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Load shedding strategy coordinated with storage device and D-STATCOM to enhance the microgrid stability

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Protection and Control of Modern Power Systems 2019年第1期4卷 262-280页

作者： Sheetal Chandak pritam Bhowmik Pravat kumar Rout Electrical Engineering Department Siksha‘O’Anusandhan UniversityBhubaneswar751030India Electrical and Electronics Engineering Department Siksha‘O’Anusandhan UniversityBhubaneswar751030India

Recently microgrids have drawn a potential attraction by fulfilling the environmental demands and the increasing energy demands of the end-users. It is necessary to focus on various protection and control aspects of a microgrid. During the transition between the grid-following and grid-forming modes, the voltage and the frequency instability due to the power mismatch condition becomes the major point of concern. Therefore, the paper executes a frequency-active power and voltage-reactive power drooping control strategy for the precise power-sharing among the distributed power generators. Furthermore, to handle the power deficit scenarios and to maintain the system stability, a system independent and priority-based adaptive three-stage load shedding strategy is proposed. The sensitivity of the strategy depends on the system inertia and is computed according to the varying absolute rate-of-change-of-frequency. The strategy incorporates the operation of battery storage system and distributed static compensator (D-STATCOM) in the microgrid, to provide a reliable power supply to the customers for a considerable time instead of a sudden load shedding. The effectiveness of the proposed strategies is investigated on a scaled-down modified IEEE 13-bus microgrid system on the podium of MATLAB 2015b through the time-domain simulation.

关键词： Microgrid Power-sharing Load shedding High inertia distributed generators Inertia-less distributed generators Battery storage system D-STATCOM

Syncytes during male meiosis resulting in 2n pollen grain formationin Lindelofia longiflora ***

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Journal of Systematics and Evolution 2011年第5期49卷 406-410页

作者： Vijay kumar SINGHAL Pawan kumar rana Puneet kumar Department of Botany Punjabi University

Lindelofia longiflora(Royle ex Benth.) ***(Cl.) Brand(Family:Boraginaceae) is investigated cytologically(n = 12) for the first time from the cold deserts of Pangi Valley,Chamba District(Himachal Pradesh) in *** report the formation of syncytes and 2n pollen grains in the *** meiosis,the majority of the pollen mother cells(PMCs) exhibited 12 bivalents,equal segregation of chromosomes during anaphases,regular tetrads,and normal-sized pollen grain ***,two proximate PMCs fused during the early stages of prophase-I and resulted in the formation of *** frequency of syncytes in the accession is rather low,at 25 out of 1866(1.33%).Such syncyte PMCs are detectable during meiosis due to their larger size compared to typical *** syncytes or polyploid cells showed normal 24 bivalents and depicted perfectly regular meiotic *** the products of such PMCs yield 2n or larger sized pollen grains that are almost double the size of typical normal or n pollen *** origin of syncytes as a consequence of the fusion of meiocytes during the early stages of meiosis-I could be attributed to low temperature stress conditions prevailing in the Pangi Valley,where temperature during May and June dip to below freezing,the time the plants enters the reproductive/flowering bud *** is possible that such apparently fertile 2n pollen grains originating from syncytes might play a role in the origin of intraspecific polyploids in the species.

关键词： bivalents cold deserts low temperature stress Pangi Valley PMCs pollen grains.

Determining bioclimatic space of Himalayan alder for agroforestry systems in Nepal

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Plant Diversity 2018年第1期40卷 1-18页

作者： Santosh kumar rana Hum Kala rana Krishna kumar Shrestha Suresh Sujakhu Sailesh Ranjitkar Key Laboratory{or Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Systematics and Biodiversity Unit Central Department of BotanyTribhuvan UniversityKirtipurKathmanduNepal jade Consult Private Limited KabilmargThapathaliKathmanduPOB 746Nepal World Agroforestry Centre East and Central Asia 132 Lanhei RdHeilongtanKunmingChina

