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Closed-loop drip irrigation control using a hybrid wireless sensor and actuator network

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science China(Information sciences) 2011年第3期54卷 577-588页

作者： FRANZEN aaron Department of Biosystems and Agricultural Engineering Oklahoma State University

In this research, a closed-loop drip irrigation control hybrid wireless sensor and actuator network (HWsAN) prototype were developed and deployed in a crop field for soil property precise measurement and precision irrigation in accordance with the measured soil property. The HWsAN was composed of a wireless sensor and actuator network (WsAN) used for in-field soil property monitoring and irrigation control and a laboratory supervising system. The WsAN included ten sensor nodes, five irrigation control nodes, a central node, a gateway and a cellular modem. The laboratory supervising system was formed by a web-server. The system could automatically sample soil properties including soil moisture, electrical conductivity, and nearsurface temperature at four different depths underground and transmit field data through cellular network to the web-server. Closed-loop control was achieved through the control nodes listening uploading packets from its paired sensor nodes to control drip irrigation. Results from the quality of service (Qos) evaluation included: the data packet transmission rate was 84.76%, data accuracy rate was greater than 97% and no in-field data transmission errors.

关键词： wireless sensor network drip irrigation soil property monitoring precision agriculture

Microsurgical epididymal sperm aspiration： indications, techniques and outcomes

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Asian Journal of Andrology 2013年第1期15卷 40-43页

作者： aaron M Bernie Ranjith Ramasamy Doron s stember Peter J stahl Weill Cornell Medical College New York-Presbyterian Hospital New York NY 10021 USA Beth Israel Medical Center of Albert Einstein College of Medicine of YeshivaUniversity New York NY 10003 USA Columbia University College of Physicians & surgeons New York-Presbyterian Hospital New York NY 10032 USA

Microsurgical epididymal sperm aspiration （MEsA） refers to retrieval of sperm-containing fluid from optimal areas of the epididymis that are selected and sampled using high-power optical magnification provided by an operating microscope. Retrieved sperm are subsequently used for intracytoplasmic sperm injection （ICsI） to induce fertilization and pregnancy. MEsA is considered by many experts to be the gold standard technique for sperm retrieval in men with obstructive azoospermia given its high yield of quality sperm, excellent reported fertilization and pregnancy rates, and low risk of complications. However, MEsA must be performed in an operating room, requires microsurgical skills and is only useful for reproduction using ICsI. Herein we present an overview of the evaluation of candidate patients for MEsA, the technical performance of the procedure and the outcomes that have been reported.

关键词： azoospermia ICsI infertility male MEsA microsurgical epididymal sperm aspiration microsurgery sperm retrieval

The kinetics of static recovery by dislocation climb

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npj Computational Materials 2022年第1期8卷 973-982页

作者： aaron A.Kohnert Laurent Capolungo Materials science and Technology Division Los Alamos National LaboratoryLos AlamosNMUSA

The initial microstructure of a wide range of structural materials is conditioned by thermo-mechanical treatments such as hot-working,tempering,or solution *** the elevated temperatures associated with these treatments the dislocation microstructure evolves,usually decreasing in density through a process known as static *** its technological relevance,static recovery is not fully characterized from a theoretical standpoint,with even the controlling mechanisms subject to *** this study,a climb-enabled discrete dislocation dynamics(DDD)capability is leveraged to explore the kinetics of static recovery in pure Fe when controlled by dislocation *** data from these simulations is used to develop a revised static recovery law,and provides the parameters appropriate for predictive microstructure models in *** law differs from previous analytical derivations invoking climb of dislocations,following the logarithmic trends typical of experimental observations where prior work did *** comparison between the recovery law derived from DDD to experimental recovery data in alpha Fe shows strong agreement across a range of temperatures,and suggests that climb is the controlling mechanism for static recovery in pure metals.

