A diallel study of American Corn Belt maize (Zea mays L.) was conducted at Holland, Virginia in 1981 and 1982. All possible crosses of twelve inbred parents (A619, A632, B73, H60, H93, H96, Mo17, Oh7B, Pa91, Val7, Va.79:419, Va85) were planted in three replications with population density treatments of 39,536, 49,420, 59,304, and 69,188 pl/ha in strips across hybrid treatments. Analyses of variance and combining ability analyses were performed on traits measuring the timing of anthesis (pollen shed) and silk emergence, on ear components of yield, and on components of kernel size. Density effects were highly significant for all traits, except for that of pollen shed duration, in the analyses combined over years. Hybrid-by-year interactions were highly significant for all traits. Correlations between GCA effects of grain yield and GCA effects of silking delay (anthesis-to-silking interval), kernels per row on the ear, ear kernel number, and kernel depth[(ear diameter - cob diameter)/2] were -0.79, 0.64, 0.66, and 0.80 in 1981, and 0.24, 0.81, 0.71, and 0.26 in 1982, respectively. Moisture stress sufficient to cause wilting occurred before and during silking in 1981. Apparently, short silking delay was associated with high moisture stress tolerance for grain yield in 1981 and was associated with long ear shoot length in 1982. Deep kernel depth apparently was associated with drought stress tolerance for yield as well. The heritabilities of ear traits were higher the earlier they became established in the sequence of development. Heritabilities of silking delay and most ear components of yield were increased by increasing planting density. However, the correlations among flowering and ear traits largely were unaffected by density, perhaps because densities were not high enough to make barrenness a substantial factor in grain yield. The most important traits related to yield were silking delay, kernels per row, kernel depth, and kernel row number. GCA to SCA variance component ratios were increased by combining data over years and by the more optimum season for yield. / Ph. D.

Yes / This study presents results from a vegetation-induced flow experimental study which investigates 3-D turbulence structure profiles, including Reynolds stress, turbulence intensity and bursting analysis of open channel flow. Different vegetation densities have been built between the adjacent vegetations, and the flow measurements are taken using acoustic Doppler velocimeter (ADV) at the locations within and downstream of the vegetation panel. Three different tests are conducted, where the first test has compact vegetations, while the second and the third tests have open spaces created by one and two empty vegetation slots within the vegetated field. Observation reveals that over 10% of eddies size is generated within the vegetated zone of compact vegetations as compared with the fewer vegetations. Significant turbulence structures variation is also observed at the points in the non-vegetated row. The findings from burst-cycle analysis show that the sweep and outward interaction events are dominant, where they further increase away from the bed. The effect of vegetation on the turbulent burst cycle is mostly obvious up to approximately two-third of vegetation height where this phenomenon is also observed for most other turbulent structure. / The full text will be available at the end of the publisher's embargo period: 1st Feb 2025

For repairing concrete transportation infrastructure, such as pavements and bridges, much importance is placed on early-age strength gain as this has a major impact on scheduling and opening to traffic. However, the long-term performance and durability of such repair materials are often not satisfactory, thus resulting in future repairs. This research project focuses on the evaluation of the durability of various rapid-setting cementitious materials. The binders studied in this project include calcium aluminate cement (CAC), calcium sulfoaluminate cement (CSA), Type III portland cement, alkali-activated fly ash (AAFA) , and various prepackaged concrete materials. In addition, selected CAC and CSA mixtures were further modified with the use of a styrene-butadiene latex. The durability aspects studied include freezing-and-thawing damage and the implications of air entrainment in these systems, alkali-silica reaction, sulfate attack, and permeability of the concrete matrix and potential corrosion. / text

