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Spectral response of spider mite infested cotton:Mite density and miticide rate study

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International Journal of Agricultural and Biological Engineering 2013年第1期6卷 48-52页

作者： Yubin Lan Huihui Zhang w c hoffmann Jr.Juan D Lopez United States Department of Agriculture Agricultural Research ServiceAreawide Pest Management Research UnitCollege StationTexasUSA United States Department of Agriculture Agricultural Research ServiceWater Management Research UnitParlierCaliforniaUSA

Two-spotted spider mites are important pests in many agricultural *** mites(Acari:Tetranychidae)have been found to cause economic damage in corn,cotton,and *** glass vial bioassays indicate that Temprano™(abamectin)is the most toxic technical miticide for adult two-spotted spider *** an aerial application standpoint,additional research is needed to identify aerial application parameters for this *** objective of this study was to investigate spectral response of spider mite-infested cotton plants with different density levels of mites and treated with different rates of *** showed significantly different spectral signatures of cotton plants infested with different density levels of *** treating mite-infested cotton plants with five different Temprano rate treatments(control,one-eighth,one-fourth,one-half,and full rates),spectral reflectance curves were found to be significantly *** wavelengths of 550 nm,560 nm,680 nm and 740 nm were important for detecting the spectral differences among mite infested cotton plants treated with various rate of *** Difference Vegetative Index imagery was able to detect different levels of cotton plant ***-rate application of Temprano controlled mite-infested plants as effectively as the full-rate *** findings may lead to reduced cost and quantity of miticides used to maintain effective crop production and protection.

关键词： spectral reflectance infested cotton plants crop protection Normalized Difference Vegetative Index(NDVI) Temprano rate treatments

Multisensor Data Fusion for High Quality Data Analysis and Processing in Measurement and Instrumentation

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Journal of Bionic Engineering 2007年第1期4卷 53-62页

作者： Yan-bo Huang Yu-bin Lan w. c. hoffmann R. E. Lacey USDA ARS Agricultural Engineer Areawide Pest Management Research Unit Texas 77845 USA Biological and A g ricultural Engineering Department Texas A ＆M University Texas 77843-2117 USA

Multisensor data fusion （MDF） is an emerging technology to fuse data from multiple sensors in order to make a more accurate estimation of the environment through measurement and detection. Applications of MDF cross a wide spectrum in military and civilian areas. with the rapid evolution of computers and the proliferation of micro-mechanical/electrical systems sensors, the utilization of MDF is being popularized in research and applications. This paper focuses on application of MDF for high quality data analysis and processing in measurement and instrumentation. A practical, general data fusion scheme was established on the basis of feature extraction and merge of data from multiple sensors. This scheme integrates artificial neural networks for high performance pattern recognition. A number of successful applications in areas of NDI （Non-Destructive Inspection） corrosion detection, food quality and safety characterization, and precision agriculture are described and discussed in order to motivate new applications in these or other areas. This paper gives an overall picture of using the MDF method to increase the accuracy of data analysis and processing in measurement and instrumentation in different areas of applications.

关键词： multisensor data fusion artificial neural networks NDI food quality and safety characterization precision agriculture

Analysis of vegetation indices derived from aerial multispectral and ground hyperspectral data

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International Journal of Agricultural and Biological Engineering 2009年第3期2卷 33-40页

作者： Huihui Zhang Yubin Lan Ronald Lacey w.c.hoffmann Yanbo Huang Department of Biological and Agricultural Engineering Texas A&M UniversityCollege StationTexasUSA USDA-ARS College StationTexasUSA USDA-ARS APTRU141 Experiment Station RoadStonevilleMississippiUSA

Aerial multispectral images are a good source of crop,soil,and ground coverage *** reflectance indices provide a useful tool for monitoring crop growing status.A series of aerial images were obtained by an airborne MS4100 multispectral imaging system on the cotton and soybean *** hyperspectral data were acquired with a ground-based integration system at the same *** Normalized Difference Vegetative Index(NDVI),Simple Ratio(SR),and Soil Adjusted Vegetation Index(SAVI)calculated from both systems were analyzed and *** information derived from aerial multispectral images has shown the potential to monitor the general growth status of crop *** vegetation indices derived from both systems were significantly different(p-value was 0.073 atα=0.1 level)at the early growing stage of *** correlation coefficients of the image NDVI and ground NDVI were 0.3029 for soybean field and 0.338 for cotton *** and SR were not correlated.

