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Deep learning for broadleaf weed seedlings classification incorporating data variability and model flexibility across two contrasting environments

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Artificial Intelligence in Agriculture 2024年第2期12卷 29-43页

作者： lorenzo León Cristóbal Campos Juan Hirzel Instituto de Investigaciones Agropecuarias(InIA) INIA QuilamapuAvda.Vicente Méndez 515ChillánChile Fundacion ObservatorioÑuble Arauco 340ChillanChile

The increasing deployment of deep learning models for distinguishing weeds and crops has witnessed notable strides in agricultural ***,a conspicuous gap endures in the literature concerning the training and testing of models across disparate environmental *** methodologies either delineate a single dataset distribution into training,validation,and testing subsets or merge datasets from diverse condi-tions or distributions before their division into the *** study aims to ameliorate this gap by extending to several broadleaf weed categories across varied distributions,evaluating the impact of training convolutional neural networks on datasets specific to particular conditions or distributions,and assessing their performance in entirely distinct settings through three *** evaluating diverse network architectures and training approaches(finetuning versus feature extraction),testing various architectures,employing different training strategies,and amalgamating data,we devised straightforward guidelines to ensure the model's deployability in contrasting environments with sustained precision and *** Experiment 1,conducted in a uniform environment,accuracy ranged from 80%to 100%across all models and training strategies,with finetune mode achieving a superior performance of 94%to 99.9%compared to the feature extraction mode at 80%to 92.96%.Experiment 2 underscored a significant performance decline,with accuracy fig-ures between 25%and 60%,primarily at 40%,when the origin of the test data deviated from the train and valida-tion *** 3,spotlighting dataset and distribution amalgamation,yielded promising accuracy metrics,notably a peak of 99.6%for Resnet in finetuning mode to a low of 69.9%for InceptionV3 in feature extraction *** pivotal findings emphasize that merging data from diverse distributions,coupled with finetuned training on advanced architectures like Resnet and Mobilenet,markedly enhances

关键词： Artificial neural networks Deep learning Transfer learning Precision farming Feature extraction Finetuning Generalization Out-of-domain distribution Domain adaptation Multi-domain learning

Organic matter quality of forest floor as a driver of C and P dynamics in acacia and eucalypt plantations established on a Ferralic Arenosols, Congo

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Forest Ecosystems 2020年第3期7卷 511-525页

作者： Lydie-Stella Koutika lorenzo Cafiero Annamaria Bevivino Agustín Merino Research Centre on the Durability and the Productivity of Industrial Plantations(CRDPI) Av.Ma Loango Moe Poaty BP 1291Pointe-NoireRepublic of the Congo Department for Sustainability Biotechnologies and Agroindustry DivisionLaboratory for AgriFood SustainabilityQuality and SafetyItalian National Agency for New TechnologiesEnergy and Sustainable Economic DevelopmentENEACasaccia Research CentreVia Anguillarese301-00123RomeItaly Department for Sustainability Division Resource EfficiencyLaboratory Technologies for the ReuseRecyclingRecovery and valorisation of Waste and MaterialsItalian National Agency for New TechnologiesEnergy and Sustainable Economic DevelopmentENEACasaccia Research Centre00123RomeItaly Department of Soil Science and Agricultural Chemistry University of Santiago de Compostela2702LugoSpain

Background: Land-use change and forest management may alter soil organic matter(SOM) and nutrient dynamics,due in part to alterations in litter input and quality. Acacia was introduced in eucalypt plantations established in the Congolese coastal plains to improve soil fertility and tree growth. Eucalypt trees were expected to benefit from n2 fixed by acacia. However, some indicators suggest a perturbation in SOM and P dynamics might affect the sustainability of the system in the medium and long term. In tropical environments, most of the nutrient processes are determined by the high rates of organic matter(OM) mineralization. Therefore, SOM stability might play a crucial role in regulating soil-plant processes. In spite of this, the relationship between SOM quality, C and other nutrient dynamics are not well understood. In the present study, OM quality and P forms in forest floor and soil were investigated to get more insight on the C and P dynamics useful to sustainable management of forest ***: Thermal analysis(differential scanning calorimetry(DSC) and thermogravimetry(TGA)) and nuclear magnetic resonance(solid state13 C CPMASS and nMR and31 P-nMR) spectroscopy have been applied to partially decomposed forest floor and soils of pure acacia and eucalypt, and mixed-species acacia-eucalypt ***: Thermal analysis and13 C nMR analysis revealed a more advanced stage of humification in forest floor of acacia-eucalypt stands, suggesting a greater microbial activity in its litter. SOM were related to the OM recalcitrance of the forest floor, indicating this higher microbial activity of the forest floor in this stand might be favouring the incorporation of C into the mineral ***: In relation with the fast mineralization in this environment, highly soluble orthophosphate was the dominant P form in both forest floor and soils. However, the mixed-species forest stands immobilized greater P in organic forms, preventing the P losses by lea

关键词： Mixed-species plantations Soil chemical stability Organic P Forest ecosystems Potential climate change mitigation

Prevention of late complications with coverage agents in endoscopic resection of colorectal lesions: Current landscape in gastrointestinal endoscopy

