Journal articles: 'Scraper'

1

Monnier, Gilliane F. "Middle Palaeolithic Scraper Morphology, Flaking Mechanics and Imposed Form: Revisitng Bisson's ‘Interview with a Neanderthal’." Cambridge Archaeological Journal 17, no. 3 (October 2007): 341–50. http://dx.doi.org/10.1017/s0959774307000406.

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Bisson (2001) proposes that imposition of form in Middle Palaeolithic scrapers can be recognized when the rules for scraper manufacture, which are based upon functional considerations, are known. He derives these ‘scraper production rules’ on the basis of experiments with novice flintknappers, and finds that they apply to Neanderthal-manufactured Mousterian scrapers. He interprets the violation of these rules in scrapers from Skhul Cave as evidence that anatomically modern humans imposed form on their stone tools, and therefore had mental templates. This study provides evidence that the ‘scraper production rules’ are not, in fact, the rules according to which Neanderthals made their tools. Instead, they reflect flaking mechanics and elements of Bisson's experimental design rather than any functional considerations taken into account during scraper manufacture. Furthermore, methodological flaws in Bisson's analysis of Middle Palaeolithic artefacts undermine his arguments that archaeological scrapers either follow or violate the rules. These problems render untenable his conclusion that Neanderthals did not have mental templates and that they lacked flexibility and innovation in stone-tool making.

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Haga, Toshio, Hiroshi Tsuge, Takuya Ishihara, Shinji Kumai, and Hisaki Watari. "A Vertical Type Tandem Twin Roll Caster for Clad Strip Equipped with a Scraper." Key Engineering Materials 611-612 (May 2014): 623–28. http://dx.doi.org/10.4028/www.scientific.net/kem.611-612.623.

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A vertical type tandem twin roll caster equipped with a scraper for the clad strip was invented. This roll caster could cast three layers clad strip which base strip had lower melting point than that of the overlay strips. The base strip was cast by an upper twin roll caster and the overlay strips were cast by a lower twin roll caster. The scrapers were attached to the lower twin roll caster, and were innovated to cast this type of three layers of clad strip. Solidification layers those became the overlay strips were pulled from between the scraper and the roll. The melt of the alloy which was as same as the base strip was poured between the scraper and the base strip. This melt connect the overlay strip and the base strip. The base strip was not re-melted. The scraper enabled that the solidification layer of the overlay strip contact to the melt of the base strip without mixing of the melt of the base and overlay strip. In this way, the sound three layers clad strip which base strip had lower melting point than that of the overlay strip could be cast by the vertical type tandem twin roll caster equipped with a scraper.

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Ebertz, Peter, Manuel Stephan Krommweh, and Wolfgang Büscher. "Feasibility Study: Improving Floor Cleanliness by Using a Robot Scraper in Group-Housed Pregnant Sows and Their Reactions on the New Device." Animals 9, no. 4 (April 22, 2019): 185. http://dx.doi.org/10.3390/ani9040185.

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Successful pig farming needs the best conditions of cleanliness in the housings. The present study examined for the first time whether a robot scraper usually applied in dairy farming is usable in sow housings for cleaning the slatted floors and improving hygiene and thus animal welfare. For evaluating the suitability of the robot scraper with regard to the cleaning performance (polluted surface area and occluded slots), the whole housing area was divided into score-squares, which were individually scored at defined intervals. Selected excrement quantities removed by the robot were weighed. In order to assess the animals’ interactions with the robot scraper, their behaviour towards the device was observed. Although the faeces of pigs had a firmer consistency than bovine excrement, excrement quantities of up to 1.4 kg m−2 were almost completely removed. Even 6 h after the cleaning its effect was still visible. Dry-cleaning led faster to nonslip surfaces for the sows than wet-cleaning. Within half an hour of observation, up to 8.2 of 120 sows were occupied with the robot scraper, but without harming it. The use of robot scrapers in pig housings is recommended, although slight technical modifications should be made to the robot scraper.

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Siegrist, H., P. Krebs, R. Bühler, I. Purtschert, C. Röck, and R. Rufer. "Denitrification in secondary clarifiers." Water Science and Technology 31, no. 2 (January 1, 1995): 205–14. http://dx.doi.org/10.2166/wst.1995.0103.

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Denitrification in secondary clarifiers is primarily due to hydrolysis of particulate degradable COD and decay of biomass. The reduction factor of these processes under anoxic as compared to aerobic conditions was investigated in the treatment plants of the City of Zurich. The Zürich-Glatt plant has circular clarifiers with central inlet. The treatment plant Zürich-Werdhölzli has rectangular clarifiers with cross flow and scrapers with vacuum removal of the sludge. At Zürich Glatt denitrification capacity in the clarifiers was 30% of total denitrification, whereas at Zürich-Werdhölzli only 15 % was observed. The sludge mass in the secondary clarifier depends on inlet flow, return sludge flow, activated sludge concentration, sedimentation properties of the sludge and scraper intervals. During dry weather and due to good sedimentation properties the activated sludge blanket in the thickening zone of the rectangular clarifiers at Zürich-Werdhölzli is almost completely removed after passage of the scraper. Denitrification volume in the secondary clarifier can therefore be modelled in relation to the ratio of inlet to return sludge flow and scraper interval. With the aid of control of return sludge flow and scraper intervals denitrification capacity in the secondary clarifiers may be improved. In order to control denitrification in the secondary clarifier the model must include a variable sludge volume in the clarifier related to scraper interval under the assumption of constant sludge mass in the entire system.

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Kravets, Sviatoslav, Oleksandr Lukyanchuk, Vladimir Suponyev, and Olexey Gaponov. "Method of calculating the parameters of the scraper working equipment of the trench excavator based on critical deep blocked soil cutting." Gіrnichі, budіvelnі, dorozhnі ta melіorativnі mashini, no. 96 (December 31, 2020): 5–12. http://dx.doi.org/10.32347/gbdmm2020.96.0101.

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The article presents a method of calculating the parameters of the scraper working equipment of a trench excavator that performs critical depth cutting: critical depth for its cutters, number of cutting lines, pitch of cutters, height of scrapers, cutting speed, working speed, length of plowshares of cutters, necessary effort of cutting of soil, power to drive the working equipment and movement, power selection of the base machine. Methodology/approach. To solve these problems, analytical methods were used to study the parameters of multi-scraper excavators that perform critical depth cutting of soils. Findings. The developed technique allows to create energy-efficient working equipment and to determine its critical-depth modes of operation, which make it possible to increase productivity and reduce the energy consumption of multi-scraper chain trench excavators that carry out blocked cutting of soils. Research limitations/implication. The initial data for the calculation are: the width of the cutters, their cutting angle, the maximum depth of the trench, the width of the trench, the physical and mechanical characteristics of the soil. Originality/value. Managed to achieve the prerequisites for reducing the energy intensity of soil development scraper chain excavators based on critical depth cutting of soils.

