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Formalising and Detecting Community Structures in Real World Complex Networks

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Journal of Systems Science & Complexity 2021年第1期34卷 180-205页

作者： kumar pawan DOHARE Ravins School of Sciences Indira Gandhi National Open UniversityNew Delhi 110068India Centre for Interdisciplinary Research in Basic Sciences Jamia Millia IslamiaNew Delhi 110025India

Community structure is an integral characteristic of real world networks whichever processes or areas they emerge from. This paper addresses the problem of community structure detection theoretically as well as computationally. The authors introduce a number of concepts such as the neighbourhood and strength of a subgraph, p-community, local maximal p-community, hubs, and outliers that play elemental role in formalising the concept of community structure in complex networks. A few preliminary results have been derived that lead to the development of an algorithm for community structure detection in undirected unweighted networks. The algorithm is based on a local seed expansion strategy that uses the concept of interaction coefficient. The authors have analysed the algorithm on a number of parameters such as accuracy, stability, and quality on synthetic and real world networks from different areas.

关键词： Algorithm hub local maximal p-community outlier p-community strength of a subgraph

A neighborhood proximity based algorithm for overlapping community structure detection in weighted networks

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Frontiers of Computer Science 2019年第6期13卷 1353-1355页

作者： pawan kumar Ravins DOHARE Centre for Interdisciplinary Research in Basic Sciences Jamia Millia IslamiaNew Delhi-110025India

1 Introduction Many real networks are inherently composed of overlapping structure at modular level where nodes have multiple ***,many real networks are equipped with several metadata such as ground truth,node and edge weights which make the whole business of community detection ***,there are a few well known algorithms,e.g.,CPMw[1]that can detect overlapping community structure in weighted *** it comes to the application of an algorithm,the desired output depends on the right choice of parameters.

关键词： networks structure algorithm

Coordination polymers： Challenges and future scenarios for capture and degradation of volatile organic compounds

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Nano Research 2016年第11期9卷 3181-3208页

作者： Kowsalya Vellingiri pawan kumar Ki-Hyun Kim Department of Civil and Environmental Engineering Hanyang uniVersity 222 Wangsimni-RoSeoul 04763Republic of Rorea Department of Nano Sciences and Materials Central University of Jammu Jammu 181143 India

Over the past few decades, coordination polymers/metal organic frameworks （CPs/MOFs） have drawn a great deal of attention for diverse applications due to their advantages of intrinsically ttLnable chemical structure, flexible architecture, high pore volume, high surface area, multifunctional properties, etc. To date, numerous CPs/MOFs have been developed and employed for the treatment and control of gaseous pollutants, such as volatile organic compounds （VOCs）, through capture, sorptive removal, and catalytic degradation. Nevertheless, there are also some key drawbacks and challenges for the practical application of these systems （e.g., poor selectivity, high energy （and fiscal） cost, high synthesis cost, low capacity, and difficulties in regeneration and recycling）. In this review, recent developments in CPs/MOFs research are described with their associated mechanisms for capture, sorptive removal, and catalytic degradation of VOCs. To this end, we discuss the key variables and challenges for afforded abatement of VOCs through CPs/MOFs technologies. Hopefully, this review will help the scientific community set future directions for the advancement of CPs/MOFs techniques for the effective management of diverse environmental issues.

关键词： coordination polymers/metal organic frameworks(CPs/MOFs) volatile organic compounds sorptive removalcatalytic degradation

Recent development in upconversion nanoparticles and their application in optogenetics:A review

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Journal of Rare Earths 2022年第6期40卷 847-861,I0001页

作者： Madhumita Patel Maninder Meenu Jitender kumar Pandey pawan kumar Rajkumar Patel Department of Chemistry and Nano Science Ewha Womans UniversitySeodaemun-guSeoul120-750South Korea College of Biosystems Engineering and Food Science Zhejiang UniversityHangzhou 310058China School of Basic and Applied Sciences Adamas UniversityKolkata700126India Institut National de la Recherche Scientifique-Centreénergie Materiaux Télecommunications(INRS-EMT) VarennesQCCanada Department of Chemistry and Biochemistry University of Oklahoma101 Stephenson ParkwayNormanOK73019United States Energy&Environmental Science and Engineering(EESE) Integrated Science and Engineering Division(ISED)Underwood International CollegeYonsei University85 Songdogwahak-roYeonsu-guIncheon21983South Korea

