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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.
161

Desenvolvimento e produção do algodoeiro em função de espaçamentos e aplicação de regulador de crescimento

Ferrari, Samuel [UNESP] 15 February 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-15Bitstream added on 2014-06-13T18:39:43Z : No. of bitstreams: 1 ferrari_s_me_ilha.pdf: 549681 bytes, checksum: ae8e08d93ae07c24cca8e73a2e455280 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O cultivo do algodoeiro passou de uma cultura de pequenos e médios produtores para uma realidade alicerçada em um modelo de produção em escala, caracterizado por altas produtividades e intenso uso de insumos e mecanização. Essa mudança ocasionou uma série de alternativas nas técnicas de cultivo, sendo crescente a indagação sobre alternativas às recomendações tradicionais sobre os vários tratos culturais e práticas agronômicas tais como época de semeadura, espaçamentos, densidade de plantas e emprego de reguladores de crescimento. O objetivo deste trabalho foi avaliar a influência de diferentes espaçamentos de cultivo e aplicação ou não de regulador de crescimento sobre o desenvolvimento, acúmulo de nutrientes e produtividade do algodoeiro em região de Cerrado. O delineamento experimental foi de blocos casualizados em esquema fatorial 3x3 com 9 tratamentos e 4 repetições, constituído por três espaçamentos: 0,45m, 0,70m e 0,90m entre linhas; Aplicação de cloreto de mepiquat na dose de 1,0 L ha-1 : a- aplicação parcelada em quatro etapas, b- aplicação única aos 70 dias após a emergência e c- sem a aplicação do regulador. Foi utilizada a cultivar de algodão Deltaopal. O experimento foi instalado no município de Selvíria (MS), na Fazenda de Ensino e Pesquisa da Unesp... / The cotton crop had changed the status of production from small to large scale, characterized by high yields and intensive use of fertilizers, agrochemicals and mechanization. That change caused a series of alternatives in the cultivation techniques, being growing the inquiry on alternatives to the traditional recommendations on the several cultural treatments and such agronomic practices as sowing time, spacings, density of plants and use of growth regulators. The objective of this study was to evaluate the influence of different row spacings in the cotton crop, with or without growth regulator and its effects in the development, nutrient uptake and yield in the Cerrado zone. The experimental design was the completely blocks in a factorial scheme 3x3 with 4 replications, with three row spacings: 0.45m, 0.70m and 0.90m; Application of mepiquat chloride using the dose of 1 L ha-1: a- split application in four stages, b- single application at 70 d.a.e and c-without application of the regulator. Was utilized the Deltaopal cotton cultivar. The trial was installed in the city of Selvíria (MS) out at the experimental farm of the Sao Paulo State University - Ilha Solteira Campus, in November of 2005 and the harvest realized in April of 2006... (Complete abstract click electronic access below)
162

Aplicação de luz na faixa do vermelho-extremo em mudas e diferentes sistemas de condução do tomateiro cultivado em ambiente protegido

