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Understanding nutrient build-up on urban road surfaces

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Journal of Environmental sciences 2010年第6期22卷 806-812页

作者： Nandika Prasadani Miguntanna Ashantha goonetilleke Prasanna Egodowatta serge Kokot school of Urban Development Queensland University of Technology school of Physical and Chemical sciences Queensland University of Technology

This article discusses the outcomes of a research project on nutrients build-up on urban road surfaces. Nutrient build-up was investigated on road sites belonging to residential, industrial and commercial land use. Collected build-up samples were separated into five particle size ranges and were tested for total nitrogen （TN）, total phosphorus （TP） and sub species of nutrients, namely, NO2^-, NO3^-, TKN and PO4^3-. Multivariate analytical techniques were used to analyse the data and to develop detailed understanding on build- up. Data analysis revealed that the solids loads on urban road surfaces are highly influenced by factors such as land use, antecedent dry period and traffic volume. However, the nutrient build-up process was found to be independent of the type of land use. It was solely dependent on the particle size of solids build-up. Most of the nutrients were associated with the particle size range 〈150 μm. Therefore, the removal of particles below 150 μm from road surfaces is of importance for the removal of nitrogen and phosphorus from road surface solids build-up. It is also important to consider the difference in the composition of nitrogen and phosphorus build-up in the context of designing effective stormwater quality mitigation strategies.

关键词： nutrient pollution pollutant build-up stormwater pollution

A Rapid and Convenient synthetic Route to Novel 1,5-Benzodiazepine Derivatives of 5-Methyl-3-phenyl-2-oxo-△^4-1,3,4-oxadiazolines from ρ-Acetylphenylsydnone and Their Pharmacological Activity

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Chinese Journal of Chemistry 2006年第1期24卷 79-84页

作者： KAMBLE,ravindra R. sUDHA, Belagur s. Department of Chemistry and Food science Yuvaraja's College University of Mysore Mysore-570 005 India

A simple and high yielding method for the integration of 1,5-benzodiazepines integrated with 5-methyl- 2-oxo-3-phenyl-△^4-1,3,4-oxadiazolines in 75%-90% yield by microwave irradiation is devised. Microwave-accelerated reaction was compared with thermal method. All the compounds were characterized by physical, analytical and spectral （IR, 1^H NMR, Ms） data. Title compounds were screened for preliminary pharmacological activities.

关键词： ρ-acetylphenylsydnone 1,3-dipolar cycloaddition 1,5-diazepine Michael addition microwave irradiation thermal method

Development and experimental investigation of duplex turning process

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Advances in Manufacturing 2017年第2期5卷 149-157页

作者： ravindra Nath Yadav Department of Mechanical Engineering BBD National Institute of Technology and Management Lucknow 226028India

The aim of the present study was to develop a novel turning process with the simultaneous application of two cutting tools in place of a single cutting tool during machining of rotating surfaces. This process is referred to as duplex turning, and is used to eliminate the need for a secondary final cut operation following the turning process. To achieve this, a secondary （auxiliary） tool post is mounted on the cross slide of the centre lathe machine after fabrication. The secondary tool post is used to hold a secondary cutting tool that penetrates the workpiece from opposite side of the primary cutting tool to perform the finish cut operation during turn machining of the cylin- drical workpiece. The performance of the developed process was tested on AIsI 1040 alloy steel, using two single point cutting tools made of high speed steel. The effects of cutting velocity, feed rate, primary depth of cut and secondary depth of cut were analyzed and discussed with regard to average surface roughness, and were also compared with normal turning process. From the results, it was concluded that duplex turning process was capable of providing better surface finishes compared to those generated by normal turning. It was also found that higher cutting velocity yielded better surface finishes within the determined ranges of the selected parameters.