Ion channels present in the plasma membrane are responsible for integration and propagation of electric signals,which transmit information in nerve *** of these ion channels leads to many neurological ***,optogenetic technology has gained a lot of attention for the manipulation of neuronal *** is a neuromodulation approach that has been developed to control neuronal functions and activities using *** lanthanide-doped upconversion nanoparticles(UCNPs)absorb low energy photons in near-infrared(NIR) window and emit high energy photons in the visible spectrum region via nonlinear *** the last few decades,UCNPs have gained great attention in various bio-medical applications such as bio-imaging,drug delivery and *** near-infrared illumination is considered more suitable for optogenetics application,due to its lower degree of light attenuation and higher tissue penetration compared to visible ***,UCNPs have been considered as the new promising candidates for optogenetics *** nanoparticlemediated optogenetic systems provide a great opportunity to manipulate the ion channel in deep ***,we summarize the upconversion photoluminescence in lanthanide doped nanomaterials and its mechanisms and several approaches adopted to tune emission color or enhance upconversion *** advances of lanthanide-doped UCNPs design strategy and their mechanism are ***,we discuss the neural circuitry modulation using upconversion nanoparticles mediated ***,the future perspectives towards optogenetics are also included.

关键词： Lanthanide Upconversion Optogenetics Nanoparticles Neuronal modulation Rare earths

An indicator-based approach to assess village-level social and biophysical vulnerability of agriculture communities in Uttarakhand,India

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Journal of Mountain Science 2016年第12期13卷 2260-2271页

作者： Roopam SHUKLA Kamna SACHDEVA pawan kumar JOSHI Department of Natural Resources TERI University School of Environmental Sciences Jawaharlal Nehru University

With the growing recognition to myriad forms of current and future threats in the mountain agriculture systems,there is a pressing need to holistically understand the vulnerability of mountain agriculture *** study aims to assess the biophysical and social vulnerability of agriculture communities using an indicator-based approach for the state of Uttarakhand,India.A total of 14 indicators were used to capture biophysical vulnerability and 22 for social vulnerability profiles of15285 *** analysis was done at village level with weights assigned to each indicator using Analytical Hierarchical Process(AHP).The results of the study highlight the presence of very high biophysical vulnerability(0.82 ± 0.10) and high social vulnerability(0.65 ± 0.15) within the *** on the results,it was found that incidences of high biophysical vulnerability coincide with presence of intensified agriculture land and absence of dense *** social vulnerability scores were found in villages with an absence of local institutions(like Self Helping Groups(SHGs)),negligible infrastructure facilities and higher occupational dependence on agriculture.A contrast was observed in the vulnerability scores of villages present in the three different altitudinal zones in the study area,indicating respective vulnerability generating conditions existing in these three *** vulnerability was recorded to be highest in the villages falling in the lower zone and lowest in the upper zone villages;whereas,social vulnerability was found to be highest in the middle zone villages and lowest in lower zone *** study aids policy makers in identifying areas for intervention to expedite agriculture adaptation planning in the ***,the adaptation programmes in the region need to be more context-specific to accommodate the differential altitudinal vulnerability profiles.

