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Effect of particle stress tensor in simulations of dense gas-particle flows in fluidized beds

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Particuology 2018年第3期16卷 31-43页

作者： Mohammad Reza Haghgoo Donald j. Bergstrom raymond j. Spiteri Department of Mechanical Engineering University of Saskatchewan Saskatoon SK SFN 5A9 Canada Department of Computer Science University of Saskatchewan Saskatoon. SK S7N 5C9 Canada

A two-fluid model based on the kinetic theory of granular flow for the rapid-flow regime and the Coulomb friction law for the quasi-static regime is applied to predict the hydrodynamics of dense gas-particle flow in a three-dimensional fluidized bed. Two different models for the particle stress tensor that use different constitutive equations in the elastic-inertial regime are examined to assess their ability to predict bed dynamics. To understand how particle stress models affect structural features of the flow, a quantitative analysis is performed on some important aspects of the mechanics of bubbling beds that have received relatively little attention in the literature. Accordingly, different flow regimes are identified in the context of fluidized beds through the dimensionless inertial number, and the main characteristics of each regime are discussed. In addition, how the particle stress tensor manifests itself in the bubble characteristics, natural frequency of the bed, and particle Reynolds stress are investigated, all of which help to better understand the complex dynamics of the fluidized bed. The numerical results are validated against pub- lished experimental data and demonstrate the significant role of the stress tensor in the elastic-inertial regime.

关键词： Two-fluid model Inertial number Fluidized bed Flow regime Particle Reynolds stress MFIX

Optimal decentralized control of large scale systems

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Control Theory and Technology 2016年第4期14卷 287-313页

作者： Xiao Qi SHI Daniel E. DAVISON raymond KWONG Edward j. DAVISON Systems Control Group Department of Electrical and Computer Engineering University of Toronto Ontario Canada MSS 3G4 Department of Electrical and Computer Engineering University of Waterloo Ontario Canada N2L 3G1

This paper presents a new optimized decentralized controller design method for solving the tracking and disturbance rej.ction problems for large-scale linear time-invariant systems, using only low-order decentralized controllers. To illustrate the type of results which can be obtained using the new optimized decentralized control design method, the control of a large flexible space structure is studied and compared with the standard centralized LQR-observer controller. The order of the resultant decentralized controller is much smaller than that of the standard centralized LQR-observer controller. The proposed controller also has certain fail-safe properties and, in addition, it can be five orders of magnitude more robust than the standard LQR-observer controller based on their real stability radii. The new decentralized controller design method is applied to a large flexible space structure system with 5 inputs and 5 outputs and of order 24.

关键词： Decentralized control multivariable control PID control robustness optimization large-scale systems flexiblestructures

Plant-based nutrition for healthcare professionals： implementing diet as aprimary modality in the prevention and treatment of chronic disease

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j.urnal of Geriatric Cardiology 2017年第5期14卷 355-368页

作者： j.lieanna Hever raymond j.Cronise To Your Health Fitness and Nutrition Beverly Hills CA USA Thermogenex Huntsville AL USA

Cardiovascular disease remains the world＇s leading cause of death. Yet, we have known for decades that the vast maj.rity of athero-sclerosis and its subsequent morbidity and mortality are influenced predominantly by diet. This paper will describe a health-promoting wholefood, plant-based diet; delineate macro- and micro-nulxition, emphasizing specific geriatric concerns; and offer guidance to physicians andother healthcare practitioners to support patients in successfully utilizing nutrition to improve their health.

关键词： Aging Health span Plant-based nutrition Preventive medicine Vegetarian

Binding of Cry δ-endotoxins to brush border membrane vesicles of Helicoverpa armigera and Helicoverpa punctigera （Lepidoptera： Noctuidae）

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Insect Science 2005年第4期12卷 231-240页

作者： CHUNYAN LIAO LIZ BROOKS STEPHEN C. TROWELL raymond j. AKHURST CSIRO Entomology Australian National University ACT Australia Division of Biochemistry and Molecular Biology Australian National University ACT Australia

The relatively low susceptibility ofHelicoverpa armigera to CrylAc, its history of resistance to chemical insecticides and the seasonal decline in expression of CrylAc in transgenic cotton necessitated the development of cotton expressing two insecticidal proteins to provide sustainable control of this multinational pest. To manage the resistance issue, it was essential that the second insecticidal protein have a significantly different mode of action to CrylAc. A common feature of resistance to CrylA proteins in several species as well as H. armigera has been a change in the binding site. A study of binding sites for some Cry proteins in the brush border membrane vesicles （BBMV） ofH. armigera and Helicoverpa punctigera was undertaken. The binding affinity for CrylAc was higher than for CrylAb, matching their relative toxicities, and CrylAc and CrylAb were found to share at least one binding site in both I-1. armigera and I-1. punctigera. However Cry2Aa did not compete with CrylAc for binding and so could be used in transgenic cotton in combination with CrylAc to control H. armigera and manage resistance. Variation in the susceptibilities of three different H. armigera strains to CrylAc correlated with the parameter Bmax/Kcom.