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World Journal of Gastroenterology 2021年第15期27卷 1563-1568页

作者： Vicente lorenzo-Zúñiga Marco Bustamante-Balén Vicente Pons-Beltrán Endoscopy Unit Department of GastroenterologyHospital Universitari i Politècnic La FeValencia 46026Spain Digestive Diseases Department La Fe Polytechnic University HospitalValencia 46026Spain

Endoscopic removal of large(≥20 mm)non-pedunculated colorectal lesions(LnPCLs)may result in major adverse events,such as delayed bleeding(DB)and delayed perforation(DP),despite closure of the mucosal defects with *** application of a coverage agent refers to the creation of a shield with a biocompatible medical device(tissue or hydrogel)with proven bioactive *** of the eschar after endoscopic resection provides shielding protection to prevent delayed *** aim of the present review was to systematically collect and review the currently available literature regarding the prevention of DB and DP with coverage agents after endoscopic mucosal resection or endoscopic submucosal dissection of LnPCLs.

关键词： Large colorectal lesions Delayed bleeding Topical application Endoscopic mucosal resection Endoscopic submucosal dissection

Computer vision based eyewear selector

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第2期11卷 79-91页

作者： Oscar DénIZ Modesto CASTRILLón Javier lorenzo Luis AnTón Mario HERnAnDEZ Gloria BUEnO Instituto Universitario de Sistemas Inteligentes y Aplicaciones numéricas en Ingeniería Universidad de Las Palmas deGran CanariaEdificio Central del Parque Científico-Tecnológico 35017 Las Palmas E.T.S. Ingenieros Industriales Universidad de Castilla-La Mancha Campus UniversitarioAvda. Camilo José Cela

The widespread availability of portable computing power and inexpensive digital cameras are opening up new possibilities for retailers in some markets. One example is in optical shops,where a number of systems exist that facilitate eyeglassess election. These systems are now more necessary as the market is saturated with an increasingly complex array of lenses,frames,coatings,tints,photochromic and polarizing treatments,etc. Research challenges encompass Computer Vision,Multimedia andHuman-Computer Interaction. Cost factors are also of importance for widespread product acceptance. This paper describes alow-cost system that allows the user to visualize different glasses models in live video. The user can also move the glasses toadjust its position on the face. The system,which runs at 9.5 frames/s on general-purpose hardware,has a homeostatic modulethat keeps image parameters controlled. This is achieved by using a camera with motorized zoom,iris,white balance,etc. Thisfeature can be specially useful in environments with changing illumination and shadows,like in an optical shop. The system alsoincludes a face and eye detection module and a glasses management module.

关键词： Face detection. Eve detection Perceptual user interfaces Human-computer interaction

Pyrenetetraone-based covalent organic framework as an effective electrocatalyst for oxygen reduction reaction

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nano Research 2022年第5期15卷 3907-3912页

作者： Paloma Garcia-Arroyo Emiliano Martinez-Perinan Jorge J.Cabrera-Trujillo Elena Salagre Enrique G.Michel Jose I.Martinez encarnaci.n lorenzo Jose L.Segura Departamento de Quimica Organica I Facultad de CC.QuimicasUniversidad Complutense de Madrid28040 MadridSpain Departamento de Quimica Analitica y Analisis Instrumental Facultad de CienciasUniversidad Autónoma de Madrid28049 MadridSpain Departamento de Fisica de la Materia Condensada Universidad Autónoma de Madrid28049 MadridSpain Condensed Matter Physics Center(IFIMAC) Universidad Autónoma de Madrid28049 MadridSpain Departamento de nanoestructuras SuperficiesRecubrimientos y Astrofisica MolecularInstituto de Ciencia de Materiales de Madrid(ICMMCSIC)28049 MadridSpain Instituto Madrileno de Estudios Avanzados en nanociencia(IMDEA-nanociencia) 28049 MadridSpain Institute for Advanced Research in Chemical Sciences(IAdChem) Universidad Autonoma de Madrid28049 MadridSpain

A novel porous and crystalline two-dimensional(2D)electrochemically active covalent organic framework(COF)based on ortho-quinone units has been prepared as an innovative approach towards the development of organic cathode materials with multiple redox sites as an efficient electrocatalyst for the oxygen reduction reaction(ORR).In contrast with most of the previously reported COFs as electrocatalysts for the ORR,the electrocatalytic application of this material towards ORR has been investigated without adding any metal or conductive supporting material and avoiding any additional carbonization ***,the electrochemical properties of the COF material have been compared with two analogue amorphous frameworks with similar chemical composition,which points out the important role of the enhanced crystallinity and porosity of the COF network in its superior performance as an electrocatalyst towards ORR.

