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Predicting upslope expansion of sub-alpine forest in the Makalu Barun National Park, Eastern Nepal, with a hybrid cartographic model

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Journal of Forestry Research 2018年第1期29卷 129-137页

作者： parveen Kumar Chhetri Department of Geography Texas A&M UniversityCollege Station

The natural upper boundary of a forest（forest line） in mountain environments is an indicator of climate conditions. An increase in global average temperatures has resulted in an upward advance of the forest line. This advance may result in fragmentation of the alpine ecosystem and a loss of biodiversity. Therefore, it is important to identify potential areas where current forests can advance under scenarios of future climate change. I used expert knowledge and cartographic modeling to create a hybrid cartographic model considering five topographic variables to predict areas where forest line can expand in the *** prediction accuracy of the model is around 82%. The model is able to predict areas above the current forest line that are suitable or unsuitable for future forest *** inclusion of high-resolution satellite imagery and digital elevation models, as well as field-based information into the model can help to improve the model accuracy.

关键词： Climate change Forest line Forest line advance Hybrid cartographic model Makalu Barun National Park

Newly Design Porous/Sponge Red Phosphorus@Graphene and Highly Conductive Ni2P Electrode for Asymmetric Solid State Supercapacitive Device With Excellent Performance

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Nano-Micro Letters 2020年第2期12卷 169-184页

作者： Nazish parveen Muhammad Hilal Jeong In Han Department of Chemistry College of ScienceKing Faisal UniversityAl‑Ahsa 31982Saudi Arabia Flexible Display and Printed Electronic Lab Department of Chemical and Biochemical EngineeringDongguk University-SeoulSeoul 04620Republic of Korea

Supercapacitors have attracted much attention in the field of electrochemical energy ***,material preparation,stability,performance as well as power density limit their applications in many ***,a sponge-like red phosphorus@graphene(rP@rGO)negative electrode and a Ni2P positive electrode were prepared using a simple one-step *** electrodes showed excellent performances(294 F g^−1 and 1526.6 F g^−1 for rP@rGO and Ni2P,respectively),which seem to be the highest among all rP@rGO-and Ni2P-based electrodes reported so *** asymmetric solid-state supercapacitor was assembled by sandwiching a gel electrolyte-soaked cellulose paper between rP@rGO and Ni2P as the negative and positive *** to other asymmetric devices,the device,which attained a high operating window of up to 1.6 V,showed high energy and power density values of 41.66 and 1200 W kg−1,*** also has an excellent cyclic stability up to 88%after various consecutive charge/discharge ***,the device could power commercial light emitting diodes and fans for 30 ***,the ease of the synthesis method and excellent performance of the prepared electrode materials mat have significant potential for energy storage applications.

关键词： Sponge red phosphorus Porous graphene Ni2P Electrode Asymmetric solid-state supercapacitor

Exact solutions for the flow of second grade fluid in annulus between torsionally oscillating cylinders

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Acta Mechanica Sinica 2011年第2期27卷 222-227页

作者： Amir Mahmood Saima parveen Najeeb Alam Khan Department of Mathematics COMSATS Institute of Information Technology Lahore Pakistan Abdus Salam School of Mathematical Sciences Lahore Pakistan Department of Mathematics University of Karachi Karachi-75270 Pakistan

The velocity field and the associated shear stress corresponding to the torsional oscillatory flow of a second grade fluid, between two infinite coaxial circular cylinders, are determined by means of the Laplace and Hankel transforms. At time t = 0, the fluid and both the cylinders are at rest and at t = 0 ＋ , cylinders suddenly begin to oscillate around their common axis in a simple harmonic way having angular frequencies ω 1 and ω 2 . The obtained solutions satisfy the governing differential equation and all imposed initial and boundary conditions. The solutions for the motion between the cylinders, when one of them is at rest, can be obtained from our general solutions. Furthermore, the corresponding solutions for Newtonian fluid are also obtained as limiting cases of our general solutions.

关键词： Second grade fluid · Velocity field · Shear stress · Longitudinal oscillatory flow · Laplace and Hankel transforms

Adenyl cyclase activator forskolin protects against Huntington's disease-like neurodegenerative disorders

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Neural Regeneration Research 2017年第2期12卷 290-300页

作者： Sidharth Mehan Shaba parveen Sanjeev Kalra Department of Pharamcology Rajendra Institute of Technology & Sciences Sirsa Haryana India