关键词： Cutting Design of experiment Machining surface roughness Turning

A Critical Review of social Resilience Properties and Pathways in Disaster Management

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International Journal of Disaster Risk science 2021年第6期12卷 790-804页

作者： A.M.Aslam saja Melissa Teo Ashantha goonetilleke Abdul MZivath Faculty of Engineering.south Eastern University of sri Lanka Oluvil 32360Sri Lanka science and Engineering Faculty.Queensland University of Technology(QUT) Brisbane.Queensland 4001Australia Zedz Consultants Pty Ltd HillcrestQLD 4118Australia

Resilience as a concept is multi-faceted with complex *** a disaster context,there is lack of consistency in conceptualizing social *** results in ambiguity of its definition,properties,and pathways for assessment.A number of key research gaps exist for critically reviewing social resilience conceptualization,projecting resilience properties in a disaster-development continuum,and delineating a resilience trajectory in a multiple disaster *** review addressed these research gaps by critically reviewing social resilience definitions,properties,and *** review found four variations in social resilience definitions,which recognize the importance of abilities of social systems and processes in disaster phases at different levels.A review of resilience properties and pathways in the disaster resilience literature suggested new resilience properties—“risk-sensitivity”and“regenerative”in the timeline of two consecutive *** review highlights a causal pathway for social resilience to better understand the resilience status in a multi-shock scenario by depicting inherent and adaptive resilience for consecutive disaster scenarios and a historical case study for a resilience trajectory in a multiple disaster *** review findings will assist disaster management policymakers and practitioners to formulate appropriate resilience enhancement strategies within a holistic framework in a multi-disaster timeline.

关键词： Community resilience Disaster resilience Resilience assessment Resilience measurement Resilience properties

Observer-based Multirate Feedback Control Design for Two-time-scale system

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International Journal of Automation and computing 2021年第6期18卷 1007-1016页

作者： ravindra Munje Wei-Dong Zhang Department of Electrical Engineering K.K.Wagh Institute of Engineering Education and ResearchNashik 422003India Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China

The use of a lower sampling rate for designing a discrete-time state feedback-based controller fails to capture information of fast states in a two-time-scale system, while the use of a higher sampling rate increases the amount of computation considerably. Thus,the use of single-rate sampling for systems with slow and fast states has evident limitations. In this paper, multirate state feedback(MRsF) control for a linear time-invariant two-time-scale system is proposed. Here, multirate sampling refers to the sampling of slow and fast states at different sampling rates. Firstly, a block-triangular form of the original continuous two-time-scale system is constructed. Then, it is discretized with a smaller sampling period and feedback control is designed for the fast subsystem. Later, the system is block-diagonalized and equivalently represented into a system with a higher sampling period. subsequently, feedback control is designed for the slow subsystem and overall MRsF control is derived. It is proved that the derived MRsF control stabilizes the full-order system. Being the transformed states of the original system, slow and fast states need to be estimated for the MRsF control ***, a sequential two-stage observer is formulated to estimate these states. Finally, the applicability of the design method is demonstrated with a numerical example and simulation results are compared with the single-rate sampling method. It is found that the proposed MRsF control and observer designs reduce computations without compromising closed-loop performance.

关键词： Feedback control multirate sampling sequential observer two-stage design two-time-scale system

Bulk scale production of carbon nanofibers in an economical way

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Frontiers of Materials science 2012年第4期6卷 319-325页

作者： ravindra RAJARAO Badekai Ramachandra BHATI Catalysis and Materials Laboratory Department of ChemistryNational Institute of Technology KarnatakaSurathkalMangalore-575025India

An economical route for the scalable production of carbon nanofibers （CNFs） on a sodium chloride support has been developed. CNFs have been synthesized by chemical vapor deposition （CVD） method by using metal formate as catalyst precursors at 680℃. Products were characterized by sEM, TEM, Raman spectroscopy and XRD method. By thermal analysis, the purity of the as grown products and purified products were determined. This method avoids calcination and reduction process which was employed in commercial catalysts such as metal oxide or nitrate. The problems such as detrimental effect, environmental and even cost have been overcome by using sodium chloride as support. The yield of CNFs up to 7800 wt.% relative to the nickel catalyst has been achieved in the growth time of 15 min. The advantage of this synthesis technique is the simplicity and use of easily available low cost precursors.

