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Estimating underground mine ventilation friction factors from low density 3D data acquired by a moving LiDAR

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International Journal of mining science and Technology 2018年第4期28卷 650-655页

作者： Curtis Watson joshua marshall mining systems Laboratory The Robert M.Buchan Department of Mining Queen's University

Ventilation system analysis for underground mines has remained mostly unchanged since the Atkinson method was made popular by mc Elroy in 1935. Data available to ventilation technicians and engineers is typically limited to the quantity of air moving through any given heading. Because computer-aided modelling, simulation, and ventilation system design tools have improved, it is now important to ensure that developed models have the most accurate information possible. This paper presents a new technique for estimating underground drift friction factors that works by processing 3 D point cloud data obtained by using a mobile Li DAR. Presented are field results that compare the proposed approach with previously published algorithms, as well as with manually acquired measurements.

关键词： mine ventilation mine design mobile mapping Roughness estimation Friction factors LiDAR3D point clouds

molecular approaches to study the insect gut symbiotic microbiota at the ＇omics＇ age

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Insect science 2010年第3期17卷 199-219页

作者： Weibing shi Ryan syrenne Jian-Zhong sun joshua s. Yuan Department of Plant Pathology and microbiology Institute for Plant Genomics and Biotechnology Texas A&M University TexasUSA Biofuels Institute School of the Environment Jiangsu University Zhenjiang Jiangsu Province China Advanced Research Institute for sustainable Energy (ARIsE) Texas A&M University Texas USA

Insect gut symbiotic microbiota play essential roles in the growth, development, pathogenesis and environmental adaptation of host insects. The molecular and systems level analysis of insect gut symbiotic microbial community will allow us to discover novel biocatalysts for biomass deconstruction and to develop innovative strategies for pest management. We hereby review the various molecular biology techniques as applied to insect gut symbiont analysis. This review aims to serve as an informative resource for experimental design and research strategy development in the field. We first discuss various strategies for sample preparation and their pros and cons. The traditional molecular techniques like DGGE, RFLP and FIsH are covered with respect to how they are applied to study the composition, diversity and dynamics of insect gut symbiotic microbiota. We then focus on the various ＇ omics＇ techniques. The metagenome analysis together with the recent advancements in next-generation sequencing will provide enormous sequencing information, allowing in-depth microbial diversity analysis and modeling of pathways for biological processes such as biomass degradation. The metagenome sequencing will also enable the study of system dynamics and gene expression with metatranscriptome and metaproteome methods. The integration of different ＇omics＇ level data will allow us to understand how insect gut works as a system to carry out its functions. The molecular and systems-level understanding will also guide the reverse design of next-generation biorefinery.

关键词： DGGE insect gut metagenomics metaproteomics symbiotic microbiota systems biology

The legal sustainability of energy substitution in Nigeria’s electric power sector:renewable energy as alternative

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Protection and Control of modern Power systems 2020年第1期5卷 378-389页

作者： Olusola joshua Olujobi Legal Practitioner and Lecturer Business Management Department Covenant University Ota Ogun State Nigeria

Non-renewable fuel sources have been the predominant energy sources and a significant source of foreign exchange income for Nigeria,while at the same time there is a severe problem of electricity inconsistency and persistent power blackouts in *** research aims to end the concern for deficient energy use,and to encourage energy efficiency and *** has not maximized the advantages of renewable energy after the denationalisation of its electricity industry despite the current transformation in the power industry and the rising demand for renewable energy *** research adopts a doctrinal legal approach with a library-based legal research technique with a comparative legal *** reveals that the absence of a comprehensible legal regime with encouragement for the use of renewable energy is the fundamental element causing the slow utilization of renewable energy as a substitute source of energy in *** is suggested that,among other reforms,there is a need for a comprehensible legal regime on renewable energy and the encouragement of strict implementation of energy regulatory strategies and policies with incentives for the application of renewable energy sources in Nigeria.