Himalayan alder species are proven to be very useful in traditional as well as contemporary agroforestry practice. These nitrogen-fixing trees are also useful in the land restoration. Therefore, understanding the distribution of Himalayan alder and the potential zone for plantation is meaningful in the agroforestry sector. Suitable climatic zones of Alnus spp. were modelled in Max Ent software using a subset of least correlated bioclimatic variables for current conditions(1950 -2000), topographic variables(DEM derived) and Landuse Landcover(LULC) data. We generated several models and selected the best model against random models using ANOVA and t-test. The environmental variables that best explained the current distribution of the species were identified and used to project into the future. For future projections, ensemble scenarios of climate change projection derived from the results of 19 Earth System Models(ESM) were used. Our model revealed that the most favorable conditions for Alnus nepalensis are in central Nepal in the moist north-west facing slope, whereas for Alnus nitida they are in western *** major climatic factor that contributes to Alnus species distribution in Nepal appears to be precipitation during the warmest quarter for A. nepalensis and precipitation during the driest quarter for A. nitida. Future projections revealed changes in the probability distribution of these species, as well as where they need conservation and where they can be planted. Also, our model predicts that the distribution of Alnus spp. in hilly regions will remain unchanged, and therefore may represent sites that can be used to revitalize traditional agroforestry systems and extract source material for land restoration.

关键词： Alder Agroforestry Species distribution modeling Climate change MaxEnt

Predicting the impact of climate change on the distribution of two threatened Himalayan medicinal plants of Liliaceae in Nepal

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Journal of Mountain Science 2017年第3期14卷 558-570页

作者： rana Santosh kumar rana Hum Kala GHIMIRE Suresh Kulllar SHRESTHA Krishna kumar RANJITKAR Sailesh Key Laboratory for Plant Diversity and Biogeography of EastAsia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Central Department of Botany Tribhuvan UniversityKirtipurKathmanduNepal World Agroforestry Centre East and Central Asia 132 Lanhei RdHeilongtanKunming 650201China

Predicting the potential distribution of medicinal plants in response to climate change is essential for their conservation and management. Contributing to the management program, this study aimed to predict the distribution of two threatened medicinal plants, Fritillaria cirrhosa and Lilium nepalense. The location of focal species gathered from herbarium specimen housed in different herbaria and online databases were geo-referenced and checked for spatial autocorrelation. The predictive environmental variables were selected, and MaxEnt software was used to model the current and future distributions of focal species. Four Representative Concentration Pathway （RCP） trajectories of the BCC-CSMI.1 model were used as the future （2050） projection layer. The MaxEnt modelling delineated the potential distribution of F. cirrhosa and L. nepalense. The current suitability is projected towards Central and Eastern Hilly/Mountainous regions. Both species gain maximum suitability in RCP 4.5 which decline towards other trajectories for L. nepalense. Overall, both the focal species shift towards the north-west, losing their potential habitat in hilly and lower mountainous regions by 2050 across all trajectories. Our results highlight the impact of future climate change on two threatened and valuable species. The results can be further useful to initiate farming of these medicinally and economically important species based on climatically suitable zone and for designing a germplasm conservation strategy.

关键词： Commercial exploitation Conservation Lily Fritillaria cirrhosa Lilium nepalense MaxEntmodelling Species distribution

Molecular phylogeny,biogeography and character evolution of the montane genus Incarvillea Juss.(Bignoniaceae)

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Plant Diversity 2021年第1期43卷 1-14页

作者： Santosh kumar rana Dong Luo Hum Kala rana Shaotian Chen Hang Sun CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of the Chinese Academy of Sciences Beijing 100049China College of Pharmaceutical Science Yunnan University of Chinese MedicineKunming 650500China

The complex orogeny of the Himalaya and the Qinghai-Tibet Plateau(QTP)fosters habitat fragmentation that drives morphological differentiation of mountain plant ***,determining phylogenetic relationships between plant subgenera using morphological characters is ***,we used both molecular phylogeny and historical biogeographic analysis to infer the ancestral states of several vegetative and reproductive characters of the montane genus *** determined the taxonomic position of the genus Incarvillea within its family and inferred the biogeographical origin of taxa through Bayesian inference(BI),maximum likelihood(ML)and maximum parsimony(MP)analyses using three molecular data sets(trnL-trnF sequences,nr ITS sequences,and a data set of combined sequences)derived from 81%of the total species of the genus *** the genus-level phylogenetic framework,we examined the character evolution of 10 key morphological characters,and inferred the ancestral area and biogeographical history of the *** analyses revealed that the genus Incarvillea is monophyletic and originated in Central Asia during mid-Oligocene ca.29.42 *** earliest diverging lineages were subsequently split into theWestern Himalaya and Sino-Himalaya during the early Miocene ca.21.12 *** lineages resulted in five re-circumscribed subgenera(Amphicome,Olgaea,Niedzwedzkia,Incarvillea,and Pteroscleris).Moreover,character mapping revealed the ancestral character states of the genus Incarvillea(e.g.,suffruticose habit,cylindrical capsule shape,subligneous capsule texture,absence of capsule wing,and loculicidal capsule dehiscence)that are retained at the earliest diverging ancestral nodes across the *** phylogenetic tree of the genus Incarvillea differs from previously proposed phylogenies,thereby recommending the placement of the subgenus Niedzwedzkia close to the subgenus Incarvillea and maintaining two main divergent lineages.

