检索结果-南通市图书馆

Glacier area change (1993-2019) and its relationship to debris cover, proglacial lakes, and morphological parameters in the Chandra-Bhaga Basin, Western Himalaya, India

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 Mountain Science 2024年第4期21卷 1287-1306页

作者： VATSAL Sarvagya AZAM Mohd Farooq BHARDWAJ Anshuman MANDAL Arindan BAHUGUNA Ishmohan RAMANATHAN Alagappan RAJU N.Janardhana tomar Sangita Singh Department of Civil Engineering Indian Institute of Technology IndoreSimrol 453552India School of Geosciences University of AberdeenKing’s CollegeAberdeen AB243FXUnited Kingdom Interdisciplinary Centre for Water Research Indian Institute of ScienceBengaluru 560012India Space Application Centre Ahmedabad 380015India School of Environmental Sciences Jawaharlal Nehru UniversityNew Delhi 110067India Department of Geography Norwegian University of Science and TechnologyTrondheim No-7491Norway

Glacier inventories serve as critical baseline data for understanding the impacts of climate change on glaciers.The present study maps the outlines of glaciers in the Chandra-Bhaga Basin(western Himalaya)for the years 1993,2000,2010,and 2019 using Landsat Thematic Mapper(TM),Enhanced Thematic Mapper(ETM),and Operational Land Imager(OLI)datasets.A total of 251 glaciers,each having an area above 0.5 km^(2),were identified,which include 216 clean-ice and 35 debris-covered glaciers.Area changes are estimated for three periods:1993-2000,2000-2010,and 2010-2019.The total glacierized area was 996±62 km^(2) in 1993,which decreased to 973±70 km^(2) in 2019.The mean rate of glacier area loss was higher in the recent decade(2010-2019),at 0.036 km^(2),compared to previous decades(0.029 km^(2) in 2000-2010 and 0.025 km^(2) in 1993-2000).Supraglacial debris cover changes are also mapped over the period of 1993 and 2019.It is found that the supraglacial debris cover increased by 14.12±2.54 km^(2)(15.2%)during 1993-2019.Extensive field surveys on Chhota Shigri,Panchi II,Patsio,Hamtah,Mulkila,and Yoche Lungpa glaciers were carried out to validate the glacier outlines and supraglacial debris cover estimated using satellite datasets.Controls of various morphological parameters on retreat were also analyzed.It is observed that small,clean ice,south oriented glaciers,and glaciers with proglacial lakes are losing area at faster rates than other glaciers in the basin.

关键词： Glacier Area change Debris cover Morphology Proglacial lake

Enhanced Heat Transfer Technology Based on Emission Reduction and Carbon Reduction in Cutting and Grinding

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2023年第4期36卷 1-3页

作者： Changhe Li Yanbin Zhang shubham Sharma School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China Department of Mechanical Engineering and Advanced Materials Science Regional Center for Extension and DevelopmentCouncil of Scientific and Industrial Research(CSIR)-Central Leather Research Institute(CLRI)Jalandhar 144021India

Huge carbon emissions in machining process,which characterized by high energy consumption and usage of non-renewable resources,is becoming an obsession in the past decades.In the face of the international strategy of carbon peak,it is imperative to eliminate the usage of mineral cutting fluids and reduce energy consumption and carbon emissions by green cutting/grinding technologies,such as dry cutting,minimum quantity lubrication(MQL).

关键词： grinding lubrication eliminate

Hardware Chip Performance of CORDIC Based OFDM Transceiver for Wireless Communication

在线全文

学校读者我要写书评

暂无评论

Computer Systems Science & Engineering 2022年第2期40卷 645-659页

作者： Amit Kumar Adesh Kumar Geetam Singh tomar Faculty of Technology Uttarakhand Technical UniversityDehradun248007India Department of Electrical&Electronics Engineering School of EngineeringUniversity of Petroleum and Energy StudiesDehradun248007India Birla Institute of Applied Sciences Nainital263136India

The fourth-generation(4G)and fifth-generation(5G)wireless communication systems use the orthogonal frequency division multiplexing(OFDM)modulation techniques and subcarrier allocations.The OFDM modulator and demodulator have inverse fast Fourier transform(IFFT)and fast Fourier transform(FFT)respectively.The biggest challenge in IFFT/FFT processor is the computation of imaginary and real values.CORDIC has been proved one of the best rotation algorithms for logarithmic,trigonometric,and complex calculations.The proposed work focuses on the OFDM transceiver hardware chip implementation,in which 8-point to 1024-point IFFT and FFT are used to compute the operations in transmitter and receiver respectively.The coordinate rotation digital computer(CORDIC)algorithm has read-only memory(ROM)-based architecture to store FFT twiddle factors and their angle generators.The address generation unit is required to fetch the data and write the results into the memory in the appropriate sequence.CORDIC provides low memory,delay,and optimized hardware on the field-programmable gate array(FPGA)in comparison to normal FFT architecture for the OFDM system.The comparative performance of the FFT and CORDICFFT based OFDM transceiver chip is estimated using FPGA parameters:slices,flip-flops,lookup table(LUTs),frequency,power,and delay.The design is developed using integrated synthesis environment(ISE)Xilinx version 14.7 software,synthesized using very-high-speed integrated circuit hardware description language(VHDL),and tested on Virtex-5 FPGA.

