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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.
231

THE DESIGN AND VALIDATION OF A COMPUTATIONAL MODEL OF THE HUMAN WRIST JOINT

Mir, Afsarul 07 May 2013 (has links)
Advancements in computational capabilities have allowed researchers to turn towards modeling as an efficient tool to replicate and predict outcomes of complex systems. Computational models of the musculoskeletal system have gone through various iterations with early versions employing dramatic simplifications. In this work, a three-dimensional computational model of the wrist joint was developed. It accurately recreated the skeletal structures of the hand and wrist and represented the constraints imposed by soft tissue structures like ligaments, tendons, and other surrounding tissues. It was developed to function as a tool to investigate the biomechanical contributions of structures and the kinematic response of the wrist joint. The model was created with the use of a commercially available computer-aided design software employing the rigid body modeling methodology. It was validated against three different cadaveric experimental studies which investigated changes in biomechanical response following radioscapholunate fusion and proximal row carpectomy procedures. The kinematic simulations performed by the model demonstrated quantitatively accurate responses for the range of motions for both surgical procedures. It also provided some understanding to the trends in carpal bone contact force changes observed in surgically altered specimens. The model provided additional insight into the importance of structures like the triangular fibrocartilage and the capsular retinacular structures, both of which are currently not very well understood. As better understanding of components of the wrist joint is achieved, this model could function as an important tool in preoperative planning and generating individualized treatment regiments.
232

Multi-hazard modelling of dual row retaining walls

Madabhushi, Srikanth Satyanarayana Chakrapani January 2018 (has links)
The recent 2011 Tōhoku earthquake and tsunami served as a stark reminder of the destructive capabilities of such combined events. Civil Engineers are increasingly tasked with protecting coastal populations and infrastructure against more severe multi-hazard events. Whilst the protective measures must be robust, their deployment over long stretches of coastline necessitates an economical and environmentally friendly design. The dual row retaining wall concept, which features two parallel sheet pile walls with a sand infill between them and tie rods connecting the wall heads, is potentially an efficient and resilient system in the face of both earthquake and tsunami loading. Optimal use of the soil's strength and stiffness as part of the structural system is an elegant geotechnical solution which could also be applied to harbours or elevated roads. However, both the static equilibrium and dynamic response of these types of constructions are not well understood and raise many academic and practical challenges. A combination of centrifuge and numerical modelling was utilised to investigate the problem. Studying the mechanics of the walls in dry sand from the soil stresses to the system displacements revealed the complex nature of the soil structure interaction. Increased wall flexibility can allow more utilisation of the soil's plastic capacity without necessarily increasing the total displacements. Recognising the dynamically varying vertical effective stresses promotes a purer understanding of the earth pressures mobilised around the walls and may encourage a move away from historically used dynamic earth pressure coefficients. In a similar vein, the proposed modified Winkler method can form the basis of an efficient preliminary design tool for practice with a reduced disconnect between the wall movements and mobilised soil stresses. When founded in liquefiable soil and subjected to harmonic base motion, the dual row walls were resilient to catastrophic collapse and only accrued deformation in a ratcheting fashion. The experiments and numerical simulations highlighted the importance of relative suction between the walls, shear-induced dilation and regained strength outside the walls and partial drainage in the co-seismic period. The use of surrogate modelling to automatically optimise parameter selection for the advanced constitutive model was successfully explored. Ultimately, focussing on the mechanics of the dual row walls has helped further the academic and practical understanding of these complex but life-saving systems.
233

Produ??o org?nica de tomateiro tipo "cereja": compara??o entre cultivares, espa?amentos e sistemas de condu??o da cultura / Organic production of cherry tomatoes: cultivar comparison, plant densities and pruning regimes.

