Journal articles: 'Hill, conditions de'

1

Liu, Hu, and Wang. "Large Eddy Simulations of the Flow Fields over Simplified Hills with Different Roughness Conditions, Slopes, and Hill Shapes: A Systematical Study." Energies 12, no. 18 (September 4, 2019): 3413. http://dx.doi.org/10.3390/en12183413.

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Turbulent flow fields over topographies are important in the area of wind energy. The roughness, slope, and shape of a hill are important parameters affecting the flow fields over topographies. However, these effects are always examined separately. The systematic investigations of these effects are limited, the coupling between these effects is still unrevealed, and the turbulence structures as a function of these effects are still unclear. Therefore, in the present study, the flow fields over twelve simplified isolated hills with different roughness conditions, slopes, and hill shapes are examined using large eddy simulations. The mean velocities, velocity fluctuations, fractional speed-up ratios, and visualizations of the turbulent flow fields are presented. It is found that as the hill slope increases, the roughness effects become weaker, and the roughness effects will further weaken as the hill changes from 3D to 2D. In addition, the fractional speed-up ratio at the summit of rough hills can even reach to three times as large as that over the corresponding smooth hills. Furthermore, the underestimation of the ratios of spanwise fluctuation to the streamwise fluctuation by International Electrotechnical Commission (IEC) 61400-1 is quite obvious when the hill shape is 3D. Finally, coherent turbulence structures can be identified for smooth hills, and as the hill slope increases, the coherent turbulence structures will experience clear evolutions. After introducing the ground roughness, the coherent turbulence structures break into small eddies.

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Barker, J. D., C. Smith, and N. Bateman. "Crossbred Ewes for Hill Conditions." BSAP Occasional Publication 10 (1985): 164. http://dx.doi.org/10.1017/s0263967x00030950.

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Snyder, William H., Roger S. Thompson, Robert E. Eskridge, Robert E. Lawson, Ian P. Castro, J. T. Lee, Julian C. R. Hunt, and Yasushi Ogawa. "The structure of strongly stratified flow over hills: dividing-streamline concept." Journal of Fluid Mechanics 152 (March 1985): 249–88. http://dx.doi.org/10.1017/s0022112085000684.

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In stably stratified flow over a three-dimensional hill, we can define a dividing streamline that separates those streamlines that pass around the hill from those that pass over the hill. The height Hs of this dividing streamline can be estimated by Sheppard's simple energy argument; fluid parcels originating far upstream of a hill at an elevation above Hs have sufficient kinetic energy to rise over the top, whereas those below Hs must pass around the sides. This prediction provides the basis for analysing an extensive range of laboratory observations and measurements of stably stratified flow over a variety of shapes and orientations of hills and with different upwind density and velocity profiles. For symmetric hills and small upwind shear, Sheppard's expression provides a good estimate for Hs. For highly asymmetric flow and/or in the presence of strong upwind shear, the expression provides a lower limit for Hs. As the hills become more nearly two-dimensional, these experiments become less well defined because steady-state conditions take progressively longer to be established. The results of new studies are presented here of the development of the unsteady flow upwind of two-dimensional hills in a finite-length towing tank. These measurements suggest that a very long tank would be required for steady-state conditions to be established upstream of long ridges with or without small gaps and cast doubt upon the validity of previous laboratory studies.

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Jia, Zhen Zhen, and Tao Feng. "Analysis on Explosion Characteristics of Coal Gangue Hills." Advanced Materials Research 955-959 (June 2014): 924–27. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.924.

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In the process of the coal gangue hill explosion, a lot of harmful gases can be released, which seriously pollutes the atmospheric environment and is harmful to people’s health; meanwhile, equipments and the surrounding buildings can also be destroyed, which brings huge economic losses and casualties. In addition, social problems caused by coal gangue hills will become a thorny problem for coal enterprises. Therefore, the influencing factors on the coal gangue hill explosion, the explosion characteristics and laws, and the spontaneous combustion process of the coal gangue hill are analyzed; the coal gangue hill explosion are discussed from the arch shell theory, the bottom air leakage and oxygen supply, rainfall, detonating gas explosion, and chain reaction; the conditions, influencing factors and characteristics of the coal gangue hill explosion are obtained.

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Sun, Menghan, and Hui Qi. "Scattering of Antiplane SH Waves by Complex Landforms." Shock and Vibration 2021 (August 5, 2021): 1–21. http://dx.doi.org/10.1155/2021/9997230.

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The multiple scattering of SH waves by isosceles triangular hill, semicircle depression, and isosceles trapezoidal hill in the solid half-space is studied. The complex model is divided into multiple subdomains by using the region matching method, then the wave functions in each subdomain are constructed by using the fractional-order Bessel function, and finally, the infinite algebraic equations for solving the unknown coefficients in the wave function are established by using the multipolar coordinate technique and the complex function method according to the boundary conditions. Fourier series is used to solve the unknown undetermined coefficients. The results show that due to the multiple reflections of the incident wave between complex landforms, surface displacement amplitude is affected by the incident angle, incident frequency, and the distance between the isosceles triangular hill, semicircle depression, and isosceles trapezoidal hill. It is found that when the incident frequency increases, there is a certain amplification effect between the hills and the depression. When the wave is incident horizontally, there is a certain “barrier” effect between hills and depression, and when the distance between the hills and depression reaches a certain level, the “barrier” effect will reach a stable value.

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Oladosu, Yusuff, M. Y. Rafii, Usman Magaji, Norhani Abdullah, Gous Miah, Samuel C. Chukwu, Ghazali Hussin, Asfaliza Ramli, and Isiaka Kareem. "Genotypic and Phenotypic Relationship among Yield Components in Rice under Tropical Conditions." BioMed Research International 2018 (July 15, 2018): 1–10. http://dx.doi.org/10.1155/2018/8936767.

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The associations among yield-related traits and the pattern of influence on rice grain yield were investigated. This evaluation is important to determine the direct and indirect effects of various traits on yield to determine selection criteria for higher grain yield. Fifteen rice genotypes were evaluated under tropical condition at five locations in two planting seasons. The experiment was laid out in a randomized complete block design with three replications across the locations. Data were collected on vegetative and yield components traits. The pooled data based on the analysis of variance revealed that there were significant differences (p<0.001) among the fifteen genotypes for all the characters studied except for panicle length and 100-grain weight. Highly significant and positive correlations at phenotypic level were observed in grain weight per hill (0.796), filled grains per panicle (0.702), panicles per hill (0.632), and tillers per hill (0.712) with yield per hectare, while moderate positive correlations were observed in flag leaf length to width ratio (0.348), days to flowering (0.412), and days to maturity (0.544). By contrast, unfilled grains per panicle (-0.225) and plant height (-0.342) had a negative significant association with yield per hectare. Filled grains per panicle (0.491) exhibited the maximum positive direct effect on yield followed by grain weight per hill (0.449), while unfilled grain per panicle (-0.144) had a negative direct effect. The maximum indirect effect on yield per hectare was recorded by the tillers per hill through the panicles per hill. Therefore, tillers per hill, filled grains per panicle, and grain weight per hill could be used as selection criteria for improving grain yield in rice.