Hora, Rerison Catarino da [UNESP] 03 February 2003 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-02-03Bitstream added on 2014-06-13T19:59:41Z : No. of bitstreams: 1 hora_rc_me_ilha.pdf: 278731 bytes, checksum: f000da603552eea3caab3009581fa3b0 (MD5) / O ensaio foi conduzido de maio a setembro de 2002, na Fazenda de Ensino e Pesquisa da Faculdade de Engenharia/UNESP, Câmpus de Ilha Solteira, SP, tendo por objetivo avaliar a eficiência da aplicação de luz na faixa do vermelho-extremo, em mudas de tomateiro (Lycopersicon esculentum), na redução da emissão de brotação lateral das plantas, bem como estudar o adensamento e poda apical drástica, na concentração da produção de tomate, em ambiente protegido. Foram estudadas três condições de tratamento de mudas (IT - fotoperíodo natural, como testemunha; IVE - fotoperíodo natural, mais irradiação, ao final do fotoperíodo, com luz na faixa do vermelho-extremo; IV+VE - fotoperíodo natural, mais irradiação, com luz na faixa do vermelho, substituído pelo vermelho-extremo, ao final do fotoperíodo, uma semana antes do transplantio) e dois sistemas de condução da cultura, tendo como base 100.000 inflorescências/ha (SC1 - poda apical após a 5a inflorescência e 20.000 plantas/ha, no espaçamento de 1,0 m entre linhas e 0,5 m entre plantas; e SC2 - poda apical após a 2a inflorescência e 50.000 plantas/ha, no espaçamento de 1,0 m entre linhas e 0,2 m entre plantas). Adotou-se o delineamento em blocos ao acaso no esquema experimental de parcelas subdivididas, estudando-se o comportamento do híbrido Duradoro da EMBRAPA, cultivado sob ambiente protegido de dimensões 5,4 x 30,0 m, coberto com filme plástico de polietileno de 75 mm. Foram obtidas, nas avaliações das mudas, o peso seco, altura e diâmetro do caule e área foliar. Após o transplantio, realizaram-se avaliações microclimáticas, fitotécnicas, eficiência de conversão da radiação solar global incidente em matéria fresca de frutos (EC), e análise econômica de acordo com os tratamentos. Verificou-se que, o ambiente protegido, comparado ao campo aberto, reduziu a densidade de fluxo de radiação solar... . / The experiment was conducted between May and September 2002, at the Teaching and Research Farm (Ilha Solteira, São Paulo State, Brazil) of the College of Engineering of Ilha Solteira, UNESP. The main objective was to evaluate the efficiency of the application of far-red light on the reduction of emission of side shoots in tomato (Lycopersicon esculentum) seedlings, as well as to investigate the effects of plant density and drastic pruning on tomato yield under protected environment. Seedlings were exposed to three conditions: (1) natural photoperiod (control); (2) natural photoperiod plus 20 min of far-red radation at the end of the day and (3) natural photoperiod plus 20 min of radiation at the end of the day, with light at the red wave length, which was replaced by far-red radiation a week before transplanting. We also analyzed two cultivation systems, both based on 100,000 inflorescences/ha, (a) growing tip pruning after the fifth inflorescence and (SC1) (b) growing tip pruning after the second inflorescence (SC2). The experimental design was a split plot design, where we studied the performance of EMBRAPA's Duradouro hybrid, cultivated under protected environment of 5.4 x 30.0 m, with 75-mm polyethylene sheets. We evaluated plant dry weight, height, stem diameter and leaf area. After seedlings were transplanted to the field, we assayed daily the solar flux density, air temperature and air moisture. In the field we also measured growth (height and diameter of plants, number of internodes, dry weight and number of side shoots) and botanical and technological traits such as yield, total and commercial number of fruits per area, cropping period and efficiency of conversion of global incident solar radiation on fresh weight of fruits. An economical analysis was also carry out for each treatment. We verified that the solar flux... (Complete abstract, click electronic address below).
163

Arranjos espaciais na cultura da soja submetida a doses de fósforo e potássio / Spatial arrangements in soybean crop submitted to phosphorus and potassium doses

