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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

ADJACENT CHANNEL INTERFERENCE MEASUREMENTS WITH CPFSK AND FQPSK-B SIGNALS

Law, Eugene 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper will present measured data in an adjacent channel interference (ACI) environment for both filtered continuous phase frequency shift keying (CPFSK) and Feher’s patented quadrature phase shift keying (FQPSK-B) [1]. The quantity measured was bit error probability (BEP) versus signal energy per bit to noise power spectral density ratio (E(b)/N(o)). The interferers were either CPFSK or FQPSK-B signals. The results presented in this paper will be for bit rates of 5 Mb/s, one interferer 20 dB larger than desired signal, various channel spacings, and two different telemetry receivers. The ACI test effort will collect data sets at several bit rates and with one and two interferers. The results will be useful to system designers and range operators as they attempt to maximize the number of Mb/s that can be simultaneously transmitted in the telemetry bands.
62

Planting Methods for Small Grains in Arizona

Ottman, Michael 03 1900 (has links)
2 pp. / Self seeding, planting equipment, planting into stubble, row spacing, bed vs flat planting, planting into moisture vs. irrigation up, and planting direction are discussed.
63

POPULATION BIOLOGY OF DESERT ANNUAL PLANTS.

INOUYE, RICHARD SABURO. January 1982 (has links)
Germination of seeds of desert annual plants is reduced where there are high densities of annual seedlings. This is interpreted as a response by seeds to avoid a severe biotic environment in which growth rate and fecundity are likely to be reduced by larger established competitors. This density-dependent germination response is due primarily to reduced germination of small-seeded annuals where densities of large-seeded annuals are high. Because of this germination response, and because of competition at the plant stage, large-seeded annuals could, in the absence of significant levels of predation by seed-eating rodents, dominate the annual plant community to a much greater extent than is commonly observed. By reducing densities of large-seeded annuals, rodents allow densities of small-seeded annuals to increase and thus exert a positive indirect effect on granivorous ants. Seed-eating rodents and a parasitic fungus both prey on Erodium cicutarium, a dominant annual plant. These two unrelated predators significantly influence each other's densities by their use of a common prey species. Dispersal of desert annual seeds that successfully germinate is apparently not as widespread as is suggested by observations that some desert annual seeds are redistributed throughout the year by wind and water. Removal of plants during seed set significantly reduced densities of seedlings on sample plots the next year.
64

Effect of Row Spacing on Cotton Yield

Patterson, Lloyd, Massey, Garry 02 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
65

Effect of Row Width and Plant Spacing on Yield and Sucrose Concentration of Sugarbeets

Nelson, J. M. 01 1900 (has links)
No description available.
66

Effect of Spacing in 14-26-Inch Rows on Production of Fall Planted Sugarbeets

Nelson, J. M. 01 1900 (has links)
No description available.
67

Efeito do espaçamento e arranjo de plantio na produtividade e uniformidade de clones de Eucalyptus na região nordeste do Estado de São Paulo / Spacing and layout effects on the productivity and uniformity of clonal Eucalyptus in northeastern of São Paulo State

