Academic literature on the topic 'Full tree system'
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Journal articles on the topic "Full tree system"
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MacDonell, Marc R., and Arthur Groot. "Harvesting peatland black spruce: Impacts on advance growth and site disturbance." Forestry Chronicle 73, no. 2 (April 1, 1997): 249–55. http://dx.doi.org/10.5558/tfc73249-2.
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A project was established in the Lake Abitibi Model Forest to study the effects of several harvesting systems on advance growth protection and site disturbance. Tree-length and cut-to-length harvesting systems were compared to a full-tree system on peatland black spruce (Picea mariana (Mill.) B.S.P.) sites. The impacts of the various harvesting systems were compared by summarizing the structural and mensurational properties of the stands before and after harvest, by evaluating damage to residual trees, and by assessing site disturbance. The tree-length and full-tree systems, which were compared in winter harvesting, produced similar results. The cut-to-length system was compared to the full-tree system in both winter and summer harvesting, and protected substantially more advance growth, especially in the summer. Additionally, the cut-to-length system produced less damage to residual trees and lesser amounts of site disturbance. All harvesting systems resulted in or maintained residual stands with an uneven-size structure. Key words: black spruce, advanced regweneration, tree harvesting, systems
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Fallahi*, Esmaeil. "Effects of Various Irrigation Regimes on Tree Growth, Water Use, and Mineral Nutrients of `Fuji' and `Gala' Apples." HortScience 39, no. 4 (July 2004): 842A—842. http://dx.doi.org/10.21273/hortsci.39.4.842a.
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Effects of seven different irrigation systems for `Fuji' and two irrigation systems for `Gala' on five rootstocks on tree growth, water use, and mineral nutrients were studied. All forms of drip system used significanly less water than sprinkler systems. Patial root drying sprinkler system used 50% less water than full sprinkler. Application of partial root drying drip at 50% rate of full drip was not sufficient and trees had to receive 75% of full drip to survive. Trees under full sprinkler used about 28 inches of water while those with drip used less than 8 inches of water during the 2003 growing season. Leaf minerals, particularly N and K were affected by irrigation systems. Trees with buried drip required less water than those with above-ground drip system. Calculation of water requirement on a tree-use basis provided an excellent guide for irrigation.
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WILSON, T. D., R. M. BROOK, and H. F. TOMLINSON. "INTERACTIONS BETWEEN NÉRÉ (PARKIA BIGLOBOSA) AND UNDER-PLANTED SORGHUM IN A PARKLAND SYSTEM IN BURKINA FASO." Experimental Agriculture 34, no. 1 (January 1998): 85–99. http://dx.doi.org/10.1017/s0014479798001069.
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A farmer's intercropping system of white sorghum (Sorghum bicolor) and néré (Parkia biglobosa) was studied in Burkina Faso. In quadrats in three differing zones of tree influence, full sun (open field), semi-shade (under the edge of the tree crown) and full shade (under the crown), tree morphology and associated sorghum growth were recorded together with micro-meterological parameters. Mean photosynthetic photon flux density (PFD) was reduced to 51 and 26% of full sun levels, in the semi-shaded and fully shaded quadrats respectively. Soil temperature and moisture were also recorded. In the season studied, the principal effect of the trees on the crop was competition for light. For plants in full shade, total shoot and panicle mass were halved compared with the crop in full sun. However, plants in semi-shade were able to compensate for decreased PFD almost entirely. Measurable compensatory effects were decreased rate of leaf senescence, greater partitioning of resources into leaf production, and larger, thinner leaf laminae. It was concluded that the current farmers' practice of sowing under the crowns of trees produced a worthwhile, if somewhat reduced, crop yield, and that socially, economically and ecologically the sorghum–néré parkland system was worth retaining.
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Fallahi, Esmaeil, James R. McFerson, and Bahar Fallahi. "Irrigation and Rootstocks Affect Water Use, Growth, Nutrition, Yield, and Fruit Quality of `Fuji' and `Gala' Apples." HortScience 41, no. 4 (July 2006): 982C—982. http://dx.doi.org/10.21273/hortsci.41.4.982c.
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Many fruit growers in the Pacific Northwest region prefer to use a sprinkler system to produce high-quality fruit and to establish a cover crop in the orchard. However, water shortage mandates the use of more efficient methods of irrigation, such as drip. In this long-term experiment, the effects of seven irrigation systems for `Fuji' and two irrigation systems for `Gala' on five rootstocks on tree growth, water use, fruit quality, and mineral nutrients were studied. All forms of drip systems used less water than full micro-sprinkler (SP). Partial root drying sprinkler (PS) used 50% less water than SP. Trees with partial root drying drip and deficit drip had to receive 65% of full drip to survive. Each `Fuji' tree with SP used about 5397 L of water in 2004 and 5833 L in 2005, while each tree with full drip used 2403 L in 2004 and 3438 L in 2005. Thus, trees with full drip used 41% to 55% less water than those with SP system without any reduction in fruit quality. This leads to a major savings in the cost of fruit production. Fruit weight in trees with full drip was always greater than those with PS or deficit drip. Fruits with SP system had lower soluble solids than those with PS. Fruits from trees with partial drip had a higher starch degradation than those with other systems. Leaf minerals, particularly N and K, were affected by irrigation systems. `Pacific Gala' trees on B.9 rootstock were more precocious than those on Supporter-4 rootstock. In general, `Pacific Gala' on RN-29 had better tree performance and fruit quality than those on other rootstocks. The calculation of water requirements on a tree-use basis provided an excellent guide for drip irrigation.
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Fallahi, Esmaeil, Bahar Fallahi, and Bahman Shafii. "Irrigation and Rootstock Influence on Water Use, Tree Growth, Yield, and Fruit Quality at Harvest at Different Ages of Trees in ‘Pacific Gala’ Apple." HortScience 48, no. 5 (May 2013): 588–93. http://dx.doi.org/10.21273/hortsci.48.5.588.
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During various ages of tree between 2002 and 2007, the effects of four rootstocks and two irrigation systems using a crop evapotranspiration-based (ETc) water scheduling on water use, tree growth, yield, and fruit quality at harvest in ‘Pacific Gala’ apple [(Malus ×domestica) Borkh] were studied. The use of ETc when a precise crop coefficient value (Kc), modified by percentage of ground shade (GS) and tree canopy maturity (M) was used, provided a reliable tool for irrigation scheduling of ‘Pacific Gala’ apple. Young trees with a full sprinkler (FS) system received an average of 872.3 mm (5616.8 L/tree), whereas those with full drip (FD) received 448.9 mm (2921.1 L/tree). However, when trees were mature, trees with a FS system received an average of 994 mm (6461.7 L/tree), whereas trees with a FD received 614.1 mm (3996 L/tree) of irrigation water per growing season. Trees on ‘Budagovsky 9’ (‘B.9’) had smaller trunk cross-sectional area (TCA) and higher yield efficiency, whereas those on ‘Supporter4’ (‘Sup.4’) had larger TCA and lower yield efficiency than those on other rootstocks in all years of the study. Trees on ‘Nic.9’ (‘RN29’) always had higher yield per tree as compared with those on other rootstocks. Trees on ‘RN29’ often had higher but trees on ‘B.9’ had lower fruit weight than did those on other rootstocks. Trees on ‘Sup.4’, despite their lower yields, had smaller fruits than those on ‘RN29’ every year and thus were not suitable for planting. Fruit from trees on ‘B.9’ and ‘Cornell-Geneva30’ (‘G.30’) often had higher soluble solids concentration (SSC) and starch degradation pattern (SDP) than those other rootstocks. Fruits from trees on ‘G.30’ also had lower firmness and higher stem-end cracking, suggesting that this rootstock advances maturity in ‘Pacific Gala’ apple. Trees with FS irrigation had higher TCA than those with the FD system. Trees with the FD system were more precocious and had higher yield per tree, yield efficiency, and fruit weight than trees with the FS system when they were young. However, these differences were not significant when trees matured. ‘Pacific Gala’ fruit from trees with FS consistently had better color than those with the FD system every year. Fruits from young trees with the FD system often had higher SDP and lower firmness than those from FS irrigation.
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Fallahi, Esmaeil, Bahar Fallahi, and Michael J. Kiester. "Evapotranspiration-based Irrigation Systems and Nitrogen Effects on Yield and Fruit Quality at Harvest in Fully Mature ‘Fuji’ Apple Trees over Four Years." HortScience 53, no. 1 (January 2018): 38–43. http://dx.doi.org/10.21273/hortsci12393-17.
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In a long-term study between 2008 and 2011, the use of crop evapotranspiration (ETc), when a precise crop coefficient value (Kc) was used, provided a reliable irrigation scheduling for determination of water requirement for ‘Autumn Rose Fuji’ apple (Malus ×domestica Borkh) fully mature trees. Water use, yield, and fruit quality attributes at harvest were examined under various irrigation and nitrogen (N) systems that were scheduled using ETc. Trees with a full sprinkler (FS) system received ≈39% to 41% more water than those with a full drip (FD) system during the period of 2008–11 growing seasons. On average, mature trees with an FS system received 5927.6 L (944 mm), whereas those with an FD system received 3610.3 L of water per tree (554.9 mm) per growing season over the period of 2008 through 2011. Fruit from trees with FS and FD were larger, whereas those with 50% FS were smaller than those from all other treatments. Trees with 50% FS treatment received a higher volume of water but had smaller fruit size than those with 50% FD or 65% FD. Averaging values over 4 years revealed that applications of any form of deficit irrigation (DI), either by microjet irrigation or drip, increased fruit soluble solids concentration (SSC) and firmness but decreased water core at harvest. Considering yield, and quality attributes in this study, a well-calculated ETc-based FD irrigation system is recommended over any other irrigation regime. If application of deficit water is mandated, application of 65% FD is preferred over 50% FS, as trees with 65% FD treatment received less water while had larger fruit than those of 50% FS. Trees receiving 80 g N/tree had lower fruit color and russet than those receiving 40 g N/tree. However, other yield and quality attributes were unaffected by the rate of N fertigation.
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Letunic, Ivica, and Peer Bork. "Interactive Tree Of Life (iTOL) v4: recent updates and new developments." Nucleic Acids Research 47, W1 (April 1, 2019): W256—W259. http://dx.doi.org/10.1093/nar/gkz239.
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Abstract The Interactive Tree Of Life (https://itol.embl.de) is an online tool for the display, manipulation and annotation of phylogenetic and other trees. It is freely available and open to everyone. The current version introduces four new dataset types, together with numerous new features. Annotation options have been expanded and new control options added for many display elements. An interactive spreadsheet-like editor has been implemented, providing dataset creation and editing directly in the web interface. Font support has been rewritten with full support for UTF-8 character encoding throughout the user interface. Google Web Fonts are now fully supported in the tree text labels. iTOL v4 is the first tool which supports direct visualization of Qiime 2 trees and associated annotations. The user account system has been streamlined and expanded with new navigation options, and currently handles >700 000 trees from more than 40 000 individual users. Full batch access has been implemented allowing programmatic upload and export of trees and annotations.