Long term suppression of succinate dehydrogenase by selective inhibitor 3-nitropropionic acid has been used in rodents to model Huntington＇s disease where mitochondrial dysfunction and oxidative damages are primary pathological hallmarks for neuronal damage. Improvements in learning and memory abilities, recovery of energy levels, and reduction of excitotoxicity damage can be achieved through activation of Adenyl cyclase enzyme by a specific phytochemical forskolin. In this study, intraperitoneal administration of 10 mg/kg 3-nitropropionic acid for 15 days in rats notably reduced body weight, worsened motor cocordination（grip strength, beam crossing task, locomotor activity）, resulted in learning and memory deficits, greatly increased acetylcholinesterase, lactate dehydrogenase, nitrite, and malondialdehyde levels, obviously decreased adenosine triphosphate, succinate dehydrogenase, superoxide dismutase, catalase, and reduced glutathione levels in the striatum, cortex and hippocampus. Intragastric administration of forskolin at 10, 20, 30 mg/kg dose-dependently reversed these behavioral, biochemical and pathological changes caused by 3-nitropropionic acid. These results suggest that forskolin exhibits neuroprotective effects on 3-nitropropionic acid-induced Huntington＇s disease-like neurodegeneration.

关键词： nerve regeneration Huntington's disease mitochondria adenyl cyclase forskolin oxidative stress basal ganglia neural regeneration

Deep Learning Framework for Classification of Emoji Based Sentiments

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Computers, Materials & Continua 2022年第8期72卷 3145-3158页

作者： Nighat parveen Shaikh Mumtaz Hussain Mahar Shah Abdul Latif University Khairpur77150Pakistan

Recent patterns of human sentiments are highly influenced by emoji based sentiments(EBS).Social media users are widely using emoji based sentiments(EBS)in between text messages,tweets and *** tiny pictures of emoji contains sufficient information to be considered for construction of classification model;but due to the wide range of dissimilar,heterogynous and complex patterns of emoji with similarmeanings(SM)have become one of the significant research areas of machine *** paper proposes an approach to provide meticulous assistance to social media application(SMA)users to classify the EBS *** methodology consists upon three layerswhere first layer deals with data cleaning and feature selection techniques to detect dissimilar emoji patterns(DEP)with similar meanings(SM).In first sub step we input set of emoji,in second sub step every emoji has to qualify user defined threshold,in third sub step algorithm detects every emoji by considering as objects and in fourth step emoji images are cropped,after data cleaning these tiny images are saved as emoji *** second step we build classification model by using convolutional neural networks(CNN)to explore hidden knowledge of emoji *** third step we present results visualization by using confusion matrix and other *** paper contributes(1)data cleaning method to detect EBS;(2)highest classification accuracy for emoji classification measured as 97.63%.

关键词： Deep learning machine vision convolutional neural networks social media emoji based sentiments

Remote sensing and geographic information systems techniques in studies on treeline ecotone dynamics

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Journal of Forestry Research 2019年第5期30卷 1543-1553页

作者： parveen K.Chhetri Eric Thai Department of Earth Science and Geography California State University Dominguez Hills

We performed a meta-analysis on over 100 studies applying remote sensing(RS)and geographic information systems(GIS)to understand treeline dynamics.A literature search was performed in multiple online databases,including Web of Knowledge(Thomson Reuters),Scopus(Elsevier),BASE(Bielefeld Academic Search Engine),CAB Direct,and Google Scholar using treeline-related *** found that RS and GIS use has steadily increased in treeline studies since *** RS and satellite imaging techniques varied from low-resolution MODIS,moderate-resolution Landsat,to high-resolution WorldView and aerial *** papers published in the 1990s used low to moderate resolution sensors such as Landsat Multispectral Scanner and Thematic Mapper,or SPOT PAN(Panchromatic)and MX(Multispectral)RS ***,we observed a rise in high-resolution satellite sensors such as ALOS,GeoEye,IKONOS,and WorldView for mapping current and potential ***,we noticed a shift in emphasis of treeline studies over time:earlier reports focused on mapping treeline positions,whereas RS and GIS are now used to determine the factors that control treeline variation.

关键词： Digital elevation model Geographic information systems Remote sensing Treeline

Predicting herbicides concentrations in paddy water and runoff to the river basin

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Journal of Environmental Sciences 2005年第4期17卷 631-636页

作者： parveen Sultana KOHGUCHI Testuyuki BISWAS Moloy NAKAGOSHI Nobukazu Graduate School for International Development and Cooperation(IDEC) Hiroshima University Kagamiyama 1-5-1 Higashi Hiroshima 739-8529JapanHiroshima Prefecture Agriculture Research CenterHaraHachihonmatuHigashi Hiroshima 739-0151 JapanGraduate School for International Development and Cooperation(IDEC) Hiroshima University Kagamiyama 1-5-1 Higashi Hiroshima 739-8529JapanDepartment of Environmental Studies IDECHiroshima UniversityHigashi HiroshimaJapan 739-8529

