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A spatio-temporal assessment and prediction of Ahmedabad's urban growth between 1990–2030

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Journal of Geographical Sciences 2022年第9期32卷 1791-1812页

作者： shobhit chaturvedi Kunjan SHUKLA Elangovan RAJASEKAR Naimish BHATT Department of Architecture and Planning Indian Institute of TechnologyRoorkee247667India Department of Civil Engineering School of TechnologyPandit Deendayal Petroleum UniversityGandhinagar382007India

Analyzing long term urban growth trends can provide valuable insights into a city’s future *** study employs LANDSAT satellite images from 1990,2000,2010 and 2019 to perform a spatiotemporal assessment and predict Ahmedabad’s urban *** Use Land Change(LULC)maps developed using the Maximum Likelihood classifier produce four principal classes:Built-up,Vegetation,Water body,and“Others”.In between 1990-2019,the total built-up area expanded by 130%,132 km^(2) in 1990 to 305 km^(2) in *** population growth is the chief contributor towards urban growth as the city added 3.9 km^(2) of additional built-up area to accommodate every 100,000 new ***,a Multi-Layer Perceptron-Markov Chain model(MLP-MC)predicts Ahmedabad’s urban expansion by *** to 2019,the MLP-MC model predicts a 25%and 19%increase in Ahmedabad’s total urban area and population by ***,these trends shall generate many socio-economic and environmental ***,future urban development policies must balance further development and environmental damage.

关键词： land use land cover urbanization maximum likelihood classification multi-layer perceptron–Markov chain model

Numerical investigation of dynamic interaction with projectile and harmonic behaviour for T-finned machine gun barrels

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Defence Technology（防务技术） 2020年第2期16卷 460-469页

作者： Ekansh chaturvedi Maulana Azad National Institute of Technology Bhopal 462003India

Machine gun barrels differ from their rifle counterparts in terms of *** support high rates of sustained fire,machine gun barrels are made thicker in order to dissipate more heat and maintain their flexural rigidity and thus accuracy,but on other hand they also contribute in weight addition to *** investigation deals with comparison between a conventional machine gun barrel and an improved innovative design having T-fins,both having same weight and chambered in 5.56×45 NATO ammunition,to compare their structural and harmonic characteristics which were parameterized by factors such as modal spectrum,directional deformation at muzzle ends during a single shot fire and harmonic behaviour at corresponding range of exciting *** solid models of both the barrels having same weight,were created using *** continuous input data functions were generated by MATLAB using the field tested discreet data *** generated velocity-distance functions were converted into time dependent functions using integration algorithms to calculate transient parameters such as time steps,excitation frequency range,angle of rotation of projectile and its angular *** dynamic condition simulated the varying nature of forces due to eccentricity in projectile and this data was fed to a time step study using ANSYS transient structural work bench followed by modal and harmonic *** results showed a significant reduction in muzzle end deformation which thus proved that the T-finned barrel,although had same weight as that of the conventional one,but had better structural and harmonic characteristics,and hence it would inherit better firing accuracy.

关键词： FSHP Machine guns Pseudo-I section Second order mesh Transient behaviour

ESTIMATION OF A SUBSET OF REGRESSION COEFFICIENTS OF INTEREST IN A MODEL WITH NON-SPHERICAL DISTURBANCES

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Journal of Systems Science & Complexity 2013年第2期26卷 209-231页

作者： chaturvedi Anoop KESARWANI Suchita Department of Statistics University of Allahabad

This paper considers the estimation of a subset of regression coefficients in a linear regression model with non-spherical disturbances,when other regression coefficients are of no interest.A family of estimators is considered and its asymptotic distribution is *** proposed family of improved estimators is compared with the usual unrestricted FGLS estimator,and dominance conditions are obtained with respect to risk under quadratic loss as well as the Pitman nearness *** results of a numerical simulation are presented to illustrate the risk performance of various estimators.

关键词： Large sample asymptotic minimum mean square error non-spherical disturbances pitman nearness criterion quadratic loss risk.

