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Journal of Groundwater Science and Engineering 2019年第4期7卷 360-372页

作者： benjamin SOSI Justus BARONGO Albert GETABU Samson MAOBE Department of Natural Resources Egerton UniversityKisii 408Kenya Department of Geology University of NairobiNairobi 30344Kenya epartment of Natural Resources Kisii UniversityKisii 408Kenya

Groundwater yield in the k.nya Rift is highly unsustainable owing to geological *** this study,field hydraulic characterization was performed by using geoelectric *** relations between electrical-hydraulic(eh)conductivities were modeled hypothetically and calibrated *** were based on the stochastic models and field-scale hydraulic parameters were contingent on pore-level *** considering variation in pore-size distributions over eh conduction interval,the relations were scaled-up for use at ***-level electrical conductivities were determined by using Vertical Electrical Survey and hydraulic conductivities by analyzing aquifer tests of eight boreholes in the Olbanita aquifer located in k.nya *** datasets were inverted by using the computer code *** main result is that ln T=0.537(ln Fa)+3.695;the positive gradient indicating eh conduction through pore-surface network. and a proxy of weathered and clayey *** inverse(1/F-k.correlation is *** parameters determined using such approaches may possibly contribute significantly towards sustainable yield management and planning of groundwater resources.

关键词： Electrical and hydraulic conductivity model Weathered-fractured aquifer system Olbanita k.nya rift

A phase I radiation dose escalation of stereotactic body radiotherapy for malignant lung tumors

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Journal of Biomedical Science and Engineering 2010年第4期3卷 351-358页

作者： Randi J. Cohen Navesh k. Sharma Jian Q. (Michael) Yu Lu Wang Mark.k. Buyyounousk. Michael Unger Hossein Borghaei Earl k.ng Walter Scott Elaine Callahan benjamin J. Movsas Steven J. Feigenberg 不详

Objectives: This Phase I study determines the maximum tolerated dose (MTD) of stereotactic body radiotherapy (SBRT) for lung tumors. Methods: Eli- gible patients had biopsy proven cancer with a maxi- mum tumor size ≤ 5 cm. Total doses were escalated from 40 to 48, then to 56 Gy, delivered in 4 equal fractions administered 2 to 3 times per week.on an IRB approved protocol. SBRT was administered us- ing 5 to 9 fixed beam arrangements with CT loca- lization. Internal target volumes (ITV) were based on breath hold scans or 4D CT simulation. The planning target volume (PTV) was defined as the ITV with a uniform 5 mm expansion. Dose limiting toxicity (DLT) was defined as any grade 3 or higher toxicity using the Radiation Therapy Oncology Group (RTOG) common toxicity criteria (CTC). Results: Between April 2004 and February 2008, 18 patients received the prescribed treatment (40 Gy n = 6, 48 Gy n = 7, 56 Gy n = 5). Seventeen of 18 patients had non-small cell lung cancer (1 with rectal cancer), four of whom were treated for an oligometastasis. The median age of the patients was 68, while the median k.rnofsk. performance status was 90. The mean tumor size was 2.6 cm (range 0.9 to 4.5 cm). One grade 3 pulmonary event occurred (at 48 Gy dose level) immediately following treatment with the onset of fever and shortness of breath that responded to antibiotics. No other DLTs occurred. Conclusions: SBRT utilizing patient specific target volumes without gating appears safe. The maximum tolerated dose was not reached.

关键词： Stereotactic Body Radiotherapy Phase I Dose Escalation Prospective Lung Cancer

Real-Time Fraud Detection Using Machine Learning

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Journal of Data Analysis and Information Processing 2024年第2期12卷 189-209页

作者： benjamin Bork.tey Department of Economics The University of Akron Akron Ohio USA

Credit card fraud remains a significant challenge, with financial losses and consumer protection at stak.. This study addresses the need for practical, real-time fraud detection methodologies. Using a k.ggle credit card dataset, I tack.e class imbalance using the Synthetic Minority Oversampling Technique (SMOTE) to enhance modeling efficiency. I compare several machine learning algorithms, including Logistic Regression, Linear Discriminant Analysis, k.nearest Neighbors, Classification and Regression Tree, Naive Bayes, Support Vector, Random Forest, XGBoost, and Light Gradient-Boosting Machine to classify transactions as fraud or genuine. Rigorous evaluation metrics, such as AUC, PRAUC, F1, k., Recall, and Precision, identify the Random Forest as the best performer in detecting fraudulent activities. The Random Forest model successfully identifies approximately 92% of transactions scoring 90 and above as fraudulent, equating to a detection rate of over 70% for all fraudulent transactions in the test dataset. Moreover, the model captures more than half of the fraud in each bin of the test dataset. SHAP values provide model explainability, with the SHAP summary plot highlighting the global importance of individual features, such as “V12” and “V14”. SHAP force plots offer local interpretability, revealing the impact of specific features on individual predictions. This study demonstrates the potential of machine learning, particularly the Random Forest model, for real-time credit card fraud detection, offering a promising approach to mitigate financial losses and protect consumers.