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Violino, Simona, Federico Pallottino, Giulio Sperandio, Simone Figorilli, Luciano Ortenzi, Francesco Tocci, Simone Vasta, Giancarlo Imperi, and Corrado Costa. "A Full Technological Traceability System for Extra Virgin Olive Oil." Foods 9, no. 5 (May 13, 2020): 624. http://dx.doi.org/10.3390/foods9050624.
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The traceability of extra virgin olive oil (EVOO) could guarantee the authenticity of the product and the protection of the consumer if it is part of a system able to certify the traceability information. The purpose of this paper was to propose and apply a complete electronic traceability prototype along the entire EVOO production chain of a small Italian farm and to verify its economic sustainability. The full traceability of the EVOO extracted from 33 olive trees from three different cultivars (Carboncella, Frantoio and Leccino) was considered. The technological traceability system (TTS; infotracing) consists of several open source devices (based on radio frequency identification (RFID) and QR code technologies) able to track the EVOO from the standing olive tree to the final consumer. The infotracing system was composed of a dedicated open source app and was designed for easy blockchain integration. In addition, an economic analysis of the proposed TTS, with reference to the semi-mechanized olive harvesting process, was conducted. The results showed that the incidence of the TTS application on the whole production varies between 3% and 15.5%, (production from 5 to 60 kg tree−1). The application at the consortium level with mechanized harvesting is fully sustainable in economic terms. The proposed TTS could not only provide guarantees to the final consumer but could also direct the farmer towards precision farming management.
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Domingues, Miguel Sales, Cristiana Andrighetto, Gelci Carlos Lupatini, Gustavo Pavan Mateus, Aline Sampaio Aranha, Rafael Keith Ono, Mayara Mayumi dos Santos Shiguematsu, Polyana Vellone Giacomini, and Bianca Midori Souza Sekiya. "Growth and yield of corn forage intercropped with marandu grass in an agrosilvopastoral system with eucalyptus." Semina: Ciências Agrárias 38, no. 6 (November 23, 2017): 3669. http://dx.doi.org/10.5433/1679-0359.2017v38n6p3669.
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Corn and grass intercropping is an interesting practice, and forage plants belonging to the genus Urochloa are the most commonly used in these situations. These plants show excellent adaptation to low-fertility soil, easy establishment, considerable biomass production, as well as being an important competitor with weeds. In agrosilvopastoral systems, the yield of corn crops grown together with trees is hindered due to the reduced radiation incidence caused by tree shading. This study aimed to evaluate corn growth, light interception, and chlorophyll content when intercropped with marandu grass in an agrosilvopastoral system with one and three eucalyptus rows, and compare them with plants under full sun. The experiment was conducted in Andradina - SP (Brazil). Treatments consisted of intercropping with no eucalyptus (plants under full sun: control), one system with one eucalyptus row and another with three rows. We also assessed the effect of five distances between corn plants and eucalyptus trees (2, 4, 6, 8, and 10 m). Between eucalyptus rows, corn plants were intercropped with marandu grass. The analyzed variables were corn plant height, ear height, chlorophyll content index, light interception, dry matter, and fresh and dry forage weights. The experimental design was a randomized block in a factorial scheme plus a control, with four repetitions. Tree arrangements had no influence on corn forage, dry matter, plant height, or ear height. Lower results of yield, dry matter, plant height, and ear height were observed for plants spaced 2 m from trees. In the first two evaluations, significant differences of light interception were found for the different distances. Neither tree arrangements (one and three rows) nor the distances from the trees had any impact on corn heights, with no difference between control and the agrosilvopastoral systems. Neither plant distances from trees nor tree arrangements had an influence on chlorophyll content index of corn plants, with no difference between control and the treatments. As a result, corn growth and forage yield under agroforestry systems are similar in arrangements of 1 and 3 eucalyptus rows (15-month-old trees) and under full sun. However, corn dry matter contents were lower in systems containing trees. Intercropping corn and marandu grass in a system without trees increased light interception at harvest time, indicating a larger soil coverage. Corn forage yield and dry matter content were lower when plants were 2 m apart from eucalyptus trees since this condition provided a lower amount of light and greater competition for water and nutrients.
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Fallahi, Esmaeil, Denise Neilsen, Gerry H. Neilsen, Bahar Fallahi, and Bahman Shafii. "Efficient Irrigation for Optimum Fruit Quality and Yield in Apples." HortScience 45, no. 11 (November 2010): 1616–25. http://dx.doi.org/10.21273/hortsci.45.11.1616.
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Use of crop evapotranspiration (ETc), when a precise crop coefficient value (Kc) is used, provides a reliable tool (irrigation scheduling) for determination of water requirement. In this process, Kc should be modified by percentage of ground shade (GS) and tree canopy maturity (M). In an experiment in Idaho with ET-based irrigation scheduling, each tree with a full microjet sprinkler system received an average of 6461.7 L (994 mm), whereas each one with a full drip system used 3996 L (614.1 mm) of irrigation water. In general, deficit drip irrigation was shown to initially increase yield as a result of induction of stress and the production of a higher number of fruit spurs. However, production declined if the extreme water deficiency was repeatedly applied to the trees over several years. Using a microjet sprinkler system, a partial root zone drying regime reduced fruit size but slightly improved fruit color. Application of water at 65% full drip rate, applied on both sides of the tree row (DD), reduced fruit size. However, when the 65% of full drip rate was applied to only one of the alternating sides of the tree every other week (PRD), fruit size was larger than those with DD treatment.
Dissertations / Theses on the topic "Full tree system"
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Bosi, Cristiam. "Parameterization and evaluation of mechanistic crop models for estimating Urochloa brizantha cv. BRS Piatã productivity under full sun and in silvopastoral system." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11152/tde-15052018-142008/.
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Silvopastoral systems are a kind of agroforestry system in which trees or shrubs are combined with animals and pastures. Silvopastoral systems are important to intensify pasture production and mitigate climate change effects. However, very few studies have been performed to adapt crop models to simulate these systems. The aim of this study was to parameterize and test the mechanistic crop models APSIM and CROPGRO for estimating Urochloa brizantha cv. BRS Piatã productivity under full sun and in a silvopastoral system, to evaluate the models\' performance to simulate tree-crop interactions, and to develop tools to improve these simulations. For this purpose, four field experiments were conducted under full sun to investigate cutting management under irrigated and rainfed conditions and grazing management under rainfed conditions with high and low N supply. Another experiment was carried out in a silvopastoral system with the trees arranged in simple rows, in East-West orientation, with 15 m between rows and 2 m between plants in the rows. This experiment was conducted under grazing management and rainfed conditions with the pasture variables, microclimate and soil water content being assessed at four distances from the North row (0.00 m, 3.75 m, 7.50 m and 11.25 m). The forage mass simulations for the pasture at full sun, performed using the APSIM-Tropical Pasture model, showed good agreement between observed and estimated data (R2 between 0.82 and 0.97, d between 0.92 and 0.98, and NSE ranging from 0.72 to 0.92), while the simulations with the CROPGRO-Perennial Forage model achieved good precision (R2 between 0.65 and 0.93) and good accuracy (d from 0.86 to 0.97, and NSE from 0.60 to 0.90), for the various managements and environmental conditions. Even considering the promising performance of both models for pastures under full sun, they already needs to be tested in other locations, climate conditions, soils, and grazing or cutting intensities, to prove its accuracy and reach enough confidence. The pasture growth simulations at the silvopastoral system indicated that the APSIM-Tropical Pasture was efficient when only competition by solar radiation was considered (R2 from 0.69 to 0.88, d from 0.90 to 0.96, and NSE between 0.51 and 0.85), but inefficient when considering only competition by soil water (R2 between 0.58 and 0.85, d between 0.58 and 0.82, and NSE from -4.07 to -0.14). The CROPGRO-Perennial Forage achieved good performance on pasture growth simulation at the distances 0.00 m, 3.75 m, and 7.50 m from the trees (R2 from 0.75 to 0.90, d from 0.93 to 0.96, NSE between 0.74 and 0.85). Despite the good results, improvements should be performed in both models for simulating all factors that affect forage growth in silvopastoral systems.Os sistemas silvipastoris são um tipo de sistema agroflorestal em que árvores ou arbustos são combinados com animais e pastagens. Os sistemas silvipastoris são importantes para a intensificação de pastagens e para a mitigação dos efeitos das mudanças climáticas. Entretanto, poucos estudos vêm sendo realizados visando à adaptação de modelos para a simulação desses sistemas. O objetivo desse estudo foi parametrizar e testar os modelos mecanísticos APSIM e CROPGRO para estimar a produtividade de Urochloa brizantha cv. BRS Piatã a pleno sol e em um sistema silvipastoril, avaliar o desempenho dos modelos para simular as interações árvore-pastagem e desenvolver ferramentas para aprimorar tais simulações. Para isso, foram conduzidos quatro experimentos de campo, a pleno sol, para avaliar diferentes manejos da pastagem: corte, em irrigado e sequeiro; e pastejo, em sequeiro e com alto ou baixo suprimento de nitrogênio. Outro experimento foi conduzido em um sistema silvipastoril com as árvores arranjadas em renques simples, com orientação Leste-Oeste, com espaçamento de 15 m entre renques e 2 m entre plantas nos renques. Esse experimento foi conduzido sob pastejo e em sequeiro, com avaliações das variáveis da pastagem, microclima e água no solo em quatro distâncias em relação ao renque Norte (0,00 m; 3,75 m; 7,50 m and 11,25 m). As estimativas de massa de forragem a pleno sol, realizadas com o modelo APSIM-Tropical Pasture, apresentaram boa concordância entre os dados observados e os estimados (R2 entre 0,82 e 0,97, d entre 0,92 e 0,98 e NSE de 0,72 a 0,92), enquanto que, as estimativas geradas pelo modelo CROPGRO-Perennial Forage alcançaram boa precisão (R2 entre 0,65 e 0,93) e boa exatidão (d entre 0,86 e 0,97 e NSE de 0,60 a 0,90), para os diferentes manejos e condições ambientais. Mesmo considerando o desempenho promissor de ambos os modelos para simular pastagens a pleno sol, para confirmar a acurácia e a eficiência destes, são necessários testes em outros locais, condições climáticas, tipos de solo e intensidades de corte ou pastejo. As simulações do crescimento da pastagem no sistema silvipastoril indicaram que o modelo APSIM-Tropical Pasture, foi eficiente quando somente a competição por radiação solar foi considerada (R2 de 0,69 a 0,88, d entre 0,90 e 0,96 e NSE de 0,51 a 0,85), mas ineficiente quando somente a competição por água no solo foi considerada (R2 entre 0,58 e 0,85, d entre 0,58 e 0,82 e NSE de -4,07 a -0,14). O modelo CROPGRO-Perennial Forage atingiu bom desempenho na simulação do crescimento da pastagem para as distâncias 0,00 m, 3,75 m e 7,50 m em relação às árvores (R2 de 0,75 a 0,90, d entre 0,93 e 0,96, NSE de 0,74 a 0,85). Apesar dos bons resultados, ambos os modelos devem ser melhorados para simular todos os fatores que afetam o crescimento de pastagens em sistemas silvipastoris.
