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Estimating REY content of eastern Kentucky coal samples based on their associated ash elements

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Journal of Rare Earths 2018年第11期36卷 1234-1238页

作者： s.Chehreh Chelgani james C.Hower Department of Electrical Engineering and Computer science University of Michigan Center for Applied Energy Research University of Kentucky

Coal and coal combustion byproducts can be considered as an alternative source of rare earth elements and yttrium （REY）. The study of relationships between REY and other main coal properties could have several advantages such as estimating REY content of coal particles and designing beneficial extraction method. In this investigation, inter-correlations between REY content with coal parameters （proximate and ash elements） for a wide range of eastern Kentucky coal samples （708 records） were explored. Results demonstrate that zircon and monazite are the main source of heavy and light rare earth elements （HREE and LREE）, respectively. Zr has the highest correlation with Y and Th has the strength relationship with Ce and La. In general, LREE have higher interaction with coal ash content in comparison with HREE. Results indicated that REY can be estimated quite satisfactorily by using their associated elements in coal ash.

关键词： Coal Heavy rare earth Light rare earth Proximate Ash elements

The effect of top managers'years of experience on innovation

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International Journal of Innovation studies 2023年第3期7卷 226-235页

作者： james Okrah Bridget Irene Research Engineer Graduate School of Economics and ManagementUral Federal UniversityYekaterinburgRussia CMI Fellow IHEA Fellow Assistant Professor of Entrepreneurship Course Director BA Enterprise and Entrepreneurship Coventry UniversityCoventryCV15DLUK

Managers'characteristics have been identified to have an influence on how they perceive *** study examines the role of top managers'experience and how it influences their propensity to *** employs a logit model to analyze data from the World Bank's Enterprise surveys,primarily from small-and medium-sized enterprises in *** justify the positive effect of managers'years of experience as an influential factor of enterprises'innovativeness in developing *** results show that top managers'years of experience directly affect innovation.

关键词： Russia Innovation Top-level management experience sMEs Firms Bureaucracy Weak institutions

Evolution of continent ileostomy

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World Journal of Gastroenterology 2012年第27期18卷 3479-3482页

作者： Gurel Nessar james s Wu Department of Gastrointestinal surgery Yuksek Ihtisas HospitalAnkara 06100Turkey Department of Colorectal surgery Digestive Disease InstituteClevelandOH 44195United States

Continent ileostomy can be defined as a surgical procedure that facilitates planned intermittent evacuation of a bowel reservoir through an *** was devised by Nils Kock in ***,continent ileostomy (or Kock pouch) became a viable alternative in the management of patients who had traditionally required an end *** pouch appeared to provide substantial physical and psychosocial benefits over a conventional *** procedure became popular until ileal pouch anal anastomosis (IPAA) was introduced in *** its benefits,continent ileostomy had many short term complications including intubation problems,ileus,anastomotic leaks,peritonitis and valve *** mortalities have also been reported in the *** of these problems have been eliminated with increasing experience;however,valverelated problems remain as an "Achilles' heel" of the *** modifications have been introduced to prevent this *** patients have had their pouch removed because of complications mainly related to valve *** revision rates can be high,most of the patients who retain their reservoirs are satisfied with regard to their health status and quality of ***,this procedure is still appropriate for selected patients for whom pouch surgery is not possible or for patients who have failed *** the patient and their physician must be highly motivated to accept the risk of failure and the subsequent need for revisional operations.

关键词：回肠大陆演变气管插管生活质量健康状况并发症患者

Does climate change alter the nutrient trends of Cedrela fissilis Vell. trees in the southern Brazilian Amazon?

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Ecological Processes 2023年第4期12卷 164-185页

作者： Daigard R.Ortega Rodriguez Raúl sánchez-salguero Andrea Hevia Renata C.Bovi Marciel J.Ferreira james H.speer Fidel A.Roig Mario Tomazello-Filho Escola superior de Agricultura Luiz de Queiroz Departamento de Ciências Florestais Universidade de S?o Paulo Dendr Olavide-Department sistemas Físicos Químicos y Naturales Universidad Pablo de Olavide Department of Ecology Universidad de Jaén Campus Las Lagunillas s/n. Departamento de Ciência Florestal Solos e AmbienteUniversidade Estadual Paulista Laboratory of silviculture Universidade Federal do Amazonas Department of Earth and Environmental systems Indiana State University Argentine Institute of Nivology Glaciology and Environmental Sciences(IANIGLA CONICET Universidad Nacional de Cuyo) Hémera Centro de Observación de la Tierra Escuela de Ingeniería Forestal Facultad de CienciasUniversidad Mayor