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Goddard, P. J., A. R. Fawcett, and A. J. Macdonald. "The adaptation of hill lambs to housing conditions." Applied Animal Behaviour Science 58, no. 3-4 (July 1998): 331–39. http://dx.doi.org/10.1016/s0168-1591(97)00147-0.

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8

Xiu, Da. "Research on Reservoir Conditions of Buried Hill Reservoirs." IOP Conference Series: Earth and Environmental Science 252 (July 9, 2019): 052011. http://dx.doi.org/10.1088/1755-1315/252/5/052011.

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Narjisse, Amahjour, and Khamlichi Abdellatif. "Assessment of RANS turbulence closure models for predicting airflow in neutral ABL over hilly terrain." International Review of Applied Sciences and Engineering 12, no. 3 (July 21, 2021): 238–56. http://dx.doi.org/10.1556/1848.2021.00264.

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AbstractImplementing wind farms in heights of a hilly terrain where wind speed is expected to be large may be viewed as a means to increase wind energy production without occupying fertile lands. Micro sitting of a wind farm in these conditions can gain dramatically from CFD simulation of fluid flow in the ABL above complex topography. However, this issue still poses tough challenges regarding the turbulence model to be used and the way to operate the near wall treatment in the presence eventually of separation. In this work, prediction capacity of RANS turbulence models was studied for a typical hill under the assumption of steady state and incompressible airflow regime in neutral ABL. Two models were analyzed by using COMSOL Multiphysics software packages. These included standard , and shear-stress transport . The most up-to-date procedures dedicated to near wall treatment were applied along with refined closer coefficients adjusted for the particular case of ABL. Considering wind tunnel test data, performance of the previous models was discussed in terms of converging mesh, computational time, reattachment point position and propensity of the model to retrieve the right level of turbulence flow in conditions of neutral stratifications. Then, a numerical simulation of the turbulent airflow over two slopes shapes of the symmetry hill by the validation of the experimental data has been then carried out. Both turbulence models agree well with air-velocity tested windward of the hills H3 and H5. Therefore, it was found that the standard model performs very well at the different positions of the low slope hill, and at the summit of a steep hill, but it over-predicts wind speed close to the wall, which requires an improvement of the near-wall treatment. However, the model in neutral case of the ABL was given consistent simulation results with experimental data for prediction of the flow separation and recirculation region at the leeward side of a steep hill, whereas standard model under the neutral condition and the model by using standard coefficients were failed to predict accurately detailed characteristics of recirculation region process.

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Dawson, L. E. R., and A. F. Carson. "The effects of genotype of crossbred ewes, evaluated under lowland conditions, on lamb output." Proceedings of the British Society of Animal Science 2000 (2000): 67. http://dx.doi.org/10.1017/s1752756200000685.

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Lowland sheep farmers in Northern Ireland depend heavily on the hill sector for replacement breeding ewes. Thus changes in the genetics of the ewes and rams used in the hills are likely to have major implications on the performance of lowland breeding ewes. Crossbred females were produced in the study by Carson et al. (2000) as a result of crossing Scottish Blackface and Wicklow Cheviot ewes with a range of sire breeds. The objective of this study was to provide information on the productivity of these crossbred females for lowland producers.

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Dey, Sudip, Chandrani Debbarma, Prasamita Sarkar, and Sushmita Paul. "Geo-electrical mapping and groundwater potential zoning in some selected pockets of Baromura hill of Tripura (India)." Journal of Applied and Natural Science 2, no. 2 (December 1, 2010): 207–12. http://dx.doi.org/10.31018/jans.v2i2.121.

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Baromura hill of Tripura is characterised by complex geology and very rugged landform. Water scarcity is a very general problem for the remote hilly villages of this area. Thus groundwater is considered as one of the most valuable natural resources in hilly villages of Baromura hill. The present study aims to prepare small area survey based geo-electrical mapping for understanding groundwater condition in some selected pockets of the study area. For that purpose one hill slope and one trough shaped low land (locally known as lunga) was selected. Soil resistivity meter was used for electrical survey. A circle plot was prepared for geo-electrical survey on the basis of which geo-electrical maps were drawn. In the studied hill slope morphology four sectors of ground water conditions were observed according to their electrical resistivity character namely shallowest zone, medium zone, deep zone and very deep zone. The trough shaped low land (lunga) is characterised by comparatively shallower condition of groundwater and it was divided into five classes namely near surface water, very shallow zone, shallow zone, medium shallow zone and medium zone. Though the depth of the water bearing strata cannot be detected by this method it is very suitable for understanding the groundwater potential zones in remote places like present study area.

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12

Highsmith, M. Jason, Jason T. Kahle, Rebecca M. Miro, and Larry J. Mengelkoch. "Ramp descent performance with the C-Leg and interrater reliability of the Hill Assessment Index." Prosthetics and Orthotics International 37, no. 5 (January 17, 2013): 362–68. http://dx.doi.org/10.1177/0309364612470482.

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Background: Transfemoral amputees have decreased ability to descend ramps and hills. The Hill Assessment Index quantifies transfemoral amputee ramp performance, but interrater reliability has not been assessed. Objectives: To determine whether C-Leg use improves hill descent gait and evaluate the Hill Assessment Index’s interrater reliability. Methods: Twenty-one transfemoral amputees descended a ramp while timed and video recorded, using their nonmicroprocessor prosthetic knee. Subjects were fitted and accommodated with a C-Leg and retested. Test times were compared, and ramp performances were independently reviewed using the Hill Assessment Index by two raters. Hill Assessment Index scores were compared between knee conditions within raters for performance and between raters to assess the Hill Assessment Index’s interrater reliability. Results: Mean Hill Assessment Index scores were greater for C-Leg compared to nonmicroprocessor prosthetic knee for both raters. C-Leg resulted in faster ramp descent. Strong correlations resulted between raters on Hill Assessment Index scores for nonmicroprocessor prosthetic knee (intraclass correlation coefficient = 0.97) and C-Leg (intraclass correlation coefficient = 0.99). Conclusions: C-Leg improves Hill Assessment Index ramp descent performance and time. In descent quality, C-Leg offers the possibility of eliminating assistive device use and/or improving step length in the absence of an assistive device. C-Leg resulted in 23% gait speed increase during ramp descent. The Hill Assessment Index had very good interrater reliability but should be assessed for intrarater reliability, minimal detectable change, and validity. Clinical relevance Transfemoral amputees have difficulty ambulating on ramps. While the C-Leg has been shown to improve ramp descent, this has not been confirmed, and the Hill Assessment Index has not been studied for reliability. This study confirms that the C-Leg improves ramp descent performance and the Hill Assessment Index’s interrater reliability.

