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Artykuły w czasopismach na temat "DIFFERENT SIZES OF WOODEN BLOCKS"
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Souza, Thiago Sampaio de, Vinícius Siqueira Gazal, Vinicius José Fernandes, Ana Carolina Campos de Oliveira i Elen De Lima Aguiar-Menezes. "Influence of Food Resource Size on the Foraging Behavior of Nasutitermes corniger (Motschulsky)". Sociobiology 65, nr 2 (9.07.2018): 291. http://dx.doi.org/10.13102/sociobiology.v65i2.2844.
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In general, termite foraging can be affected by physical and chemical factors linked to food. This study investigated if the wood length of Eucalyptus grandis W. Hill ex Maiden, as a food resource, influences the behavior of foraging events of Nasutitermes corniger (Motschulsky). Nests with mature and active colonies were collected in the field and transferred to glass cubes connected to a test arena under laboratory conditions. Wooden blocks of E. grandis, with a 2.5 x 2.0 cm rectangular cross section, were offered to termites in three different lengths: 5, 10 and 15 cm. Each test was repeated with 20 nests and lasted 60 minutes, when the following behavioral events and their duration were observed: initial exploration, initial recruitment and mass recruitment. At the end of each test, the quantities of termites (total, workers and soldiers) and gnawing workers were determined. The results show that longer blocks favored a higher occurrence of exploration and initial recruitment. However, the highest mass recruitment occurred with the 10 cm blocks. The length of the wood influenced the total number of termites recruited and gnawing workers; both were highest for the 10 cm blocks. There was no significant difference in relation to exploration time of the blocks and number of workers and soldiers recruited. Therefore, we conclude that wood length is a factor that can affect N. corniger foraging.
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Kamble, Zunjarrao, Rajesh Kumar Mishra, Bijoya Kumar Behera, Martin Tichý, Viktor Kolář i Miroslav Müller. "Design, Development, and Characterization of Advanced Textile Structural Hollow Composites". Polymers 13, nr 20 (14.10.2021): 3535. http://dx.doi.org/10.3390/polym13203535.
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The research is focused on the design and development of woven textile-based structural hollow composites. E-Glass and high tenacity polyester multifilament yarns were used to produce various woven constructions. Yarn produced from cotton shoddy (fibers extracted from waste textiles) was used to develop hybrid preforms. In this study, unidirectional (UD), two-dimensional (2D), and three-dimensional (3D) fabric preforms were designed and developed. Further, 3D woven spacer fabric preforms with single-layer woven cross-links having four different geometrical shapes were produced. The performance of the woven cross-linked spacer structure was compared with the sandwich structure connected with the core pile yarns (SPY). Furthermore, three different types of cotton shoddy yarn-based fabric structures were developed. The first is unidirectional (UD), the second is 2D all-waste cotton fabric, and the third is a 2D hybrid fabric with waste cotton yarn in the warp and glass multifilament yarn in the weft. The UD, 2D, and 3D woven fabric-reinforced composites were produced using the vacuum-assisted resin infusion technique. The spacer woven structures were converted to composites by inserting wooden blocks with an appropriate size and wrapped with a Teflon sheet into the hollow space before resin application. A vacuum-assisted resin infusion technique was used to produce spacer woven composites. While changing the reinforcement from chopped fibers to 3D fabric, its modulus and ductility increase substantially. It was established that the number of crossover points in the weave structures offered excellent association with the impact energy absorption and formability behavior, which are important for many applications including automobiles, wind energy, marine and aerospace. Mechanical characterization of honeycomb composites with different cell sizes, opening angles and wall lengths revealed that the specific compression energy is higher for regular honeycomb structures with smaller cell sizes and a higher number of layers, keeping constant thickness.
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Rebouças, Patricia Oliveira, Cândida Aguiar, Vinina Ferreira, Geni Sodré, Carlos Carvalho i Miriam Gimenes. "The Cavity-Nesting Bee Guild (Apoidea) in a Neotropical Sandy Coastal Plain". Sociobiology 65, nr 4 (11.10.2018): 706. http://dx.doi.org/10.13102/sociobiology.v65i4.3339.
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Some solitary bees establish their nests in preexisting cavities. Such nesting behavior facilitates the investigation of their life history, as well as the monitoring of their populations in natural, semi-natural and cropped habitats. This study aimed to evaluate the acceptance of artificial substrates by cavity-nesting bees in a heterogeneous landscape. We investigated the percentage of occupation of the different trap-nests, the monthly fluctuations in the nesting activity, offspring sex ratio, mortality and parasitism, in two phytophysiognomies: herbaceous-shrub restinga (site 1) and arboreal restinga (site 2). We used as trap-nests, bamboo canes, large and small straws of cardboard inserted into solid wooden blocks. Five bee species established 193 nests, from which 386 adults emerged. Centris tarsata Smith was the most abundant species. Large straws were signifi cantly more occupied than small straws (χ² = 19.951; df = 1; p < 0.0001). Offspring mortality rate for unknown reasons was signifi cant diff erent between sites, 11% (site 1) and 20% (site 2) (χ² = 4.203; df = 1; p = 0.04). The cavity-nesting bee guild had similar composition in both phytophysiognomies, there was a similar rate of occupation of trap-nests in both sites, as well as dominance of C. tarsata nests. Offspring mortality and parasites attack rates seem to be the more distinctive aspects between the herbaceous shrub and arboreal restinga sampled. Our study indicated that remnant fragments of coastal native habitats may be important nesting sites for the maintenance of bee populations, some of which have been indicated as candidates for management as pollinators of cultivated plants in Brazil.
