Consulta: subjectFacets:"Regression"
Registros recuperados: 34
Data/hora: 02/06/2024 02:47:46

Explaining dinophysis cf. acuminata abundance in Antifer (Normandy, France) using dynamic linear regression
Provedor de dados: 5
Autores: Soudant, Dominique; Beliaeff, Benoit; Thomas, G.
Classical regression analysis can be used to model time series. However, the assumption that model parameters are constant over time is not necessarily adapted to the data. In phytoplankton ecology, the relevance of time-varying parameter values has been shown using a dynamic linear regression model (DLRM). DLRMs, belonging to the class of Bayesian dynamic models, assume the existence of a non-observable time series of model parameters, which are estimated on-line, i.e. after each observation. The aim of this paper was to show how DLRM results could be used to explain variation of a time series of phytoplankton abundance. We applied DLRM to daily concentrations of Dinophysis cf. acuminata, determined in Antifer harbour (French coast of the English...
Tipo: Text
Palavras-chave: Phytoplankton; Dinophysis; Time series; Regression; Dynamic; Bayesian.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/00337/44784/44490.pdf

Response of Arctic Freshwater to the Arctic Oscillation in Coupled Climate Models
Provedor de dados: 5
Autores: Cornish, Sam B.; Kostov, Yavor; Johnson, Helen L.; Lique, Camille.
The freshwater content (FWC) of the Arctic Ocean is intimately linked to the stratification—a physical characteristic of the Arctic Ocean with wide relevance for climate and biology. Here, we explore the relationship between atmospheric circulation and Arctic FWC across 12 different Coupled Model Intercomparison Project Phase 5 control run simulations. Using multiple lagged regression, we seek to isolate the linear response of Arctic FWC to a step change in the strength of the Arctic Oscillation (AO), as well as the second and third orthogonal modes of SLP variability over the Arctic domain. There is broad agreement amongst models that a step change to a more anticyclonic AO leads to an increase in Arctic FWC, with an e-folding timescale of five to ten...
Tipo: Text
Palavras-chave: Arctic; Arctic Oscillation; Freshwater; Statistical techniques; Regression.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00601/71270/69668.pdf

Research of quality indices for cold-smoked salmon using a stepwise multiple regression of microbiological counts and physico-chemical parameters
Provedor de dados: 5
Autores: Leroi, Francoise; Joffraud, Jean-jacques; Chevalier, Frederique; Cardinal, Mireille.
Aims: The aim of the study was to assess the relationships between the remaining shelf-life (RSL) of cold-smoked salmon and various microbiological and physico-chemical parameters, using a multivariate data analysis in the form of stepwise forward multiple regression.  Methods and Results: Thirteen batches of French cold-smoked salmon were analysed weekly during vacuum-packed storage at 5 degreesC for their lipid, water, salt, phenol, pH, total volatile basic nitrogen (TVBN) and trimethylamine contents, total psychrotrophic count, lactic acid bacteria, lactobacilli, B. thermosphacta, Enterobacteriaceae and yeast counts. At the sensory rejection time, the flora was dominated by lactobacilli, lactobacilli/Enterobacteriaceae or Carnobacteria/B. thermosphacta....
Tipo: Text
Palavras-chave: Microbiological; Parameters; Regression; Cold smoked salmon.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/publication-609.pdf

Uncertainties associated with in situ high-frequency long-term observations of suspended particulate matter concentration using optical and acoustic sensors
Provedor de dados: 5
Autores: Fettweis, Michael; Riethmüller, Rolf; Verney, Romaric; Becker, Marius; Backers, Joan; Baeye, Matthias; Chapalain, Marion; Claeys, Styn; Claus, Jan; Cox, Tom; Deloffre, Julien; Depreiter, Davy; Druine, Flavie; Flöser, Götz; Grünler, Steffen; Jourdin, Frédéric; Lafite, Robert; Nauw, Janine; Nechad, Bouchra; Röttgers, Rüdiger; Sottolichio, Aldo; Van Engeland, Tom; Vanhaverbeke, Wim; Vereecken, Hans.
Measurement of suspended particulate matter concentration (SPMC) spanning large time and geographical scales have become a matter of growing importance in recent decades. At many places worldwide, complex observation platforms have been installed to capture temporal and spatial variability over scales ranging from cm (turbulent regimes) to whole basins. Long-term in situ measurements of SPMC involve one or more optical and acoustical sensors and, as the ground truth reference, gravimetric measurements of filtered water samples. The estimation of SPMC from optical and acoustical proxies generally results from the combination of a number of independent calibration measurements, as well as regression or inverse models. Direct or indirect measurements of SPMC...
Tipo: Text
Palavras-chave: Suspended particulate matter; Measurement uncertainty; Regression; Optical and acoustical sensors.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00510/62132/66364.pdf

