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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Análise dos acidentes de trânsito do Município de São Carlos utilizando o Sistema de Informação Geográfica - SIG e ferramentas de estatística espacial.

Santos, Luciano dos 20 February 2006 (has links)
Made available in DSpace on 2016-06-02T20:00:16Z (GMT). No. of bitstreams: 1 DissLS.pdf: 7958498 bytes, checksum: 72fd51dc4f0a7e88e90a7ab3929a73b1 (MD5) Previous issue date: 2006-02-20 / Financiadora de Estudos e Projetos / The traffic accidents have reached high records, registering a great amount of wounded and material damages. One of the largest concerns of the responsible organs for the planning of the traffic and transport is to find solutions that can come to reduce the numbers of traffic accidents. In this context, this work had as main objective to accomplish a spatial analysis of the accidents of traffic on the municipal district of São Carlos - SP, using a of Geographic Information System (GIS) associated to tools of Spatial Statistics, with the intention of identifying the points and areas of larger occurrence of accidents, as well as the spatial tendencies of growth. The work has been developed in two stages: a) determination of punctual patterns; and b) determination of critical zones. For the accomplishment of this work was necessary to make a geographic reference of the traffic accidents, happened between 2001 and 2003. The Spatial Statistics tools used in this work were the Index of Moran, Average Space Piece of furniture, among others; they were used for the accomplishment of groupings of traffic accidents, determination of the critical zones of accidents and the tendencies of displacement of the accidents. The work showed that the traffic accidents happen in all the mesh of urban way, with a larger incidence of accidents with material damages in the central areas of the city and accidents with victims in the outlying areas. It was possible to observe that a displacement of the accidents of traffic exists for almost all the areas of the São Carlos city, it being a spatial phenomenon of difficult treatment. The largest difficulty founded for the accomplishment of this work were linked to the analysis of the consistence of the information, it mean that the analyses of the traffic accidents will be each time more satisfactory, if we pay a larger attention in the collection process and storage of those information. / Os acidentes de trânsito têm assumido números elevados, registrando uma grande quantidade de feridos e danos materiais. Uma das maiores preocupações dos órgãos responsáveis pelo planejamento do trânsito e transporte é encontrar soluções que possam vir a reduzir os números de acidentes de trânsito. Neste contexto, esse trabalho teve como principal objetivo o de realizar uma análise espacial dos acidentes de trânsito do município de São Carlos - SP, fazendo-se uso de Sistemas de Informações Geográficas SIG, associados a ferramentas de Estatística Espacial, com a intenção de identificar os pontos e áreas de maior ocorrência de acidentes, bem como as tendências espaciais de crescimento. O trabalho divide-se em duas etapas: a)identificação de padrões pontuais; e b)identificação de zonas críticas. Para a realização deste trabalho foi necessário efetuar o georreferenciamento dos acidentes de trânsito, ocorridos entre 2001 e 2003. As ferramentas de Estatística Espacial utilizadas, tais como Índice de Moran, Média Espacial Móvel, dentre outras, serviram para a realização de agrupamentos de acidentes de trânsito, identificação das zonas críticas de acidentes e identificação de tendências de deslocamento dos acidentes. A pesquisa mostrou que os acidentes de trânsito ocorrem por toda malha viária, de maneira geral, com uma maior incidência de acidentes com danos materiais nas áreas centrais da cidade e acidentes com vítimas mais nas regiões periféricas. Foi possível observar que existe um deslocamento dos acidentes de trânsito para quase todas as regiões da cidade de São Carlos, tornando um fenômeno espacial de difícil tratamento. As maiores dificuldades encontradas para a realização deste trabalho estão ligadas à análise da consistência das informações. Concluiu-se que, para que as análises dos acidentes de trânsito obtenham resultados cada vez mais satisfatórios, é necessária uma maior atenção no processo de coleta e armazenamento dessas informações, tornando-as cada vez melhores.
62