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13

Peng, Xing Qian, and Ling Lin Shi. "Analysis of Wind Load Effect on the Roof of Low-Rise Building in the Mountain Terrain." Advanced Materials Research 382 (November 2011): 176–82. http://dx.doi.org/10.4028/www.scientific.net/amr.382.176.

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The wind conditions of the low-rise building in the mountain terrain are different because they have the characteristics of different landforms. When the typhoon comes, the possibility of structural damage is increasing by the negative effects of wind in the special topography. By establishing a sine function of outline of the hill, this paper makes a CFD(Computational Fluid Dynamics) numerical simulation about the low-rise building around the hills with four different height. Using ANSYS-CFX software as calculating platform, it put forward the roof wind load effect of the Low-rise building by study the characteristics of the hill, the law of wind pressure distribution and the influence to roof wind load by wind direction and the high of the hill, the conclusions which can provide a reference for wind-resistant design have practical significance.

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14

Lucas, Robin L., and Catherine A. Lee. "Roles of hilC and hilD in Regulation of hilA Expression in Salmonella enterica Serovar Typhimurium." Journal of Bacteriology 183, no. 9 (May 1, 2001): 2733–45. http://dx.doi.org/10.1128/jb.183.9.2733-2745.2001.

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ABSTRACT Sequences between −332 and −39 upstream of the hilApromoter are required for repression of hilA. An unidentified repressor is thought to bind these upstream repressing sequences (URS) to inhibit hilA expression. Two AraC-like transcriptional regulators encoded on Salmonellapathogenicity island 1 (SPI1), HilC and HilD, bind to the URS to counteract the repression of hilA. The URS is required for regulation of hilA by osmolarity, oxygen, PhoP/PhoQ, and SirA/BarA. Here, we show that FadD, FliZ, PhoB, and EnvZ/OmpR also require the URS to regulate hilA. These environmental and regulatory factors may affect hilA expression by altering the expression or activity of HilC, HilD, or the unknown repressor. To begin investigating these possibilities, we tested the effects of environmental and regulatory factors on hilC andhilD expression. We also examined hilAregulation when hilC or hilD was disrupted or expressed to a high level. Although hilC is regulated by all environmental conditions and regulatory factors that modulatehilA expression, hilC is not required for the regulation of hilA by any conditions or factors except EnvZ/OmpR. In contrast, hilD is absolutely required forhilA expression, but environmental conditions and regulatory factors have little or no effect on hilDexpression. We speculate that EnvZ/OmpR regulates hilA by altering the expression and/or activity of hilC, while all other regulatory conditions and mutations regulate hilA by modulating hilD posttranscriptionally. We also discuss models in which the regulation of hilA expression is mediated by modulation of the expression or activity of one or more repressors.

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Guo, Dong-Peng, Peng Zhao, Ran Wan, Ren-Tai Yao, and Ji-Min Hu. "Numerical Simulation of the Flow Field and Pollutant Dispersion around a Hill under Different Thermal Stratifications." Journal of Applied Meteorology and Climatology 59, no. 1 (January 2020): 47–64. http://dx.doi.org/10.1175/jamc-d-18-0308.1.

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AbstractThis paper applied a commercial computational fluid dynamics code, STAR-CD, with the renormalization group k–ε turbulence model to simulate the flow and dispersion of contaminants released from a source on the windward side of a hill under different thermal stratifications. In the wake region, the influence of atmospheric stratification on the flow field is inconspicuous under neutral and unstable conditions because of the effect of mechanical disturbance. However, this influence becomes slightly conspicuous under stable conditions. When atmospheric stratification is stable, in the range of z/H < 1.0 (where z is height above the surface and H is height of the hill), the velocity deficits are smaller than those under neutral and unstable conditions. The maximum turbulence kinetic energy (TKE) appears in the wake regions, and the variation in TKE is significantly lower than that under neutral and unstable conditions. When atmospheric stratification is unstable, the vertical and horizontal spread of the plume is slightly greater than that under neutral and stable conditions and the maximum concentration is less than that under neutral conditions. When the Froude number is large (~11; Brunt–Väisälä frequency = 0.52), atmospheric stratification is slightly stable, the structure of flow around the hill is generally similar to that under neutral conditions, and the high-concentration regions are large on the windward side of the hill. Smaller high-concentration regions just appear on the windward side of the hill under unstable conditions. The pollutant concentrations in the wake region of the hill increase as a result of the effect of thermal stability, and the vertical spreading range of the plume along the downwind axis (x axis) is larger than that under neutral and stable conditions.

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Pandey, V., K. Pandey H, D. Dayal, C. Joshi U, T. Pant, and Z. Ahmed. "Studies on antioxidant constituents of some domesticated capsicums in the middle hill conditions of western Himalayas." Horticultural Science 36, No. 1 (February 11, 2009): 26–30. http://dx.doi.org/10.17221/18/2008-hortsci.

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The objective of this study was to determine some cultivars suitable for their antioxidant constituents, which can further be used in breeding programmes to breed superior varieties and F1 for higher quality attributes. Thirty cultivars of domesticated capsicums were grown and analyzed during 2006–2007; they showed significant variation in their ascorbic acid and capsaicinoids contents. On the basis of ascorbic acid, the rank order of cultivars was PBC-926 > Chilli Long Black > HC-201 > KT OV > Local D-2. On the basis of capsaicinoids content, five top cultivars were selected, namely DARL-210 > Naga Jalokia > Red Sabina > CO-6-1 > Chilli Long Black.

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Křížek, Marek. "Surface and Undersurface Phenomena in the Čecher Hill in the Hostýnské vrchy Hills." Geografie 104, no. 3 (1999): 201–8. http://dx.doi.org/10.37040/geografie1999104030201.

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The author describes surface and undersurface landforms in the Čecher Hill (the Outer Western (Flysch) Carpathians) and outlines their origin and development. The main part of the article focuses on periglacial and pseudokarst (above all a pseudokarst cave in the Čecher Hill) landforms in this area. It also describes periglacial processes in the Pleistocene and the processes of humid character in the Holocene, which formed these landforms. The author takes notice of the relationship between landforms and geological conditions in the area.

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Chatzipanagiotidis, A., and D. Olivari. "Pollutant dispersal downstream of a hill in different wind conditions." Journal of Wind Engineering and Industrial Aerodynamics 64, no. 2-3 (November 1996): 233–48. http://dx.doi.org/10.1016/s0167-6105(96)00064-5.

