检索结果-南通市图书馆

A Temporal Locality-Aware Page-Mapped Flash Translation Layer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2013年第6期28卷 1025-1044页

作者： Youngjae Kim Aayush gupta Bhuvan Urgaonkar National Center for Computational Sciences Oak Ridge National Laboratory IBM Almaden Research Center ACM IEEE Department of Computer Science and Engineering Pennsylvania State UniversityUniversity Park

The poor performance of random writes has been a cause of major concern which needs to be addressed to better utilize the potential of flash in enterprise-scale environments. We examine one of the important causes of this poor performance： the design of the flash translation layer （FTL） which performs the virtual-to-physical address translations and hides the erase-before-write characteristics of flash. We propose a complete paradigm shift in the design of the core FTL engine from the existing techniques with our Demand-Based Flash Translation Layer （DFTL） which selectively caches page- level address mappings. Our experimental evaluation using FlashSim with realistic enterprise-scale workloads endorses the utility of DFTL in enterprise-scale storage systems by demonstrating： 1） improved performance, 2） reduced garbage collection overhead and 3） better overload behavior compared with hybrid FTL schemes which are the most popular implementation methods. For example, a predominantly random-write dominant I/O trace from an OLTP application running at a large financial institution shows a 78% improvement in average response time （due to a 3-fold reduction in operations of the garbage collector）, compared with the hybrid FTL scheme. Even for the well-known read-dominant TPC-H benchmark, for which DFTL introduces additional overheads, we improve system response time by 56%. Moreover, interestingly, when write-back cache on DFTL-based SSD is enabled, DFTL even outperforms the page-based FTL scheme, improving their response time by 72% in Financial trace.

关键词： flash memory flash translation layer storage system

On certain new exact solutions of the Einstein equations for axisymmetric rotating fields

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2013年第10期22卷 73-78页

作者： Lakhveer Kaur R.K.gupta School of Mathematics and Computer Applications Thapar University

We investigate the Einstein field equations corresponding to the Weyl-Lewis-Papapetrou form for an axisymmetric rotating field by using the classical symmetry method. Using the invafiance group properties of the governing system of partial differential equations （PDEs） and admitting a Lie group of point transformations with commuting infinitesimal generators, we obtain exact solutions to the system of PDEs describing the Einstein field equations. Some appropriate canonical variables are characterized that transform the equations at hand to an equivalent system of ordinary differential equations and some physically important analytic solutions of field equations are constructed. Also, the class of axially symmetric solutions of Einstein field equations including the Papapetrou solution as a particular case has been found.

关键词： Einstein equations symmetry analysis exact solutions

Removal and recovery of toxic nanosized Cerium Oxide using eco-friendly Iron Oxide Nanoparticles

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2020年第1期14卷 175-184页

作者： Kanha gupta Nitin Khandelwal Gopala Krishna Darbha Department of Chemical Sciences USER KolkataMohanpurWest BengalPincode 741246India Environmental Nanoscience Laboratory Department of Earth SciencesUSER KolkataMohanpurWest BengalPincode 741246India Center for Climate&Environmental Studies USER KolkataMohanpurWest BengalPincode 741246India

Increasing applications of metal oxide nanoparticles and their release in the natural environment is a serious concern due to their toxic ***,it is essential to have eco-friendly solutions for the remediation of toxic metal oxides in an aqueous *** the present study,eco-friendly Iron Oxide Nanoparticles(IONPs)are synthesized using solvothermal technique and successfully characterized using scanning and transmission electron microscopy(SEM and TEM respectively)and powder X-Ray diffraction(PXRD).These IONPs were further utilized for the remediation of toxic metal oxide nanoparticle,i.e.,*** experiments were also performed in complex aqueous solutions and real water samples to check its applicability in the natural *** study was performed to show *** show that these 200 nm-sized spherical IONPs,as revealed by SEM and TEM analysis,were magnetite(Fe3O4)and contained short-range crystallinity as confirmed from XRD *** experiments show that the composite follows the pseudosecond-order kinetic *** k>0.99 for Langmuir sorption isotherm suggests chemisorption as probable removal mechanism with monolayer sorption of Ce02 NPs on *** than 80%recovery of adsorbed Ce02 NPs through ultrasonication and magnetic separation of reaction precipitate confirms reusability of *** removal%of Ce02 in various synthetic and real water samples was>90%signifying that IONPs are candidate adsorbent for the removal and recovery of toxic metal oxide nanoparticles from contaminated environmental water samples.

关键词： Adsorption toxic metal oxide remediation eco-friendly IONP Iron oxide CeO2 removal

Effect of defects on the electronic properties of WS_2 armchair nanoribbon

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Semiconductors 2015年第1期36卷 28-31页

作者： Bahniman Ghosh Aayush gupta Microelectronics Research Center 10100 Burnet Road Bldg. 160 University of Texas at Austin Austin TX 78758 USA Department of Electrical Engineering Indian Institute of Technology Kanpur Kanpur 208016 India

We have studied the WS2 armchair nanoribbon with various defects like vacancy, edge roughness, twist,turn and ripple and compared how the bandgap changes due to such defects with the bandgap of a nanoribbon with no defects. Materials like WS2 and other transition metal dichalcogenides（MX2） have a graphene like layered structure with hexagonal rings and have properties that have attracted a lot of interest. Hence it is essential to study the changes in the band structure of the nanoribbon of WS2 due to the inclusion of defects like vacancy, rough edge,wrap, ripple and twist for making any device based on WS2.