Avaliação da suscetibilidade à erosão da bacia hidrográfica do Alto Camaquã - RS

Cunha, Henrique Noguez da January 2016 (has links)
A exploração excessiva dos recursos naturais e o uso desordenado do espaço buscando uma rentabilidade máxima dos sistemas, originou uma intensa preocupação com as implicações ambientais resultantes da falta de gestão do espaço natural. Para o estudo dos processos de degradação ambiental é necessário analisar os elementos do meio físico e antrópico que participam desse processo, onde a espacialização das informações requer a utilização de sistemas e modelos nos quais seja possível integrar os dados. Nesse sentido, o objetivo do presente trabalho foi avaliar e espacializar os graus de suscetibilidade à erosão na Bacia Hidrográfica do Alto Camaquã com base em geotecnologias, em especial o sensoriamento remoto e o Sistema de Informações Geográficas. Foram avaliados os aspectos físicos e antrópicos da bacia hidrográfica de acordo com o grau de suscetibilidade à erosão. Os resultados da suscetibilidade à erosão da Bacia Hidrográfica do Alto Camaquã tenderam à “estabilidade/ suscetibilidade mediana” com 3.111,5 km² (60,7%) e menor representação das classes “Estável” com 138,4 km² (2,7%), Moderadamente Estável” com 1358,4 km² (26,5%), “Moderadamente Suscetível” com 389,5 km² (7,6%) e “Suscetível” com 128,2 km² (2,5%), contudo, a avaliação dos parâmetros físicos e antrópicos analisados separadamente resultaram em duas regiões distintas. (1) Na região oeste os aspectos físicos tendem à estabilidade e os aspectos antrópicos à suscetibilidade, caracterizados pela mecanização agrícola sobre relevo plano à suave ondulado. (2) Na região leste, o meio físico tende à suscetibilidade e o uso da terra à estabilidade, cujo relevo apresenta, em grande parte, alta declividade e presença de morros com afloramento rochoso, condições inaptas às atividades agrícolas intensivas. / The excessive exploration of natural resources and the uncontrolled use of the territory, seeking a maximum profitability of the systems, has caused an intense concern about the environmental implications arising from lack of management of the natural areas. The environmental degradation processes are analyzed by the physical environment elements and the land covers and land uses included in the process, when data are integrated by geographical information systems and spatial models. In this sense, the objective of this study was to evaluate the susceptibility to erosion in the watershed of the Upper Camaquã river based on geotechnology, with emphasis in remote sensing and Geographic Information Systems. We evaluated the physical and anthropic aspects of the watershed according to the degree of susceptibility to erosion The Upper Camaquã watershed showed "stability/median susceptibility" with 3.111,5 square kilometers (60,7%) and lower representation of classes "Stable" with 138.4 km² ( 2.7%) “Moderately Stable " with 1358.4 square kilometers (26.5%) , " Moderately Susceptible" with 389.5 km² (7.6%) and "Susceptible" with 128.2 square kilometers (2.5%), however, two regions occurred when the physical and anthropogenic components were considered separately: (1) The western region with stable physical aspects, susceptible anthropogenic aspects and agricultural mechanization on flat to gently rolling terrains; (2) the eastern region with susceptible physical environment, stable land use, where terrain has largely, steep slopes and hilly terrains with rocky outcrop, unfit conditions to intensive agricultural activities.
63