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Salmins, Sandra S. (Sandra Sylvia). "Apple tree growth and yield in alternative ground management systems." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68256.
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Dwarf apple tree growth and yield under several non-herbicidal ground management systems were compared. Six ground cover systems were established in two newly planted orchards. After two growing seasons, trees in the straw mulch and geotextile mulch treatments had larger trunk cross-sectional areas and more shoot growth than trees in the red fescue and insectary plant cover treatments. Growth of trees under the manure mulch and cultivation treatments was intermediate. When four of the systems were established along rows of five-year old trees in an existing orchard, the increase in trunk cross-sectional area over two growing seasons was greatest for trees in the manure mulch and straw mulch followed by tose in geotextile mulch, trees in the red fescue grew least. The use of a mulch, such as straw or geotextile, has a favourable effect on growth and has potential for use in organic orchards.
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Min, Byung No. "Object-oriented modeling for the dynamics of tree-topological flexible multibody systems." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19569.
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Obtaining equations of motion is quite demanding but indispensable for the simulation of a multibody system, especially in space applications. This thesis is devoted to establishing a dynamics formalism and modeling tool in the framework of the objectoriented method for flexible multibody systems in a tree topology. In order to manage the modular construct as well as to take the material flexibility of body into account, the formulations are based on the Euler-Lagrange method in conjunction with the natural orthogonal complement of the kinematic constraint matrix. The elements constituting the dynamics of multibody mechanical systems are identified under the standard mathematical formats. They are embodied into distinct object modules equipped with characteristic variables and operations. A general flexible body is decomposed into several components with the kinematics and kinetics objects, while various types of articulation are delimited as the joint objects. The free-floating condition is represented by a special joint object having six degrees of freedom. A dynamics model is achieved by the interconnection of the object modules according to the relationships for data flow. A recursion formula, in conjunction with the lower body index representation, systematically evaluates the natural orthogonal complement matrix, which leads to a minimal set of equations of motion. The proposed method has been implemented to yield a practical modeling tool. It is validated through various simulation cases. The results match with the solutions of explicit formulations as well as the outputs from a sophisticated functional simulation facility. Additional simulations are performed with the incorporation of a control scheme.
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Kuhn, Roland. "Keyword classification trees for speech understanding systems." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41238.
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Speech understanding systems try to extract meaning from one or several word sequences hypotheses generated by a speech recognizer. Designers of these systems rely increasingly on robust matchers to perform this task; a robust matcher processes semantically important word islands rather than attempting to parse the entire word sequence. This thesis describes a robust matcher for speech understanding whose rules are learned automatically from training data. Learning is carried out by a new set of algorithms involving a new data structure, the Keyword Classification Tree (KCT). By eliminating the need to handcode and debug a large number of rules, this approach facilitates rapid construction of a speech understanding system. Furthermore, the rules learned by a KCT, which depend on a very small number of words in each utterance, are highly resistant to errors by the speaker or by the speech recognizer. The thesis discusses a speech understanding system built at the Centre de Recherche Informatique de Montreal that incorporates this robust matcher, using the DARPA-sponsored Air Travel Information System (ATIS) task as training corpus and testbed.
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Bambrick, Amanda. "Soil organic carbon in tree-based intercropping systems of Quebec and Ontario, Canada." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40848.
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ABSTRACT M.Sc.Amanda D. BambrickNatural Resource Sciences Tree-based intercropping (TBI) is an agroforestry system where a crop, generally an annual, is planted between established tree rows. TBI systems have a greater potential for carbon storage than conventional cropping systems because carbon is stored in the biomass of growing trees and trees provide additional carbon inputs (leaves, roots) that contribute to the soil organic carbon (SOC) pool. Differences in the litter quality and amount of litter deposited in the tree row versus the intercropped space are expected to generate spatial heterogeneity in the SOC pool. The objectives of this work were to evaluate the spatial variability of the SOC pool in TBI systems, to compare SOC stocks in the TBI system with a nearby conventional agroecosystem, and to describe the SOC dynamics in a TBI system using the ecosys model. Research sites included in this study were 4-year old TBI sites at St. Paulin and St. Edouard (Quebec, Canada), an 8-year old TBI site in St. Remi, Quebec, and a 21 year old TBI site in Guelph, Ontario, Canada. Spatial heterogeneity in SOC pools due to the presence of trees was observed in two of the four sites, but obscured by field variability at one site and even distribution of leaf litter associated with large trees at the oldest TBI site. The SOC pool increased in older TBI sites, relative to the nearby conventional agroecosystem, but the magnitude of SOC change was affected by the land use history. A simulation of changes in SOC using the ecosys environmental model predicted a 5.0% decrease in SOC pools twenty-one years after the site was converted to TBI, while field experiments showed a 12% increase in the SOC pool compared to the conventional agroecosystem. A spatial algorithm that describes the distribution of trees and crops in TBI systems would improve ecosys model predictions. Overall, field results suggest that the trees growing in TBI systems will increase SOC levels after a nRESUMÉM.Sc.Amanda D. BambrickSciences de ResourcesNaturellesUn système de culture intercalaire (SCI) est un système d’agrosylviculture où une récolte, généralement annuelle, est établie entre les rangées d'arbres plantées. Le SCI a un potentiel important pour être adoptés dans les régions tempérées dû aux avantages environnementaux liés à ces systèmes. Un tel avantage environnemental fourni par SCI est le stockage accru de carbone dans les sols et la biomasse des plantes. Le SCI a un potentiel important pour le stockage de carbone (C) car il contienne de carbone dans la biomasse des arbres croissants, et l’ajout au sol des résides d’arbres (feuilles, racines) contribuent au C organique du sol (SOC). On s'attend à ce que des différences dans la qualité et la quantité des résides organiques déposées dans la rangée d'arbre contre l'espace intercalaire produisent de l'hétérogénéité spatiale de SOC. Les objectifs de cette thèse étaient i) d'évaluer la variabilité spatiale de SOC dans le SCI, ii) comparer des stocks de SOC dans le SCI à un agro-écosystème conventionnel, et iii) décrire la dynamique de SOC dans le SCI utilisant le model ecosys. Les sites expérimentaux incluant dans cette étude étaient des emplacements de quatre ans à St. Paulin et St. Édouard (Québec, Canada), de huit ans à St. Rémi, Québec et de 21 ans à Guelph (Ontario, Canada). L'hétérogénéité spatiale au SOC due à la présence des arbres a été observée dans deux des quatre sites, mais obscurcie par la variabilité de terrain a un site et par la distribution égale de feuillage liée à de grands arbres à l'emplacement de SCI le plus ancien. Le stock de SOC accrue dans des sites de SCI le plus anciens, relativement à l'agro-écosystème conventionnel, mais l'importance de changement de SOC a été affectée par l'histoire d'utilisation de la terre. Une simulation des changements du SOC utilisant le modèle ecosys a prévu une diminut
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Oyarce, Guillermo Alfredo. "A Study of Graphically Chosen Features for Representation of TREC Topic-Document Sets." Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2456/.
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Document representation is important for computer-based text processing. Good document representations must include at least the most salient concepts of the document. Documents exist in a multidimensional space that difficult the identification of what concepts to include. A current problem is to measure the effectiveness of the different strategies that have been proposed to accomplish this task. As a contribution towards this goal, this dissertation studied the visual inter-document relationship in a dimensionally reduced space.
The same treatment was done on full text and on three document representations. Two of the representations were based on the assumption that the salient features in a document set follow the chi-distribution in the whole document set. The third document representation identified features through a novel method. A Coefficient of Variability was calculated by normalizing the Cartesian distance of the discriminating value in the relevant and the non-relevant document subsets. Also, the local dictionary method was used. Cosine similarity values measured the inter-document distance in the information space and formed a matrix to serve as input to the Multi-Dimensional Scale (MDS) procedure. A Precision-Recall procedure was averaged across all treatments to statistically compare them. Treatments were not found to be statistically the same and the null hypotheses were rejected.
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Walsh, Brice D. (Brice David). "Mulch management systems in organic dwarf apple orchards and their effects on soil physical properties, soil nutrient availability, and tree nutrition." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=55402.
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An alternative to herbicides in dwarf apple orchards (Malus pumila Mill.) is the use of mulches. Research objectives were to compare several mulch systems (Festuca rubra L., Lupinus albus L. plus Daucus carota L.; straw, manure compost, geotextile) with soil cultivation as to soil physical properties and plant nutrient levels in soils, leaves and fruit. Studies carried out in 1992 and 1993 on three dwarf apple orchards on the Macdonald Campus of McGill University showed that straw mulch increased soil water contents and exchangeable K, but reduced exchangeable Mg compared to Festuca mulch. Straw mulch reduced soil temperatures in summer relative to geotextile or cultivation. Festuca reduced leaf N contents but increased leaf P contents-elative to geotextile treatments. Soil nitrate N contents were correlated with soil water contents, and the ratios N/Ca and K/Ca in the fruit were unaffected by treatment. Straw and geotextile mulches increased soil water content and nitrate-N levels during peak sowing periods and thus were the superior treatments.
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Rampazzo, Fabiano Pinheiro. "Estudo de viabilidade do sistema de ancoragem de uma unidade flutuante de produção e armazenamento \"FPSO\" acoplada a um sistema de completação seca \"TLWP\"." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/3/3135/tde-13072011-103539/.
