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Hepatobiliary Surgery and Nutrition 2021年第5期10卷 702-704页

作者： rick J.Jansen Department of Public Health GenomicsPhenomicsand Bioinformatics ProgramCenter for Immunization Research and Education(CIRE)Center for Diagnostic and Therapeutic Strategies in Pancreatic CancerNorth Dakota State UniversityFargoNDUSA

In their manuscript,“Whole-Grain Intake and Pancreatic Cancer Risk-The Danish,Diet,Cancer and Health Cohort”,Schacht et al.(1)report that total whole-grain product(per 50 g/d serving)intake was significantly associated with lower incidence of pancreatic cancer(HR:0.93;95%CI:0.86,1.00).A sex-specific analysis revealed that this association only held among ***,neither total whole-grain(per 16-g serving)or specific individual whole-grain products and cereals were significantly associated with lower pancreatic cancer *** this commentary,I will describe some of the assumptions and biases associated with assessing dietary intake and attempting to find associations with disease.

关键词： intake cancer

Invasive weed disrupts facilitation of nutrient uptake in grass-clover assemblage

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Soil Ecology Letters 2024年第1期6卷 89-96页

作者： Wei Zhang rick Muir Nicholas Dickinson Faculty of Agriculture and Life Sciences Lincoln UniversityLincoln 7647New Zealand

Nutrient constraints in low-fertility soil were modified by different species ***-clover assemblages benefited both species in terms of nutrient *** of competition and facilitation is *** invasive weed removed essential nutrients from the grazing *** investigate the interplay of competition and facilitation between plants in low-fertility pasture grasslands of New Zealand,we compared nutrient uptake and acquisition of key nutrients of three species from different func-tional *** of Pilosella officinarum(mouse-eared hawk-weed,an invasive weed),Trifolium repens(white clover,a nitrogen fixer)and Dactylis glomerata(cocksfoot,a pasture grass)were planted into a soil with low-to-deficient concentrations of key *** yields were achieved by the grass growing alone but,when the clover and grass had grown together,there were complementary benefits in terms of procurement of a wide range of nutrients from soil despite lower root *** inva-sive weed negated these benefits,and soil nutrients were exploited less efficiently when Pilosella had grown alone or in a mixture with the other *** from the weed removed the benefits of grass-legume *** findings are interpreted to suggest that requirements for legumes to be the main source of nitrogen in pasture grasslands may be compromised unless competitive weeds are controlled to avoid disrupted procurement of key *** is likely these constraints to nutrient procurement would similarly impact conservation grasslands.

关键词： soil ferility facilitation species coexistence weed invasion legumes

Segmentation and classification of high resolution imagery for mapping individual species in a closed canopy,deciduous forest

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Science China(Technological Sciences) 2006年第z1期49卷 128-139页

作者： Timothy A.Warner James B.McGraw rick Landenberger Department of Geology and Geography West Virginia UniversityMorgantown WV 26506-6300USA Biology Department West Virginia UniversityMorgantown WV 26506USA

In this paper we investigate the use of a shadow-based delineation program for identifying segments in imagery of a closed canopy, deciduous forest, in West Virginia, USA, as a way to reduce the noise associated with per-pixel classification in forested environments. Shadows typically cluster along the boundaries of trees and therefore can be used to provide a network of nodes for the delineation of segments. A minimum cost path algorithm, where cost is defined as the cumulative sum of brightness values traversed along the connecting route, was used to connect shadow clumps. To test this approach, a series of classifications was undertaken using a multispectral digital aerial image of a six hectare test site and a minimum cost path segmentation. Three species were mapped: oaks, red maple and yellow poplar. The accuracy of an aspatial maximum likelihood classification (termed PERPIXEL classification) was 68.5%, compared to 74.0% for classification using the mean vector of the segments identified with the minimum cost path algorithm (MEAN_SEG), and 78% when the most common class present in the segment is assigned to the entire segment (POSTCLASS_SEG). By comparison, multispectral classification of the multispectral data using the field-mapped polygons of individual trees as segments, produced an accuracy of 82.3% when the mean vector of the polygon was used for classification (MEAN_TREE), and 85.7% when the most common class was assigned to the entire polygon (POSTCLASS_TREE). A moving window-based post-classification majority filter (POSTCLASS_MAJ5BY5) produced an intermediate accuracy value, 73.8%. The minimum cost path segmentation algorithm was found to correctly delineate approximately 28% of the trees. The remaining trees were either segmented, aggregated, or a combination of both segmented and aggregated. Varying the threshold that was used to discriminate shadows appeared to have little effect on the number of correctly delineated trees, or on the overall accu

关键词： remote sensing, digital forestry, image classification, segmentation.