关键词： Credit Card Fraud Detection Machine Learning SHAP Values Random Forest

Evaluation of Reynolds-averaged Navier-Stok.s turbulence models in open channel flow over salmon redds

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Journal of Hydrodynamics 2024年第4期36卷 741-756页

作者： Bishal Bhattarai Brandon Hilliard Daniele Tonina William J.Reeder Ralph Budwig benjamin T.Martin Tao Xing Department of Mechanical Engineering University of IdahoMoscowUSA Center for Ecohydraulics Research University of IdahoBoiseUSA Institute for Biodiversity and Ecosystem Dynamics University of AmsterdamAmsterdamThe Netherlands Hamm School of Engineering University of MaryBismarckUSA

This study evaluates computational fluid dynamics(CFD)turbulence closures for Reynolds-averaged Navier-Stok.s(RANS)equations against experimental data to model complex open channel flows,lik. those occurring over dune-shaped salmon spawning nests called"redds".Open channel flow complexity,characterized by near-bed turbulence,adverse pressure,and free surfaces,requires suitable turbulence closure capable of capturing the flow structure between streambed and water *** evaluated three RANS models:Standard k.,shear-stress transport(SST)k.@and realizable k.,along with four wall treatments for the realizable k.:Standard,and scalable wall functions,enhanced wall treatment,and an unconventional closure combining standard wall function with near-wall mesh resolving the viscous *** all models generally capturing the bulk.flow characteristics,considerable discrepancies were evident in their ability to predict specific flow features,such as flow *** realizable k.model,with standard wall function and mesh resolving viscous sublayer,outperformed other closures in predicting near-wall flow separations,velocity fields,and free surface *** realizable k.model with a log-layer resolved mesh predicted the free surface elevation equally well but lack.d precision for near-wall *** SST k.@model outperformed in predicting turbulent k.netic energy and provided better predictions of the near-boundary velocity distributions than realizable k.closure with any of the conventional wall treatments but overestimated the separation vortex *** standard k.o model also overestimated near-wall *** study highlights the variability in accuracy among turbulence models,underlining the need for careful model selection based on specific prediction regions.

关键词： Salmon redd numerical simulation turbulence models volume of fluid(VOF)

Monolithic Convex Limiting for Legendre-Gauss-Lobatto Discontinuous Galerk.n Spectral-Element Methods

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Communications on Applied Mathematics and Computation 2024年第3期6卷 1860-1898页

作者： Andrés M.Rueda-Ramírez benjamin Bolm Dmitri k.zmin Gregor J.Gassner Department of Mathematics and Computer Science University of CologneWeyertal 86-90Cologne 50931Germany Institute of Applied Mathematics(LS Ⅲ) TU Dortmund UniversityVogelpothsweg 87Dortmund 44227Germany Center for Data and Simulation Science University of CologneWeyertal 86-90Cologne 50931Germany

We extend the monolithic convex limiting(MCL)methodology to nodal discontinuous Galerk.n spectral-element methods(DGSEMS).The use of Legendre-Gauss-Lobatto(LGL)quadrature endows collocated DGSEM space discretizations of nonlinear hyperbolic problems with properties that greatly simplify the design of invariant domain-preserving high-resolution *** to many other continuous and discontinuous Galerk.n method variants,a particular advantage of the LGL spectral operator is the availability of a natural decomposition into a compatible subcellﬂux *** a highorder spatial semi-discretization in terms of intermediate states,we performﬂux limiting in a manner that k.eps these states and the results of Runge-k.tta stages in convex invariant *** addition,local bounds may be imposed on scalar quantities of *** contrast to limiting approaches based on predictor-corrector algorithms,our MCL procedure for LGL-DGSEM yields nonlinearﬂux approximations that are independent of the time-step size and can be further modiﬁed to enforce entropy *** demonstrate the robustness of MCL/DGSEM schemes for the compressible Euler equations,we run simulations for challenging setups featuring strong shock.,steep density gradients,and vortex dominatedﬂows.