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A produção de petróleo e gás em campos brasileiros é cada vez mais proveniente de regiões com águas profundas e situadas longe da costa, chegando a distâncias de mais de 100 km, como, por exemplo, na Bacia de Campos ou de Santos. Devido à falta de infra-estrutura e às características do petróleo desses campos, a cadeia de abastecimento e o sistema de exportação da produção possuem grande importância para a indústria offshore. Uma maneira usual para a exportação da produção é através de dutos submarinos, onde o óleo e/ou a gás flui das plataformas diretamente para o continente. Com esta infra-estrutura é possível a utilização de sistemas de produção sem capacidade de armazenamento e, conseqüentemente, torna-se desnecessário o uso de navios para o alívio da produção. No entanto, devido à qualidade do óleo e às distâncias entre os poços e a costa em alguns campos brasileiros, a utilização dos oleodutos mostra-se uma solução pouco viável. Por este motivo, é bastante comum o uso de FPSOs ou semi-submersíveis conectadas a sistemas auxiliares, como o FSO (Floating Storage and Offloading). Nas plataformas, outra característica importante e desejada é tornar viável o uso de um sistema de completação seca (árvore de Natal acima da linha dágua) com o objetivo de diminuir, significativamente, os custos operacionais envolvidos. Esse tipo de completação é utilizado, com excelência, por unidade do tipo TLWP ou Spar, devido ao baixo nível dos movimentos e acelerações observadas nestas plataformas. Entretanto, as condições ambientais severas amplificam as dificuldades para encontrar um sistema com grande capacidade de armazenamento e que permita o uso de completação seca. Neste contexto, pesquisadores e engenheiros estão sendo obrigados a desenvolver novos conceitos capazes de atender a essa demanda. Desta forma, uma nova solução, considerando um FPSO e uma TLWP operando a uma curta distância e trabalhando de forma acoplada com a conexão garantida por cabos sintéticos vem sendo estudada. Essencialmente, o grande atrativo deste conceito é o fato de que toda a produção e o armazenamento são concentrados no FPSO e a TLWP é responsável pela perfuração e extração dos hidrocarbonetos através de risers verticais. Assim o sistema trabalhando de forma conjunta possui capacidade de armazenamento e permite o uso da completação seca. Nesta dissertação, foi realizado um estudo sobre a evolução deste novo conceito, dividido em três fases. A primeira focada no dimensionamento do sistema de conexão e ancoragem das unidades e em uma investigação da interação hidrodinâmica entre as unidades de forma a mostrar a viabilidade do sistema. A segunda fase, focada na validação dos resultados por meio da comparação com os testes realizados no modelo em escala do NMRI (National Maritime Research Institute - Japão). Finalmente, a terceira fase, com foco no redimensionamento do sistema de amarração e no sistema de conexão, com base nos resultados obtidos na segunda fase.The oil and gas production in Brazilian fields are commonly found in deep water and situated far away from the coast, reaching distances of more than 100 km as, for example, in the Campos Basin or Santos Basin. Due to the heavy oil and lack of pipeline infrastructure found in these fields, not only subsea equipments that must support high pressure but also logistics problems such as supply chain and production exportation system play an important role for the offshore industry. A usual way to export the production is to concentrate it in hubs of submarine pipelines which flows the oil or gas from the platforms to the continent. This infrastructure makes possible the use of no storage production systems and, consequently, releases the use of the shuttle tanks employment. However, due to the quality of the oil and the distances between the wells and the coast, some Brazilian fields do not allow the use of the pipelines to export their production. For this reason, is quite common to use FPSO and semi-submersible aided by auxiliary systems such as the FSO (Floating Storage and Offloading) units. Another important and desired characteristic of production platforms is to make it feasible to install a dry Christmas tree system aiming to decrease, significantly, operational costs involved. This feature is performed, with excellence, by TLWP and Spar units due to the low level of motions and accelerations observed in these platforms. Harsh environmental conditions can bring difficulties to find a solution of a system with both storage and dry tree system capability. In this context, researchers and engineers are being forced to develop new technological systems capable to support this demand. In this way, a new solution considering a FPSO and a TLWP coupled in a short distance by synthetic ropes has being studied. Essentially, the attractive feature of this concept is the fact that the production is performed by the FPSO whereas the TLWP is responsible to support the risers and drilling facilities turning the system coupled, equipped with a dry Christmas tree and with the possibility to storage the production. By now, the concept evolution has been divided in three phases. The first phase concerned about an advanced research focusing on the connection and mooring system development and the hydrodynamic interaction between the units and having in mind the verification of the concept feasibility. The second phase, concerned about the results validation by a comparison with scale model tests performed in the NMRI (National Maritime Research Institute Japan). Finally, the third phase, has the focus in the mooring and connection system resizing based on the results obtained on second phase.
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GALIPO', GIOVANNI. "Interventi di utilizzazione forestale nella Riserva Naturale Biogenetica di Vallombrosa: indagine sul recupero integrale di biomasse." Doctoral thesis, 2012. http://hdl.handle.net/2158/799455.
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Dalla osservazione di alcuni impianti di teleriscaldamento alimentati a cippato di legno recentemente realizzati in provincia di Firenze, appare quale principale criticità la disponibilità di materia prima proveniente da una filiera corta e locale. Il presente studio, individuati nella Riserva Naturale Biogenetica di Vallombrosa (FI) alcuni popolamenti rappresentativi delle realtà locali toscane, si propone di testare il full tree system quale metodo di lavoro più opportuno per le operazione di utilizzazione forestale in boschi di conifere. Detto metodo permette di razionalizzare l'assortimentazione del materiale ritraibile: tondame da sega; tondame da cartiera/imballaggio; residui vocati alla cippatura. Si ottimizzano le operazioni grazie ad un livello di meccanizzazione medio-elevato, accrescendo i livello di sicurezza per gli operai e potenziandone la professionalità. Non ultima la garanzia della necessaria sostenibilità finanziaria dell'intervento.
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Liu, Baozhu. "Full-duplex 60 GHz band dense wavelength division multiplexing star tree architecture for radio-over-fiber systems." Thesis, 2004. http://spectrum.library.concordia.ca/8396/1/MR04383.pdf.
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In this work, full-duplex 60GHz DWDM star tree architecture for radio-over-fiber systems is investigated. New approach by using DWDM with the channel spacing of 25 GHz for the first time is proposed to improve the spectral efficiency. The demonstration system consists of 1 central station and 3 base stations as an example. In addition, the remote light source technique is utilized to simplify the architecture of base station (BS) and the external modulation technique is adopted to overcome the fiber chromatic dispersion. Especially, the MZ modulator, configured to generate optical single sideband (OSSB) signal, is adopted in the central station and modulates the optical carrier with the lower sideband (LSB) and upper sideband (USB) subcarriers simultaneously with different data and the EA modulator is adopted in the base station for implementing the maintenance-free BS in the future. The error-free transmission via the 25 km uplink and downlink fiber with the data rate of 155.52 Mbps is performed. The impact of the laser linewidth and the bandwidth of the electrical bandpass filter are investigated. It concludes that the system performance is limited by the laser phase noise for considered DPSK signal and the bandwidth of electrical bandpass filter is much larger than the 3-dB bandwidth. The trade-off has to be made when optimizing the laser linewidth and the bandwidth of the bandpass filter.
Books on the topic "Full tree system"
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Bejan, Adrian, and Giuseppe Grazzini, eds. Shape and Thermodynamics. Florence: Firenze University Press, 2008. http://dx.doi.org/10.36253/978-88-8453-836-9.
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Shape and Thermodynamics is a two-day international Workshop focused on the Constructal Theory of generation of configuration in nature and engineering. From the early developments related to tree configurations for the cooling of electronics, today Constructal theory is being applied to conceptual design of transportation net-works, river basins, living bodies, building materials and many other flow systems. Constructal theory is also enriching thermo-dynamics, from basic theory to design and optimization. This theory approaches design "as science", with the generation of configuration regarded as a phenomenon of all physics, based on principle (the Constructal law). For example, Constructal Theory contributes to the evolution of fuel cells, in the design of cooling channels, the optimal feeding of reactants, etc. Important applications are also found in the design of heat exchangers, district heating networks, etc. The growing scientific literature on Constructal Theory has an important Italian component, although further dissemination is timely. Moreover, the relation with other thermodynamic research areas deserves to be explored. Website: Shape and Thermodinamics
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Facchin, Andrea. Le palme muoiono in piedi al-Naḫl yamūtu wāqifan. Venice: Fondazione Università Ca’ Foscari, 2021. http://dx.doi.org/10.30687/978-88-6969-540-7.
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al-Naḫl yamūtu wāqifan (Palm Trees Wither Upright) is the first work by Tunisian writer Ibrāhīm Darġūṯī, born in El-Mahassen (Tozeur) in 1955, proponent of the experimentalism and magical realism, and known all over the Arab world for his pungent writing style. The work was published in Sfax in 1989, and is a collection of short stories devoted to the local life of al-Ǧarīd region, in southern Tunisia; to its traditions, distinctive traits and, at times, to imagination, creating a unique mixture, which is representative of Darġūṯī’s literature. Men, the desert, and palm trees are the essential elements, the three primary colours of this literary text. Stories unfold around this triad and through them its author introduces the many facets of local reality. “A hand full of sun for ʿAzīz” or “Lion’s paw” reveal an intimate relationship between nature, represented by the palm grove, and the inhabitants of that land; a sort of tacit agreement for which one has promised to take care of the other since the dawn of time. Other stories explore all the repressive elements of the system: class differences, hunger, humiliation, tyranny; in short, the loss of fundamental rights. In this sense, Darġūṯī’s work is not remission or defenceless immobility in the face of the injustices perpetrated by man on his neighbour; on the contrary, it is pure rebellion. al-Naḫl is a vivid mixture in which multiple traditions blend. It is a set of fragments of an Arab, Tunisian or Saharan setting fairy tale, or of the Islamic cultural heritage. It shows the scars left by French colonialism, or the challenge of man facing the change of times. It is a condemnation of all kinds of injustice, a cry of anguish and restlessness for the troubles of everyday life. It is a glimpse of the Ǧarīd with its mysteries, the desert that claims men’s lives, the almost metaphysical landscapes of a salt lake that was once a sea. It is the first work by Darġūṯī translated into Italian.
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Çolak, Alper H., Simay Kirca, and Ian D. Rotherham, eds. Ancient Woods, Trees and Forests. Pelagic Publishing, 2022. http://dx.doi.org/10.53061/kzad4079.
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As trees age, they become ecologically richer and more full of life. The process of a tree, wood or forest becoming ‘ancient’, however defined, involves a vast and subtle web of relations – among the trees themselves, with other organisms, with the wider landscape and with human beings. A single tree can provide a vast array of habitats which are an integral part of the complex co-evolutionary relationships evolved over its lifetime and later during its sometimes long afterlife. From ancient times until today, trees and woods have inspired artists, writers and scientists; they have shaped cultures and reverberated through belief systems. Yet worldwide, forest cover has declined dramatically over the last 1,000 years, and what remains has been more or less altered from its original condition. Today, ‘virgin forests’ are only to be found at a few sites unreachable by humans, and even then they are affected by climate change, atmospheric pollution and species extinctions. The aim of this book is to help an understanding of the web of connections relating to ancient trees and woodlands, and to offer techniques to ensure effective conservation and sustainability of this precious resource. This book considers the key issues from a range of different aspects and varied geographical locations, beginning with fundamental concepts and reflecting on the strengths and limitations of the idea of ancient trees. Individual chapters then deal with cultural heritage, the archaeology of trees, landscape history, forest rights, tree management, saproxylic insects, the importance of dead wood, practical conservation and monitoring, biodiversity, and wood pasture among many other themes. Fresh perspectives are put forward from across Europe as far as Turkey, as well as Great Britain. Overall, given the urgent need to discover, understand, conserve and restore ancient woodlands and trees, this publication will raise awareness, foster enthusiasm and inspire wonder.
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U. S Forest U.S Forest Service and Department of Agriculture, United States. Fuel Characteristic Classification System Field Sampling and Fuelbed Development Guide: FCCS Reference Fuelbed Development, Fuelbed Inputs, Descriptive Data, Fuelbed Description, Canopy, Trees. Independently Published, 2022.
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Joanna, Benjamin. Part II United Kingdom, 9 Lessons of LBIE: Reuse and Rehypothecation. Oxford University Press, 2017. http://dx.doi.org/10.1093/law/9780198755371.003.0009.
