Articles de revues : « Full tree system »

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MacDonell, Marc R., et Arthur Groot. « Harvesting peatland black spruce : Impacts on advance growth and site disturbance ». Forestry Chronicle 73, n^o 2 (1 avril 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, n^o 4 (juillet 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 et H. F. TOMLINSON. « INTERACTIONS BETWEEN NÉRÉ (PARKIA BIGLOBOSA) AND UNDER-PLANTED SORGHUM IN A PARKLAND SYSTEM IN BURKINA FASO ». Experimental Agriculture 34, n^o 1 (janvier 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 et Bahar Fallahi. « Irrigation and Rootstocks Affect Water Use, Growth, Nutrition, Yield, and Fruit Quality of `Fuji' and `Gala' Apples ». HortScience 41, n^o 4 (juillet 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 et 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, n^o 5 (mai 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 et 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, n^o 1 (janvier 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, et Peer Bork. « Interactive Tree Of Life (iTOL) v4 : recent updates and new developments ». Nucleic Acids Research 47, W1 (1 avril 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 et Corrado Costa. « A Full Technological Traceability System for Extra Virgin Olive Oil ». Foods 9, n^o 5 (13 mai 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 et Bianca Midori Souza Sekiya. « Growth and yield of corn forage intercropped with marandu grass in an agrosilvopastoral system with eucalyptus ». Semina : Ciências Agrárias 38, n^o 6 (23 novembre 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 et Bahman Shafii. « Efficient Irrigation for Optimum Fruit Quality and Yield in Apples ». HortScience 45, n^o 11 (novembre 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.

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Grieve, AM. « Water use efficiency, nutrient uptake and productivity of micro-irragated citrus ». Australian Journal of Experimental Agriculture 29, n^o 1 (1989) : 111. http://dx.doi.org/10.1071/ea9890111.

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The comparative patterns of water and nutrient uptake, soil salinity and water use efficiency resulting from 2 irrigation systems were studied in a 20-year-old Valencia orange orchard in Sunraysia on the Murray River. A conventional full ground cover system with the sprinklers in the middle of the rows operated at 14 day intervals (peak water demand), was compared with a partial (60-65%) ground cover system using under-tree micro-sprinklers operated at 7-day intervals. Irrigation applications were calculated to replace water depleted from the soil (including a leaching fraction) and were scheduled using tensiometers. During the 4 years of the experiment, approx. 10% less water was applied using micro-sprinklers. The average measured values for the crop coefficients were 0.62 (micro-irrigated) and 0.64 (full ground cover) during midsummer. Measurement of soil water extraction patterns by plant roots showed that only 5% of water use occurred below 1.0 m in under-tree microsprinkler irrigated trees, whereas 17% of water was taken up below this depth by trees irrigated with the mid-row system. Water uptake was limited by water availability rather than root density and declined sharply in mid-row irrigated trees during the second half of the 14-day irrigation cycle, when lower values of soil matric potential and shoot water potential were observed. Root distribution reflected these water uptake patterns with the highest density of fine roots in the 30-60 cm layer. Fertiliser injection with the micro-sprinkler system significantly increased the efficiency of N and P uptake compared with surface application, whereas leaf K levels were lower under micro-irrigation. Soil and plant levels of Na and C1 were low and unaffected by irrigation system during the experiment indicating adequate leaching of salt occurred with both systems. Fruit yield averaged 12% (5 t/ha) higher from micro-irrigated trees due to higher fruit numbers in light crop years. Tree growth was depressed in micro-irrigated trees suggesting a change in the partitioning of photosynthetic energy from vegetative to reproductive growth. The net effect of micro-irrigation was to increase water use efficiency by 22%, from 3.56 to 4.34 t fruit per ML applied water. No adverse effects on orchard productivity were observed following conversion from full to partial wetting of the soil surface. Under-tree micro-irrigation can therefore be recommended as a practical and efficient system for citrus irrigation in the irrigation areas of the Murray River.

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Jelavić, Edo, Dominic Jud, Pascal Egli et Marco Hutter. « Robotic Precision Harvesting : Mapping, Localization, Planning and Control for a Legged Tree Harvester ». Field Robotics 2, n^o 1 (10 mars 2022) : 1386–431. http://dx.doi.org/10.55417/fr.2022046.

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This paper presents a system for autonomously conducting precision harvesting missions using a legged harvester. Precision tree harvesting removes some trees selectively, while leaving neighboring trees intact. Our robot performs the challenging task of navigation and tree grabbing in a confined, GPS-denied forest environment. We propose strategies for mapping, localization, planning, and control and integrate them into a fully autonomous system. The mission starts with a human mapping the area of interest using a detachable, custom sensor module. Subsequently, a human expert selects the specific trees for harvesting. The sensor module is then mounted on the machine and used for localization within the created map. A planning algorithm searches for both an approach-pose and a path in a single path planning problem. We design a path-following controller exploiting the legged harvester’s capabilities for negotiating rough terrain. Upon reaching the approach-pose, the machine grabs a tree with a general-purpose gripper. Our system has been tested in both emulated and natural forest settings. To the best of our knowledge, ours is the first robot to demonstrate such a level of autonomy on a full-size, hydraulic machine operating in a realistic environment.

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Zhu, Yurui, Zhengyuan Lu, Mingshi Feng, Jun Wang et Zhipeng Li. « An improved method to characterize the full-scale pore system and dual pore model of tight sands ». Interpretation 8, n^o 3 (23 mars 2020) : SL9—SL23. http://dx.doi.org/10.1190/int-2019-0147.1.

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Tight sands have pore systems with complex structures and widely distributed pore sizes. We have studied the characteristics of these pore systems to better understand their important role in the accumulation and migration mechanisms of oil and gas reservoirs, which may enhance our ability to evaluate reservoir quality and predict reservoir production. To this end, we carried out thin-section analysis, scanning electron microscopy, pressure-controlled porosimetry (PCP), and rate-controlled porosimetry (RCP) to describe the pore systems of a typical tight-sand reservoir in East Asia. We improved a differential-distribution-based splicing method to reveal the full-scale pore systems using PCP and RCP. We found that the typical pore radius distribution in our target reservoir exhibits two peaks: at radius [Formula: see text] and at radius [Formula: see text]. Based on pore shapes and connections, intergranular pores are network structures and clay-host pores are tree-like structures. Intragranular pores, in contrast, can be different structures under different conditions. If wide throats are present, intragranular pores function as typical tree-like pores; if throats are narrow, they serve as the pore parts of a network-pore system. Network pores are the primary contributors to porosity and permeability, whereas tree-like pores mainly contribute to porosity. In some high-clay sands, however, the tree-like pores may also contribute to permeability. Based on their fractal characteristics, we divided the pore systems of tight sands into three types: (1) a network-structure-controlled intergranular pore system, (2) a tree-like-structure-controlled clay-host pore system, and (3) a network-structure-controlled intergranular-intragranular pore system.