Silva, Claudio Roberto da 13 December 2005 (has links)
A escolha do espaçamento de plantio, para uma determinada espécie ou clone, em silvicultura é de alta relevância por condicionar a quantidade de recursos naturais disponíveis ao crescimento de cada árvore. Isto influencia as taxas de crescimento e sobrevivência das plantas e a produtividade de madeira por hectare, afetando as práticas de manejo e colheita e, conseqüentemente, os custos de produção florestal. Adicionalmente, há a necessidade de se definir o arranjo de plantio, ou retangularidade (razão entre as distâncias entrelinhas e entreplantas), sendo que aqueles com maior distância entrelinhas possuem maior apelo operacional por reduzirem os custos de preparo de solo ou da colheita da madeira. No entanto, teoricamente, o aumento da retangularidade deve diminuir a produtividade e uniformidade das florestas por reduzir a interceptação de luz e acelerar a estratificação das árvores, além de aumentar os riscos de matocompetição e danos causados por ventos. Assim, o presente trabalho buscou avaliar os efeitos de diferentes espaçamentos e arranjos de plantio na produtividade e uniformidade de dois clones de Eucalyptus selecionados para a região nordeste do Estado de São Paulo. O ensaio foi instalado em outubro de 1998, no município de Altinópolis-SP e consistiu de um fatorial completo 2 x 3 x 3, com 4 repetições, com dois materiais genéticos (clones de E.grandis x urophylla C041 e C219), três espaçamentos (6,0, 10,5 e 15,0 m² planta-1) e três arranjos, com distâncias entrelinhas de 3,0 m (3,00 x 2,00, 3,00 x 3,50 e 3,00 x 5,00), 6,0 (6,00 x 1,00, 6,00 x 1,75 e 6,00 x 2,50 ) e 9,0 metros (9,00 x 0.67, 9,00 x 1,17 e 9,00 x 1,67). Cada parcela teve uma área total de 900 m², com número de árvores e áreas úteis variáveis de 12 a 78 plantas, e de 180 a 468 m², totalizando 6,48 ha de ensaio. As avaliações dendrométricas foram realizadas aos 1,0, 1,5, 3,0, 4,0, 5,0 e 6,0 anos, e a biomassa da parte aérea (folhas, galhos, casca e lenho) foi avaliada ao final da rotação. Aos 6 anos, o clone C041 foi 11% mais produtivo em volume e 5% mais produtivo em biomassa de lenho do que o clone C219, com incrementos médios anuais (IMA) de 33,8 e 30,5 m³ ha-1 ano-1, respectivamente. Esta menor produtividade do C219 deveu-se a sua significativa maior susceptibilidade à quebra pelo vento, notadamente no arranjo de 9 metros. Para ambos os clones, verificou-se maior produção, em volume e biomassa de lenho no espaçamento de 6,0 m², com valores médios de 212 m3 ha-1 e 92 Mg ha-1, com reduções de 10% e 18% na produção para os espaçamentos de 10,5 e 15,0 m2 planta-1. Houve redução da produtividade com o aumento das distâncias entrelinhas, e o arranjo de 3 metros, com 34.0 m3 ha-1 ano-1 e 14.6 Mg ha-1 ano-1, foi 16% superior ao arranjo de 9 metros. Obteve-se um modelo de predição da produtividade, por clone, em função do espaçamento e do arranjo do plantio. Finalmente, observou-se a redução da uniformidade entre árvores clonais com a idade, com a redução do espaçamento e com o aumento da retangularidade. / Defining initial spacing for tree species, or clones, is relevant in silviculture because determines the amount of natural resources available for each tree growth. This influences tree growth rates and survival, and the final wood production, which affects the forest management and harvesting practices and, consequently, the forest production cost. Besides spacing, it is also necessary to define the plantation layout, or rectangularity (between-row to between-plants ratio), and the ones with larger betweenrow distance tend to be select by operational areas due to their low soil preparation or harvest costs. However, theoretically, the increase in rectangularity should reduce productivity and forest uniformity due to the reduction in light interception and the speed up of forest stratification, and can also increase weed competition and wind damage risks. This study was carried out to evaluate the spacing and layout effects on the productivity and uniformity of two Eucalyptus clones in the northeastern of Sao Paulo State. A complete 2 x 3 x 3 factorial design, with four repetitions, was installed in October 1998 in Altinopolis, with 2 clones (C041 and C219), 3 spacings (6,0, 10,5 and 15,0 m² tree-1) and 3 layouts with between-row distances of 3,0 m (3,00 x 2,00, 3,00 x 3,50 and 3,00 x 5,00), 6,0 m (6,00 x 1,00, 6,00 x 1,75 and 6,00 x 2,50 ) and 9,0 m (9,00 x 0.67, 9,00 x 1,17 and 9,00 x 1,67). Each plot had a total area of 900 m², with measured trees and areas ranging from 12 to 78, and 180 to 468 m², totalizing 6,48 ha. DBH and height measurements were done at 1.0, 1.5, 3.0, 4.0, 5.0 and 6.0 years-old, and aboveground biomass (leaves, branches, bark and stem) quantification at the end of the rotation. At 6 years-old, clone C041 was 11% more productive in volume and 5% more productive in stem biomass than clone C219, with mean anual increments (MAI) of 33.8 and 30.5 m³ ha-1 yr-1, respectively. Clone C219 was less productive due to its higher susceptibility to wind damage, mainly at 9 m layouts. For both clones, the 6,0 m² tree-1 spacing showed the larger production, 212 m3 ha-1 and 92 Mg ha-1, with a drop of 10% and 18% for the 10,5 and 15,0 m2 tree-1 spacing. Forest yield reduced with the increase in between-row spacing, and the 3 m layout, with 34.0 m3 ha-1 yr-1 and 14.6 Mg ha-1 yr-1, was 16% superior to the 9 m one. Yield prediction regression, per clone, was obtained as a function of spacing and layout. A reduction in forest uniformity among trees increased with increasing age, lower spacing and higher rectangularity.
68