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Two notable traumas followed the failure of Lehman Brothers on 15 September 2008. The first was the catastrophic delivering that affected wholesale financial institutions in 2009, as the post-LBIE markets went into free-fall. The second was the very long delays in the return of client assets held by in the UK Lehman Brothers International (Europe) (LBIE). The systemic failure has been associated with the reuse of securities collateral in general. Some have argued that the client asset delays were associated with a category of reuse, known as rehypothecation, in particular. Regulatory reforms have been introduced with a view to addressing both. However, this chapter argues that the true lesson of both failures is not yet fully reflected in regulation. This is the profound impact of shadow banking, and the reuse of securities collateral within it, upon client asset protection and systemic risk management alike.
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Anderson, E. N. Ecologies of the Heart. Oxford University Press, 1996. http://dx.doi.org/10.1093/oso/9780195090109.001.0001.
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There is much we can learn about conservation from native peoples, says Gene Anderson. While the advanced nations of the West have failed to control overfishing, deforestation, soil erosion, pollution, and a host of other environmental problems, many traditional peoples manage their natural resources quite successfully. And if some traditional peoples mismanage the environment--the irrational value some place on rhino horn, for instance, has left this species endangered--the fact remains that most have found ways to introduce sound ecological management into their daily lives. Why have they succeeded while we have failed? In Ecologies of the Heart, Gene Anderson reveals how religion and other folk beliefs help pre-industrial peoples control and protect their resources. Equally important, he offers much insight into why our own environmental policies have failed and what we can do to better manage our resources. A cultural ecologist, Gene Anderson has spent his life exploring the ways in which different groups of people manage the environment, and he has lived for years in fishing communities in Hong Kong, Malaysia, Singapore, Tahiti, and British Columbia--as well as in a Mayan farmtown in south Mexico--where he has studied fisheries, farming, and forest management. He has concluded that all traditional societies that have managed resources well over time have done so in part through religion--by the use of emotionally powerful cultural symbols that reinforce particular resource management strategies. Moreover, he argues that these religious beliefs, while seeming unscientific, if not irrational, at first glance, are actually based on long observation of nature. To illustrate this insight, he includes many fascinating portraits of native life. He offers, for instance, an intriguing discussion of the Chinese belief system known as Feng-Shui (wind and water) and tells of meeting villagers in remote areas of Hong Kong's New Territories who assert that dragons live in the mountains, and that to disturb them by cutting too sharply into the rock surface would cause floods and landslides (which in fact it does). He describes the Tlingit Indians of the Pacific Northwest, who, before they strip bark from the great cedar trees, make elaborate apologies to spirits they believe live inside the trees, assuring the spirits that they take only what is necessary. And we read of the Maya of southern Mexico, who speak of the lords of the Forest and the Animals, who punish those who take more from the land or the rivers than they need. These beliefs work in part because they are based on long observation of nature, but also, and equally important, because they are incorporated into a larger cosmology, so that people have a strong emotional investment in them. And conversely, Anderson argues that our environmental programs often fail because we have not found a way to engage our emotions in conservation practices. Folk beliefs are often dismissed as irrational superstitions. Yet as Anderson shows, these beliefs do more to protect the environment than modern science does in the West. Full of insights, Ecologies of the Heart mixes anthropology with ecology and psychology, traditional myth and folklore with informed discussions of conservation efforts in industrial society, to reveal a strikingly new approach to our current environmental crises.
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Nash, David. Changes in Precipitation Over Southern Africa During Recent Centuries. Oxford University Press, 2017. http://dx.doi.org/10.1093/acrefore/9780190228620.013.539.
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Precipitation levels in southern Africa exhibit a marked east–west gradient and are characterized by strong seasonality and high interannual variability. Much of the mainland south of 15°S exhibits a semiarid to dry subhumid climate. More than 66 percent of rainfall in the extreme southwest of the subcontinent occurs between April and September. Rainfall in this region—termed the winter rainfall zone (WRZ)—is most commonly associated with the passage of midlatitude frontal systems embedded in the austral westerlies. In contrast, more than 66 percent of mean annual precipitation over much of the remainder of the subcontinent falls between October and March. Climates in this summer rainfall zone (SRZ) are dictated by the seasonal interplay between subtropical high-pressure systems and the migration of easterly flows associated with the Intertropical Convergence Zone. Fluctuations in both SRZ and WRZ rainfall are linked to the variability of sea-surface temperatures in the oceans surrounding southern Africa and are modulated by the interplay of large-scale modes of climate variability, including the El Niño-Southern Oscillation (ENSO), Southern Indian Ocean Dipole, and Southern Annular Mode.Ideas about long-term rainfall variability in southern Africa have shifted over time. During the early to mid-19th century, the prevailing narrative was that the climate was progressively desiccating. By the late 19th to early 20th century, when gauged precipitation data became more readily available, debate shifted toward the identification of cyclical rainfall variation. The integration of gauge data, evidence from historical documents, and information from natural proxies such as tree rings during the late 20th and early 21st centuries, has allowed the nature of precipitation variability since ~1800 to be more fully explored.Drought episodes affecting large areas of the SRZ occurred during the first decade of the 19th century, in the early and late 1820s, late 1850s–mid-1860s, mid-late 1870s, earlymid-1880s, and mid-late 1890s. Of these episodes, the drought during the early 1860s was the most severe of the 19th century, with those of the 1820s and 1890s the most protracted. Many of these droughts correspond with more extreme ENSO warm phases.Widespread wetter conditions are less easily identified. The year 1816 appears to have been relatively wet across the Kalahari and other areas of south central Africa. Other wetter episodes were centered on the late 1830s–early 1840s, 1855, 1870, and 1890. In the WRZ, drier conditions occurred during the first decade of the 19th century, for much of the mid-late 1830s through to the mid-1840s, during the late 1850s and early 1860s, and in the early-mid-1880s and mid-late 1890s. As for the SRZ, markedly wetter years are less easily identified, although the periods around 1815, the early 1830s, mid-1840s, mid-late 1870s, and early 1890s saw enhanced rainfall. Reconstructed rainfall anomalies for the SRZ suggest that, on average, the region was significantly wetter during the 19th century than the 20th and that there appears to have been a drying trend during the 20th century that has continued into the early 21st. In the WRZ, average annual rainfall levels appear to have been relatively consistent between the 19th and 20th centuries, although rainfall variability increased during the 20th century compared to the 19th.
Book chapters on the topic "Full tree system"
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Engelhardt, Yuri, and Clive Richards. "A Universal Grammar for Specifying Visualization Types." In Diagrammatic Representation and Inference, 395–403. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-86062-2_40.
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AbstractA ‘universal grammar’ for the full spectrum of visualization types is discussed. The grammar enables the analysis of any type of visualization regarding its syntactic constituents, such as the types of visual encodings and visual components that are used. Such an analysis of a type of visualization, describing its compositional syntax, can be represented as a specification tree. Colour coded tree branches between constituent types enforce the combination rules visually. We discuss how these specification trees differ from linguistic parse trees, and how visual statements differ from verbal statements. The grammar offers a basis for generating visualization options, and the potential for formalization and for machine-readable specifications. This may serve as a basis for a system providing computer-generated visualization advice.
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Janoušek, Jan, Bořivoj Melichar, Radomír Polách, Martin Poliak, and Jan Trávníček. "A Full and Linear Index of a Tree for Tree Patterns." In Descriptional Complexity of Formal Systems, 198–209. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-09704-6_18.
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Balamurugan, B. J., K. Thirusangu, and D. G. Thomas. "Algorithms for Zumkeller Labeling of Full Binary Trees and Square Grids." In Advances in Intelligent Systems and Computing, 183–92. New Delhi: Springer India, 2014. http://dx.doi.org/10.1007/978-81-322-2135-7_21.
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Khonsari, A., H. Sarbazi-Azad, and M. Ould-Khaoua. "A Performance Model of True Fully Adaptive Routing in Hypercubes." In High Performance Computing Systems and Applications, 87–101. Boston, MA: Springer US, 2003. http://dx.doi.org/10.1007/978-1-4615-0288-3_16.
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Sun, Qiang, Yuheng Sha, Xinbo Gao, Biao Hou, and Licheng Jiao. "A Fully Unsupervised Image Segmentation Algorithm Based on Wavelet-Domain Hidden Markov Tree Models." In Advanced Concepts for Intelligent Vision Systems, 507–14. Berlin, Heidelberg: Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/11558484_64.
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Laurel, Jacob, and Sasa Misailovic. "Continualization of Probabilistic Programs With Correction." In Programming Languages and Systems, 366–93. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-44914-8_14.
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AbstractProbabilistic Programming offers a concise way to represent stochastic models and perform automated statistical inference. However, many real-world models have discrete or hybrid discrete-continuous distributions, for which existing tools may suffer non-trivial limitations. Inference and parameter estimation can be exceedingly slow for these models because many inference algorithms compute results faster (or exclusively) when the distributions being inferred are continuous. To address this discrepancy, this paper presents Leios. Leios is the first approach for systematically approximating arbitrary probabilistic programs that have discrete, or hybrid discrete-continuous random variables. The approximate programs have all their variables fully continualized. We show that once we have the fully continuous approximate program, we can perform inference and parameter estimation faster by exploiting the existing support that many languages offer for continuous distributions. Furthermore, we show that the estimates obtained when performing inference and parameter estimation on the continuous approximation are still comparably close to both the true parameter values and the estimates obtained when performing inference on the original model.
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Goswami, Tanmoy. "True-Fill: A Prototype to Know Actual Fuel Filled at Petrol Pump Using Sensors for Common Indians." In Smart Innovation, Systems and Technologies, 585–92. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-5974-3_51.
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Long, Lynn E., Gregory A. Lang, and Clive Kaiser. "Sweet cherry rootstocks." In Sweet cherries, 66–85. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781786398284.0066.
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Abstract All commercial sweet cherry trees are either budded or grafted. This chapter deals with sweet cherry rootstocks. Rootstocks are used for several purposes: (i) ease for propagating and producing more trees of a superior cultivar; (ii) better adaptation to particular soil or site characteristics; and (iii) the potential improvement of production due to additional traits like precocious flowering, higher productivity, and greater or reduced scion vigor as appropriate. Unfortunately, no one rootstock can satisfy all the requirements for consistently producing high yields of large, firm fruit of premium quality. Growers are advised to consider carefully the effects of each specific scion-rootstock combination as a function of environmental and cultural practices when replanting an orchard. Selecting the proper rootstock depends not only on the management skills of the grower, but also on the scion cultivar, training system, and site climate and soil selected for the orchard. Dwarfing, semi-dwarfing and even semi-vigorous rootstocks have major economic advantages over full-size rootstocks. The development of these new, precocious rootstocks has been almost as significant to the sweet cherry industry as to the apple industry several decades ago. When compared to Mazzard, Colt and even Mahaleb, size-controlling rootstocks have allowed sweet cherry growers an opportunity to plant high density, pedestrian orchards that become profitable more quickly, are more readily protected with orchard covering systems, and promote greater labor efficiency, easier management, and a safer and more productive work environment.
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Leutgeb, Lorenz, Georg Moser, and Florian Zuleger. "Automated Expected Amortised Cost Analysis of Probabilistic Data Structures." In Computer Aided Verification, 70–91. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-13188-2_4.