关键词： Non-renewable energy sustainability Renewable energy Fossil fuel Nigeria

Associations with pancreatic exocrine insufficiency:An United Kingdom single-centre study

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World Journal of Clinical Cases 2021年第31期9卷 9469-9480页

作者： Benjamin m shandro joshua Chen Jennifer Ritehnia Andrew Poullis Department of Gastroenterology St George's University Hospitals NHS Foundation TrustLondon SW170QTUnited Kingdom

BACKGROUND Pancreatic exocrine insufficiency(PEI)is said to be associated with numerous conditions both within and outside the gastrointestinal(GI)*** majority of research has been concerned with conditions that reduce the volume of functioning pancreatic tissue or prevent adequate drainage to the small bowel,such as chronic pancreatitis,cystic fibrosis,pancreatic cancer and pancreatic ***,the evidence base supporting an association with extrapancreatic conditions,such as coeliac disease,diabetes mellitus and congestive cardiac failure,is *** To strengthen the evidence base by studying all previously reported associations with PEI in a large cohort of *** A single-centre retrospective study was *** gastroenterology outpatients tested for PEI with faecal elastase-1(FE1)were identified and information retrieved from the electronic patient *** was defined as FE1me replacement therapy were *** imputation was used to handle missing *** logistic regression was used to study which presenting symptoms predicted *** logistic regression was used to explore the relationship between all previously reported associations and *** Of 1027 patients were included.182 patients(17.7%)were diagnosed with ***[odds ratios(OR):2.51,95%confidence intervals(CI):1.58-3.98]and weight loss(OR:1.49,95%CI:1.08-2.06)were the only presenting symptoms that predicted *** pancreatitis(OR:7.98,95%CI:3.95-16.15),pancreatic cancer(OR:6.58,95%CI:1.67-25.98),upper GI surgery(OR:2.62,95%CI:1.32-5.19),type 2 diabetes(OR:1.84,95%CI:1.18-2.87),proton pump inhibitor therapy(OR:1.87,95%CI:1.25-2.80)and Asian ethnicity(OR:2.11,95%CI:1.30-3.42)were significantly associated with PEI in the multivariable *** of the other historically reported associations with PEI were significant after adjustment for the other variable

关键词： Exocrine pancreatic insufficiency Chronic pancreatitis Pancreatic elastase steatorrhoea Proton pump inhibitors

Influence of climate fluctuations on Pinus palustris growth and drought resilience

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Forest Ecosystems 2023年第6期10卷 681-689页

作者： Joao Campoa joshua Puhlick CENsE–Center for Environmental and sustainability Research CHANGE-Global Change and Sustainability InstituteDepartment of Environmental Sciences and EngineeringNOVA School of Science and TechnologyNOVA University LisbonCampus de Caparica2829-516 CaparicaPortugal The Jones Center at Ichauway 3988 Jones Center Drive39870NewtonGAUSA

The longleaf pine(Pinus palustris mill.)ecosystem is an endangered ecosystem in the southeastern UsA,and efforts to restore the species are ***,in recent decades,the region has experienced drastic fluctuations between wet and dry growing season conditions from year to year,and it is not fully understood how these fluctuations have influenced the growth of *** address this topic,we cored *** trees in woodlands of southwest Georgia and used dendrochronology techniques to determine how climate fluctuations have influenced the growth and drought resilience of *** also cored slash pine(Pinus elliottii Engelm.)trees in the same woodlands to compare growth between *** *** growth was less impacted by adverse climate conditions compared to ***,the strength of correlations between *** growth and temperature,precipitation,and Palmer Drought severity Index(PDsI)changed over *** recent decades,climate conditions during the growing season became more influential on *** growth than the previous year's *** is concerning given that drought severity during the growing season has been *** results also indicate that *** was less resilient to droughts during the 2000s and 2010s than to those of the *** this new climate paradigm,our results suggest that *** might be more susceptible to growth reductions and less resistant to droughts than once *** work highlights the importance of understanding the impact of novel climate conditions on *** and has implications for restoration efforts,such as using silvicultural treatments that reduce tree vulnerability to drought(e.g.,thinning)and promote other climate-adapted species in mixture with ***.

