-498X
- Subject:
- chemical concentration; petroleum; surface tension; pesticide application; horticultural oils; trichomes; pesticide mixtures; seed oils; pesticide adjuvants; water; surfaces; evaporation; wettability; nonionic surfactants; droplets; epicuticular wax; leaves
- Abstract:
- ... Background: Adjuvants can improve pesticide application efficiency and effectiveness. However, quantifications of the adjuvant-amended pesticide droplet actions on foliage, which could affect application efficiencies, are largely unknown. Results: Droplet evaporation rates and spread on waxy or hairy leaves varied greatly with the adjuvant types tested. On waxy leaves, the wetted areas of droplets ...
- Handle:
- 10113/49641
- DOI:
- 10.1002/ps.2122
- https://doi.org/10.1002/ps.2122
- Author:
- Zhu, Heping, et al. ; Xu, Linyun; Ozkan, H. Erdal; Bagley, Bill; Show all 4 Authors
- Source:
- Paper 2009 no.096675 pp. -
- ISSN:
- 0149-9890
- Subject:
- pesticide application; relative humidity; contact angle; evaporation rate; air temperature; foliar application; pesticide adjuvants; nonionic surfactants; leaves; droplet studies
- Abstract:
- ... Appropriate adjuvant selection for pesticide applications is central to improve spray performances on waxy leaves and to reduce off-target losses. Evaporation and deposition patterns of 500 μm sessile droplets with five classes of adjuvants on five different waxy plants were investigated. Droplets generated with a single droplet generator were deposited on target leaves placed in a controlled envi ...
- Handle:
- 10113/40822
- Author:
- Zhu, Heping, et al. ; Reding, Michael E.; Derksen, Richard; Show all 3 Authors
- Source:
- Journal of environmental horticulture 2008 v.26 no.2 pp. 93-100
- ISSN:
- 0738-2898
- Subject:
- Scarabaeidae; larvae; insect control; chemigation; control methods; ornamental trees; nursery crops; imidacloprid; entomopathogenic nematodes; clothianidin; microirrigation; pesticide application; Cornus kousa
- Abstract:
- ... Larvae of scarabs, also known as white grubs, are subterranean insects that damage ornamental nursery crops when they feed on roots. Management is generally based on application of chemical insecticides to the soil surface, followed by supplemental water to leach the toxicants into the soil. Drip irrigation systems have the potential to deliver insecticides and insect pathogens to the root zones o ...
- Handle:
- 10113/47827
- Author:
- Zhu, Heping, et al. ; Zhou, Hongping; Ru, Yu; Shu, Chaoran; Zheng, Jiaqiang; Show all 5 Authors
- Source:
- Paper 2009 no.097378 pp. -
- ISSN:
- 0149-9890
- Subject:
- pesticide application; aerial application; spraying; agricultural aviation; helicopters; sprayers; droplet studies
- Abstract:
- ... It is wide foreground that aerial electrostatic spraying technology is applied for prevention and cure pests in agriculture and forestry. In the field of agriculture aviation, there are some advantages about helicopter such as flight convenience and realizing pesticide spraying in low-altitude flying. Be aimed at using R44 helicopter which is made in USA Robinson company, an aerial electrostatic s ...
- Handle:
- 10113/40806
- Author:
- Zhu, Heping, et al. ; Jeon, Hong Y.; Derksen, Richard C.; Ozkan, H. Erdal; Krause, Charles R.; Show all 5 Authors
- Source:
- Paper 2010 no.1008801 pp. -
- ISSN:
- 0149-9890
- Subject:
- wind; air temperature; precision agriculture; field experimentation; equipment performance; ultrasonic equipment; variable rate application; sprayers; spraying
- Abstract:
- ... Reliable function of sensors under rough field conditions is required for the development of variable-rate sprayers to deliver pest control agents to tree liners in ornamental nurseries. Two ultrasonic sensors were examined to identify how their durability and detection stability would be influenced by the changes in temperature, wind, dust, travel speed and spray cloud. One of the sensors did not ...
- Handle:
- 10113/47343
- Author:
- Zhu, Heping, et al. ; Derksen, Richard Charles; Ranger, Christopher M.; Canas, Luis A.; Krause, Charles R.; Show all 5 Authors
- Source:
- Applied engineering in agriculture 2010 v.26 no.6 pp. 947-953
- ISSN:
- 0883-8542
- Subject:
- greenhouse experimentation; Euphorbia pulcherrima; mature plants; air-assisted sprayers; application parameters; pesticide application; leaves; equipment performance
- Abstract:
- ... Understanding the performance characteristics of application equipment is important for helping make the most efficacious applications. While handguns making high volume applications are common in greenhouse production, it is difficult to achieve uniform distribution of product in a timely manner. Broadcast applications made using air-assistance can help aid canopy penetration and the volume of ca ...