Corn (Zea mays L.) yield and water use as influenced by irrigation level, nitrogen fertilization, and plant population

Ba Kufimfutu, Bakelana January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
69

Produtividade e qualidade de híbridos de tomateiro do segmento salada de crescimento semideterminado em função de sistemas de poda e espaçamento / Yield and quality of tomato hybrids of standard segment of semi-determinate growth habit in function of pruning system and spacing

Santos, Leandro Valerim dos 12 July 2017 (has links)
Atualmente a tomaticultura brasileira ostenta o título de cultivo com o maior custo de produção médio no país. Dentre algumas alternativas a fim de minimizar os elevados gastos está o uso de híbridos de crescimento semideterminado em sistema de meia-estaca, devido a menor necessidade de podas, insumos e mão de obra. Realizaram-se dois experimentos, em condições de campo aberto, com os objetivos de (a) determinar o efeito de diferentes sistemas de poda (P1, P2 e P3) e distintos espaçamentos entre plantas (E1 e E2) sobre a produção e seus componentes para o híbrido Silvety, de hábito de crescimento semideterminado do segmento Salada Longa Vida (SLV) (Experimento 1); e (b) avaliar o efeito de distintos sistemas de poda (P1 e P2) sobre a produção e seus componentes para os híbridos Silvety, Sagatan e H003, de hábito de crescimento semideterminado do segmento SLV (Experimento 2). Em ambos os experimentos adotou-se o delineamento em blocos ao acaso com os tratamentos em esquema fatorial 3 x 2 e quatro repetições. O experimento 1 foi conduzido em Jacuí, MG, de maio de 2015 a novembro de 2015, já o experimento 2 foi conduzido em Holambra, SP, de fevereiro de 2016 a agosto de 2016. Avaliaram-se o número total de frutos (NTF), a produção total por parcela (PTP), o número de frutos comercializáveis (NFC), a produção comercial (PCO), a produção por planta (PPP), a massa média dos frutos (MMF), o número de frutos por classe AAA, AA e A (NAAA, NAA e NA), a massa de frutos por classe AAA, AA e A (MAAA, MAA e MA), o número de hastes (NH) o número de inflorescências (NI), o número de frutos por inflorescência (NFI), o número de frutos com rachaduras cuticulares (CUT), o número de frutos ocos (OCO) e o número de frutos manchados (MAN). Nas condições em que os experimentos foram conduzidos e de acordo com os resultados obtidos conclui-se que no experimento 1, a poda P2e o espaçamento E1 mostraram-se os mais indicados para o híbrido Silvety. No experimento 2, novamente, a poda P2 mostrou ser a mais recomendada para os híbridos Silvety, Sagatan e H003. / Currently, the Brazilian tomato crop holds the title with the highest average cost of production in the country. Among the alternatives to minimize the high expenses, is the use of hybrids with semi-determinate growth habit in a training system of \"half-stakes\", due to the less need of pruning, inputs and labor. Two experiments were carried out under open field conditions, aiming to (a) to determine the effect of different pruning system (P1, P2 and P3) and spacing between plants (E1 and E2) on the production and its components for the Silvety hybrid, of semi-determinate growth habit of varietal segment Salad Extended Shelf Life (SLV) (Experiment 1), and (b) to evaluate the effect of pruning system (P1 and P2) on the production and its components for the Silvety, Sagatan and H003 hybrids, of semi- determinate growth habit of segment SLV (Experiment 2). In both experiments it was adopted the randomized block design with the treatments in a 3 x 2 factorial scheme, and four replications. Experiment 1 was conducted in Jacuí, MG, from May 2015 to November 2015, and Experiment 2 was conducted in Holambra, SP, from February 2016 to August 2016. There were assessed the total number of fruits (NTF), the total production per plot (PTP), the number of commercial fruits (NFC), the commercial production (PCO), the production per plant (PPP), the average mass of fruits (MMF), the number of fruits per classes AAA,AA and A (NAAA, NAA and NA), the mass of fruits per classes AAA, AA and A (MAAA, MAA and MA), the number of stems (NH), the number of clusters (NI), number of fruits per cluster (NFI), number of fruits with micro-cracking (CUT), number of hollow fruits (OCO), number of fruits with blotchy (MAN). Under the conditions that the trials were conducted and according to the results obtained, it was concluded that in experiment 1, the pruning system P2 and E1 spacing were the most suitable for Silvety hybrid. In experiment 2, again, the pruning system P2 showed to be the most recommended for Silvety, Sagatan and H003 hybrids.
70