Duarte, Thiago Camilo 29 February 2016 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2016-07-29T20:31:45Z No. of bitstreams: 2 Dissertação - Tiago Camilo Duarte - 2016.pdf: 1799186 bytes, checksum: 59814a5871558965ce2ab372718e6536 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-01T13:55:17Z (GMT) No. of bitstreams: 2 Dissertação - Tiago Camilo Duarte - 2016.pdf: 1799186 bytes, checksum: 59814a5871558965ce2ab372718e6536 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-08-01T13:55:17Z (GMT). No. of bitstreams: 2 Dissertação - Tiago Camilo Duarte - 2016.pdf: 1799186 bytes, checksum: 59814a5871558965ce2ab372718e6536 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-02-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The soybeans have been broadly cultivated in Brazil and the world due to it`s food and economic importance, that boost many agroindustrial complexes. The objective of this study was evaluate the effect of spatial arrangements, simple and twin rows, associated with different fertilizing levels on the development and yield at Anta 82 RR soybean cultivar. The experiment was carried in Universidade Federal de Goiás, Regional Jataí, with 10 treatments established in a split plot randomized block design, with four replications. Each plot corresponded to one fertilizing level with P and K (0, 50, 100, 200 and 400% of recommended dose) and the sub plots were two spatial arrangements: simple (0,45 m) and twin rows ( 0,25 x 0,65 m). The recommended rate of P and K was 80 kg ha-1 of P2O5 and 80 kg ha-1 of K2O. During the development period of the culture were determined the initial population, Falker chlorophyll index, dry mass, leaf area index, cover factor and nutritional content of the index leaves. When the soybean plants was in growth stage R8 were done the following evaluations: final plant population, plant and first pod insertion height, number of pods and grains per plant, number of grains per pod, mass of thousand grains and yield. The soybean cultivar Anta 82 RR demonstrated small answer for morphological components, with the use alternative spatial arrangements. The increase of fertilizing level, even with rates 2 and 4 times higher than the recommended, allowed soybean response in grain yield for the two studied arrangements. The simple arrangement provides higher grain yield, independently of fertilizing level. / A soja tem sido amplamente cultivada no Brasil e no mundo por sua importância alimentar e econômica, que impulsiona diversos complexos agroindustriais. O objetivo desse trabalho foi avaliar o efeito de arranjos espaciais, simples e fileira dupla, associados a níveis de adubação sobre o desenvolvimento e produtividade da cultivar de soja Anta 82 RR, levando em conta parâmetros produtivos e ecofisiológicos. O experimento foi conduzido na Universidade Federal de Goiás, Regional Jataí, com o delineamento experimental constituído de 10 tratamentos estabelecidos em blocos casualizados, com parcelas subdivididas, em quatro repetições. Cada parcela correspondeu a um nível de adubação com P e K (0, 50, 100, 200 e 400% da dose recomendada) e as subparcelas a dois tipos de arranjos espaciais: simples (0,45 m) e fileira dupla (0,25 x 0,65 m). A dose recomendada de P e K foi 80 kg ha-1 de P2O5 e 80 kg ha-1 de K2O. Durante o período de desenvolvimento da cultura determinou-se a população inicial de plantas, o índice de clorofila Falker, a massa de planta seca, o índice de área foliar, o fator de cobertura e os teores nutricionais das folhas índice. Quando as plantas de soja encontravam-se no estádio R8 foram realizadas as seguintes avaliações: população final de plantas, altura de planta e inserção da primeira vagem, número de vagens e de grãos por planta, número de grãos por vagem, peso de mil grãos e produtividade. A cultivar de soja Anta 82 RR demonstrou pequena resposta para os componentes morfológicos, com o uso de arranjo espacial alternativo. O aumento no nível de adubação, mesmo com doses 2 e 4 vezes maiores que o recomendado, possibilita resposta da soja em produtividade de grãos para os dois arranjos estudados. O arranjo simples proporciona maior produtividade de grãos, independentemente do nível de adubação
164

Desempenho de híbridos de tomate de mesa em função de sistemas de condução e da densidade populacional / Performance of tomato hybrids for fresh market in relation to training systems and planting densities