Azevedo, Vlamir Fortes de 17 February 2006 (has links)
Made available in DSpace on 2016-04-28T14:58:33Z (GMT). No. of bitstreams: 1 2006- Vlamir Fortes de Azevedo.pdf: 2176373 bytes, checksum: 3bbb1382e86e5d66a9e847d2c49e7275 (MD5) Previous issue date: 2006-02-17 / Tomato plants are highly susceptible to a great number of pests and diseases . This is a constraint to organic production, especially under field conditions. New technologies should be developed to improve organic tomato yields and reduce disease incidence. Row spacing and pruning regimes are two aspects which may be targeted to achieve these goals. Since cherry-type tomatoes are small, size variation resulting from pruning, will not significantly affect market value. The objective of this dissertation was to evaluate the effect of the number of stems per plant (through pruning) and plant densities on the yields and fruit quality of cherry-type tomatoes. Also, the labor required to prune the plants was estimated. Two experiments were performed at the experimental field of Departamento de Fitotecnia, Universidade Federal Rural do Rio de Janeiro, Serop?dica-RJ in the Spring-Summer 2004 and Fall/Winter 2005. The first experiment evaluated the effect of three pruning regimes (free growth, one stem per plant and two stems per plant) three plant densities (1.5 X 0,4m,1.5 X 0,6m and 1.5 X 0,8 m) and two cultivars (hybrid Super-Sweet and a local self pollinated - Perinha ). The second evaluated the effects of three pruning regimes (free growth, two stem per plant and three stems per plant and two cultivars (hybrid Super-Sweet and a self pollinated - A ). The spacing used was 1.0 X 0.6m. In the first experiment, fruit yields were equivalent on the free growth and the two stems treatments. The free growth treatment had lower labor cost, since no pruning was done. In the second experiment, the number of harvests was lower compared to the previous experiment, since a severe occurrence of blight occured. Higher yields were achieved on the three stem treatment, although a higher labor cost was associatesd to this treatment. / O tomateiro ? uma esp?cie altamente suscet?vel a um grande n?mero de pragas e doen?as, o que dificulta o seu cultivo em sistemas org?nicos de produ??o, principalmente quando conduzida em ambiente n?o-protegido. Assim, novas tecnologias que possam vir a viabilizar o seu cultivo em sistemas org?nicos devem ser testadas, visando n?o s? o aumento da produ??o, como tamb?m a redu??o dos problemas fitossanit?rios. Entre os fatores que podem ser trabalhados est?o o espa?amento e a elimina??o sistem?tica das hastes laterais, pr?tica esta conhecida como desbrota , deixando-se uma ou mais hastes por planta. Como o grupo do tomate cereja apresenta frutos pequenos, o tamanho do fruto n?o afeta significativamente a sua valoriza??o no mercado. O objetivo do presente trabalho foi avaliar o efeito do n?mero de hastes por planta, combinado com diferentes espa?amentos, sobre a produtividade e a qualidade de frutos de tomate tipo cereja e o gasto com m?o-de-obra para se efetuar a desbrota. Para tanto, foram realizados dois ensaios no Campo Experimental da Horticultura do Departamento de Fitotecnia da Universidade Federal Rural do Rio de Janeiro, em Serop?dica-RJ, nos per?odos de primavera-ver?o de 2004 e outono-inverno de 2005. No primeiro ensaio, foram avaliados os efeitos da combina??o de tr?s formas de condu??o (sem tutoramento e sem limita??o do n?mero de hastes por planta; tutoramento e condu??o de uma haste por planta e, tutoramento e condu??o de duas hastes por planta), tr?s espa?amentos entre plantas (0,4, 0,6 e 0,8 m) e duas cultivares de tomate cereja, o h?brido Super-Sweet e a variedade Perinha . O espa?amento entre linhas utilizado foi 1,5 m. No segundo ensaio, foram avaliados os efeitos da combina??o entre tr?s formas de condu??o (sem tutoramento e sem limita??o do n?mero de hastes por planta; tutoramento e condu??o de duas hastes por planta e, tutoramento e condu??o de tr?s hastes por planta) e duas cultivares de tomate cereja, o h?brido Super-Sweet e variedade A . O espa?amento adotado foi de 0,6 m entre plantas e 1,0 m entre linhas. No cultivo realizado no per?odo de primavera-ver?o, observou-se que o sistema n?o tutorado apresentou produtividade de frutos comerciais igual estatisticamente ? do tratamento onde as plantas foram conduzidas sob tutoramento e mantendo-se duas hastes por planta. O tratamento onde n?o foi feita a condu??o das plantas apresentou, ainda, menor custo de produ??o, decorrente do fato de n?o se ter gasto m?o-de-obra para a pr?tica da desbrota. No cultivo realizado no per?odo de outono-inverno, no entanto, observou-se redu??o acentuada do n?mero de colheitas neste sis tema devido, principalmente, ao ataque severo de requeima. Neste mesmo per?odo, constatou-se que o sistema de condu??o com tr?s hastes foi o que proporcionou maior produtividade de frutos comerciais, por?m com maior custo de produ??o devido ao aumento do gasto com m?o-de-obra para realiza??o da referida opera??o.
234