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Blades, Brooke S. "End Scraper Reduction and Hunter-Gatherer Mobility." American Antiquity 68, no. 1 (January 2003): 141–56. http://dx.doi.org/10.2307/3557037.

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Various lithic measures have been invoked to argue that human foragers moved over greater or lesser distances, or moved with greater or lesser frequency when compared with other foraging groups. This paper examines one of those measures—the reduction of blade end scrapers from early Upper Paleolithic Aurignacian and Perigordian occupations in southwestern France. Evidence of end scraper reduction is compared with faunal diversity and lithic material provenience, the former a potential catalyst of and the latter a potential reflection of mobility. A relationship between less-intense end scraper reduction, somewhat elevated percentages of distant raw materials, and reindeer-dominated fauna is noted during cold and apparently open environmental conditions. Less consistency in the extent of end scraper reduction is observed among assemblages associated with more diverse and at times less-mobile fauna. These observations argue for the importance of a fine-grained comparison of lithic and other data, the complexity of procurement strategies, and the recognition that greater or lesser reduction does not translate directly into greater or lesser mobility.

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Lee, Hyun-Kyung, Kwang-Hwan Choi, Jung-In Yoon, Choon-Geun Moon, Min-Ju Jeon, Joon-Hyuk Lee, Kwang-Seok Lee, and Chang-Hyo Son. "Performance Characteristics of a Seawater Ice-Making Device Using a Scraped Surface Double Tube Evaporator." Applied Sciences 8, no. 11 (October 25, 2018): 2063. http://dx.doi.org/10.3390/app8112063.

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In this study, to investigate the performance characteristics of a seawater ice-making device, using a scraped surface double tube evaporator, experiments were conducted under various operating conditions, including inlet temperature and flow rate of seawater, evaporating temperature, and scraper rotation speed. The main results are summarized as follows: (1) The section where stable ice making is possible, is determined by the inlet temperature and the flow rate range of seawater. By controlling the flow rate of seawater, the ice packing factor (IPF) of the device can be adjusted from 0.3 to 14.7%. (2) The IPF increases in cases where the evaporating temperature decreases linearly, until −13 °C. As the temperature of refrigerant that flows into the evaporator changes, the IPF is changed. Consideration is required for these connections. (3) The IPF increases when speeding up the scraper. The minimum rotating speed of the scraper was 350 rpm in these experiments. Optimum operating conditions for the seawater ice slurry maker are established through experiments. These results will be considered as important data for designing a slurry type seawater ice-making device.

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Cheban, Anton Yurievich, and Natalia Petrovna Khrunina. "Intensification of Open Mining Operations with a Small Distance of Transportation of Rock Mass." International Journal of Engineering Research in Africa 38 (September 2018): 100–114. http://dx.doi.org/10.4028/www.scientific.net/jera.38.100.

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Sometimes in open mining, it is economically expedient to extract and transport rock mass with the help of wheel tractors-scrapers. To improve the hopper filling with the rock mass operating with clay or loosened rocks, it is advisable to use scrapers equipped with loading intensifiers in the form of a raking wall located inside the hopper. The article presents the experimental filling study results of wheel tractor-scraper hopper models of different capacities with a standard and increased hopper length at the presence or absence of a raking wall. The investigations were carried out on an experimental rock removal bench equipped with a strain gauge measuring system to record forces that arise during the hopper model filling with rock mass. Data are given on the rock mass removal for various filling methods, as well as for the resistance values for the piling wall movement and the energy capacity of the hopper filling process for operating with sandy loam, loam, clay, and limestone crushed stone. There were realized the calculations of the operational productivity and the specific cost of works, depending on the rock mass transportation distance with elongated hopper scrapers equipped with a scraper wall, scrapers with standard hoppers and scrapers operating with a pusher bulldozer set. The rational application areas for each of the machines were revealed.

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9

Rogers, Richard A. "Spurred End Scrapers as Diagnostic Paleoindian Artifacts: A Distributional Analysis on Stream Terraces." American Antiquity 51, no. 2 (April 1986): 338–41. http://dx.doi.org/10.2307/279945.

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Analysis of archaeological sites on a stream terrace system in Kansas supports the idea that spurred end scrapers are valid diagnostic Paleoindian artifacts. No sites with spurred end scrapers were discovered on the Holocene terraces, while the Wisconsin terraces did yield such sites. The differential distribution of spurred end scraper sites on terraces appears to be statistically significant. The results are consistent with the hypothesis that spurred end scrapers were not found on the Holocene terraces because they were not being used when the Holocene terraces formed.

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10

Бурлака, О. А., and С. В. Яхін. "Підвищення ефективності роботи скребкових елеваторів з відцентровим типом розвантаження." Вісник Полтавської державної аграрної академії, no. 4 (December 28, 2018): 195–200. http://dx.doi.org/10.31210/visnyk2018.04.31.

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Підвищені енергетичні витрати на транспортування, висока ступінь подрібнення зерна пов’язані з наявними недоліками існуючих конструкцій скребкових елеваторів з відцентровим типом розвантаження, є зворотне осипання (колова циркуляція) зерна. Для усунення цього недоліку необхідно проаналізувати фактори, що впливають на напрямок потоку вантажу залежно від його швидкості та положення натяжного пристрою. За результатами експериментальних досліджень ефективності роботи скребкових елеваторів встановлено залежність зворотного сипу зерна в елеваторі (колової циркуляції) від швидкості транспортування та сектору розвантаження. Запропоновано враховувати особливості роботи натяжного механізму скребкового елеватору на зернозбиральних комбайнах та дообладнати верхню частину елеватора додатковим направляючим кожухом. When transporting grain, the return fall and, respectively, partial crushing of grain by scrapers, a chain and asterisks of an elevator are observed. It is because of detected imperfection of an elevator’s head design combined with a tension device The correction of a trajectory of a grain flow is carried out by a cover of an upper part of an elevator. If the time of the movement of grain on an elevator scraper surface is equal or smaller than the time of rotation of a scraper when passing a zone of unloading, then we have a high probability of hit of layers of a grain flow in necessary limits, at the same time centrifugal unloading is successfully. If the trajectory of grain layers gets to a lower zone, then there is a possibility of grain entering in a single part of a scraper elevator that is, the return rash, circular circulation of grain in an elevator casing, is formed. Such phenomenon is negative as it involves additional power costs of transportation; increases crushing and compression damage of grain weight, accelerates wear of operating parts of the grain transport system of the combine. The next part of the research, devoted to the ways of improvement of centrifugal unloading in a scraper elevator, is optimization of size of the sector of unloading. For the solution of such task we have conducted a number of researches by means of special experimental installation. It is possible to change the sector of a zone of unloading by means of change of height of unloading zone. Speed of transportation of grain was different with the change of turns of a power shaft with an asterisk to a chain occasion with scrapers. According to the result of the experiment measurement of power parameters of grain transportation by a scraper elevator is taken, at the same time it is found out that reduction of circular circulation in an elevator from 7-10% to 2-3% of the general supply of grain gives the chance to save 0,075-0,085 kW of power costs of transportation with a productivity of elevator of 5-5,5 kg/s. To eliminate this drawback, it is proposed to install an of the additional directing casing in the upper part of the scraper elevator of the additional directing casing . To eliminate this drawback, it is proposed to install an additional directing body in the upper part of the scraper elevator.