Background The increase in the frequency and intensity of droughts is pointed out as one of the main factors altering biogeochemical cycles in the Amazon basin. An eco-nutritional approach using X-ray fluorescence micro-analysis(μXRF) is proposed to verify the long-and short-term effects of droughts on the growth and xylem nutrient concentrations of Cedrela fissilis *** Fourteen radii were selected from a tree-ring width chronology and X-rayed by Itrax Multiscanner. Profiles of ring width, wood density, and concentrations of aluminum(Al), phosphorus(P), sulfur(s), calcium(Ca), potassium(K), manganese(Mn), iron(Fe) and strontium(sr) together with Al/Ca, Ca/Mn, K/Ca, sr/Ca and Mn/s ratios were constructed and correlated with precipitation, temperature, the difference between precipitation and potential evapotranspiration(P-PET) and standardized precipitation–evapotranspiration index(sPEI).Results During dry years, C. fissilis showed narrower, less dense rings, lower Al, P, s and Ca, and higher K and Fe concentrations(the opposite was found in wet years). Ring width decreased(together with Al, P, s, K, Ca, Mn, Fe, sr, Al/Ca, K/Ca and sr/Ca) and wood density increased(together with Ca/Mn and Mn/s), which was associated with an increase in evapotranspiration and temperature over time, mainly since 1990. Cedrela fissilis showed a tendency to increase its capacity for resistance, and a recovery and resilience in growth over time associated with responses in Al, Ca, P and s. However, it showed a risk in the capacity for recovery of the pre-drought density values, associated with unsatisfactory responses in Al, Ca, K, Fe and *** This study is the first attempt to analyze tree-ring nutritional evidences of C. fissilis trees to climate sensitivity and resilience to drought, based on long-term data from seasonal moist tropical forests of the Amazon. Our data suggested that C. fissilis is undergoing alterations in the concentration, use and redistribution of n

关键词： Dendrochemistry µXRF Drought Tropical tree Eco-chemical indicator Resilience Resistance Recovery

Bioreactor design and validation for manufacturing strategies in tissue engineering

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Bio-Design and Manufacturing 2022年第1期5卷 43-63页

作者： Diana Lim Eric s.Renteria Drake s.sime Young Min Ju Ji Hyun Kim Tracy Criswell Thomas D.shupe Anthony Atala Frank C.Marini Metin N.Gurcan shay soker Joshua Hunsberger james J.Yoo Wake Forest Institute for Regenerative Medicine Wake Forest School of MedicineWinston-SalemNC 27157USA Center for Biomedical Informatics Wake Forest School of MedicineWinston-SalemNC 27157USA RegenMed Development Organization(ReMDO) Winston SalemNC 27106USA

The fields of regenerative medicine and tissue engineering offer new therapeutic options to restore,maintain or improve tissue function following disease or *** maximize the biological function of a tissue-engineered clinical product,specific conditions must be maintained within a bioreactor to allow the maturation of the product in preparation for ***,the bioreactor should be designed to mimic the mechanical,electrochemical and biochemical environment that the product will be exposed to in ***-time monitoring of the functional capacity of tissue-engineered products during manufacturing is a critical component of the quality management *** present review provides a brief overview of bioreactor engineering *** addition,strategies for bioreactor automation,in-line product monitoring and quality assurance are discussed.

关键词： Bioreactor Monitoring sensors and automation Manufacturing Tissue engineering Regenerative medicine

A Comparison of PPO, TD3 and sAC Reinforcement Algorithms for Quadruped Walking Gait Generation

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Journal of Intelligent Learning systems and Applications 2023年第1期15卷 36-56页

作者： james W. Mock suresh s. Muknahallipatna Department of Electrical Engineering and Computer science University of Wyoming Laramie Wyoming USA

Deep reinforcement learning (deep RL) has the potential to replace classic robotic controllers. state-of-the-art Deep Reinforcement algorithms such as Proximal Policy Optimization, Twin Delayed Deep Deterministic Policy Gradient and soft Actor-Critic Reinforcement Algorithms, to mention a few, have been investigated for training robots to walk. However, conflicting performance results of these algorithms have been reported in the literature. In this work, we present the performance analysis of the above three state-of-the-art Deep Reinforcement algorithms for a constant velocity walking task on a quadruped. The performance is analyzed by simulating the walking task of a quadruped equipped with a range of sensors present on a physical quadruped robot. simulations of the three algorithms across a range of sensor inputs and with domain randomization are performed. The strengths and weaknesses of each algorithm for the given task are discussed. We also identify a set of sensors that contribute to the best performance of each Deep Reinforcement algorithm.