Predictive Habitat Models for Four Cetaceans in the Mid-Atlantic Bight

Cross, Cheryl L. 27 May 2010 (has links)
This study focuses on the habitats of cetaceans in the Mid-Atlantic Bight, a region characterized by bathymetric diversity and the presence of distinct water masses (i.e. the shelf water, slope water, and Gulf Stream). The combination of these features contributes to the hydrographic complexity of the area, which furthermore influences biological productivity and potential prey available for cetaceans. The collection of cetacean sighting data together with physical oceanographic data can be used to examine cetacean habitat associations. Cetacean habitat modeling is a mechanism for predicting cetacean distribution patterns based on environmental variables such as bathymetric and physical properties, and for exploring the potential ecological implications that contribute to cetacean spatial distributions. We can advance conservation efforts of cetacean populations by expanding our knowledge of their habitats and distribution. Generalized additive models (GAMs) were developed to predict the spatial distribution patterns of sperm whales (Physeter macrocephalus), pilot whales (Globicephala spp.), bottlenose dolphins (Tursiops truncatus), and Atlantic spotted dolphins (Stenella frontalis) based on significant physical parameters along the continental shelf-break region in the Mid-Atlantic Bight. Data implemented in the GAMs were collected in the summer of 2006 aboard the NOAA R/V Gordon Gunter. These included visual cetacean survey data collected along with physical data at depth via expendable bathythermograph (XBT), and conductivity-temperature-depth (CTD) instrumentation. Additionally, continual surface data were collected via the ship’s flow through sensor system. Interpolations of physical data were created from collected point data using the inverse distant weighted method (IDW) to estimate the spatial distribution of physical data within the area of interest. Interpolated physical data, as well as bathymetric (bottom depth and slope) data were extracted to overlaid cetacean sightings, so that each sighting had an associated value for nine potentially significant physical habitat parameters. A grid containing 5x5 km grid cells was created over the study area and cetacean sightings along with the values for each associated habitat parameter were summarized in each grid cell. Redundant parameters were reduced, resulting in a full model containing temperature at 50 m depth, mixed layer depth, bottom depth, slope, surface temperature, and surface salinity. GAMs were fit for each species based on these six potentially significant parameters. The resultant fit models for each species predicted the number of individuals per km2 based on a unique combination of environmental parameters. Spatial prediction grids were created based on the significant habitat parameters for each species to illustrate the GAM outputs and to indicate predicted regions of high density. Predictions were consistent with observed sightings. Sperm whale distribution was predicted by a combination of depth, sea surface temperature, and sea surface salinity. The model for pilot whales included bottom slope, and temperature at 50 m depth. It also indicated that mixed layer depth, bottom depth and surface salinity contributed to group size. Similarly, temperature at 50 m depth was significant for Atlantic spotted dolphins. Predicted bottlenose dolphin distribution was determined by a combination of bottom slope, surface salinity, and temperature at 50 m depth, with mixed layer depth contributing to group size. Distribution is most likely a sign of prey availability and ecological implications can be drawn from the habitat parameters associated with each species. For example, regions of high slope can indicate zones of upwelling, enhanced vertical mixing and prey availability throughout the water column. Furthermore, surface temperature and salinity can be indicative of patchy zones of productivity where potential prey aggregations occur. The benefits of these models is that collected point data can be used to expand our knowledge of potential cetacean “hotspots” based on associations with physical parameters. Data collection for abundance estimates, higher resolution studies, and future habitat surveys can be adjusted based on these model predictions. Furthermore, predictive habitat models can be used to establish Marine Protected Areas with boundaries that adapt to dynamic oceanographic features reflecting potential cetacean mobility. This can be valuable for the advancement of cetacean conservation efforts and to limit potential vessel and fisheries interactions with cetaceans, which may pose a threat to the sustainability of cetacean populations.
64

ENABLING LARGE-SCALE HYDROLOGIC AND HYDRAULIC MODELING THROUGH IMPROVED TOPOGRAPHIC REPRESENTATION

Sayan Dey (7444328) 19 December 2021 (has links)
<p>Topography is one of the primary drivers of physical processes in the rivers and floodplains. Advances in remote-sensing and survey techniques have provided high-resolution representation of the floodplains but information regarding the 3D representation of river channels (commonly known as river bathymetry) is sparsely available. Field surveys along an entire river network in a watershed remains infeasible and algorithms for estimating simple but effective characterization of river channel geometry are hindered by an incomplete understanding of the role of river bathymetry in surface and subsurface processes. </p> <p> The first objective of this dissertation develops an automated framework – System for Producing RIver Network Geometry (SPRING) for improving the geospatial descriptors of a river network. The tool takes as input the DEM and erroneous river centerline to produce spatially consistent river centerlines, banks, and an improved representation of river channel geometry. SPRING can process entire river networks and is not limited single reach applications. The proposed framework is flexible in terms of data requirements, resolution of output datasets and user preferences. It has a user-friendly graphic user interface (GUI) and is appropriate for large-scale applications since it requires minimal user input.</p> <p> A better understanding of the role of bathymetric characteristics in surface-subsurface hydrology and hydrodynamics can facilitate an efficient incorporation of river bathymetry in large river networks. The second objective explores the level of bathymetric detail required for accurately simulating surface and subsurface processes by developing four bathymetric representations using SPRING with reducing level of detail. These bathymetric configurations are simulated using a physically based tightly coupled hydrologic and hydrodynamic model to estimate surface and subsurface fluxes in the floodplains. Comparison of fluxes for the four bathymetric configurations show that the impact of river bathymetry extends beyond surface routing to surface water – groundwater interactions. Channel conveyance capacity and thalweg elevation are the most important characteristics controlling these interactions followed by channel side slope and channel asymmetry. </p> <p> The final objective aims to develop benchmarks for bathymetric characteristics for accurately simulating flooding related physical processes. The sensitivity of surface and subsurface fluxes to error in channel conveyance capacity is investigated across reaches with varying geomorphological characteristics. SPRING is used to create six bathymetric configurations with varying range of error in channel conveyance capacity (ranging from 25% to 300%). They are simulated using a tightly coupled physically distributed model for a flood event and the estimates of water surface elevation, infiltration and lateral seepage are compared. Results show that incorporating channel conveyance capacity with an error of within 25% significantly improves the estimates of surface and subsurface fluxes as compared to those not having any bathymetric correction. For certain reaches, such as those with high drainage area (>1000km<sup>2</sup>) or low sinuosity (< 1.25), errors of up to 100% in channel conveyance capacity can still improve H&H modeling.</p>
65

