检索结果-南通市图书馆

What diameter?What height?Influence of measures of average tree size on area-based allometric volume relationships

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

forest Ecosystems 2024年第1期11卷 100-109页

作者： Yilin Wang John A.Kershaw Mark J.Ducey Yuan Sun james B.McCarter Integrated forest Mensuration and Systems Analysis Laboratory Faculty of Forestry and Environmental ManagementUniversity of New BrunswickFrederictonNBCanada Department of Natural Resources and the Environment University of New HampshireDurhamNHUSA College of forestry Nanjing Forestry UniversityNanjing210037China Scientific Programmer RayonierYuleeFLUSA

Volume is an important attribute used in many forest management *** from 83 fixed-area plots located in central New Brunswick,Canada,are used to examine how different measures of stand-level diameter and height influence volume prediction using a stand-level variant of Honer's(1967)volume *** density was included in the models(Volume=f(Diameter,Height,Density))choice of diameter measure was more important than choice of height *** density was not included(Volume=f(Diameter,Height)),the opposite was *** models with density included,moment-based estimators of stand diameter and height performed better than all other *** models without density,largest tree estimators of stand diameter and height performed better than other *** overall best equation used quadratic mean diameter,Lorey's height,and density(root mean square error=5.26 m^3·ha^(-1);1.9%relative error).The best equation without density used mean diameter of the largest trees needed to calculate a stand density index of 400 and the mean height of the tallest 400 trees per ha(root mean square error=32.08 m^(3)·ha^(-1);11.8%relative error).The results of this study have some important implications for height subsampling and LiDAR-derived forest inventory analyses.

关键词： Allometric relationships Stand structure Volume estimation Stand-level attributes

Comparing four machine learning algorithms for household non-intrusive load monitoring

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Energy and AI 2024年第3期17卷 206-219页

作者： Thomas Lee Young james Gopsill Maria Valero Sindre Eikevåg Ben Hicks University of Bristol UK

The combination of Machine Learning (ML), smart energy meters, and availability of household appliance energy profile data has opened new opportunities for Non-Intrusive Load Monitoring (NILM). However, the number of options makes it challenging in selecting optimal combinations for different energy applications, which requires studies to examine their *** paper contributes one such study that investigated four established ML approaches – K Nearest Neighbour (KNN), Support Vector Machine (SVM), eXtreme Gradient Boosting (XGBoost) and Convolutional Neural Network (CNN) – and their performance in classifying appliance events from Alternating Current (AC) and Root Mean Square (RMS) energy data where the sampling frequency and training dataset set size was varied (10 Hz–1 kHz and 50–2000 examples per class, respectively). The computational expense during training, testing and storage was also assessed and evaluated with reference to real-world *** CNN classifier trained on AC data at 500 Hz and 11,000 examples gave the best f1-score (0.989) followed by the KNN classifier (0.940). The storage size required by the CNN models was 3̃MB, which is very close to fitting on cost-effective embedded system microcontrollers. This would prevent high-rate data needing to be sent to the cloud as analysis could be performed on edge computing Internet-of-Things (IoT) devices.

关键词： NILM ML Edge computing Signal processing Smart meters

Ranking environmental and edaphic attributes driving soil microbial community structure and activity with special attention to spatial and temporal scales

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

mLife 2024年第1期3卷 21-41页

作者： Vadakattu V.S.R.Gupta james M.Tiedje CSIRO Agriculture&food UrrbraeSouth AustraliaAustralia Centre for Microbial Ecology Michigan State UniversityEast LansingMichiganUSA

The incredibly complex soil microbial communities at small scales make their analysis and identification of reasons for the observed structures *** community structure is mainly a result of the inoculum(dispersal),the selective advantages of those organisms under the habitat-based environmental attributes,and the ability of those colonizers to sustain themselves over *** soil is protective,and its microbial inhabitants have long adapted to varied soil conditions,significant portions of the soil microbial community structure are likely ***,a substantial portion of the community will not correlate to often measured soil *** suggest that the drivers be ranked on the basis of their importance to the fundamental needs of the microbes:(i)those that supply energy,i.e.,organic carbon and electron acceptors;(i)environmental effectors or stressors,i.e.,pH,salt,drought,and toxic chemicals;(ii)macro-organism associations,i.e.,plants and their seasonality,animals and their fecal matter,and soil fauna;and(iv)nutrients,in order,N,P,and probably of lesser importance,other micronutrients,and *** relevance of drivers also varies with spatial and time scales,for example,aggregate to field to regional,and persistent to dynamic populations to transcripts,and with the extent of phylogenetic difference,hence phenotypic differences in organismal *** present a summary matrix to provide guidance on which drivers are important for particular studies,with special emphasis on a wide range of spatial and temporal scales,and illustrate this with genomic and population(rRNA gene)data from selected studies.