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AbstractIn this paper, we present the first fully-automated expected amortised cost analysis of self-adjusting data structures, that is, of randomised splay trees, randomised splay heaps and randomised meldable heaps, which so far have only (semi-)manually been analysed in the literature. Our analysis is stated as a type-and-effect system for a first-order functional programming language with support for sampling over discrete distributions, non-deterministic choice and a ticking operator. The latter allows for the specification of fine-grained cost models. We state two soundness theorems based on two different—but strongly related—typing rules of ticking, which account differently for the cost of non-terminating computations. Finally we provide a prototype implementation able to fully automatically analyse the aforementioned case studies."Image missing"
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Polat, A. Aytekin, and A. Sarkhosh. "Environmental requirements and site selection." In The fig: botany, production and uses, 171–83. Wallingford: CABI, 2022. http://dx.doi.org/10.1079/9781789242881.0007.
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Abstract This paper explores the environmental requirements and site selection of Ficus carica. The ideal conditions for dried fig production are: temperate and rainy winters, 30-40°C summer temperatures especially in July-September, 45-50% relative humidity, alluvial, clayish-loam soil, and average annual precipitation of around 650 mm. Growing fig trees in intensive production systems under hydroponic and greenhouse conditions is an excellent alternative production system since it allows increasing leaf area index, harvest index and fruit yield in relation to the total biomass of the plant. In site selection for greenhouse production, most of the same factors as used in siting an orchard location should be considered: topography, soil and water quantity and quality, and marketing factors. In addition, the most important greenhouse factors such as light, temperature, relative humidity, precipitation and ventilation should be considered, as well as the most important marketing or economic factors such as road transportation, market accessibility (proximity to settlements, market demands), availability of services (fuel, fertilizer, disinfectant and electricity), and availability of labor.
Conference papers on the topic "Full tree system"
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Lewis, Sterling, and Jay Joseph Suter. "Requirements for a Full Drill Through Subsea Wellhead and Tree System." In IADC/SPE Drilling Conference. Society of Petroleum Engineers, 2008. http://dx.doi.org/10.2118/112723-ms.
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Heidari, Homayoun, Neil Williams, Sean Large, and Jim Byrne. "Development of a New Self-Stable Dry-Tree GoM TLP With Full Drilling Capabilities." In ASME 2008 27th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/omae2008-57772.
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SBM Atlantia has developed a Dry-Tree FourStar TLP with full drilling capability for GoM applications. This paper focuses on the unique features of the Dry-Tree FourStar by considering a typical design example. The Dry-Tree FourStar TLP considered is a 100,000 ton displacement structure with a payload of approximately 40,000 tons, designed for 4300 ft water depth. Like its wet-tree predecessor, the hull geometry follows the battered column form, which leads to increased stability for quayside integration, wet tow of the integrated system, and self-supported installation. Furthermore, the large keel footprint of the hull maximizes the efficiency of the tendon system, resulting in a more economical solution. In order to enable quay side integration of the 22,000 ton topsides onto the FourStar hull, the deck is designed as three separate interconnecting modules. The Dry-Tree FourStar hull is structurally optimized for effective load transfer through the outer-shell of the structure, resulting in significantly lower hull steel densities when compared to industry standards. The design was confirmed through a comprehensive wave basin model test campaign performed at the Offshore Technology Research Center at Texas A&M University. The model tests were performed at 1:52 scale, and utilized the latest GoM MetOcean criteria. The top-tensioned risers were included in the physical model in order to provide more realistic estimates of the hydrodynamic behavior of the TLP. The model tests confirmed the performance of the GoM Dry-Tree FourStar as a stable drilling and production platform. This paper presents the development of this TLP with emphasis on the hydrodynamic and structural aspects that are unique to the concept. It discusses the observations from the wave basin model tests, including the results of a comparison with a theoretical global performance analysis.
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Chen, Cheng, Emad Samadiani, and Bahgat Sammakia. "Compact Modeling of Fractal Tree-Shaped Microchannel Liquid Cooling Systems." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-65220.
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Demands for higher computational speed and miniaturization have already resulted in extremely high heat fluxes in microprocessors. Fractal tree-shaped microchannel liquid cooling systems are novel heat transfer enhancement systems to keep the temperature of the microprocessors in a safe range. Due to the complexity of these systems, their full field numerical modeling for simulation of the flow and temperature fields is too time consuming and costly, particularly to be used within iterative optimization algorithms. In this paper, a quick but still accurate compact modeling approach based on Flow Network Modeling (FNM) is introduced for analysis of the flow filed in fractal microchannel liquid cooling systems. The compact method is applied to a representative fractal microchannel cooling system and the obtained velocity and flow rate distribution are validated against a full Computational Fluid Dynamics (CFD)-based model for three different designs. The compact model shows good agreement with the CFD results and robustness on different designs, while requiring much less computational capability and time. Afterwards, the compact model is used for optimization of the geometry of the fractal cooling system to achieve maximum flow rate and uniform flow distribution among the channels for a fixed pressure drop.
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Georgiadis, Sofia K. "Application of Fault Tree Analysis for Signaling Systems." In 2015 Joint Rail Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/jrc2015-5708.
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Fault Tree Analysis (FTA) is one of the key safety evaluation techniques used by New York City Transit (NYCT). First developed over 50 years ago, this technique continues to provide valuable insight for failure analysis of systems. Its use is widespread in safety-critical systems analysis across industry boundaries, including defense, nuclear, aerospace, chemical [1], and transportation industries. FTAs provide a systematic, top-down methodology to safety analysis. As such, it complements other safety analysis techniques, such as Failure Modes Effect Analysis (FMEA), which is a bottom-up failure analysis [2]. Formal Methods analyses, including Theorem Proving and Model Checking, are powerful development and analysis methodologies, both used by NYCT, that provide assurance of product’s correctness and safety. With these other safety analysis techniques, the FTA continues to play a key role in the NYCT Safety Program. This paper will examine how NYCT uses FTAs for the safety analysis of microprocessor-based signaling systems. FTAs are used by NYCT throughout the system lifecycle. Initially, during the system development phase, NYCT requires system suppliers to develop Fault Tree Analyses of their systems, as a requirement for NYCT safety certification and deployment. For the system maintenance phase, NYCT uses the outputs of suppliers’ analyses to develop and enforce maintenance and operational procedures. In this manner, NYCT’s use of FTA provides full lifecycle value by providing design, maintenance, and operational insight into the causes of hazardous events. Through the examination of example fault trees and an overview of the FTA process, this paper will present the NYCT’s implementation of this powerful analysis tool, and will describe the benefits gained from using this methodology.
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Gupta, Himanshu, Vincenzo Nava, Hugh Banon, Vasileios Gkaras, and Pol Spanos. "Determination of Riser Tensioner Properties From Full-Scale Data." In ASME 2008 27th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/omae2008-57791.
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Tensioners are used for supporting various kinds of production and drilling risers on offshore platforms. All permanent production facilities (such as TLP’s and Spar’s) have employed tensioners to support their dry tree production risers. The key design parameters for the tensioners design are stiffness, stroke and friction properties. Full scale onshore testing of production riser tensioners to determine tensioner properties is difficult due to the magnitude of the loads and pressures required for typical deepwater risers, thus designers frequently rely on theoretical values or small scale tests. This paper presents a determination of riser tensioner properties from full scale offshore observations made on the Holstein Spar production facility during 2005 hurricance season. The paper presents a model for the tensioner system that relates the properties needed by platform and riser designers to the physical tensioner systems. The methodology and results from extraction of parameters from the full scale data is presented. The results presented in this paper will provide a better insight to the designers of such systems.
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Li, Yang, and Chen Hang. "The Fault Tree Analysis on Auxiliary Feedwater Pump Room Ventilation System in Pressurized Water Reactor Power." In 2013 21st International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icone21-16398.
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Main function of HVAC is to remove heat from equipment and pipeline, hold the inner condition, maintain an ambient temperature and humidity that keep the equipments function properly and easy access. Although regulation is no mandatory requirement of redundant equipment design and preservation function in case of specified disaster or man-made accident. In fact, It does be influenced by the incident whether partial failure or full. The hazard factor determination and qualitative analysis are based on fault tree analysis through simulated mode from selected the typical system. The identification of accident cause, hazard cause and fault mode is essential for improving system reliability. According the analysis result, It will be optimization factor such as installation and design process, maintenance ability, material plan, corrosion preventing. It’s helpful to control hazard under accepted level. This method given in the article is a new way to treat HVAC system in pressurized water reactor nuclear power. It hopes that this method will lead to reduce accident loss, save maintenance fee, bring economic benefits and improve the risk of nuclear power.
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Di´az-Herna´dez, Alejandro, and Mari´a Eloi´sa Pe´rez Medina. "Reliability Characteristics of a Safety Instrumented System via Markov Analysis." In ASME 2004 23rd International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2004. http://dx.doi.org/10.1115/omae2004-51456.
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The Markov technique for determining the Reliability Characteristics (Probability of Failure on Demand, availability, Mean time to repair and Mean time between failures) of the Safety Instrumented System (SIS) on Offshore Metering and Custody Transfer Facility in Campeche Bay Mexico is presented in this work. Two important factors were considered based on the ISA TR84.0.02, Part 4: a) Common Cause Failure and b) the diagnostics capabilities were taking into account. The Markov technique methodology employed in order to assess and determine the Reliability characteristics of SIS was compared with Fault Tree Analysis previously analyzed, Part 3 of ISA TR84.0.02; for which the hazard and risk analysis mandated a SIL 2 for the SIS with two sets of sensors where each individual sensor can shut down the operation of the facility. Aspects like voting, redundancy or diversity bring about a full Markov model of a SIS, but it usually consists of intermediates states not significant for the assessment of the reliability characteristics. The quantitative results will mostly depend on the direct transitions to the fail-safe and fail-dangerous states. As a result, in most cases it was not necessary to present a fully developed model.
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Liew, William Sin Yoong, El Khalil Heboul, Mohamad Shahril Majid Bin Allapitchai, Sattiyaraju Sellapan, Ahmad Luqman Bin Johan, Ahmad Hafizi Bin Ahmad Zaini, Mohd Hairi Bin Abdul Razak, Puteri Dharmilla Syafawati Binti Dharma Dian, Ahmad Zharif Bin Abdullah, and William Zomerdijk. "A Novel Approach to First in the World Retrieval of Open Water Vertical Xmas Tree." In Abu Dhabi International Petroleum Exhibition & Conference. SPE, 2021. http://dx.doi.org/10.2118/207376-ms.