The wild watermelon, Citrullus lanatus L. was among the most important foodstuffs to a number of African communities, until the colonists introduced their own foodstuffs in a process that was highly supported by the laws of the time. However, there is now a growing realization by government and other stakeholders of the importance of indigenous crops (including the wild watermelon) as substitute food stuff to improve food security. Wild watermelon is an adaptable crop, which can contribute to food security as it has a potential for commercialization. However, there are no records on the production of wild watermelon with reference to optimum planting density and the effects of mulch on the growth and development of the crop. To investigate this issue, which the smallholder farmers are faced with, a study that designed to (a) determine the effects of population density on growth and yield of wild watermelon and (b) investigate the effects of mulching on growth and yield of wild watermelon under field conditions. The study was undertaken over two seasons during which two different types of propagules, namely seed and seedlings, were used. A field study of wild watermelon establishment and yield using seeds and seedlings to compare the effects of different population densities (3000, 6000, 9000 and 12000 plants/ha) and mulching rates (0, 2.5 and 5 t/ha) based on the availability of grass on soil water, temperature, vine length (height), number of branches and leaves per plant, fruit number, total yields, fruit size and weed distribution was conducted at Dohne Agricultural Development Institute (Lat-32.52521; Long – 27.46119, alt. 907 m above sea-level) over a two year period ( 2009 – 2011 growing season). Results on data collection and analysis of growth and yield parameters are that: When seed was used as means of propagation, there were significant effects (p 0.05) of mulching and population density, on soil temperature and volumetric water content. However, no significant differences were found with regards to vine length, number of branches and leaves per plant. Concerning yield, there were no significant differences recorded on any of the measured parameters in response to mulch. Yet, with population density, significant differences were noted on fruit number per hectare and total yield at p 0.05. The number of fruits and total yield per hectare increased as plant population increased, resulting in high yields to range from 9000 -12 000 plants per hectare with both seed and seedling propagules used during the study period with or without mulching. Seedling propagules were associated with differences in soil temperature and volumetric water content with regards to mulching and population density (p 0.05). Results obtained from this study in both years, revealed that yield is more influenced by plant population density than by mulching. Mulching has been found to be ineffective as far as growth and yield are concerned, but it was found to influence soil temperature and volumetric water content. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.

Biological and social factors determines human personality. Birth order and its influence rank among strong phenotype forming factors. Practical application of the knowledge is complicated due the lack of evidence in this area in the Czech Republic. In our study, we focused on the role of age-gap between siblings and the role of gender on the birth order in education. Proportion of firstborns in various group of biology students were analysed. We found significantly higher proportions of firstborns than expected. The results were compared to the sample from the years 1990-1995. A small decrease in firstborns representation is observed. We also find big influence of gender and age-gap between siblings on the effects. Decrease in age-gaps increases the proportion of firstborns. Similar effects were found in personality traits data. Our study is unfortunately limited due to small numbers of participants. We suggest replication of our results and further testing of the effects.

The goal of Intelligent Tutoring systems (ITSs) is to engage the students in sustained reasoning activity and to interact with students based on a deep understanding of student behavior. In order to understand student behavior, ITSs rely on student modeling methods to observes student actions in the tutor and creates a quantitative representation of student knowledge, interests, affective states. Good student models are going to effectively help ITSs customize instructions, engage student's interest and then promote learning. Thus, the work of building ITSs and advancing student modeling should be considered as two interconnected components of one system rather than two separate topics. In this work, we utilized the theoretical support of a well-known learning science theory, the spacing effect, to guide the development of an ITS, called Automatic Reassessment and Relearning System (ARRS). ARRS not only validated the effectiveness of spacing effect, but it also served as a testing field which allowed us to find out new approaches to improve student learning by conducting large-scale randomized controlled trials (RCTs). The rich data set we gathered from ARRS has advanced our understanding of robust learning and helped us build student models with advanced data mining methods. At the end, we designed a set of API that supports the development of ARRS in next generation ASSISTments platform and adopted deep learning algorithms to further improve retention performance prediction. We believe our work is a successful example of combining theory and practice to advance science and address real- world problems.