Relation between higher heating value and elemental and mineral biomass plant components
Provedor de dados: 190
Autores: Protásio, Thiago de Paula; Bufalino, Lina; Tonoli, Gustavo Henrique Denzin; Couto, Allan Motta; Trugilho, Paulo Fernando; Guimarães Júnior, Mário.
The aims of this work were to evaluate the correlation, to adjust and select simple and multiple linear statistical models between elemental components (carbon, hydrogen and oxygen) and ash content with higher heating value for plant biomass; to use the principle components analysis for the creation of an energetic development index and to adjust a linear model between energetic development index and higher heating value. Eight types of biomass were used. Three linear and nine multiple statistical models were adjusted. The best models were selected based on the significance of coefficients, adjusted determination coefficient, estimative standard error, coefficient of variation, linearity of parameters, normality, presence of heterocedasticity and lack of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Modeling; Regression; Correlation; Selection Modelagem; Regressão; Correlação; Seleção.
Ano: 2011
URL: http://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/200

Growth curves of meat-producing mammals by von Bertalanffy’s model
Provedor de dados: 86
Autores: Fernandes,Felipe Augusto; Fernandes,Tales Jesus; Pereira,Adriele Aparecida; Meirelles,Sarah Laguna Conceição; Costa,Adriano Carvalho.
Abstract: The objective of this work was to evaluate how the parameterization and the application of different allometric values affect the obtention of the most adequate fit of von Bertalanffy’s model, in the description of the growth curve of meat-producing mammals (bovine, pigs, rabbits, and sheep). Among the nonlinear models, von Bertalanffy’s has been very often applied in several areas, with different parameterizations. This model has been commonly used with an allometric value of m = 2/3; however, for mammals, it is believed that this value can be m = 3/4. The analyzed data referring to the mass of meat-producing mammals according to their age were obtained from research institutions and from the literature. The results showed that von Bertalanffy’s...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Allometry; Modeling; Nonlinear model; Parameterization; Regression.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2019000104307

Lysine and arginine requirements of Salminus brasiliensis
Provedor de dados: 86
Autores: Dairiki,Jony Koji; Borghesi,Ricardo; Dias,Carlos Tadeu dos Santos; Cyrino,José Eurico Possebon.
The objective of this work was to determine the dietary lysine (DL) and dietary arginine (DA) requirements of dourado (Salminus brasiliensis), through dose-response trials using the amino acid profiles of whole carcasses as a reference. Two experiments were carried out in a completely randomized design (n=4). In the first experiment, groups of 12 feed-conditioned dourado juveniles (11.4±0.2 g) were stocked in 60 L cages placed in 300 L plastic indoor tanks in a closed circulation system. Fish were fed for 60 days on diets containing 1.0, 1.5, 2.0, 2.5, 3.0, or 3.5 % dietary lysine. In the second experiment, dourado juveniles (27.0±0.8 g) were fed for 60 days on semipurified diets containing arginine at 1.0, 1.5, 2.0, 2.5 or 3.0%, in similar conditions to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amino acid; Dose-response; Dourado; Regression.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2013000800032