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Abstract Wells plug & abandonment was carried out in a deepwater field (Field C) offshore West Africa. There were 15 deepwater subsea wells in this field. Thirteen of the wells were completed with Open Water Vertical Xmas Tree (OXT) while remaining two were completed with Enhanced Vertical Xmas Tree (EVXT). In the wells with Open Water Vertical Xmas Tree (OXT), the upper completion tubing and hanger were ran together with the Xmas Tree in a single run. This posed challenges to Operator in retrieving the Xmas Tree. This paper will discuss the novel approach used by Operator in the OXT retrieval. Due to the design of OXT which was different from most of the vertical Xmas Trees (XT) in the world, there were a few challenges in the process of XTs retrieval. If the XTs and upper completion tubing were retrieved in reversal of the way it was completed, it will exposed the well to prolonged duration of single barrier until a BOP can be latched on for subsequent activities. On top of that, the Original Equipment Manufacturer's Completion Workover Riser (CWOR) system and Support Landing Structure (SLS) was not available in full package to be utilized in this project. Furthermore, there were constraints on the rig moonpool space, handling of OXT on surface and clashes between the rig's BOP and existing subsea structures. In managing the risk of well exposure to single proven and monitored barrier during the process of OXT retrieval, Operator has evaluated a few options and came out with a novel approach in the OXT retrieval which managed to minimize exposure time and reduce risk in operations. In contrary to the original principle of well completion here, after a barrier was established in the well, the OXTs was retrieved separately from the upper completion tubing to allow rig BOP to be latched onto wellhead in shortest possible time. To achieve this objective, operations was planned to be carried out on a dual activity derrick rig. Meanwhile, a non-OEM rental CWOR system was used together with Tree Running Tool from the OEM CWOR system to access the wells for intervention work and subsequently retrieve the OXTs. By doing this, the combined CWOR stack exceeded the height limitation at the rig's moonpool. Some modifications were carried out to allow the operations to happen. A novel approach was also used to handle the OXT on surface without the OEM Support Landing Structure - which simplified the operations and reduced HSE risks. Solution was also put into place to enable latching of the rig BOP onto wellheads on Drill Centre although there were risk of clashing initially.
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Kyoung, Johyun, Chan-Kyu Yang, Kostas Lambrakos, and Jim O’Sullivan. "Model Tests With the HVS Semisubmersible for Dry Tree Application." In ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/omae2014-23965.
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The global hull motion performance of the HVS semisubmersible for dry tree application is investigated with model tests. The HVS semisubmersible, which has been validated for low heave motion and VIM (Vortex Induced Motion) response, was modified for dry tree application. As a base case, the modification includes a keel plate with riser keel guides at the level of the pontoons. The keel plate is optimally designed to increase the hull heave period to compensate for the heave period reduction in the HVS semisubmersible due to the riser tensioners for the dry tree application. The plate also provides additional viscous damping that decreases the heave response at the heave natural period. The model tests were performed to investigate the in-place hull motion performance for the Gulf of Mexico environmental conditions. The pneumatic riser tensioners were modeled using a spring with dual stiffness. Because of the water depth limit in the wave basin, a truncated mooring was used to simulate the full scale prototype mooring system. An alternate modification to the HVS semisubmersible that includes pontoon plates was also tested and the measured response was compared to the response of the base case. The measured hull responses were correlated with MLTSIM, a Technip in-house nonlinear time-domain 6-DOF motion analysis program.
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Sches, Ce´line, and Roy Shilling. "Design and Qualification of Fatigue Resistant Heavy Wall Threaded and Coupled Premium Connectors for Drilling and Production Riser Applications in Deepwater HPHT Dry Tree Systems." In ASME 2010 29th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2010. http://dx.doi.org/10.1115/omae2010-20904.
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In the late 2006, as a part of its GoM HPHT technology program, BP initiated with V&M the design and qualification of a 15k dual barrier dry tree production riser system capable of being installed in water depths up to 10,000 ft. This was driven by the fact that X-80 riser systems became so heavy that they were not considered workable, whereas switching to higher strength steel and T&C connector designs made the systems much lighter and became enabling technologies for dry trees. Developments concern an 11 3/4″ OD with 1.1″ wall thickness C-110 sour service resistant material as the inner riser rated to 15k, a 16″ OD with 1″ wall thickness Q-125 material as the outer riser rated to 10k, and a 21″ OD with 1″ wall thickness Q-125 material as the drilling riser rated to 10k. The specification called for all three connections to be designed with an external environmental metal to metal seal, and superior fatigue performance. Based on existing know-how on fatigue resistant T&C connectors, the development work started with the 11 3/4″ inner riser, with a need to accommodate existing design rules for such a heavy pipe. A comprehensive evaluation program was built, with a total of 39 samples including 5 design variations, and full scale tests combining Make & Break, sealability, fatigue, and thermal cycles. The qualification was completed with a connector achieving over 25 M&B and a stress factor less than 1.5 compared to DNV-B1 curve, that is a stress factor matching DNV-C. With success on the 11 3/4″ and some lessons learned along the way, focus was then shifted to the 16″ outer riser. Key issues were identified here concerning the surface treatment quality of the metal to metal seals when combining large sliding distance and high contact pressure. The 21″ drilling riser development is on-going. As we near full product qualification, we focus on final optimizations to ensure easy field running. This paper will prove the robustness of the design process elaborated to develop heavy wall riser T&C premium connectors, leading to outstanding fatigue performance and fatigue compliant internal and external environmental metal to metal seals. Such results prove the applicability of T&C for dry tree HPHT systems, and further establish the potential of T&C to be used for SCR and Flowline applications.
Reports on the topic "Full tree system"
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Galili, Naftali, Roger P. Rohrbach, Itzhak Shmulevich, Yoram Fuchs, and Giora Zauberman. Non-Destructive Quality Sensing of High-Value Agricultural Commodities Through Response Analysis. United States Department of Agriculture, October 1994. http://dx.doi.org/10.32747/1994.7570549.bard.
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The objectives of this project were to develop nondestructive methods for detection of internal properties and firmness of fruits and vegetables. One method was based on a soft piezoelectric film transducer developed in the Technion, for analysis of fruit response to low-energy excitation. The second method was a dot-matrix piezoelectric transducer of North Carolina State University, developed for contact-pressure analysis of fruit during impact. Two research teams, one in Israel and the other in North Carolina, coordinated their research effort according to the specific objectives of the project, to develop and apply the two complementary methods for quality control of agricultural commodities. In Israel: An improved firmness testing system was developed and tested with tropical fruits. The new system included an instrumented fruit-bed of three flexible piezoelectric sensors and miniature electromagnetic hammers, which served as fruit support and low-energy excitation device, respectively. Resonant frequencies were detected for determination of firmness index. Two new acoustic parameters were developed for evaluation of fruit firmness and maturity: a dumping-ratio and a centeroid of the frequency response. Experiments were performed with avocado and mango fruits. The internal damping ratio, which may indicate fruit ripeness, increased monotonically with time, while resonant frequencies and firmness indices decreased with time. Fruit samples were tested daily by destructive penetration test. A fairy high correlation was found in tropical fruits between the penetration force and the new acoustic parameters; a lower correlation was found between this parameter and the conventional firmness index. Improved table-top firmness testing units, Firmalon, with data-logging system and on-line data analysis capacity have been built. The new device was used for the full-scale experiments in the next two years, ahead of the original program and BARD timetable. Close cooperation was initiated with local industry for development of both off-line and on-line sorting and quality control of more agricultural commodities. Firmalon units were produced and operated in major packaging houses in Israel, Belgium and Washington State, on mango and avocado, apples, pears, tomatoes, melons and some other fruits, to gain field experience with the new method. The accumulated experimental data from all these activities is still analyzed, to improve firmness sorting criteria and shelf-life predicting curves for the different fruits. The test program in commercial CA storage facilities in Washington State included seven apple varieties: Fuji, Braeburn, Gala, Granny Smith, Jonagold, Red Delicious, Golden Delicious, and D'Anjou pear variety. FI master-curves could be developed for the Braeburn, Gala, Granny Smith and Jonagold apples. These fruits showed a steady ripening process during the test period. Yet, more work should be conducted to reduce scattering of the data and to determine the confidence limits of the method. Nearly constant FI in Red Delicious and the fluctuations of FI in the Fuji apples should be re-examined. Three sets of experiment were performed with Flandria tomatoes. Despite the complex structure of the tomatoes, the acoustic method could be used for firmness evaluation and to follow the ripening evolution with time. Close agreement was achieved between the auction expert evaluation and that of the nondestructive acoustic test, where firmness index of 4.0 and more indicated grade-A tomatoes. More work is performed to refine the sorting algorithm and to develop a general ripening scale for automatic grading of tomatoes for the fresh fruit market. Galia melons were tested in Israel, in simulated export conditions. It was concluded that the Firmalon is capable of detecting the ripening of melons nondestructively, and sorted out the defective fruits from the export shipment. The cooperation with local industry resulted in development of automatic on-line prototype of the acoustic sensor, that may be incorporated with the export quality control system for melons. More interesting is the development of the remote firmness sensing method for sealed CA cool-rooms, where most of the full-year fruit yield in stored for off-season consumption. Hundreds of ripening monitor systems have been installed in major fruit storage facilities, and being evaluated now by the consumers. If successful, the new method may cause a major change in long-term fruit storage technology. More uses of the acoustic test method have been considered, for monitoring fruit maturity and harvest time, testing fruit samples or each individual fruit when entering the storage facilities, packaging house and auction, and in the supermarket. This approach may result in a full line of equipment for nondestructive quality control of fruits and vegetables, from the orchard or the greenhouse, through the entire sorting, grading and storage process, up to the consumer table. The developed technology offers a tool to determine the maturity of the fruits nondestructively by monitoring their acoustic response to mechanical impulse on the tree. A special device was built and preliminary tested in mango fruit. More development is needed to develop a portable, hand operated sensing method for this purpose. In North Carolina: Analysis method based on an Auto-Regressive (AR) model was developed for detecting the first resonance of fruit from their response to mechanical impulse. The algorithm included a routine that detects the first resonant frequency from as many sensors as possible. Experiments on Red Delicious apples were performed and their firmness was determined. The AR method allowed the detection of the first resonance. The method could be fast enough to be utilized in a real time sorting machine. Yet, further study is needed to look for improvement of the search algorithm of the methods. An impact contact-pressure measurement system and Neural Network (NN) identification method were developed to investigate the relationships between surface pressure distributions on selected fruits and their respective internal textural qualities. A piezoelectric dot-matrix pressure transducer was developed for the purpose of acquiring time-sampled pressure profiles during impact. The acquired data was transferred into a personal computer and accurate visualization of animated data were presented. Preliminary test with 10 apples has been performed. Measurement were made by the contact-pressure transducer in two different positions. Complementary measurements were made on the same apples by using the Firmalon and Magness Taylor (MT) testers. Three-layer neural network was designed. 2/3 of the contact-pressure data were used as training input data and corresponding MT data as training target data. The remaining data were used as NN checking data. Six samples randomly chosen from the ten measured samples and their corresponding Firmalon values were used as the NN training and target data, respectively. The remaining four samples' data were input to the NN. The NN results consistent with the Firmness Tester values. So, if more training data would be obtained, the output should be more accurate. In addition, the Firmness Tester values do not consistent with MT firmness tester values. The NN method developed in this study appears to be a useful tool to emulate the MT Firmness test results without destroying the apple samples. To get more accurate estimation of MT firmness a much larger training data set is required. When the larger sensitive area of the pressure sensor being developed in this project becomes available, the entire contact 'shape' will provide additional information and the neural network results would be more accurate. It has been shown that the impact information can be utilized in the determination of internal quality factors of fruit. Until now,
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Bar-Joseph, Moshe, William O. Dawson, and Munir Mawassi. Role of Defective RNAs in Citrus Tristeza Virus Diseases. United States Department of Agriculture, September 2000. http://dx.doi.org/10.32747/2000.7575279.bard.
