SABIIA - Sistema Aberto e Integrado de Informação em Agricultura (Sabiia)

Koch, Alexander K.; Lazarov, Zdravetz.

More liquid financial contracts are claimed to draw trading volume from contracts for which they are close substitutes. We provide the first analysis of how trading volume across existing financial contracts is affected by changes in the factors that govern the degree to which they are substitutes. Using data on DAX options with different strike prices, we identify these factors and their impact on the distribution of trades across contracts. The results are relevant for exchange design since they help gauge when options with different strike prices are good (bad) substitutes and the strike price grid should be coarse (fine).

Tipo: Journal Article

Palavras-chave: Clustering; Exchange Design; Options; Risk and Uncertainty; G10; G20; L15.

Ano: 2007

URL: http://purl.umn.edu/50155

Modeling Site Specific Heterogeneity in an On-Site Stratified Random Sample of Recreational Demand

Sardana, Kavita; Bergstrom, John C..

Using estimation of demand for the George Washington/Jefferson National Forest as a case study, it is shown that in a stratified/clustered on-site sample, latent heterogeneity needs to be accounted for twice: first to account for dispersion in the data caused by unobservability of the process that results in low and high frequency visitors in the population, and second to capture unobservable heterogeneity among individuals surveyed at different sites according to a stratified random sample (site specific effects). It is shown that both of the parameters capturing latent heterogeneity are statistically significant. It is therefore claimed in this paper, that the model accounting for site-specific effects is superior to the model without such effects....

Forecasting Housing Prices under Different Submarket Assumptions

Palavras-chave: Recreational Demand models; Clustering; Subject-specific effects; Truncated Stratified Negative Binomial Model; Overdispersion; Environmental Economics and Policy.

Ano: 2011

URL: http://purl.umn.edu/103868

Chen, Zhuo; Cho, Seong-Hoon; Poudyal, Neelam C.; Roberts, Roland K..

This research evaluated forecasting accuracy of hedonic price models based on a number of different submarket assumptions. Using home sale data for the City of Knoxville and vicinities merged with geographic information, we found that forecasting housing prices with submarkets defined using expert knowledge and by school district and combining information conveyed in different modeling strategies are more accurate and efficient than models that are spatially aggregated, or with submarkets defined by statistical clustering techniques. This finding provided useful implications for housing price prediction in an urban setting and surrounding areas in that forecasting models based on expert knowledge of market structure or public school quality and simple...

DIETARY EVOLUTION OVER TIME IN EUROPE, BETWEEN CYCLOPS AND PHAECIANS . AN OUTLOOK ON THE ROLE OF SUPPLY-SIDE FACTORS IN DRIVING CHANGES IN THE FOOD PATTERNS

Palavras-chave: Clustering; Forecasting; Hedonic price; Housing Submarket; Demand and Price Analysis; C53; R21.

Ano: 2007

URL: http://purl.umn.edu/9689

Finardi, Corrado; Arfini, Filippo; Turrini, Aida.

The present study intends to shed light, both from a descriptive and investigative point of view on the dietary evolution taking place in Europe during last 45 years, using secondary data from FAO FBS, which can cover the entire time span considered and allow for several extrapolation and timeseries analysis, differently than single survey data.. After a clustering of selected european national diets, using specific metrics with respect both to internal and external variety (as measured by appropriate indicators), we intended to check the actual distance that average, national diets have in front of the so called Food Pyramid, which consists in a balance of several food items in adequate proportions and in fact glorifies the healthy virtues of the...

The Value of Good Neighbors: A Spatial Analysis of the California and Washington Wine Industries

Palavras-chave: Diets; Evolution; Clustering; Food pyramid; Europe; Trade; GI; Agricultural and Food Policy; Consumer/Household Economics; Demand and Price Analysis; Food Consumption/Nutrition/Food Safety; Food Security and Poverty; Health Economics and Policy; E37; Q18.

Ano: 2010

URL: http://purl.umn.edu/116443

Yang, Nan; McCluskey, Jill J.; Brady, Michael P..

The fact that wineries tend to cluster in certain sub-regions can be partially explained by the terroir of those areas. However, a gap in our understanding of the spatial relationships among wineries remains. In this article, winery-level data with geographic information system (GIS) coordinates are utilized to examine the spatial relationships among neighboring wineries. Spatial effects for the California and Washington wine industries are assessed by performing clustering tests based on wine prices and tasting scores. A spatial lag model is then estimated to test the hypothesis that there are positive effects from neighbors when analyzing the hedonic price equations. The regression results indicate that there exists strong and positive neighbor...