关键词： Longleaf pine slash pine Pinus elliottii Climate change Dendrochronology Dendroclimatology Forest disturbances

Fundamental behaviours of production traffic in underground mine haulage ramps

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International Journal of mining science and Technology 2015年第1期25卷 7-14页

作者： Haviland David marshall joshua Golder Associates Ltd. The Robert m. Buchan Department of mining Queen’s University

Ramps(or declines) are often used in underground mines to transport ore, waste, materials, and personnel. This paper studies mine ramp productivity and presents results from a set of computer simulations designed to model the fundamental behaviours of ramp haulage systems. simulations show that, under fundamental assumptions without random disturbances, the haulage system always converges to a periodic behaviour in the steady state, but that productivities vary between equilibria. simulations also demonstrate how productivity per vehicle does not necessarily decrease as more vehicles are added and,for example, in the five-vehicle case, how a 3.1% improvement can be achieved over the use of four vehicles. The result reveals the inefficiency of commonly-used lockout-style vehicle coordination strategies,and suggests a possible avenue for improving the productivity of haulage ramps by controlling the system to achieve more productive behaviours.

关键词： Underground miningFleet managementDiscrete-time simulationVehicle dispatching

seven Things We Think We Know about Auxin Transport

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molecular Plant 2011年第3期4卷 487-504页

作者： Wendy Ann Peer joshua J. Blakeslee Haibing Yang Angus s. murphy Department of Horticulture 625 Agriculture Mall Drive Purdue University West Lafayette IN 47907 USA Department of Horticulture and Crop science Ohio Agricultural Researd and Development Center1680 Madison Avenue The Ohio State UniversityWooster OH 44691 USA

Polar transport of the phytohormone auxin and the establishment of localized auxin maxima regulate em- bryonic development, stem cell maintenance, root and shoot architecture, and tropic growth responses. The past decade has been marked by dramatic progress in efforts to elucidate the complex mechanisms by which auxin transport regulates plant growth. As the understanding of auxin transport regulation has been increasingly elaborated, it has become clear that this process is involved in almost all plant growth and environmental responses in some way. However, we still lack information about some basic aspects of this fundamental regulatory mechanism. In this review, we present what we know （or what we think we know） and what we do not know about seven auxin-regulated processes. We discuss the role of auxin transport in gravitropism in primary and lateral roots, phototropism, shoot branching, leaf expansion, and venation. We also discuss the auxin reflux/fountain model at the root tip, flavonoid modulation of auxin transport processes, and outstanding aspects of post-translational regulation of auxin transporters. This discussion is not meant to be exhaustive, but highlights areas in which generally held assumptions require more substantive validation.

关键词： Auxin transport ABCB AUX1 PIN phototropism gravitropism fountain model shoot branching leaf expansion venation flavonoids.

Ensemble-based Kalman Filters in strongly Nonlinear Dynamics

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Advances in Atmospheric sciences 2009年第3期26卷 373-380页

作者： Zhaoxia PU joshua HACKER Department of Atmospheric sciences University of Utah USA National Center for Atmospheric Research USA

This study examines the effectiveness of ensemble Kalman filters in data assimilation with the strongly nonlinear dynamics of the Lorenz-63 model, and in particular their use in predicting the regime transition that occurs when the model jumps from one basin of attraction to the other. Four configurations of the ensemble-based Kalman filtering data assimilation techniques, including the ensemble Kalman filter, en- semble adjustment Kalman filter, ensemble square root filter and ensemble transform Kalman filter, are evaluated with their ability in predicting the regime transition （also called phase transition） and also are compared in terms of their sensitivity to both observational and sampling errors. The sensitivity of each ensemble-based filter to the size of the ensemble is also examined.

关键词： ensemble Kalman filter nonlinear data assimilation Lorenz model

Correction to:Preface:special Issue on modeling,simulation,and Optimization in Operational Research

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Journal of the Operations Research society of China 2024年第2期12卷 548-548页

作者： Gerhard-Wilhelm Weber J.joshua Thomas Jose Antonio marmolejo saucedo Ugo Fiore Igor Litvinchev Pandian Vasant Poznan University of Technology PoznanPoland Institute of Applied mathematics Middle East Technical UniversityAnkaraTurkey UOW malaysia KDU Penang University CollegePetaling JayaMalaysia Facultad de Ingenieria Universidad PanamericanaMexico CityMexico Parthenope University and at Federico II University NaplesItaly Nuevo Leon state University San Nicolas de los GarzaMexico mERLIN Research Centre Ton Duc Thang UniversityHo Chi Minh CityVietnam