Influência do espaçamento, população de plantas e hí­bridos na intensidade de doenças e fatores de produção de milho safrinha / Influence of row spacing, plant population and hybrids on disease intensity and production factors of short season corn

Fontoura, Darci da 25 November 2005 (has links)
Made available in DSpace on 2017-07-10T17:37:03Z (GMT). No. of bitstreams: 1 Darci da Fontoura.pdf: 826056 bytes, checksum: 1b3391a06601ecc47dcf500fcd4942db (MD5) Previous issue date: 2005-11-25 / Although the safrinha (short season) corn area had almost a tenfold increase during the last 15 years, few studies were reported on this specific environment. The objective of the current study was to evaluate the effect of the spatial arrangement created by row spacing or by plant population on corn disease intensity in the safrinha environment. The experiment was installed in Toledo/PR for two consecutive years, 2004 and 2005. It was a randomized complete block design with 4 replications, on a factorial scheme with hybrid as the first factor (X1392D, 30F80, 30K75 and 30P70) and row spacing (38 cm, mix with 38 and 76 cm or 76 cm) or plant population (45, 60 and 75 thousand plants ha-1) as the second factor. The hybrids were selected in order to fill the following requirements: two of them had erect leaf architecture and the other two had horizontal leaf architecture, besides a different tolerance level for the main corn diseases. The incidence and severity of the leaf, stalk and ear pathogenic fungus, the incidence of generic parameters as kernel rot, root lodging, stalk lodging, besides the production factors and productivity were evaluated. Although higher plant populations and narrower row spacing resulted in higher disease intensity, there was a tendency of better yields under these treatments. On the other hand, it was dependant on the hybrid and climate condition of each growing year. The internal temperature of each plot was not affected by the spatial arrangement, however the leaf architecture affected the maximum temperature, even though it was not directly related to the disease intensity / Apesar da área de milho safrinha ter aumentado em aproximadamente dez vezes nos últimos 15 anos, poucos estudos foram relatados nesse ambiente específico. O presente trabalho teve como objetivo avaliar o efeito do arranjo espacial gerado pelo espaçamento entre linhas e pela população de plantas na intensidade de doenças em milho safrinha. O experimento foi conduzido em Toledo/PR por dois anos consecutivos, nas safrinhas de 2004 e de 2005. O delineamento experimental foi em blocos casualizados com quatro repetições, em esquema fatorial, tendo como primeiro fator o híbrido (X1392D, 30F80, 30K75 e 30P70) e como segundo fator o espaçamento entre linhas (38 cm, misto com 38 e 76 cm na mesma parcela ou 76 cm) ou a população de plantas (45, 60 e 75 mil plantas ha-1). Os híbridos foram escolhidos de forma que dois tivessem arquitetura foliar ereta e dois tivessem arquitetura foliar horizontal, além de níveis diferentes de tolerância às principais doenças. Foram avaliadas a incidência e a severidade dos principais fungos fitopatogênicos responsáveis por doenças foliares, de colmo e de espiga, a incidência de parâmetros genéricos como grão ardido, acamamento de raiz, acamamento de colmo e doenças da base do colmo, além dos fatores de produção e produtividade. O microclima gerado pela redução do espaçamento entre linhas ou pelo aumento da população de plantas resultou em aumento na intensidade de doenças de colmo e de espiga, porém não reduziu a produtividade na mesma proporção. Por outro lado, essa resposta é dependente do híbrido e da condição climática de cada ano agrícola. A temperatura interna da parcela não foi afetada pelo arranjo espacial, porém a arquitetura foliar afetou a temperatura máxima ainda que não estivesse diretamente relacionada à intensidade de doença
235