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Hu, Xijun, Yuwei Ou, and Penghui Wang. "Hill-type formula for Hamiltonian system with Lagrangian boundary conditions." Journal of Differential Equations 267, no. 4 (August 2019): 2416–47. http://dx.doi.org/10.1016/j.jde.2019.03.018.

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Raposo, J. R., S. Cabiddu, D. X. Viegas, M. Salis, and J. Sharples. "Experimental analysis of fire spread across a two-dimensional ridge under wind conditions." International Journal of Wildland Fire 24, no. 7 (2015): 1008. http://dx.doi.org/10.1071/wf14150.

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Results from a laboratory-scale investigation of a fire spreading on the windward face of a triangular-section hill of variable shape with wind perpendicular to the ridgeline are reported. They confirm previous observations that the fire enlarges its lateral spread after reaching the ridgeline, entering the leeward face with a much wider front. Reference fire spread velocities were measured and analysed, putting in evidence the importance of the dynamic effect due to flow velocity and its associated horizontal-axis separation vortex strength without dependence on hill geometry. Similar parameters estimated from three forest fires compared favourably with the laboratory-scale measurements.

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Urbančič, Tilen, Oskar Sterle, and Klemen Kregar. "An Improved Approach for the Control Measurements of a Ski-Flying Hill Inrun: A Case Study of Planica." Sensors 20, no. 9 (May 8, 2020): 2680. http://dx.doi.org/10.3390/s20092680.

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Ski jumping hills should be prepared for competitions in accordance with project documentation in order to ensure safe and fair conditions for competitors. Geodesy/surveying is essential for guiding preparations and controlling the actual shape of the hill. In this article, we present a methodology for the control measurements and preparation of an inrun for a ski-flying hill in Planica. On each side of the track, there is metal tube that guides the trolley, which mills tracks into the ice. A special platform containing three measuring prisms was designed to control the position of the tubes. The proposed method was thoroughly analyzed in terms of its measurement quality and compared to previously used methodologies. The empirical results suggest that our proposed platform provides inrun geometry with a higher quality than previously used methods.

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Neumayr, P., J. R. Ridley, and D. I. Groves. "sPhysicochemical conditions of fluid–wall rock interaction at amphibolite-facies conditions in two Archean hydrothermal gold deposits in the Mt. York District, Pilbara Craton, Western Australia." Canadian Journal of Earth Sciences 32, no. 7 (July 1, 1995): 993–1016. http://dx.doi.org/10.1139/e95-083.

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Synamphibolite facies Archean gold mineralization in the Mt. York District, Pilbara Craton, Western Australia, is hosted in metamorphosed banded iron formation (Main Hill–Breccia Hill prospect), amphibolites, and ultramafic schists (Zakanaka prospect). Mineralization at Main Hill occurs in quartz breccias with sulfide matrices and in altered wall rock adjacent to quartz–biotite–amphibole ± clinopyroxene veins. Alteration associated with quartz veins is zoned, with biotite—pyrrhotite vein selvedges and a distal calcic-amphibole, arsenopyrite–lôllingite zone. Hydrothermal biotite and actinolite have highest Mg/(Mg + Fe) ratios where associated with abundant sulfarsenides in the distal alteratin zone. Whole-rock geochemical analyses and calculated metasomatic reactions indicate the addition of K, Al, S, As, Au, Ag, and Ni during hydrothermal alteration. Mineralization at Zakanaka is characterized by a broad wall rock alteration halo of biotite–amphibole, and zoned quartz–calc silicate veins proximal to ore. Wall rock adjacent to the veins contains pyrrhotite, pyrite, and gold. The alteration is explained by K-metasomatism distal to mineralization and K and Ca metasomatism proximal to mineralization. Balanced metasomatic reactions and mass-balance calculations indicate addition of K and depletion of Na, Ca, Mg, and Fe in distal alteration zones and addition of K, Ca, Mg, Fe, and Ti in proximal zones. Gold precipitation at both prospects occurred through loss of S, and possibly As, from the ore fluid during sulfidation reactions with Fe-rich amphiboles and biotites to form Mg-enriched equivalents and sulfarsenides. Changes in the oxidation state of the ore fluid may have enhanced gold precipitation, though pH changes are unlikely to have been important. The controls on mineralization are thus similar to those at many lower temperature, mesothermal deposits. The lack of consistently increasing Mg ratios of calc-silicate phases with increasing intensity of alteration and sulfidation at Main Hill may be the result of coupled substitutions in amphiboles and biotites during infiltration of a fluid with high-S, but low-As, activities.

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Gosme, Marie, and Philippe Lucas. "Disease Spread Across Multiple Scales in a Spatial Hierarchy: Effect of Host Spatial Structure and of Inoculum Quantity and Distribution." Phytopathology® 99, no. 7 (July 2009): 833–39. http://dx.doi.org/10.1094/phyto-99-7-0833.

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Spatial patterns of both the host and the disease influence disease spread and crop losses. Therefore, the manipulation of these patterns might help improve control strategies. Considering disease spread across multiple scales in a spatial hierarchy allows one to capture important features of epidemics developing in space without using explicitly spatialized variables. Thus, if the system under study is composed of roots, plants, and planting hills, the effect of host spatial pattern can be studied by varying the number of plants per planting hill. A simulation model based on hierarchy theory was used to simulate the effects of large versus small planting hills, low versus high level of initial infections, and aggregated versus uniform distribution of initial infections. The results showed that aggregating the initially infected plants always resulted in slower epidemics than spreading out the initial infections uniformly. Simulation results also showed that, in most cases, disease epidemics were slower in the case of large host aggregates (100 plants/hill) than with smaller aggregates (25 plants/hill), except when the initially infected plants were both numerous and spread out uniformly. The optimal strategy for disease control depends on several factors, including initial conditions. More importantly, the model offers a framework to account for the interplay between the spatial characteristics of the system, rates of infection, and aggregation of the disease.

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Gao, Wan Fei, and Man Lin Zhu. "Preliminary Exploration of Ecological Landscape Construction on Hill and Gully Regions of Loess Plateau." Applied Mechanics and Materials 584-586 (July 2014): 621–24. http://dx.doi.org/10.4028/www.scientific.net/amm.584-586.621.

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For the research on hill and gully landscape of Loess Plateau, to prevent water loss and soil erosion and improve the ecological environment, the paper analyzes the construction of ecological landscape from the large range to small, puts focus on small watershed and hilly gully, and chooses Baiyun mountain demonstrate area as a case to present its landscape planning and design. The research and its related activities integrated and coordinated multidisciplinaries, like the hydraulic engineering, civil engineering and other disciplines. The project constructed dams, transferred and stored water in the gully which has better conditions, achieved good results. Due to the characteristics of hill and gully regions of Loess Plateau, its ecological environment construction must be closely combined with other disciplinaries. Moreover, it is better to construct different demonstrate areas to well improve the research on macro ecological environment.

