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In-vitro Androgenesis in Rice: Advantages, Constraints and Future Prospects 被引量:5
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作者 Rukmini MISHRA Gundimeda Jwala Narashima RAO 《Rice science》 SCIE CSCD 2016年第2期57-68,共12页
In vitro androgenesis is an important component of plant biotechnology when the pollen grains are forced to switch from their normal pollen developmental pathway towards an embryogenic route. Haploid and doubled haplo... In vitro androgenesis is an important component of plant biotechnology when the pollen grains are forced to switch from their normal pollen developmental pathway towards an embryogenic route. Haploid and doubled haploid produced through androgenesis have long been recognized as a valuable tool in plant breeding as it can shorten the breeding cycle, fix agronomic characters in homozygous state and enhance the selection efficiency of useful recessive agronomic traits. Recently, doubled haploids have been largely recognized as an important component of crop improvement through genome mapping, quantitative trait locus analysis, and genetic mutation, and as targets for genetic transformation programs. Thus, this review is focused mainly on various facets of doubled haploid in the chief staple food crop rice and sights its recent applications in plant breeding, genetics and genomics. 展开更多
关键词 in vitro androgenesis doubled haploid HAPLOID RICE
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Biotechnological intervention in Betelvine(Piper betle L.):A review on recent advances and future prospects 被引量:2
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作者 Suryasnata Das Reena Parida +2 位作者 I.Sriram Sandeep Sanghamitra Nayak Sujata Mohanty 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第10期916-923,共8页
Betelvine(Piper betle L.) is cultivated for its deep green heart shaped leaf for(15-20) million Indian and 2 billion foreign consumers annually. The crop provides Rs(6 000-7 000) million of national income per year an... Betelvine(Piper betle L.) is cultivated for its deep green heart shaped leaf for(15-20) million Indian and 2 billion foreign consumers annually. The crop provides Rs(6 000-7 000) million of national income per year and at the same time leaves worth Rs(30-40) million is exported to other countries. The leaves are not only used directly for chewing purposes but also possesses antioxidant, anti-inflammatory, anti-apoptotic, anti-cancer and anti-microbial properties. Besides, the leaves also contain eugenol rich essential oil(1%-3%) which is the source for medicine, stimulant, antiseptic, tonic and other ayurvedic formulations. The essential oil also contains chavibetol, caryophyllene and methyl eugenol which are the potent source for preparation in ayurvedic medicine and herbal products. Cost of betelvine essential oil is 10$ per 5 mL. In spite of its great economical and medicinal importance betelvine is still neglected by the researchers for proper characterization and authentication for selection of elite landraces. Lack of awareness among people, use of same planting material for many generations, existing of many synonyms for a single landraces, no proper characterization of available landraces are some of the significant constraints for its commercialization. Our review endeavours a complete advance in the research on betelvine, existing lacunae for its proper characterization and commercial cultivation. It also attempts to provide a comprehensive account on biotechnological interventions made in betelvine aimed at complementing conventional programmes for improvement of this nutraceutically important cash crop. 展开更多
关键词 Betelvine(Piper betle L.) MEDICINAL USES Commercial CULTIVATION EUGENOL Bioactivity
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phytochemical investigation and in vitro antioxidant activity of an indigenous medicinal plant Alpinia nigra B.L.Burtt 被引量:2
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作者 Suprava Sahoo Goutam Ghosh +1 位作者 Debajyoti Das Sanghamitra Nayak 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第11期871-876,共6页
Objective:To investigate antioxidant potential of methanol extract of Alpinia nigra leaves.Methods:The study was done by using various in vitro methods such as 1,1-diphenyl-2-picrylhydrazyl(DPPH),2,2-azino-bis(3-ethyl... Objective:To investigate antioxidant potential of methanol extract of Alpinia nigra leaves.Methods:The study was done by using various in vitro methods such as 1,1-diphenyl-2-picrylhydrazyl(DPPH),2,2-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)(ABTS),nitric oxide and hydrogen peroxide radical scavenging assays.Phytochemical constituents,total phenolic content and total flavonoid content of the extract at different concentrations(10-500μg/mL)were determined.Results:Alpinia nigra leaves showed high free radical scavenging activity as evidenced by the low IG_(50)values in DPPH(64.51μg/mL),in ABTS(28.32μg/mL),in nitric oxide(80.02μg/mL)and in H_2O_2(77.45μg/mL)scavenging assays.Furthermore the TPC and TFC of the extract were found to be 69.25 mg gallic acid equivalent per gram of extract and 78.84 mg quercetin equivalent per gram of extract respectively.Conclusions:The results of present comprehensive analysis demonstrated that Alpinia nigra leaves possess high phenolic,flavonoid contents and potential antioxidant activity,and could be used as a viable source of natural antioxidants and might be exploited for functional foods and neutraceutical applications. 展开更多