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Nakamura, Ryoji, Yusuke Shiotsu, Kosuke Komeda, Shinji Kumai, and Hisaki Warari. "Improvement of Porosity of Strip Using a Scraper on the Casting by a Vertical Type High Speed Roll Caster." Advanced Materials Research 146-147 (October 2010): 1108–13. http://dx.doi.org/10.4028/www.scientific.net/amr.146-147.1108.

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Porosity occurred in the 5182 aluminum alloy strip cast by a vertical type high speed twin roll caster. The porosity was caused by high-roll-speed and low-roll-load. Improvement of the porosity was tried by a scraper. The scraper was mounted on the roll, and the scraper was moveable depend on the thickness of the solidified layer on the roll. The scraper scribed the semisolid layer to improve the porosity. The scraper was useful to decrease the porosity of roll cast 5182 aluminum alloy strip.

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Burton, Adrian. "The snow scraper." Frontiers in Ecology and the Environment 10, no. 10 (December 2012): 584. http://dx.doi.org/10.1890/1540-9295-10.10.584.

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Yakhin, Sergey, Il'gam Masalimov, Marat Nafikov, and Ramis Mardanov. "OPTIONS FOR PLANE-PARALLEL MOVEMENT OF GRAINS IN A SCRAPER CONVEYOR." Vestnik of Kazan State Agrarian University 14, no. 4 (April 12, 2020): 96–99. http://dx.doi.org/10.12737/2073-0462-2020-96-99.

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The kinematics of plane-parallel motion of a wheat or rye grain when moving in an inclined position in a scraper conveyor is considered. A kinematic diagram of the plane-parallel motion of the grain in the scraper conveyor was compiled, the position of the instantaneous center of the flat figure was determined, and options for the movement of grain in an inclined position at various possible positions of instantaneous center were considered. The profile of the grains is outlined by an elliptical curve. The point of contact of the elliptical profile of the caryopsis with the scraper makes a complex motion, while the horizontal speed of the scraper is portable for it, the sliding speed on the surface of the scraper is relative. The speed of the touch point of the grain with the pan is horizontal. For six possible positions of the instantaneous center, the directions of the velocities of the points of contact of the grains and the friction forces acting in them are determined. Grains of wheat or rye, moved in a scraper conveyor, in some cases can make plane-parallel movement. The point of contact of the elliptical profile of the caryopsis with the scraper makes a complex motion, while the horizontal speed of the scraper is portable for it, the sliding speed on the surface of the scraper is relative. The speed of the touch point 2 of the grain with the pan is horizontal.

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Haga, Toshio, Kosuke Tsukuda, Keisuke Oida, Hisaki Watari, and Shinichi Nishida. "Casting of Al-Mg Strip Using Single Roll Caster Equipped with a Scraper." Key Engineering Materials 880 (March 2021): 49–56. http://dx.doi.org/10.4028/www.scientific.net/kem.880.49.

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A scraper was attached to an unequal-diameter twin-roll caster without requiring large modifications. This caster was used as a 1000 mm diameter single roll caster equipped with a scraper, and its strip casting ability was tested. The effects of the scraper angle and load, the roll speed, and the pouring temperature of the molten metal on the scribed surface, thickness distribution and average strip thickness were investigated. The scribed surface characteristics were sound and the thickness distribution was flat when the scraper angle was 60° and the scraper load was in the range of 1 to 4 kg. When the scraper load was more than 1 kg, the thickness distribution was uneven. The average strip thickness decreased as the roll speed increased. The pouring temperature of the molten metal influenced the evenness of the solidified layer thickness. The solidified layer became even as the molten metal temperature was decreased. A strip cast with the determined optimal conditions was then cold rolled down to 1 mm to improve its surface quality.

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Cao, Lian Min, Qing Liang Zeng, Jing Cui, and Hong Juan Yang. "Development of Hydraulic Security Shearing Machine for the Annulus Chain Used in Coal Mine." Advanced Materials Research 282-283 (July 2011): 371–74. http://dx.doi.org/10.4028/www.scientific.net/amr.282-283.371.

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In view of the situation of shearing the scraper chain frequently and adjusting the pitch chain of the scraper conveyer in the coal mine, the project design a kind of hydraulic security shearing machine for the annulus chain of scraper conveyer, to solve the problem for high strength and heavy gauge annulus underground coal mine to cut off.

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Xia, Rui, Xuewen Wang, Bo Li, Xing Wei, and Zhaojian Yang. "The prediction of wear on a scraper conveyor chute affected by different factors based on the discrete element method." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 17 (July 7, 2019): 6229–39. http://dx.doi.org/10.1177/0954406219861130.

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During long-term operation, the scraper conveyor chute is seriously attrited by the friction of coal, gangue, and scraper chain. In this study, the discrete element method was applied to establish the bulk coal–scraper conveyor interaction analysis model to predict the wear of a scraper conveyor chute during the transporting process. The wear of the chute was investigated under various working conditions and bulk coal characteristics. Results indicated that the chute wear has a negative correlation with the laying angle of the scraper conveyor and increased with the chain speed. The wear was more severe as the increasing of gangue content, hardness, and size of the coal particles. In addition, the wear degree in different sections on the chute was predicted. Results showed that the section near the coal falling point underwent more intense collisions and impact and, thus, the wear was more serious at this location. The wear loss decreased with the increasing distance away from this point. This research can be used for predicting the wear of a scraper conveyor working under different mines. What’s more, the wear-resistant treatment can be applied on the particular areas according to the mine conditions based on this study.

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Chivers, Benedict D., Thorin Jonsson, Carl D. Soulsbury, and Fernando Montealegre-Z. "Structural biomechanics determine spectral purity of bush-cricket calls." Biology Letters 13, no. 11 (November 2017): 20170573. http://dx.doi.org/10.1098/rsbl.2017.0573.