关键词： electrocatalysis oxygen reduction reaction metal free pyrenetetraone covalent organic framework

Seismic displacement demand prediction in non-linear domain: Optimization of the n2 method

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Earthquake Engineering and Engineering Vibration 2019年第1期18卷 141-158页

作者： lorenzo Diana Andrea Manno Pierino Lestuzzi EPFL – EnAC – IIC – IMAC DEIB Politecnico di Milano

In Europe, computation of displacement demand for seismic assessment of existing buildings is essentially based on a simplified formulation of the n2 method as prescribed by Eurocode 8(EC8). However, a lack of accuracy of the n2 method in certain conditions has been pointed out by several studies. This paper addresses the assessment of effectiveness of the n2 method in seismic displacement demand determination in non-linear domain. The objective of this work is to investigate the accuracy of the n2 method through comparison with displacement demands computed using non-linear timehistory analysis(nLTHA). Results show that the original n2 method may lead to overestimation or underestimation of displacement demand predictions. This may affect results of mechanical model-based assessment of seismic vulnerability at an urban scale. Hence, the second part of this paper addresses an improvement of the n2 method formula by empirical evaluation of nLTHA results based on EC8 ground-classes. This task is formulated as a mathematical programming problem in which coefficients are obtained by minimizing the overall discrepancy between nLTHA and modified formula results. Various settings of the mathematical programming problem have been solved using a global optimization metaheuristic. An extensive comparison between the original n2 method formulation and optimized formulae highlights benefits of the strategy.

关键词： n2 method seismic vulnerability assessment non-linear time-history analysis spectrum compatible recordings displacement demand determination optimization strength reduction factor

UV and soft x-ray emission from gaseous and solid targets employing SiC detectors

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Plasma Science and Technology 2021年第5期23卷 147-154页

作者： Alfio TORRISI Przemysław WACHULAK lorenzo TORRISI CEDAD-Dept.of Mathematics and Physics‘E.De Giorgi’ University of SalentoLecce 73100Italy Institute of Optoelectronics Military University of TechnologyWarsaw 00-908Poland Dept.of Mathematical and Computer Sciences Physical Sciences and Earth Sciences(MIFT)-University of MessinaMessina 98166Italy

A ns nd:YAG pulsed laser has been employed to produce plasma from the interaction with a dense target,generating continuum and UV and soft x-ray emission depending on the laser parameters and target *** laser hits solid and gaseous targets producing plasma in high vacuum,which was investigated by employing a silicon carbide *** two different interaction mechanisms were studied,as well as their dependence on the atomic *** photon emission from laser-generated plasma produced by solid targets,such as boron nitride(Bn)and other elements(Al,Cu,Sn and Ta)and compounds such as polyethylene,has been compared with that coming from plasma produced by irradiating different gas-puff targets based on n_(2)and other gases(Ar,Xe,Kr,SF_(6)).The experimental results demonstrated that the yields are comparable and,in both cases,increase proportionally to the target atomic *** obtained results,focusing the attention on the advantages and drawbacks of the employed targets,are presented and discussed.

关键词： laser-matter interaction plasma diagnostics SiC detectors

Biodegradable stents in gastrointestinal endoscopy

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World Journal of Gastroenterology 2014年第9期20卷 2212-2217页

作者： Vicente lorenzo-Zú?iga Vicente Moreno-de-Vega Ingrid Marín Jaume Boix Endoscopy Unit Department of Gastroenterology Hospital Universitari Germans Trias i Pujol 08916 Badalona Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD) 08916 Badalona Spain

Biodegradable stents(BDSs)are an attractive option to avoid ongoing dilation or surgery in patients with benign stenoses of the small and large *** experience with the currently the only BDS for endoscopic placement,made of Poly-dioxanone,have shown promising *** some aspects should be improved as are the fact that BDSs lose their radial force over time due to the degradable material,and that can cause stent-induced mucosal or parenchymal *** complication rate and modest clinical efficacy has to be carefully considered in individual patients prior to placement of ***,the price of these stents therefore it is nowadays an important limitation.

关键词： Biodegradable stents Strictures Endoscopy Endoscopic placement Stenoses

Strongly Convergent Approximations to Fixed Points of Total Asymptotically nonexpansive Mappings

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Acta Mathematica Sinica,English Series 2008年第6期24卷 1005-1022页

作者： Yakov ALBER Rafa ESPínOLA Pepa lorenzo Department of Mathematics The Technion-Israel Institute of Technology32000 HaifaIsrael Departamento de Andlisis Matemdtico Universidad de SevillaP.O.Box 116041080-SevilleSpain

In this work we prove a new strong convergence result of the regularized successive approximation method given by yn＋1 = qnz0 ＋（1 - qn）T^nyn, n = 1, 2,…,where lim n→∞ qn = 0 and ∞∑n=1 qn=∞ for T a total asymptotically nonexpansive mapping, i.e., T is such that ││T^n x - T^n y││ ≤ x - y ││ ＋ kn^（1）φ（││x - y││）＋ kn^（2）,where kn^1 and kn^2 are real null convergent sequences and φ：R^＋→R^＋ is continuous such that φ（0）=0 and limt→∞φ（t）/t≤ C for a certain constant C 〉 0. Among other features, our results essentially generalize existing results on strong convergence for T nonexpansive and asymptotically nonexpansive. The convergence and stability analysis is given for both self- and nonself-mappings.

关键词： asymptotically nonexpansive mappings best approximation fixed point duality map iteration schemes