An Appraisal of Beekeeping Activities among Beneficiaries and Non-Beneficiaries of Ekiti State Agricultural Credit Agency (ESACA) Scheme in Nigeria
Provedor de dados: 31
Autores: Fakayode,   S.B.; Babatunde,   Raphael O.; Olowogbon,   S.T.; Adesuyi,   W.S.
The study examined beekeeping activities in Ekiti State, Nigeria. Specifically the study appraised the costs and returns structure of beekeeping activities by beneficiaries of the ESACA scheme, examined the constraints to beekeeping under the scheme and outside the scheme and identified factors that affect beekeeping under the scheme and outside the scheme. A total of 150 beekeeper households were selected; 75 households each for ESACA beneficiary and non-beneficiary respondents across communities popularly known for beekeeping in Ekiti state. Descriptive statistics, costs and returns, regression and Kruscalwallis analyses were employed for data analysis. Beekeeping was found to be more profitable under the ESACA scheme than outside the scheme with returns...
Tipo: Conference Paper or Presentation
Palavras-chave: Kruscal-wallis; Costs and returns structure; Regression; Technical assistance; Crop Production/Industries; Livestock Production/Industries.
Ano: 2010
URL: http://purl.umn.edu/95785

Causal inference with observational data
Provedor de dados: 31
Autores: Nichols,   Austin.
Problems with inferring causal relationships from nonexperimental data are briefly reviewed, and four broad classes of methods designed to allow estimation of and inference about causal parameters are described: panel regression, matching or reweighting, instrumental variables, and regression discontinuity. Practical examples are offered, and discussion focuses on checking required assumptions to the extent possible.
Tipo: Article
Palavras-chave: Xtreg; Psmatch2; Nnmatch; Ivreg; Ivreg2; Ivregress; Rd; Lpoly; Xtoverid; Ranktest; Causal inference; Match; Matching; Reweighting; Propensity score; Panel; Instrumental variables; Excluded instrument; Weak identification; Regression; Discontinuity; Local polynomial; Research Methods/ Statistical Methods.
Ano: 2007
URL: http://purl.umn.edu/119292

Farmer-to-Consumer Direct Marketing: The Role of Customer Satisfaction Measurement for Service Innovations
Provedor de dados: 31
Autores: Spiller,   Achim; Zuhlsdorf,   Anke; Mellin,   Matthias.
The importance of direct marketing for high quality farm products has increased during the past few years. This paper analyses the impact of customer satisfaction and its driving forces for farmer- to-consumer direct marketing and is based on a customer survey in 33 organic and conventional on-farm stores in Germany. The results emphasise the role of store atmosphere and customer service as the main influencing factors on customer satisfaction.
Tipo: Conference Paper or Presentation
Palavras-chave: Direct Marketing; Customer satisfaction; Regression; Service Quality; Agribusiness; Marketing.
Ano: 2007
URL: http://purl.umn.edu/6607

Erratum and discussion of propensity–score reweighting
Provedor de dados: 31
Autores: Nichols,   Austin.
Tipo: Article
Palavras-chave: Xtreg; Psmatch2; Nnmatch; Ivreg; Ivreg2; Ivregress; Rd; Lpoly; Xtoverid; Ranktest; Causal inference; Match; Matching; Reweighting; Propensity score; Panel; Instrumental variables; Excluded instrument; Weak identification; Regression; Discontinuity; Local polynomial; Research Methods/ Statistical Methods.
Ano: 2008
URL: http://purl.umn.edu/122619

Creating print-ready tables in Stata
Provedor de dados: 31
Autores: Lokshin,   Michael; Sajaia,   Zurab.
This article describes the new Stata command xml_tab, which outputs the results of estimation commands and Stata matrices directly into tables in XML format. The XML files can be opened with Microsoft Excel or OpenOffice Calc, or they can be linked with Microsoft Word files. By using XML, xml_tab allows Stata users to apply a rich set of formatting options to the elements of output tables.
Tipo: Article
Palavras-chave: Xml_tab; Estimates; Regression; Matrices; Xml; Excel; Word; Research Methods/ Statistical Methods.
Ano: 2008
URL: http://purl.umn.edu/122600

HEDGE DINÂMICOS: UMA EVIDÊNCIA PARA OS CONTRATOS FUTUROS BRASILEIROS
Provedor de dados: 31
Autores: Bitencourt,   Wanderci Alves; Silva,   Washington Santos; Safadi,   Thelma.
The farming sector is changing, growing and occupying a position of prominence in the economy. These transformations start to demand a bigger concern with the management of risks of the activity. In this direction, the contracts traded at BM&amp;F had become efficient instruments in the reduction of the market risk, through an operation called hedge. However, there is still the necessity of improving of the econometrical techniques for the estimation of the optimal hedge ratio, therefore, it is observed in the brazilian literature that the majority of the works doesn’t consider some aspects of the behavior of the series of returns. Thus, the present work seeks to analyze two methods for the calculation of these hedge optimal ratio, the conventional model...
Tipo: Journal Article
Palavras-chave: Hedge optimal ratio; GARCH BEKK model; Regression.
Ano: 2006
URL: http://purl.umn.edu/43828

