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Frontiers of Chemical Science and engineering 2021年第3期15卷 552-561页

作者： Hongzhan Di Gregory J.O.Martin dave e.dunstan Department of Chemical and Biomolecular engineering University of MelbourneParkvilleVictoria 3010Australia

Particle deposition during crossflow filtration is significantly influenced by the operating conditions,in particular the permeate flux and crossflow ***,there is a lack of detailed knowledge about how deposit layer structures and distributions depend on operating *** study uses a microfluidic visualisation filtration system to examine the influence of operating conditions on the deposition process during crossflow ultrafiltration from a microscopic *** the permeate flux caused an increasing amount of deposition and a thicker deposit *** crossflow velocities reduced the extent of *** degree of deposition varied over a range of operating conditions due to the altered hydrodynamic forces exerted on the particles,which can be examined by the deposition probability according to an existing *** on this,an empirical correlation between the deposition probability and volume of deposition as a function of filtration time was developed,which gave good agreement with experimental *** effect of solution conditions was also involved in this correlation as a interaction *** could be useful for predicting the dynamic deposition process during crossflow filtration over a range of operating and solution conditions.

关键词： particle deposition crossflow filtration microfluidics confocal microscopy

evaluation of the cracking and aging susceptibility of asphalt mixtures using viscoelastic properties and master curve parameters

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Journal of Traffic and Transportation engineering(english edition) 2022年第1期9卷 106-119页

作者： Runhua Zhang Jo e.Sias eshan V.dave Department of Civil and environmental engineering University of New HampshireDurhamNH 03824USA

Aging can significantly affect the performance of asphalt mixtures, causing increase in stiffness, reduction in relaxation capability and increase in cracking susceptibility. It is also well known that fundamental viscoelastic properties are used for design and modelling of asphalt mixtures and pavement structures to addressing rutting, fatigue and thermal cracking concerns. The objective of this paper is to study how the viscoelastic properties of asphalt mixture change over time, and evaluate and identify the cracking and aging susceptibility of asphalt mixtures with different mix variables during material selection and mixture design. Ten mixtures are evaluated using different laboratory conditioning protocols to simulate a range of aging levels in the field. The complex modulus test is then conducted on the lab aged mixtures to measure the viscoelastic properties in order to construct the dynamic modulus and phase angle master curves. The mixture Glover-Rowe(G-Rm) parameter and the shape parameters of the dynamic modulus and phase angle master curves, including inflection point frequency(-β/γ), difference between the glassy modulus and the inflection point modulus(γ), peak value of phase angle(a) and the horizontal position(frequency) of the peak phase angle value(c), are determined and evaluated for the mixtures with different aging conditions and mix variables. The study indicates the ability of the G-Rmparameter and all the master curve shape parameters to capture the effect of different aging conditions on linear viscoelastic mixture properties, as well as the cracking and aging susceptibility of asphalt mixtures.

关键词： Asphalt mixture Viscoelastic properties Complex modulus and phase angle master curve Master curve shape parameters Aging susceptibility Cracking susceptibility

IQR-based approach for DDoS detection and mitigation in SDN

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Defence Technology（防务技术） 2023年第7期25卷 76-87页

作者： Rochak Swami Mayank dave Virender Ranga Department of Computer engineering National Institute of TechnologyKurukshetraIndia Department of Information Technology Delhi Technological UniversityDelhiIndia