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Wang, C. X., B. H. Li, X. L. Dong i G. F. Li. "First Report of Stem Canker on Cherry Caused by Phomopsis perniciosa in Shandong Peninsula, Eastern China". Plant Disease 95, nr 10 (październik 2011): 1316. http://dx.doi.org/10.1094/pdis-04-11-0341.
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Cherry is a main fruit tree species in Shandong Peninsula, which is one of the most important cherry-production areas of China. A stem canker disease was first noted in a 15-year-old cherry orchard in Yantai, Shandong Peninsula in May 2009. Canker and branch dieback were the main symptoms of the disease and cracks often appeared at the margins of sunken cankers, which exposed the wooden stem. In later stages from April to May, black pycnidia were observed on the surface of cankered bark and cirri containing α-conidia were extruded under wet conditions. Wooden tissue under the diseased bark was dark brown, in contrast to the healthy tissue that was yellowish green. On the basis of morphological characteristics, the pathogen was putatively identified as Phomopsis perniciosa (1). Pycnidia were smaller in naturally infected branches than when produced on potato dextrose agar (PDA) medium (180 to 365 × 65 to 226 μm). Cultures of the pathogen appeared creamy white with concentric rings on PDA at 25°C and a mass of α-conidia (5.75 to 11.13 × 2.08 to 3.46 μm) and β-conidia (31.24 to 34.68 × 1.45 to 1.82 μm) were produced within 3 weeks. Alpha-conidia were hyaline, fusiform-elliptic to oblong-elliptic, and biguttulate. Beta-conidia were hyaline and unicellular, filiformia, leviter arcuata vel hamata. Total DNA was extracted from three monoconidial isolates collected from different infected trees. The internal transcribed spacer (ITS) region was amplified using the universal primers ITS1 (5′-TCCGTAGGTGAACCTGCGG-3′) and ITS4 (5′-CCTCCGCTTATTGATATGC-3′). The ITS amplicons were sequenced (582 bp) from three isolates and no nucleotide variation was observed. BLAST analysis of the obtained ITS sequences showed that isolate 230101 had 99% homology with a Phomopsis sp. (GenBank Accession No. AB302248) isolated from fruit trees in Japan. The nucleotide sequence from isolate 230101 has been deposited in GenBank (Accession No. JF812647). Pathogenicity of the isolate was confirmed by inoculating branches of 3-year-old cherry trees with either conidia or hyphae. Inoculations were performed by making an incision with a sterile scalpel at the dissected area to expose the tissue under the bark. An agar plug (4 × 4 mm) containing 5-day-old cultured hyphae or 50 μl of a conidium suspension containing 106 α-conidia per ml was placed on each of the inoculation sites, wrapped with moist cheesecloth, and sealed with Parafilm. Control trees were treated similarly with sterile blocks of PDA or water, respectively. For each inoculation technique, five shoots were inoculated and the inoculation treatments were replicated three times. All inoculated and control trees were kept in a greenhouse and watered as needed. After 10 days, cankers and necrotic lesions developed on all shoots inoculated with P. perniciosa and the control trees did not display any symptoms. The same pathogen was reisolated from symptomatic branches. Phomopsis spp. are known to cause cankers and dieback of several woody hosts (2), but no reports have been found that the pathogen causes cherry canker and dieback in China. References: (1) P. K. Chi et al. Flora Fungorum Sinicorum-Phomopsis 34:127, 2007. (2) D. P. Weingartner and E. J. Klos. Phytopathology 65:105, 1975.
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Han, Xiaoli, Jian Dai, Wei Qian, Baolong Li, Yuanjun Jin i Ting Jiang. "Effect of column foot tenon on behavior of larch column base joints based on concrete plinth". BioResources 15, nr 3 (9.07.2020): 6648–67. http://dx.doi.org/10.15376/biores.15.3.6648-6667.
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The wooden columns in timber structures of ancient buildings have column foot tenons of various sizes. The main reason for these differences is their use for different roof loads. Six full-scale specimens with different sizes of column foot tenon were designed and manufactured. The tree species used for the specimens was larch. The quasi-static test was conducted on the specimens that were used in timber structures of ancient buildings. The effects of column foot tenon size on the mechanical properties of larch wooden columns were studied. The moment-rotational angle hysteretic curves, moment-rotational angle skeleton curves, ductility, stiffness degradation, energy dissipation capacity, slippages between the wooden column and the plinth, and the damage of the column foot tenons were examined. The test results showed that the column foot tenon played an important role in the mechanical behavior of the wooden column under low-cycle reversed cyclic loading. The rotation of the column foot tenon improved the energy dissipation capacity of the wooden column. As the rotational angle of the column base increased, the column foot tenon had different degrees of damage. Different sizes of column foot tenon had their own advantages and hysteretic behavior.
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Gomes, Caroline J. S., André Danderfer Filho, Ana Maria A. Posada i Anielle C. da Silva. "The role of backstop shape during inversion tectonics physical models". Anais da Academia Brasileira de Ciências 82, nr 4 (grudzień 2010): 997–1012. http://dx.doi.org/10.1590/s0001-37652010000400021.
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The style of deformation of rocks from basin-infilling sequences in positively inverted natural basins was discussed upon the results of laboratory experiments carried out in sandboxes with sand packs laid down in the space between two wooden blocks. The space simulated stages of crustal extension leading to (1) a half graben due to extension above a listric extensional detachment, with the blocks simulating the footwall and hanging wall, or (2) a graben, with the blocks simulating the external margins that drifted apart above a horizontal detachment. Combinations of two different angles were used to simulate the dip of curved normal faults along the internal face of the wooden blocks. Backstops in the half graben had a convex up internal face. Backstops in the graben had a concave up internal face. Shortening as partitioned in forward and backward movements within the sand packs, and the kinematics of contraction was largely influenced by the convex or concave internal faces. A buttress effect characterized by rotation of the sand pack close to the footwall was stronger for footwall with steeper-dipping internal faces. The results were compared to other physical experiments and applied to an inverted basin found in nature.