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Bush-crickets (Orthoptera: Tettigoniidae) generate sound using tegminal stridulation. Signalling effectiveness is affected by the widely varying acoustic parameters of temporal pattern, frequency and spectral purity (tonality). During stridulation, frequency multiplication occurs as a scraper on one wing scrapes across a file of sclerotized teeth on the other. The frequency with which these tooth–scraper interactions occur, along with radiating wing cell resonant properties, dictates both frequency and tonality in the call. Bush-cricket species produce calls ranging from resonant, tonal calls through to non-resonant, broadband signals. The differences are believed to result from differences in file tooth arrangement and wing radiators, but a systematic test of the structural causes of broadband or tonal calls is lacking. Using phylogenetically controlled structural equation models, we show that parameters of file tooth density and file length are the best-fitting predictors of tonality across 40 bush-cricket species. Features of file morphology constrain the production of spectrally pure signals, but systematic distribution of teeth alone does not explain pure-tone sound production in this family.

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Wang, Can, Yuanbin Fang, Song Huang, Guizhi Zhang, Qingyu Meng, and Xi Liu. "Optimization design of scraper angle based on orthogonal test." MATEC Web of Conferences 175 (2018): 02005. http://dx.doi.org/10.1051/matecconf/201817502005.

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The scraper angle of milling machine has a direct effect on the milling efficiency. This research establishes the finite element model of scraper, and designs the cutting front angle and the cutting back angle as factor, impact force and the average force for orthogonal test of evaluation indexes. Through simulation analysis, the force is obtained at the different level. At the same time, the simulation results are verified by experiments. The results show that the simulation results of contact force in the X direction are close to the measured results, and prove the accuracy of the simulation results. The optimized scraper is that the cutting angle is 5.5°, and the cutting back angle is 9°. The impact force is minimum, and the resultant of average force and impact force is minimum. The optimization of scraper angle can effectively reduce the impact force and the average force, which provides guidance for the improvement of scraper.

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Weedman, Kathryn J. "On the Spur of the Moment: Effects of Age and Experience on Hafted Stone Scraper Morphology." American Antiquity 67, no. 4 (October 2002): 731–44. http://dx.doi.org/10.2307/1593801.

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North American archaeologists often designate spurs on scrapers as gravers or use them as temporal markers for the Paleoindian Period. The functional and stylistic aspects of spurred scrapers are explored here through an ethnoarchaeological study of stone scraper procurement, production, use, and discard among the Gamo of southern Ethiopia. This research demonstrates that the presence of so-called “graver” spurs does not have a functional significance, but is the result of inexperience and/or the waning strength of the hideworker. Furthermore, spurred scrapers occur in abundance at villages where breakage rates also are high, reflecting the presence of a number of inexperienced hideworkers. Lastly, this paper explores the relationship between the experience of the knapper and tool standardization. The analysis suggests that in lineage-based learning systems more-experienced hideworkers assist less-experienced hideworkers, and thus blur any relationship between experience and standardization.

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Nilov, V. A., and E. V. Fedorov. "Increasing productivity trailed scraper." Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta 2, no. 4 (December 25, 2016): 64–70. http://dx.doi.org/10.22281/2413-9920-2016-02-04-64-70.

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Davydov, S. Ya, I. D. Kashcheev, and S. N. Sychev. "Vertical tubular scraper conveyers." Refractories and Industrial Ceramics 51, no. 6 (March 2011): 416–18. http://dx.doi.org/10.1007/s11148-011-9340-y.

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Zhuang, Min, Ge Li, Kexin Ding, and Guansheng Xu. "Optimized Design of Mechanical Chain Drive Based on a Wireless Sensor Network Data Algorithm." Journal of Sensors 2021 (September 13, 2021): 1–13. http://dx.doi.org/10.1155/2021/2901624.

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In this paper, we use a wireless sensor network data algorithm to optimize the design of mechanical chain drive by conducting an in-depth study of the mechanical chain drive optimization. We utilize the crowdsourcing feature of the swarm-wise sensing network for assisted wireless sensor networking to achieve crowdsourcing-assisted localization. We consider a framework for crowdsourcing-assisted GPS localization of wireless sensor networks and propose two recruitment participant optimization objectives, namely, minimum participants and time efficiency, respectively. A model and theoretical basis are provided for the subsequent trusted data-driven participant selection problem in swarm-wise sensing networks. The sprocket-chain engagement frequency has the greatest influence on the horizontal bending-vertical bending composite in different terrain conditions. The dynamic characteristics under working conditions are most influenced, while the scraping of the scraper and the central groove significantly influenced horizontal bending and vertical bending. Under load conditions, the amplitude of the scraper and central groove scraping increases significantly, which harm the dynamics of the scraper conveyor. By monitoring the speed difference between the head and tail sprockets and the overhang of the scraper, the tensioning status of the scraper conveyor chain can be effectively monitored to avoid chain jamming and chain breakage caused by the loose chain, thus improving the reliability and stability of the scraper conveyor.

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Kuhn, Steven L. "Blank Form and Reduction as Determinants of Mousterian Scraper Morphology." American Antiquity 57, no. 1 (January 1992): 115–28. http://dx.doi.org/10.2307/2694838.

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Variation in the forms of Mousterian tools has been attributed to a number of factors, including style, function, and more recently, differential reduction. This study compares the influences of two factors, reduction and the shapes of tool blanks, on the forms of scrapers from a Mousterian site in Italy. In the subject assemblages, the shapes of the tool blanks had a much stronger influence on scraper forms than had reduction. To the extent that blank form affects typology in other cases, explanations of contrasts among Mousterian assemblages would need to account for the use of alternative techniques of flake production. Since typological variation is multicausal, it would also appear more profitable to focus directly on variables pertinent to current research issues, rather than on reinterpreting the typology.

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Zhao, Bin, Yuanbin Fang, and Linjie Zhang. "Application of brazing process design in optimization structure design of scraper." MATEC Web of Conferences 175 (2018): 03017. http://dx.doi.org/10.1051/matecconf/201817503017.

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To effectively enhance the service life, the research of milling machine scraper structure design and welding process are optimized. Through the structural optimization analysis, the improved structure is obtained, and the working resistance force is reduced. The full factor test is used to optimize the brazing process, and the best parameters are obtained, which improves the shear strength. The accuracy of the model is verified by experiments. The results show that compared with the working resistance force, the improved scraper tends to be slow and the peak value is smaller. The cutting rake and relief angle of the scraper are optimized. When the cutting rake angle is 6° and the cutting relief angle is 9°, both working resistance force and impact force are minimum. It proves the accuracy of the simulation results. Using CT861 solder, brazing temperature is 75°C, and the brazing time is 10s. While the cooling method uses furnace cold, the minimum value of shear strength is 200MPa. The average working life of the scraper is raised from 800 hours to 1600 hours after the optimization design. Research results have guiding significance for the structure design and the welding process optimization of the scraper.