Potential value extraction from TxDOT’s right of way and other property assets

Paes, Thiago Mesquita 16 February 2012 (has links)
Many Departments of Transportation (DOTs), including Texas Department of Transportation (TxDOT), have been challenged by inadequate funding from traditional federal and state fuel taxes, increasing construction cost, aging highway system, traffic congestions, and recent natural disasters, compromising their primary mission to provide safe vehicle transportation routes with adequate capacity. Furthermore, environmental awareness and sustainability concept have strengthened and sparked debates in Congress, culminating with several regulatory policies that affect, inclusively, transportation projects. This scenario has prompted DOTs to pursue innovative ways to reduce maintenance cost (at minimum) and generate revenue (at maximum) exploiting their assets, and to meet the new regulations. Likewise, the Center of Transportation Research at The University of Texas at Austin undertook a comprehensive research study to identify and determine when, where, and under what circumstances TxDOT should pursue the implementation of which Value Extraction Application (VEA), and how to effectively recognize and involve key stakeholders. As a result, 11 VEAs were identified. In addition, a methodological framework – embedding a multi-attribute criteria analysis matrix as the decision making method - was devised to guide TxDOT throughout the process of identifying, evaluating, comparing, and selecting the most appropriate VEA while a list of stakeholders associated with each VEA and a stakeholder analysis framework was provided to help TxDOT to identify and reach out key stakeholders. / text
236

Būdvardžių darybiniai sinonimai / The use of derivative synonyms of adjectives

Kačinauskaitė, Ramunė 27 August 2009 (has links)
Būdvardžių darybiniais sinonimais laikytini iš to paties pamatinio žodžio su skirtingais darybos formantais sudaryti dariniai, kuriems būdinga ta pati darybinė reikšmė ir tapati arba artima leksinė reikšmė. Pagrindinis šio darbo tikslas – išanalizuoti būdvardžių darybinių sinonimų vartoseną. Medžiagos šaltiniu šiai analizei buvo pasirinktas Dabartinės lietuvių kalbos žodynas. Iš viso išrinkti 1556 būdvardžių dariniai, sudarytos 724 darybinių sinonimų eilės. Daugiausia priesagų vedinių – jų net 1251, t. y. 80,4% visų būdvardžių darinių. Daugiausia darybinių sinonimų eilių, kuriose sinonimiškai santykiauja du dariniai, tokių eilių – 642, t. y. net 88,7% visų darybinių sinonimų eilių. Sinoniminiai santykiai gali susiklostyti tarp 53 priesagų, 3 galūnių ir 3 priešdėlių vedinių. Iš viso buvo sudarytos 99 afiksų kombinacijos. Darbe išsamiau nagrinėtos tos darybinių sinonimų eilės, į kurias įeina dominuojančių priesagų -inis, -ingas, -uotas, -ėtas, priešdėlio apy- ir galūnės -us vediniai. Priesagų -inis, -ingas, -uotas, -ėtas, priešdėlio apy- ir galūnės -us vediniai dažnai įeina į darybinių sinonimų eiles, kuriose jie darybiškai santykiauja su kitų, t. y. retesnių, tarminių darybos afiksų bendrašakniais vediniais ir sudaro pavienes darybinių sinonimų eiles. Pavienėms eilėms būdingas kombinacijų įvairumas, sinonimiškų darinių eilėje gausumas, t. y. eilių ilgumas, ir vartosenos subtilumai. Detalesnė būdvardžių darybinių sinonimų vartosena grindžiama Dabartinės lietuvių kalbos tekstyno... [toliau žr. visą tekstą] / Derivative synonyms of adjectives are derivatives formed from the same underlying word with different derivative formatives and having the same derivative meaning and identical or very similar lexical meaning. The main aim of this paper is to analize the use of derivative synonyms of adjectives. The Dictionary of Contemporary Lithuanian has been chosen as a source material for this analysis. 1556 derivatives of adjectives have been selected and 724 rows of derivative synonyms have been formed. Derivatives of suffixes comprise the largest group (in total 1251, i. e. 80.4 % of all derivative adjectives). There are 642 rows of derivative synonyms, i. e. 88.7 % of all rows of derivative synonyms, where two derivatives correlate synonymously. Synonymous correlation can be developed among 53 suffixes, 3 endings and 3 derivatives of prefixes. In total 99 combinations of affixes have been formed. The rows of derivative synonyms which include derivatives with predominant suffixes -inis, -ingas, -uotas, -ėtas, prefix apy- and ending -us have been more deeply analysed in this paper. The derivatives of suffixes -inis, -ingas, -uotas, -ėtas, prefix apy- and ending -us often comprise those rows that derivatively correlate with other, i. e. more rare, conjugate derivatives of the afixes of dialectal derivation and compose single rows of derivative synonyms. Diversity of combinations, richness of synonymous derivatives in the row, i.e. length of rows and subtlety of the use, is typical to... [to full text]
237