Evandro da Silva Matos 17 September 2010 (has links)
Realizaram-se dois experimentos, em condições de campo, com os objetivos de (a) determinar o efeito de sistemas de condução de plantas e de tutoramento sobre a produção e seus componentes em híbridos de tomate de mesa de hábito de crescimento indeterminado dos segmentos Salada Longa Vida (SLV) e Santa Cruz (SC) (Experimento 1), e (b) avaliar o efeito do espaçamento entre plantas no sistema de condução com uma única haste tutorada com fitilho sobre a produção e seus componentes para híbridos do segmento SLV (Experimento 2). No experimento 1 adotou-se o delineamento em blocos ao acaso com os tratamentos em esquema fatorial 5 x 2, e quatro repetições, sendo avaliados três híbridos SLV e dois SC em dois sistemas de condução de plantas. No experimento 2, o delineamento utilizado também foi em blocos ao acaso, com os tratamentos em esquema fatorial 2 x 4, e quatro repetições, avaliando-se dois híbridos SLV. Os experimentos foram conduzidos em Itatiba, SP, de julho de 2007 a janeiro de 2008, e de janeiro a julho de 2009. Foram consideradas todas as plantas de cada parcela e avaliaram-se o número total frutos (NTF), a produção total por parcela (PTP), a massa de frutos descartados (MFD), o número de frutos comerciais (NFC), a produção comercial (PCO), a produção por planta (PPP), a massa média dos frutos (MMF), a massa de frutos comercializáveis nas classes AAA, AA e A, para ambos os grupos varietais, bem com o número de frutos com rachaduras radiais (RAD), com rachaduras concêntricas (CON), com lóculo aberto (LAB), manchados (MAN), ocos (OCO) e deformados (DEF). O sistema de condução de plantas com duas hastes tutoradas com bambu proporcionou incremento de NTF, NFC e PPP, para ambos os segmentos em comparação à condução de uma única planta por cova com uma haste tutorada com fitilho. O sistema de condução com bambu, para ambos os segmentos, proporcionou menor MMF e a massa de frutos das classes AAA e A também foi menor em relação ao sistema com fitilho. O híbrido Forty mostrou menor MFD devido ao menor MAN no sistema de condução com bambu. Não houve diferença entre os dois sistemas de condução para PTP, PCO, LAB e a massa de frutos da classe AA, para os dois segmentos de mercado. No experimento 2, não houve diferença entre os híbridos estudados nas diferentes densidades de plantio para produção e para a maioria de seus componentes, exceto para PPP, onde Forty superou Valenty, e para MFD, em que Valenty superou Forty devido a maior freqüência de LAB. O menor espaçamento entre plantas proporcionou maior NTF, PTP, NFC, PCO e massa de frutos das classes AA e A para ambos os híbridos, bem como menor MFD, PPP, MMF, massa de frutos da classe AAA e número de frutos com RAD e MAN para ambos os híbridos. O maior espaçamento entre plantas contribuiu para menor ocorrência de frutos com LAB para ambos os híbridos. / Two experiments were conducted under field conditions with the objectives of (a) determining the effect of training and staking systems of plants on yield potential and yield components of fresh market tomato hybrids of indeterminate growth habit of varietal segments Salad Extended Shelf Life (SLV) and Santa Cruz (SC) (Experiment 1), and (b) evaluating the effect of spacing between plants in the single-stem training system with polypropylene wire on yield and yield components for hybrids of segment SLV (Experiment 2). In experiment 1 it was adopted the randomized block design with the treatments in a 5 x 2 factorial scheme, and four replications, being evaluated three SLV hybrids and two SC hybrids in two systems of plant training. In experiment 2, the experimental design used was also randomized blocks with the treatments in a 2 x 4 factorial scheme, and four replications, being evaluated two SLV hybrids. The experiments were conducted in Itatiba, SP, from July 2007 to January 2008, and from January to July 2009. All plants of each plot were considered and the total number of fruits (NTF), the total production per plot (PTP), the mass of discarded fruits (MFD), the number of commercial fruits (NFC), the commercial production (PCO), the production per plant (PPP), the average mass of fruits (MMF) and the marketable fruit mass of classes AAA, AA and A, for both segments were evaluated, as well as the number of fruits with radial cracking (RAD), concentric cracking (CON), open locules with exposed seed (LAB), blotchy appearance (MAN), puffiness (OCO), and deformed (DEF). It was found that, the training system with one plant per hole, conducted with two stems staked with bamboo, provided increment of NTF, NFC and PPP, for both segments in comparison to the system of a single plant per hole with one stem trained with a propylene wire. The staking system with bamboo, for both segments, provided a smaller MMF and the mass of fruits of classes AAA and A was also lower in relation to the system with a propylene wire. The hybrid Forty showed lower MFD due to lower MAN in the staking system with bamboo. It was not found any difference between the two handling systems for PTP, PCO, LAB and for the mass of the fruits of class AA, for the two market segments. In experiment 2, there was no difference between the hybrids studied in different planting densities for production and for the majority of its components, except for PPP, in which Forty was shown to be superior than Valenty, and for MFD, in which Valenty exceeded Forty due to the greater frequency of LAB. The smaller spacing between plants provided larger NTF, PTP, NFC, PCO, and a mass of the fruits of classes AA and A for both hybrids, as well as a smaller MFD, PPP, MMF, a mass of fruits class AAA, and also a lower number of fruits with RAD and MAN for both hybrids. It was also found that, for both hybrids, under wider spacing between plants the occurrence of fruits with LAB significantly decreased.
165

Interleaved Effects in Inductive Category Learning: The Role of Memory Retention

MacKendrick, Alex 01 January 2015 (has links)
Interleaved effects are widely documented. Research demonstrates that interleaved presentation orders, as opposed to blocked orders typically benefit inductive category learning. What drives interleaved effects is less straightforward. Interleaved presentations provide both the opportunity to compare and contrast between different types of category exemplars, which are temporally juxtaposed, and the opportunity to space study of the same type of category exemplars, which are temporally separated within the presentation span. Accordingly, interleaved effects might be driven by enhanced discrimination, enhanced memory retention, or both in some measure. Though recent studies have largely endorsed enhanced discrimination as the critical mechanism driving interleaved effects, there is no strong evidence to controvert the contribution of enhanced memory retention for interleaved effects. I further examined the role of memory retention by manipulating both presentation order and category structure. Across two experiments I found that memory retention may drive interleaved effects in categorization tasks.
166

Study of the influence of interactive draw upon drawpoint spacing in block and sublevel caving mines

Halim, Adrianus January 2006 (has links)
International Caving Study 2 and Mass Mining Technology
167