Prezentace GIS pro výuku v terénu / Presentation of GIS for Field Training

Ráczová, Gabriela January 2015 (has links)
The aim of this diploma thesis is to create Geographic Information System (GIS) presentation of Jedovnice location. Created GIS presentation serve as a teaching tool for 2nd and 3rd year of Geodesy and Cartography field, Faculty of civil engineering, University of technology in Brno. Data processing was performed using Marushka Design program of Geovap group. Database entities management was processed in the SQLite Personal program. GIS presentation includes geodetic point field in specified location and tasks assignment for students. Designed system allows editing and managing of data already existed.
66

GIS turistických stezek v Orlických horách / GIS of hiking trails in the Eagle Mountains

Tomáš, Josef January 2014 (has links)
The aim of the diploma thesis was to create the functional core of geographic information system (GIS) of hiking trails in the Eagle Mountains including the spatial analysis. The first part, more theoretical, is dedicated to the brief description of the theory and initial analysis before the particular creation of GIS. In the second part, more practical, the process of the respective task is described from the data collection to data editing, creating the core of GIS, spatial analysis and final visualization.
67

Designing multimodal public transport networks using metaheuristics

Fletterman, Manuel 16 January 2009 (has links)
The public transport system in South Africa is in a precarious state, capturing no more than 50% of the passenger market. The three public transport modes that are currently utilized—train, bus, and minibus-taxi—are competing for market share instead of complementing one another. Furthermore, most public transport networks have not been properly redesigned over the past three decades. Improvements were initiated reactively in the past: transit stops and routes were added or removed from the network when demand fluctuated. This reactive process has diminished the confidence of commuters in the public transport networks, forcing commuters to use private transport. A proactive redesign method is needed—one that includes all the modes of public transport, and anticipates an increase in demand and rapid development in geographic areas, while ensuring good accessibility to the network. Current network design models do not include multiple modes of public transport, and are based on the geographical layout of developed cities and their particularities, which makes them unsuitable for the South African environment with its unique land use disparities. This dissertation proposes a multimodal network design model that is capable of designing real world and large scale networks for the South African metropolitan areas. The City of Tshwane Metropolitan Municipality (CTMM) transport network area was used to develop and test the model, which consists of four components. The Geographic Information System (GIS) component has a central role in storing, manipulating, and exchanging the geographic data within the model. For the GIS the appropriate input data is identified, and a design for the geo-database is proposed. The Population Generation Algorithm (PGA) component translates the demographic data into point data representing the transit demand in the study area. The Bus Stop Placement Algorithm (BSPA) component is a metaheuristic that searches for near-optimal solutions for the placement of bus stops in the study area. A novel solution approach proposed in this dissertation uses geographic data of commuters to evaluate the bus stop placement in the study area. The Multimodal Network Design Algorithm (MNDA) component also employs a metaheuristic, enabling the design of near-optimal multimodal networks. The addition of multiple modes to the Transit Network Design Problem (TNDP) is also a novel and significant contribution. The two metaheuristic components are first tested on a test network, and subjected to a comprehensive sensitivity analysis. After identifying suitable parameter values and algorithm settings, the components are applied to the entire CTMM. / Dissertation (MSc)--University of Pretoria, 2009. / Industrial and Systems Engineering / unrestricted
68