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Widyastuti, Ratih. "PERBEDAAN ANTARA MENYIKAT GIGI DENGAN MENYIKAT GIGI DISERTAI PENGGUNAAN TONGUE SCRAPER PADA PASIEN HALITOSIS." Jurnal Ilmiah dan Teknologi Kedokteran Gigi 17, no. 1 (July 23, 2021): 35–42. http://dx.doi.org/10.32509/jitekgi.v17i1.1310.

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Latar belakang: Halitosis atau bau mulut adalah bau yang tidak enak yang berasal dari rongga mulut. Halitosis menjadi permasalahan kesehatan mulut yang mempengaruhi psikologi dan kehidupan sosial. Halitosis berasal dari gas Volatile Sulfur Compounds (VSCs) yang terdiri atas hydrogen sulfida, metil merkaptan, dan dimetil sulfida. Cara mekanis menghilangkan halitosis dengan menyikat gigi dan penggunaan tongue scraper. Tujuan penelitian ini adalah membandingkan menyikat gigi dengan menyikat gigi disertai penggunaan tongue scraper pada pasien halitosis. Metode: Pasien dewasa dengan halitosis secara acak diminta untuk menyikat gigi atau menyikat gigi disertai penggunaan tongue scraper. Metode organoleptik digunakan untuk mengukur halitosis sebelum dan sesudah perlakuan. Hasil penelitian: Sampel sejumlah 45 orang dibagi secara acak menjadi 2 kelompok perlakuan. Sebelum perlakuan, skor halitosis secara statistik tidak terdapat perbedaan yang bermakna antar ke dua kelompok. Antara sebelum dan sesudah perlakuan, secara statistik terlihat reduksi halitosis pada ke dua kelompok. Sesudah perlakuan secara statistik terdapat perbedaan skor halitosis yang signifikan antar ke dua kelompok. Kesimpulan: Terjadi reduksi halitosis baik pada menyikat gigi ataupun pada menyikat gigi disertai penggunaan tongue scraper. Reduksi halitosis pada menyikat gigi disertai penggunaan tongue scraper lebih besar dibandingkan hanya dengan menyikat gigi saja. Hasil penelitian ini diharapkan bermanfaat bagi perawatan pasien halitosis.

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Asmawati, Asmawati. "Department of Oral Biology Faculty of Dentistry Hasanuddin University Makassar, Indonesia." Journal of Dentomaxillofacial Science 10, no. 3 (October 30, 2011): 156. http://dx.doi.org/10.15562/jdmfs.v10i3.275.

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Oral infections can be caused by the many microorganisms that occupy the oral cavity. Tongue is one of thevulnerable areas of the oral cavity occupied by microorganisms, in which colonized bacteria may cause disease.Mechanical tongue cleansing using tongue scraper can reduce anaerobic bacteria on dorsal of the tongue. Theobjective of this study was to observe the difference of anaerobic bacteria amount on dorsal of the tongue before andafter mechanical tongue cleansing using tongue scraper. This was laboratory experimental study with sampleconsists of 25 students selected by random sampling method. The results showed that the amount of bacteria isdecreased approximately 28% after tongue cleansing using tongue scraper. Based on the statistical analysis with tteston α=0.05, there is a difference on the amount of anaerobic bacteria on dorsal of the tongue before and aftermechanical tongue cleansing using tongue scraper.

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Siregar, Rolan. "Perkiraan Kekuatan Struktur Mekanik Side Scraper dengan Metode Elemen Hingga Beserta Rekomendasi Material Pengganti Elemen Kritis." ROTASI 21, no. 4 (October 23, 2019): 251. http://dx.doi.org/10.14710/rotasi.21.4.251-257.

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Salah satu jenis alat pengeruk tumpukan material ke belt conveyor dalam suatu industri pertambangan adalah side scraper. Beberapa elemen penyusun alat berat tersebut memiliki life time yang relatif singkat (elemen kritis) karena keterbatasan kekuatan struktur pendukung dalam menahan beban statis maupun kinetis. Adapun elemen yang mengalami kegagalan material adalah lengan brace, pylon, dan lengan scraper. Oleh karena itu dalam penelitian ini dilakukan perhitungan kekuatan struktur mekanik side scraper dan rekomendasi material pengganti elemen yang retak. Adapun metode penelitian ini dilakukan dengan simulasi tegangan berbasis metode elemen hingga. Dalam analisis statik diperoleh rekomendasi material berdasarkan perhitungan tegangan pada struktur mekanik tersebut. Adapun material yang digunakan terdiri dari dua jenis yaitu AISI Steel 1040, AISI Steel 1340. Penggunaan jenis material yang tidak seragam dimaksudkan untuk mengoptimalkan harga ekonomis material penyusun struktur mekanik tersebut. Akhir dalam penelitian ini diharapkan dapat berguna untuk maintenance peralatan side scraper.

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Nakamura, Ryoji, Kazuya Akitsu, Takanori Yamabayashi, Shinji Kumai, and Hisaki Watari. "Strip Casting by a Single Roll Caster Equipped with a Scraper." Key Engineering Materials 443 (June 2010): 122–27. http://dx.doi.org/10.4028/www.scientific.net/kem.443.122.

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A scraper was equipped to a single roll caster to improve the free solidified surface. The scraper contacted to the free solidified surface at the constant force. The some mount of semisolid layer at the surface was removed and the surface became flat. The scraper was made from the mild steel plate. The mild steel plate was covered by the insulator paper to prevent the cooling of the melt by the plate. The melt pool was made on the roll by the side dam plates, back dam plate and the scraper. Therefore, a tip or a nozzle was not needed. The AA5182 and AA6022 aluminum alloy were cast. The as-cast strips could be cold rolled. The microstructure of as-cast strip was not uniform at thickness direction. However, the microstructure became uniform after the cold rolling and the annealing.

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Mao, Ping Huai, Li Ding, and Jing Xi Li. "The Green Design of Bracket of Scraper Part of Coal Mine Underground Horizontal Extension Transfer Machine." Advanced Materials Research 591-593 (November 2012): 44–47. http://dx.doi.org/10.4028/www.scientific.net/amr.591-593.44.

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Recently, transporting coal in the coal mine is poor efficiency and too costly. Coal mine underground horizontal extension transfer machine is used to transport coal faster and better. To resolve the problem how to connect the scraper conveyer with tramcar in this system, the design of the bracket has been brought up. The bracket of scraper part is the main bearing of coal mine underground horizontal extension transfer machine, and all the scraper conveyer must be fixed in the bracket. In addition, the design of the bracket of scraper part not only considers the rationality in the structure, but also considers the effect of the environment. The system works in extreme circumstances, but the green design can resolve it. It can effectively combine the choice of material, the structure of the bracket, the methods of technology with exterior styling, reflecting the human, machine of harmony with the working environment.