关键词： 5G Communication CORDIC Algorithm FFT Virtex-5 FPGA OFDM Communication

Real Time Control System for Metro Railways Using PLC & SCADA

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Intelligent Automation & Soft Computing 2023年第2期35卷 1403-1421页

作者： Ishu tomar Indu Sreedevi Neeta Pandey Department of Electronics and Communication Engineering Delhi Technological UniversityDelhi110042India

This paper proposes to adopt SCADA and PLC technology for the improvement of the performance of real time signaling&train control systems in metro railways.The main concern of this paper is to minimize the failure in automated metro railways system operator and integrate the information coming from Operational Control Centre(OCC),traction SCADA system,traction power control,and power supply system.This work presents a simulated prototype of an automated metro train system operator that uses PLC and SCADA for the real time monitoring and control of the metro railway systems.Here,SCADA is used for the visualization of an automated process operation and then the whole opera-tion is regulated with the help of PLC.The PLC used in this process is OMRON(NX1P2-9024DT1)and OMRON’s Sysmac studio programming software is used for developing the ladder logic of PLC.The metro railways system has deployed infrastructure based on SCADA from the power supply system,and each station’s traction power control is connected to the OCC remotely which commands all of the stations and has the highest command priority.An alarm is triggered in the event of an emergency or system congestion.This proposed system overcomes the drawbacks of the current centralized automatic train control(CATC)system.This system provides prominent beneﬁts like augmenting services which may enhance a network’s full load capacity and networkﬂexibility,which help in easy modiﬁcation in the existing program at any time.

关键词： Train control system automation PLC(programmable logic controller) SCADA(supervisory control and data acquisition)

Real Time Automation and Ratio Control Using PLC&SCADA in Industry 4.0

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Systems Science & Engineering 2023年第5期45卷 1495-1516页

作者： Basant tomar Narendra Kumar Mini Sreejeth Dept of Electrical Engineering Delhi Technological UniversityDelhi 110042India

Industrial Control Systems(ICS)and SCADA(Supervisory Control and Data Acquisition)systems play a critical role in the management and regulation of critical infrastructure.SCADA systems brings us closer to the real-time application world.All process and equipment control capability is typically provided by a Distributed Control System(DCS)in industries such as power stations,agricultural systems,chemical and water treatment plants.Instead of control through DCS,this paper proposes a SCADA and PLC(Programmable Logic Controller)system to control the ratio control division and the assembly line division inside the chemical plant.A specific design and implementation method for development of SCADA/PLC based real time ratio control and automated assembly line system in a chemical plant is introduced.The assembly line division is further divided into sorting stage,filling stage and the auxiliary stage,which includes the capping unit,labelling unit and then the storage.In the ratio control division,we have defined the levels inside the mixer and ratio of the raw materials through human machine interface(HMI)panel.The ratio of raw materials is kept constant on the basis of flow rates of wild stream and manipulated stream.There is a flexibility in defining new levels and the ratios of the raw materials inside the mixer.But here we taken the predefined levels(low,medium,high)and ratios(3:4,2:1,2:5).Control valves are used for regulating the flow of the compositions.In the assembly line division,the containers are sorted on the basis of size and type of material used i.e.,big sized metallic containers and small sized non-metallic containers by inductive and capacitive proximity sensors.All the processes are facilitated with laser beam type or reflective type sensors on the conveyor system.Building a highly stable and dependable PLC/SCADA system instead of Distributed Control System is required to achieve automatic management and control of chemical industry processes to reduce waste manpower and physical resources,as well as

关键词： Industry 4.0 ratio control automation PLC SCADA control valves proximity sensors conveyor system solenoid valves

Abundant analytical soliton solutions and different wave profiles to the Kudryashov-Sinelshchikov equation in mathematical physics

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 Ocean Engineering and Science 2022年第6期7卷 565-577页

作者： Sachin Kumar Monika Niwas shubham Kumar Dhiman Department of Mathematics Faculty of Mathematical SciencesUniversity of DelhiDelhi 110007India

The generalized exponential rational function(GERF)method is used in this work to obtain analytic wave solutions to the Kudryashov-Sinelshchikov(K S)equation.The K S equation depicts the occurrence of pressure waves in mixtures of liquid-gas bubbles while accounting for thermal expansion and viscosity.By applying the GERF method to the KS equation,we obtain analytic solutions in terms of trigonometric,hyperbolic,and exponential functions,among others.These solutions include solitary wave solutions,dark-bright soliton solutions,singular soliton solutions,singular bell-shaped solutions,traveling wave solutions,rational form solutions,and periodic wave solutions.We discuss the two-dimensional and three-dimensional graphics of some obtained solutions under the accurate range space by selecting appropriate values for the involved arbitrary parameters to make this research more praiseworthy.The obtained analytic wave solutions specify the GERF method’s dependability,capability,trustworthiness,and efficiency.