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This program focused on citrus tristeza virus (CTV), the largest and one of the most complex RNA-plant-viruses. The economic importance of this virus to the US and Israeli citrus industries, its uniqueness among RNA viruses and the possibility to tame the virus and eventually turn it into a useful tool for the protection and genetic improvement of citrus trees justify these continued efforts. Although the overall goal of this project was to study the role(s) of CTV associated defective (d)-RNAs in CTV-induced diseases, considerable research efforts had to be devoted to the engineering of the helper virus which provides the machinery to allow dRNA replication. Considerable progress was made through three main lines of complementary studies. For the first time, the generation of an engineered CTV genetic system that is capable of infecting citrus plants with in vitro modified virus was achieved. Considering that this RNA virus consists of a 20 kb genome, much larger than any other previously developed similar genetic system, completing this goal was an extremely difficult task that was accomplished by the effective collaboration and complementarity of both partners. Other full-length genomic CTV isolates were sequenced and populations examined, resulting in a new level of understanding of population complexities and dynamics in the US and Israel. In addition, this project has now considerably advanced our understanding and ability to manipulate dRNAs, a new class of genetic elements of closteroviruses, which were first found in the Israeli VT isolate and later shown to be omnipresent in CTV populations. We have characterized additional natural dRNAs and have shown that production of subgenomic mRNAs can be involved in the generation of dRNAs. We have molecularly cloned natural dRNAs and directly inoculated citrus plants with 35S-cDNA constructs and have shown that specific dRNAs are correlated with specific disease symptoms. Systems to examine dRNA replication in protoplasts were developed and the requirements for dRNA replication were defined. Several artificial dRNAs that replicate efficiently with a helper virus were created from infectious full-genomic cDNAs. Elements that allow the specific replication of dRNAs by heterologous helper viruses also were defined. The T36-derived dRNAs were replicated efficiently by a range of different wild CTV isolates and hybrid dRNAs with heterologous termini are efficiently replicated with T36 as helper. In addition we found: 1) All CTV genes except of the p6 gene product from the conserved signature block of the Closteroviridae are obligate for assembly, infectivity, and serial protoplast passage; 2) The p20 protein is a major component of the amorphous inclusion bodies of infected cells; and 3) Novel 5'-Co-terminal RNAs in CTV infected cells were characterized. These results have considerably advanced our basic understanding of the molecular biology of CTV and CTV-dRNAs and form the platform for the future manipulation of this complicated virus. As a result of these developments, the way is now open to turn constructs of this viral plant pathogen into new tools for protecting citrus against severe CTV terms and development of virus-based expression vectors for other citrus improvement needs. In conclusion, this research program has accomplished two main interconnected missions, the collection of basic information on the molecular and biological characteristics of the virus and its associated dRNAs toward development of management strategies against severe diseases caused by the virus and building of novel research tools to improve citrus varieties. Reaching these goals will allow us to advance this project to a new phase of turning the virus from a pathogen to an ally.
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Law, Edward, Samuel Gan-Mor, Hazel Wetzstein, and Dan Eisikowitch. Electrostatic Processes Underlying Natural and Mechanized Transfer of Pollen. United States Department of Agriculture, May 1998. http://dx.doi.org/10.32747/1998.7613035.bard.
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The project objective was to more fully understand how the motion of pollen grains may be controlled by electrostatic forces, and to develop a reliable mechanized pollination system based upon sound electrostatic and aerodynamic principles. Theoretical and experimental analyses and computer simulation methods which investigated electrostatic aspects of natural pollen transfer by insects found that: a) actively flying honeybees accumulate ~ 23 pC average charge (93 pC max.) which elevates their bodies to ~ 47 V likely by triboelectrification, inducing ~ 10 fC of opposite charge onto nearby pollen grains, and overcoming their typically 0.3-3.9 nN detachment force resulting in non-contact electrostatic pollen transfer across a 5 mm or greater air gap from anther-to-bee, thus providing a theoretical basis for earlier experimental observations and "buzz pollination" events; b) charge-relaxation characteristics measured for flower structural components (viz., 3 ns and 25 ns time constants, respectively, for the stigma-style vs. waxy petal surfaces) ensure them to be electrically appropriate targets for electrodeposition of charged pollen grains but not differing sufficiently to facilitate electrodynamic focusing onto the stigma; c) conventional electrostatic focusing beneficially concentrates pollen-deposition electric fields onto the pistill tip by 3-fold as compared to that onto underlying flower structures; and d) pollen viability is adequately maintained following exposure to particulate charging/management fields exceeding 2 MV/m. Laboratory- and field-scale processes/prototype machines for electrostatic application of pollen were successfully developed to dispense pollen in both a dry-powder phase and in a liquid-carried phase utilizing corona, triboelectric, and induction particulate-charging methods; pollen-charge levels attained (~ 1-10 mC/kg) provide pollen-deposition forces 10-, 77-, and 100-fold greater than gravity, respectively, for such charged pollen grains subjected to a 1 kV/cm electric field. Lab and field evaluations have documented charged vs. ukncharged pollen deposition to be significantly (a = 0.01-0.05) increased by 3.9-5.6 times. Orchard trials showed initial fruit set on branches individually treated with electrostatically applied pollen to typically increase up to ~ 2-fold vs. uncharged pollen applications; however, whole-tree applications have not significantly shown similar levels of benefit and corrective measures continue. Project results thus contribute important basic knowledge and applied electrostatics technology which will provide agriculture with alternative/supplemental mechanized pollination systems as tranditional pollen-transfer vectors are further endangered by natural and man-fade factors.
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Kahima, Samuel, Solomon Rukundo, and Victor Phillip Makmot. Tax Certainty? The Private Rulings Regime in Uganda in Comparative Perspective. Institute of Development Studies, January 2021. http://dx.doi.org/10.19088/ictd.2021.001.
Full textAbstract:
Taxpayers sometimes engage in complex transactions with uncertain tax treatment, such as mergers, acquisitions, demergers and spin-offs. With the rise of global value chains and proliferation of multinational corporations, these transactions increasingly involve transnational financial arrangements and cross-border dealings, making tax treatment even more uncertain. If improperly structured, such transactions could have costly tax consequences. One approach to dealing with this uncertainty is to create a private rulings regime, whereby a taxpayer applies for a private ruling by submitting a statement detailing the transaction (proposed or completed) to the tax authority. The tax authority interprets and applies the tax laws to the requesting taxpayer’s specific set of facts in a written private ruling. The private ruling offers taxpayers certainty as to how the tax authority views the transaction, and the tax treatment the taxpayer can expect based on the specific facts presented. Private rulings are a common feature of many tax systems around the world, and their main goal is to promote tax certainty and increase investor confidence in the tax system. This is especially important in a developing country like Uganda, whose tax laws are often amended and may not anticipate emerging transnational tax issues. Private rulings in Uganda may be applied for in writing prior to or after engaging in the transaction. The Tax Procedures Code Act (TPCA), which provides for private rulings, requires applicants to make a full and true disclosure of the transaction before a private ruling may be issued. This paper evaluates the Ugandan private rulings regime, offering a comparative perspective by highlighting similarities and contrasts between the Ugandan regime and that of other jurisdictions, including the United States, Australia, South Africa and Kenya. The Ugandan private rulings regime has a number of strengths. It is not just an administrative measure as in some jurisdictions, but is based on statute. Rulings are issued from a central office – instead of different district offices, which may result in conflicting rulings. Rather than an elaborate appeals process, the private ruling is only binding on the URA and not on the taxpayer, so a dissatisfied taxpayer can simply ignore the ruling. The URA team that handles private rulings has diverse professional backgrounds, which allows for a better understanding of applications. There are, however, a number of limitations of the Ugandan private rulings system. The procedure of revocation of a private ruling is uncertain. Private rulings are not published, which makes them a form of ‘secret law’. There is no fee for private rulings, which contributes to a delay in the process of issuing one. There is understaffing in the unit that handles private rulings. Finally, there remains a very high risk of bias against the taxpayer because the unit is answerable to a Commissioner whose chief mandate is collection of revenue. A reform of the private rulings regime is therefore necessary, and this would include clarifying the circumstances under which revocation may occur, introducing an application fee, increasing the staffing of the unit responsible, and placing the unit under a Commissioner who does not have a collection mandate. While the private rulings regime in Uganda has shortcomings, it remains an essential tool in supporting investor confidence in the tax regime.
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Tanksley, Steven D., and Dani Zamir. Development and Testing of a Method for the Systematic Discovery and Utilization of Novel QTLs in the Production of Improved Crop Varieties: Tomato as a Model System. United States Department of Agriculture, June 1995. http://dx.doi.org/10.32747/1995.7570570.bard.
Full textAbstract:
Modern cultivated varieties carry only a small fraction of the variation present in the gene pool. The narrow genetic basis of modern crop plants is a result of genetic bottlenecks imposed during early domestication and modern plant breeding. The wild ancestors of most crop plants can still be found in their natural habitats and Germplasm Centers have been established to collect and maintain this material. These wild and unadapted resources can potentially fuel crop plant improvement efforts for many years into the future (Tanksley and McCouch 1997). Unfortunately, scientists have been unable to exploit the majority of the genetic potential warehoused in germplasm repositories. This is especially true as regards to the improvement of quantitative traits like yield and quality. One of the major problems is that much of the wild germplasm is inferior to modern cultivars for many of the quantitative traits that breeders would like to improve. Our research, focusing on the tomato as a model system, has shown that despite their inferior phenotypes, wild species are likely to contain QTLs that can substantially increase the yield and quality of elite cultivars (de Vicente and Tanksley 1992, Eshed and Zamir 1994, Eshed et al. 1996). Using novel population structures of introgression lines (ILs; Eshed and Zamir 1995) and advanced backcross lines (AB; Tanksley et al. 1996) we identified and introduced valuable QTLs from unadapted germplasm into elite processing tomato varieties. Populations involving crosses with five Lycopersicon species (L. pennellii (Eshed and Zamir 1994; Eshed et al. 1996; Eshed and Zamir 1996), L. hirsutum (Bernacchi et al. 1998), L. pimpinellifolium (Tanksley et al. 1996), L. parviflorum (unpub.), L. peruvianum (Fulton et al. 1997) have been field and laboratory tested in a number of locations around the world. QTLs from the wild parent were identified that improve one or more of the key quantitative traits for processing tomatoes (yield, brix, sugar and acid composition and earliness) by as much as 10-30%. Nearly isogenic lines (QTL-NILs) have been generated for a subset of these QTLs. Each QTL-NIL contains the entire genome of the elite cultivated parent except for a segment (5-40 cM) of the wild species genome corresponding to a specific QTL. The genetic material and information that was developed in this program is presently used by American and Israeli seed companies for the breeding of superior varieties. We expect that in the next few years these varieties will make a difference in the marketplace.