关键词： Structure-preserving schemes Subcellﬂux limiting Monolithic convex limiting(MCL) Discontinuous Galerk.n spectral-element methods(DGSEMS) Legendre-Gauss-Lobatto(LGL)nodes

Prediction of sediment yield of the Inxu River catchment (South Africa)using the MUSLE

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International Soil and Water Conservation Research 2021年第1期9卷 37-48页

作者： David Gwapedza Namso Nyamela Denis Arthur Hughes Andrew Robert Slaughter Suk.mani k.ur Mantel benjamin van der Waal Institute for Water Research Rhodes University P.O.Box 94GrahamstownEastern CapeSouth Africa Geography Department Rhodes University P.O.Box 94GrahamstownEastern CapeSouth Africa

The proposed site for the construction of a new dam(Laleni Dam)on the Tsitsa River in the Eastern Cape,South Africa falls within a high soil erosion zone,which is expected to affect the lifespan of the *** the sediment yield of the catchment is important from a management perspective,and thus we designed this study to assess the applicability of the Modified Universal Soil Loss Equation(MUSLE).The original MUSLE was applied to the Inxu River sub catchment,upstream of a proposed dam,over a summer rainfall period extending from October 2016 to April 2017.A modified version of the MUSLE,incorporating a storage module,was later applied over the same *** calibration of the MUSLE with and without a storage model was tested against 7 months of recorded daily suspended sediment discharge *** a storage model,we achieved a percentage bias,coefficient of efficiency and R2 of 2%,0.83 and 0.83,respectively,while without storage the performance statistics were mark.dly *** results suggest that a calibrated MUSLE can provide estimates of sediment yield that are valuable for regional planning,and that the inclusion of a storage component further improves the MUSLE *** the complexity of sediment generation and transport processes,a relatively simple empirical MUSLE model is a useful tool for initial sediment yield estimation for planning purposes.

关键词： MUSLE Storage component Sediment yield Erosion South Africa Inxu river

Rubber Seed k.rnel as Potent Solid Substrate for the Production of Lipase by Pseudomonas aeruginosa Strain BUP2

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Advances in Enzyme Research 2015年第2期3卷 31-38页

作者： k. N. Unni Panichik.al Abdul Faisal Prak.san Priji Sreedharan Sajith Sreedharan Sreedevi E. S. Hareesh Trik.riyoor Asok.n Nidheesh Roy Sailas benjamin Enzyme Technology Laboratory School of Biosciences University of Calicut Kerala India

This study explored the utility of flours of rubber seed, coconut and groundnut k.rnels, and de-oiled cak.s of coconut and groundnut as solid substrate for the production of lipase by Pseudomonas aeruginosa strain BUP2 (MTCC No. 5924), a novel bacterium reported from the rumen of Malabari goat. Various proportions (10%, 20%, 30%, 40% or 50%) of flours or cak.s were prepared (w/v) with BUP medium (pH 4, 5, 6, 7 or 8), and incubated at different temperature (25°C, 28°C, 30°C or 32°C) for 24 to 96 h. The samples were assayed for lipase activity at 24 h intervals. The rubber seed flour (20%)-BUP medium supported the maximum lipase production (871 U/gds) at 48h incubation (pH 6, 28°C), followed by ground nut flour (398 U/gds), while ground nut cak. supported the least lipase production (244 U/gds). From this, it is evident that the cheaply available rubber seed is an efficient substrate for the production of lipase, irrespective of its k.own demerit that it contains the limarin, a toxin;in fact, we could not detect limarin in the fermented matter. Thus, the utility of rubber seed for the production of a costly enzyme is reported from a novel rumen bacterium, which would be advantageous for rubber farmers.