关键词： abundance community structure diversity functional microbiome microorganisms

Competitive interactions and coexistence of sympatric flagship carnivores in Asia

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Integrative Zoology 2024年第2期19卷 183-199页

作者： Zhilin LI Jiayu LU Xiaoyi SHI Li’an DUO james L.D.SMITH Tianming WANG Tianjin Key Laboratory of Conservation and Utilization of Animal Diversity College of Life SciencesTianjin Normal UniversityTianjinChina Department of fisheries Wildlife and Conservation BiologyUniversity of MinnesotaSt.PaulMinnesotaUSA Ministry of Education Key Laboratory for Biodiversity Science and Engineering College of Life SciencesBeijing Normal UniversityBeijingChina National forestry and Grassland Administration Key Laboratory for Conservation Ecology of Northeast Tiger and Leopard BeijingChina

Understanding the competition and coexistence of flagship carnivores is key to creating strategies for their conservation in the face of global carnivore *** studies exploring the dynamics and competition between tigers(Panthera tigris)and leopards(***)span decades,there is a lack of understanding regarding the factors that influence their coexistence mechanisms on a broad scale,as well as the drivers determining their exploitative and interference *** gathered a comprehensive list of research papers among which 36 papers explored the interspecific interactions between tigers and leopards and tested the influence of biotic and abiotic factors on the coexistence mechanisms along three dimensions using multiple response variables regression models;we also tested the influence of ecological drivers determining the exploitative or interference competition between tigers and *** and ungulate density were the most important predictors in regulating the coexistence *** and leopards exhibited more positive relations/higher overlaps as elevation increased in the spatial *** addition,they showed a higher dietary overlap in the prey-rich *** determined that interference competition between tigers and leopards was less frequently observed in habitats with dense tree cover and homogeneous vegetation ***,studies with multiple metrics would promote the detection of interference *** study provides new insight into the competitive interactions and coexistence mechanisms of tigers and leopards on a broad ***-makers and managers should pay more attention to the factors of elevation,prey abundance,and habitat structures for the conservation of tigers and leopards.

关键词： carnivores coexistence mechanisms competitive interactions exploitative competition interference competition

Cross-comparative review of Machine learning for plant disease detection:apple,cassava,cotton and potato plants

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Artificial Intelligence in Agriculture 2024年第2期12卷 127-151页

作者： james Daniel Omaye Emeka Ogbuju Grace Ataguba Oluwayemisi Jaiyeoba Joseph Aneke francisca Oladipo Department of Computer Science Federal UniversityLokojaNigeria Department of Computer Science Dalhousie UniversityHalifaxCanada Department of Computer Science Hampton UniversityVirginiaUSA

Plant disease detection has played a significant role in combating plant diseases that pose a threat to global agri-culture and food *** these diseases early can help mitigate their impact and ensure healthy crop *** learning algorithms have emerged as powerful tools for accurately identifying and classifying a wide range of plant diseases from trained image datasets of affected *** algorithms,including deep learning algorithms,have shown remarkable success in recognizing disease patterns and early signs of plant *** early detection,there are other potential benefits of machine learning algorithms in overall plant disease management,such as soil and climatic condition predictions for plants,pest identification,proximity detection,and many *** the years,research has focused on using machine-learning algorithms for plant disease ***,little is known about the extent to which the research community has ex-plored machine learning algorithms to cover other significant areas of plant disease *** view of this,we present a cross-comparative review of machine learning algorithms and applications designed for plant dis-ease detection with a specific focus on four(4)economically important plants:apple,cassava,cotton,and *** conducted a systematic review of articles published between 2013 and 2023 to explore trends in the research community over the *** filtering a number of articles based on our inclusion criteria,including articles that present individual prediction accuracy for classes of disease associated with the selected plants,113 articles were considered *** these articles,we analyzed the state-of-the-art techniques,challenges,and future prospects of using machine learning for disease identification of the selected *** from our re-view show that deep learning and other algorithms performed significantly well in detecting plant *** addition,we fou

关键词： Machine learning Plant diseases Agriculture Plant disease management Convolutional neural networks

Enhancing hourly heat demand prediction through artificial neural networks:A national level case study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy and AI 2024年第1期15卷 288-299页

作者： Meng Zhang Michael-Allan Millar Si Chen Yaxing Ren Zhibin Yu james Yu james Watt School of Engineering University of GlasgowGlasgowG128QQUK University of Lincoln Brayford PoolLincolnLN67TSUK Scottish Power GlasgowG28DQUK

Meeting the goal of zero emissions in the energy sector by 2050 requires accurate prediction of energy consumption,which is increasingly ***,conventional bottom-up model-based heat demand forecasting methods are not suitable for large-scale,high-resolution,and fast forecasting due to their complexity and the difficulty in obtaining model *** paper presents an artificial neural network(ANN)model to predict hourly heat demand on a national level,which replaces the traditional bottom-up model based on extensive building simulations and *** ANN model significantly reduces prediction time and complexity by reducing the number of model input types through feature selection,making the model more realistic by removing non-essential *** improved model can be trained using fewer meteorological data types and insufficient data,while accurately forecasting the hourly heat demand throughout the year within an acceptable error *** model provides a framework to obtain accurate heat demand predictions for large-scale areas,which can be used as a reference for stakeholders,especially policymakers,to make informed decisions.