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Góes, Joelmir Da Silva, Andrea Gomes Dellovo, Carla Rocha Sao Mateus, and Guilherme De Oliveira Macedo. "Effect of Polyethylene Terephthalate Tongue Scraper on Oral Levels of Volatile Sulfur Compounds: a randomized clinical trial." Brazilian Dental Science 22, no. 1 (January 31, 2019): Process. http://dx.doi.org/10.14295/bds.2019.v22i1.1671.

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Objective: To evaluate the effect of Polyethylene Terephthalate (PET) tongue scraper on the volatile sulfur compound (VSC) levels. Material and Methods: A randomized, controlled, parallel design was used in this study. Out of the 48 volunteers from Dentistry Department of the Federal University of Sergipe, 40 subjects who met the inclusion criteria were randomly divided into 4 groups (n=10): G1 (control), rinsing of distilled water solution (WS); G2, WS and tongue coating removal (TCR) with toothbrush; G3, WS and TCR with a commercial tongue scraper; and G4, WS and TCR with PET tongue scraper. PET bottles were cut with a rectangular shape (1.0 cm wide x 20 cm long) to obtain PET tongue scraper. The VSC measurements were performed before (T0) and immediately after (T1) each therapy by portable sulfide monitor. Data (ppb) were submitted to Wilcoxon test (α=0.05). The differences between T0 and T1 were calculated and percentage values were assigned. Data (percentage) were submitted to ANOVA and Tukey test (α=0.05). Results: All 40 selected subjects completed the study. All groups reduced significantly the VSC levels after therapy (P<0.01). ANOVA indicated a significant difference among groups (P<0.001). The Tukey test showed that G1 (reduction of 21%) was similar to G2 (31%); G2 was similar to G3 (42%) and different from G4 (52%); G3 and G4 were similar. Conclusion: PET tongue scraper was similar to commercial tongue scraper and provided higher reductions of VSC levels than the toothbrush. KeywordsHalitosis; Polyethylene terephthalates; Sulfur compounds; Tongue.

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Mathew, Sony J., and Sushama G. Deo. "Some Observations on the Middle Palaeolithic Culture in North-Western Karnataka with Special Reference to the Site of Kovalli." Artha - Journal of Social Sciences 11, no. 3 (July 18, 2012): 119. http://dx.doi.org/10.12724/ajss.22.6.

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The Middle Palaeolithic culture has been widely distributed in the Ghataprabha basin, obtained from 113 sites. The majority of the sites are concentrated in the middle and lower reaches of the river Ghataprabha and the assemblage is comprised of scrapers of various types, points, borers and scraper cum borer and borer cum points. The studies conducted at the site Kovalli which lies in the lower reaches of Ghataprabha suggest that the Kovalli assemblage can be categorized as mixture of Middle Palaeolithic and late Middle Palaeolithic. It can be categorized as “advanced” Middle Palaeolithic.Keywords: Assemblage; Middle palaeolithic, Naturally backed knife; Palaeolithic

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Phillips, Cassie, Jeremy Stovall, Hans Williams, and Kenneth Farrish. "Using the Forestry Reclamation Approach for Reclaimed Surface Mineland in the Western Gulf: Effects on Pinus taeda Seedling Growth and Survival." Forests 12, no. 7 (June 26, 2021): 845. http://dx.doi.org/10.3390/f12070845.

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While land reclamation efforts of surface mines have considerably increased soil stability since the implementation of SMCRA (Surface Mining Control and Reclamation Act), research suggests that resulting soil compaction hinders the productivity of forests post-mining. The Forestry Reclamation Approach (FRA) was developed to improve forest health in the Appalachian region through a five-step process that minimizes soil compaction and establishes a productive forest. The FRA has not yet been tested in the western Gulf Coastal Plain (GCP). The higher clay content of some GCP soils and the dearth of coarse fragments (e.g., cobbles, stones and boulders) may affect reclamation practices and the ability of these methods to create productive forests. Compaction caused by conventional reclamation methods in the GCP has not been studied in great detail. Thus, this study attempts to provide a comparison of two reclamation methods, FRA low-compaction method used in the Appalachian region with that of conventional scraper-pan (scraper) methods in the GCP. This study used the FRA with common silvicultural practices of the western Gulf. The two hectare study site was installed with a randomized complete block design with three replicates comparing conventional scraper reclamation used in the region with that of an unmined control and the FRA-style low compaction treatment. Following soil reclamation, containerized loblolly pine (Pinus taeda L.) seedlings of a western Gulf provenance were hand-planted. Soil chemical and physical parameters were assessed on each treatment to determine the effect the FRA and scraper method had on resulting tree seedling growth and survival. After three growing seasons, seedlings in the FRA plots had significantly greater tree volumes than both the scraper (p = 0.0139) and the control (p = 0.0247) treatments. The FRA plots also had a 97% survival rate, while scraper plots had a survival of 86%. The FRA plots had significantly lower soil bulk densities than scraper (p = 0.0353) and control (p < 0.0001) plots which likely influenced growth and survival trends. Soil nutrients were increasingly available on the FRA and scraper plots, likely due to mixing of the soil profile when compared to the unmined control. Leaf-level water potential and gas exchange were not correlated to growth and survival and did not differ among treatments. These results suggest reclamation practices modeled after FRA methods may benefit tree growth and survival in the Western Gulf.

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Ramadan, Sigit Rizqi, and Bana Handaga. "Forlap Scraper menggunakan Aplikasi Android." Emitor: Jurnal Teknik Elektro 20, no. 1 (October 18, 2019): 21–28. http://dx.doi.org/10.23917/emitor.v20i1.8434.

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Hlushkova, D., E. Voronova, and S. Demchenko. "INCREASING RESOURCE OF SCRAPER CONVEYORS." Bulletin of Kharkov National Automobile and Highway University 1, no. 88 (October 9, 2020): 67. http://dx.doi.org/10.30977/bul.2219-5548.2020.88.1.67.

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Mischuk, Dmitry, Volodymer Voliyanuk, and Eugeniy Gorbatiuk. "IMPROVEMENT OF THE EQUIPMENT Scraper." Gіrnichі, budіvelnі, dorozhnі ta melіorativnі mashini, no. 88 (December 30, 2016): 78–83. http://dx.doi.org/10.26884/damu.a168811.

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Eikhout, Sandra M., Robin E. Bronkhorst, and Maarten P. van der Grinten. "Evaluation of a New Scraper." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 45, no. 7 (October 2001): 722–26. http://dx.doi.org/10.1177/154193120104500710.

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CARMICHAEL, DAVID G. "OPTIMAL PUSHER-SCRAPER LOADING POLICIES." Engineering Optimization 12, no. 4 (October 1987): 255–67. http://dx.doi.org/10.1080/03052158708941101.