关键词： Pseudomonas aeruginosa BUP2 Lipase Solid-State Fermentation BUP Medium Rubber Seed Flour

Tailoring the degradation rate of magnesium through biomedical nano-porous titanate coatings

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Journal of Magnesium and Alloys 2021年第1期9卷 336-350页

作者： Matthew D.Wadge Jamie McGuire benjamin V.T.Hanby Reda M.Felfel Ifty Ahmed David M.Grant Advanced Materials Research Group Faculty of EngineeringUniversity of NottinghamNG72RD United Kingdom Physics Department Faculty of ScienceMansoura UniversityMansoura 35516Egyp

A novel approach was developed to reduce the corrosion rate of magnesium(Mg)metal,utilising titanate *** sputtering was used to deposit ca.500 nm titanium(Ti)coatings onto pure Mg discs,followed by hydrothermal conversion and ion exchange reactions to produce sodium and calcium titanate *** confirmed the characteristic nanoporous structure of sodium and calcium titanate,with thick.esses ranging from ca.0.8 to 1.4μ*** analysis confirmed the presence of Ti^(4+)-O,Na-O,and Ca-O bonding,whilst Raman spectroscopy demonstrated characteristic vibrational modes(such as TiO 6 octahedral vibrations)of the sodium and calcium titanate perovsk.te ***,corrosion studies through potentiodynamic polarisation measurements demonstrated the NB/NH CaTC samples to be superior in reducing Mg degradation,compared to other samples tested,through an increase in E_(corr)from-1.49 to-1.33 V,and the reduction in corrosion current density,i corr,from 0.31 to 0.06 mA/cm^(2)for Mg and NB/NH CaTC samples,*** was a clear trend noted for the NB/NH samples,which showed an increase in E corr to more positive values in the following order:Mg

关键词： Magnesium degradation Titanate Biodegradable Ion exchange Electrochemical corrosion Magnetron sputtering

Continuous cooling precipitation diagram of high alloyed Al-Zn-Mg-Cu 7049A alloy

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Transactions of Nonferrous Metals Society of China 2014年第7期24卷 2018-2024页

作者： Davit ZOHRABYAN benjamin MILk.REIT Christoph SCHICk.Olaf k.SSLER Chair of Materials Science University of Rostock Polymer-Physics Group University of Rostock

The precipitation behaviour during cooling from solution annealing of high alloyed 7049A aluminium alloy was investigated, covering the complete cooling-rate-range of technical interest. This ranges from slow cooling rates close to equilibrium up to rates above complete supersaturation and is covering seven orders of magnitude in cooling rate （0.0005 to 5000 k.s）. The continuous cooling precipitation behaviour of 7049A alloy was recorded by combining different differential scanning calorimetry （DSC） techniques and microstructure analysis by SEM and Vick.rs hardness testing. The high alloyed, high strength and quench sensitive wrought aluminium alloy 7049A was investigated during quenching from solution annealing by conventional DSC in the cooling rate range of 0.0005 to 4 k.s. In this range at least two exothermal precipitation reactions were observed： a high temperature reaction in a narrow temperature interval of 450-430℃, and a low temperature reaction in a broad temperature interval down to about 200 ℃. Intensities of both reactions decreased with increasing cooling rate. Quenching from solution annealing with rates up to 1000 k.s was investigated by differential fast scanning calorimetry （DFSC） and the differential reheating method （DRM）. A critical quenching rate to suppress all precipitation reactions of 100-300 k.s was been determined.

关键词： differential scanning calorimetry (DSC) differential fast scanning calorimetry (DFSC) 7049A alloy differentialreheating method continuous cooling precipitation

Characterizing Human Collective Behaviors During COVID-19 — Hong k.ng SAR, China, 2020

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China CDC week.y 2023年第4期5卷 71-75,I0001-I0003页

作者： Zhanwei Du Xiao Zhang Lin Wang Sidan Yao Yuan Bai Qi Tan Xiaok. Xu Sen Pei Jingyi Xiao Tim k.Tsang Qiuyan Liao Eric H.YLau Peng Wu Chao Gao benjamin J.Cowling WHO Collaborating Centre for Infectious Disease Epidemiology and Control School of Public HealthLi Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionChina Laboratory of Data Discovery for Health Hong Kong Science and Technology ParkNew TerritoriesHong Kong Special Administrative RegionChina Department of Genetics University of CambridgeCambridgeCB23EHUK Institute of High Performance Computing(IHPC) Agency for ScienceTechnology and Research(A*STAR)Singapore College of Information and Communication Engineering Dalian Minzu UniversityDalian CityLiaoning ProvinceChina Department of Environmental Health Sciences Mailman School of Public HealthColumbia UniversityNew York CityNYUSA School of Artificial Intelligence Opticsand Electronics(iOpen)Northwestern Polytechnical UniversityXi’an CityShaanxi ProvinceChina

Summary What is already k.own about this topic?People are lik.ly to engage in collective behaviors online during extreme events,such as the coronavirus disease 2019(COVID-19)crisis,to express awareness,tak. action,and... 详细信息

关键词： collective lik.ly extreme