Modellazione dell’impatto del cambiamento climatico sulla interazione pianta - patogeni a livello regionale nel Trentino – Italia. / MODELLING THE IMPACT OF CLIMATE CHANGE ON THE INTERACTION BETWEEN HOST AND PEST/PATHOGEN PHENOLOGIES AT REGIONAL LEVEL: 'TRENTINO' - ITALY

RINALDI, MONICA FERNANDA 21 February 2013 (has links)
Il controllo in agricoltura delle malattie causate da patogeni fungini può essere effettuato attraverso l’uso di modelli di previsione che si basano comunemente sul monitoraggio in tempo reale di una serie di variabili di input. Queste informazioni generalmente combinano dati metereologici locali con modelli matematici costruiti allo scopo di predire il rischio di malattie. Il processo decisionale si attiva quando un avvertimento sul potenziale rischio viene riconosciuto da parte dei modelli. Diversi modelli epidemiologici sono stati sviluppati e validati nel mondo. Negli Stati Uniti d’America, ad esempio, l’università della California ha sviluppato un supporto decisionale on-line per gestire la coltura secondo i principi della lotta integrata (Integrated Pest Management - IPM). Ciascun agricoltore può consultare il proprio database informativo e prendere decisioni sui trattamenti da effettuare basandosi su dati sito-specifici. Le difficoltà sorgono quando non sono disponibili dati meteorologici da stazioni poste nelle vicinanze del sito in studio o per le zone montane caratterizzate da una forte variabilità altimetrica. Inoltre i dati meteorologici disponibili possono presentarsi in formato non adeguato rispetto alle esigenze del modello previsionale. Con l’intento di avere una visione regionale e una maggiore accuratezza nella gestione del controllo delle malattie, l’obiettivo della tesi è stato l’utilizzo contemporaneo di modelli epidemiologici (Lobesia botrana e Erysiphe necator, agente causale dell’oidio della vite) con modelli fenologici (cultivar di vite Chardonnay) utilizzando parametri meteorologici come la temperatura per creare mappe a livello regionale, a frequenza giornaliera e con una risoluzione spaziale di 200 metri. L’utilizzo contemporaneo di entrambi i modelli aiuta ad essere più precisi nel consigliare interventi colturali nel periodo di sensibilità dell’ospite nei confronti del patogeno o della malattia in modo da poterne stimare il reale rischio di diffusione o insorgenza. Dopo aver calibrato e validato i modelli in Trentino-Alto Adige (Nord Italia) con dati metereologici locali, basandoci sul modello del cambiamento climatico HadAM3 dell’Hadley Centre (Pope et al., 2000),l’andamento climatico previsto è stato proiettato e statisticamente portato. in scala, utilizzando lo scenario A2 e B2. L’algoritmo statistico utilizzato per ridurre la scala giornaliera di risoluzione è chiamato “transfer function” (Eccel et al., 2009). Per completare l’analisi, è stato inoltre utilizzato lo scenario ridimensionato di ENSEMBLES attraverso l’uso di set di dati provenienti da 49 stazioni meteorologiche della FEM e dal pacchetto “RMAWGEN” (Cordano et al., 2012) creato con il software statistico R. (Gentleman et al., 1997). Per mappare i modelli è stata sviluppata una semplice piattaforma modulare WEB-GIS chiamata ENVIRO. I moduli sono “Open Source” e seguono gli standard internazionali dell’“Open Geospatial Consortium” (OGC) e sono stati implementati come segue: i) enviDB è il database per i dati spazio-temporali, ii) enviGRID permette agli utenti di navigare attraverso i dati e i modelli nello spazio e nel tempo, iii) enviMapper è l’interfaccia web per prendere le decisioni, consiste in uno stato dell’arte per mappare la vulnerabilità del cambiamento climatico a diverse scale di aggregazione nello spazio e nel tempo, iv) enviModel è l’interfaccia web per i ricercatori a cui viene fornita una piattaforma per processare e condividere modelli di rischio ambientali utilizzando il “web processing Technologies” (WPS) seguendo gli standard OGC. Con l’obiettivo di diventare ancora più accurati nelle previsioni dei volumi per i trattamenti contro insetti e malattie, in accordo con la direttiva 2009/128/EC, il seguente lavoro dimostra che il sensore LIDAR può essere utilizzato per caratterizzare la geometria della pianta della vite e stimare l’area fogliare (LAI) ad ogni stadio di crescita. Inoltre permette di calcolare il volume da applicare (Tree Row Volume -TRV) visualizzato nelle mappe 3D in GRASS. (Neteler et al., 2008, Neteler et al., 2012). / Control of agricultural pests and diseases is often based on forecasting models commonly based on real time monitoring of inputs variables. This information generally combines meteorological local databases and mathematical models designed to forecast pest and disease risk. The decision process starts when an alert or a potential risk event from the outputs of the models is issued. Epidemiological models based on local datasets have been created and validated worldwide, for example in USA, the University of California developed the online Integrated Pest Management (IPM) program where each farmer can consult with his own database and make the pest management decision based on site-specific conditions. Difficulties arise when no data from a close weather station are available, in mountain areas where weather conditions highly depend on the altimetry, or if data are not in a standard format to feed the model. In a view of having a regional vision and an increased accuracy in the pest control management, the goal of this thesis was to run contemporaneously epidemiological (the pest Lobesia botrana and the pathogen causing Powdery mildew Erysiphe necator) and phenological models (grapevine cv. chardonnay) using environmental variables as temperature and to create maps at regional level, with 200 meters of resolution and daily scale or frequency. Running both models together helps to be more precise in the sensibility period of the host versus the pest or the disease and to understand the real final risk. After calibrating and validating the models in the Trentino-Alto Adige Region (Italy) with local weather data, the forecasted climate was projected and statistically downscaled, based on the output of the Hadley Centre climate model - HadAM3 (Pope et al., 2000) under scenarios A2 and B2. The statistical downscaling algorithm was “transfer function method” (Eccel et al., 2009) at daily resolution. In order to complete the analysis, the downscaled scenario from ENSEMBLES was also used with the datasets of 49 weather stations from FEM and the “RMAWGEN” packages (Cordano et al., 2012) created for this project in R statistical open source software (Gentleman et al., 1997). In order to map the models, a friendly modular WEB-GIS platform called ENVIRO was developed. Modules are Open Source, follow international Open Geospatial Consortium (OGC) standards and were implemented as follows: i) enviDB is the database for spatial temporal data, ii) enviGRID allows users to navigate through data and model in space and time, iii) enviMapper is the web interface for decision makers, a state of the art client to map vulnerability to climate change at different aggregation scales in time and space; finally, iv) enviModel is the web interface for researchers that provides a platform to process and share environmental risk models using web geo-processing technologies (WPS) following OGC standards. With the aim of being even more accurate in pests and diseases spraying volumes and according with the Directive 2009/128/EC, the current work shows that the LIDAR sensor can be used to characterize the geometry of the grapevine and the Leaf Area Index (LAI) at each growth stage and calculate the Tree Row Volume (TRV) visualized in 3D maps in GRASS (Neteler et al., 2008, Neteler et al., 2012).
238