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Sel'skii, B. E. "Hydraulic calculation of scraper crystallizers." Chemical and Petroleum Engineering 32, no. 5 (September 1996): 407–9. http://dx.doi.org/10.1007/bf02416569.

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Eyzenakh, Denis, Anton Rameykov, and Igor Nikiforov. "High Performance Distributed Web-Scraper." Proceedings of the Institute for System Programming of the RAS 33, no. 3 (2021): 87–100. http://dx.doi.org/10.15514/ispras-2021-33(3)-7.

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Over the past decade, the Internet has become the gigantic and richest source of data. The data is used for the extraction of knowledge by performing machine leaning analysis. In order to perform data mining of the web-information, the data should be extracted from the source and placed on analytical storage. This is the ETL-process. Different web-sources have different ways to access their data: either API over HTTP protocol or HTML source code parsing. The article is devoted to the approach of high-performance data extraction from sources that do not provide an API to access the data. Distinctive features of the proposed approach are: load balancing, two levels of data storage, and separating the process of downloading files from the process of scraping. The approach is implemented in the solution with the following technologies: Docker, Kubernetes, Scrapy, Python, MongoDB, Redis Cluster, and СephFS. The results of solution testing are described in this article as well.

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Haga, Toshio. "Strip casting using a roll caster equipped with a scraper." MATEC Web of Conferences 326 (2020): 06003. http://dx.doi.org/10.1051/matecconf/202032606003.

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An Al-Mg strip without center segregation could be cast using a single-roll caster equipped with a scraper at speed of 40 m/min. The scraper was useful for flattening a free solidified surface and for cooling the solidification layer by pushing the solidification layer to the roll. Clad strips consisting of 1) an Al-Mn base strip and an Al-Mg overlay strip and 2) an Al base strip and an Al-Sn-Cu overlay strip could be cast using an unequal-diameter twin-roll caster equipped with a scraper at speeds of 30 m/min and 15 m/min, respectively. The base strip and overlay strip were strongly bonded at the interface between the base strip and the overlay strip. The elements of the overlay strip did not diffuse into the base strip. The scraper played two roles in the casting of the clad strip: prevention of the mixture of two kinds of molten metal and making the surface of the base strip a semisolid of high solid fraction.

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Haga, Toshio. "600 mm-Wide Strip Casting Using Single Roll Caster Equipped with Scraper." Key Engineering Materials 805 (June 2019): 43–49. http://dx.doi.org/10.4028/www.scientific.net/kem.805.43.

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The casting of a 600 mm-wide 5182 aluminum alloy strip was attempted using a single-roll caster equipped with a scraper. This caster could cast a strip at speeds ranging from 10 to 40 m/min. These casting speeds are much higher than that of a conventional twin-roll caster. The scraper load suitable for scribing the wide strip was investigated. The strip could be scribed at full width by the scraper. The mechanical properties of the strip were investigated using a tension test and a cup test. The tensile stress was 320 MPa and the elongation was 30%. When deep drawing was conducted, no striped pattern, which occurs via segregation, appeared when both surfaces were facing outside.

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Haga, Toshio, and Kazuya Akitsu. "Improvement of Free Solidified Surface of Strip Cast Using a Single Roll Caster by Scribing Semisolid Layer." Solid State Phenomena 192-193 (October 2012): 488–93. http://dx.doi.org/10.4028/www.scientific.net/ssp.192-193.488.

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AA5182 alloy was cast using the single roll caster equipped with the scraper. Improvement of flatness of the free solidified surface of the strip cast by a single roll caster was tried by scribing of semisolid layer using a scraper. The semisolid layer could be scribed and be made flat by the scraper. The scribing force was controlled by a dead weight. Defects which occurred on the scribed surface were investigated. The property of the free solidified surface (scribed surface) was compared with roll contact surface by the deep drawing test. The property of the scribed surface was almost as same as that of the roll contact surface. Mechanical property was investigated by the tension test.

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Liu, Na, Dian Long Zou, Tian Jiao Zhou, and Jian Wei Zhao. "Modal Analysis of Scraper Chain Industrial Robot System." Applied Mechanics and Materials 490-491 (January 2014): 1190–93. http://dx.doi.org/10.4028/www.scientific.net/amm.490-491.1190.

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This paper researched dynamic characteristics of 5-DOF scraper chain handling robot by finite element modal analysis. Firstly established the whole three-dimensional model with Solidworks, secondly, transferred it into the ANSYS finite element analysis software to analyze dynamic characteristics in two fixed work positions when it was grasping a scraper chain and carrying a scraper chain on a rail line. It was found the weak component which vibrated heavily was the big arm from the analysis of the top 5 order vibration mode. Then studied modal analysis of the big arm to obtain the its inherent frequency and vibration mode. Finally put forward some suggestions about the design of the handling robot and improved its dynamic characteristics which is meaningful to increase its stability and reliability.

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Xia, Rui, Xuewen Wang, Bo Li, Xing Wei, and Zhaojian Yang. "Discrete Element Method- (DEM-) Based Study on the Wear Mechanism and Wear Regularity in Scraper Conveyor Chutes." Mathematical Problems in Engineering 2019 (January 3, 2019): 1–12. http://dx.doi.org/10.1155/2019/4191570.

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The scraper conveyor is the key conveying equipment for fully mechanized coal mining. Wear failure of the chute is the main form of failure of the scraper conveyor. In this study, the discrete element method (DEM) was combined with the wear model. The wear mechanism and wear regularity of the chute were explored by tracking the changes in the position of coal particles during the wear process. After the validation of wear simulation, a wear test of coal for different intrinsic parameters was designed. In one wear cycle, the three-body wear was about 32.84 times that of the two-body wear. In the research range, the wear of the scraper conveyor chute increased with the increase of Poisson’s ratio, shear modulus, and density of the coal. The shear modulus showed remarkable effect on the wear of the chute, followed by Poisson’s ratio and density. There existed a linear relationship between the shear modulus and wear (R2 = 0.8232). This study is expected to be used to predict the wear of the scraper conveyor chute and provide a theoretical basis for the applicability of the chute in different mines.

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Hidayat, Erwin Yudi, Fahri Firdausillah, Khafiizh Hastuti, Ika Novita Dewi, and Azhari Azhari. "Automatic Text Summarization Using Latent Drichlet Allocation (LDA) for Document Clustering." International Journal of Advances in Intelligent Informatics 1, no. 3 (December 1, 2015): 132. http://dx.doi.org/10.26555/ijain.v1i3.43.