SIND BETRIEBSGEMEINSCHAFTEN WIRTSCHAFTLICHER ALS EINZELBETRIEBE?
Provedor de dados: 31
Autores: Lips,   Markus; Pulfer,   Iris; Messer,   Martin.
The influence of farming collectives on income per annual work unit (AWU) is investigated by means of regressions for three types of farms with animal husbandry. The effects are relatively small, and turn out differently for the three farm types. Whereas the effect is negative for the dairy farms (-1200 CHF), collective farming in the case of combined dairying/arable-crop farms and combined pig/poultry farms leads to a higher income (+900 and +500 CHF, respectively). The latter two farm types are characterised by at least two important production branches, unlike the dairy farms, which have just one.  The result for the dairy farms, however, does not call the farming collective into question as a growth opportunity. The usual scale effects that can be...
Tipo: Conference Paper or Presentation
Palavras-chave: Betriebsgemeinschaft; Einzelbetrieb; Einkommen; Regression; Schweiz; Farming collectives; Income; Individual farm; Switzerland; Agribusiness; Farm Management.
Ano: 2007
URL: http://purl.umn.edu/7617

What is Local and for What Foods Does it Matter?
Provedor de dados: 31
Autores: Hu,   Wuyang; Batte,   Marvin T.; Woods,   Timothy A.; Ernst,   Stanley C.
Consumer demand for local foods has been increasing dramatically over the past several years.  Many food producers and marketers are raising their capacity to incorporate local food.  Revenue from local Farmers’ Market and Community Supported Agriculture has become a greater source of income particularly for small and medium-sized farms.  This study answers two important questions related to local food that have not been sufficiently addressed before: what is the greatest distance food can travel and still be accepted by consumers as local and is "local" equally important across food categories.  Using survey data from two states in the USA, this research found that consumers’ accepted food travel distance may be much shorter than what is generally...
Tipo: Conference Paper or Presentation
Palavras-chave: Distance; Food category; Importance rating; Local; Regression; Agribusiness; Agricultural and Food Policy; Consumer/Household Economics; Food Consumption/Nutrition/Food Safety; Marketing; Q13.
Ano: 2010
URL: http://purl.umn.edu/56326

Choosing an appropriate real-life measure of effect size: the case of a continuous predictor and a binary outcome
Provedor de dados: 31
Autores: Conroy,   Ronan M.
A case study of data on age and pregnancy is used to point up some morals for practicing data analysts, including the superiority of regression over t tests, exploratory scatterplot smoothing as a key method of checking form of relationship, and the value of logistic regression followed by adjust as a way of getting at the numbers of most interest.
Tipo: Journal Article
Palavras-chave: Adjust; Correlation; Logistic regression; Regression; Scatterplot smoothing; T tests; Research Methods/ Statistical Methods.
Ano: 2002
URL: http://purl.umn.edu/116011

Dislocation and Regression of the Role of Collective in Land Transfer
Provedor de dados: 31
Autores: Xu,   Wei; Yuan,   Jingheng.
This paper expounds the origin of "collective" in the process of collective land transfer, and analyzes the dislocation phenomenon of the role of collective in the process of collective land transfer as follows: deviation of the role under the conflict of identity; offside of the role under the limitation of democratic construction; omission of the role under the segmentation of interests. In order to protect me legitimate rights of farmers, we should make the role of collective to revert on the basis of township government, farmer and collective, so that the role of collective is restored under the management of government; the role of collective reverts under the supervision of farmers; the role of collective returns under its own strengthening of...
Tipo: Journal Article
Palavras-chave: Land transfer; Role of collective; Dislocation; Regression; China; Agribusiness.
Ano: 2011
URL: http://purl.umn.edu/118289