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Luo, Ruilong, Yonghuan Guo, Fang Wang, Youjie Li, Shuai Li, Jinfei Zhang et Zhe Jiang. « Fault Tree Analysis of a Full-Ocean-Depth Unmanned Submersible ». Marine Technology Society Journal 56, n^o 4 (23 août 2022) : 106–19. http://dx.doi.org/10.4031/mtsj.56.4.3.

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Abstract Due to the rising demands for applications in extreme environments and technological breakthroughs, today's marine equipment system is increasingly intricate and powerful. As a result, the issue of reliability is gaining prominence. One of the most efficient approaches in reliability analysis is Fault Tree Analysis (FTA). The FTA method and the Monte Carlo simulation were used to access the system reliability of a full-ocean-depth unmanned submersible (FODUS). The life distribution function of the system is determined, and the FODUS system's Mean Time Between Failures and the importance index of each basic component are calculated. The results will serve as a reference for future research on the reliability of deep-sea submersibles.

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Elfying, D. C. « EFFECTS OF TREE SUPPORT AND TRAINING SYSTEM ON APPLE TREE GROWTH AND PRODUCTIVITY ». HortScience 27, n^o 6 (juin 1992) : 620a—620. http://dx.doi.org/10.21273/hortsci.27.6.620a.

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'Empire' (E) and 'Marshall McIntosh' (MM)/'Mark' trees planted in 1986 were trained to the freestanding central leader (CL), central leader with annual extension-shoot heading (HCL), slender spindle (SS) or vertical axis (VA). Support with a full tree stake (SS & VA) had little effect on shoot growth. HCL increased shoot number and mean length. Fewer pruning cuts were made on supported trees, while more were made on HCL trees. Dry weight of prunings 1989-91 was the same for all MM trees, while in E trees, CL and SS had lower pruning weights than HCL and VA. Bloom density was uninfluenced by support or training. Fruit set was greater in 1990 and 1991 on supported E trees, and in 1990 on supported MM trees. Yield was greater on supported systems in 3 out of 4 production years. Total yield after 6 years of age was 26-38% greater for supported trees of both cultivars. Bienniality was reduced about 15% by support in MM trees but unaffected by support or training in E trees. Net total crop value (estimated annual crop value minus annual harvest cost and support cost, if applicable, annual 10% discount rate) in 1991 was approximately $1600 per ha greater for supported E trees and $270 per ha greater for supported MM trees.

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Flore, J. A., et D. R. Layne. « ORCHARD DESIGN OF SOUR CHERRY IS YIELD RELATED TO LIGHT INTERCEPTION ? » HortScience 25, n^o 9 (septembre 1990) : 1135a—1135. http://dx.doi.org/10.21273/hortsci.25.9.1135a.

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The objective of this experiment was to design orchard systems and tree shapes that optimize production based upon light interception. `Montmoreney' on `Mahaleb' rootstock was established at the Clarksville Horticultural Research Station in 1982. The following factors were investigated: a) tree shape; free form, Δ triangle and • rectangle, b) tree height to clear alleyway width ratios; 1.5, 2.0 and 2.5, and c) tree density 3.0×4.5 m, 3.0×6.0 m. Tree shape was established beginning in the 3rd leaf by summer hedging on an annual basis at the end of stage II of fruit growth. Beginning with the 4th leaf, light interception in each system was estimated by measuring the light interception below the canopy at hourly intervals after full canopy development. In 1989, yields ranged from 14,000 to 22,000 Kg ha-1. Ripening was delayed for rectangle shaped trees, with a height to clear alleyway, width ratio of 1.5, spaced 3.0×4.5 m, likely because hedging reduced leaf to fruit ratios. Within a tree form, yield was linearly related to % light interception, however rectangular trees were more productive than triangle shaped trees. The relevance of this study to orchard design will be discussed.

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Sharda, Ajay, Manoj Karkee, Gwen Hoheisel, Qin Zhang et Devin Mangus. « Design and Evaluation of Solid Set Canopy Delivery System for Spray Application in High-density Apple Orchards ». Applied Engineering in Agriculture 35, n^o 5 (2019) : 751–57. http://dx.doi.org/10.13031/aea.12512.

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Abstract. Permanent or solid set canopy delivery (SSCD) system with certain types of emitters placed along the tree rows have shown promise in the past for foliar application in tree fruit orchards. However, limited knowledge exists in terms of designing a SSCD system for uniform canopy spray coverage in tree fruit orchards. This study examined the spray coverage in high-density, super spindle apple orchards created by different nozzles and their configuration within a canopy on a SSCD system. Three different types of emitters (sprinkler, full cone, and hollow cone) and two different design configurations were evaluated in the orchard using three consecutive tree fruit rows that were 9 m long. Application pressures were 241, 379, and 517 kPa. Coverage analysis on the upper- and under-side of leaves was determined using water sensitive cards (WSC) on three randomly selected trees (23= cards/tree). The results indicated that the design configuration with two 80° hollow-cone nozzles, installed at three different canopy heights, and spray application pressure of 379 kPa provided greater coverage on upper-side (87%) and on the under-side (50%) of tree leaves. Additional studies would have to be conducted for other fruit crops and training systems to optimize system design for intended spray coverage. Keywords: Application pressure, Emitter, Solid set canopy delivery, Spray nozzle, Spray coverage.

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Howitt, Angus J., et Alan R. Hays. « Pear, Full Season Psylla Block Test, 1985 ». Insecticide and Acaricide Tests 11, n^o 1 (1 janvier 1986) : 71. http://dx.doi.org/10.1093/iat/11.1.71a.

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Abstract Treatments consisted of unreplicated 0.25 acre blocks. Materials were applied dilute by handgun on 7 May, 12 Jun, 17 Jul and 21 Aug 1985. At each sample period 50 leaves were randomly sampled from each of 4 centrally located trees in each block. A subsample of 25 leaves were examined for psylla nymphs using a stereo microscope. All 50 leaves were then brushed in a mite brushing machine and numbers of RM recorded for 8 sections. For sooty fungus a rating system was developed which included a numeric indicator of the amount of fungus present. 50 leaves were randomly selected from the same trees used above and rated as 1 (no sooty fungus), 2 (sooty fungus just visible), 3 (moderate fungus showing but less than 50% of leaf affected), 4 (severe fungus on greater than 50% of leaf). The mean sum per tree for the four trees sampled in each block is shown below.

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Andrews, J. D. « Optimal Safety System Design Using Fault Tree Analysis ». Proceedings of the Institution of Mechanical Engineers, Part E : Journal of Process Mechanical Engineering 208, n^o 2 (août 1994) : 123–31. http://dx.doi.org/10.1243/pime_proc_1994_208_218_02.