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Sheha, A. M., Haytham Mostafa El-Shahed, and Abd El Nabi Hamed Mohamed Diab. "Response of Watermelon Pulp (Citrullus colocynthoides) to Intercropped Maize (Zea mays L.) With Plants Distributions Under Different Nitrogen Fertilization Levels." Journal of Agricultural Science 12, no. 8 (July 15, 2020): 212. http://dx.doi.org/10.5539/jas.v12n8p212.

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Two field experiments were carried out at the Experimental Farm of Gemmeiza Agriculture Research Station, Agricultural Research Center (ARC), Egypt after 2018 and 2019 summer growing seasons to determine the effect of intercropping pattern of yellow maize hybrid (single cross 168: “SC 168”) with watermelon pulp at three plant distributions (20 cm between hills and one plant/hill, 40 cm between hills and two plants/hill and 60 cm between hills and three plants/hill) and different levels of nitrogen fertilizer (25, 50, 75 and 100% of the recommended dose “120 kg N fad-1”) as well as their interactions on maize and watermelon pulp growth, yield and its attributes as well as competitive relationships and yield advantages. The experiments were carried out in split-plot design with four replicates. The main-plots were assigned to plant distributions of maize, the sub-plots were allocated to levels of nitrogen fertilizer for maize. The obtained results showed that planting maize plants on one side of terraces of 140 cm width with 20 cm between hills and leaving one plant/hill and planting watermelon pulp on the other side of the terraces produced the highest values of plant height, ear height, number of kernels row-1, 100-kernel weight and grain yield fad-1, at the same time the lowest values of ear leaf area, ear length, ear diameter and number of rows ear-1 of maize as well as the lowest values of growth, yield and its attributes of watermelon pulp during the both seasons. Mineral fertilizing maize plants with 75% of the recommended dose (90 kg N/fad) and watermelon pulp with the recommended dose produced the highest values of all studied growth characters, yield and its attributes of maize and watermelon pulp in both seasons. The highest values of land equivalent ratio (LER), relative crowding coefficient (RCC), area time equivalent ratio (ATER), land equivalent coefficient (LEC), aggressivity index (AI), monetary advantage index (MAI), actual yield (L.E.) of watermelon, Total income (L.E.) and economic return (L.E.) were obtained from planting maize plants on one side of terraces of 140 cm width with 60 cm between hills and leaving three plants/hill and planting watermelon pulp on the other side of the terraces besides fertilizing maize plants with 75% of the recommended dose (90 kg N/fad) and watermelon pulp with the recommended dose in both seasons. It can be recommended that planting maize on 60 cm between hills and leaving three plants/hill and planting watermelon pulp on the other side of the terraces besides fertilizing maize plants with 90 kg N/fad and watermelon pulp with the recommended dose to obtain the maximum values growth, yield and its attributes of watermelon pulp and competitive relationships and yield advantages of both crops under the climates conditions of Middle Delta, Egypt.

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Romakkaniemi, Sami, Zubair Maalick, Antti Hellsten, Antti Ruuskanen, Olli Väisänen, Irshad Ahmad, Juha Tonttila, Santtu Mikkonen, Mika Komppula, and Thomas Kühn. "Aerosol–landscape–cloud interaction: signatures of topography effect on cloud droplet formation." Atmospheric Chemistry and Physics 17, no. 12 (June 30, 2017): 7955–64. http://dx.doi.org/10.5194/acp-17-7955-2017.

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Abstract. Long-term in situ measurements of aerosol–cloud interactions are usually performed in measurement stations residing on hills, mountains, or high towers. In such conditions, the surface topography of the surrounding area can affect the measured cloud droplet distributions by increasing turbulence or causing orographic flows and thus the observations might not be representative for a larger scale. The objective of this work is to analyse, how the local topography affects the observations at Puijo measurement station, which is located in the 75 m high Puijo tower, which itself stands on a 150 m high hill. The analysis of the measurement data shows that the observed cloud droplet number concentration mainly depends on the cloud condensation nuclei (CCN) concentration. However, when the wind direction aligns with the direction of the steepest slope of the hill, a clear topography effect is observed. This finding was further analysed by simulating 3-D flow fields around the station and by performing trajectory ensemble modelling of aerosol- and wind-dependent cloud droplet formation. The results showed that in typical conditions, with geostrophic winds of about 10 m s−1, the hill can cause updrafts of up to 1 m s−1 in the air parcels arriving at the station. This is enough to produce in-cloud supersaturations (SSs) higher than typically found at the cloud base of ∼ 0.2 %), and thus additional cloud droplets may form inside the cloud. In the observations, this is seen in the form of a bimodal cloud droplet size distribution. The effect is strongest with high winds across the steepest slope of the hill and with low liquid water contents, and its relative importance quickly decreases as these conditions are relaxed. We therefore conclude that, after careful screening for wind speed and liquid water content, the observations at Puijo measurement station can be considered representative for clouds in a boreal environment.

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Kamran, Muhammad Adeel, and Tahira Shamshad. "Impacts of Hill Torrents’ Management on Socio-Economic Conditions of Arid Land Farmers: a Case Study of Tehsil D.G. Khan." Asian Journal of Humanity, Art and Literature 2, no. 1 (June 30, 2015): 29–36. http://dx.doi.org/10.18034/ajhal.v2i1.292.

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The study conducted in arid areas of Dera Ghazi Khan occasionally affected by hill torrents (Suri-Lund, Vidore, Sakhi-Sarwar, Mithawan) coming from Koh-e-Suleman range. The study found that hill torrent water is used for agriculture, domestic and livestock. The management of this water significantly affects on income, crop yield, soil fertility, health conditions and living standard of farmers. The local cost effective methods to store this water include wah, dubba and bundh but most of water is wasted as they are insufficient. The water distribution mechanism fosters cooperation and helps to form new relations with co-farmers. The study suggested that government and NGOs should help people to construct concrete diversions, bundhs, ponds and dams to manage hill torrent water.

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Shi, Wen Pu. "Scattering of SH-Waves to Semi-Cylindrical Canyon and Rectangular Elastic Hill on the Ground." Advanced Materials Research 610-613 (December 2012): 2544–51. http://dx.doi.org/10.4028/www.scientific.net/amr.610-613.2544.

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Wave function expansion method and Green function method were employed to study thescattering problem of SH-waves to the semi-cylindrical canyon and rectangular hill on the gr ound. First, the displacements in the half space and rectangular hill were given which can santisfy the stress-free conditions on the free boundaries. Then, the first kind of Fredholm integration equation of the unknown distribution stress was obtained by using the displacement conditions on the common boundary between the half-space and the rectangular hill, and Gauss-Legendre integration formula was used to solve the equation. The given example results show the feasibility and practicability of the method here.