Production technology and quality of corn silage for feeding dairy cattle in Southern Brazil

Palavras-chave: GIS; Clustering; Spatial lag model; Wine; Agricultural and Food Policy.

Ano: 2010

URL: http://purl.umn.edu/61172

R. Bras. Zootec.

Silva,Mábio Silvan José da; Jobim,Clóves Cabreira; Poppi,Edson Carlos; Tres,Tamara Tais; Osmari,Milene Puntel.

ABSTRACTThe objective of this study was to evaluate the production practices and use of corn silage in dairy farms in Southern Brazil, and to evaluate their impact on the nutritional quality and occurrence of mycotoxins. The data were collected by application of questionnaires among the producers, and by analysis of silage samples. The variables were subjected to factorial analysis of data reduction through the principal components method, thus obtaining 84.12% of the variance associated with the location, corn hybrid, crop production management, and inoculant used, characterizing the farms into four distinct groups. In farms from Paraná, the silage production technologies were more associated with implantation and crop management processes, and investment...

Genetic divergence of Anthurium affine germplasm using morphoagronomic and molecular descriptors

Palavras-chave: Clustering; Inoculant; Maize; Mycotoxins; Silage production.

Ano: 2015

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982015000900303

Rev. Ciênc. Agron.

Maia,Clara Yohana; Soares,Nazaré Suziane; Castro,Ana Cecília Ribeiro; Queirós,João Ravelly Alves de; Aragão,Fernando Antonio Souza de; Bordallo,Patricia do Nascimento.

ABSTRACT Anthurium affine is an ornamental Brazilian native plant very appreciated due to its long-lasting durability. To explore the genetic diversity available, 21 A. affine half-sibling progeny were evaluated using morphoagronomic and molecular descriptors. The morphoagronomic descriptors used were: plant height, plant diameter, growth habit, leaf number, leaf blade length, leaf blade width, petiole length, petiole diameter, leaf margin undulation, general appearance; soil cover rate and Random Amplified Polymorphic DNA (RAPD) markers the molecular one. All the descriptors within the progeny showed variability and general appearance, leaf margin undulation and soil cover rate are the ones that most contribute to the plants divergence. From 45 RAPD...

APPLE IDENTIFICATION IN FIELD ENVIRONMENT WITH OVER THE ROW MACHINE VISION SYSTEM

Palavras-chave: Clustering; Characterization; Genetic variation; Ornamental; RAPD.

Ano: 2020

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902020000400410

CIGR Journal

Silwal, Abhisesh; Gongal, Aleana; Karkee, Manoj.

Accurate detection and identification of fruits is critically important for the success of developing automated apple harvesting system. Research has been conducted to identify apples in orchard environment with reasonable accuracy when apples are clearly visible or partially occluded. However, only limited work has been carried out to identify fruit in clusters, which is critically important as fruit clusters are common in field conditions. This work focused on accurately identifying partially visible apples and apples in clusters using a machine vision system. An over the row platform with tunnel structure and artificial lighting was used to increase uniformity in imaging environment. Iterative Circular Hough Transform (CHT) was used to detect clearly...

Glycosynapses: microdomains controlling carbohydrate-dependent cell adhesion and signaling

Palavras-chave: Agricultural Engineering; Mechanization and Automation apple identification; Clustering; Circular Hough Transform; Blob analysis.

Ano: 2014

URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3006

Anais da ABC (AABC)

Hakomori,Senitiroh.

The concept of microdomains in plasma membranes was developed over two decades, following observation of polarity of membrane based on clustering of specific membrane components. Microdomains involved in carbohydrate-dependent cell adhesion with concurrent signal transduction that affect cellular phenotype are termed "glycosynapse". Three types of glycosynapse have been distinguished: "type 1" having glycosphingolipid associated with signal transducers (small G-proteins, cSrc, Src family kinases) and proteolipids; "type 2" having O-linked mucin-type glycoprotein associated with Src family kinases; and "type 3" having N-linked integrin receptor complexed with tetraspanin and ganglioside. Different cell types are characterized by presence of specific types...

Genetic divergence among cupuaçu accessions by multiscale bootstrap resampling

Palavras-chave: Clustering; Carbohydrate-to-carbohydrate interaction; Carbohydrate-binding protein; Integrin; Tetraspanin; Growth factor receptor.