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This paper describes a design optimization scheme for systems that require a high likelihood of functioning on demand. The final design specification is achieved by solving a sequence of optimization problems. Each of these problems is defined by assuming some form of the objective function and specifying a sub-region of the design space over which this function will be representative of the system unavailability. An example of a high-pressure protection system has been used to demonstrate the practicality of the technique. Design parameters for this system include redundancy levels, the number of elements required for a voting system to function, component selection options and maintenance inspection intervals. Both implicit and explicit constraint forms have been used in the example. The implicit constraints require a full system analysis to determine whether the current design is feasible or not. All system assessments have been carried out using fault tree analysis.

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Veron, V., H. Caron et B. Degen. « Gene flow and mating system of the tropical tree Sextonia rubra ». Silvae Genetica 54, n^o 1-6 (1 décembre 2005) : 275–80. http://dx.doi.org/10.1515/sg-2005-0040.

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Abstract In this paper we report a study of the mating system and gene flow of Sextonia rubra, a hermaphroditic, insect pollinated tropical tree species with a geographic distribution in the Guyana Plateau and the Amazon. Using five microsatellites we analysed 428 seeds of 27 open pollinated families at the experimental site “Paracou” in French Guiana. We observed, compared to other tropical tree species, a high level of genetic diversity. We estimated parameters of the mating system and gene flow by using the mixed mating model and the TwoGener approach. The estimated multilocus outcrossing rate, tm, was 0.992 indicating nearly complete outcrossing. A significant level of biparental inbreeding and a small proportion of full-sibs were estimated for the 27 seed arrays. The differentiation of allelic frequencies among the pollen pools was ΦFT = 0.061. We estimated mean pollen dispersal distances between 65 m and 89 m according to the dispersal models used. The joint estimation of pollen dispersal and density of reproductive trees gave an effective density estimate of 2.1-2.2 trees/ha.

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Song, Jian Hua, Zheng Wang et Xing Dong Zhu. « Training Equipment Design for Repairing Aircraft Fuel System Based on CAN Bus ». Applied Mechanics and Materials 391 (septembre 2013) : 123–26. http://dx.doi.org/10.4028/www.scientific.net/amm.391.123.

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At this time training equipment for maintenance personnel is relatively primitive. This laboratory training equipment was designed on CAN bus and simulates a real aircraft fuel system. The device adopts the application program and KingView to build a man-machine interface and presentation, using PLC technology to achieve electrical logic control. It simulates physical device faults using CAN bus to deliver communication between industrial computer, PLC and other components. The fault tree in the form of the case is stored in the SQL database. The equipment combines software and hardware, with full functions, high stability and support for expansion. It meets fully the current training tasks and requirements for fault analysis. After testing, it has proven to be satisfactory.

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Weinbaum, S. A., F. J. A. Niederholzer, S. Ponchner, R. C. Rosecrance, R. M. Carlson, A. C. Whittlesey et T. T. Muraoka. « Nutrient Uptake by Cropping and Defruited Field-grown `French' Prune Trees ». Journal of the American Society for Horticultural Science 119, n^o 5 (septembre 1994) : 925–30. http://dx.doi.org/10.21273/jashs.119.5.925.

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Four adjacent heavily cropping 12-year-old `Petite d'Agen' prune (Prunus domestica L.) trees were selected, and two of the trees were defruited in late spring (28 May) after the spring growth flush and full leaf expansion. Trees received K daily through the drip-irrigation system, and 15N-depleted (NH4)2SO4 was applied twice between the dates of defruiting and fruit maturation. Trees were excavated at the time of fruit maturity (28 July) and fractionated into their component parts. The following determinations were made after tree excavation and sample processing: tree dry weight, dry weight distribution among the various tree fractions (fruit, leaves, roots, trunk, and branches), tree nutrient contents, within-tree nutrient distribution, total nonstructural carbohydrates (TNCs), and recovery of labeled N. Trees only recovered ≈3% of the isotopically labeled fertilizer N over the 6-week experimental period. Heavily cropping trees absorbed ≈9 g more K per tree (17% of total tree K content) during the 2-month period of stage III fruit growth than defruited trees. The enhanced K uptake in heavily cropping trees was apparently conditioned by the large fruit K demand and occurred despite greatly reduced levels of starch and TNCs relative to defruited trees. Fruit K accumulation in heavily cropping trees was accompanied by K depletion from leaves and perennial tree parts. Except for K, fruited and defruited trees did not differ in nutrient content.

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Shan, Bao Tang, et Yu Sheng Wang. « Presentation, Implementation and Application of a High Speed Hamming Distance Generator ». Applied Mechanics and Materials 128-129 (octobre 2011) : 956–60. http://dx.doi.org/10.4028/www.scientific.net/amm.128-129.956.

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To save resources and improve speed of the frame synchronization system, one resources-saving, high speed and robust hamming distance generator design method, i.e., bit-integrated full stream line wallace tree method, is presented. By contrast studies with bit-extended wallace tree method, whose performance is better than the others’ in several documents, our method not only saves resources obviously, but also can work on higher data rate. Bit-integrated full stream line wallace tree method is implemented and simulated on FPGA. Finally, it is used in a high speed frame synchronization circuit of a satellite communication system.

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Mandava, Srihari, Vanishree J et Ramesh V. « A Spanning Tree Approach in Placing Multi-channel and Minimum Channel PMU’s for Power System Observability ». International Journal of Electrical and Computer Engineering (IJECE) 5, n^o 3 (1 juin 2015) : 518. http://dx.doi.org/10.11591/ijece.v5i3.pp518-524.

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Synchronized phasor measurements have become the measurement technique of choice for electric power systems. They provide positive sequence voltage and current measurements synchronized to within a microsecond. The objective is to use the spanning tree approach and tree search technique for optimal placement of multichannel and minimum channel synchronized phasor measurement units (PMUs) in order to have full observability of Power System. The novel concept of depth of observability is used and its impact on the number of PMU placements is explained. The spanning tree approach is used for the power system graphs and a tree search technique is used for finding the optimal location of PMUs. This is tested on IEEE-14 and IEEE-30 bus system. The same technique is modified to optimally place minimum channel PMUs on the same IEEE-14 and IEEE-30 bus systems. Matlab tool has been used for fulfilling the objective.

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Allen, Ray A., et Curt R. Rom. « Light Distribution in Three Apple Training Systems as Affected by Cultivar and Rootstock ». HortScience 33, n^o 4 (juillet 1998) : 601a—601. http://dx.doi.org/10.21273/hortsci.33.4.601a.

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Light distribution in two cultivars on three dwarfing rootstocks in three high-density apple tree training systems was measured in the sixth leaf beginning at full bloom and continuing through the season. Training system had a significant effect on light penetration into the lowest point of the canopy (measured at 0.5 m), with the slender spindle being significantly darker than either the central leader or the vertical axis, although all three systems were below the threshold value of 30% full sun (FS) needed to maintain productivity for most of the season. Cultivar had no significant effect; however, trees of both `Jonagold' and `Empire' fell below 20% FS early in the season and remained there until late in the season. Rootstock had the greatest effect, with trees on M9 and M26 being significantly darker in the lower canopy than trees on Mark. Trees on M26 and M9 fell below 10% FS early in the season and remained there, while trees on Mark never fell below 20% FS.