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Hepp, C., I. Valentine, J. Hodgson, A. G. Gillingham, and P. D. Kemp. "Effects of grass suppression on legume abundance during two contrasting seasons on a summer-dry hill country site." NZGA: Research and Practice Series 11 (January 1, 2003): 123–29. http://dx.doi.org/10.33584/rps.11.2003.3005.

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The low level of legumes in New Zealand hill pastoral systems is a recognized problem that is likely to affect sustainability. The relative importance of the factors that cause low legume abundance has not been sufficiently tested, especially on dry hill country. This paper reports the effects of grass suppression in two contrasting years in a summer-dry hill country site on the east coast of the North Island. Suppressing grass with haloxyfop herbicide (Gallant) in late autumn increased legume abundance by > 25% in both years, but the response patterns were strongly influenced by soil moisture status. Moist late spring and summer conditions produced 34% more legume growth in both Â± herbicide treatments. Residual effects of grass suppression favoured white clover over subterranean clover growth under moist seasonal conditions. The control of grass growth in these hill swards improved legume abundance, but the overriding factor affecting legume content in the pasture was the level of soil moisture. Key words: grass suppression, haloxyfop herbicide, hill country, legume abundance, soil moisture, subterranean clover, summer-dry, white clover

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Mattey, Beth. "A Day on the Hill." NASN School Nurse 32, no. 4 (July 2017): 223–25. http://dx.doi.org/10.1177/1942602x17712456.

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This article describes the author’s advocacy experience at a press briefing on Capitol Hill. At stake is the continuation of Medicaid and Children’s Health Insurance Program-funded health insurance to our most vulnerable children—those living in poverty and those with chronic health conditions. Current legislation proposes to impose block grants or per capita caps on federal funding for Medicaid and will put the reauthorization of the Children’s Health Insurance Program at risk. Schools stand to lose over 4 billion dollars in reimbursement for services that students need to succeed in school.

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Sharma, Deepa, Sanjeev Kumar Banyal, and Y. R. Shukla. "Performance of brinjal genotypes under low hill conditions of Himachal Pradesh." Agricultural Research Journal 53, no. 2 (2016): 268. http://dx.doi.org/10.5958/2395-146x.2016.00050.8.

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Sharma, Deepa, and Sanjeev Kumar Banyal. "Evaluation of brinjal genotypes under low hill conditions of Himachal Pradesh." Progressive Horticulture 48, no. 2 (2016): 194. http://dx.doi.org/10.5958/2249-5258.2016.00032.4.

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Gautam, Arstu, Achyut Das, K. Ramachandra Rao, and Geetam Tiwari. "Estimation of PCE values for hill roads in heterogeneous traffic conditions." Transportation Letters 10, no. 2 (June 16, 2016): 83–91. http://dx.doi.org/10.1080/19427867.2016.1190884.

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Lacy, Sarah A. "The oral pathological conditions of the Broken Hill (Kabwe) 1 cranium." International Journal of Paleopathology 7 (December 2014): 57–63. http://dx.doi.org/10.1016/j.ijpp.2014.06.005.

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Bazley, Norman W., and Thomas Mrziglod. "Global bifurcation for a special Hill equation with nonlinear boundary conditions." ZAMP Zeitschrift f�r angewandte Mathematik und Physik 43, no. 2 (March 1992): 328–34. http://dx.doi.org/10.1007/bf00946634.

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Sajwan, Paramjeet, Girish Sharma, Ashok Yadav, and Kiran Thakur. "Genetic diversity of walnut for horticultural traits under mid hill conditions." Indian Journal of Horticulture 78, no. 2 (2021): 142–48. http://dx.doi.org/10.5958/0974-0112.2021.00020.7.

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Resnick, Sidney, and Cătălin Stărică. "Smoothing the Hill Estimator." Advances in Applied Probability 29, no. 01 (March 1997): 271–93. http://dx.doi.org/10.1017/s0001867800027889.

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For sequences of i.i.d. random variables whose common tail 1 – F is regularly varying at infinity wtih an unknown index –α < 0, it is well known that the Hill estimator is consistent for α–1 and usually asymptotically normally distributed. However, because the Hill estimator is a function of k = k(n), the number of upper order statistics used and which is only subject to the conditions k →∞, k/n → 0, its use in practice is problematic since there are few reliable guidelines about how to choose k. The purpose of this paper is to make the use of the Hill estimator more reliable through an averaging technique which reduces the asymptotic variance. As a direct result the range in which the smoothed estimator varies as a function of k decreases and the successful use of the esimator is made less dependent on the choice of k. A tail empirical process approach is used to prove the weak convergence of a process closely related to the Hill estimator. The smoothed version of the Hill estimator is a functional of the tail empirical process.

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Resnick, Sidney, and Cătălin Stărică. "Smoothing the Hill Estimator." Advances in Applied Probability 29, no. 1 (March 1997): 271–93. http://dx.doi.org/10.2307/1427870.

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For sequences of i.i.d. random variables whose common tail 1 – F is regularly varying at infinity wtih an unknown index –α < 0, it is well known that the Hill estimator is consistent for α–1 and usually asymptotically normally distributed. However, because the Hill estimator is a function of k = k(n), the number of upper order statistics used and which is only subject to the conditions k →∞, k/n → 0, its use in practice is problematic since there are few reliable guidelines about how to choose k. The purpose of this paper is to make the use of the Hill estimator more reliable through an averaging technique which reduces the asymptotic variance. As a direct result the range in which the smoothed estimator varies as a function of k decreases and the successful use of the esimator is made less dependent on the choice of k. A tail empirical process approach is used to prove the weak convergence of a process closely related to the Hill estimator. The smoothed version of the Hill estimator is a functional of the tail empirical process.

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Wang, Xue Lian, Man Xu, Jing Xiao, and Ran Guo. "Research on Optimization Scheduling Problem in Complex Conditions." Applied Mechanics and Materials 519-520 (February 2014): 1520–24. http://dx.doi.org/10.4028/www.scientific.net/amm.519-520.1520.

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The paper presented an optimization scheduling problem in complex conditions. A genetic algorithm and tabu search hybrid algorithm (GATS) was designed to solve this problem. The algorithm used the global optimization capacity of genetic algorithm and the local hill climbing advantage of tabu search in the search process. The principium of the algorithm was introduced and a contrast experiment was carried out. The experiment and the analysis indicate the validity of the GATS to the optimization scheduling problem in complex conditions.

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Henselová, M., M. Regecová, and A. Sováková. "Isolation of chloroplasts in the Karwinskia species and determination of their photochemical activity under in vitro conditions." Plant, Soil and Environment 50, No. 4 (December 10, 2011): 149–56. http://dx.doi.org/10.17221/4075-pse.