Vliv různé šířky řádků na výnos biomasy a obsah sušiny při pěstování čiroku / Effect of different width of rows on biomass yield and dry matter content at growing sorghum

KUBEŠ, Pavel January 2016 (has links)
The aim of this thesis was to determine the effect of row spacing on sorghum yields and dry matter. The trial was established on 29 May 2015 on land belonging to the Agricultural Cooperative Milevsko, which is situated in the corn-growing area. The trial compared four varieties of sorghum, namely Aristos, Goliath, KWS Freya and KWS Sole. The varieties were sown in different row spacings, namely 75 cm, 60 cm, 45 cm a 30 cm. The samples taken on three dates were analysed for dry matter content. Each variety showed a gradual increase in the dry matter content. During the harvest on 5 October 2015 the varieties KWS Freya and KWS Sole reached an optimal value of the dry matter when planted in all spacings. All varieties produced the highest average yield of green matter when planted in rows spaced 60 cm apart. The variety Aristos produced the highest average yield of green matter. The KWS Sole variety reached the lowest average yield of green matter when planted in rows 76 cm apart. All varieties with 60 cm row spacings, except for KWS Sole, produced the highest average yield of dry matter. The highest average yield of dry matter was reached by Aristos and the lowest by KWS Sole. The results of the one-year trial did not prove a direct connection of the effect of row spacing on dry matter. The effect of row spacing on green and dry matter yield was proved. The optimum row spacing seems to be 60 cm.
239

Desempenho agronômico de híbridos de milho em diferentes arranjos populacionais em Jaboticabal-SP