关键词 ALPINIA nigra PHYTOCHEMICAL screening TPC TFC Antioxidant activity
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Flow of a biomagnetic viscoelastic fluid:application to estimation of blood flow in arteries during electromagnetic hyperthermia,a therapeutic procedure for cancer treatment 被引量:3
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作者 J.C.MISRA A.SINHA G.C.SHIT 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第11期1405-1420,共16页
The paper deals with the theoretical investigation of a fundamental problem of biomaguetic fluid flow through a porous medium subject to a magnetic field by using the principles of biomagnetic fluid dynamics (BFD). ... The paper deals with the theoretical investigation of a fundamental problem of biomaguetic fluid flow through a porous medium subject to a magnetic field by using the principles of biomagnetic fluid dynamics (BFD). The study pertains to a situation where magnetization of the fluid varies with temperature. The fluid is considered to be non-Newtonian, whose flow is governed by the equation of a second-grade viscoelastic fluid. The walls of the channel are assumed to be stretchable, where the surface velocity is proportional to the longitudinal distance from the origin of coordinates. The problem is first reduced to solving a system of coupled nonlinear differential equations involving seven parameters. Considering blood as a biomagnetic fluid and using the present analysis, an attempt is made to compute some parameters of the blood flow by developing a suitable numerical method and by devising an appropriate finite difference scheme. The computational results are presented in graphical form, and thereby some theoretical predictions are made with respect to the hemodynamical flow of the blood in a hyperthermal state under the action of a magnetic field. The results clearly indicate that the presence of a magnetic dipole bears the potential so as to affect the characteristics of the blood flow in arteries to a significant extent during the therapeutic procedure of electromagnetic hyperthermia. The study will attract the attention of clinicians, to whom the results would be useful in the treatment of cancer patients by the method of electromagnetic hyperthermia. 展开更多
关键词 biomagnetic fluid blood stretching walls porous medium electromagnetic hyperthermia
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Formulation and evaluation of novel stomach specific floating microspheres bearing famotidine for treatment of gastric ulcer and their radiographic study 被引量:2
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作者 Rishikesh Gupta Sunil Kumar Prajapati +1 位作者 Snigdha Pattnaik Peeyush Bhardwaj 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2014年第9期729-735,共7页
Objective:To develop and characterize multiple-unit-type oral floating microsphere of famotidine to prolong gastric residence time and to target stomach ulcer.Methods:The floating microspheres were prepared by modifie... Objective:To develop and characterize multiple-unit-type oral floating microsphere of famotidine to prolong gastric residence time and to target stomach ulcer.Methods:The floating microspheres were prepared by modified solvent evaporation method,Eudragil S-100 was used as polymer.Microspheres were characterized for the micromeritic properties,floating behavior,entrapment efficiency and scanning electron microscopy.The invitro release studies and floating behavior were studied in simulated gastric fluid at pH 1.2.Different drug release kinetics models were also applied for all the batches.Selected formulations were also subjected for X-ray radiographic study.Results:Floating microspheres were successfully prepared by modified solvent evaporation technique.Microspheres showed passable flow properties.The maximum yield of microspheres was up to(95.11±0.35)%.On the basis of optical microscopy particle size range was found to be ranging from(52.18±182.00) to(91.64±5.16) μm.Scanning electron microscopy showed their spherical size,perforated smooth surface and a cavity inside microspheres.Microspheres were capable to float up to 20 h in simulated gastric fluid.X-ray radiographic studies also proved its better retention in the stomach.Conclusions:On the basis of the results,such dosage forms may be a good candidate for stomach targeting and may be dispensed in hard gelatin capsules. 展开更多
关键词 FLOATING MICROSPHERES FAMOTIDINE FLOATING drug delivery STOMACH targeting
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Electroosmotic oscillatory flow of micropolar fluid in microchannels:application to dynamics of blood flow in microfluidic devices 被引量:2
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作者 J.C.MISRA S.CHANDRA +1 位作者 G.C.SHIT P.K.KUNDU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2014年第6期749-766,共18页
The electroosmotic flow of a micropolar fluid in a microchannel bounded by two parallel porous plates undergoing periodic vibration is studied. The equations for conservation of linear and angular momentums and Gauss... The electroosmotic flow of a micropolar fluid in a microchannel bounded by two parallel porous plates undergoing periodic vibration is studied. The equations for conservation of linear and angular momentums and Gauss's law of charge distribution are solved within the framework of the Debye-Hückel approximation. The fluid velocity and microrotation are assumed to depend linearly on the Reynolds number. The study shows that the amplitude of microrotation is highly sensitive to the changes in the magnitude of the suction velocity and the width of the microchannel. An increase in the micropolar parameter gives rise to a decrease in the amplitude of microrotation. Numerical estimates reveal that the microrotation of the suspended microelements in blood also plays an important role in controlling the electro-osmotically actuated flow dynamics in microbio-fluidic devices. 展开更多