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Reaction conditions for evaluation of the photochemical activity of isolated chloroplasts in the Hill reaction of Karwinskia humboldtiana (Roem & Schut) Zucc. and Karwinskia parvifolia Rose species were determined. Hill’s reaction activity was measured spectrophotometrically at 630 nm as the amount of DCPIP reduction by the chloroplast suspension at an irradiance of 400 µmol/m<sup>2</sup>/sPAR. A significant difference was observed between the activity of chloroplasts isolated at 2°C and 25°C amounting to 27% in Karwinskia humboldtiana and 18.5% in K. parvifolia. After 24 hours of storage of chloroplasts at a suspension of 2°C, a significant decrease of chloroplasts activity was noted in both species, e.g. 38% in Karwinskia humboldtiana and 45% in K. parvifolia. The photochemical activity of chloroplasts increased also with the length of irradiation of the reaction mixture and the content of chlorophyll (a + b) in chloroplast suspension. The activity of chloroplasts was found to be significantly higher in the species K. humboldtiana than in K. parvifolia and it proved higher in both when these were grown under field conditions rather than in a greenhouse.

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Wieczorek, Bartosz, Łukasz Warguła, and Dominik Rybarczyk. "Impact of a Hybrid Assisted Wheelchair Propulsion System on Motion Kinematics during Climbing up a Slope." Applied Sciences 10, no. 3 (February 4, 2020): 1025. http://dx.doi.org/10.3390/app10031025.

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Overcoming terrain obstacles presents a major problem for people with disabilities or with limited mobility who are dependent on wheelchairs. An engineering solution designed to facilitate the use of wheelchairs are assisted-propulsion systems. The objective of the research described in this article is to analyze the impact of the hybrid manual–electric wheelchair propulsion system on the kinematics of the anthropotechnical system when climbing hills. The tests were carried out on a wheelchair ramp with an incline of 4°, using a prototype wheelchair with a hybrid manual–electric propulsion system in accordance with the patent application P.427855. The test subjects were three people whose task was to propel the wheelchair in two assistance modes supporting manual propulsion. The first mode is hill-climbing assistance, while the second one is assistance with propulsion torque in the propulsive phase. During the tests, several kinematic parameters of the wheelchair were monitored. An in-depth analysis was performed for the amplitude of speed during a hill climb and the number of propulsive cycles performed on a hill. The tests performed showed that when propelling the wheelchair only using the hand rims, the subject needed an average of 13 ± 1 pushes on the uphill slope, and their speed amplitude was 1.8 km/h with an average speed of 1.73 km/h. The climbing assistance mode reduced the speed amplitude to 0.76 km/h. The torque-assisted mode in the propulsive phase reduced the number of cycles required to climb the hill from 13 to 6, while in the climbing assistance mode the number of cycles required to climb the hill was reduced from 12 to 10 cycles. The tests were carried out at various values of assistance and assistance amplification coefficient, and the most optimally selected parameters of this coefficient are presented in the results. The tests proved that electric propulsion assistance has a beneficial and significant impact on the kinematics of manual wheelchair propulsion when compared to a classic manual propulsion system when overcoming hills. In addition, assistance and assistance amplification coefficient were proved to be correlated with operating conditions and the user’s individual characteristics.

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Qi, Hui, Jing Guo, and Jie Yang. "The Ground Motion of Isosceles Triangular Hill in Right-Angle Plane Impacted by SH-Wave." Applied Mechanics and Materials 121-126 (October 2011): 2363–66. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.2363.

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The analytical solution to the problem of the scattering of SH-wave by isosceles triangular hill in right-angle plane is given by using the methods of complex function and multiple coordinate. Firstly, the solution region is divided into two domains, where domain I involves isosceles triangular hill and a semi-circular bottom, domain II involves a semi-circular hollow in right-angle plane. And a standing wave function is constructed which satisfies the zero-stress conditions at the triangular wedges. In domain II, the scattering wave functions which satisfy the stress free boundary conditions at the free surfaces for the right-angle plane are constructed. Secondly, based on the conditions of the displacement continuity and stress continuity at the “common border” in the domains, a series of infinite algebraic equations are given and solved by truncation. Finally, some examples for amplitude of displacement on the surface are given. Numerical results show that amplitude of displacement on the surface is influenced by isosceles triangular hill.

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Wang, Xue, Zhan Xing Yang, and Jing Lin Jiang. "Geological Features of Fuxin Gold Deposit." Advanced Materials Research 524-527 (May 2012): 130–33. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.130.

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Fuxin city is a part of low mountains and hills in Liaoning western, the plain and the hill occupy respectively 1/2. Metallogenic geological conditions of gold in Fuxin regions is superior, the types of mineral deposits is diverse, and it is dominated by Antique eon tough shear zone greenstone(mylonite) and altered rock type, volcanic type take second place, potential resource is larger, is an important production base of Liaoning province even the country. Therefore researching the geological characteristics of gold deposits in Fuxin region is of great significance.

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44

Soomro, Abdul Samad, Abdul Sattar Soomro, and Shabana Naz Mazari. "Impact of Plant Growth Regulators on Yield and Yield Components in Rice (Oryza sativa L.) Under Field Conditions." International Journal of Applied Sciences and Biotechnology 8, no. 3 (September 29, 2020): 318–22. http://dx.doi.org/10.3126/ijasbt.v8i3.31611.

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The exercise of using (PGRs), especially Gibberellic acid and in field of agriculture has become commercialized in some of the country including Pakistan. Number of different crops are being treated by farmers mostly vegetables; currently evaluated in rice crop through foliar application at different intervals to evaluate their efficiency at different doses. Results revealed that there was no significant difference in crop maturity compared with control. Plant height was variable among treated plots, highest plant height was recorded (121.2cm) in 2017-18 experiment in T-3 Gibberellic acid @ 12grams/acre while minimum (96.2cm) in 2016-17 in T-7 Control. Tillers/hill was increased, and maximum counted 18.5/hill in T-3 Gibberellic acid @ 10gms/acre whereas 11.9/hill was recorded in T-7 Control. Grain filling was obvious recorded with significance; counted 83 percent in T-5 Naphthalene acetic acid treated 100ml/acre whereas average minimum (71.3%) was recorded in T-7 Control. Not only plant development was modified by the treatments but yield was also increased average maximum (3228kgs/acre) with 19.61 percent was recorded in T-5 Naphthalene acetic acid @ 100ml/acre. Int. J. Appl. Sci. Biotechnol. Vol 8(3): 318-322

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Sandercock, Thomas G., and C. J. Heckman. "Force From Cat Soleus Muscle During Imposed Locomotor-Like Movements: Experimental Data Versus Hill-Type Model Predictions." Journal of Neurophysiology 77, no. 3 (March 1, 1997): 1538–52. http://dx.doi.org/10.1152/jn.1997.77.3.1538.