关键词： Biodiversity hotspots Biogeography Incarvillea Molecular phylogeny Phytools Stochastic character mapping

Some Investigations on Hybrid Fuzzy IPD Controllers for Proportional and Derivative Kick Suppression

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International Journal of Automation and computing 2016年第5期13卷 516-528页

作者： Vineet kumar K.P.S.rana Division of Instrumentation and Control Engineering Netaji Subhas Institute of Technology(NSIT)

Proportional and derivative kick i.e., a large change in control action of a proportional plus integral plus derivative （PID） controller due to a sudden change in reference set-point is generally undesired in process industry. Therefore, the structure of conventional parallel PID controller is modified to integral minus proportional derivative （I-PD） controller. In this paper, three hybrid fuzzy IPD controllers such as a fuzzy I-fuzzy PD （FI-FPD） controller and its hybrid combinations with its conventional counterpart such as fuzzy I-PD （FI-PD） and I-fuzzy PD （I-FPD） are presented in view of above industrial problem. These controllers are based upon the counterpart conventional I-PD controller and contains analytical formulae. Computer simulations are carried out to evaluate the performance of hybrid fuzzy controllers along with conventional I-PD and PID controllers for set-point tracking and disturbance rejection for an induction motor in closed loop using LabVIEWTM environment. The gains of conventional and hybrid fuzzy controllers are tuned using genetic algorithm （GA） for minimum overshoot and settling time. It has been observed that hybrid fuzzy controllers along with the conventional I-PD controller significantly remove the kick from the control action in reference set-point tracking. However, in disturbance rejection, I-PD and FI-PD controllers fail to eliminate the kick from the control signal. In contrast, FI-FPD and I-FPD controllers considerably reduced spikes from the control action in disturbance rejection. Among the conventional and hybrid fuzzy IPD controllers, FI--FPD demonstrates much better set-point tracking and disturbance rejection response with spike free control action.

关键词： Proportional plus integral plus derivative (PID) integral minus proportional derivative (I-PD) hybrid fuzzy IPD con- troller proportional kick derivative kick.

Plant endemism in the Nepal Himalayas and phytogeographical implications

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Plant Diversity 2019年第3期41卷 174-182页

作者： Achyut Tiwari Yadav Uprety Santosh kumar rana Department of Botany Tri-Chandra Campus Tribhuvan University Kathmandu Nepal Central Department of Botany Tribhuvan University Kirtipur Kathmandu Nepal Research Centre for Applied Science and Technology Tribhuvan University Kathmandu Nepal IUCN (International Union for Conservation of Nature) Kathmandu Nepal Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences Kunming 650201 Yunnan China University of Chinese Academy of Sciences Beijing 100049 China

Nepal is located in the central part of the greater Himalayan range with a unique series of mountain chains formed by recent mountain building geological events. As one of the youngest mountains in the world it contributes to diversity of plants and also provided barriers to and corridors through which plants migrated during the ice ages. The higher altitudinal variation with the high mountains, deep river valleys and lowland plains combine with the effects of the summer monsoon and dry winter result with an extraordinary diversity of ecosystems including flora and fauna in a relatively small land area. The existing checklists for Nepal record some 6000 species of flowering plants and about 530 ferns. However, the botanical experts estimate that numbers may go up to 7000 when the poorly known remote regions are fully explored. The information on plant endemism in Nepal Himalaya is not adequately known as Nepal is still struggling to complete long awaited Flora of Nepal project. Endemic species are confined to specific areas and are the first to be affected by land use and other global changes. We sought to explore the spatial distribution of endemic plant species in Nepal in relation to the consequences associated with climatic and geologic changes over time in the region with the help of published literature. It was found that the endemism showed marked spatial variation between open moist habitat and dry inner valleys, the former with higher endemism. The updated records showed 312 flowering plant species to be endemic to Nepal with higher endemism around the elevation of 3800e4200 m at sea level. The recent human population explosion, intensified deforestation, habitat fragmentation and modern day environmental changes are posing greater threats to endemic plant in Nepal. The conservation status and threats to these peculiar species are unknown. Nevertheless, environmental degradation and high poverty rates create a potent mix of threats to biodiversity in this l