A comprehensive review of the effect of different kinetic promoters on methane hydrate formation

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Chinese Journal of Chemical Engineering 2021年第4期34卷 1-16页

作者： Ekta chaturvedi Sukumar Laik Ajay Mandal Gas Hydrates Laboratory Petroleum Engineering DepartmentIndian Institute of Technology(ISM)DhanbadIndia

Gas hydrates have recently emerged as a better alternative for the production,storage,and transportation of natural ***,factors like slow formation rate and limited storage capacity obstruct the possible industrial application of this *** types of promoters and synergists have been developed that can improve the kinetics and storage capacity of gas *** review focuses on different kinetic promoters and synergists that can be utilized to enhance the storage capacity of *** main characteristics,structure and the possible limitations of the use of these promoters are likewise portrayed in *** relationship between structure and storage capacity of hydrates have also been discussed in the *** status of production of gas from hydrates,their restrictions,and future difficulties have additionally been addressed in the ensuing areas of the review.

关键词： Gas hydrates Structure Storage capacity Kinetic promoters Nano-materials Surfactants

Computer aided design and analysis of a tunable muzzle brake

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Defence Technology（防务技术） 2019年第1期15卷 89-94页

作者： Ekansh chaturvedi Ravi K.Dwivedi Department of Mechanical Engineering Maulana Azad National Institute of Technology

This research work deals with the design of a tunable muzzle brake [10] for a rifle chambered in 5.56 x 45 NATO ammunition. It proposes to solve the problem of handling differences from shooter to shooter by incorporating the feature of tunability. Beside this, it also solves the problem of requirement of optimum recoil in short recoil weapons. This innovation gives this design an edge over its already existing counterparts in the market. The product is designed using the internal ballistics calculations and the investigations been performed using solidworks flow simulation tool and ANSYS static structural to check the parameters like velocity distribution, pressure growth, and muzzle brake force along the series of ports and comparison of the so found results with those devised by the authors of the documents mentioned in references. This assures the market adaptability of the product for satisfactory performance, when brought among its already existing counterpart, though with a slight edge over them due to tunability. The results so found shall be concluded satisfactory regarding the performance of muzzle brake.

关键词： Flow simulation Innovation Muzzle brake Tunability Set screws

Study of synthetic aperture radar and automatic identification system for ship target detection

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Journal of Ocean Engineering and Science 2019年第2期4卷 173-182页

作者： Sudhir Kumar chaturvedi Department of Aerospace Engineering University of Petroleum&Energy StudiesDehradun 248007India

In the past,the main goals of Synthetic Aperture Radar(SAR)systems were the study of the interaction of electromagnetic waves with the earth ***,the development of multi-channel SAR systems has enabled the development of more sophisticated techniques for the surveillance *** is the most efficient instrument,which provides high-resolution data for wide ocean area surveillance under all weather *** intrinsic capability of this instrument is to provide a quick view of the oceanic surface features such as vessels,waves and currents,oil spills,laver facilities and wind *** ship detection or recognition is achieved in two steps:the first step is to identify the target in SAR images of a busy traffic,which corresponds to Automatic Identification System(AIS)signals by the“dead-reckoning(DR)position”,and the second step is to estimate the position,size and speed of the ship from SAR images and compare these results with the AIS“true”*** paper presents the fundamentals of SAR and its integration with the AIS data for the ship target detection.

关键词： SAR AIS Dead reckoning Target detection.

Comparative analysis of spray-drying microencapsulation of Lacticaseibacillus casei in synbiotic legume-based beverages

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Food Bioscience 2022年第6期50卷 1605-1614页

作者： Smriti chaturvedi Snehasis Chakraborty Department of Food Engineering and Technology Institute of Chemical TechnologyMumbai400019India

This study investigated the effect of three carrier agents, viz. maltodextrin (MD), gum acacia (GA), and xanthan gum (XG), on three synbiotic legume-based beverages subjected to optimized spray-drying conditions. Several characteristics of the encapsulated synbiotic powders were evaluated, including moisture content, bulk, and tapped density, dissolution encapsulation efficiency, flow properties, particle density, porosity, color, and powder yield. The survivability of probiotic bacteria Lacticaseibacillus casei ATCC 335 was also observed under gastric acid, bile salts, and simulated gastrointestinal tract. The results showed that while the higher powder yield (11–23%) was shown by MD-coated beverage powders, GA-coated beverage powders showed better encapsulation efficiency (79.9–89.3%) as well as lower moisture content values (7 log CFU/mL) in the case of gastrointestinal simulation and under gastric acid and bile juice. The scanning electron microscopy also showed the desirable particle morphology and formation of microcapsules preserving the probiotic activity. The thermal properties of GA-coated KB powder showed the peak degradation temperature as 143.44 °C, which suggested the use of appropriate drying temperatures for making stable encapsulated synbiotic powders. Thus, GA-coated KB powder holds the potential to be used as a functional food with synbiotic properties along with acceptable powder characteristics and maximum probiotic survivability.