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Nur Hidayah, A. H., Md Nor Hasanan i P. J. Ramadhansyah. "Physical Properties of Porous Concrete Paving Blocks with Different Sizes of Coarse Aggregate". Advanced Materials Research 1113 (lipiec 2015): 86–92. http://dx.doi.org/10.4028/www.scientific.net/amr.1113.86.
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This research studies the properties of Porous Concrete Paving Blocks (PCPB) with different sizes of coarse aggregate. Coarse aggregate (CA) is the main component in manufacturing PCPB. Three different sizes of coarse aggregate were used; 1) CA 5 – 10 mm as a control, 2) CA 5 – 8 mm and 3) CA 8 – 10 mm. Furthermore, a series of test were conducted such as density, compressive strength, porosity and skid resistance test to determine the properties of the blocks. It was found that the size of coarse aggregate affects the strength and porosity of the blocks. The strength was reduced approximately in the range 5 % to 17 % from the control blocks. However, it is vice versa with porosity result which porosity of the blocks increased in between 5 % to 10 %. This shows that the blocks suitable for use in vehicle area where help in reduce the water ponding on pavement surface and also increased the skid resistance between the vehicle tires and pavement.
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İşleyen, Ümmü K., Rahim Ghoroubi, Ömer Mercimek, Özgür Anil i Recep Tuğrul Erdem. "Behavior of glulam timber beam strengthened with carbon fiber reinforced polymer strip for flexural loading". Journal of Reinforced Plastics and Composites 40, nr 17-18 (9.04.2021): 665–85. http://dx.doi.org/10.1177/0731684421997924.
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In the last 20 years, the use of wooden structures and their dimensions have gradually increased. The wood application has increased in different structures such as multistory buildings, sports, industrial facilities, road and railway bridges, power transmission lines, and towers. The widespread use and size of wood structures have increased the research on developing special types of wood products supported by composite materials. Laminated wood elements are the leading composite wood materials. Laminated wooden beams allow making much larger openings than standard solid wood structural elements. The development of the sizes and usage areas of wooden structures has increased the capacity of glulam structural elements and reveals the need to improve their performance. Carbon fiber reinforced polymers (CFRPs) are the most suitable options for increasing the bearing capacity values of glulam beams and improving general load–displacement behaviors. In this study, the use of CFRP strips in different layouts to increase glulam wooden beams and the application of CFRP fan-type anchors in the CFRP strip endpoints are the studied variables. Anchored and non-anchored glulam wooden beams reinforced with CFRP strips with different layouts were tested using a three-point bending test. The ultimate load capacity, initial stiffness, displacement ductility ratio, energy dissipation capacity, failure mechanisms, and general load–displacement behavior of wooden beam test specimens were obtained and interpreted as a result of the experiments.
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Ovsyannikov, Sergey I., i Vladislav Yurevich Dyachenko. "Wooden Nano-Composite Materials and Prospects of their Application in Wooden Housing Construction". Materials Science Forum 931 (wrzesień 2018): 583–88. http://dx.doi.org/10.4028/www.scientific.net/msf.931.583.
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Nano-composite material is a completely new class of material that combines wood pulp and some porous materials of artificial and natural origin. This is an artificially created material consisting of a polymer matrix of the porous natural or synthetic material. The number of micro or macro-pores in the composite can be different for different wood species variety of micro and macro capillaries varying in average from 25 to 35% of the wood volume. The change in wood properties occurs at the structuring of water-insoluble molecules smaller than 3 nm and that is a part of the filler. Industrial technology of deep processing of wood-based nanotechnology allows the manufacture of new products such as laminated wood structures with nano-device that have properties not existing in nature: 1. The wood becomes hydrophobic, it is characterised by almost complete lack of absorption by the body of the wood, which leads to almost full, the lack of swelling and the change of the geometrical sizes of the material; 2. The absence of cracking. As the penetrating substance is evenly distributed between micro and macro pores and uniformly fills all the frame structure, there are additional internal stresses, typical for products made of natural wood; 3. The use of such technology ensures high 10-25% of the density if you increase strength by 20%, which also increases the seismic resistance and mi CNTI products and structures.
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Antonietti, Alessandro, i Beatrice Nava. "Solution of an Insight Problem at Different Age Levels". Perceptual and Motor Skills 80, nr 3_suppl (czerwiec 1995): 1215–18. http://dx.doi.org/10.2466/pms.1995.80.3c.1215.
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The purpose was to study performance on an insight problem by 3-to 25-yr.-olds. A task involving restructuring and requiring two wooden blocks be fitted together to form a tetrahedron was presented to five groups of 20 subjects each from kindergarten, primary school, secondary school, high school, and a university. The frequencies of solvers within each group increased from the first age group to the third but then remained constant. Solution times and frequencies of solutions attempted were not significantly different among the five groups. Perhaps insight does not follow the same developmental trend as other thinking processes.
Książki na temat "DIFFERENT SIZES OF WOODEN BLOCKS"
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Co, John Watson Mfg, red. Improved field cultivator: Three levers, furnished with either steel or wooden wheels and with different widths of steels or shoes made in two sizes. Ayr, Ontario, Canada: John Watson Manufacturing Co., 1986.
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Co, John Watson Mfg, red. Improved field cultivator: Three levers, furnished with eiter steel or wooden wheels and with different widths of steels or shoes made in two sizes. Ayr, Ontario, Canada: John Watson Manufacturing Co., 1986.