Demétrio, Cláudia de Sousa [UNESP] 26 February 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-26Bitstream added on 2014-06-13T20:58:20Z : No. of bitstreams: 1 demetrio_cs_me_jabo.pdf: 252291 bytes, checksum: 1265f694678a98b45a4678fbf67cb7f0 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O trabalho teve como objetivo avaliar a influência de espaçamentos entre as linhas e densidades populacionais, em dois híbridos de milho, no desempenho agronômico da cultura com ênfase nos componentes de produção, produtividade e composição glicídica dos grãos. O experimento foi conduzido na safra 2006/2007, em condições de campo, em Latossolo Vermelho eutrófico típico, textura argilosa, A moderado, a 21°15’22”de latitude sul e longitude 48°18’58” WGr, em Jaboticabal – SP. O delineamento experimental foi o de blocos ao acaso, compostos por 24 tratamentos, constituídos pela combinação de três espaçamentos entre as linhas (40, 60 e 80 cm) nas parcelas, dois híbridos (30K73 e 30F80) nas subparcelas, e quatro densidades populacionais (30, 50, 70 e 90 mil plantas ha-1) nas sub-subparcelas, com três repetições. As variáveis avaliadas foram: estatura de plantas, altura da 1ª espiga, n.º espigas por planta, diâmetro de colmo, acamamento e quebramento de plantas, n.º de grãos na 1ª espiga, massa de grãos na 1ª espiga, massa de mil grãos, produtividade de grãos e índice de colheita. Foram feitas análises químicas do grão para determinação do teor de sacarose, açucares redutores e amido. Verificou-se que a produtividade do milho aumentou com a redução do espaçamento entre as linhas de 80 para 40 cm, que o melhor arranjo de plantas, para os híbridos 30K73 e 30F80, nas condições de edafoclimáticas de Jaboticabal, é composto pela combinação de 40 cm de espaçamento entre as linhas e 75 e 80 mil plantas ha-1 de densidade populacional, respectivamente. Modificando o arranjo espacial de plantas de milho, a composição final de glicídios no grão não é alterada. / The present work had the objective of evaluating the influence of row spacing and population densities, in two corn hybrids, on the agronomic performance of the culture with enface on production components and productivity. The experiment was carried out in the agricultural year of 2006/2007, under field conditions, in a Typical Haplustox , clay texture, at 21°15’22” South latitude and longitude 48°18’58” W, at Jaboticabal – SP, Brazil. The experimental design was a complete randomized block, in split split-plot scheme with 24 treatments, where the plots were composed by three row spacing (40, 60 e 80 cm), the split-plots by two contrastive hybrids (30K73 ND 30F80) and the split split-plots by four population densities (30, 50, 70, e 90 thousand plants per hectare), with three replications. The following variables were evaluated: plant height, first ear height, number of ear per plant, stem diameter, plant lodging and breakage, number of grains per ear, mass of grains per ear, mass of a thousand grains, grain yield and yield index. Furthermore, grain chemical analyses were done to determine the content of saccharose, redacting sugars and starch. It was verified that corn productivity rises with the reduction of row spacing from 80 to 40 cm, that the best plant arrangement, for the hybrids 30K73 and P0F80, under Jaboticabal environment conditions, is the combination of 40 cm row spacing and 75 and 80 thousand plants per hectare, respectively. Final grain glicidic composition is not altered by the spacial arrangements of corn plants.
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Arranjo de plantas para maximizar o desempenho agronômico do milho em ambientes de alto manejo / Arrangement of plants to maximize the agronomic performance of maize in high potential of yield environments

