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Inverse modelling of aquifer parameters in basaltic rock with the help of pumping test method using MODFLOW software

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Geoscience Frontiers 2017年第6期8卷 1385-1395页

作者： Kanak Moharir Chaitanya Pande sanjay Patil Sant Gadge Baba Amravati University AmravatiIndia Maharashtra Remote Sensing Application Center PuneIndia

The origin and movement of groundwater are the fundamental questions that address both the temporal and spatial aspects of ground water run and water supply related issues in hydrological *** groundwater flows through an aquifer,its composition and temperature may variation dependent on the aquifer condition through which it ***,hydrologic investigations can also provide useful information about the subsurface geology of a *** because such studies investigate processes that follow under the Earth's shallow,obtaining the information necessary to answer these questions is not continuously ***,which discharge groundwater table directly,afford to study subsurface hydrogeological *** present study of estimation of aquifer factors such as transmissivity(T)and storativity(S)are vital for the evaluation of groundwater *** are several methods to estimate the accurate aquifer parameters(*** analysis,pumping test,etc.).In initial days,these parameters are projected either by means of in-situ test or execution test on aquifer well samples carried in the *** simultaneous information on the hydraulic behavior of the well(borehole)that provides on this method,the reservoir and the reservoir boundaries,are important for efficient aquifer and well data management and *** most common in-situ test is pumping test performed on wells,which involves the measurement of the fall and increase of groundwater level with respect to *** alteration in groundwater level(drawdown/recovery)is caused due to pumping of water from the ***(1935)was first to propose method to evaluate aquifer parameters from the pumping test on a bore well in a confined *** is essential to know the transmissivity(T=Kb,where b is the aquifer thickness;pumping flow rate,Q=TW(dh/dl)flow through an aquifer)and storativity(confined aquifer:S=bS_s,unconfined:S=S_y),for the characterization of the aquifer parameters in an unkn

关键词： Pumping test Hantush method GPS MODFLOW Inverse modelling Hydraulic parameters

Identification of ballast grading for rail track

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第5期9卷 945-954页

作者： Yifei Sun Chen Chen sanjay Nimbalkar Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering College of Civil and Transportation EngineeringHohai University School of Civil Miningand Environmental EngineeringUniversity of Wollongong School of Civil and Environmental Engineering University of Technology Sydney

Grading has long been recognised to critically influence the mechanical behaviour of *** identify the ballast grading for heavy-haul rail track,monotonic and cyclic triaxial tests are conducted to assess the performances of different *** deformations,aggregates degradation,resilience,shear resistance,maximum and minimum densities are recorded and *** grading is found to affect the behaviour of ballast in that coarser gradings exhibit relatively better strength,resilience and therefore less permanent ***,ballast degradation increases with the overall aggregate ***,to identify the grading for ballast with different performance objectives,a grey relational theory is used to convert the multi-objective into single-objective,*** relational grade.A relatively optimal grading that provides the highest grey relational grade is thus suggested for the improved ballast performance.

关键词： Ballast Deformation Grading Grey relational analysis

Cognitive Radios： A Survey On Spectrum Sensing, Security and Spectrum Handoff

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China Communications 2017年第11期14卷 185-208页

作者： Vishakha Ramani sanjay K.Sharma ECE Department University Institute of Technology Rajiv Gandhi Proudyogiki Vishwavidyalaya Ringgold Standard Institution Airport Bypass Road Bhopal Madhya Pradesh Bhopal Bhopal 462036 India

Pervasive wireless computing and communication have created an ever-increasing demand for more radio spectrum. Since, most of the spectrum is underutilized, it motivated the introduction of the concept of cognitive radios, a dynamic spectrum access enabling technology. The first stage of cognitive radio is to sense the environment and determine which parts of the spectrum are available. This is achieved through spectrum sensing. However, spectrum sensing poses the most fundamental challenge in cognitive radios. Moreover, cognitive radios suffer from many vulnerabilities and the security attacks can severely degrade the performance of cognitive radios. This paper surveys state-of-theart research on spectrum sensing and security threats in cognitive radios. Lastly, we also consider the analysis of issues related to spectrum handoffs in cognitive radios.