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Subramanian, Balakrishnan, Shenghan Gao, Martin J. Lercher, Songnian Hu et Wei-Hua Chen. « Evolview v3 : a webserver for visualization, annotation, and management of phylogenetic trees ». Nucleic Acids Research 47, W1 (22 mai 2019) : W270—W275. http://dx.doi.org/10.1093/nar/gkz357.

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Abstract Evolview is an interactive tree visualization tool designed to help researchers in visualizing phylogenetic trees and in annotating these with additional information. It offers the user with a platform to upload trees in most common tree formats, such as Newick/Phylip, Nexus, Nhx and PhyloXML, and provides a range of visualization options, using fifteen types of custom annotation datasets. The new version of Evolview was designed to provide simple tree uploads, manipulation and viewing options with additional annotation types. The ‘dataset system’ used for visualizing tree information has evolved substantially from the previous version, and the user can draw on a wide range of additional example visualizations. Developments since the last public release include a complete redesign of the user interface, new annotation dataset types, additional tree visualization styles, full-text search of the documentation, and some backend updates. The project management aspect of Evolview was also updated, with a unified approach to tree and project management and sharing. Evolview is freely available at: https://www.evolgenius.info/evolview/.

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Zhang, Yaguang, James V. Krogmeier, Aaron Ault et Dennis Buckmaster. « APT3 : Automated Product Traceability Trees Generated from GPS Tracks ». Transactions of the ASABE 63, n^o 3 (2020) : 571–82. http://dx.doi.org/10.13031/trans.13384.

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Abstract. With increasing concerns about food safety in many countries, product traceability has become an important risk-management tool. It enables the identification of possible sources of defective goods and facilitates the withdrawal and recall of affected products to protect consumers from foodborne diseases. However, it is troublesome for farmers to maintain the records required by high-precision product traceability during harvesting because traditional traceability systems usually involve human labor in paperwork or expenses for equipment purchase and installation; in either case, the resulting records are tedious. In this article, a fully automatic algorithm is proposed for efficiently generating product traceability trees to visualize and store the full transport record of wheat from fields to elevators. Extending previous work on harvesting activity recognition via GPS tracks, this algorithm powers our fully automatic prototype product traceability system, APT3, and demonstrates great potential for tracing products solely with the GPS logs of the vehicles involved in harvest and transport. From the output traceability trees, the product yielded at any point in the field can be tracked all the way to the elevator where it was sold or stored by starting from the corresponding leaf node in the traceability tree and walking to the root of the tree. Furthermore, each truckload of product unloaded at any destination elevator can be traced back to where the product was harvested by following the tree in the opposite direction. In this way, the traceability records can be clearly visualized for farmers and easily used by other algorithms. Keywords: GPS, Harvesting, Precision agriculture, Product traceability, Traceability trees.

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MacCaull, Wendy. « Relational semantics and a relational proof system for full Lambek calculus ». Journal of Symbolic Logic 63, n^o 2 (juin 1998) : 623–37. http://dx.doi.org/10.2307/2586855.

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AbstractIn this paper we give relational semantics and an accompanying relational proof theory for full Lambek calculus (a sequent calculus which we denote by FL). We start with the Kripke semantics for FL as discussed in [11] and develop a second Kripke-style semantics, RelKripke semantics, as a bridge to relational semantics. The RelKripke semantics consists of a set with two distinguished elements, two ternary relations and a list of conditions on the relations. It is accompanied by a Kripke-style valuation system analogous to that in [11]. Soundness and completeness theorems with respect to FL hold for RelKripke models. Then, in the spirit of the work of Orlowska [14], [15], and Buszkowski and Orlowska [3], we develop relational logic RFL. The adjective relational is used to emphasize the fact that RFL has a semantics wherein formulas are interpreted as relations. We prove that a sequent Γ → α in FL is provable if and only if a translation, t(γ1 ● … ● γn ⊃ α)ευu, has a cut-complete fundamental proof tree. This result is constructive: that is, if a cut-complete proof tree for t(γ1 ● … ● γn ⊃ α)ευu is not fundamental, we can use the failed proof search to build a relational countermodel for t(γ1 ● … ● γn ⊃ α)ευu and from this, build a RelKripke countermodel for γ1 ● … ● γn ⊃ α. These results allow us to add FL, the basic substructural logic, to the list of those logics of importance in computer science with a relational proof theory.

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Vieira Junior, Nilson Aparecido, Marcelo Augusto de Aguiar e. Silva, Paulo Henrique Caramori, Pablo Ricardo Nitsche, Karlmer Abel Bueno Corrêa et Daniel Soares Alves. « Temperature, thermal comfort, and animal ingestion behavior in a silvopastoral system ». Semina : Ciências Agrárias 40, n^o 1 (15 février 2019) : 403. http://dx.doi.org/10.5433/1679-0359.2019v40n1p403.

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Thermal discomfort is one of the main causes of production losses in animals fully exposed to solar radiation under extensive livestock farming. The inclusion of trees in this farming system is the most efficient strategy to decrease the temperature and increase animal productivity without the need to explore new areas. In this context, the objective of this study was to characterize the microclimate in a silvopastoral system (SPS), a refuge area, and an open pasture, and evaluate thermal comfort and the ingestive behavior of animals under shade. The study was conducted at the Agronomic Institute of Paraná (IAPAR), located in Ibiporã, Paraná state, Brazil, in three areas with distinct management systems: a SPS of Eucalyptus grandis with Tifton 85 (Cynodon spp.), a woodland of Leucena leucocephala that provided shade to cattle, and a pasture in full sun (PFS). Automatic meteorological stations were installed in the SPS (one station beside the tree lines and the other in an average distance perpendicular to the rows), one in the refuge area, and one in the PFS. The measured variables were air temperature and relative humidity. The mean temperatures of the shaded treatments were compared to those of the PFS using a t-test. The mean values of the temperature and humidity index (THI) were calculated for each season of the year. The animal ingestion behavior in the SPS was analyzed in three typical days in different seasons of the year. Significant differences were observed between shade treatments and full-sun pasture, with a temperature decrease ranging from 0.4 to 1.6 °C in the shaded systems. The comparison of animal thermal comfort between the study areas in different seasons of the year indicated that there were no significant differences in thermal comfort between the SPS and refuge area relative to the PFS, suggesting a need to monitor the animals’ body temperature to better estimate thermal comfort. The evaluation of the ingestive behavior evidenced the animals’ preference to perform activities under tree shade and that the SPS led to changes in their food habits, optimizing grazing time. Therefore, the trees directly affected the microclimate of the studied environments, attenuating the temperature, protecting the animals against direct solar radiation, and providing better thermal comfort.