关键词： Social vulnerability Biophysical vulnerability Mountain agriculture communities AHP Uttarakhand

Habitat Range of two Alpine Medicinal Plants in a Trans-Himalayan Dry Valley,Central Nepal

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Journal of Mountain Science 2009年第1期6卷 66-77页

作者： Bharat Babu shrestha Pramod kumar JHA Central Department of Botany Tribhuvan UniversityKathmanduNepal

Understanding of the habitat range of threatened Himalayan medicinal plants which are declining in their abundance due to high anthropogenic disturbances is essential for developing conservation strategies and agrotechnologies for cultivation. In this communication, we have discussed the habitat range of two alpine medicinal plants, Aconitum naviculare （Bruehl） Stapf and Neopicrorhiza scrophulariiflora （Pennel） Hong in a trans-Himalayan dry valley of central Nepal, Manang district. They are the most prioritized medicinal plants of the study area in terms of ethnomedicinal uses. A. naviculare occurs on warm and dry south facing slopes between 4090-4650 m asl along with sclerophyllous and thorny alpine scrubs, while N. scrophulariiflora is exclusively found on cool and moist north facing slope between 4000 and 4400 m asl where adequate water is available from snow melt to create a suitable habitat for this wetland dependent species. The soil in rooting zone of the two plants differs significantly in organic carbon （OC）, organic matter （OM）, total nitrogen （N） and carbon to nitrogen （C/N） ratio. Due to cool and moist condition of N. scrophulariiflora habitat, accumulation of soil OC is higher, but soil N content is lower probably due to slow release from litter, higher leaching loss and greater retention in perennial live biomass of the plant. The C/N ratio of soil is more suitable in A. navuculare habitat than that of N scrophulariiflora for N supply. Warm and sunny site with N rich soil can be suitable for cultivation ofA. naviculare, while moist and cool site with organic soil for N. scrophulariiflora. The populations of both the plants are fragmented and small. Due to collection by human and trampling damage by livestock, the population of A. naviculare was found absent in open areas in five of the six sampling sites and it was confined only within the bushes of alpine scrubs. For N. serophulariiflora, high probability of complete receding of small glaeiers may be

关键词： Aconitum naviculare Neopicrorhizascrophulariiflora habitat degradation nitrogen organic carbon radiation Manang Nepal

Implications of Climate Change on Streamflow of a Snow-Fed River System of the Northwest Himalaya

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Journal of Mountain Science 2013年第4期10卷 574-587页

作者： Vaibhav SHARMA Varunendra Dutta MISHRA pawan kumar JOSHI Snow and Avalanche Study Establishment Chandigarh 160036 India TERI University Institutional AreaDelhi 110070 India

Air temperature and snow cover variability are sensitive indicators of climate change. This study was undertaken to forecast and quantify the potential streamflow response to climate change in the Jhelum River basin. The implications of air temperature trends （＋0.11℃decade） reported for the entire north-west Himalaya for past century and the regional warming （＋0.7℃/decade） trends of three observatories analyzed between last two decades were used for future projection of snow cover depletion and stream flow. The streamflow was simulated and validated for the year 2007-2008 using snowmelt runoff model （SRM） based on in-situ temperature and precipitation with remotely sensed snow cover area. The simulation was repeated using higher values of temperature and modified snow cover depletion curves according to the assumed future climate. Early snow cover depletion was observed in the basin in response to warmer climate. The results show that with the increase in air temperature, streamfiow pattern of Jhelum will be severely affected. Significant redistribution of streamflow was observed in both the scenarios. Higher discharge was observed during spring-summer months due to early snowmelt contribution with water deficit during monsoon months. Discharge increased by 5%-40% during the months of March to May in 2030 and 2050. The magnitude of impact of air temperature is higher in the scenario-2 based on regional warming. The inferences pertaining to change in future streamflow pattern can facilitate long term decisions and planning concerning hydro-power potential, waterresource management and flood hazard mapping in the region.

关键词： Snowmelt Snow cover depletion curve(SCDC) Climate change Global warming Streamflow SRM Jhelum

Tracking sources and paleotectonic settings of Mesozoic sandstones in interlinked rift basins of western India:An integrated approach using petrography and heavy mineral chemistry

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Journal of Palaeogeography 2022年第2期11卷 173-193页

作者： pawan kumar Rajak Angana Chaudhuri Naraga Prabhakar Santanu Banerjee Department of Earth Sciences Indian Institute of Technology BombayMumbai 400076India