How to make the most of open data? A travel demand and supply model for regional bicycle paths / Hur får man ut det mesta av öppna data? En modell för utbud och efterfrågan för planering av regionala cykelvägar

Cazor, Laurent January 2021 (has links)
Detta examensarbete syftar till att svara på ett av Trafikverket fastställt problem: en gemensam regional cykelplanerings process skulle göra dem billigare och mer jämförbara. De erbjuder för närvarande planerarna en modell som utvecklades av Kågeson 2007. Denna modell har formen av en rapport som ger råd om när man ska bygga en cykelväg mellan städer eller platser i en region. Ändå används den bara i endast 6 av de 21 svenska länen. Trafikverket kräver ett nytt planeringsstödverktyg, mer interaktivt och komplett än Kågeson-modellen. Några nya önskade funktioner är separationen av efterfrågan per syfte, införandet av e-cyklar, olika resesyfte och en prioritering av investeringarna.  Examensarbetet är att designa och implementera det här verktyget, även kallat Planning Support System (PSS), som syftar till att jämföra utbud och efterfrågan på cykelväg till prioritering av infrastrukturförbättringar. En huvudbegränsning för modellen är att den måste vara billig datavis, men så komplett och exakt som möjligt. Det baseras på flera öppna dataleverantörer, till exempel OpenStreetMap, den svenska nationella vägdatabasen (NVDB) eller reseundersökningar från Sverige och Nederländerna. Resultatet är en modell, uppdelad efter turändamål och typ av cykel.  Del för efterfrågeuppskattning anpassar en klassisk fyrsteg transportmodell till cykelplanering och begränsad data. För olika resändamål genereras och distribueras resor tack vare en ursprungs begränsad gravitationsmodell. Valet av cykelläge är anpassat till det faktiska resebeteendet genom logistisk regression med en binär logit-modell. Resorna tilldelas sedan nätverket med tilldelnings metoden "allt-eller-ingenting" genom Dijkstras algoritm. För att utvärdera cykelförsörjningen använde vi ett mått som heter Level of Traffic Stress (LTS), som uppskattar den potentiella användningen av en nätverkslänk för olika delar av befolkningen som en funktion av vägnätvariablerna. Prioriteringsrankningen är då förhållandet mellan mått på efterfrågan och utbud.  Detta nya verktyg implementeras med opensource Geographic Information System (GIS) som heter QGIS och med Python 3 och testas i Södermanlands län / This Master Thesis main objective is to answer a problem set by the Swedish Transport Administration: a common regional bicycle planning process would them cheaper and more comparable. They currently offer the planners a model developed by Kågeson in 2007. This model takes the form of a report which advises on when to build a bicycle path between cities or places of a region. Still, it is only used in only 6 of the 21 Swedish counties. Trafikverket requires a new planning support tool, more interactive and complete than the Kågeson model. Some new desired features are the separation of demand per purpose, the inclusion of e-bikes, different trip purposes, and a prioritization of the investments.  The Degree Project work is to design and implement this tool, also called Planning Support System (PSS), which compares supply and demand for bicycle path to prioritizing infrastructure improvements. A main constraint for the model is that it needs to be cheap data-wise, but as complete and precise as possible. It bases on several open data providers, such as OpenStreetMap, the Swedish National Road Database (NVDB), or Travel Surveys from Sweden and the Netherlands. The result is a model, disaggregated by trip purpose and type of bicycle.  The demand estimation part adapts a classic four-step transportation model to bicycle planning and limited data. For different trip purposes, trips are generated and distributed thanks to an origin-constrained gravity model. Bicycle mode choice is fit to actual travel behaviour through logistic regression with a binary logit model. The trips are then assigned to the network using the "all-or-nothing" assignment method through the Dijkstra algorithm. To evaluate bicycle supply, we used a metric called Level of Traffic Stress (LTS), which estimates the potential use of a network link by different parts of the population as a function of the road network variables. The prioritization ranking is then the ratio between demand and supply metrics.  This new tool is implemented with the opensource Geographic Information System (GIS) called QGIS and with Python 3, and it is tested on Södermanland County.
69

[en] IMPROVING THE PROFITABILITY OF A PUBLIC TELEPHONE NETWORK USING A GEOGRAPHIC INFORMATION SYSTEM / [pt] MELHORANDO A RENTABILIDADE DE UMA REDE DE TELEFONIA PÚBLICA USANDO SISTEMA DE INFORMAÇÃO GEOGRÁFICA