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Guan, Ming Jie, Xue Dong Tian, Fang Yang et Song Qiang Yang. « A Mathematical Formula Retrieval Method Using Structure Sub-Tree ». Advanced Materials Research 756-759 (septembre 2013) : 2840–45. http://dx.doi.org/10.4028/www.scientific.net/amr.756-759.2840.

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It is quite inadequate in providing formula retrieval function by traditional retrieval techniques used in full-text information retrieval system. The main reason is that there are many difficulties to extract the keywords of the mathematical formulas. In this paper, a detailed analysis of the structural characteristics of mathematical formulas and existing index mechanism of mathematical formula searching engine is fulfilled. Then a full-text index (named SLIndex) of mathematical formulas with B+ tree structure is designed and implemented which extracts the structured logic sub-tree feature as keywords of formulas and employs inverted index. Finally, a formula search engine model based on SLIndex is implemented in Apache 2.0 web server.

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Hernández Tovar, Mario Alberto, Efrén Hernández-Álvarez, Agustín Gallegos Rodríguez, Carlos M. Guzmán Paredes et Vincenzo Bertolin. « Modelo de inventario para el manejo del arbolado urbano empleando un sistema de información geográfica ». e-CUCBA 9, n^o 17 (29 décembre 2021) : 211–21. http://dx.doi.org/10.32870/ecucba.vi17.228.

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The urban trees of the Chapultepec Country neighborhood in Guadalajara, Jalisco were studied in order to elaborate a forestmanagement model and through a Geographic Information System. The neighbourhood has a total amount of 32 blocks, 1 raisedmedian, 1 roundabout, 1 park, 1 traffic easement, with a surfae area of 49.95 hectares. A full census of the wooded area wasconducted and supported by thematic mapping, data gathering of enviromental and forestry variables, using a GPS Garmin eTrex 10every tree was georeferenced. Outstandig results; there are 1386 trees, from 81 different species that belong to 31 botanical families.The more prolific are Ficus benjamina, Thuja orientalis, Arecastrum romanzoffianum, Citrus aurantium y Cupressus sempervirens.The present condition of the regsstered trees revealed that 33.91% are healthy, 57.07% are in regular condition, 7.36% are in poorcondition and 1.66% are standing dead. On the basis of the elaborated database, the wooded area census thah includes forestryvariables, pruning necessities, phytosanitary condition of the trees and thematic cartography of the wooded areas status, a forestrymanagement program was developed specially for the urban trees of the neighbourhood that can be executed weekly or monthly bythe Park and Gardens brigades. A ratio of 9.16 mgreen area surface per citizen was found, this constitutes the minimum standardrecommended by the World Health Organization (WHO). There is a relationship of 3.03 trees per habitant, a much bigger amountthan the WHO’s standard, which points out that in order to obtain a better air quality in urban areas there must be a tree for everythree citizens.

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Wadt, L. H. O., A. B. Baldoni, V. S. Silva, T. Campos, K. Martins, V. C. R. Azevedo, L. R. Mata et al. « Mating system variation among populations, individuals and within and among fruits in Bertholletia excelsa ». Silvae Genetica 64, n^o 1-6 (1 décembre 2015) : 248–59. http://dx.doi.org/10.1515/sg-2015-0023.

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AbstractThe aim of this study was to investigate variation in mating system among three Brazilian Amazon populations of the tree Bertholletia excelsa with different levels of anthropogenic interventions. We collected open-pollinated seeds from one natural population, remnant trees dispersed in a pasture, and trees from a plantation. Outcrossing rate not varied among the populations and indicates that all seeds were originated from outcrossing (tm=1.0). Mating among relatives was significant higher in the plantation than forest and pasture populations, probably due the fact that many trees are related in the plantation. Correlated mating was significantly higher in pasture (rp=0.47) and plantation (rp=0.51) than in the natural population (rp=0.22), suggesting that trees in natural population are pollinated by a higher number of pollen donors. The paternity correlation was significantly higher within (rp(w)=0.41) than among fruits (rp(a)=0.18), showing a higher probability to find full-sibs within than among fruits. The fixation index was generally lower in seed trees than in their seedlings, suggesting selection for heterozygous individuals from seedling to adult stages. Progeny arrays collected from the natural population had a lower proportion of pairwise full-sibs than in pasture and plantation and higher variance effective size (2.75) than trees in pasture (2.15) and plantations (2.22). Results highlight that seed collections for conservation, breeding and reforestation programs preferentially should be carried out in natural populations due low proportion highest variance effective size within progeny.

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Riedel, Judith, Nora Kägi, Laura Armengot et Monika Schneider. « Effects of rehabilitation pruning and agroforestry on cacao tree development and yield in an older full-sun plantation ». Experimental Agriculture 55, n^o 6 (6 février 2019) : 849–65. http://dx.doi.org/10.1017/s0014479718000431.

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AbstractOveraged full-sun cacao plantations and the need for sustainable production systems call for combining rehabilitation of plantations with the establishment of agroforestry. We tested the effect of drastic rehabilitation pruning of old cacao tree stock and the introduction of both high- and low-diversity agroforestry on survival, growth and yield of T. cacao in a commercial plantation in peninsular Malaysia over a period of 5 years. We further determined the incidence of pests and diseases of cacao pods and assessed the performance of the whole system for smallholder farmers, including yields of by-crops. Rehabilitation pruning negatively affected cacao tree development and short-term yield. No more effects of pruning on cacao yield were observed starting in the third year on in the monoculture and starting in the fourth year on in low-diversity agroforestry. We found similar cacao tree development and yield in the low-diversity agroforestry and a common practice monoculture, suggesting that the implementation of agroforestry is a commercially feasible strategy, due to additional income generated through timber production. Reduced cacao tree development and yield in the high-diversity agroforestry were compensated by additional harvests of cassava and banana compared to monoculture. Incidence of cocoa pod borer (Conopomorpha cramerella) was lower in the agroforestry systems, especially the high-diversity system, while the incidence of black pod disease (Phytophthora spp.) did not differ between agroforestry and monoculture. The findings highlight the potential of agroforestry to reconcile ecologically sustainable land use with natural, cost-effective pest management. While pruning needs to be done with timing and disease pressure in mind to minimize short-term yield losses, this measure proved to be a feasible strategy for establishing agroforestry on extant plantations.

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Yuwalee Unpaprom, Nuttapong Saetang et Sawitree Tipnee. « Evaluation of mango, longan and lychee trees pruning leaves for the production of biogas via anaerobic fermentation ». Maejo International Journal of Energy and Environmental Communication 1, n^o 3 (15 octobre 2019) : 20–26. http://dx.doi.org/10.54279/mijeec.v1i3.244925.