Znajdź pełny tekst źródłaCzęści książek na temat "DIFFERENT SIZES OF WOODEN BLOCKS"
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Zerkal, Oleg V., i Olga S. Barykina. "Suffosion Landslides as a Specific Type of Slope Deformations in the European Part of Russia". W Progress in Landslide Research and Technology, Volume 1 Issue 2, 2022, 99–108. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-18471-0_8.
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AbstractLandslide classification systems are based on the analysis of mechanisms of slope deformation and consideration of landslide-forming earth materials. The main types of landslide movement are fall, topple, slide, spread and flow. Within the European part of Russia, a specific type of slope deformation is often observed, where suffosion (the process of washout and mechanical removal of fine particles from saturated soils under the influence of infiltrating groundwater flow) plays an essential role. Suffosion landslides are defined as a type of complex landslide formed in regions characterized by alternating horizons of unsaturated and saturated sands, loams and clays. Such hydrogeological conditions occur in the European part of Russia, most of which is occupied by the East European Plain. In the East European Plain, suffosion landslides are confined to the valleys of large rivers and their tributaries (Volga, Oka, Don, etc.), where their volumes can reach several million m3. In the Volgograd and Moscow regions, suffosion can result in soil decompaction at the base of slopes, or the formation of underground cavities in massifs, niches and grottoes on slopes, ultimately leading to the formation of suffosion landslides. Suffosion landslides are complex displacements of waterlogged soil masses formed as a result of suffosion and the subsequent associated collapse of the sides of suffosion cavities and niches. Indicators of suffosion landslides are: (1) the presence of a prograding fan of finely dispersed material at the base of slope and adjacent terrain, whose boundaries often exceed the landslide limits; and (2) a large number of ledges of different sizes on the surface of the landslide body created by uneven settling of blocks into the roof of suffosion cavities, and on the sides of suffosion niches. Suffosion landslides are often elongated, horseshoe-shaped, or ∞-shaped with a narrowing in the central part formed in saturated soils breaching from an underground suffosion cavity. Suffosion landslides do not have a marked sliding surface. Rather, soil displacement occurs over layers with strongly dispersed groundwater. The displacement rate of such landslides depends on the scale and speed of development of mechanical suffosion at the base of the slope.
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American Association for the Advancement of Science. "Curriculum Blocks". W Designs for Science Literacy: with companion CD-ROM, 123–47. Oxford University PressNew York, 2001. http://dx.doi.org/10.1093/oso/9780195132786.003.0013.
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Abstract For millennia, designers of plazas, walls, arches, bridges, and domes have used bricks as their basic construction units. Identical bricks can be arranged in a surprising number of different patterns, and many times more patterns can be created using only a few different kinds of brick. Some aspects of the patterns are essential to the purpose of the structure, whereas other aspects may be merely pleasing. To suit one purpose or another, the bricks can be different in material composition (marble, stone, glass, concrete, metal, plastic, clay, wood), structural properties (size, shape, strength, resilience, durability, response to temperature), appearance (color, transparency, surface texture), and inevitably cost (bare minimum to extravagant). How well the structure will do its basic job depends more on some of these properties than others, but any property may be important in motivating and selling the design. Obviously a designer needs to know what the properties of bricks really are and what features the final design must have. In the 20th century, sad to report, curriculum designers have not been so well blessed. For most of the century, they have had only a few kinds of “bricks” available to them, and those in only two “shapes”—one period, five days a week for one semester and one period, five days a week for one year. To make matters worse, there simply is no agreed-upon set of basic properties to use to describe or talk about curriculum components. For this and other reasons, “honesty in packaging” is rare in the descriptive materials provided by publishers. This chapter supposes that in creating the curriculum equivalent of a brick structure, educators will have access to a large variety of accurate descriptions of bricks in the form of an easily accessible database. After defining what a curriculum block is, the chapter presents a template for describing blocks, some thoughts on how and by whom suitable blocks can be developed, and a brief list of some possible curriculum blocks.
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Rob Verdooren, L., i Dieter Rasch. "Useful Block Designs in Biostatistics". W Recent Advances in Biostatistics [Working Title]. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.1001858.
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Randomized Complete Block Designs(RCBD) , Balanced Incomplete Block Designs (BIBD) and the so called Generalized Lattice Designs Alpha Designs are useful designs in Biostatistics. A complete table of BIBDs with the smallest number b of blocks with at most v =25 treatments and block sizes k for 2<k≤v/2. is presented. Such a table did not exist until now. The analysis of the different block designs (Randomized Complete Block design, BIBDs and Alpha Design) is here not done with the commercial statistical packages SAS or SPSS. These packages can now only be hired for a year and are quite expensive. We used the package of R for the analysis, which is free of charge and it is now used in most Universities.
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Kabir, Raihan, Yutaka Watanobe, Keitaro Naruse i Rashedul Islam. "Effectiveness of Robot Motion Block on A-Star Algorithm for Robotic Path Planning". W Frontiers in Artificial Intelligence and Applications. IOS Press, 2022. http://dx.doi.org/10.3233/faia220241.
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Efficient path planning and minimization of path movement costs for collision-free faster robot movement are very important in the field of robot automation. Several path planning algorithms have been explored to fulfill these requirements. Among them, the A-star (A*) algorithm performs better than others because of its heuristic search guidance. However, the performance, effectiveness, and searching time complexity of this algorithm mostly depends on the robot motion block to search for the goal by avoiding obstacles. With this challenge kept in mind, this paper proposes an efficient robot motion block with different block sizes for the A* path planning algorithm. The proposed approach reduces robots’ path cost and time complexity to find the goal position as well as avoid obstacles. In this proposed approach, grid-based maps are used where the robot’s next move is decided by searching eight directions among the surrounding grid points. However, the proposed robot motion blocks size has a significant effect on path cost and time complexity of the A* path planning algorithm. For the experiment and to validate the efficiency of the proposed approach, an online benchmarked dataset is used. The proposed approach is applied on thousands of different grid maps with various obstacles, starting, and goal positions. The obtained results from the experiment show that the presented robot motion blocks reduce the robot’s pathfinding time complexity and number of search nodes by maintaining a minimum path cost towards the goal position.