Efeito do espaçamento e arranjo de plantio na produtividade e uniformidade de clones de Eucalyptus na região nordeste do Estado de São Paulo / Spacing and layout effects on the productivity and uniformity of clonal Eucalyptus in northeastern of São Paulo State

Claudio Roberto da Silva 13 December 2005 (has links)
A escolha do espaçamento de plantio, para uma determinada espécie ou clone, em silvicultura é de alta relevância por condicionar a quantidade de recursos naturais disponíveis ao crescimento de cada árvore. Isto influencia as taxas de crescimento e sobrevivência das plantas e a produtividade de madeira por hectare, afetando as práticas de manejo e colheita e, conseqüentemente, os custos de produção florestal. Adicionalmente, há a necessidade de se definir o arranjo de plantio, ou retangularidade (razão entre as distâncias entrelinhas e entreplantas), sendo que aqueles com maior distância entrelinhas possuem maior apelo operacional por reduzirem os custos de preparo de solo ou da colheita da madeira. No entanto, teoricamente, o aumento da retangularidade deve diminuir a produtividade e uniformidade das florestas por reduzir a interceptação de luz e acelerar a estratificação das árvores, além de aumentar os riscos de matocompetição e danos causados por ventos. Assim, o presente trabalho buscou avaliar os efeitos de diferentes espaçamentos e arranjos de plantio na produtividade e uniformidade de dois clones de Eucalyptus selecionados para a região nordeste do Estado de São Paulo. O ensaio foi instalado em outubro de 1998, no município de Altinópolis-SP e consistiu de um fatorial completo 2 x 3 x 3, com 4 repetições, com dois materiais genéticos (clones de E.grandis x urophylla C041 e C219), três espaçamentos (6,0, 10,5 e 15,0 m² planta-1) e três arranjos, com distâncias entrelinhas de 3,0 m (3,00 x 2,00, 3,00 x 3,50 e 3,00 x 5,00), 6,0 (6,00 x 1,00, 6,00 x 1,75 e 6,00 x 2,50 ) e 9,0 metros (9,00 x 0.67, 9,00 x 1,17 e 9,00 x 1,67). Cada parcela teve uma área total de 900 m², com número de árvores e áreas úteis variáveis de 12 a 78 plantas, e de 180 a 468 m², totalizando 6,48 ha de ensaio. As avaliações dendrométricas foram realizadas aos 1,0, 1,5, 3,0, 4,0, 5,0 e 6,0 anos, e a biomassa da parte aérea (folhas, galhos, casca e lenho) foi avaliada ao final da rotação. Aos 6 anos, o clone C041 foi 11% mais produtivo em volume e 5% mais produtivo em biomassa de lenho do que o clone C219, com incrementos médios anuais (IMA) de 33,8 e 30,5 m³ ha-1 ano-1, respectivamente. Esta menor produtividade do C219 deveu-se a sua significativa maior susceptibilidade à quebra pelo vento, notadamente no arranjo de 9 metros. Para ambos os clones, verificou-se maior produção, em volume e biomassa de lenho no espaçamento de 6,0 m², com valores médios de 212 m3 ha-1 e 92 Mg ha-1, com reduções de 10% e 18% na produção para os espaçamentos de 10,5 e 15,0 m2 planta-1. Houve redução da produtividade com o aumento das distâncias entrelinhas, e o arranjo