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Pruning fruit trees is improving their full health and harvest. Fruit tree pruning leaves waste to represent an abundant amount of organic materials, and these produced during a short period. The basic fuel properties of lignocellulosic biomass from orchards were evaluated on the following fruit tree leaves obtained from pruning operations. Biomass has become a vital source of renewable energy. Biogas is one the renewable energy which can be produced by anaerobic fermentation of biomass. In this study, mango, longan and lychee trees pruning leaves waste was utilized for biogas production. These leaves were examined on proximate analysis and ultimate analysis contents are considered as carbon (C), hydrogen (H), oxygen (O), nitrogen (N) and sulfur (S). In this study, pretreatment was performed using a sodium hydroxide solution (w/v) at different concentrations as above (1, 2, 3, and 4%). For the best feedstock screening, the theoretical biochemical methane potential was confirmed. Mango leaves biomethane content was higher compared to longan and lychee leaves. Finally, this biomass was suggested further large-scale studies. Digestate from biogas system is a highly valuable nutrient and rich fertilizer.

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Wu, Xianwei, David Jeff Jackson et Hui-Chuan Chen. « Novel fractal image-encoding algorithm based on a full-binary-tree searchless iterated function system ». Optical Engineering 44, n^o 10 (2005) : 107002. http://dx.doi.org/10.1117/1.2076828.

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Chew, Yee Jian, Shih Yin Ooi, Kok-Seng Wong, Ying Han Pang et Nicholas Lee. « Adoption of IP Truncation in a Privacy-Based Decision Tree Pruning Design : A Case Study in Network Intrusion Detection System ». Electronics 11, n^o 5 (4 mars 2022) : 805. http://dx.doi.org/10.3390/electronics11050805.

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A decision tree is a transparent model where the rules are visible and can represent the logic of classification. However, this structure might allow attackers to infer confidential information if the rules carry some sensitive information. Thus, a tree pruning methodology based on an IP truncation anonymisation scheme is proposed in this paper to prune the real IP addresses. However, the possible drawback of carelessly designed tree pruning might degrade the performance of the original tree as some information is intentionally opted out for the tree’s consideration. In this work, the 6-percent-GureKDDCup’99, full-version-GureKDDCup’99, UNSW-NB15, and CIDDS-001 datasets are used to evaluate the performance of the proposed pruning method. The results are also compared to the original unpruned tree model to observe its tolerance and trade-off. The tree model adopted in this work is the C4.5 tree. The findings from our empirical results are very encouraging and spell two main advantages: the sensitive IP addresses can be “pruned” (hidden) throughout the classification process to prevent any potential user profiling, and the number of nodes in the tree is tremendously reduced to make the rule interpretation possible while maintaining the classification accuracy.

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Yan, Fei, Wei Wei Guo, Zhong Ke Feng, Meng Lei Cao et Lu Lu Wu. « Study on Automation Technology and Method of Forest Measurement in Fixed Sample Based on Total Station and PDA ». Key Engineering Materials 467-469 (février 2011) : 1852–57. http://dx.doi.org/10.4028/www.scientific.net/kem.467-469.1852.

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In modern forest measurement situation that lack of good accuracy, in order to meet the needs of precision forestry and realize the precise measurement of every single tree, this paper introduces an automate technology and software platform of forest measurement in fixed sample. This technology and method can give full play to the precision total station angle measurement range function and PDA data processing and storage function, which are based on the communication system programming development of total station and PDA with WinCE. This automation technology are used to gain 3d coordinate, tree height, DBH and crown of trunks, it can both realize the automation process of testing trees and ensure the accuracy of measurement, improving the work efficiency greatly.

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Zhang, Shi Wei, Wen Sheng Liang et Zhi Jun Zhang. « Study on the Control System of an Automatic Testing Equipment for Diffusion Vacuum Pumps by Fault Tree Analysis ». Advanced Materials Research 118-120 (juin 2010) : 556–60. http://dx.doi.org/10.4028/www.scientific.net/amr.118-120.556.

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In order to promote the performance measurement technique of the diffusion vacuum pumps, one full-automatic test equipment was newly developed and patented. The control system is the core of the test equipment and its reliability analysis is necessary. The structure and the characteristics of the test equipment are introduced in paper. The fault tree of the test equipment is set up and illustrated in detail. Based on fault tree analysis, the reliability designs of the hardware and software of the test equipment are carried out.

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Huang, Guangshun. « Intelligent Campus Resource Sharing System Based on Data Fusion Sensor ». Journal of Sensors 2022 (4 juillet 2022) : 1–7. http://dx.doi.org/10.1155/2022/4814727.

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In order to make full use of the large amount of teaching data existing in the data center, the author proposes a mining algorithm using classification technology and association rules in data mining technology; the teaching quality evaluation data and student achievement data were mined. By constructing the C4.5 decision tree algorithm, this method taps the potential links between teachers’ professional titles, degrees, ages, and teaching quality evaluation results, through correlation analysis theory; the correlation between professional courses was mined from the student’s course achievement database, and some reasonable and reliable course association rules were obtained. Experimental results show that the correct rate of C4.5 decision tree algorithm under different sampling times is above 80%. The conclusions drawn have certain guiding significance for college teaching and personnel training.

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Mousavi, R., M. Nikooy, E. NezhadA et M. Ershadfar. « Evaluation of full tree skidding by HSM-904 skidder in patch cutting of aspen plantation in Northern Iran ». Journal of Forest Science 58, No. 2 (21 février 2012) : 79–87. http://dx.doi.org/10.17221/78/2011-jfs.

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This paper presents research results of the performance of HSM-904 grapple skidder using a full tree harvesting method in a non-native aspen Populus deltoides plantation in even terrain conditions in Shafaroud, Northern Iran. Patch cutting as a silvicultural method was used in the plantation (2,000 ha). To evaluate the newly introduced machine to a ground skidding system in the aspen plantation and the possibility to increase the production rate, an empirical time study was conducted. The elements of the skidding work phase were identified and 58 cycles were recorded for the study. The models for effective time consumption, total productivity and work phase models are calculated. The average load per cycle was 2.2 m3, the average one-way skidding distance was 253 m. The average travel speed of unloaded skidder was 5.53 km·h-1 and the average speed of loaded skidder was lower than the speed of the unloaded one by 2.94 km·h-1. The average output in the study was 7.1 m3 per effective hour and the unit cost was 13.9 USD·m-3.

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Britto, Pedro C., Dirk Jaeger, Stephan Hoffmann, Renato C. G. Robert, Alexander C. Vibrans et Alfredo C. Fantini. « Impact Assessment of Timber Harvesting Operations for Enhancing Sustainable Management in a Secondary Atlantic Forest ». Sustainability 11, n^o 22 (8 novembre 2019) : 6272. http://dx.doi.org/10.3390/su11226272.