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Yu, T. R. "Introduction". W Chemistry of Variable Charge Soils. Oxford University Press, 1997. http://dx.doi.org/10.1093/oso/9780195097450.003.0004.
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The constitution and properties of soils have their macroscopic and microscopic aspects. Macroscopically, the profile of a soil consists of several horizons, each containing numerous aggregates and blocks of soil particles of different sizes. These structures are visible to the naked eye. Microscopically, a soil is composed of many kinds of minerals and organic matter interlinked in a complex manner. In addition, a soil is always inhabited by numerous microorganisms which can be observed by modern scientific instruments. To study these various aspects, several branches of soil science, such as soil geography, soil mineralogy, and soil microbiology, have been developed. If examined on a more minute scale, it can be found that most of the chemical reactions in a soil occur at the interface between soil colloidal surface and solution or in the solution adjacent to this interface. This is because these colloidal surfaces carry negative as well as positive charges, thus reacting with ions, protons, and electrons of the solution. The presence of surface charge is the basic cause of the fertility of a soil and is also the principal criterion that distinguishes soil from pure sand. The chief objective of soil chemical research is to deal with the interactions among charged particles (colloids, ions, protons, electrons) and their chemical consequences in soils. As depicted in Fig. 1.1, these charged particles are closely interrelated. The surface charge of soil colloids is the basic reason that a soil possesses a series of chemical properties. At present, considerable knowledge has been accumulated about the permanent charge of soils. On the other hand, our understanding is still at an early stage about the mechanisms and the affecting factors of variable charge. The quantity of surface charge determines the amount of ions that a soil can adsorb, whereas the surface charge density is the determining factor of adsorbing strength for these ions. Because of the complexities in the composition of soils, the distribution of positive and negative charges is uneven on the surface of soil colloidal particles. Insight into the origin and the distribution of these charges should contribute to a sound foundation of the surface chemistry of soils.
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"Shimian Maifu Ambush on All Sides, a pipa piece shu calligraphy, one category of the literati’s self-cultivation and entertainment shu konghou angular harp Si silk, a category of ancient classification for musical instruments Sichuan Yangqin a local singing narrative genre in Sichuan Province sihu four-string bowed lute suona conical oboe tan plucking, a category of folk classification for musical instruments, meaning plucked instruments taoxun pottery ocarina taozhong pottery bell Tianjin Minjian Yinyue The great meeting of folk music in Tianjin City Shenghui tongbo brass cymbals Tu earth, a category of ancient classification for musical instruments Wenban Shi’er Qü Twelve civil short pieces, a collection of pipa pieces edited by Yang Yinliu and Cao Anhe in 1943 wenqü civil pieces wenzi pu character notation wo konghou half-tube plucked zither with frets on the soundboard wuqü martial pieces xiao vertical bamboo flute, similar to ancient chiba xianghege song, accompanied by instruments xiqin bowed lute xun egg or ball shaped wind instrument, comparable to ocarina yangqin dulcimer yanyue banquet music in the court Yayin Ji Collection of elegant music edited by Yang Yinliu in 1923–1929 yayue ceremonial court music yazheng zither yü a type of ancient sheng, mouth organ yü (different Chinese scraped wooden block character) yunluo small gong chime zheng bridged zither". W Tradition & Change Performance, 34. Routledge, 2012. http://dx.doi.org/10.4324/9780203985656-6.
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Iida, Tomohiro, Kazutomi Nakane i Naoki Aso. "Rebuilding of Tokyo’s SUITENGU shrine". W IABSE Conference, Kuala Lumpur 2018: Engineering the Developing World. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2018. http://dx.doi.org/10.2749/kualalumpur.2018.0443.
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<p>Tokyo’s Suitengu is a traditional Japanese shrine located in the urban area that is often visited by people praying for safe delivery in childbirth. There are two structural features which provide both quakeproof and high fire-resistance required in the urban area. Its main structural features are the integral base isolation system for several buildings of different sizes and the application of base isolation to the low-story section that extends throughout the entire shrine precincts. The second feature is main shrine buildings constructed with a traditional wooden visible interior and exterior and an inner structure of reinforced concrete that ensures both earthquake safety and fire- resistance. These features are useful to rebuilding the traditional buildings which is often seen in the developing world in rapid urbanization area which requires high safety of buildings.</p>
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Singh, Prashant, Seul-Yi Lee i Roop L. Mahajan. "An Experimental Investigation of the Contribution of Different Carbonaceous Nanomaterials to Thermal Conductance of Thermal Interface Materials". W ASME 2019 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/imece2019-11553.
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Abstract With the increasing demand for higher performance and progressive miniaturization of electronic packages, power densities and the attendant thermal dissipation requirements are expected to escalate. One of the important strategies to ensure reliable operation at the device and die (chip) levels is the use of Thermal Interface Materials (TIMs) to reduce the thermal resistance between the chip and the heat sink. In this study, we have carried out an experimental investigation to characterize thermal conductance of TIMs composed of commercially available graphene (c-rGO), graphene nanoplatlets (GNPs) of different lateral sizes (5, 15 and 25 μm), and our in-house produced thermally reduced graphene oxide at 600°C (T-rGO-600). These additives were loaded in a silicone rubber matrix where their loading fraction was fixed at 2% by weight. Thermal conductance of the resulting TIMs was determined by measuring heat flow, in steady state, through a TIM sandwiched between two metal blocks. The thermal conductance values representing the combined resistance of the composite material and the contact resistances between the TIM and the metal blocks were measured at different heat flux levels across the TIM. The results show that the thermal conductance values were independent of the heat load across the TIM as well as the TIM temperature. Further, a detailed investigation of the surface functionality and structural properties has revealed that the in-house produced T-rGO-600 has superior thermal conductance when compared to the above-mentioned carbonaceous nanomaterials, which are considered as potential candidates for enhancing thermal performance of TIMs. The data demonstrates that this result is attributable to the formation of the surface functional groups and the associated morphological changes during the reduction of graphene oxide to the T-rGO-600. Among the different GNPs tested, the GNP-15 exhibited superior thermal performance compared to the GNP-5 and GNP-25 samples.