Software-defined networking(SDN) is a trending networking paradigm that focuses on decoupling of the control logic from the data plane. This decoupling brings programmability and flexibility for the network management by introducing centralized infrastructure. The complete control logic resides in the controller, and thus it becomes the intellectual and most important entity of the SDN infrastructure. With these advantages, SDN faces several security issues in various SDN layers that may prevent the growth and global adoption of this groundbreaking technology. Control plane exhaustion and switch buffer overflow are examples of such security issues. Distributed denial-of-service(DDoS) attacks are one of the most severe attacks that aim to exhaust the controller’s CPU to discontinue the whole functioning of the SDN network. Hence, it is necessary to design a quick as well as accurate detection scheme to detect the attack traffic at an early stage. In this paper, we present a defense solution to detect and mitigate spoofed flooding DDoS attacks. The proposed defense solution is implemented in the SDN controller. The detection method is based on the idea of an statistical measure — Interquartile Range(IQR). For the mitigation purpose, the existing SDN-in-built capabilities are utilized. In this work, the experiments are performed considering the spoofed SYN flooding attack. The proposed solution is evaluated using different performance parameters, i.e., detection time, detection accuracy, packet_in messages, and CPU utilization. The experimental results reveal that the proposed defense solution detects and mitigates the attack effectively in different attack scenarios.

关键词： SDN DdoS IQR Controller CPU utilization Packet_in

Impact Assessment and Mitigation Techniques for High Penetration Levels of Renewable energy Sources in Distribution Networks:Voltage-control Perspective

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Journal of Modern Power Systems and Clean energy 2022年第2期10卷 450-458页

作者： Ahmed S.A.Awad dave Turcotte Tarek H.M.el-Fouly Natural Resources Canada Can-metENERGYVarennesCanadaon leave from the Electrical Power and Machines DepartmentFaculty of EngineeringAin Shams UniversityCairo 11566Egyp Natural Resources Canada CanmetENERGYVarennesCanada Advanced Power and energy Center Khalifa UniversityAbu DhabiUnited Arab Emirates

The integration of renewable distributed generation(RDG)into distribution networks is promising and increasing ***,high penetration levels of distributed generation(DG)are often limited as they may have an adverse effect on the operation of distribution *** of the operation challenges is the interaction between DG and voltage-control equipment,e.g.,an under-load tap changer(ULTC),which is basically designed to compensate for voltage changes caused by slow load *** integration of variable DGs leads to rapid voltage fluctuations,which can negatively affect the tap operation of *** paper investigates the impact of high penetration levels of RDG on the tap operation of ULTC in distribution networks through *** mitigation techniques that can alleviate this impact are also *** these techniques,constant power-factor mode is regarded as the best trade-off between the simplicity and effectiveness of minimizing the number of tap *** are performed on a Canadian benchmark rural distribution feeder using OpenDSS software.

关键词： Renewable energy distributed generation(DG) voltage regulator load tap changer distribution network.

Intelligent transportation systems for smart cities:a progress review

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Science China(Information Sciences) 2012年第12期55卷 2908-2914页

作者： COOPeR dave e State Key Laboratory of Software Development environment School of Computer Science and EngineeringBeihang University

To better meet the challenge of providing effective,low-cost,energy efficient transport services,the concept of intelligent transport systems(ITS) has been proposed and lauded as an innovative and promising solution for next generation transport *** this paper,the progress of ITS research around the world is briefly reviewed and current challenges are outlined,thereby offering further insight into ITS development for all researchers in this area.

关键词： intelligent transportation systems traffic information smart city

Intensity of effort and momentary failure in resistance training:Are we asking a binary question for a continuous variable?

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Journal of Sport and Health Science 2022年第6期11卷 644-647页

作者： James P.Fisher James Steele dave Smith School of Sport Health and Social ScienceSolent UniversitySouthamptonSO140YNUK Research Centre for Musculoskeletal and Sports Medicine Manchester Metropolitan UniversityManchesterM156BHUK

*** There is a growing body of research supporting the idea that a plethora of health benefits can result from resistance training using a low volume,high-effort approach(e.g.,increased metabolic rate and bone mineral density,a reduction in blood pressure,and improved muscle quality and insulin sensitivity,among ***,muscular strength and muscle massprimary goals and benefits of participation in resistance trainingare independently strong predictors of longevity and quality of life. Thus,many have sought to identify how the manipulation of resistance training variables might lead to“optimal”adaptations in such outcomes,as evidenced by repeated attempts over recent decades to review the literature and provide consensus statements on this topic.5-10 One variable that is often hotly debated within resistance training is training to failure.