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Conservation and management of forest ecosystems are currently largely conflicting goals in the Brazilian Atlantic Forest biome. At present, all parts of the Atlantic Forest are protected and commercial logging is highly restricted. However, sustainable forest management systems can offer significant income opportunities for landholders, and thereby actively support the process of ecosystem rehabilitation and protection of the Atlantic Forest. This research is intended to contribute to enhancing the development of environmentally sound forest management alternatives in the Atlantic Forest biome. Through a case study, the harvesting impact of a conventional harvesting method (CM) was evaluated and compared with an alternative and improved harvesting method (AM), performed by a well-trained professional chainsaw operator experienced in reduced impact logging techniques, and included the use of a snatch block and a skidding cone. Following a full pre-harvest inventory, 110 different tree species were identified. The harvesting impact on the residual stand was classified and evaluated through a successive post-harvest inventory. Damage maps were developed based on interpolation of tree damage intensities with the triangular irregular networks (TIN) methodology. Our results showed noticeable high rates of tree hang-ups, observed for both harvesting methods. Furthermore, the harvesting damaged trees mainly in the lower diameter at breast height (DBH) classes. In comparison to winching, the felling process caused most of the damage to remnant trees for both methods, at 87% (CM) and 88% (AM). The number of damaged trees (above 11.9 cm DBH) per harvested tree, for CM, ranged from 0.8 trees to 2.5 trees and, for AM, ranged from 0.6 trees to 2.2 trees. Improvements of the AM method (operator skills, skidding cone and snatch block) over CM allowed for a reduction of the damaged basal area, a reduction of the “high damaged area” per plot, and a reduction of the winching disturbed ground area. Nonetheless, a suitable harvesting system should consider further improvements in the felling technique, and additionally integrate the local knowledge of CM regarding forest and tree species with the technical improvements of AM.

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Alarfaj, Maryam, et Chris Sangwin. « Updating STACK Potential Response Trees Based on Separated Concerns ». International Journal of Emerging Technologies in Learning (iJET) 17, n^o 23 (8 décembre 2022) : 94–102. http://dx.doi.org/10.3991/ijet.v17i23.35929.

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The STACK system is a computer aided assessment package for mathematics. STACK questions include full algebraic input with validation. Feedback is provided to students using "potential response trees", written by the teacher for each question. In this research, we are updating STACK potential response tree based on students' concerns in learning induction proofs. We have identified a specific misconception in learning mathematical induction from prior educational research, designed STACK question to test if students exhibit this misconception, and then illustrated how we updated STACK potential response tree based on this misconception. One main goal of separating concerns is to understand students’ responses and evaluate the question itself from an academic prospective and ultimately to improve the questions for future years. In addition, one of the contributions of this study is to improve our general understanding of how to design and use STACK potential response trees.

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Rubauskis, Edgars, Māra Skrīvele, Silvija Ruisa et Daina Feldmane. « Effect of Crown Restriction on the Growth and Productivity of Sweet Cherries ». Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences 67, n^o 2 (1 août 2013) : 151–56. http://dx.doi.org/10.2478/prolas-2013-0023.

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The canopy of sweet cherry trees grown under cover has to be adapted to this growing system by canopy lowering, narrowing and renewing. Tree growth and productivity parameters were compared three years before and three years after canopy restriction (2006-2011) for cultivars ‘Iputj’ and ‘Krupnoplodnaya’ on rootstocks Gisela 4 and 5, Weiroot 154 and F 12/1 during the full production period. The largest trees with wider canopy both before and after canopy restriction were observed on rootstock F 12/1. Limiting pruning of trees on Weiroot 154 did not cause stronger shoot growth. On Weiroot 154 the canopy was slightly bigger than for trees on Gisela 4 and 5. Canopy volume was bigger for ‘Iputj’ before adaptation to the cover system than for ‘Krupnoplodnaya’. After canopy reduction the fruiting wood renewed slowly, and therefore, yield per tree even in the third year after pruning was almost three times less than before pruning. As cultivar ‘Krupnoplodnaya’ renewed fruiting wood faster, it was 5-37% more productive than ‘Iputj’. Productivity renewed more rapidly for trees on dwarfing rootstocks, especially on Gisela 5. The fruits of cultivar ‘Krupnoplodnaya’ were bigger both before and after pruning compared with ‘Iputj’. Of the tested rootstocks, F 12/1 was found to be not suitable for plantations under cover.

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Ferdush, Jannatul, Md Meftahul Karim, Iffat Jahan Noor, Sadia Afrin Sadia Afrin Ju, Tofayel Ahamed et Dr Sataya Ranjan Saha. « Impact of alley cropping system on soil fertility ». International Journal of Advanced Geosciences 7, n^o 2 (17 novembre 2019) : 173. http://dx.doi.org/10.14419/ijag.v7i2.29942.

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A field experiment was conducted to investigate the effect of pruned materials of two hedgerow species on wheat production and soil nutrient changes at different nitrogen levels in the research farm of the Bangabandhu Shiekh Mujibur Rahman Agricultural University (BSMARU) during November 2012 to March 2013. The design of the experiment was split plot, where two multipurpose tree species (MPTS) namely Gliricidia sepium and Leucaena leucocephala were arranged in main plots and five different doses of nitrogen (0, 25, 50, 75 and 100 % of recommended dose) with pruned materials were distributed to sub plots. Alley widths of both tree species were 6.0 meter. There were also control plots where full dose of recommended nitrogen was applied but no pruned material (PM) was incorporated. The soil chemical properties in the alleys consisting of G. sepium and L. leucocephala responded differently. Positive changes in the soil fertility in terms of soil pH, organic C, total N, available P, available S and exchangeable Ca, Mg, K and CEC of the top soil layer were observed in alley cropping system. Pruned materials application substantially reduced the nitrogen requirement for wheat production and 50 % Nitrogen fertilizer could be saved through pruned materials application. Among the tree species G. sepium seemed to be superior over L. leucocephala in building soil health.

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Jérémie, Gala Bi Trazié, Bohoussou N’Dri Yves, Akotto Odi Faustin et Yao-Kouamé Albert. « Impact Des Arbres Associés Sur L’exploitation Cacaoyère Dans Les Zones De Transition ForêtSavane : Cas De M’Brimbo (Centre-Sud De La Côte d’Ivoire) ». European Scientific Journal, ESJ 13, n^o 1 (31 janvier 2017) : 164. http://dx.doi.org/10.19044/esj.2017.v13n1p164.

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Despite its status as the first world's cocoa producer, the cocoa production system in Côte d'Ivoire remains characterized by low yields. To solve this problem, a study was carried out on the cocoa farms of the Agricultural Society of Bandama, in southern center of Côte d'Ivoire, in the forest and savannah transition zone. It focused on determining the impact of associated forest species in cocoa farms on cocoa tree development. Thus, the associated tree species have been inventoried. The number of associated species per hectare allowed classification of the cocoa farm according to the degree of shade. From o to more than 80 trees / ha, rates of parasitic attack and mortality increase, while yield of cocoa bean decreases. For cocoa trees at the beginning of maximum yield stage (8 years old plantation), the full-sun system is more productive, with 498 kg of cocoa beans / ha. For the highest density of associated forestspecies, the yield was 127 kg / ha, with a cocoa plant success rate of 55% and a parasitic attack rate of 40%. Moreover, the parasitic attack rate of less than 20%, due to the associated trees, could lead to a reduction of almost half of the potential yield. To avoid a fall in yield and maintain the success rate at an acceptable level, in shade systems, a threshold of 25 to 30 associated trees / ha has been established. But the parasitic attacks, responsible for the drop in yield should be controlled.