关键词： Helicoverpa armigera Helicoverpa punctigera Bacillus thuringiensis δ-endotoxin brush border membrane vesicles ligand binding

Allometric models for estimating aboveground biomass in the tropical woodlands of Ghana, West Africa

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Forest Ecosystems 2020年第3期7卷 539-561页

作者： raymond Aabeyir Stephen Adu-Bredu Wilson Agyei Agyare Michael j.C.Weir Department of Environment and Resource Studies UDS-Wa CampusWaGhana WASCAL Graduate Research Programme on Climate Change and Land Use KNUSTKumasiGhana Biodiversity Conservation and Ecosystem Division CSIR-Forestry Research Institute of GhanaKumasiGhana Department of Agricultural and Biosystems Engineering KNUSTKumasiGhana Department of Natural Resources Faculty of Geoinformation Science and Earth Observation(ITC)University of TwenteEnschedethe Netherlands

Background: Modelling aboveground biomass(AGB) in forest and woodland ecosystems is critical for accurate estimation of carbon stocks. However, scarcity of allometric models for predicting AGB remains an issue that has not been adequately addressed in Africa. In particular, locally developed models for estimating AGB in the tropical woodlands of Ghana have received little attention. In the absence of locally developed allometric models, Ghana will continue to use Tier 1 biomass data through the application of pantropic models. Without local allometric models it is not certain how Ghana would achieve Tier 2 and 3 levels under the United Nations programme for reducing emissions from deforestation and forest degradation. The obj.ctive of this study is to develop a mixedspecies allometric model for use in estimating AGB for the tropical woodlands in Ghana. Destructive sampling was carried out on 745 trees(as part of charcoal production) for the development of allometric equations. Diameter at breast height(dbh, i.e. 1.3 m above ground level), total tree height(H) and wood density(ρ) were used as predictors for the models. Seven models were compared and the best model selected based on model efficiency,bias(%) and corrected Akaike Information Criterion. The best model was validated by comparing its results with those of the pantropic model developed by Chave et al.(Glob Chang Biol 20:3177–3190, 2014) using equivalence test and conventional paired ***: The results revealed that the best model for estimating AGB in the tropical woodlands is AGB =0.0580ρ((dbh)2 H)0.999. The equivalence test showed that this model and the pantropic model developed by Chave et al.(Glob Chang Biol 20:3177–3190, 2014) were equivalent within ±10% of their mean predictions(p-values <0.0001 for one-tailed t-tests for both lower and upper bounds at 5% significant level), while the paired t-test revealed that the mean(181.44 ± 18.25 kg) of the model predictions of the best model of this s

关键词： Charcoal Diameter at breast height Tree height Wood density Savannah woodland

Pesticide exposures and respiratory health in general populations

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j.urnal of Environmental Sciences 2017年第1期29卷 361-370页

作者： Ming Ye j.remy beach j.nathan W.Martin Ambikaipakan Senthilselvan School of Public Health University of AlbertaEdmontonAlberta T6G 1C9Canada Division of Preventive Medicine Department of MedicineUniversity of AlbertaEdmontonAlberta T6G 2T4Canada Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and PathologyUniversity of AlbertaEdmontonAlberta T6G 2GSCanada

Human exposures to pesticides can occur in the workplace,in the household and through the ambient *** several articles have reviewed the impact of pesticide exposures on human respiratory health in occupational settings,to the best of our knowledge,this article is the first one to review published studies on the association between pesticide exposures and human respiratory health in the general *** this article,we critically reviewed evidences up to date studying the associations between non-occupational pesticide exposures and respiratory health in general *** article also highlighted questions arising from these studies,including our recent analyses using the data from the Canadian Health Measures Survey（CHMS）,for future *** found few studies have addressed the impact of environmental pesticide exposures on respiratory health,especially on lung function,in general *** the studies using the data from CHMS Cycle 1,exposures to OP insecticides,pyrethroid insecticides,and the organochlorine pesticide DDT were associated with impaired lung function in the Canadian general population,but no significant associations were observed for the herbicide 2,*** research should focus on the potential age-specific and pesticide-specific effect on respiratory health in the general population,and repeated longitudinal study design is critical for assessing the temporal variations in pesticide *** findings from current studies of non-occupational pesticide exposures and their health impact in general population will help to improve the role of regulatory policies in mitigating pesticide-related public health problems,and thereafter providing greater benefit to the general population.