关键词： resistance binary continuous

Numerical investigation of the hydraulic fracturing mechanisms in oil sands

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Underground Space 2021年第2期6卷 195-216页

作者： Siavash Taghipoor Morteza Roostaei Arian Velayati Atena Sharbatian dave Chan Alireza Nouri Department of Civil and environmental engineering University of AlbertaCanada KGHM International 1010 Lorne StSudburyON P3C 4R9Canada RGL Reservoir Management Inc. 690842 StLeducAB T9E 0R8Canada

This paper presents a numerical investigation of hydraulic fracturing in oil sands during cold water injection by considering the aspects of both geomechanics and reservoir fluid *** to previous studies,the low shear strengths of unconsolidated or weakly consolidated sandstone reservoirs significantly influence the hydraulic fracturing ***,classical hydraulic fracture models cannot simulate the fracturing process in weak sandstone *** the current numerical models,the direction of a tensile fracture is predetermined based on in situ stress ***,the potential transformation of a shear fracture into a tensile fracture and the potential reorientation of a tensile fracture owing to shear banding at the fracture tip have not yet been addressed in the *** this study,a smeared fracture technique is employed to simulate tensile and shear fractures in oil *** model used combines many important fracture features,which include the matrix flow,poroelasticity and plasticity modeling,saturation-dependent permeability,gradual degradation of the oil sands as a result of dilative shear deformation,and the tensile fracturing and shear failure that occur with the simultaneous enhancement of ***,sensitivity analyses are also performed with respect to the reservoir and geomechanical parameters,including the apparent tensile strength and cohesion of the oil sands,magnitude of the minimum and maximum principal stress,absolute permeability and elastic modulus of the oil sands and ramp-up *** these analyses are performed to clarify the influences of these parameters on the fracturing response of the oil sands.

关键词： Smeared fracture Hydraulic fracturing Numerical simulation Oil sand

Degradation of Phenolic Compounds in Creosote Treated Wood Waste by A Mixed Microbial Culture Augmented with Cellulolytic- Thermophilic Actinomaycets <i>Thermobifida fusca</i>

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Journal of environmental Protection 2012年第1期3卷 83-96页

作者： Abdel e Ghaly Bopeng Zhang Deepika dave 不详

Creosote is used for preservation of railway ties and timbers, electric utility poles, marine and foundation piling, fences and garden furniture. Creosote-treated wood waste may cause potential contamination of soil and water if they are not disposed properly. Creosote contains over 300 organic compounds including polycyclic aromatic hydrocarbons, phenolic compounds and heterocyclic organic compounds, many of which are toxic to human and can cause damage to kidney, liver, eyes and skin. The feasibility of using a composting technique inoculated with the cellulose degrading actinomycetesThermobifidafusca as a mesophilic/thermophilic bioremediation option to degrade phenolic compounds in creosote treated wood waste was evaluated. The temperature profile of bioremediation process clearly identified mesophilic and thermophilic phases in both experiments. Different degradation rates were observed in the mesophilic and thermophilic phases. Fluctuations of pH was observed in both experiment as the result of the breakdown of organic nitrogen to ammonium in the first week and the formation of organic acids and the loss of ammonium with the exhaust gases in the latter stage. The moisture content decreased in both trials because of the net loss of water with the exhaust gas. Both experiments achieved similar reductions in total carbon and TKN, volatile solids and phenolic compounds, cellulose and lignin indicating similar levels of microbial activities during the composting process. The stability and maturity of the final products were also similar. The inoculation of the cellulolytic-thermophilicactinomycetesThermobifidafusca did not manifest observable differences in degrading cellulose, lignin and phenolic compounds compared with the control.