关键词： airborne multispectral image hyperspectral reflectance vegetation index remote sensing crop growth condition

Scalable Ir‑Doped NiFe_(2)O_(4)/TiO_(2)Heterojunction Anode for Decentralized Saline wastewater Treatment and H_(2)Production

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Nano-Micro Letters 2025年第3期17卷 1-18页

作者： Sukhwa Hong Jiseon Kim Jaebeom Park Sunmi Im Michael R.hoffmann Kangwoo cho Division of Environmental Science and Engineering Pohang University of Science and Technology(POSTECH)Pohang 790−784Korea Linde Laboratory California Institute of TechnologyPasadenaCA 91125USA Institute for convergence Research and Education in Advanced Technology(I‑cREATE) Yonsei University International CampusIncheon 21983Republic of Korea

wastewater electrolysis cells(wEcs)for decentralized wastewater treatment/reuse coupled with H_(2)production can reduce the carbon footprint associated with transportation of water,waste,and energy *** study reports Ir-doped NiFe_(2)O_(4)(NFI,~5 at%Ir)spinel layer with TiO_(2)overlayer(NFI/TiO_(2)),as a scalable heterojunction anode for direct electrolysis of wastewater with circumneutral pH in a single-compartment *** dilute(0.1 M)Nacl solutions,the NFI/TiO_(2)marks superior activity and selectivity for chlorine evolution reaction,outperforming the benchmark IrO_(2).Robust operation in near-neutral pH was *** including operando X-ray absorption spectroscopy unveiled crucial roles of TiO_(2) which serves both as the primary site for cl−chemisorption and a protective layer for NFI as an ohmic *** electrolysis of NH4+-laden synthetic wastewater demonstrated that NFI/TiO_(2)not only achieves quasi-stoichiometric NH_(4)^(+)-to-N_(2)conversion,but also enhances H_(2)generation efficiency with minimal competing reactions such as reduction of dissolved oxygen and reactive *** scaled-up wEc with NFI/TiO_(2)was demonstrated for electrolysis of toilet wastewater.

关键词： wastewater electrolysis cell Ir-doped NiFe_(2)O_(4) Reactive chlorine species Decentralized H_(2)production On-site wastewater treatment

Development of a PwM Precision Spraying controller for Unmanned Aerial Vehicles

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Journal of Bionic Engineering 2010年第3期7卷 276-283页

作者： w.clint hoffmann Brad Fritz USDA-ARS College Station

This paper presents a new Pulse width Modulation (PwM) controller for Unmanned Aerial Vehicle (UAV) precisionsprayer for agriculture using a TL494 fixed-frequency pulse width modulator together with a data acquisition board and developedsoftware. An UAV can be remotely controlled or flown autonomously by pre-programmed flight plans. The PwMcontroller was implemented through the guidance system on the UAV with control commands sent between the UAV helicopterand the ground control station via a wireless telemetry system. The PwM controller was tested and validated using LabVIEw8.2. Several analyses were performed in a laboratory to test different control signals. The results show that the PwM controllerhas promise as a higher precision technique for spray applications, which will improve efficiency of pesticide application,especially in crop production areas.

关键词： PwM controller TL494 precision spraying UAV

Identification of greigite in lake sediments and its magnetic significance

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Science china Earth Sciences 2002年第1期45卷 81-87页

作者：胡守云 E.Appel V.hoffmann w.Schmahl 1. Nanjing Institute of Geography & Limnology Chinese Academy of Sciences 210008 Nanjing China 2. Institut für Geologie und Pal?ontologie Universit?t Tübingen 72076 Tübingen Germany 3. Institut für Mineralogie Ruhr-Universtit?t Bochum 44780 Bochum Germany

Detailed rock magnetic investigations and mineralogical analysis were conducted on lacustrine sediments recovered from Zoigê Basin, eastern Tibetan Plateau. Greigite, with fine and homogenous grain size, is found as a main magnetic carrier, which is suspected to be of biochemical origin. In contrast to some reports, greigite within the sediments is not oxidized even after exposure to air for a few years, which could be due to the fact that greigite is sealed by silicate.

关键词： greigite lacustrine sediments rock magnetism X-ray diffraction SEM

Mortality of Australian alpine grasses (Poa spp.) after drought: species differences and ecological patterns

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Journal of Plant Ecology 2012年第2期5卷 121-133页

作者： Philippa c.Griffin Ary A.hoffmann centre for Environmental Stress and Adaptation Research Department of GeneticsBio21 Institute30 Flemington RoadUniversity of MelbourneParkville 3010VictoriaAustralia

