检索结果-南通市图书馆

Apparent soil electrical conductivity in the delineation of management zones for cocoa cultivation

Information Processing in Agriculture 2022年第3期9卷 443-455页

作者： Samuel de Assis Silva Railton Oliveira dos santos Daniel Marcal de Queiroz Juliao Soares de Souza Lima Levi Fraga Pajehua Caique Carvalho Medauar Center for Agricultural Sciences and Engineering Federal University of Espirito SantoAlegre CampusEspirito Santo 29500-000Brazil Department of Agricultural Sciences Santa Cruz State UniversityIlheusBahia 45662-900Brazil Department of Agricultural Engineering Federal University of Vic¸osaVic¸osaMinas Gerais 36570-900Brazil

Apparent electrical conductivity is an important parameter for describing the spatial vari-ability of physical and chemical attributes of the soil and for the delineation of manage-ment *** objective of this work is to outline management zones for the cocoa cultivation based on the spatial variability of the productivity and the apparent electrical conductivity(ECa)of the *** collection was performed in a regular sample grid con-taining 120 points in an area cultivated with cocoa trees,located in the municipality of Ilhe´us,state of Bahia,*** each sampling point(cocoa tree),soil samples were col-lected to determine chemical *** was measured for one year,counting,monthly,the number of fruits,which were classified into off-season cocoa,harvest and annual *** of the apparent electrical conductivity of the soil were performed at different times of the year using a portable conductivity *** data were analyzed using classical statistics and *** management zones were delin-eated using the fuzzy k-means *** ideal number of class was defined using the fuzziness performance index(FPI)and the entropy of the modified partition(MPE)*** Kappa coefficient was used to validate the management zones,assessing their agreement with the chemical attributes of the *** ECa of the soil values pre-sented moderate temporal variation,with maximum amplitude of 19.37 mS m1 and min-imum of 0.82 mS m1 between measurement periods;higher averages of the ECa coincided with the highest levels of water in the *** measurements of the ECa of the soil carried out in April and October showed greater correlation with the chemical attributes of the soil,with significant values for 11 and 8 of the 17 attributes evaluated,*** man-agement zones from the ECa measured in April showed:a)reduced number of classes;b)spatial continuity between classes,and;c)agreement from reasonable(kappa between

关键词： Theobroma cacao Precision agriculture Spatial variability Fuzzy k-means

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Proposals of SPT-CPT and DPL-CPT correlations for sandy soils in Brazil

引用

Journal of Rock Mechanics and Geotechnical Engineering 2017年第6期9卷 1152-1158页

作者： Mirella Dalvi dos santos Kátia Vanessa Bicalho Universidade Federal do Espírito Santo VitóriaBrazil

Field tests in geotechnical engineering are fundamental for identification of the underground *** standard penetration test(SPT) is the most commonly used geotechnical approach. There has been an increase both in the use and application of the in situ tests: cone penetration test(CPT) and dynamic probing(DP). Several empirical SPT-CPT and dynamic probing light(DPL)-CPT correlations for sandy soils have been discussed in the literature. New SPT-CPT and DPL-CPT correlations for the sandy soils of the city of Vitoria, in the southeast of Brazil, are suggested in this paper. Statistical analyses to evaluate the quality of the data used are performed, and the suggested correlations are validated with several previous published datasets. The paper also provides some insights into SPT-CPT correlations and soil characteristics(i.e. the mean particle size and the fines fraction of the soil).

关键词： Standard penetration test(SPT) Cone penetration test(CPT) Dynamic probing light(DPL) Correlations Sands Statistical evaluations

来源：

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

Gender inequalities in physical activity among adolescents from 64 Global South countries

引用

Journal of Sport and Health Science 2022年第4期11卷 509-520页

作者： Luiza Isnardi Cardoso Ricardo Andrea Wendt Caroline dos santos Costa Gregore Iven Mielke Javier Brazo-Sayavera Asaduzzaman Khan Tracy L Kolbe-Alexander Inacio Crochemore-Silva Federal University of Pelotas PelotasRS 96010-040Brazil University of Sao Paulo Sao PauloSP 01153-000Brazil School of Public Health The University of QueenslandHerstonQLD 4006Australia University of the Republic MontevideoMontevideo 11200Uruguay

Purpose:The aims of this study were to(a)describe gender inequalities in physical activity(PA)among adolescents from Global South countries,and(b)investigate the relationship between gender inequalities in PA and contextual factors,such as geographic region,human development index,gender inequality index,and unemployment ***:We analyzed cross-sectional data from the Global School-Based Student Health Survey conducted in Global South countries between 2010 and 2020 among 13-to 17-year-old ***-context variables were retrieved from secondary data sources(World Health Organization,World Bank,and Human Development Reports).PA was assessed by a self-administered questionnaire querying the number of days in the past week in which participants were physically active for a total of at least 60 *** absolute gender inequalities were evaluated by the differences in the prevalence between boys and girls,95%confidence intervals(95%CIs)were estimated using the bootstrap *** inequalities were obtained through Poisson ***-analyses with random effects were used to calculate pooled estimates of absolute and relative ***:Based on 64 Global South countries/surveys,the prevalence of PA was 6.7 percentage points(p.p.)higher in boys than in girls,ranging from 0.5 *** Afghanistan to 15.6 *** Laos(I^(2)=85.1%).The pooled ratio for all countries showed that boys presented a PA prevalence 1.58 times higher than girls(95%CI:1.47-1.70)on *** highest absolute and relative inequalities were observed in high income *** with higher Human Development Index rankings and lower Gender Inequality Index rankings also presented greater gender ***:Given that girls are overall less active than boys across the globe,the findings of this study reinforce that macro-and micro-level changes should be actively sought if we aim to increase population levels of PA in adolescents and promote equity i