关键词： Himalaya Topography Endemism

Resistance and resilience of soil biological indicators:A case study with multi-walled carbon nanotube

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Pedosphere 2024年第3期34卷 664-675页

作者： Shagufta YASMEEN Nintu MANDAL Anupam DAS pritam GANGULY Sanjay kumar Rajiv RAKSHIT Department of Soil Science and Agricultural Chemistry Bihar Agricultural UniversitySabourBhagalpur 813210(India) Department of Agronomy Bihar Agricultural UniversitySabourBhagalpur 813210(India)

Soil ecosystem is experiencing stresses due to climate change,and soil inhabitants try to demonstrate their inherent resistance and resilience against those *** of nanomaterials as agricultural inputs could bring shifts in resistance and resilience patterns of soil microbes and associated enzymes,especially under short-term heat *** this background,the impacts of multi-walled carbon nanotube(MWCNT)on the resistance and resilience of soil biological indicators were *** incubation experiment was conducted with varied MWCNT concentrations(0,50,100,250,and 500 mg kg-1soil)for 90 d after 24-h heat stress at 48±2?C to assess the impacts of MWCNT on soil enzyme activities and microbial populations vis-à-vis their resistance and resilience indices under short-term exposure to heat *** activities were reduced after exposure to heat *** indices of enzyme activities were enhanced by MWCNT application on day 1 after heat stress,whereas there was no recovery of enzyme activities after 90-d *** soil enzyme activities,resistance index values of soil microbial populations followed the similar trend and were improved by MWCNT ***-walled carbon nanotube has the potential to improve resistance indices of soil enzyme activities and microbial populations under heat stress,although they could not recover to their original state during periodical incubation after heat *** study helps to understand the relative changes of biological indicators under MWCNT and their ability to withstand heat stress.

关键词： enzyme activity heat stress microbial population nanomaterial recovery

Synthesis and characterization of rare earth metal doped tungsten trioxide photocatalyst for degradation of Rhodamine B dye

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Journal of Rare Earths 2023年第9期41卷 1302-1310,I0002页

作者： Pooja Nehra Amita Khatri Anil kumar Satyendra Singh Pawan S.rana Department of Physics Deenbandhu Chhotu Ram University of Science and TechnologyMurthal1339SonipatHaryanaIndia Special Centre for Nanoscience Jawaharlal Nehru University New Delhi10067India

Nowadays,it is concern for researchers that due to high recombination rate of photogenerated charge carriers in tungsten trioxide(WO_(3)) nanoparticles,the future applications are limited in the field of *** we attempt to synthesize tungsten trioxide nanoparticles with different doping concentrations of lanthanum i.e.2 wt%,4 wt%,6 wt% and 8 wt%.The synthesized samples were characterized by using various characterization techniques:X-ray diffraction(XRD),Raman spectroscopy,Fourier transform infrared spectroscopy(FTIR),photoluminescence spectra(PL),transmission electron microscopy(TEM),energy dispersive X-ray(EDX) and UV-Vis ***_(3) retains its monoclinic structure even after doping which was confirmed by XRD *** helps to descry functional groups present in the *** size of nanoparticles was calculated by using *** confirms the absence of any impurity in the synthesized *** spectroscopy confirms the presence of a large number of imperfections induced in the lattice of WO_(3).The rate of recombination was analyzed by photoluminescence(PL) spectroscopy and is minimum in 4 wt% doping of *** optical bandgap was calculated using UV-Vis spectroscopy and becomes narrow along with the doping ***,it is found that doping of La in WO_(3) has considerably ameliorate the photocatalytic activity by reducing rate of recombination due to the trapping of electrons by defects introduced in the *** decolorization of Rhodamine B(RhB) dye was performed and the values of c/c_0 and rate constant(k) confirm that the 4 wt% doping shows maximum degradation *** kinetic study for photodegradation of Rhodamine B was done by using various kinetic models and results show that the reaction follows first order kinetics very ***,optimum doping of lanthanum increases the decolorization ability of WO_(3) towards RhB dye.

关键词： Photocatalytic activity WO_(3)nanoparticles Rhodamine B dye Rare earth doping Visible light