关键词： Composting Bioremediation Mesophilic Thermophilic Phenolic Compounds Wood Waste

Column Analyses of Chloride Breakthrough and Lead Retention in Amended Sandy Soils

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Journal of environmental Science and engineering(A) 2012年第4期1卷 503-513页

作者： Mark e. Grismer Michael P. Hogan dave e. Steinfeld Department of Hydrologic Sciences and Biological ＆ Agricultural engineering Davis CA 95616 USA Integrated environmental Resource Services Tahoe City CA 96145 USA USDA- Forest Service Portland OR 97204 USA

Stormwater quality design manuals lack scientifically creditable bases for many novel LID (Low-Impact Development) designs presently proposed to meet stormwater runoff management requirements. Potential stormwater pollutant adsorption and infiltration enhancement capabilities of forest-derived by-products (e. g. woodchips, bio-char) provide an opportunity to combine these readily availability materials into stormwater quality designs. On-site stormwater runoff treatment through determination of the soil-water transport and lead (Pb) retention capacity of two sandy soils from Oregon is considered. Using synthetic stormwater (~120 mg Cl/L and ~5 mg Pb/L) displacement tests in pairs of ABS (Acrylonitrile butadiene styrene) soil columns (75 mm dia by 0.46 m tall) with upward flow (to minimize air entrapment) saturated hydraulic conductivity, chloride dispersion and Pb retention by plain and amended soils is evaluated. Generally, soil amendment incorporation (woodchips, compost or biochar) as compared to an amendment layer resulted in improved hydraulic conductivities as compared to that of the soil alone. Chloride breakthrough curves verified that resident soil-water displacement occurred with 0.9 to 1.6 pore volumes and residence times for most columns were 15-30 minutes. No synthetic stormwater Pb "breakthrough" within the displaced or replaced soil-water was found, rather most Pb was adsorbed within the first 150 mm of soil.

关键词：沙质土壤土壤铅修订氯化雨水径流水力传导系数设计手册质量设计

Phytochemicals and cancer chemoprevention

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Journal of Cancer Metastasis and Treatment 2020年第1期6卷 575-610页

作者： Asim dave Falguni Parande eun-Jung Park John M.Pezzuto Arnold&Marie Schwartz College of Pharmacy and Health Sciences Long Island UniversityBrooklynNY 11201USA College of Pharmacy and Health Sciences Western New England UniversitySpringfieldMA 01119-2684USA

The unending morbidity and mortality that results from cancer,as well as adverse reactions due to chemotherapy and the enormous economic burden of treatment and hospitalization,advocates for the necessity of chemopreventive *** chemoprevention refers to the use of agents capable of reversing,reducing,or slowing down the pathology of cancer at various ***,a few therapeutic drugs with relatively low toxicity(e.g.,tamoxifen,finasteride),and a sparse number of vaccines(hepatitis B,HPV),are used to prevent specific *** the general population,however,therapeutic options for cancer prevention are not ***,it is generally agreed that diet affects the genesis of cancer,and phytochemicals have the capacity of functioning as cancer chemoprevention *** is supported by epidemiological studies and clearly documented with animal models designed to mimic human ***,some public health strategies,such as recommendations for greater consumption of fruits and vegetables,reflect the merits of cancer ***,we focus on some well-established natural product cancer chemopreventive agents,including resveratrol(grapes),epigallocatechin-3-gallate(green tea),sulforaphane(cruciferous vegetables),anthocyanins(grapes and berries),curcumin(turmeric),silibinin(milk thistle),and lycopene(tomatoes).As aptly demonstrated by genomic analysis and other methods,the mechanistic underpinning is variable and *** addition,responses may be mediated through indirect mechanisms,such as interaction with the ***,ancillary applications of chemopreventive agents are worthy of consideration,such as management of sequelae induced by *** the loss of millions of cancer patients every year,it is obvious that negating malignant metastatic conditions remains of paramount *** meeting this objective,cancer chemoprevention offers great promise.

关键词： Chemoprevention phytochemicals resveratrol curcumin anthocyanins silibinin lycopene epigallocatechin-3-gallate anti-cancer activity