关键词： Adolescents Gender differences Physical activity Social inequalities Students

来源：

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

Building capabilities in natural resource-dependent economies:An innovation systems analysis of the TVET program in Guyana

引用

International Journal of Innovation Studies 2019年第1期3卷 1-11页

作者： Chantal dos santos Friedrich-Alexander University Erlangen-Nuremberg 91054 ErlangenGermany

This paper examines Guyana's technical and vocational education and training(TVET)system in relation to diversifying the country's economy away from natural resource *** innovation systems approach is used to examine the effectiveness of TVET as a means of building capabilities in Guyana's key industries,gold and sugar,providing a snapshot of the state of the system in early,*** interviewees across several areas of expertise were consulted in Georgetown,*** analysis of primary and secondary research finds TVET's effectiveness to be limited by a lack of labor market information and funding,energy costs,a“brain drain”,and insufficient information communication technology skills and *** remedies include increasing the frequency of labor market surveys,attracting the Guyanese diaspora back to share knowledge,reducing the cost of energy by taking advantage of domestic renewable energy potential,and setting up a Sovereign Wealth Fund.

关键词： Innovation systems Guyana CARICOM Natural resources TVET

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Finite Difference Method Applied in Two-Dimensional Heat Conduction Problem in the Permanent Regime in Rectangular Coordinates

引用

Advances in Pure Mathematics 2022年第9期12卷 505-518页

作者： Vânia Gonçalves de Brito dos santos Paula Tamires Gomes dos Anjos Departamento de Ciências Exatas e da Terra Universidade do Estado da Bahia (UNEB) Salvador Brazil Centro Educacional Expoente (CEDEX) Brasília Brazil

The solution of many conduction heat transfer problems is found by two-dimensional simplification using the analytical method since different points have different initial temperatures. The temperature at each point of a given element can be analyzed through the Heat Equation that, in some cases, converges to analytical solutions without precision and is far from the real. However, with the application of the Finite Difference Method (FDM), it is possible to solve it numerically in a relatively fast way, providing satisfactory results for the most varied boundary conditions and diverse geometries, characteristics of heat transfer problems by conduction. This study solved two problems inside a plate with and without heat generation involved in temperature distribution. Algorithms were built with the aid of the Matlab programming language, and applied to obtain a numerical solution using the FDM numerical method. The computational and analytical solutions were then compared. Under certain conditions of the parameters involved in the phenomenon of each problem, the numerical method was very efficient for presenting errors less than or equal to 0.003 and 0.03, respectively, for cases without and with heat generation.

关键词： Heat Transfer Conduction Finite Difference Method Numerical Method Matlab

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A Numerical Comparison Between Quasi-Monte Carlo and Sparse Grid Stochastic Collocation Methods

引用

Communications in Computational Physics 2012年第9期12卷 1051-1069页

作者： Juarez dos santos Azevedo Saulo Pomponet Oliveira CETEC-UFRB Centro44380-000Cruz das Almas-BABrazil.2 DMAT-UFPRCentro Politecnico81531-980Curitiba-PRBrazil

Quasi-Monte Carlo methods and stochastic collocation methods based on sparse grids have become popular with solving stochastic partial differential *** methods use deterministic points for multi-dimensional integration or interpolation without suffering from the curse of *** is not evident which method is best,specially on random models of physical *** numerically study the error of quasi-Monte Carlo and sparse gridmethods in the context of groundwater flow in heterogeneous *** particular,we consider the dependence of the variance error on the stochastic dimension and the number of samples/collocation points for steady flow problems in which the hydraulic conductivity is a lognormal *** suitability of each technique is identified in terms of computational cost and error tolerance.

关键词： Karhunen-Loève expansion Monte Carlo quasi-Monte Carlo sparse grid

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Changes on Anuran Tadpole Functional Diversity along an Environmental Gradient at the Southernmost Atlantic Rainforest Remnant

引用

Asian Herpetological Research 2020年第1期11卷 63-70页

作者： Victor Mendes LIPINSKI Andre Passaglia SCHUCH Tiago Gomes dos santos Post Graduation Program of Animal Biodiversity Federal University of Santa MariaLaboratory of HerpetologyDepartment of BiologyAv.Roraima no 1000 building 17room 1140Camobi97105-900Santa MariaRSBrazil Universidade Federal do Pampa Av.Antonio Trilha1847Centro973000000 Sao GabrielRSBrasil Southern Regional Space Research Center CRS/INPE-MCTIP.O.Box 5021room 104197110-970Santa MariaRSBrazil

For decades the ecologists are using the same methods in order to determine the environmental health of a community,however,the crescent need on defining how these processes act,triggered the development of new methods that could classify the organisms and their function at the *** we used the anuran larvae to understand the effects of an environmental gradient on the structure and organization of the anuran assemblages along it,and to access in a realistic form,the actual state of preservation of the la rgest remnant of Atlantic Rainforest on the Southernmost portion of *** found that despite the higher diversity of species and the conservation unit status of the place,the ecosystem itself is still in danger,given the low number of functional groups and thus a higher number of ecosystem services that can be lost.