DANIEL DE MELLO SCHAEFER 30 October 2006 (has links)
[pt] Este trabalho aborda o problema da baixa rentabilidade dos telefones públicos de uma concessionária de serviços de telecomunicações mantidos por exigência da regulamentação e propõe uma metodologia flexível e de baixo custo para aumentar a lucratividade desse negócio. O problema tem similaridade com o problema clássico de localização de máxima cobertura de Church e ReVelle e a revisão da bibliografia revelou modelos que poderiam ser adaptados para a solução. Entretanto detalhes práticos tornam a abordagem de programação matemática inadequada. Desenvolveu-se, por isso uma metodologia mais flexível capaz de incorporar o conhecimento tácito acumulado pelos técnicos responsáveis. Essa metodologia conjuga análise econômica e geográfica da planta instalada de telefones públicos numa área urbana. A análise econômica aponta os telefones públicos elegíveis para a retirada e a análise da localização geográfica identificará dentre os telefones elegíveis, quais podem ser retirados sem violar o plano geral de metas de universalização da Anatel, o PGMU, especificamente no que tange o telefone para uso público. Para a análise geográfica é utilizado um eficiente sistema de informação geográfica disponível no mercado. Os resultados indicam que com a retirada dos telefones de baixa rentabilidade a lucratividade global da planta pode aumentar consideravelmente. Adicionalmente acredita-se que pela sua flexibilidade, a metodologia seja aplicável a qualquer área urbana, sendo capaz de levar em conta as peculiaridades de cada caso. / [en] This research addresses the problem of a concessionary of telecommunications that in compliance to regulations has to maintain a low profitability system of public telephones and proposes a low cost and flexible methodology to increase the profitability of the business. The problem presents similarity with the classic maximum coverage location problem of Church and ReVelle and a bibliographic search revealed models that could be adapted for solution. Nonetheless, practical details render a mathematical programming approach inadequate. For this reason, a more flexible methodology was developed capable of incorporating the tacit knowledge accumulated by the technical staff. This methodology combines economic and geographic analyses of the public telephones installed in an urban area. The economic analysis indicates the public phones eligible for removal, and the geographic analysis points out the ones that can actually be removed without violating the rules set by the regulatory agency. The geographic analysis uses an efficient geographic information system readily available in the market. The results indicate that by removing the low profitability phones the total profitability can be considerably improved. Moreover, it is believed that due to its flexibility, the methodology is applicable to any urban area, being capable of taking into account the peculiarities of each case.
70

Investigation of Biotic and Abiotic Factors Affecting Double-Cropped Corn (Zea mays L.) Production in Virginia

Sforza, Peter M. 03 October 2005 (has links)
Double-cropping of corn (Zea mays L.) for grain following the harvest of a small grain crop has been under evaluation in Virginia as an alternative cropping strategy (Brann and Pitman, 1997). To assess the potential constraints on late planted corn imposed by insects and diseases, double-cropped corn was evaluated in field experiments in Montgomery County, Virginia from 1998 to 2000. Factors included two near-isoline hybrids (NK4640 and NK4640Bt), insecticides at planting (tefluthrin in all years, 1998-2000; and imidacloprid in 1999 and 2000), and fungicide treatments (azoxystrobin or propiconazole). Response variables included yield, moisture at harvest, grain test weight, damage by European corn borer (Ostrinia nubilalis), damage by corn earworm (Heliothis zea), disease progress curves for gray leaf spot Cercospora zeae-maydis), and number of plants exhibiting virus symptoms. The Bt hybrid performed significantly better than the non-Bt hybrid for yield and test weight in double-cropped corn in 1998 and 2000, but not in 1999. A spatially referenced site suitability analysis was performed for full season and double-cropped corn in Virginia using weighted abiotic factors and constraints. Thornthwaite potential evapotranspiration (PET) and PET minus precipitation were used to identify areas of the state having a lower average moisture deficit during the silking months for double-cropped corn compared to full-season corn. It is concluded that double-cropped corn production is a viable option in Virginia where abiotic factors are not constraining, particularly growing season length and moisture availability during the sensitive stages of development. / Master of Science

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