de 3 metros, com 34.0 m3 ha-1 ano-1 e 14.6 Mg ha-1 ano-1, foi 16% superior ao arranjo de 9 metros. Obteve-se um modelo de predição da produtividade, por clone, em função do espaçamento e do arranjo do plantio. Finalmente, observou-se a redução da uniformidade entre árvores clonais com a idade, com a redução do espaçamento e com o aumento da retangularidade. / Defining initial spacing for tree species, or clones, is relevant in silviculture because determines the amount of natural resources available for each tree growth. This influences tree growth rates and survival, and the final wood production, which affects the forest management and harvesting practices and, consequently, the forest production cost. Besides spacing, it is also necessary to define the plantation layout, or rectangularity (between-row to between-plants ratio), and the ones with larger betweenrow distance tend to be select by operational areas due to their low soil preparation or harvest costs. However, theoretically, the increase in rectangularity should reduce productivity and forest uniformity due to the reduction in light interception and the speed up of forest stratification, and can also increase weed competition and wind damage risks. This study was carried out to evaluate the spacing and layout effects on the productivity and uniformity of two Eucalyptus clones in the northeastern of Sao Paulo State. A complete 2 x 3 x 3 factorial design, with four repetitions, was installed in October 1998 in Altinopolis, with 2 clones (C041 and C219), 3 spacings (6,0, 10,5 and 15,0 m² tree-1) and 3 layouts with between-row distances of 3,0 m (3,00 x 2,00, 3,00 x 3,50 and 3,00 x 5,00), 6,0 m (6,00 x 1,00, 6,00 x 1,75 and 6,00 x 2,50 ) and 9,0 m (9,00 x 0.67, 9,00 x 1,17 and 9,00 x 1,67). Each plot had a total area of 900 m², with measured trees and areas ranging from 12 to 78, and 180 to 468 m², totalizing 6,48 ha. DBH and height measurements were done at 1.0, 1.5, 3.0, 4.0, 5.0 and 6.0 years-old, and aboveground biomass (leaves, branches, bark and stem) quantification at the end of the rotation. At 6 years-old, clone C041 was 11% more productive in volume and 5% more productive in stem biomass than clone C219, with mean anual increments (MAI) of 33.8 and 30.5 m³ ha-1 yr-1, respectively. Clone C219 was less productive due to its higher susceptibility to wind damage, mainly at 9 m layouts. For both clones, the 6,0 m² tree-1 spacing showed the larger production, 212 m3 ha-1 and 92 Mg ha-1, with a drop of 10% and 18% for the 10,5 and 15,0 m2 tree-1 spacing. Forest yield reduced with the increase in between-row spacing, and the 3 m layout, with 34.0 m3 ha-1 yr-1 and 14.6 Mg ha-1 yr-1, was 16% superior to the 9 m one. Yield prediction regression, per clone, was obtained as a function of spacing and layout. A reduction in forest uniformity among trees increased with increasing age, lower spacing and higher rectangularity.

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