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Sun, Jun, Yanhua Zheng i Fu Li. "Researches of Bypass Flows From Cold Plenum to Hot Plenum in HTR-PM by the Flow Network Method". W 2012 20th International Conference on Nuclear Engineering and the ASME 2012 Power Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/icone20-power2012-54045.
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Many graphite blocks in the core of the HTR-PM serve as the construction material, the neutron reflector and the flow paths of the helium. A small part of helium gas may flow in widely distributed gaps among graphite blocks and enter the hot plenum at low temperature. In our previous paper, a simple flow network combined with CFD simulations of complex flow paths was established to analyze the bypass flow in HTR-PM. In the present paper, the flow network was detailed by assigning more inner nodes and links in the pebble bed. In all kinds of bypass flow paths, only the bypass flow from cold plenum to hot plenum (P-P) was considered. Horizontal flow between the core and the P-P bypass flow path was also added into the flow network in various heights from the top to the bottom. The existence of the horizontal flow enhanced the helium exchange between the core and the bypass flow to different extent in different position, and finally changed the P-P bypass flow ratio. Moreover, gaps in larger sizes had more significant effects on the P-P bypass flows.
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Zagitov, R. A., A. N. Dushko i Yu N. Shmotin. "Automatic Three Dimensional Grid Generation in Turbo Machine Blade Passages". W ASME Turbo Expo 2014: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-27127.
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Generation of the grid for blade passages with packaging using universal grid generators usually takes much time. The paper is devoted to grid generation in turbo machine blade passages with packaging in automatic mode. The main requirement to the approach is to obtain the grid with minimum engineer participant. In the developed procedure engineer must specify only general input data: number of nodes, cell size near solid bodies and geometrical data. Multiblock structured grids are considered. All grid blocks have node-to-node attachment between each other; periodicity is also specified from node to node. The grid in blade passage consists of two blocks: “O” grid around blade and “H” grid in blade passage. Additional blocks are used to describe different ZR-effects such us tip clearances, leakage seals and bleed air systems. A variational method of constructing three dimensional grids composed of hexahedral cells is applied. The combination of the energy density functional and cell size functional is used. The first functional lets us control the shapes and the second functional lets us control the sizes of grid cells. Grid untangling procedure is also developed. Developed approach was tested using the blades of axial and centrifugal compressors and axial turbines. Results of grid generation are presented.
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Lazdins, Andis, Kristaps Makovskis, Agris Zimelis, Igors Gusarevs i Germans Gusarevs. "Productivity of new harvester prototype in willow plantations with different growing stock". W 22nd International Scientific Conference Engineering for Rural Development. Latvia University of Life Sciences and Technologies, Faculty of Engineering, 2023. http://dx.doi.org/10.22616/erdev.2023.22.tf002.
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A prototype of a mower-chipper typeharvester was developed for cutting small stems in cooperation between LSFRI Silava and SIA Laflora. The prototype produces chips and eco-pellets of various lengths in short rotation coppice, shelter belts and overgrown agricultural lands. The innovative element of the harvester is use of gravity force (bending of stems by a tractor own weight and formation of bunch of shoots with header and underframe) to feed in circular saws and chipper, thus significantly reducing energy demand for bending of shoots into the chipper, which is the most energy demanding operation in other commercial willow harvesters. Time studies were implemented in Skrīveri region in August 2022 in short rotation coppice fields established in 2011. Willows of tree different ages (1, 3 and 5 years) were harvested. The main factor influencing productivity in the study sites was growing stock of the coppice crops. The driving speed of the base machine cannot be significantly increased to avoid clogging of the chipper infeed and to retain good quality of chips; therefore, reduction of growing stock cannot be compensated with faster driving in the field. It was also noted that wood chip quality becomes significantly worse if the stump diameter of an average shoot is less than 1 cm and the saw blades are more often blocked by thin, flexible shoots. Similarly, clogging related issues were found in the 5 year old plantation. Optimal work conditions were in the 3 year old coppice crop; however, the driving speed of the base machine (MTZ82 tractor) was still too high. The recommended speed in such conditions is 0.8-1.2 km·h-1. The yield obtained in the tests under these conditions in the 3 year old coppice crop was 2.4 tons of dry matter per hour. The productivity could be raised by increasing the power of the base machine. There is still space for technical improvements to avoid clogging of material in the chipper and jamming of saw blades, as well as to improve the quality of chips.
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Sun, Y., C. Y. Kwok i K. Duan. "Size Effects on Crystalline Rocks Under Uniaxial Compression and Brazilian Tests". W 57th U.S. Rock Mechanics/Geomechanics Symposium. ARMA, 2023. http://dx.doi.org/10.56952/arma-2023-0440.