关键词： WS2 armchair nanoribbon electronic property

Complement pathway in Alzheimer’s pathology and retinal neurodegenerative disorders–the road ahead

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2020年第2期15卷 257-258页

作者： Mehdi Mirzaei Liting Deng Veer Bala gupta Stuart Graham vivek gupta Department of Molecular Sciences Macquarie UniversitySydneyNSWAustralia Australian Proteome Analysis Facility Macquarie UniversitySydneyNSWAustralia Department of Clinical Medicine Macquarie UniversitySydneyNSWAustralia School of Medicine Deakin UniversityGeelongVICAustralia

Chronic inflammation has increasingly been acknowledged as a hallmark feature of several progressive neurodegenerative disorders. Accruing evidence indicates that sustained inflammation compromises the core neuroprote... 详细信息

关键词： pathology neurodegenerative mechanisms

With newer tools for gene editing, is it time to revisit genetic therapy for cystic fibrosis?

在线全文

学校读者我要写书评

暂无评论

Genes & Diseases 2021年第2期8卷 168-180页

作者： Anuj gupta Ankita gupta Larissa Boyd Barts and the London School of Medicine and Dentistry Institution address-Garrod BuildingTurner StreetWhitechapelE12ADUnited Kingdom University of Birmingham Birmingham Medical schoolEdgbastonB152TTUnited Kingdom Barts and the London School of Medicine and Dentistry Garrod BuildingTurner StreetWhitechapelE12ADUnited Kingdom

Cystic Fibrosis(CF)is an autosomal recessive disease caused by mutations in the cystic fibrosis transmembrane conductance regulator(CFTR)gene on chromosome *** abnormalities affect the chloride channels in the mucus producing epithelial cells. With these channels not working properly,water is unable to leave the cells to enter the mucus;thus,leading to sticky mucus which obstructs airways and ducts in the body.

关键词： cystic airway properly

Prediction of COviD-19 Confirmed, Death, and Cured Cases in India Using Random Forest Model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Big Data Mining and Analytics 2021年第2期4卷 116-123页

作者： vishan Kumar gupta Avdhesh gupta Dinesh Kumar Anjali Sardana Department of Computer Science and Engineering(CSE) Graphic Era Deemed to be UniversityDehradun 248002India Department of CSE IMS Engineering CollegeGhaziabad 201009India Department of CSE KIET Group of InstitutionsGhaziabad 201206India

A novel coronavirus(SARS-CoV-2) is an unusual viral pneumonia in patients, first found in late December 2019, latter it declared a pandemic by World Health Organizations because of its fatal effects on public health. In this present, cases of COviD-19 pandemic are exponentially increasing day by day in the whole world. Here, we are detecting the COviD-19 cases, i.e., confirmed, death, and cured cases in India only. We are performing this analysis based on the cases occurring in different states of India in chronological dates. Our dataset contains multiple classes so we are performing multi-class classification. On this dataset, first, we performed data cleansing and feature selection, then performed forecasting of all classes using random forest, linear model, support vector machine,decision tree, and neural network, where random forest model outperformed the others, therefore, the random forest is used for prediction and analysis of all the results. The K-fold cross-validation is performed to measure the consistency of the model.

关键词： coronavirus COviD-19 respiratory tract multi-class classification random forest

Numerical modelling of pullout of helical soil nail

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2017年第4期9卷 648-658页

作者： Saurabh Rawat Ashok Kumar gupta Department of Civil Engineering Jaypee University of Information Technology Waknaghat Solan 173234 India

An investigation into the pullout response of helical soil nail using finite element subroutine Plaxis 2D is *** numerical modelling of actual pullout response is achieved by axisymmetric and horizontal loading *** effect of varying number of helical plates,helical plate spacing and helical plate diameter is studied to understand the pullout capacity *** failure surfaces for various helical soil nail configurations and their pullout mechanisms are also analysed and *** pullout capacity is found to increase with increase in number of helical *** helical plate spacing ratio（s/D;） and diameter ratio（D;/D;） are found to increase the pullout only up to a critical *** response of helical soil nail using axisymmetric finite element simulation is found similar to the uplift behaviour of helical piles and helical soil *** the absence of literature regarding numerical modelling of helical soil nail,simulation results are validated with uplift responses of helical piles and soil anchors.A good agreement in their comparative study for pullout response is also observed.

关键词： Finite element Helical soil nail Pullout response Plate spacing Plate diameter Failure mechanism

Test Case Prioritization in Unit and Integration Testing:A Shuffled-Frog-Leaping Approach

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2023年第3期74卷 5369-5387页

作者： Atulya gupta Rajendra Prasad Mahapatra Department of Computer Science and Engineering SRMISTDelhi-NCR CampusGhaziabad201204India

Both unit and integration testing are incredibly crucial for almost any software application because each of them operates a distinct process to examine the *** to resource constraints,when software is subjected to modifications,the drastic increase in the count of test cases forces the testers to opt for a test optimization *** such strategy is test case prioritization(TCP).Existing works have propounded various methodologies that re-order the system-level test cases intending to boost either the fault detection capabilities or the coverage efficacy at the ***,singularity in objective functions and the lack of dissimilitude among the re-ordered test sequences have degraded the cogency of their *** such gaps and scenarios when the meteoric and continuous updations in the software make the intensive unit and integration testing process more fragile,this study has introduced a memetics-inspired methodology for *** proposed structure is first embedded with diverse parameters,and then traditional steps of the shuffled-frog-leaping approach(SFLA)are followed to prioritize the test cases at unit and integration *** 5 standard test functions,a comparative analysis is conducted between the established algorithms and the proposed approach,where the latter enhances the coverage rate and fault detection of re-ordered test *** results related to the mean average percentage of fault detection(APFD)confirmed that the proposed approach exceeds the memetic,basic multi-walk,PSO,and optimized multi-walk by 21.7%,13.99%,12.24%,and 11.51%,respectively.

关键词： Test case prioritization unit testing shuffled frog leaping approach memetic based optimization algorithm integration testing