Nanobubble generation and its applications in froth flotation(part IV):mechanical cells and specially designed column flotation of coal

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Mining Science and Technology 2010年第5期20卷 641-671页

作者： FAN Maoming TAO Danie HONAKER rick LUO Zhenfu Department of Mining Engineering University of Kentucky Lexington KY 40506 USA CPT Eriez Manufacturing Co Erie PA 16514 USA School of Chemical Engineering and Technology China University of Mining & Technology Xuzhou 221116 China

Coal is the world's most abundant fossil *** froth flotation is a widely used cleaning process to separate coal from mineral *** of coarse coal particles,ultrafine coal particles and oxidized coal particles is well known to be difficult and *** this paper,the nanobubbles' effects on the flotation of the varying particle size,particle density and floatability coal samples were evaluated using a bank of pilot scale flotation cells,a laboratory scale and a pilot scale specially designed flotation *** parameters evaluated during this study include the flow rate ratio between the nanobubble generator and the conventional size bubble generator,the superficial air velocity,collector dosage,frother concentration,flotation feed rate,feed solids concentration,feed particle size,and the superficial wash water flow rate,*** results show that the use of nanobubbles in a bank of mechanical cells flotation and column flotation increased the flotation recovery by 8%～27% at a given product *** increased the flotation rate constants of 600～355,355～180,180～75,and 75～0 microns size coal particles by 98.0%,98.4%,50.0% and 41.6%,*** separation selectivity index was increased by up to 34%,depending on the flotation feed characteristics and the flotation conditions.

关键词： coal froth flotation cavitation nanobubble flotation kinetics

Key Techniques in Real Time Digital Simulation for Closed-loop Testing of HVDC Systems

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CSEE Journal of Power and Energy Systems 2017年第2期3卷 125-130页

作者： Yi Zhang Hui Ding rick Kuffel RTDS Technologies Inc. WinnipegManitobaCanada

This paper introduces several key techniques in realtime digital simulation for closed-loop testing of high voltage direct current(HVDC)systems,including line commutated converter(LCC)HVDC valve group models,modular multilevel converter(MMC)HVDC models,phase domain frequency dependent transmission line models,and switchable filter *** issues such as background,algorithms,implementations,applications,and validation of these models are *** techniques represent the most advanced technology in modelling HVDC systems on a real time *** models have been implemented on the RTDS Simulator,a comprehensive real time power system digital simulation tool.

关键词： HVDC real time simulation

Nanobubble generation and its application in froth flotation (part I): nanobubble generation and its effects on properties of microbubble and millimeter scale bubble solutions

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Mining Science and Technology 2010年第1期20卷 1-19页

作者： FAN Maoming TAO Daniel HONAKER rick LUO Zhenfu Department of Mining Engineering University of Kentucky Lexington KY40506 USA CPT Eriez Manufacturing Co. Erie PA 16514 USA School of Chemical Engineering and Technology China University of Mining & Technology Xuzhou 221116 China

A special nanobubble generation system has been developed for evaluating the effect of nanobubble on froth flotation. In this study, an eight-factor five-level Central Composite Experimental Design was conducted for investigating eight important parameters governing the median size and the volume of nanobubbles. These process parameters included surfactant concentration, dissolved oxygen (O2) content, dissolved carbon dioxide gas (CO2) content, pressure drop in cavitation tube nozzle, <50 nm hydrophobic particle concentration, <50 nm hydrophilic particle concentration, slurry temperature and the time interval after nanobubble generation. The properties, stability and uniformity of nanobubbles were investigated. The study of the produced nanobubble’s effects on the characteristics of microbubble solutions and millimeter scale bubble solutions was performed in a 50.8 mm column.

关键词： nanobubble cavitation Zeta potential microbubble froth flotation

Determination of velocity correction factors for real-time air velocity monitoring in underground mines

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International Journal of Coal Science & Technology 2017年第4期4卷 322-332页

作者： Lihong Zhou Liming Yuan rick Thomas Anthony Iannacchione Pittsburgh Mining Research Division Office of Mine Safetyand Health Research National Institute for OccupationalSafety and Health PO Box 18070 626 Cochrans Mill RoadPittsburgh PA 15236 USA University of Pittsburgh Pittsburgh PA USA

When there are installations of air velocity sensors in the mining industry for real-time airflow monitoring, a problem exists with how the monitored air velocity at a fixed location corresponds to the average air velocity, which is used to determine the volume flow rate of air in an entry with the cross-sectional area. Correction factors have been practically employed to convert a measured centerline air velocity to the average air velocity. However, studies on the recommended correction factors of the sensor-measured air velocity to the average air velocity at cross sections are still lacking. A comprehensive airflow measurement was made at the Safety Research Coal Mine, Bruceton, PA, using three measuring methods including single-point reading, moving traverse, and fixed-point traverse. The air velocity distribution at each measuring station was analyzed using an air velocity contour map generated with Surfer~. The correction factors at each measuring station for both the centerline and the sensor location were calculated and are discussed.