关键词： cogntive radio spectrum sesning security spectrum handoff

A Comparative Assessment of Temperature Data from Different Sources for Dehradun, Uttarakhand, India

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Journal of Meteorological Research 2016年第6期30卷 1019-1032页

作者： Atul Kant PIYOOSH sanjay Kumar GHOSH Department of Civil Engineering Indian Institute of Technology Roorkee

A comparative study of extreme temperature parameters from different sources is carried out by examining standardized anomalies, trends, correlation, and equivalence of datasets. Maximum temperature （Tmax） and minimum temperature （Wmln） for Dehradun, from two different sources such as computed and gridded data from Climatic Research Unit （CRU） and observed data from India Meteorological Department （IMD） are used for 1901-2012. The CRU data are compared initially with IMD, by graphical assessment of standardized anomalies. Subsequently, change points are identified by using Cumulative Sum （CUSUM）-chart technique for trend analysis. The magnitude and significance of trends are determined by applying Sen＇s slope test, and on the basis of these, trends are compared. Further, correlation analysis is carried out and datasets are tested for equivalence by using Wileoxon-Mann Whitney test. The result shows that annual standardized anomalies of CRU data follow the pattern of annual standardized anomalies of IMD data. The CRU data exhibit similar trends and are well correlated with IMD dataset. Moreover, CRU anomaly data are identical with IMD anomaly data in the recent decades. High resolution gridded CRU data have open access and may be more useful due to its spatio-temporal continuity for land areas of the world.

关键词： cumulative sum Sen's slope temperature trend temperature anomaly correlation Wilcoxon Mann-Whitney test

Secure and Optimal LOADng Routing for IoT with Composite RoutingMetric

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Computers, Materials & Continua 2023年第1期74卷 655-669页

作者： Divya Sharma sanjay Jain Vivek Maik Department of Electronics and Communication New Horizon College of EngineeringBengaluru560103India CMR Institute of Technology Bengaluru560037India Department of Electronics and Communication SRM Institute of Science and TechnologyKattankulathurChennai603203India

Security is the one of the major challenges for routing the data between the source and destination in an Internet of Things(IoT)*** overcome this challenge,a secure Lightweight On-demand Ad hoc Distancevector—Next Generation(LOADng)Routing Protocol is proposed in this *** the LOADng protocol is the second version of Ad Hoc On-Demand Distance Vector(AODV)protocol,it retains most of the basic functionality and characteristics of *** the route discovery process,the cyclic shift transposition algorithm(CSTA)is used to encrypt the control packets of the LOADng protocol to improve its *** approach only derives transposition and substitution without product cipher with respect to input *** this,for choosing the best probable path between the source and destination,routing metrics such as link quality Indicator(LQI),hop count(HC)and queue length(QL)are included in the control *** data is then securely sent using CSTA using the optimal secure path *** Results depict that the proposed secure and optimal LOADng(SO-LOADng)using CSTA encryption obtains better throughput,delivery ratio encryption time and decryption time than the existing state-ofart approaches.

关键词： IoT LOADng CSTA link quality indicator queue length

Order Bounded Weighted Composition Operators Mapping into the Dirichlet Type Spaces

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Chinese Annals of Mathematics,Series B 2016年第4期37卷 585-594页

作者： Yongxin GAO sanjay KUMAR Zehua ZHOU Department of Mathematics Tianjin UniversityTianjin 300072China. Department of Mathematics Central University of JammuINDIA. Center for Applied Mathematics Tianjin UniversityTianjin 300072China.

The authors characterize the order boundedness of weighted composition operators acting between Dirichlet type spaces.

关键词： Weighted composition operator Order boundedness Dirichlet typespaces Positive Borel measure

Liquefaction proneness of stratified sand-silt layers based on cyclic triaxial tests

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第7期15卷 1826-1845页

作者： Arpit Jain Satyendra Mittal sanjay Kumar Shukla Department of Civil Engineering Indian Institute of TechnologyRoorkeeUttarakhandIndia School of Engineering Edith Cowan UniversityJoondalupPerthAustralia Department of Civil Engineering Indian Institute of Technology MadrasChennaiIndia Department of Civil Engineering BIT SindriIndia