Speaking Stata: Graphing model diagnostics
Provedor de dados: 31
Autores: Cox,   Nicholas J.
Plotting diagnostic information calculated from residuals and fitted values is a long-standard method for assessing models and seeking ways of improving them. This column focuses on the statistical mainstream defined by regression models for continuous responses, treated in a broad sense to include (for example) generalized linear models. After some comments on the history of such ideas (and even their anthropology and psychology), the commands available in official Stata are reviewed, and a modeldiag package is introduced. A detailed example on fuelwood yield from fallow areas in Nigeria illustrates a variety of general points and specific tips.
Tipo: Journal Article
Palavras-chave: Modeldiag; Anovaplot; Indexplot; Ofrtplot; Ovfplot; Qfrplot; Racplot; Rdplot; Regplot; Rhetplot; Rvfplot2; Rvlrplot; Rvpplot2; Graphics; Diagnostics; Regression; Generalized linear models; Analysis of variance; Research Methods/ Statistical Methods.
Ano: 2004
URL: http://purl.umn.edu/116273

Biomass and grain yield of oats by growth regulator
Provedor de dados: 91
Autores: Marolli,Anderson; Silva,José A. G. da; Romitti,Marcos V.; Mantai,Rubia D.; Hawerroth,Maraisa C.; Scremin,Osmar B.
ABSTRACT The use of growth regulator in oats can reduce plant lodging with reflections in biomass and grain yield. The objective of the study was to determine the feasibility and efficiency of using Trinexapac-Ethyl regulator in the growth of white oat under different conditions of N-fertilizer and years favorable and unfavorable for cultivation. In this study, two experiments were conducted in the years 2011, 2012 and 2013, one for quantifying biomass production rate and the other for the determination of grain yield and lodging. The experimental design was randomized blocks with four replicates, in a 4 x 3 factorial scheme, for growth regulator doses (0, 200, 400 and 600 mL ha-1) and nitrogen doses (30, 90 and 150 kg ha-1), respectively. There is a...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Avena sativa; Trinexapac-ethyl; Lodging; Nitrogen; Regression.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000300163

Common factors method to predict the carcass composition tissue in kid goats
Provedor de dados: 96
Autores: Gomes,Helen Fernanda Barros; Gonçalves,Heraldo Cesar; Polizel Neto,Angelo; Cañizares,Gil Ignacio Lara; Roça,Roberto de Oliveira; Marques,Raquel Ornelas; Oliveira,Giuliana Micai de; Queiroz,Edicarlos Oliveira.
The objective of this work was to analyze the interrelations among weights and carcass measures of the longissimus lumborum muscle thickness and area, and of sternum tissue thickness, measured directly on carcass and by ultrasound scan. Measures were taken on live animals and after slaughter to develop models of multiple linear regression, to estimate the composition of shoulder blade, from selected variables in 89 kids of both genders and five breed groups, raised in feedlot system. The variables considered relevant and not redundant on the information they carry, for the common factor analysis, were used in the carcass composition estimate development models. The presuppositions of linear regression models relative to residues were evaluated, the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Co-linearity; Correlation; Evaluation; Goat; Regression.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982013000300007

Characterization and influence of production factors on growing and finishing pig farms in Brazilian cooperatives
Provedor de dados: 96
Autores: Silva,Caio Abércio da; Agostini,Piero da Silva; Dias,Cleandro Pazinato; Callegari,Marco Aurélio; Santos,Rita de Kássia Silva dos; Novais,Aliny Kétilim; Pierozan,Carlos Rodolfo; Gasó,Josep Gasa.
ABSTRACT The objective of this study was to identify and quantify, through mathematical models, the main factors of production in growing and finishing pig units linked to three Brazilian cooperatives located in Western Region of Paraná State that influence the parameters of daily feed intake and feed conversion ratio. The records of 216 growing and finishing farms from 2010 to 2013, representing 1,533 batches, and totaling approximately 1,025,000 pigs, were evaluated. Thirty production factors related to the management, health, installations and equipment, nutrition, genetics, and environment were considered. The number of pigs per pen, the feeder model, the origin and sex of the animals, and the initial and final body weights were the factors included in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Facilities; Fattening; Intake; Production indexes; Regression.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982017000300264