- Handle:
- 10113/48588
- Author:
- Zhu, Heping, et al. ; Xu, Linyun; Ozkan, Erdal; Bagley, William E.; Derksen, Richard C.; Krause, Charles R.; Show all 6 Authors
- Source:
- Transactions of the ASABE 2010 v.53 no.1 pp. 13-20
- Subject:
- foliar spraying; ornamental plants; Begonia; Kalanchoe; contact angle; greenhouse production; seed oils; pesticide adjuvants; water; spray coverage; nonionic surfactants; evaporation; spray deposition; Pelargonium peltatum; waxes; leaves; droplet studies
- Abstract:
- ... The use of an appropriate adjuvant for pesticide applications is a critical process to improve spray deposit characteristics on waxy leaves and to reduce off-target losses. After deposition and evaporation, residue patterns of 500 ° m sessile droplets that incorporated four classes of adjuvants on five different waxy plants were investigated. Droplets were generated with a single-droplet generator ...
- Handle:
- 10113/41032
- Author:
- Zhu, Heping, et al. ; Krause, Charles R.; Derksen, Richard C.; Horst, Leona E.; Zondag, Randall; Show all 5 Authors
- Source:
- Scanning 2009 v.31 no.1 pp. 24-27
- ISSN:
- 0161-0457
- Subject:
- Venturia inaequalis; fungal diseases of plants; disease control; apples; cultivars; sprayers; spraying; spray deposition; spray coverage; scanning electron microscopy
- Abstract:
- ... Foliar diseases like apple scab result in significant economic losses to growers each year. Assessment in past studies involved only macroscopic disease ratings. More complete knowledge of the fate and behavior of fungicide has been needed to reduce pesticide use with less off-target contamination. Field studies were conducted in a production nursery for over 4 years. A moderately susceptible cult ...
- Handle:
- 10113/32344
- DOI:
- 10.1002/sca.20138
- PubMed:
- 19172634
- https://doi.org/10.1002/sca.20138
- Author:
- Zhu, Heping, et al. ; Psychoudakis, Dimitris; Moulder, William; Chen, Chi-Chih; Volakis, John L.; Show all 5 Authors
- Source:
- IEEE antennas and wireless propagation letters 2008 v.7 no. pp. 444-447
- ISSN:
- 1548-5757
- Subject:
- Agrilus planipennis; detectors; insect behavior; insect flight; insect pests; portable equipment; radar; radio frequency identification
- Abstract:
- ... Harmonic radar systems provide an effective modality for tracking insect behavior. This letter presents a harmonic radar system proposed to track the migration of the Emerald Ash Borer (EAB). The system offers a unique combination of portability, low power and small tag design. It is comprised of a compact radar unit and a passive RF tag for mounting on the insect. The radar unit transmits a 5.96 ...
- Handle:
- 10113/53786
- DOI:
- 10.1109/LAWP.2008.2004512
- https://doi.org/10.1109/LAWP.2008.2004512
18. Evaluation of Handgun and Broadcast Systems for Spray Deposition in Greenhouse Poinsettia Canopies
- Author:
- Zhu, Heping, et al. ; Derksen, Richard Charles; Ranger, Christopher M.; Canas, Luis A.; Locke, James C.; Krause, Charles R.; Show all 6 Authors
- Source:
- Transactions of the ASABE 2010 v.53 no.1 pp. 5-12
- Subject:
- foliar spraying; canopy; Euphorbia pulcherrima; greenhouse production; fan nozzles; spray coverage; air-assisted sprayers; spray deposition; leaves; droplet studies
- Abstract:
- ... Handgun applicators are popular, general-purpose greenhouse sprayers. However, there are few recommendations on how to use them to treat plant benches. Handgun applications made from one side can result in significant differences in deposits between the side of the plant facing the spray stream and the opposite side. Broadcast spraying over the top of the canopy may improve spray distribution acro ...
- Handle:
- 10113/41031
- Author:
- Zhu, Heping, et al. ; Yu, Yang; Ozkan, H. Erdal; Derksen, Richard C.; Krause, Charles R.; Show all 5 Authors
- Source:
- Paper 2008 no.083752 pp. -
- ISSN:
- 0149-9890
- Subject:
- spray drift; droplet size; surfactants; pesticide residues; evaporation; droplets; pesticide formulations; spraying; additives
- Abstract:
- ... Evaporation time and wetted area of single droplets sizing from 246 to 886 μm at relative humidity (RH) ranging from 30 to 90% were measured with sequential images under controlled laboratory conditions. Droplets were placed inside an environmental-controlled chamber under a stereoscope and a high definition digital camera. The spray mixtures used to form droplets included different combinations o ...
- Handle:
- 10113/31945
- Author:
- Zhu, Heping, et al. ; Fox, Robert D.; Derksen, Richard C.; Brazee, Ross D.; Svensson, Sven Axel; Show all 5 Authors
- Source:
- Transactions of the ASABE 2008 v.51 no.2 pp. 405-410
- Subject:
- orchards; spray drift; equipment design; equipment performance; air-assisted sprayers; spraying
- Abstract:
- ... The design and operating procedures of air-blast sprayers have been greatly improved over the past 50 years. Early tree and vine spray application equipment used hand-guns that required a large amount of water. Later, sprayers with efficient fans, producing large volumes of air at high velocities, were developed for large fruit and nut trees. Recently, apple growers have planted many dwarf and sem ...
- Handle:
- 10113/19589