This study was conducted to investigate the dissipation pattern and runoff of herbicides to the river basin from the paddy fields. Pesticide paddy field model(PADDY) was applied to predict herbicide concentration in paddy fields. A field study was conducted in a paddy farm of Higashi Hiroshima City, Hiroshima Prefecture, Japan in the year of 2003 paddy season. The herbicides were mefenacet, thiobencarb, and bensulfuron methyl. The sample water was analyzed by using gas chromatography and HPLC after solid phase extraction. Predicted dissipation rate of thiobencarb in paddy water was higher(DT_ 50 = 4 36) than that measured, with a lower k value(-0 069). Two weeks after application no thiobencarb was detected in the drainage channel and down stream. In the down stream, thiobencarb was detected until 3 d after application, with a range of 0 02% to 0 08% of applied herbicide. The predicted dissipation rate(k) and half-life(DT_ 50 ) of mefenacet was not significantly different from that of measured. In the drainage channel, upstream and downstream mefenacet was found during the whole study period. In downstream, the maximum concentration of mefenacet was present 0 61% of applied in the paddy field on 3DAH. The dissipation rate(k) of BSM varied from -0 0860 to -0 1059 to with half-life(DT_ 50 ) 3 5 and 2 84 d. In upstream water, no BSM was detected except trace amounts(0 01 μg/L) at 3 d after application. However, in the drainage channel 8%, 6% and 1 58% of applied BSM was present at 0, 1 and 3 d after application respectively. In the down stream, the highest concentration was 1 06%, shortly after application.

关键词： paddy field pesticide paddy field model(PADDY) herbicide dissipation runoff

Electrochemical and electronic properties of nitrogen doped fullerene and its derivatives for lithium-ion battery applications

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Journal of Energy Chemistry 2018年第2期27卷 528-534页

作者： parveen Sood Ki Chul Kim Seung Soon Jang School of Materials Science and Engineering Georgia Institute of Technology Atlanta CA 30332-0245. USA Department of Chemical Engineering Konkuk University Seoul 05029 Republic of Korea Institute for Electronics and Nonotechnology Georgia Institute of Technology Atlanta GA 30332-0245 USA Parker H. Petit Institute for Bioengineering and Bioscience Georgia Institute of Technology Atlanta GA 30332-0245 USA

We have studied the redox potentials and electronic properties of C60 and C59N using density functional theory method. It is found that doping C60 with one nitrogen atom results in a slight increase in redox potential. Next, we have also studied C59N functionalized with various redox-active oxygen containing functional groups and strongly electron withdrawing functional groups. It is found that the intrinsic electronic structure of the molecule is the major determinant of the redox potential. Our DFT calculations show that the electron affinity to redox potential of functionalized C59N is correlated with the LUMO of the systems very well. This is the first systematic study on the redox properties and electronic structures of N-doped C60 systems.

关键词： DFT Redox potential C60 Doping Li-ion battery

Effect of cooling media on bead geometry,microstructure,and mechanical properties of wire arc additive manufactured IN718 alloy

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Advances in Manufacturing 2024年第1期12卷 124-149页

作者： parveen Kumar Satish Kumar Sharma Ratnesh Kumar Raj Singh Department of Mechanical Engineering Thapar Institute of Engineering and TechnologyPatialaPunjab147004India

This work aims to present and explore thermal management techniques for the wire arc additive manufacturing(WAAM)of IN718 *** heat can be mitigated via air or water *** this study,the material was deposited under four different heat-input conditions with air or water *** air cooling,the layer is deposited in a normal atmospheric air environment,whereas with water cooling,the material is deposited inside a water tank by varying the water *** validate the air and water cooling thermal management techniques,IN718 single-pass and multilayer linear walls were deposited using the bidirectional gas metal arc welding based WAAM setup under four different heat input *** the deposition of single layers,the temperature profiles were recorded,and the geometric and microstructural features were *** multilayer wall structures,the mechanical properties(hardness,tensile strength,and elongation)were determined and assessed using the corresponding microstructural features explored through scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),and electron backscatter diffraction(EBSD)*** microstructure observed through SEM analysis in the building direction was found to be nonhomogenous compared with that in the deposition ***,water cooling was found to govern bead characteristics,such as wall width and *** grain size and anisotropy of the mechanical properties also decreased in the water-cooled ***,water cooling is an economical and efficient method to mitigate excessive heat accumulation in WAAM-deposited IN718.

关键词： Air cooling Water cooling IN718 Bead characteristics Microstructure Electron backscatter diffraction(EBSD)