关键词： Solitary wave solutions Closed form solutions GERF technique Dynamical wave structures

Multiple Elite Individual Guided Piecewise Search-Based Differential Evolution

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2023年第1期10卷 135-158页

作者： shubham Gupta Shitu Singh Rong Su Shangce Gao Jagdish Chand Bansal the School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore the Department of Mathematics South Asian UniversityNew Delhi 110021India IEEE Faculty of Engineering University of ToyamaToyama-shi 930-8555Japan

The differential evolution(DE)algorithm relies mainly on mutation strategy and control parameters'selection.To take full advantage of top elite individuals in terms of fitness and success rates,a new mutation operator is proposed.The control parameters such as scale factor and crossover rate are tuned based on their success rates recorded over past evolutionary stages.The proposed DE variant,MIDE,performs the evolution in a piecewise manner,i.e.,after every predefined evolutionary stages,MIDE adjusts its settings to enrich its diversity skills.The performance of the MIDE is validated on two different sets of benchmarks:CEC 2014 and CEC 2017(special sessions&competitions on real-parameter single objective optimization)using different performance measures.In the end,MIDE is also applied to solve constrained engineering problems.The efficiency and effectiveness of the MIDE are further confirmed by a set of experiments.

关键词： Control parameters differential Evolution metaheuristic algorithms mutation operator

Click chemistry and drug delivery:A bird's-eye view

在线全文

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2023年第5期13卷 1990-2016页

作者： Shameer M.Kondengadan shubham Bansal Ce Yang Dongning Liu Zach Fultz Binghe Wang Department of Chemistry and Center for Diagnostics and Therapeutics Georgia State UniversityAtlantaGA 30303USA

Click chemistry has been proven to be very useful in drug delivery.Due to the availability of a large number of click reactions with a various characteristics,selection of appropriate chemistry for a given application is often not a trivial task.This review is written for pharmaceutical researchers who are interested in click chemistry applications and yet may not be click chemistry experts.For this,the review gives an overview of available click reactions organized by application types.Further,the general understanding of click reactions being fast and high yielding sometimes overshadows the need to analyze reaction kinetics in assessing suitability of a given reaction for certain applications.For this,we highlight the need to analyze the relationship among reaction kinetics,concentration effects,and reaction time scales,knowing that lack of such analysis could easily lead to failures.Further,possible issues such as chemical stability with various click reagents are also discussed to aid experimental designs.Recent examples and extensive references are also provided to aid in-depth understanding of technical details.We hope this review will help those interested in using click chemistry in drug delivery to select the appropriate reactions/reagents and minimize the number of pitfalls.

关键词： Bioorthogonal chemistry Bond-breaking reaction PROTAC Antibody—drug conjugates Gasotransmitters

Tribological Performance of Different Concentrations of Al_(2)O_(3)Nanofluids on Minimum Quantity Lubrication Milling

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2023年第4期36卷 67-78页

作者： Xiufang Bai Juan Jiang Changhe Li Lan Dong Hafiz Muhammad Ali shubham Sharma School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China School of Mechanical and Electrical Engineering Qingdao Binhai UniversityQingdao 266555China Mechanical Engineering Department King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Department of Mechanical Engineering IK Gujral Punjab Technical UniversityMain Campus-KapurthalaJalandhar 144603India

Nanofluid minimum quantity lubrication(NMQL)is a green processing technology.Cottonseed oil is suitable as base oil because of excellent lubrication performance,low freezing temperature,and high yield.Al_(2)O_(3)nanoparticles improve not only the heat transfer capacity but also the lubrication performance.The physical and chemical proper-ties of nanofluid change when Al_(2)O_(3)nanoparticles are added.However,the effects of the concentration of nanofluid on lubrication performance remain unknown.Furthermore,the mechanisms of interaction between Al_(2)O_(3)nanoparti-cles and cottonseed oil are unclear.In this research,nanofluid is prepared by adding different mass concentrations of Al_(2)O_(3)nanoparticles(0,0.2%,0.5%,1%,1.5%,and 2%wt)to cottonseed oil during minimum quantity lubrication(MQL)milling 45 steel.The tribological properties of nanofluid with different concentrations at the tool/workpiece interface are studied through macro-evaluation parameters(milling force,specific energy)and micro-evaluation parameters(surface roughness,micro morphology,contact angle).The result show that the specific energy is at the minimum(114 J/mm^(3)),and the roughness value is the lowest(1.63μm)when the concentration is 0.5 wt%.The surfaces of the chip and workpiece are the smoothest,and the contact angle is the lowest,indicating that the tribological proper-ties are the best under 0.5 wt%.This research investigates the intercoupling mechanisms of Al_(2)O_(3)nanoparticles and cottonseed base oil,and acquires the optimal Al_(2)O_(3)nanofluid concentration to receive satisfactory tribological properties.

关键词： Milling Al_(2)O_(3)nanofluid Minimum quantity lubrication(MQL) Surface micromorphology