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ABSTRACT The tensile strength of crystalline rocks in Brazilian tests (BT) shows a more significant size dependency than the uniaxial compression strength in uniaxial compression tests (UCT), while the micro-mechanism is still unclear. This study seeks to elucidate the micro-mechanism by comparing different microcracking processes under UCT and BT. We adopt a grain-based model in the discrete element method (DEM) to reproduce the interlocked microstructure of crystalline rocks and perform UCT and BT with different sizes ranging from 0.5 to 3 times the standard sample size. It was found that peak stresses in UCT are nearly insensitive to sizes, which is consistent with experimental results measured at very low loading rates. Due to the homogenous stress distribution, no clear cracking paths are observed; instead, randomly distributed microcracks appear at failure. In contrast, numerical results indicate that the tensile strength measured in BT decreases as size increases and continuous cracking paths are observed at failure. Larger specimens have a higher possibility to include weaker cracking paths, hence tensile strength shows stronger size dependency. The findings of this work offer microscopic explanations for different size effects observed in UCT and BT, which can bridge the gap between laboratory-scale strength data and field-scale applications. INTRODUCTION Rock engineering applications often require assessing the strength and failure characteristics of rock masses. These rock masses are composed of intact blocks across various scales. However, the strength and cracking mechanism of these field-scale intact blocks are usually indirectly measured and studied through laboratory-scale tests on intact specimens (Duan et al., 2017; Duan and Kwok, 2015; Fei et al., 2021; Mahabadi et al., 2014; Martin and Chandler, 1994; Wong et al., 1996). Uniaxial compression test (UCT) and Brazilian tests (BT) are standard tests that measure the uniaxial compression strength (σf) and tensile strength (σt) of rocks (Eberhardt et al., 1999; Li and Wong, 2013; Martin, 1994). The sizes of UCT and BT specimens in the laboratory usually vary from 5-10 cm in diameter, much smaller than in fields. However, a dependence of strength on size is widely known in rocks (Bažant, 1984; Choo et al., 2023; Paterson & Wong, 2005). The strength determined by these laboratory-scale tests may overestimate the loading capacity in fields, and the cracking process observed in the laboratory-scale specimens may also not accurately manifest the failure mechanism in the field scale. Therefore, to apply laboratory-scale experimental data to practical applications, it is vital to investigate the influence of specimen size on strength and cracking patterns.
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Madenova, Y., F. T. Suorineni i Z. Mukhamedyarova. "Effects of Fractures on Seismic Wave Propagation Path: Laboratory Studies". W 57th U.S. Rock Mechanics/Geomechanics Symposium. ARMA, 2023. http://dx.doi.org/10.56952/arma-2023-0346.
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ABSTRACT In this study, discrete physical models using different blocks and hole sizes, and backfill characteristics are used to simulate changing underground mine conditions due to mining activities. In addition to voids and various backfills, this study includes fractures to investigate their effect on seismic wave propagation. The fracture systems in concrete blocks with sizes of 150 mm, 225 mm, 300 mm, 375 mm, and 450 mm were created by filling holes of various diameters in the concrete cubes with a static cracking agent (SCA). This process mimicked blast and stress-induced fracturing in the underground mine environment. AE measurements indicate that AE signal attenuation from fractures is more severe than due to backfill and in presence of fractures, backfill did not create a favorable environment for AE wave propagation toward receivers. AE signal arrival time to receivers mainly depends on the direction of AE wave propagation rather than the geometrical arrangement of the sensors in the presence of the voids, backfills, and fractures. AE signal arrivals to receivers are governed by the subsurface variability, Snell's law, and AE wave propagation direction. These factors should be considered to enhance the current source location approaches in microseismic monitoring systems. INTRODUCTION A major concern in deep underground mines is seismicity and rockburst of which frequency increases with mining depth. These phenomena significantly influence mine safety, productivity, and operating costs. Considering the undesirable impacts and consequences of seismic activities and rockbursts, their forecasting and control play a critical role in deep underground mines. Seismically active mines rely on microseismic monitoring systems to predict microseismic events and to minimize the exposure of personnel and equipment to seismic hazards. The microseismic monitoring system is able to identify, locate and quantify the mine seismicity enabling a better understanding of the rockburst mechanism.
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Hudyma, N., N. Walker i B. Chittoori. "Mapping and Characterization of Rockfall Runout Talus Deposits from Columnar Basalt Cliffs in Boise, ID". W 56th U.S. Rock Mechanics/Geomechanics Symposium. ARMA, 2022. http://dx.doi.org/10.56952/arma-2022-2071.
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ABSTRACT: The Boise Valley contains several columnar jointed basalt cliffs, which were deposited approximately 1.4 to 0.5 Ma on terraces formed by downcutting of the Boise River. Three runout talus deposits on Whitney Terrace were characterized using unmanned aerial vehicle visual imagery. Although the runout talus deposits were from different areas and were of varying size, they contained roughly the same dimensions and distributions of blocks. Images of the cliff face indicated that blocks were detached from the base of columns along horizontal discontinuities which lacked support (undercut columns) and by toppling of basalt columns. The mapped block sizes in the cliff face were larger than the blocks in the associated runout, indicating the cliff blocks were fragmented during impacts in the runout. 1. INTRODUCTION The movement of geologic materials downslope, commonly referred to as landslides, is one of the most well-known geologic hazards. Varnes (1978) developed the most widely used classification framework for landslides. Since the Varnes classification scheme was developed, various modifications have been proposed and adopted. Still, the goal is to be able to describe the movement(s) and the end result(s) of the landslide using well-known terminology which incorporates the focus of the investigators (Hungr et al., 2014). Our focus is to characterize the runout talus deposits formed from the dislodgement and subsequent downslope movement of rock blocks from columnar basalt cliffs. Columnar basalt, or specifically columnar jointing in basalt, is a type of rock mass that is divided into long prismatic blocks. The formation of the jointing is complex and thought to be a series of events rather than simple cooling of the lava. The vertical discontinuities are continuous and horizontal discontinuities are less prominent and generally end at the edges of the vertical discontinuities (Spry, 1962). Failures of rock masses with columnar jointing have been studied in several geographical locations, including Australia (Dahlhaus and Miner, 2000), Chile (Holm and Jakob, 2009), Spain (Abellán et al., 2011), and Washington State (Guzek, 2019). The failure mechanism most often reported in these studies has been the somewhat generic term "rockfall", even though the studies mentioned above have shown that two failure (detachment) modes occur, rockfalls and rock topples.