关键词： Reinforcement Learning Machine Learning Markov Decision Process Domain Randomization

Methodology to locate and quantify radial winding deformation in power transformers

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High Voltage 2017年第1期2卷 17-24页

作者： steven D.Mitche james s.Wesh school of Electrical and Computer Engineering University of NewcastleCallaghanN.S.W 2308Australia

Frequency response analysis(FRA)is a tool that can be used to detect changes within the structural geometry of a *** application of FRA is to detect winding displacement after the transformer experiences an overcurrent *** paper proposes a methodology which will facilitate both locating and quantifying winding *** procedure is based on the fitting of a Gray Box transformer model to FRA measurements which were recorded both before and after the *** variation in key parameters of the model can then be used to quantify winding deformation *** research will demonstrate the applicability of this approach to a wide range of transformer applications by using FRA from a modified 1.3 MVA distribution transformer,and assessing the change in key parameters relative to the emulated buckling introduced to the *** authors propose that this approach is ideally suited for use within an automated diagnostic system which will locate,diagnose and quantify winding deformation within power transformers.

关键词： winding deformation power

Generating high-resolution climate maps from sparse and irregular observations using a novel hybrid RBF network

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Big Earth Data 2023年第4期7卷 1120-1145页

作者： Yue Han Zhihua Zhang M.james C.Crabbe Climate Modeling Laboratory School of MathematicsShandong UniversityJinanChina MOE Key Laboratory of Environmental Change and Natural Disaster Beijing Normal UniversityBeijingChina Wolfson College Oxford UniversityOxfordUK

sparse and irregular climate observations in many developing countries are not enough to satisfy the need of assessing climate change risks and planning suitable mitigation *** wideused statistical downscaling model(sDsM)software tools use multi-linear regression to extract linear relations between largescale and local climate variables and then produce high-resolution climate maps from sparse climate *** latest machine learning techniques(***,sRGAN)can extract nonlinear links,but they are only suitable for downscaling low-resolution grid data and cannot utilize the link to other climate variables to improve the downscaling *** this study,we proposed a novel hybrid RBF(Radial Basis Function)network by embedding several RBF networks into new RBF *** model can well incorporate climate and topographical variables with different resolutions and extract their nonlinear relations for spatial *** test the performance of our model,we generated high-resolution precipitation,air temperature and humidity maps from 34 meteorological stations in *** terms of three statistical indicators,the accuracy of high-resolution climate maps generated by our hybrid RBF network clearly outperformed those using a multi-linear regression(MLR),Kriging interpolation or a pure RBF network.

关键词： Hybrid RBF network climate map sparse observed climate data high resolution

Correcting for spatially dependent intrinsic efficiency on a germanium double-sided strip detector to improve nuclear forensics response

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Radiation Detection Technology and Methods 2022年第1期6卷 78-87页

作者： Timothy Jacomb-Hood james Fast Craig Department of Nuclear Engineering Texas A&M UniversityCollege StationTXUSA Pacific Northwest National Laboratory RichlandWAUSA

Purpose The Germanium Gamma-ray Imager(GeGI)is a planar high-purity germanium(HPGe)imaging detector developed by PHDs Co for far-field *** research investigates the detector’s ability for measuring heterogeneous sources in the near field,placed directly on the detector’s faceplate,to perform isotopic mapping for nuclear forensic *** The intrinsic efficiency is strongly dependent on where the photons interact within the *** efficiency varies by up to 20%within the sensitive volume of the *** efficiency was mapped using eight different photons from 123 to 1274 keV emitted from a collimated 154Eu *** were measured at 108 locations to interpolate the efficiency at any point on the detector’s *** The position and energy dependence are uncorrelated,and thus,the absolute efficiency at any position and for any gamma-ray energy can be calculated by the convolution of the spatial and energy *** The results on this research show that detection efficiency for a planar two-sided strip HPGe is spatially dependent and shows typical energy *** spatial dependence,which does not have any additional energy dependence,can be corrected.A 154Eu source was used in this research and was able to spatially calibrate for photon energies ranging from 100 to 1300 *** method is applicable for sources with higher gamma *** advantages of the method demonstrated that after initial in-laboratory calibration,a single measurement in the field can be used to efficiently calibrate the HPGe as a function of photon interaction on the crystal.

关键词： Nuclear forensics Radiation detection Gamma-ray imaging