Abstract Photovoltaic (PV) solar panels are solar energy collection systems with increasing terrestrial and roof applications reported worldwide. If the terrestrial mounting does not require specific wind resistance verifications, installing them on top of flat and gable roofs implies a drastic change of the roofing systems geometry, thus a re-evaluation of the wind-induced pressure is necessary. Among the roof top applications, provisions exist for the flat roofs mounted solar panels, however, design recommendations for wind-induced loadings on PV solar panels arrays flush-mounted on gable roofs are not fully developed in current wind loading standards (SEAOC PV2-2012) and building codes (ASCE 07, NBCC 2015), in spite of the numerous applications on residential and agricultural buildings, primarily due to the limited research investigating this topic. The current dissertation employs CFD k-ɛ and LE (Large Eddy) simulations for analyzing the effects of wind acting on solar panels flush-mounted on gable roofs, considering the influence of several parameters such as: the slope of the gable roof, the wind directions, the spaces between the adjacent solar panel arrays and the clearance between the roof surface and the solar panels. A comprehensive database of solar panels with different installation parameters subjected to wind speeds were developed under the current research project. The database includes detailed distribution of wind-induced pressure coefficients for the three parallel surfaces constituting the roof-solar panels systems: the top and bottom surfaces of the panels, and the roof surface under the panels, which represents a novel approach in investigating and clarifying the wind effects on solar panels. This approach also provides in detail the variation of the pressure coefficients on the three surfaces, due to the change of installation conditions (roof slope, arrays spacing, roof clearance) and wind parameters (wind speed and wind direction). As an original contribution to the existing knowledge, this thesis found that the installation of solar arrays on gable roofs, redistributes the wind-induced pressure on both sides of the roof windward and leeward, resulting in total horizontal wind-induced pressures on the entire roof lower than that registered on the corresponding roof without solar panels. In addition, dominant resultant pressure coefficients on solar panels concluded to be lower than for the roof without panels. When the roof clearance increases, total average pressure coefficients on the roof supporting the panels decreases on both, windward and leeward sides of the roof. Moreover, when the roof clearance increases, the pressures in the cavity decrease significantly on both windward and leeward sides of the roof, which could impact the requirements for installing and fixing such panels on gable roofs. For example, for 10” clearance the flush-mounted solar panels were subject to pressure instead of suction. Similarly, when panel array spacing increases, the magnitude of the net mean pressure coefficients on the roof surface under the solar panels further decreases for all wind directions investigated.