Most studies on liquefaction have addressed homogeneous soil strata using sand or sand with fine content without considering soil *** this study,cyclic triaxial tests were conducted on the stratified sand specimens embedded with the silt layers to investigate the liquefaction failures and void-redistribution at confining stress of 100 kPa under stress-controlled *** loosening of underlying sand mass and hindrance to pore-water flow caused localized bulging at the sand-silt *** is observed that at a silt thickness of 0.2H(H is the height of the specimen),nearly 187 load cycles were required to attain liquefaction,which was the highest among all the silt thicknesses with a single silt ***,0.2H is assumed as the optimum silt thickness(t_(opt)).The silt was placed at the top,middle and bottom of the specimen to understand the effect of silt layer *** to the increase in depth of the silt layer from the top position(capped soil state)to the bottom,the cycles to reach liquefaction(N_(cyc,L))increased 2.18 ***,when the number of silt layers increased from single to triple,there was an increase of about 880%in N_(cyc,L).The micro-characterization analysis of the soil specimens indicated silty materials transported in upper sections of the specimen due to the dissipated pore *** main parameters,including thickness(t),location(z),cyclic stress ratio(CSR),number of silt layers(n)and modified relative density(D_(r,m)),performed significantly in governing the lique-faction *** this,a multilinear regression model is developed based on critical parameters for prediction of N_(cyc,L).Furthermore,the developed constitutive model has been validated using the data from the present study and earlier findings.

关键词： Cyclic triaxial tests Soil stratification Soil liquefaction Regression model

Experimental study on repeatedly loaded foundation soil strengthened by wraparound geosynthetic reinforcement technique

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第4期13卷 899-911页

作者： Muhammad Nouman Amjad Raja sanjay Kumar Shukla Geotechnical and Geoenvironmental Engineering Research Group School of EngineeringEdith Cowan UniversityJoondalupPerthWA 6027Australia Department of Civil Engineering School of EngineeringUniversity of Management and TechnologyLahorePakistan Civil Engineering Department Delhi Technological UniversityDelhiIndia

In the recent past,the potential benefits of wraparound geosynthetic reinforcement technique for constructing the reinforced soil foundations have been *** paper presents the experimental study on the behaviour of model strip footing resting on sandy soil bed reinforced with geosynthetic in wraparound and planar forms under monotonic and repeated *** geosynthetic layers were laid according to the reinforcement ratio to minimise the scale *** is found that for the same amount of reinforcement material,the wraparound reinforced model resulted in less settlement in comparison to planar reinforced *** efficiency of wraparound reinforced model increased with the increase in load amplitude and the rate of total cumulative settlement substantially decreased with the increase in number of load *** wraparound reinforced model has shown about 45% lower average total settlement in comparison to unreinforced model,while the double-layer reinforced model has about 41% lower average total settlement at the cost of approximately twice the material and 1.5 times the occupied land width ***,wraparound models have shown much greater stability in comparison to their counterpart models when subjected to incremental repeated loading.

关键词： Geosynthetics Repeated loads Wraparound reinforcement technique Model tests Footing settlement Bearing capacity Reinforcement ratio Strip footing

Synthesis and Characterization of Bio-based Epoxy Blends from Renewable Resource Based Epoxidized Soybean Oil as Reactive Diluent

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Chinese Journal of Polymer Science 2015年第1期33卷 137-152页

作者： Sushanta K Sahoo Smita Mohanty sanjay K Nayak Laboratory for Advanced Research in Polymeric Materials (LARPM) Central Institute of Plastics Engineering & Technology (CIPET)B/25 CNI complex Patia Bhubaneswar 751024 Odisha India

A novel bioresin, epoxidized soybean oil was synthesized by in situ method and was characterized employing FTIR and NMR. The bioresin was blended with epoxy（DGEBA） at different ratios as reactive diluents for improved processibility and toughened nature. The composition with 20 wt% bioresin exhibited improved impact strength to the tune of 60% as compared to virgin epoxy. Fracture toughness parameters critical stress intensity factor（KIC） and critical strain energy release rate（GIC） were evaluated using single edge notch bending test and demonstrated superior enhancement in toughness. Dynamic mechanical, thermal, thermo mechanical and fracture morphological analyses have been studied for bio-based epoxy blends. Curing kinetics has been evaluated through DSC analysis to investigate the effect of bioresin on cross-linking reaction of neat epoxy with triethylenetetramine as curing agent.

关键词： Bio-based epoxy Soybean oil Fracture toughness Curing kinetics TMA.