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Sandercock, Thomas G. and C. J. Heckman. Force from cat soleus muscle during imposed locomotor-like movements: experimental data versus Hill-type model predictions. J. Neurophysiol. 77: 1538–1552, 1997. Muscle is usually studied under nonphysiological conditions, such as tetanic stimulation or isovelocity movements, conditions selected to isolate specific properties or mechanisms in muscle. The purpose of this study was to measure the function of cat soleus muscle during physiological conditions, specifically a simulation of a single speed of slow walking, to determine whether the resulting force could be accurately represented by a Hill-type model. Because Hill-type models do not include history-dependent muscle properties or interactions among properties, the magnitudes of errors in predicted forces were expected to reveal whether these phenomena play important roles in the physiological conditions of this locomotor pattern. The natural locomotor length pattern during slow walking, and the action potential train for a low-threshold motor unit during slow walking, were obtained from the literature. The whole soleus muscle was synchronously stimulated with the locomotor pulse train while a muscle puller imposed the locomotor movement. The experimental results were similar to force measured via buckle transducer in freely walking animals. A Hill-type model was used to simulate the locomotor force. In a separate set of experiments, the parameters needed for a Hill-type model (force-velocity, length-tension, and stiffness of the series elastic element) were measured from the same muscle. Activation was determined by inverse computation of an isometric contraction with the use of the same locomotor stimulus pattern. During the stimulus train, the Hill-type model fit the locomotor data fairly well, with errors <10% of maximal tetanic tension. A substantial error occurred during the relaxation phase. The model overestimated force by ∼30% of maximal tetanic tension. A nonlinear series elastic element had little influence on the force predicted by a Hill model, yet dramatically altered the predicted muscle fiber lengths. Further experiments and modeling were performed to determine the source of errors in the Hill-type model. Isovelocity ramps were constructed to pass through a selected point in the locomotor movement with the same velocity and muscle length. The muscle was stimulated with the same locomotor pulse train. The largest errors again occurred during the relaxation phase following completion of the stimulus. Stretch during stimulation caused the Hill model to underestimate the relaxation force. Shortening movements during stimulation caused the Hill model to overestimate the relaxation force. These errors may be attributed to the effects of movement on crossbridge persistence, and/or the changing affinity of troponin for calcium between bound and unbound crossbridges, neither of which is well represented in a Hill model. Other sources of error are discussed. The model presented represents the limit of accuracy of a basic Hill-type model applied to cat soleus. The model had every advantage: the parameters were measured from the same muscle for which the locomotion was simulated and errors that could arise in the estimation of activation dynamics were avoided by inverse calculation. The accuracy might be improved by compensating for the apparent effects of velocity and length on activation. Further studies are required to determine to what degree these conclusions can be generalized to other movements and muscles.

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TRAGOONRUNG, S., P. M. HAYES, and B. L. JONES. "COMPARISON OF HILL AND ROW PLOTS FOR AGRONOMIC AND QUALITY TRAITS IN SPRING MALTING BARLEY (Hordeum vulgare L.)." Canadian Journal of Plant Science 70, no. 1 (January 1, 1990): 61–69. http://dx.doi.org/10.4141/cjps90-007.

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Provided they reliably predict row plot performance, hill plots should be useful for doubled haploid recurrent selection in malting barley (Hordeum vulgare L.). The primary objective of this research was to compare hill and row plot expression of agronomic and malting quality traits in an array of elite spring habit barley germplasm grown under irrigated conditions. A supporting objective was to identify an appropriate seeding rate for hill plot evaluation. Eight-replicate hill plots at four seeding rates (10, 20, 30, and 40 seeds per hill) were compared with adjacent four-replicate row plots in each of three environments. Genotype and genotype × environment interactions were significant for most agronomic traits in both plot types. Significant, linear genotype responses to hill plot seeding rates were observed for most agronomic traits. Seeding rate had no consistent effect on the expression of malting quality. The percentage of lines in common in the two plot types at 25 and 50% selection intensities was the most useful comparison statistic and indicated hill plot selection should be effective for most agronomic and malting quality traits. Although yield heritability estimates were consistently high in both hill and row plots, there was little relationship between trait expression in the two plot types. Differential tillering in response to hill plot competition is likely responsible. A seeding rate of 10 seeds per hill should be appropriate in preliminary screening for traits amenable to hill plot selection in irrigated spring habit malting barley.Key words: Hordeum vulgare L., malting quality, breeding methods, barley

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47

Conington, J., G. Simm, S. Bishop, and A. Waterhouse. "Environmental and genetic influences on hill lamb performance." Proceedings of the British Society of Animal Production (1972) 1993 (March 1993): 36. http://dx.doi.org/10.1017/s0308229600023655.

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Fat reserves are often perceived as essential to the hill ewe, so that they may be mobilised in adverse conditions to meet energy deficits. However, deer and some primitive breeds of sheep are remarkably lean animals which survive and thrive/reproduce in such conditions. The consequence of using genetically lean sheep in hill environments to meet the ultimate goal of reducing carcass fat is largely unknown. It is possible that the ewes' maternal ability, performance and welfare are in some way compromised. An SAC/IAPGR Hill Sheep Project was instigated: (1) to investigate if selection for differing fat levels under intensive concentrate feeding has any effect on progeny reared in extensive situations; (2) to determine the relationships between growth, carcass, reproduction, wool and survival traits, and to investigate which traits would be useful in an index of overall merit; and (3) to investigate if selection for improved carcass and growth characteristics affect maternal performance and survivability.

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Babu, Naresh, and Anamika Sharma. "Performance of papaya (Carica papaya L.) cultivars under Nagaland foot hill conditions." Journal of Applied Horticulture 04, no. 01 (June 15, 2002): 35–36. http://dx.doi.org/10.37855/jah.2002.v04i01.11.

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Kaur, Manmeet, Sanjay Chadha, Nitish Kumar, Nidhi Sehgal, and Sangeeta Kanwar. "Genetic evaluation of cabbage hybrids under mid hill conditions of Himachal Pradesh." Journal of Hill Agriculture 9, no. 1 (2018): 35. http://dx.doi.org/10.5958/2230-7338.2018.00006.x.

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Ohba, R., T. Hara, S. Nakamura, Y. Ohya, and T. Uchida. "Gas diffusion over an isolated hill under neutral, stable and unstable conditions." Atmospheric Environment 36, no. 36-37 (December 2002): 5697–707. http://dx.doi.org/10.1016/s1352-2310(02)00642-8.

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Journal articles on the topic 'Hill, conditions de'

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