Made available in DSpace on 2017-07-25T19:29:56Z (GMT). No. of bitstreams: 1 Jhone Espindola.pdf: 1590754 bytes, checksum: 5b0837eabb44ea5516e71f7193e0ece8 (MD5) Previous issue date: 2012-09-14 / Fundação Araucária de Apoio ao Desenvolvimento Científico e Tecnológico do Paraná / The vegetables like baby leaf are characterized by the early harvest of cultivated species, and the production and marketing of these are still incipient in Brazil. To assist the production techniques, experiment was conducted between August and October 2011 with the objective of evaluating the productive responses of baby leaf chicory cv. Escarole Lisa in different environmental conditions and spacing between plants. The experimental design was a randomized complete block with 04 replications with treatments arranged in split-split. The primary factor was the growing environment (TP- low plastic tunnel; AG-white non woven; AN-natural environment), the secondary factor was spacing between plants (E1- 2 x 5 cm; E2- 4 x 5 cm; E3- 2 x 10 cm; E4- 5 x 10 cm) and tertiary factor was evaluation periods (14, 21, 28, 35 and 42 days after sowing - DAS). The characteristics evaluated were plant height (AP), leaf area index (IAF), number of leaves per plant (NF), length (CMF) and width (LMF) of the largest leaf, fresh fitomassas (FMF) and dry (FMS) and plant productivity (P). In protect cultivation, the plants reached the harvesting stage (plant height = 10 cm) at 35 days after harvest while (DAS), in the natural environment was at 41 DAS. The NF, at the point of harvest, was higher for plants grown in AN, differentiating the results for AP, CMF, LMF, FMF and IAF. FMF values in TP and AG were higher until it reaches the point of harvest. For growing baby leaf chicory, it was found that the average temperature between 18 and 19ºC was the most suitable for plant growth under protected cultivation in relation to the natural environment. The interaction between different environmental conditions and spacing between plants was significant only for FMF. For cultivation under AG, the spacing between plants E2 and E4 resulted in plants with FMF higher than the spacing between plants E1 and E3. In relation to FMF, Plants grown in AN had lower values than those under TP and AG, except for E3, where plants under GA did not differ from those of AN. For the interaction between evaluation periods and spacing between plants, there was a significant effect for FMF, FMS and IAF. It was found that the FMF and FMS in E1 and E3 were lower than E2, and E4 in 35 DAS. The results of IAF demonstrated that plants grown in smaller spacing between plants (E1) had greater leaf area expansion compared to those in lower density (E4). At harvesting stage, there was a higher productivity when the combination was used spacing between plants E1 and cultivation environment AN. It was verified that is possible to obtain precocity in the cultivation of baby leaf chicory without loss of quality in TP and AG. When all the plants reach the harvesting stage, it is possible to obtain higher productivity using the natural environment (AN) together with the spacing between plants (E1). The use of protect cultivation (non-woven and low tunnel) and spacing E1 are suitable for the cultivation and marketing of whole plant (unit sales) of baby leaf chicory instead of selling by weight. / As hortaliças tipo baby leaf são caracterizadas pela colheita precoce das folhas das espécies cultivadas, sendo que a produção e comercialização das mesmas ainda são incipientes no Brasil. Para auxiliar as técnicas de produção, foi realizado experimento entre agosto e outubro de 2011 com o objetivo de avaliar as respostas produtivas de baby leaf de chicória cv. Escarola Lisa em diferentes ambientes de cultivo e espaçamentos de plantio. O delineamento experimental foi o de blocos casualizados, com 04 repetições, com tratamentos distribuídos em parcelas sub-subdivididas. O fator primário foi ambiente de cultivo (TP- Túnel baixo com plástico; AG- Agrotêxtil branco diretamente sobre as plantas; AN- Ambiente natural); o fator secundário foi espaçamento de plantio (E1- 2 x 5 cm; E2- 4 x 5 cm; E3- 2 x 10 cm; E4- 5 x 10 cm) e o fator terciário foi momentos de avaliação (14; 21; 28; 35 e 42 dias após a semeadura - DAS). As características avaliadas foram altura de plantas (AP), índice de área foliar (IAF), número de folhas por planta (NF), comprimento (CMF) e largura (LMF) da maior folha, fitomassas fresca (FMF) e seca (FMS) das plantas e produtividade (P). Nos ambientes protegidos, as plantas atingiram o ponto de colheita (10 cm de altura) aos 35 DAS enquanto em ambiente natural foi aos 42 DAS. O NF, no ponto de colheita, foi superior para as plantas cultivadas em AN, diferenciando dos resultados encontrados para AP, CMF, LMF, FMF e IAF onde em TP e AG os valores foram superiores ao AN. Para FMS os valores em TP e AG foram superiores até atingir o ponto de colheita para baby leaf. Para o cultivo de chicória baby leaf foi constatado que a temperatura média entre 18 e 19ºC foi adequada para o maior crescimento das plantas em cultivo protegido em relação ao ambiente natural, que teve média de 16ºC. A interação entre ambiente de cultivo e espaçamentos foi significativa somente para FMF. Para o cultivo sob AG, os espaçamentos E2 e E4 resultaram em plantas com FMF superior àquelas espaçadas em E1 e E3. As plantas cultivadas em AN apresentaram menores valores de FMF que aquelas sob TP e AG, exceto para o E3 onde a FMF das plantas sob AG não diferiu daquelas do AN. Em relação à interação entre espaçamento e momentos de avaliação, verificou-se efeito significativo para FMF, FMS e IAF. Foi verificado que a FMF e FMS em E1 e E3 foram menores que em E2 e E4 a partir de 35 DAS. Os resultados de IAF demonstraram que as plantas cultivadas no menor espaçamento (E1) apresentaram maior expansão da área foliar em relação àquelas menos adensadas (E4). No ponto de colheita, houve maior produtividade quando foi utilizada a combinação entre o espaçamento E1 e cultivo em ambiente AN. Concluiu-se que é possível obter precocidade no cultivo de baby leaf de chicória sem perda de qualidade sob TP e AG. Quando todas as plantas atingem o ponto de colheita, é possível obter maior produtividade utilizando o ambiente natural (AN) juntamente com o espaçamento mais adensado (E1). O uso do cultivo protegido (Agrotêxtil e Túnel baixo) e o espaçamento E1 são adequados para o cultivo e comercialização de planta inteira (venda da unidade) de baby leaf de chicória em lugar da venda por peso produto.

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.

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