Study on the growth curve of the internal cavity of ‘Dwarf green’ coconut fruits
Provedor de dados: 124
Autores: Prado,Thalita Kelen Leal do; Savian,Taciana Villela; Fernandes,Tales Jesus; Muniz,Joel Augusto.
ABSTRACT The aim of the work was to evaluate the adjustment of the logistic and gompertz model with structure of first-order autoregressive errors in the study on the ‘Dwarf green’ coconut fruit growth based on longitudinal and cross-sectional internal cavity diameter data (DLCI and DTCI). Model adjustments showed positive residual autocorrelation, according to the Durbin-Watson test and for both variables, DLCI and DTCI, the residue was modeled according to first-order autoregressive process (AR1). The analysis was performed using the least squares method in the PROC MODEL of the SAS software and results indicated that for both characteristics under study, the logistic model was the most appropriate in describing fruit growth and, according to the model,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Regression; Least squares; Autoregressive errors; Non-linear.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902020000300401

Crop area estimate from original and simulated spatial resolution data and landscape metrics
Provedor de dados: 63
Autores: Soares,Dênis de Moura; Galvão,Lênio Soares; Formaggio,Antônio Roberto.
Images acquired at the same day by the ETM+/Landsat-7 (30 m of spatial resolution) and MODIS/Terra (250 m) sensors were used to estimate areas of three major crops (soybean, sugarcane, and corn) with different landscape patterns in Southeastern Brazil. Majority filtering of ETM + classification results was applied to describe the behavior of 15 selected landscape metrics at distinct simulated spatial resolutions (90, 150, 210 and 270 m). By using regression models, the performance of MODIS and derived metrics to predict adequately the crop area, considering ETM+ data as reference, were analyzed. Results showed that the MODIS instrument overestimated the areas of soybean (15%) and sugarcane (1%), and underestimated the area of corn (12%). Multiple...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: MODIS; Remote sensing; Regression; Soybean; Sugarcane.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162008000500003

Physiological model to estimate the maturity of sugarcane
Provedor de dados: 63
Autores: Scarpari,Maximiliano Salles; Beauclair,Edgar Gomes Ferreira de.
Sugarcane (Saccharum spp.) grows in different weather and management conditions which directly affect crop maturation. These conditions lead to the necessity of quantifying crop response to different stimuli for planning purposes. Forecast models for the quality of raw material are important tools in sugarcane farming, especially the forecast curve of sucrose accumulation in shoots. The goal of these models is to supply yield estimates during the crop cycle, aiming to characterize alternatives and to increase the efficacy for management and strategic decisions. The objective of this project was to develop empiric models capable of obtaining estimates of total recoverable sugar (TRS), for the varieties RB72454, SP81-3250 and SP80-1842 during the crop cycle,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Climatology; Crop models; Productivity; Regression; Sucrose.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162009000500006

Estimation of leaf area for greenhouse cucumber by linear measurements under salinity and grafting
Provedor de dados: 63
Autores: Blanco,Flávio Favaro; Folegatti,Marcos Vinícius.
The measurement of leaf area by linear parameters is a useful tool when plants cannot be destroyed for direct measurement. The objectives of this study were to establish equations to estimate the leaf area of greenhouse-cucumber and to evaluate the effects of salinity and grafting on this estimative. Non-grafted cucumber seedlings, cv. 'Hokushin', were transplanted in a greenhouse and were irrigated with water of different salinities (1.0, 3.2 and 5.0 dS m-1). In the second growing period, the same cultivar was grafted on Cucurbita spp. and the plants were irrigated with water of 1.4, 3.0 and 5.3 dS m-1. Leaves of different sizes were collected from both experiments and leaf area was determined by an integrating area meter. Leaf length (L) and width (W)...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Regression; Irrigation water salinity.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162005000400001

Specific draft modeling for combined and simple tillage implements using mathematical, regression and ANN modeling in silty clay loam soil
Provedor de dados: 111
Autores: zaki, hassan; khorasani, Mohammad Esmail; aghili nategh, nahid; Sheikhdavoodi, Mohammad; andekaiezadeh, Korosh.
Specific draft is one of the important parameters in the design of tillage tools and estimation of energy consumption in tillage operations, which makes it useful. For this reason, it’s prediction and modeling about different working conditions (depth of plowing and advance velocity) provide the possibility to determine the proper working conditions of tillage implements. In this study, two groups of tillage implements with different geometry including combined tillage implements (combined tiller and chisel packer) and simple tillage implements (moldboard plow, disk plow, chisel plow and offset disk harrow) are used. Also 3 speeds (3, 4.5 and 6 km / h) and 3 different depths (15, 20 and 25 cm) in silty clay loamy soil (47% silt, 22% sand and 31% clay) with...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Specific Draft; Tillage tools; Regression; ANN; Depth; Forward speed.
Ano: 2022
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/6433