关键词： Heating demand in buildings National level forecast feature selection Machine learning Artificial neural network

Hierarchical crystalline-amorphous nanocomposites with high strength and large deformability enabled by elemental diffusion

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第4期171卷 150-161页

作者： Liqiang Wang Heyi Wang Xin Zhou Huangliu fu james Utama Surjadi Shuo Qu Xu Song Rong fan Yang Lu Department of Mechanical Engineering City University of Hong KongHong KongChina Nano-Manufacturing Laboratory(NML) Shenzhen Research Institute of City University of Hong KongShenzhen 518057China Chengdu Research Institute City University of Hong KongChengdu 610200China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Mechanical and Automation Engineering The Chinese University of Hong KongHong KongChina Department of Mechanical Engineering The University of Hong KongHong KongChina

Amorphous/nanocrystalline dual-phase structures have recently emerged as an effective way for over-coming the strength-ductility trade-offand breaking the limitation of the reverse Hall-Petch ***,we proposed a new strategy to develop a hierarchical and interconnected amorphous-crystalline nanocomposite arising from the nanoscale elemental interdiffusion and oxygen adsorption behavior dur-ing thermal treatment *** nanocomposite consisted of a three-dimensional(3D)hierarchical network structure where the crystalline phase(Cr-Co-Ni-Al)was embedded into the Al-O-based amor-phous phase network with critical feature sizes encompassing three orders of magnitude(from microm-eter to nanometer scale).It can achieve ultrahigh compression yield strength of-3.6 GPa with large homogeneous deformation of over 50%*** massive interstitial atoms induced lattice distortion and hierarchical amorphous phase boundary contributed to the strength *** situ Uniaxial compression inside a transmission electron microscope(TEM)revealed that the exceptional deformability of the nanocomposites resulted from the homogenous plastic flow of nano-sized amorphous phase and the plastic co-deformation behavior restricted by the nano-architected dual-phase *** proposed dual-phase synthesis approach can outperform conventional nanolaminates design strategies in terms of the mechanical properties achievable while providing a pathway to easily tune the microstructure of these nanolaminates.

关键词： Nanolaminates Dual-phase nanocomposites In situ transmission electron microscopy Multi-component alloy

A Dark Energy Hypothesis II

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of High Energy Physics, Gravitation and Cosmology 2024年第3期10卷 1142-1151页

作者： james Togeas University of Minnesota Morris Campus Morris USA

The article develops a cosmological model based on a hypothesis that dark energy is a cosmological variable rather than a constant. A companion paper (DEH I) derives a formula for this variable cosmological parameter as well as an argument that the early universe produces it and dark matter. The developed model leads to a series of self-consistent results including a prediction that provides a test for it. The results include comparisons of the DEH and the ΛCDM theory.

关键词： Dark Energy Dark Matter Cosmological Constant Coupling of Space and Time

How to fill the biodiversity data gap:Is it better to invest in fieldwork or curation?

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plant Diversity 2024年第1期46卷 39-48页

作者： Carlos A.Vargas Marius Bottin Tiina Sarkinen james E.Richardson Marcela Celis Boris Villanueva Adriana Sanchez Programa de Biología Facultad de Ciencias NaturalesUniversidad del RosarioBogotaD.C.Colombia Subdireccion Científica Jardín Botanico de Bogota“Jose Celestino Mutis”BogotaD.C.Colombia Independent Researcher BogotaD.C.Colombia Tropical Diversity Section Royal Botanic Garden EdinburghUK School of Biological Earth and Environmental SciencesUniversity College CorkCorkIreland Departamento de Química y Biología Universidad del NorteKm.5 Vía Puerto ColombiaArea Metropolitana de Barranquilla 081007Colombia

Data gaps and biases are two important issues that affect the quality of biodiversity information and downstream *** how best to fill existing gaps and account for biases is necessary to improve our current information most *** current main approaches for obtaining and improving data include(1)curation of biological collections,and(2)***,the comparative effectiveness of these approaches in improving biodiversity data remains little *** used the flora de Bogota project to study the magnitude of change in species richness,spatial coverage,and sample coverage of plant records based on curation versus *** process of curation resulted in a decrease in species richness(synonym and error removal),but it significantly increased the number of records per *** contributed to a slight increase in species richness,via accumulation of new ***,curation led to increases in spatial coverage,species observed by locality,the number of plant records by species,and localities by species compared to ***,curationwas more efficient in producing new information compared to fieldwork,mainly because of the large number of records available in *** recommend intensive curatorial work as the first step in increasing biodiversity data quality and quantity,to identify bias and gaps at the regional scale that can then be targeted with *** stepwise strategy would enable fieldwork to be planned more costeffectively given the limited resources for biodiversity exploration and characterization.

关键词： Colombia flora de Bogota Sample coverage Species richness Tropical Andes