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Ingvarsdottir, Hildur, Carl Ollivier-Gooch i Sheldon I. Green. "Computational Study of the Flow Around a Ducted Tip Hydrofoil". W ASME 2002 Joint U.S.-European Fluids Engineering Division Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/fedsm2002-31198.
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Steady flow over rounded and ducted tip hydrofoils has been studied computationally using the CFDRC-ACE(U) flow solver and a k-ε turbulence model. The flow domains were gridded with a combination of C-H, H-H, tetrahedral and prism grid blocks and mesh sizes ranged from 350,000–550,000 cells. A good agreement in flow pattern was achieved between the numerical solutions and available experimental data. The computations show that the ducted tip hydrofoil sheds less bound circulation over the majority of the wing span than does a rounded tip hydrofoil with the same cross section and aspect ratio. Observation of the streamwise component of vorticity immediately downstream of the different hydrofoils shows that the vorticity from the ducted tip hydrofoil is shed in the shape of a duct instead of the concentrated circular vortex shed by the rounded tip hydrofoil.
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Yan, Qingdong, Yuanyuan An i Wei Wei. "Research on Fluid Flow Stability With Baffles of Different Size in a Hydrodynamic Coupling During Partially Liquid-Filled Operating Conditions". W ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/gt2017-65111.
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The hydrodynamic coupling is a power transmission device dependent on the liquid medium momentum change with the advantage of slow shock, isolation of torsional vibration, start light load and overload protection, which is applied in engineering, mining, construction, lifting the transport machinery, et al[1]. The hydrodynamic coupling without inner ring usually works in partially liquid-filled operating conditions, when the flow state changes suddenly with the rotating speed ratio changing. This may lead to unstable gas-liquid two-phase flow in a hydrodynamic coupling in a certain ratio range. To improve the stability of two-phase flow, a baffle is set inside the circulatory circle of a hydrodynamic coupling. The baffle blocks part of the flow area between two wheels in the hydrodynamic coupling. The size of baffle plays an important role on the effect for improving the flow stability. To investigate the influence of the baffle to the internal flow stability, the two-phase flow (liquid-filling rate is 80%) in hydrodynamic couplings with baffles in different sizes and without baffles were studied by Computational Fluid Dynamics (CFD) numerical simulation with the rotating speed of pump at constant 2200 r/min and rotating speed of turbine changing from 0 to 2200r/min. The corresponding distributions of streamlines and characteristics curves were obtained. Through the analysis of turbine torque and efficiency, it is verified that the baffle could improve the flow stability, and the different distributions of streamline could explain the reason. In addition, optimal range of baffle size c = 30% ∼ 40% is obtained by analyzing the simulation results. This will provide a basis for the improvement of design in the hydrodynamic coupling.
Raporty organizacyjne na temat "DIFFERENT SIZES OF WOODEN BLOCKS"
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Miles, Gaines E., Yael Edan, F. Tom Turpin, Avshalom Grinstein, Thomas N. Jordan, Amots Hetzroni, Stephen C. Weller, Marvin M. Schreiber i Okan K. Ersoy. Expert Sensor for Site Specification Application of Agricultural Chemicals. United States Department of Agriculture, sierpień 1995. http://dx.doi.org/10.32747/1995.7570567.bard.
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In this work multispectral reflectance images are used in conjunction with a neural network classifier for the purpose of detecting and classifying weeds under real field conditions. Multispectral reflectance images which contained different combinations of weeds and crops were taken under actual field conditions. This multispectral reflectance information was used to develop algorithms that could segment the plants from the background as well as classify them into weeds or crops. In order to segment the plants from the background the multispectrial reflectance of plants and background were studied and a relationship was derived. It was found that using a ratio of two wavelenght reflectance images (750nm and 670nm) it was possible to segment the plants from the background. Once ths was accomplished it was then possible to classify the segmented images into weed or crop by use of the neural network. The neural network developed for this work is a modification of the standard learning vector quantization algorithm. This neural network was modified by replacing the time-varying adaptation gain with a constant adaptation gain and a binary reinforcement function. This improved accuracy and training time as well as introducing several new properties such as hill climbing and momentum addition. The network was trained and tested with different wavelength combinations in order to find the best results. Finally, the results of the classifier were evaluated using a pixel based method and a block based method. In the pixel based method every single pixel is evaluated to test whether it was classified correctly or not and the best weed classification results were 81% and its associated crop classification accuracy is 57%. In the block based classification method, the image was divided into blocks and each block was evaluated to determine whether they contained weeds or not. Different block sizes and thesholds were tested. The best results for this method were 97% for a block size of 8 inches and a pixel threshold of 60. A simulation model was developed to 1) quantify the effectiveness of a site-specific sprayer, 2) evaluate influence of diffeent design parameters on efficiency of the site-specific sprayer. In each iteration of this model, infected areas (weed patches) in the field were randomly generated and the amount of required herbicides for spraying these areas were calculated. The effectiveness of the sprayer was estimated for different stain sizes, nozzle types (conic and flat), nozzle sizes and stain detection levels of the identification system. Simulation results indicated that the flat nozzle is much more effective as compared to the conic nozzle and its relative efficiency is greater for small nozzle sizes. By using a site-specific sprayer, the average ratio between the spraying areas and the stain areas is about 1.1 to 1.8 which can save up to 92% of herbicides, especially when the proportion of the stain areas is small.