关键词： Underground mine Airflow measurement - Correction factor

Ultraviolet reflection enhances the risk of predation in a vertebrate

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Current Zoology 2013年第2期59卷 151-159页

作者： Ricarda MODARRESSIE IngolfE rick Theo C. M. BAKKER Institute for Evolutionary Biology and Ecology University of Bonn An der Immenburg 1 D-53121 Bonn Germany

Many animals are sensitive to ultraviolet light and also possess UV-reflective regions on their body surface. Individu- als reflecting UV have been shown to be preferred during social interactions such as mate choice or shoaling decisions. However, whether those body UV-reflections enhance also the conspicuousness to UV-sensitive predators and thereforeentail costs for its bearer is less well documented. Two size-matched three-spined sticklebacks Gasterosteus aculeatus, one enclosed in a UV-transmitting （UV＋） and another in a UV-blocking （UV-） chamber, were simultaneously presented to individual brown trout Salmo trutta. ＂yearlings＂. Brown trout of this age are sensitive to the UV part of the electromagnetic spectnun and are natural predators of three-spined sticklebacks. The stickleback that was attacked first as well as the subsequent number of attacks was recorded. Sticklebacks enclosed in the UV-transmitting chamber were attacked first significantly more often compared to stickle- backs enclosed in the UV-blocking chamber. Control experiments using neutral density filters revealed that this was more likely due to LrV having an influence on hue perception rather than brighmess discrimination. The difference in attack probability cor- responded to the difference in chromatic contrasts between sticklebacks and the experimental background calculated for both the UV＋ and UV- conditions in a physiological model of trout colour vision. UV reflections seem to be costly by enhancing the risk of predation due to an increased conspicuousness of prey. This is the first study in a vertebrate, to our knowledge, demonstrating direct predation risk due to UV wavelengths [Current Zoology 59 （2）： 151-159, 2013].

关键词： UV vision Brown trout Salmo trutta Ultraviolet reflection Three-spined stickleback Gasterosteus aculeatus Pre-dation risk

Simplified thermal and hygric building models： A literature review

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Frontiers of Architectural Research 2012年第4期1卷 318-325页

作者： rick Kramer Jos van Schijndel Henk Schellen Deportment of the Built Environment Eindhoven University of Technology Eindhoven 5612 AZ The Netherlonds

This paper provides a systematic literature review on simplified building modelso Questions are answered like： What kind of modelling approaches are applied？ What are their （dis）advantages？ What are important modelling aspects？ The review showed that simplified building models can be classified into neural network models （black box）, linear parametric models （black box or grey box） and lumped capacitance models （white box）. Research has mainly dealt with network topology, but more research is needed on the influence of input parameters. The review showed that particularly the modelling of the influence of sun irradiation and thermal capacitance is not performed consistently amongst researchers. Furthermore, a model with physical meaning, dealing with both temperature and relative humidity, is still lacking. Inverse modelling has been widely applied to determine models parameters. Different optimization algorithms have been used, but mainly the conventional Gaus-Newton and the newer genetic algorithms. However, the combination of algorithms to combine their strengths has not been researched. Despite all the attention for state of the art building performance simulation tools, simplified building models should not be forgotten since they have many useful applications. Further research is needed to develop a simplified hygric and thermal building model with physical meaning.

关键词： Literature review Building performancesimulation Simplified buildingmodels Inverse modelling Climate change

Parametric study of electrostatic separation of South African fine coal

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Mining Science and Technology 2010年第4期20卷 535-541页

作者： BADA Samson TAO Daniel HONAKER rick FALCON Lionel FALCON Rosemary School of Chemical and Metallurgical Engineering Faculty of Engineering and the Built Environment University of the Witwatersrand Department of Mining Engineering University of Kentucky

The fact that water requirements are a major problem for present and future developments in material beneficiation, and the construction of a new power plant in South Africa, forms the basis for the utilization of a Rotary Triboelectrostatic Separator (RTS) for beneficiation of South African pulverized coal. The cleaning potential of Majuba and Koorfontein coal was first evaluated using kinetic froth flotation tests on the -177 μm coal fraction. The RTS tests were conducted under varied process parameters. Parameters such as applied separating voltage, air injection velocity, particle feed rate and splitter position were investigated. Two stage separation results show that the RTS reduced Majuba coal initially containing about 30% ash to a clean product of 14.30%, or 19.46%, ash at a combustible recovery of 15.10%, or 53.02%, respectively. Similar separation performance was also achieved with the Koorfontein coal. The mineral and organic compositions in the feed, after single stage and after the second stage separations were characterized using X-ray diffraction analysis. The results show a better separation for the second stage coal products.

关键词： coal cleaning particle charging RTS technique separation stage