Development of empirical regression equations for predicting the performances of disc plough and harrow in clay-loam soil
Provedor de dados: 111
Autores: Oduma, Okechukwu.
Abstract: The regression equations for predicting the performances of plough and harrow implements in clay – loam soil in South – East agro – ecological region of Nigeria were developed. This is to enable farmers, farm managers and users of farm machinery assess and select proper machinery based on soil type/ condition for good performance of the machine and to avoid unnecessary breakdown/failures or energy loss during operation and generally to optimize production at minimum cost. Results showed that for plough operated in clay – loam soil, the regression equation that can predict its various performance indicators are: field efficiency, Y = 0.067x2 – 0.7733x + 89.283; effective field capacity, Y = 0.0864x2 – 1.4406x +6.8173; theoretical field capacity, Y...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: AGRICULTURAL AND BIORESOURCES ENGINEERING Keywords: empirical; Harrow; Plough; Performances; Regression; Soil type.
Ano: 2019
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/5390

Recovering missing data: estimating position and size of caudal vertebrae in Staurikosaurus pricei Colbert, 1970
Provedor de dados: 42
Autores: Grillo,Orlando N.; Azevedo,Sergio A.K.
Missing data is a common problem in paleontology. It makes it difficult to reconstruct extinct taxa accurately and restrains the inclusion of some taxa on comparative and biomechanical studies. Particularly, estimating the position of vertebrae on incomplete series is often non-empirical and does not allow precise estimation of missing parts. In this work we present a method for calculating the position of preserved middle sequences of caudal vertebrae in the saurischian dinosaur Staurikosaurus pricei, based on the length and height of preserved anterior and posterior caudal vertebral centra. Regression equations were used to estimate these dimensions for middle vertebrae and, consequently, to assess the position of the preserved middle sequences. It also...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Missing data; Caudal vertebra; Regression; Staurikosaurus pricei.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652011000100004

Robust volumetric models for supporting the management of secondary forest stands in the Southern Brazilian Atlantic Forest
Provedor de dados: 42
Autores: OLIVEIRA,LAIO Z.; KLITZKE,ALINE R.; FANTINI,ALFREDO C.; ULLER,HEITOR F.; CORREIA,JEAN; VIBRANS,ALEXANDER C.
Abstract The majority of Atlantic Forest fragments in Southern Brazil are second-growth forests dominated by fast-growing species with considerable market-value timber. Nevertheless, volume prediction models are scarce, especially to estimate tree total volume (i.e., stem plus branches). This study approached the issue through the following aims: to fit and select stem and total volume models (generic and species-specific) using data from 288 harvested trees in a management operation, and to fit generic and species-specific bark factors. The power model embedding diameter at breast height (D) and tree stem or total height (H) presented the greatest prediction strength for both stem and total tree volume. Models including only D to predict total tree volume...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Forest inventory; Mata Atlântica; Modelling; Regression.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652018000703729

Statistical methods to study adaptability and stability in breeding lines of food-type soybeans
Provedor de dados: 53
Autores: Freiria,Gustavo Henrique; Gonçalves,Leandro Simões Azeredo; Furlan,Felipe Favoretto; Fonseca Junior,Nelson da Silva; Lima,Wilmar Ferreira; Prete,Cássio Egidio Cavenaghi.
ABSTRACT The grains of food-type soybean cultivars, which are characterized by the absence of lipoxygenases and the presence of high levels of proteins and isoflavones, are regarded as functional foods with high acceptance by consumers. However, few cultivars of food-type soybeans are currently available in the Brazilian market. The aim of this work was to study the adaptability and stability of various genotypes of food-type soybeans and to compare the performance of methods, which are based on analysis of variance, non-parametric, regression, multivariate and mixed models. Ten lines of food-type soybeans obtained from the Breeding Program of Soybeans for Human Consumption of the State University of Londrina (UEL/BPSHC) and two commercial varieties, the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glycine max; Yield; Non-parametric; Regression; Multivariate; Mixed models.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052018000200253