Based on integration of field,petrographic and heavy mineral chemical data,this study highlights the source and tectonic setting of the Mesozoic sandstones of Kutch,Saurashtra,Narmada and Cambay basins at the western margin of India,formed by the progressive splitting of the eastern *** Kutch Basin is dominated by arkosic sandstone,whereas Saurashtra,Narmada and Cambay basins show the predominance of sub-arkose and *** modal analyses of framework grains in Kutch sandstones indicate basement uplift and transitional continent *** contrast,the sandstones of Saurashtra,Narmada and Cambay basins bear imprints of recycled orogenic and craton interior *** presence of abraded and detrital quartz overgrowth and rounded zircons in most sandstones reveal the recycling of sediments in these *** and rutile mineral compositions constrain the possible lithology of source *** tourmaline mineral chemistry(Ca-Fe_(tot)-Mg plot)suggests the derivation of sediments from various sources,including Li-poor granitoids associated with pegmatites,aplites,Ca-poor metapelites,metapsammites and quartz-tourmaline-rich granitic *** compositions of rutile grains(Cr *** plot)in sandstones indicate metapelitic *** gamut of all mineral chemical data supports the predominance of sediment sources from quartzo-feldspathic rocks with minor inputs from mafic *** on available paleocurrent data and correlation of source compositions,we infer that the Mesozoic sediments of Kutch,Saurashtra,Narmada and Cambay basins were primarily sourced by various lithologies of the Aravalli *** Narmada Basin possibly received additional sediment input from the Bundelkhand Craton.

关键词： Mesozoic sandstones Rift basins Tourmaline chemistry Rutile chemistry Kutch Basin Saurashtra Basin Cambay Basin Narmada Basin

Multifunctional characteristics of 3D printed polymer nanocomposites under monotonic and cyclic compression

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Defence Technology（防务技术） 2023年第12期30卷 13-22页

作者： pawan Verma Jabir Ubaid Fahad Alam Suleyman Deveci S.kumar Department of Mechanical Engineering Khalifa University of Science and TechnologyMasdar InstituteMasdar CityP.O.Box 54224Abu DhabiUnited Arab Emirates Borouge Pte.Ltd. Innovation CentreSas Al Nakhl6951Abu DhabiUnited Arab Emirates James Watt School of Engineering University of GlasgowGlasgowG128QQUK

This study presents the multifunctional characteristics of multi-walled carbon nanotube(MWCNT)/polypropylene random copolymer(PPR) composites enabled via fused filament fabrication(FFF) under monotonic and quasi-static cyclic compression. Utilizing in-house MWCNT-engineered PPR filament feedstocks, both bulk and cellular composites were realized. The morphological features of nanocomposites were examined via scanning electron microscopy, which reveals that MWCNTs are uniformly dispersed. The uniformly dispersed MWCNTs forms an electrically conductive network within the PPR matrix, and the resulting nanocomposite shows good electrical conductivity(~10^(-1)S/cm), improved mechanical performance(modulus increases by 125% and compressive strength increases by 25% for 8 wt% MWCNT loading) and pronounced piezoresistive response(gauge factor of 27.9-8.5 for bulk samples)under compression. The influence of strain rate on the piezoresistive response of bulk samples(4 wt% of MWCNT) under compression was also measured. Under repeated cyclic compression(2% constant strain amplitude), the nanocomposite exhibited stable piezoresistive performance up to 100 cycles. The piezoresistive response under repeated cyclic loading with increasing strain amplitude of was also *** gauge factor of BCC and FCC cellular composites(4 wt% of MWCNT) with a relative density of 30%was observed to be 46.4 and 30.2 respectively, under compression. The higher sensitivity of the BCC plate-lattice could be attributed to its higher degree of stretching-dominated deformation behavior than the FCC plate-lattice, which exhibits bending-dominated behavior. The 3D printed cellular PPR/MWCNT composites structures were found to show excellent piezoresistive self-sensing characteristics and open new avenues for in situ structural health monitoring in various applications.

关键词： Carbon nanotubes Nanoengineered polymer composites 3D printing Piezoresistive self-sensing Lattice structures