Aims Australian alpine ecosystems currently experience high precipitation in the snow-free season,but they are predicted to experience drier conditions under climate *** observed high mortality of the dominant alpine grasses following drought in *** aims were as follows:to test the involvement of plant-available water(PAw)and other environmental variables in grass mortality in the field;to detect possible species differences in drought response and to link soil moisture to precipitation using soil properties and climate *** The dominant tussock grasses of the Australian alpine zone,Poa hothamensis *** ***,Poa hiemata Vickery and Poa phillipsiana Vickery(Poaceae),all exhibited mortality following drought in the Bogong High Plains,Victoria,Australia in *** was calculated using soil water potential measurements,and past drought occurrence was modelled using climate *** then tested the effects of PAw and soil depth on grass survival both at a large spatial scale spanning the elevational range of the alpine zone and at a smaller *** hothamensis and *** were compared in a common-garden experiment to test drought *** Findings Poa hothamensis survival was predicted by dry-season PAw at the small spatial scale;at the large scale,soil depth and elevation were more important predictors of *** survival,but dry-season PAw predicted *** ***-garden experiments supported field observations that *** is more droughtsensitive than is *** also present a simple polynomial relationship between rainfall and field soil moisture,which predicts that the alpine soils dry below wilting point several times a *** suggest the timing of long rain-free periods may be more important than their duration.

关键词： climate change disturbance drought adaptation grassland

Gas Quenching during Age Hardening of the Aluminium casting Alloy Al-7Si-0.3Mg

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材料热处理学报 2004年第5期25卷 498-501页

作者： A. Rose O. Kessler F. hoffmann H.w. Zoch Stiftung Institutfttr werkstofftechnik Bremen GermanyStiftung Institutfttr Werkstofftechnik Bremen GermanyStiftung Institutfttr Werkstofftechnik Bremen GermanyStiftung Institutfttr Werkstofftechnik Bremen Germany

For quenching of age hardenable aluminium alloys today predominantly aqueous quenching media are used, which can lead due to the Leidenfrost phenomenon to a non-uniform cooling of the parts and thus to thermal stresses. Particularly at thin-walled or complex shaped parts local plastic deformations can occur by the uneven thermal stresses. In relation to the conventional quenching procedures in aqueous media, gas quenching exhibits a number of technological, ecological and economical advantages. In comparison to liquid quenching media, gas does not change its phase during quenching. Moreover, the cleaning problem of the parts can be avoided. The quenching intensity can be adjusted by the variable parameters gas pressure and gas speed as well as the kind of gas and thus can be adapted to the requirements of the alloy. By the higher uniformity and the better reproducibility, gas quenching offers a high potential to reduce distortion. The goal of these investigations is to clarify, if the cooling rate during gas quenching is sufficient to obtain the specific required strength after age hardening of the alloy Al-7Si-0.3Mg. For this purpose different tests in high-pressure gas quenching facilities, gas nozzle fields and water quenching baths were performed.

关键词：气体流淬火铝合金 Al-7Si-0.3Mg 沉淀硬化机械性质

红蜘蛛叶螨感染的棉花植株的光谱响应:螨密度和杀螨剂浓度的研究

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农业工程技术 2016年第15期36卷 80-页

作者： Yubin Lan Huihui Zhang w c hoffmann Jr.Juan D Lopez 王元杰王应宽美国农业部农业研究局野外害虫管理研究中心美国农业部农业研究局水资源管理研究中心

棉红蜘蛛(亚纲:叶螨科)是许多农业系统的重要害虫,现已经发现在玉米、棉花、高粱中造成过经济损失。成年红蜘蛛叶螨的生物测定指出,Temprano·(阿维菌素)对于成年叶螨来说是毒性最强的杀螨药。从航空应用的角度来看,还需要更多的研究来... 详细信息

棉红蜘蛛(亚纲:叶螨科)是许多农业系统的重要害虫,现已经发现在玉米、棉花、高粱中造成过经济损失。成年红蜘蛛叶螨的生物测定指出,Temprano·(阿维菌素)对于成年叶螨来说是毒性最强的杀螨药。从航空应用的角度来看,还需要更多的研究来确定杀螨药的航空应用参数。本研究的目的是探索感染不同叶螨密度及用不同浓度杀螨药处理的棉花植株的光谱响应。结果显示,棉花植物感染的螨虫密度不同,光谱特征明显不同。通过分析五种不同Temprano处理(对照,1/8,1/4,1/2,1)的棉花植株后发现,光谱反射率曲线明显不同。550 nm、560 nm、680 nm和740 nm四种波长对检测不同Temprano处理的叶螨感染的棉花植株光谱差异非常重要。归一化植被指数图像(NDVI)能够检测出棉花植物损伤的级别。1/2 Temprano处理的样本和1 Temprano处理的样本效果一样。本研究的发现可能会有助于降低用于作物生产和保护的杀螨药的成本和数量。

关键词：光谱反射受感染棉花植株作物保护归一化植被指数(NDVI) Temprano处理