Propranolol inhibits the proliferation, migration and tube formation of hemangioma cells through HIF-1α dependent mechanisms
Provedor de dados: 56
Autores: Chen,Y.Z.; Bai,N.; Bi,J.H.; Liu,X.W.; Xu,G.Q.; Zhang,L.F.; Li,X.Q.; Huo,R.
The aim of this study was to investigate the mechanism of propranolol on the regression of hemangiomas. Propranolol-treated hemangioma tissues were collected and the expression of hypoxia inducible factor-1α (HIF-1α) was examined. We also established HIF-1α overexpression and knockdown hemangioma cells, and determined the effects of HIF-1α on the hemangioma cells proliferation, apoptosis, migration and tube formation. Significantly increased HIF-1α level was found in the hemangioma tissues compared to that in normal vascular tissues, whereas propranolol treatment decreased the HIF-1α level in hemangioma tissues in a time- and dose-dependent manner. Moreover, propranolol treatment significantly decreased cell proliferation, migration and tube formation as...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Propranolol; Hemangiomas; Hypoxia inducible factor-1α; Knockdown; Regression.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2017001200601

Endogenous losses and true digestibility of phosphorus in rice bran with or without phytase determined with piglets
Provedor de dados: 65
Autores: Lucca,Walter; Alves,Débora Aline; Rocha,Leonardo Tombesi da; Shirmann,Graciele Dalise; Camargo,Claudiele Aparecida do Santos; Figueiredo,Andriele Medianeira; Zanella,Irineo; Oliveira,Vladimir de.
ABSTRACT: The aim of this study was to determine endogenous losses and true total digestibility of phosphorus (P) in piglets fed with diets containing rice bran (RB), and supplemented or not with phytase. The experiment was divided into three periods of 12 days each, seven for adaptation and five for total feces collection, with an interval of three days between periods. Twelve barrows with average body weights of 13.40±1.00kg at 46 days of age were distributed among six treatments consisting of diets formulated with three levels of RB (5%, 10%, and 20%) with or without the addition of 750FTUkg-1 of phytase. The amount of total daily feed was divided into four daily meals and water was available ad libitum. The method of total feces collection was used...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Endogenous losses; Phytase; Regression; Total collection.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782016000601082

Quantitative trait loci associated with resistance to gray leaf spot and grain yield in corn
Provedor de dados: 64
Autores: Veiga,Adriano Delly; Pinho,Renzo Garcia Von; Resende,Luciane Vilela; Pinho,Édila Vilela de Resende Von; Balestre,Márcio; Pereira,Laís Andrade.
The main objectives of hybrid development programs include incorporating genetic resistance to diseases and increasing grain yield. Identification of Quantitative Trait Loci (QTL) through the statistical analysis of molecular markers allows efficient selection of resistant and productive hybrids. The objective of this research was to identify QTL associated with resistance to gray leaf spot and for grain yield in the germplasm of tropical corn. We used two strains with different degrees of reaction to the disease; the genotypes are owned by GENESEEDS Ltda, their F1 hybrid and the F2 population. The plants were evaluated for gray leaf spot resistance, for grain yield and were genotyped with 94 microsatellite markers. Association of the markers with the QTL...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Maximum likelihood; Microsatellites; Regression.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542012000100004

Sisvar: a computer statistical analysis system
Provedor de dados: 64
Autores: Ferreira,Daniel Furtado.
Sisvar is a statistical analysis system, first released in 1996 although its development began in 1994. The first version was done in the programming language Pascal and compiled with Borland Turbo Pascal 3. Sisvar was developed to achieve some specific goals. The first objective was to obtain software that could be used directly on the statistical experimental course of the Department of Exact Science at the Federal University of Lavras. The second objective was to initiate the development of a genuinely Brazilian free software program that met the demands and peculiarities of research conducted in the country. The third goal was to present statistical analysis software for the Brazilian scientific community that would allow research results to be...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Multiple comparisons; Analysis of variance; Regression; Hypothesis tests.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542011000600001