关键词： dislocation law treatment

A causation mechanism for coal bursts during roadway development based on the major horizontal stress in coal:Very specific structural geology causing a localised loss of effective coal confinement and Newton’s second law

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International Journal of Mining science and Technology 2020年第1期30卷 39-47页

作者： Russell Frith Guy Reed aaron Jones Mine Advice Pty Ltd BeresfieldNew South Wales 2322Australia

In 2017,one of the international authorities on coal bursts,Mark Christopher,published a paper entitled"Coal bursts that occur during development:A rock mechanics enigma",in which several relevant technical issues were *** paper outlines what is considered to be a credible,first-principles,mechanistic explanation for these three current development coal burst conundrums by reference to early published coal testing work examining the significance of a lack of"constraint"to coal stability and an understanding of how very specific structural geology and other geological features can logically cause this to occur in situ,albeit on a statistically very rare *** basic model is examined by reference to published information pertaining to the development coal-burst that occurred at the Austar Coal Mine in New south Wales,Australia,in 2014 and from the sunnyside District in Utah,the United ***"cause and effect"model for development of coal bursts presented also offers a meaningful explanation for the statistical improbability for what are nonetheless potentially highly-destructive events,being able to explain the statistical rarity being just as important to the credibility of the model as explaining the local conditions associated with burst *** model could also form the basis for a robust,riskbased approach utilising a"hierarchy of controls",to the operational management of the development coal burst ***,the use of pre-mining predictions for likely burst-prone and non-burstprone areas,the use of the mine layout to avoid or at least minimise mining within burst-prone areas if appropriate,and finally the development of an operational Trigger Action Response Plan(TARP)that reduces the likelihood of inadvertent roadway development into a burst-prone area without suitable safety controls already being in place.

关键词： Development coal burst Wing-cracks Austar Mine sunnyside Mine Major horizontal stress in coal

An anisotropic propagation technique for synthesizing hyperbranched polyvillic gold nanoparticles

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Nano Research 2016年第10期9卷 2889-2903页

作者： aaron s. schwartz-Duval santosh K. Misra Prabuddha Mukhejee Elyse Johnson Alvin s. Acerbo Dipanjan Pan Department of Bioengineering and Beckman Institute University of Illinois Urbana-Champaign Urbana 61801 USA Biomedical Research Center Carle Foundation Hospital Urbana 61801 USA Cytoviva Inc. Auburn 36830 USA Center for Advanced Radiation sources The University of Chicago Chicago 60637 USA

Of late, many synthesis processes have been studied to develop irregular nano-rnorphologies of gold nanostructures for biomedical applications in order to increase the efficacy of nanoparticle theranostics, tune the plasmonic absorbance spectra, and increase the sensitivity of biomolecule detection through surface enhanced Raman spectroscopy. Here we report, a novel, non-seed mediated versatile single pot synthesis method capable of producing hyperbranched gold ＂nano-polyvilli＂ with more than 50-90 branching nanowires propagating from a single origin within each structure. The technique was capable of achieving precise tuning of the branch propagation where the branching could be controlled by varying the duration of incubation, temperature, and hydrogen ion concentration.

关键词： gold nanoparticles surface enhanced Raman spectroscopy (sERs) anisotropy asymmetric nanocrystallization

Global optimal path planning for mobile robot based onimproved Dijkstra algorithm and ant system algorithm

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Journal of Central south University of Technology 2006年第1期13卷 80-86页

作者：谭冠政贺欢 aaron sloman school of Information science and Engineering Central South University Changsha 410083 China School of Computer Science The University of Birmingham Birmingham B15 2TT UK school of Information science and Engineering Central South University Changsha 410083 China school of Computer science The University of Birmingham Birmingham B15 2TT UK

A novel method of global optimal path planning for mobile robot was proposed based on the improved Dijkstra algorithm and ant system algorithm. This method includes three steps: the first step is adopting the MAKLINK graph theory to establish the free space model of the mobile robot, the second step is adopting the improved Dijkstra algorithm to find out a sub-optimal collision-free path, and the third step is using the ant system algorithm to adjust and optimize the location of the sub-optimal path so as to generate the global optimal path for the mobile robot. The computer simulation experiment was carried out and the results show that this method is correct and effective. The comparison of the results confirms that the proposed method is better than the hybrid genetic algorithm in the global optimal path planning.

关键词： mobile robot global optimal path planning improved Dijkstra algorithm ant system algorithm MAKLINK graph free MAKLINK line

Trends in forensic DNA database:transnational exchange of DNA data

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Forensic sciences Research 2020年第1期5卷 8-14页

作者： aaron Opoku Amankwaa science and Justice Research Interest Group School of LawNorthumbria UniversityNewcastle Upon TyneUK