关键词： Anuran ecosystem function conservation unities tadpoles

来源：

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

Gut-microbiome-brain axis:the crosstalk between the vagus nerve,alpha-synuclein and the brain in Parkinson's disease

引用

Neural Regeneration Research 2023年第12期18卷 2611-2614页

作者： Júlio César Claudino dos santos Leandro Freitas Oliveira Felipe Micelli Noleto Camilla Teixeira Pinheiro Gusmão Gerly Anne de Castro Brito Glauce Socorro de Barros Viana Christus University Center-UNICHRISTUS FortalezaCEBrazil Postgraduate Program in Morphofunctional Sciences Federal University of Ceará-UFCFortalezaCEBrazil Universidade Católica de Brasília-UCB BrasíliaDFBrasil Postgraduate Program in Physiology and Pharmacology Department of the Federal University of Ceará-UFC FortalezaCEBrazil Physiology and Pharmacology Department of the Federal University of Ceará-UFC FortalezaCEBrazil

This critical review of the literature shows that there is a close link between the microbiome,the gut,and the brain in Parkinson's *** vagus nerve,the main component of the parasympathetic nervous system,is involved in the regulation of immune response,digestion,heart rate,and control of *** can detect microbiota metabolites through its afferents,transferring this gut information to the central nervous *** and clinical studies have shown the important role played by the gut microbiome and gut-related factors in disease development and progression,as well as treatment *** findings suggest that the gut microbiome may be a valuable target for new therapeutic strategies for Parkinson's *** studies are needed to better understand the underlying biology and how this axis can be modulated for the patient's benefit.

关键词： alpha-synuclein enteric microbiota gastrointestinal tract Parkinson's disease vagus nerve

来源：

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

Natural and Eco-Friendly Materials for Triboelectric Energy Harvesting

引用

Nano-Micro Letters 2020年第3期12卷 179-196页

作者： Vladislav Slabov Svitlana Kopyl Marco PSoares dos santos Andrei L.Kholkin Department of Physics and CICECO‑Aveiro Institute of Materials University of Aveiro3810‑193 AveiroPortugal Centre for Mechanical Technology and Automation(TEMA) University of Aveiro3810‑193 AveiroPortugal Department of Mechanical Engineering University of Aveiro3810‑193 AveiroPortugal School of Natural Sciences and Mathematics Ural Federal UniversityEkaterinburgRussia 620000 Laboratory of Functional Low‑Dimensional Structures National University of Science and Technology MISiSMoscowRussia 119049

Triboelectric nanogenerators(TENGs)are promising electric energy harvesting devices as they can produce renewable clean energy using mechanical excitations from the *** designs of triboelectric energy harvesters relying on biocompatible and eco-friendly natural materials have been introduced in recent *** ability to provide customizable self-powering for a wide range of applications,including biomedical devices,pressure and chemical sensors,and battery charging appliances,has been *** review summarizes major advances already achieved in the field of triboelectric energy harvesting using biocompatible and eco-friendly natural materials.A rigorous,comparative,and critical analysis of preparation and testing methods is also *** power up to 14 mW was already achieved for the dry leaf/polyvinylidene fluoride-based TENG *** findings highlight the potential of eco-friendly self-powering systems and demonstrate the unique properties of the plants to generate electric energy for multiple applications.

关键词： Natural and eco-friendly materials Energy harvesting Triboelectric nanogenerators Biocompatibility

来源：

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

TODIM and TOPSIS with Z-numbers

引用

Frontiers of Information Technology & Electronic Engineering 2019年第2期20卷 283-291页

作者： Renato A.KROHLING André G.C.PACHECO Guilherme A.dos santos Department of Production Engineering Federal University of Espirito Santo Graduate Program in Computer Science Federal University of Espirito Santo

In this paper, we present an approach that can handle Z-numbers in the context of multi-criteria decision-making problems. The concept of Z-number as an ordered pair Z=(A, B) of fuzzy numbers A and B is used, where A is a linguistic value of a variable of interest and B is a linguistic value of the probability measure of A. As human beings, we communicate with each other by means of natural language using sentences like "the journey from home to university most likely takes about half an hour." The Z-numbers are converted to fuzzy numbers. Then the Z-TODIM and Z-TOPSIS are presented as a direct extension of the fuzzy TODIM and fuzzy TOPSIS, respectively. The proposed methods are applied to two case studies and compared with the standard approach using crisp values. The results obtained show the feasibility of the approach.

关键词： Multi-criteria decision-making TODIM TOPSIS Fuzzy number Z-number

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：