关键词： Canadian Health Measures Survey Environmental General population Pesticides Respiratory health

Endogenous bioelectric fields: a putative regulator of wound repair and regeneration in the central nervous system

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Neural Regeneration Research 2016年第6期11卷 861-864页

作者： Matthew L.Baer raymond j.Colello Department of Anatomy & Neurobiology Virginia Commonwealth University

Studies on a variety of highly regenerative tissues, including the central nervous system（CNS） in non-mammalian vertebrates, have consistently demonstrated that tissue damage induces the formation of an ionic current at the site of inj.ry. These inj.ry currents generate electric fields（EF） that are 100-fold increased in intensity over that measured for uninj.red tissue. In vitro and in vivo experiments have convincingly demonstrated that these electric fields（by their orientation, intensity and duration） can drive the migration, proliferation and differentiation of a host of cell types. These cellular behaviors are all necessary to facilitate regeneration as blocking these EFs at the site of inj.ry inhibits tissue repair while enhancing their intensity promotes repair. Consequently, inj.ry-induced currents, and the EFs they produce, represent a potent and crucial signal to drive tissue regeneration and repair. In this review, we will discuss how inj.ry currents are generated, how cells detect these currents and what cellular responses they can induce. Additionally, we will describe the growing evidence suggesting that EFs play a key role in regulating the cellular response to inj.ry and may be a therapeutic target for inducing regeneration in the mammalian CNS.

关键词： repair regeneration currents inducing consistently regulating migration potent wound facilitate

Prevalence of Careers in Psychology Courses at American Universities

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考试与评价（大学英语四级考试版） 2009年第11期 37-38页

作者： raymond j. Green

大学不仅要开设普通的心理学课程，而且还要在心理学课程里加入有关将来职业规划的课题，这是社会经济结构发展要求大学成为职业训练和准备基地的必然结果。美国的一些研究表明，开设此类课题的意义重大，有助于大学生储备与将来职业相... 详细信息

大学不仅要开设普通的心理学课程，而且还要在心理学课程里加入有关将来职业规划的课题，这是社会经济结构发展要求大学成为职业训练和准备基地的必然结果。美国的一些研究表明，开设此类课题的意义重大，有助于大学生储备与将来职业相关的知识，有助于大学生在毕业之后找到较好的工作……

关键词：高校英语课外阅读阅读材料

Unsupervised ore/waste classification on open-cut mine faces using close-range hyperspectral data

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Geoscience Frontiers 2023年第4期14卷 89-99页

作者： Lloyd Windrim Arman Melkumyan Richard j.Murphy Anna Chlingaryan raymond Leung Rio Tinto Centre for Mine Automation Australian Centre for Field RoboticsThe University of SydneySydney 2006Australia

The remote mapping of minerals and discrimination of ore and waste on surfaces are important tasks for geological applications such as those in *** tasks have become possible using ground-based,close-range hyperspectral sensors which can remotely measure the reflectance properties of the environ-ment with high spatial and spectral ***,autonomous mapping of mineral spectra mea-sured on an open-cut mine face remains a challenging problem due to the subtleness of differences in spectral absorption features between mineral and rock classes as well as variability in the illumination of the *** additional layer of difficulty arises when there is no annotated data available to train a supervised learning algorithm.A pipeline for unsupervised mapping of spectra on a mine face is pro-posed which draws from several recent advances in the hyperspectral machine learning *** proposed pipeline brings together unsupervised and self-supervised algorithms in a unified system to map minerals on a mine face without the need for human-annotated training *** pipeline is eval-uated with a hyperspectral image dataset of an open-cut mine face comprising mineral ore martite and non-mineralised *** combined system is shown to produce a superior map to its constituent algo-rithms,and the consistency of its mapping capability is demonstrated using data acquired at two differ-ent times of day.

关键词： Hyperspectral imaging Mineral mapping Open-cut mine face Machine learning Convolutional neural networks Illumination invariance