The transnational exchange of forensic DNA data has become a modern trend in fighting cross-border crime,terrorism and illegal *** DNA data allow the police to identify,eliminate or link individuals associated with a ***,different crime scenes can be linked via the DNA profile to identify serial offenders or determine crime *** to the transnational exchange of DNA data can be categorized into four:(1)creation of an international DNA database,(2)linked or networked national DNA data-bases,(3)request-based exchange of data,and(4)a combination of *** countries operate the combination system of data *** paper briefly introduces the different approaches in the transnational sharing of forensic DNA data,the legislative and operational framework,pattern of data exchange and participating states,and policy challenges associ-ated with data ***,most DNA exchange systems are modelled as the European Union Prüm *** operates under two stages:hit/no-hit query and further information *** scope of the data exchange is governed by individual national legislation that determines the type of information that can be shared and the national authority responsible for the *** DNA data exchange has been instrumental in resolving serious crimes such as gang and serial rape,and armed robbery,adequate infor-mation about their overall effectiveness and efficiency is ***,operational,legal and ethical challenges including issues of privacy and proportionality appear to limit the full potential of the DNA data exchange system.

关键词： Forensic DNA exchange Prüm forensic DNA legislation genetic privacy proportionality social security

GANana:Unsupervised Domain Adaptation for Volumetric Regression of Fruit

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Plant Phenomics 2021年第1期3卷 326-336页

作者： Zane K.J.Hartley aaron s.Jackson Michael Pound Andrew P.French school of Computer science University of NottinghamNG71BBUK school of Biosciences University of NottinghamLE125RDUK

3D reconstruction of fruit is important as a key component of fruit grading and an important part of many size estimation *** many computer vision challenges,the 3D reconstruction task suffers from a lack of readily available training data in most domains,with methods typically depending on large datasets of high-quality image-model *** this paper,we propose an unsupervised domain-adaptation approach to 3D reconstruction where labelled images only exist in our source synthetic domain,and training is supplemented with different unlabelled datasets from the target real *** approach the problem of 3D reconstruction using volumetric regression and produce a training set of 25,000 pairs of images and volumes using hand-crafted 3D models of bananas rendered in a 3D modelling environment(Blender).Each image is then enhanced by a GAN to more closely match the domain of photographs of real images by introducing a volumetric consistency loss,improving performance of 3D reconstruction on real *** solution harnesses the cost benefits of synthetic data while still maintaining good performance on real world *** focus this work on the task of 3D banana reconstruction from a single image,representing a common task in plant phenotyping,but this approach is general and may be adapted to any 3D reconstruction task including other plant species and organs.

关键词： image render adapted

Effects of contaminant metal ions on precipitation recovery of rare earth elements using oxalic acid

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Journal of Rare Earths 2022年第3期40卷 482-490,I0005页

作者： Wencai Zhang aaron Noble Bin Ji Qi Li Department of Mining and Minerals Engineering Virginia Polytechnic Institute and State UniversityBlacksburgVA24061USA

solution equilibrium calculations were performed in this study to understand the impact of contaminant metal ions on the precipitation efficiency of selected rare earth elements(Ce^(3+),Nd^(3+),and Y^(3+))using oxalic acid as a *** metal ions,Al^(3+) and Fe^(3+),are found to considerably affect the precipitation efficiency of *** Al^(3+) and Fe^(3+)concentrations are increased by 1×10^(−4) mol/L,in order to achieve an acceptable cerium recovery of 93%from solutions containing 1×10^(−4) mol/L Ce^(3+),oxalate dosage needs to increase by 1.2×10^(−4) and 1.68×10^(−4) mol/L,*** great impacts on the required oxalate dosage are also observed for Nd^(3+) and Y^(3+),which indicates that oxalic acid consumption and cost will be largely increased when the trivalent metal ions exist in REE-concentrated *** of the divalent metal ions on the oxalate dosage are ***,solution equilibrium calculation results show that the precipitation of Fe^(3+) and Ca^(2+)(e.g.,hematite and Ca(C_(2)O_(4))∙H_(2)O(s))likely occurs during the oxalate precipitation of REEs at relatively high pH(e.g.,pH 2.5),which will reduce rare earth oxalate product *** addition to the metal ions,anionic species,especially sO_(4)^(2-),are also found to negatively affect the precipitation recovery of *** example,when 0.1 mol/L sO_(4)^(2-) occurs in a solution containing 1×10^(−4) mol/L Ce^(3+) and 4×10^(−4) mol/L oxalate,the pH needs to be elevated from 2.0 to 3.3 to achieve the acceptable ***,findings from this study provide guidance for the obtainment of high-purity rare earth products from solutions containing a considerable amount of contaminant metal ions by means of oxalic acid precipitation.

关键词： Rare earth elements Oxalic acid Precipitation Contaminant metal ions