Schmitt, Amauri 13 October 2014 (has links)
Made available in DSpace on 2016-12-06T17:42:05Z (GMT). No. of bitstreams: 1 PGPV14DA011.pdf: 1428690 bytes, checksum: 449aef7542bd13e0b624b66ceb10523f (MD5) Previous issue date: 2014-10-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The proper choice of plant arrangement is important to maximize maize grain yield. This work was carried out aiming to evaluate the best strategies to manipulate plant arrangement in order to reach grain yields higher than 18,000 kg ha-1. Four field experiments were set during the 2010/2011 and 2011/2012 growing seasons. In the first experiment, the effect of increasing plant density was assessed. The plant populations of 3, 5, 7, 9 and 11 pl m-2 were tested at two row spacing (40 and 80 cm). In the second trial, the effect of reducing row spacing was studied. Five row spacings were tested: 40, 60, 80, 100 cm and twin rows. Each row spacing was tested at two plant densities (7 and 9 pl m-2). In the third trial, plant uneven emergence at the sowing row was evaluated. Five levels of unevenness in plant emergence were studied: 0, 2.5, 5, 7.5 and 10 days. In the level 0, all seeds were sowed in the same day. In the other treatments, half seeds were sowed in day 0 and the other half 2,5, 5, 7.5 and 10 days after. It the forth trial spatial uneven plant distribution in the sowing row was simulated. Five levels of spatial unevenness were addressed: 0, 25, 50, 75 and 100 of the variation coefficient (C.V.). In the level 0, all seeds were placed at the same distance from each other in the sowing row. Uneven temporal and spatial distribution was studied at 18 19 two row spacings: 40 and 80 cm. In the first experiment, grain increased linearly with the increment in plant population from 3 to 11 pl m-2 when maize was grown with the row spacing of 40 cm. In the second trial, grain yield was greater with 9 pl m-2 than with 7 pl m-2 and row spacing did not affect the crop productivity. In the third experiment, the increase in temporal variability of plant emergence decreased grain yield when maize was grown with rows 80 cm apart. In the fourth trial, grain yield was reduced by the increment in spatial variability among plants at the sowing row when the crop was grown with the row spacing of 40 cm. The use of supra-optimum plant densities ( 9 to 11 pl m-2), associated to narrow row spacing (40 cm), are efficient strategies to manipulate plant arrangement in order to lift maize grain yield above 18,000 kg ha-1, as long as the plants are evenly distributed in space and time at the sowing rows / A escolha adequada do arranjo de plantas é importante para potencializar o rendimento de grãos do milho. Este trabalho foi conduzido com o intuito de identificar as melhores estratégias de manipulação do arranjo de plantas para alcançar tetos produtivos superiores a 18.000 kg ha-1. Foram conduzidos quatro experimentos nas safras 2010/2011 e 2011/2012. No primeiro avaliou-se o efeito do incremento na densidade de plantas sobre o desempenho agronômico do milho. Foram testadas as densidades de 3, 5, 7, 9 e 11 pl m-2, nos espaçamentos entre-linhas de 40 e 80 cm. No segundo avaliou-se o impacto da redução do espaçamento entre-linhas no potencial produtivo do milho. Foram avaliados os espaçamentos entre-linhas de 100, 80, 60 e 40 cm e o de linhas gêmeas, nas densidades de 70.000 e 90.000 pl ha-1. No terceiro quantificou-se o efeito da irregularidade temporal na emergência das plantas na linha de semeadura sobre o rendimento de grãos. Foram testados cinco níveis de desuniformidade temporal, equivalentes a 0, 2,5, 5,0, 7,5 e 10 dias. No nível 0 todas as sementes foram semeadas no mesmo dia. Nos demais níveis, metade das sementes foi semeada no dia 0 e a outra metade 2,5, 5,0, 7,5 e 10 dias após. No quarto experimento analisou-se o efeito da desuniformidade espacial na linha sobre o rendimento de grãos do milho. Foram testados cinco níveis de desuniformidade espacial, equivalentes a 0, 25, 50, 75 e 100 % do coeficiente de variação, onde o nível 0 equivale as plantas uniformemente distribuídas nos sulcos. Cada nível de desuniformidade temporal e espacial foi avaliado nos espaçamentos entre-linhas de 40 e 80 cm. No primeiro ensaio, o rendimento de grãos aumentou linearmente com o incremento na densidade de plantas no espaçamento de 0,4m entre-linhas. No segundo ensaio, os rendimentos foram maiores na densidade de 9 pl m-2 do que na de 7 pl m-2 e não houve diferenças significativas no rendimento de grãos entre os cinco espaçamentos entre-linhas. No terceiro trabalho, o aumento da variabilidade temporal das plantas na linha diminuiu o rendimento de grãos do milho quando o mesmo foi cultivado com espaçamentos entre-linhas de 80 cm. No quarto ensaio, o rendimento de grãos reduziu com o aumento do C.V na distribuição espacial de plantas quando o milho foi cultivado no espaçamento entre-linhas de 40 cm. A utilização de densidades supra-ótimas (9 a 11 pl m-2) e de espaçamento entre-linhas reduzido (40-50 cm) são estratégias efetivas de manipulação do arranjo de plantas para alcançar produtividades superiores a 18.000 kg ha-1 em lavouras com distribuição espacial e temporal uniforme das plantas na linha de semeadura

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