Mulching, plant population density and indigenous knowledge of wild ginger (Siphonochilus Aethiopicus)

Masevhe, M.R. (Mashudu Ronnie) 12 November 2007 (has links)
Please read the abstract in the section 00front of this document / Dissertation (M Inst Agrar (Plant Production: Agronomy))--University of Pretoria, 2007. / Plant Production and Soil Science / M Inst Agrar / unrestricted
168

Improving Seed Spacing Uniformity of Precision Vegetable Planters

Siemens, M.C., Gayler, R.R. January 2016 (has links)
Equidistant, uniform seed placement is important in lettuce production as seeds are densely planted within the row, typically only about 5 cm apart. When seeds are sown too close together, it is time consuming to thin seedlings to the desired plant spacing of 20 to 30 cm by hand and very difficult to do mechanically. The overall goal of the project was to improve lettuce seed placement accuracy and reduce the percentage of seeds spaced closely together. Specific objectives were: 1) to compare vacuum and belt-type planters to determine which style of planter provides better planting performance, 2) to evaluate belt planter seeding performance with different types of furrow openers, and 3) to develop practical modifications for vacuum planters to improve lettuce seed placement accuracy. Three vacuum planter configurations, an unmodified and two reduced seed drop height designs and a belt planter equipped with two types of furrow openers were tested in situ with pelleted lettuce seed at four travel speeds ranging from 1.6 to 4.0 kph. Belt planter performance was significantly better than that of the vacuum planter. Vacuum and belt planters both provided acceptable levels of performance at speeds below 2.4 kph, but at higher speeds, seed placement accuracy declined rapidly. No differences in planter performance were found between the two belt planter configurations tested. The mid-level drop height vacuum planter configuration had significantly better seed placement precision and fewer closely spaced seed spacings as compared to the unmodified vacuum planter. These findings illustrate the significant effect planter type, travel speed, and drop height have on planter performance. They also contradict the common perception that vacuum planters deliver seed more precisely and with fewer closely-spaced seeds as compared to belt planters. Further study is needed to determine the extent to which planter performance affects hand thinning labor costs, automated machine performance, final plant stand uniformity, and crop yield.
169

Modelos matemáticos para previsão da produtividade do milho em dois sistemas de cultivo / Mathematical models for predicting the yield of corn in two cropping systems

Sasseron, Juliano Cézar 12 April 2013 (has links)
Made available in DSpace on 2016-05-02T13:53:50Z (GMT). No. of bitstreams: 1 JulianoCesarSasseronDissertacao.pdf: 912677 bytes, checksum: f2d63baed22140f9170ad66e591200ff (MD5) Previous issue date: 2013-04-12 / In order to evaluate the best crop estimation model (harvest of 10 linear meters, ear sampling, density of grains per ear) and the spacing effect between the planting line (0.50 and 0.80 m) on the productivity of maize grain (Zea mays L.) in a same environment, field experiments were conducted in the municipality of Carmo do Rio Claro, in the southern State of Minas Gerais, from August 14th, 2011 to March 6th, 2012. The outlining used was a randomized block banded with 3x2 factorial. We evaluated the estimated productivity in each model. There were differences between the estimation models, and the closest models to the actual production were obtained by harvesting 10 linear meters and by ear sampling. Also there was effect of spacing between lines, obtaining the maximum yield of grain with reduced spacing, i.e. 0.50 m. . / Com objetivo de avaliar o melhor modelo de previsão de safra (colheita de 10 metros lineares, amostragem de espiga, densidade de grãos por espiga) e o efeito do espaçamento entre linhas de plantio (0,50 e 0,80 m), sobre a produtividade de grãos de milho (Zea mays L.) em um mesmo ambiente, foram conduzidos experimentos de campo no município de Carmo do Rio Claro, no sul do estado de Minas Gerais no período de 14 de agosto de 2011 a 06 de março de 2012. O delineamento utilizado foi em blocos casualisados em faixas com fatorial 3x2. Foi avaliada a produtividade estimada em cada modelo. Houve diferença entre os métodos de previsão, sendo que os mais próximos da produção real foram obtidos através da colheita de 10 metros lineares e pela amostragem de espiga. Também houve efeito do espaçamento entre linhas, obtendo o máximo rendimento de grãos com o espaçamento reduzido, ou seja, 0,50 m.
170

FATIGUE BEHAVIOR AND SCALE EFFECTS IN RIVETED JOINTS

Abdulla, Warda Ibrahim 24 March 2021 (has links)
No description available.

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