关键词： metal formate carbon nanofiber (CNF) chemical vapor deposition (CVD),high yield sodium chloride support environmental friendly route

Edge preserving super-resolution algorithm using multi-stage cascaded joint bilateral filter

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International Journal of Modeling, simulation, and scientific Computing 2017年第1期8卷 37-51页

作者： Gunnam suryanarayana ravindra Dhuli school of Electronics Engineering VIT University Vellore-632014TamilnaduIndia

super-resolution(sR)algorithms address the inabilities of poor imaging devices,there by producing high quality images with enhanced *** propose a new sR approach which produces sharp high resolution(HR)image using its low resolution(LR)*** proposed method uses geometric duality for spatially adapting covariance-based interpolation(CBI).To preserve edge information,a multi-stage cascaded joint bilateral filter(MsCJBF)is proposed as an intermediary *** edges are incorporated in the high frequency subbands obtained by the stationary wavelet transform(sWT),through nearest neighbor interpolation(NNI)*** to the NNI process,the high frequency subbands undergo two-lobed lanczos interpolation to achieve the desired resolution *** quantitative and qualitative analysis for various test images prove the superiority of our method.

关键词： Joint bilateral filter image super-resolution covariance based interpolation stationary wavelet transform

static fluid spheres admitting Karmarkar condition

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Chinese Physics C 2020年第3期44卷 137-147页

作者： Ksh.Newton singh ravindra K.Bisht s.K.Maurya Neeraj Pant Department of Physics National Defence AcademyKhadakwaslaPune-411023India Department of Mathematics Jadavpur UniversityKolkata-700032India Department of Mathematics National Defence AcademyKhadakwaslaPune-411023India Department of Mathematical and Physical sciences College of Arts and ScienceUniversity of NizwaNizwaSultanate of Oman

We explore a new relativistic anisotropic solution of the Einstein field equations for compact stars based on embedding class one *** this purpose,we use the embedding class one methodology by employing the Karmarkar *** this methodology,we obtain a particular differential equation that connects both the gravitational potentials e^λ and e^ν.We solve this particular differential equation choosing a simple form of generalized gravitational potential grr to describe a complete structure of the space-time within the stellar *** determining this space-time geometry for the stellar models,we discuss thermodynamical observables including radial and tangential pressures,matter density,red-shift,velocity of sound,etc.,in the stellar *** also perform a complete graphical analysis,which shows that our models satisfy all the physical and mathematical requirements of ultra-high dense collapsed ***,we discuss the moment of inertia and M-R curve for rotating and non-rotating stars.

关键词： Karmarkar's condition exact solutions compact star general relativity

Magnetic ferrite/carbonized cotton fiber composites for improving electromagnetic absorption properties at gigahertz frequencies

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Journal of Materials science & Technology 2021年第27期86卷 127-138页

作者： sateesh Bandaru Narashima Murthy ravindra Kulkarni Niall J.English school of Chemical and Bioprocess Engineering University College DublinBelfieldDublin 4Ireland scinva Chemicals and Pharmaceuticals Pvt Ltd Kumbalagodu Industrial AreaBangaloreIndia BVDU’s Poona College of Pharmacy ErandawanePuneIndia

Ferrite/carbon composited materials,especially the bio-derived composited materials possessing both environmental friendliness and outstanding microwave absorption performance,attract numerous attentions for solving the"electromagnetic problem"in the Gigahertz frequency *** this work,we demonstrate a bio-derived ferrite/carbon material by compositing functional carbonized cotton fibers(CCFs)and Fe_(3)O_(4)nanoparticles with optimized microwave-absorption *** adjusting the carbonization conditions systematically,the Fe_(3)O_(4)loading contents and the microwave absorption properties can be varied simultaneously-and,indeed,optimized and *** CCFs-Fe_(3)O_(4)composites exhibited a minimum reflection-loss capacity RL(d B)of-56.8 d B at 10.9 GHz with a thickness of 1.67 mm,and its effective absorption bandwidth(RL(d B)s found to broaden to 7.1 *** characterizations,coupled with microstructure analyses,revealed that the enhancement in microwave absorption was triggered by the different microstructures of CCFs-Fe_(3)O_(4)composites-attributable to the different carbonization *** different conditions result in different amounts of Fe_(3)O_(4)attachment sites and lead to the enhancement of dielectric polarization at localized *** present work of bio-derived ferrite/carbon materials has important implications in understanding structure-performance relationships in dielectric-magnetic materials,and,meanwhile,could well be extended to a microwave-absorber design approach.

关键词： Electromagnetic absorption Bio-derived material Dielectric-magnetic composite Interfacial polarization