关键词： Carrier agents In-vitro gastrointestinal digestion Probiotic Non-dairy Prebiotics

Soil-Plant-Microbe Interactions in Stressed Agriculture Management:A Review

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Pedosphere 2017年第2期27卷 177-192页

作者： shobhit Raj VIMAL Jay Shankar SINGH Naveen Kumar ARORA Surendra SINGH Department of Environmental Microbiology Babashaeb Bhimrao Ambedkar (Central) University Lucknow 226025 (India) Department of Botany Banaras Hindu University Varanasi 221005 (India)

The expected rise in temperature and decreased precipitation owing to climate change and unabated anthropogenic activities add complexity and uncertainty to agro-industry. The impact of soil nutrient imbalance, mismanaged use of chemicals, high temperature, flood or drought, soil salinity, and heavy metal pollutions, with regard to food security, is increasingly being explored worldwide. This review describes the role of soil-plant-microbe interactions along with organic manure in solving stressed agriculture problems. Beneficial microbes associated with plants are known to stimulate plant growth and enhance plant resistance to biotic （diseases） and abiotic （salinity, drought, pollutions, etc.） stresses. The plant growth-promoting rhizobemteria （PGPR） and mycorrhizae, a key component of soil microbiota, could play vital roles in the maintenance of plant fitness and soil health under stressed environments. The application of organic manure as a soil conditioner to stressed soils along with suitable microbial strains could further enhance the plant-microbe associations and increase the crop yield. A combination of plant, stress-tolerant microbe, and organic amendment represents the tripartite association to offer a favourable environment to the proliferation of beneficial rhizosphere microbes that in turn enhance the plant growth performance in disturbed agro-ecosystem. Agriculture land use patterns with the proper exploitation of plant-microbe associations, with compatible beneficial microbial agents, could be one of the most effective strategies in the management of the concerned agriculture lands owing to climate change resilience. However, the association of such microbes with plants for stressed agriculture management still needs to be explored in greater depth.

关键词： beneficial microbes fungi microbial agents rnycorrhiza organic manure pathogen plant health plant growth-promoting rhizobacteria

Mathematical modelling and analysis of plastic waste pollution and its impact on the ocean surface

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Journal of Ocean Engineering and Science 2020年第2期5卷 136-163页

作者： Sonam chaturvedi Bikarama Prasad Yadav Nihal Anwar Siddiqui Sudhir Kumar chaturvedi Department of Health Safety Environment and Civil Engineering University of Petroleum and Energy Studies(UPES)Bidholi Energy AcresDehradun 248007India Department of Aerospace Engineering University of Petroleum and Energy Studies(UPES)Bidholi Energy AcresDehradun 248007India

Plastic contamination is universal all through the marine condition,yet gauges of the worldwide plenitude and weight of coasting plastics have needed information,especially from the Southern Hemisphere and remote *** we report a gauge of the all-out number of plastic particles and their weight gliding on the planet’s seas from 24 endeavours(2007-2013)over every one of the five subtropical gyres,coastal Australia,Bay of Bengal and the Mediterranean Sea directing surface net tows(N=680)and visual review transects of huge plastic flotsam and debris(N=891).Utilizing an oceanographic model of coasting trash dispersal adjusted by our information,and rectifying for wind-driven vertical blending,we gauge at least 5.25 trillion particles weighing 268,940 *** looking at between four size classes,two micro plastic4.75 mm,a huge loss of micro plastics is seen from the ocean surface contrasted with anticipated paces of discontinuity,recommending there are systems at play that expel<4.75 mm plastic particles from the sea *** focus on the life cycle assessment and the brief overview of the plastic waste management over the ocean surfaces with the various mathematical models has been *** impact of the ocean pollution is also being analysed.

关键词： Solid waste Plastic Garbage patch Ocean pollution Mathematical model Ocean surface