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In this paper, we present Latent Drichlet Allocation in automatic text summarization to improve accuracy in document clustering. The experiments involving 398 data set from public blog article obtained by using python scrapy crawler and scraper. Several steps of clustering in this research are preprocessing, automatic document compression using feature method, automatic document compression using LDA, word weighting and clustering algorithm The results show that automatic document summarization with LDA reaches 72% in LDA 40%, compared to traditional k-means method which only reaches 66%.

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Haga, Toshio, Kazuya Akitsu, Shinji Kumai, and Hisaki Watari. "Roll Casting of Aluminum Alloy Strip by a Single Roll Caster Equipped with a Scraper." Advanced Materials Research 445 (January 2012): 307–12. http://dx.doi.org/10.4028/www.scientific.net/amr.445.307.

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A single roll caster equipped with a scraper was devised to cast the strip with sound free solidified surface. A property of this single caster is equipment of the scraper. Semisolid metal on the free solidified surface was scribed by a scraper and the surface became flat. Center line segregation did not occur as the strip was solidified from single side. The AA5182 aluminum alloy could be cast at speeds up to 40m/min. Thickness was about 3mm. Pressure of the unit width from the scraper was ranging from 0.1N/mm to 1.0N/mm, and these pressure was enough to make the free solidified surface flat. Roll cast strip could be cold rolled down to 1mm. There was not difference between roll contact surface and the free solidified surface after cold rolling by a visual examination. Result of tension test of the roll cast strip was as same as that of D.C. cast and rolled strip. Deep drawing test was operated at the conditions both of the roll contact surface and the free solidified surface was outside. LDR (limited drawing ratio) was same at both conditions and they were 1.8. Thickness of the strip was controlled by the roll speed, solidification length (length of the melt pool) and pressure of the scraper. The single roll caster is simpler than a twin roll caster. Rigidity for rolling was not needed for the single roll caster. Cost of the roll is half comparing a twin roll caster. The equipment cost of the single roll caster is more economy than that of the twin roll caster.

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Siddiqui, A. M., A. Imran, M. Zeb, and M. A. Rana. "Magnetohydrodynamic flow of Newtonian fluid in a scraped surface heat exchanger." Canadian Journal of Physics 93, no. 10 (October 2015): 1088–99. http://dx.doi.org/10.1139/cjp-2014-0195.

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This paper aims to study a mathematical model of electrically conducting incompressible Newtonian fluid flow in a scraped surface heat exchanger in the presence of a transverse magnetic field. In our case the gap between the blades and the device wall is narrow so lubrication theory approximations work for the flow. Steady isothermal flow of an electrically conducting Newtonian fluid is considered around a periodic array of pivoted scraper blade in a channel in which the lower wall is moving and the upper wall is at rest. Two-dimensional flow in the transverse section of a scraped surface heat exchanger is taken. Details of the flow properties, including the possible presence of regions of reversed flow under the blades, the forces on the blades and walls, and the fluxes of fluid above and below the blades are calculated. Graphic representation for involved flow parameters is also given.

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JONES, DEANA R., RICHARD K. GAST, PRAFULLA REGMI, GARRETT E. WARD, KENNETH E. ANDERSON, and DARRIN M. KARCHER. "Pooling of Laying Hen Environmental Swabs and Efficacy of Salmonella Detection." Journal of Food Protection 83, no. 6 (February 6, 2020): 943–50. http://dx.doi.org/10.4315/jfp-19-467.

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ABSTRACT Environmental testing for Salmonella Enteritidis is required for U.S. shell egg producers with ≥3,000 hens on a farm. The egg producer assumes all costs for the mandatory testing. According to the U.S. Food and Drug Administration (FDA) Egg Rule, either manure scraper or drag swabs can be collected according to published guidelines and requirements. The present study was undertaken to determine the efficacy of Salmonella detection with one-, two-, and four-swab pools of either manure scraper or drag swabs. Resistant isolates of Salmonella serovars Enteritidis (1,000 ppm of streptomycin), Heidelberg (200 ppm of nalidixic acid [NA]), Typhimurium (200 ppm of NA), and Kentucky (200 ppm of NA) were utilized. Low (approximately 8.4 CFU) and high (approximately 84 CFU) levels of inocula were introduced onto a single swab within a pool. Single flocks from each conventional cage (manure scraper swabs) and cage-free barn (drag swabs) were monitored throughout the study at the ages required under the FDA Egg Rule. The highest and most consistent recovery of inoculum was found in single swab samples. For low dose inocula, recovery of isolates was low from single manure scraper swabs (57.9 to 29.2%) and decreased as more swabs were added to the pool. Recovery of isolates from manure scraper swabs was higher for high dose inocula, although Salmonella Heidelberg was outcompeted by the naturally occurring flora and had the lowest rate of recovery among the isolates tested. One- and two-swab pools of drag swabs had similar rates of recovery at both low and high doses for Salmonella Enteritidis, Salmonella Heidelberg, and Salmonella Typhimurium. When Salmonella Enteritidis and Salmonella Kentucky were combined in an inoculum, Salmonella Enteritidis was recovered at a much higher rate than was Salmonella Kentucky for all types of swabs and doses of inocula. Pooling of two drag swabs allowed for similar detection of low and high dose Salmonella, but the pooling of manure scraper swabs decreased detection of low dose Salmonella. HIGHLIGHTS

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Wang, Yanping, and Shaoying Wang. "Coordinated Speed Planning Strategy of Scraper Conveyor and Shearer Based on Scraper Conveyor Loads Analysis." IOP Conference Series: Earth and Environmental Science 267 (June 8, 2019): 042044. http://dx.doi.org/10.1088/1755-1315/267/4/042044.

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Anbalagan, Sankarappan, Sundaram Dinakaran, and Muthukalingan Krishnan. "Life Cycle and Secondary Production of Four Species from Functional Feeding Groups in a Tropical Stream of South India." International Journal of Zoology 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/191059.

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This study focused on life strategies of species from functional feeding groups (FFGs) found in a tropical stream of the Sirumalai hills, South India. We examined the life cycle and secondary production of species of shredders (Lepidostoma nuburagangai), scrapers (Baetissp.), collectors (Choroterpes alagarensis), and predators (Neoperla biseriata). In addition, we studied the assemblage structure of functional feeding groups. We found the collectors occupied the highest percentage, followed in turn by scrapers, predators, and shredders. The diversity of FFGs was higher at riffle areas and assemblage with stream substrates differing in each functional group. An asynchronous life cycle was observed forBaetis,C. alagarensis, andN. biseriata, whileL. nuburagangaiwas found in four to five generations per year. We acquired data on secondary production of scraper species ofBaetis, which reached the highest values among all investigated species. This observation stresses the importance of scrapers as playing a key role in converting coarse particulate organic matter to fine particulate organic matter with low or high abundances of shredder population and maintaining the food chain in tropical streams.

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Journal articles on the topic 'Scraper'

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