Ano: 2004

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652004000300010

Bragantia

Santos,Vinicius Silva dos; Martins Filho,Sebastião; Alves,Rafael Moysés; Resende,Marcos Deon Vilela de; Silva,Fabyano Fonseca e.

This study aimed at investigating the genetic divergence of eighteen accessions of cupuaçu trees based on fruit morphometric traits and comparing usual methods of cluster analysis with the proposed multiscale bootstrap resampling methodology. The data were obtained from an experiment conducted in Tomé-Açu city (PA, Brazil), arranged in a completely randomized design with eighteen cupuaçu accessions and 10 repetitions, from 2004 to 2011. Genetic parameters were estimated by restricted maximum likelihood/best linear unbiased prediction (REML/BLUP) methodology. The predicted breeding values were used in the study on genetic divergence through Unweighted Pair Cluster Method with Arithmetic Mean (UPGMA) hierarchical clustering and Tocher’s optimization method...

Energy Efficient Clustering in Multi-hop Wireless Sensor Networks Using Differential Evolutionary MOPSO

Palavras-chave: Clustering; UPGMA; Tocher; Theobroma grandiflorum.

Ano: 2015

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052015000200169

BABT

Prasad,D. Rajendra; Naganjaneyulu,P. V.; Prasad,K. Satya.

ABSTRACT The primary challenge in organizing sensor networks is energy efficacy. This requisite for energy efficacy is because sensor nodes capacities are limited and replacing them is not viable. This restriction further decreases network lifetime. Node lifetime varies depending on the requisites expected of its battery. Hence, primary element in constructing sensor networks is resilience to deal with decreasing lifetime of all sensor nodes. Various network infrastructures as well as their routing protocols for reduction of power utilization as well as to prolong network lifetime are studied. After analysis, it is observed that network constructions that depend on clustering are the most effective methods in terms of power utilization. Clustering divides...

Clustering of Enterococcus faecalis infections in a cardiology hospital neonatal intensive care unit

Palavras-chave: Wireless Sensor Network (WSN); Clustering; Low Energy Adaptive Clustering Protocol (LEACH); Particle Swarm Optimization (PSO); Multi-Objective Particle Swarm Optimization (MOPSO); Differential Evolution (DE).

Ano: 2016

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132016000300600

BJID

Strabelli,Tânia Mara Varejão; Cais,Daiane P.; Zeigler,Rogério; Siciliano,Rinaldo; Rodrigues,Cristhieni; Carrara,Dirceu; Neres,Suzi; Lessa,Sarita; Uip,David Everson.

Early identification of an outbreak is one of the main advantages of routine epidemiological surveillance. Enterococcus spp. used to be regarded as microorganisms of low pathogenicity, because they are part of the normal microbial flora of the gastrointestinal and genitourinary tract. Recently, they have emerged as important pathogenic agents, sometimes causing infections with high mortality rates. We studied a clustering of primary bloodstream infections caused by Enterococcus faecalis in a cardiology hospital neonatal intensive care unit (NICU). Four cases of primary bloodstream infection by E. faecalis were detected from April 15 to May 13, 2004, during active infection surveillance. The isolates were sensitive to glycopeptides. Some aspects of the...

Genetic variability of selected Passiflora alata genotypes based on the physical characteristics of fruits

Palavras-chave: Enterococcus faecalis; Clustering; Neonatal intensive care unit; Bloodstream; Infection.

Ano: 2006

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702006000200008

Ciência Rural

D'Abadia,Ana Claudia Alves; Faleiro,Fábio Gelape; Costa,Ana Maria; Junqueira,Nilton Tadeu Vilela; Braga,Marcelo Fideles.

ABSTRACT: Over several past centuries, specific plant populations have been carefully selected to filter strains with higher agronomic performance. Genetic variability is most essential for successful selection. The Passiflora genus offers great inter- and intra-specific variability. This study aimed to evaluate the physical characteristics of the genotypes of the elite passion fruit (Passiflora alata) for selection purpose. We considered the physical traits of fruit mass, longitudinal and equatorial diameters, peel thickness and color, and pulp mass and volume without and with seeds and pulp yield. The sources of variation for the analysis of variance included the fruits of 8 elite genotypes, with 3 replications, whose means were compared by Tukey’s test...