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Lima, Hugo N. B., José C. B. Dubeux Jr, Mércia V. F. Santos, Alexandre C. L. Mello, Mário A. Lira, Márcio V. Cunha, Erinaldo Viana De Freitas et Valéria Xavier De Oliveira Apolinário. « Herbage responses of signalgrass under full sun or shade in a silvopasture system using tree legumes ». Agronomy Journal 112, n^o 3 (7 avril 2020) : 1839–48. http://dx.doi.org/10.1002/agj2.20137.

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Parra, Margarita, David Hortelano, Francisco García-Sánchez, Diego S. Intrigliolo et José S. Rubio-Asensio. « Effects of Drip Irrigation Design on a Lemon and a Young Persimmon Orchard in Semi-Arid Conditions ». Water 13, n^o 13 (29 juin 2021) : 1795. http://dx.doi.org/10.3390/w13131795.

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Drip irrigation is presently widely recognized as the most efficient irrigation system that can be used in woody perennial crops. However, uncertainties exist on the more appropriate agronomic design to employ. Here, we summarized the research carried out for three seasons in two young woody perennial crops (persimmon and lemon) in southeastern Spain. Several irrigation designs were compared by maintaining a similar amount of water application but varying the number of emitters and pipelines in each row in the orchard. In the lemon trial, the agronomic irrigation design was additionally combined with different irrigation regimes, comparing full irrigation (FI) with sustained deficit irrigation (SDI). In the persimmon trees, which were still at the juvenility stage, varying the number of emitters per tree or the number of drip lines per tree row, neither affects tree performance nor fruit yield in two out of the three seasons. However, over the entire experimental period, the relative trunk growth increased when more emitters were employed. In the lemon trial, carried out with trees that had reached commercial production, the FI, compared with SDI, increased trunk growth and average fruit weight, while a reduced number of fruits per tree without affecting total yield was observed in the third year of experimentation. The number of emitters per tree only had an effect the first year, increasing lemon fruit weight when the number of drippers per tree increased. In addition, fruit composition was not consistently affected by the irrigation design. It is concluded that, for a given irrigation dose, irrigation frequency, and soil conditions (loam-clay texture), in both very young and more mature trees, increasing the number of emitters or the wetted area only had some slight positive effects on tree performance.

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Kappel, Frank, et Harvey A. Quamme. « Orchard training systems influence early canopy development and light microclimate within apple tree canopies ». Canadian Journal of Plant Science 73, n^o 1 (1 janvier 1993) : 237–48. http://dx.doi.org/10.4141/cjps93-038.

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Delicious and McIntosh apple trees were trained to five orchard systems: central leader (two spacings), slender spindle, van Roechoudt trellis, and vertical axe. Radiation measurements were taken at the bottom of the canopy throughout the season or at various heights within the canopy after the growth of the canopy was completed. Early in the life of the plantings slender spindle and vertical axe trees of each cultivar had the highest yields expressed on a per hectare basis. By the fifth year of the planting, McIntosh trees trained to the slender spindle and the narrow central leader spacing were producing similar amounts of fruit. Light levels at the bottom of the canopy for some orchard systems were at or below 30% of full sun as early as 25 d after petal fall. Orchard system affected total leaf area and the number of spurs per tree in both 1989 and 1990. The low light levels at the bottom of the canopy reported in this study suggest that attention to pruning and training in the early stages of the orchard development is critical. Key words: Malus domestica, central leader, slender spindle, van Roechoudt trellis, vertical axe, light distribution, leaf area index

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Oliveira, V. A. V., T. G. S. Braz, R. B. Silva, A. C. R. Veloso, L. D. A. Rufino, J. A. Martuscello, M. H. F. Mourthé et L. V. Barros. « Defoliation heights for palisade grass cv. Marandu in silvopastoral system ». Arquivo Brasileiro de Medicina Veterinária e Zootecnia 73, n^o 3 (mai 2021) : 665–74. http://dx.doi.org/10.1590/1678-4162-12253.

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ABSTRACT The objective was to test the response of Urochloa brizantha cv. Marandu in monoculture and in silvopastoral system (SPS), at two distances from the trees, and define the best defoliation height for SPS. Four intermittent defoliation heights (25, 35, 45 and 55cm) and two distances from tree lines (2.5 and 5.0m) were evaluated in the SPS with a control defoliated with 25cm in full sun. The experiment was performed in a randomized block design with 3 replicates in a 4 × 2 + 1 split plot scheme. The control had higher forage accumulation (46.9kg/ha. day) than the SPS (31.1kg/ha. day). The bulk density was also higher in the control (0.89mg/cm³) than in SPS (0.48mg/cm³). The percentage of leaves (78.06%) and leaf/stem ratio (6.04) did not differ among the treatments. In the SPS, there was an increase of 31.07% in forage accumulation from 25 to 55cm. The forage accumulation and bulk density of Urochloa brizantha cv. Marandu in monoculture is greater than in the SPS regardless of the management goal and the distance from trees. The goal of 55cm in the SPS presented greater forage accumulation.

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ALVES, Rafael Moysés, Saulo Fabrício da Silva CHAVES, Marcos André Piedade GAMA, Jack Loureiro PEDROZA NETO et Thalita Gomes dos SANTOS. « Simultaneous selection of cupuassu tree and Brazilian mahogany genotypes in an agroforestry system in Pará state, Brazil ». Acta Amazonica 50, n^o 3 (septembre 2020) : 183–91. http://dx.doi.org/10.1590/1809-4392202000711.

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ABSTRACT This study aimed to evaluate and select progenies and matrices of cupuassu-tree siblings, and to select Brazilian mahogany matrices with superior characteristics to be used in agroforestry systems (AFS). Twenty-five full cupuassu tree sibling progenies and one Brazilian mahogany half-sibling progeny were evaluated. The study was conducted for 14 years in a commercial property in Tomé Açu, Pará State, Brazil. The number of fruits and fruit yield per plant, as well as the rate of plants with symptoms of witches’ broom disease, were used as response variables for cupuassu. For mahogany, the following response variables were used: total height, commercial height, crown height, diameter at breast height and commercial wood volume. There were five cupuassu tree progenies with interesting characteristics to be used in AFS. Based on the high values observed in the selection accuracy and heritabilities, a good potential for the selection of promising individuals in the cupuassu tree population is inferred. Based on the ranking of genotypic values and their agronomic performance, 10 matrices of cupuassu tree were selected. For Brazilian mahogany, three matrices showed excellent silvicultural performance. The matrices of these two species should be propagated vegetatively in order to evaluate clonal tests.

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