关键词 blood flow electrohydrodynamic effect MICROFLUIDICS channel flow
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Numerical study of flow and heat transfer during oscillatory blood flow in diseased arteries in presence of magnetic fields 被引量:2
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作者 A.SINHA J.C.MISRA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第5期649-662,共14页
A problem motivated by the investigation of the heat and mass transfer in the unsteady magnetohydrodynamic (MHD) flow of blood through a vessel is solved numerically when the lumen of the vessel has turned into the ... A problem motivated by the investigation of the heat and mass transfer in the unsteady magnetohydrodynamic (MHD) flow of blood through a vessel is solved numerically when the lumen of the vessel has turned into the porous structure. The time-dependent permeability and the oscillatory suction velocity are considered. The computational results are presented graphically for the velocity, the temperature, and the concentration fields for various values of skin friction coefficients, Nusselt numbers, and Sherwood numbers. The study reveals that the flow is appreciably influenced by the presence of a magnetic field and also by the value of the Grashof number. 展开更多
关键词 mass transfer radiation suction velocity SKIN-FRICTION
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Microbial Recovery of Manganese using <i>Staphylococcus Epidermidis</i> 被引量:2
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作者 A.P. Das L.B. Sukla N. Pradhan 《International Journal of Nonferrous Metallurgy》 2012年第2期9-12,共4页
Manganese minerals are widely distributed throughout the globe. The most important industrial uses of Mn are in the manufacture of steel, non-ferrous alloys, carbon-zinc batteries and some chemical reagents. Microbial... Manganese minerals are widely distributed throughout the globe. The most important industrial uses of Mn are in the manufacture of steel, non-ferrous alloys, carbon-zinc batteries and some chemical reagents. Microbial recovery of manganese from low grade manganese ores using bioleaching was investigated in this paper. A bacterial strain, Staphylococcus epidermidis (MTCC-435) was collected from microbial type culture collection, IMTECH Chandigarh and used for the experiment. The experimental results for bioleaching with S. epidermidis showed that under pH 5.5, particle size –150 μm, pulp density 10%, temperature 35℃ and agitation 200 rpm, about 80% of Mn was recovered within 20 days of incubation. 展开更多
关键词 MANGANESE STAPHYLOCOCCUS EPIDERMIDIS BIOLEACHING
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Design and comparative in-vitro and in-vivo evaluation of starch-acrylate graft copolymer based salbutamol sulphate sustained release tablets
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作者 Pankaj Kumar Ashok Laxmanrao Ganure +2 位作者 Bharat Bhushan Subudhi Shubhanjali Shukla Pooja Upadhyay 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2015年第3期239-246,共8页
The present work deals with the development of controlled release tablets of salbutamol sulphate(SS)using graft copolymers of methyl methacrylate(St-g-PMMA and Ast-g-PMMA)on starch and acetylated starch.Formulations w... The present work deals with the development of controlled release tablets of salbutamol sulphate(SS)using graft copolymers of methyl methacrylate(St-g-PMMA and Ast-g-PMMA)on starch and acetylated starch.Formulations were evaluated for physical characteristics like hardness,friability,drug release,drug content and weight variations,which fulfilled all the official requirements of tablet dosage form.The release rates from formulated matrix tablets were studied at SGF(pH 1.2)followed by SIF(pH 6.8).Drug release from the graft copolymer based tablets was found to be sustained upto the 14 h with>75%drug release.The in-vitro release study showed that the graft copolymer based matrix formulations(F3&F4)exhibited highest correlation value(r2)for higuchi kinetic model and Korsmeyer's model with n values between 0.61 and 0.67 proved that release mechanisms were governed by both diffusion and erosion mechanism.There was no significant difference in the pharmacokinetic parameters(tmax,Cmax,AUC,Ke,and t1/2)of the graft copolymers matrices and HPMC K100M matrix tablets,indicating their comparable sustained release effect.The potential of graft copolymers to sustain the drug release is well supported by in-vivo pharmacokinetic studies and their adequate physicochemical properties make them promising excipients for controlled drug delivery system. 展开更多
关键词 Salbutamol sulphate Methyl methacrylate Graft copolymers Acetylated starch Korsmeyer's model In vitro and in vivo
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A Parametric Approach to Non-Convex Optimal Control Problem
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作者 S. Mishra J. R. Nayak 《American Journal of Operations Research》 2014年第2期53-58,共6页
In this paper we have considered a non convex optimal control problem and presented the weak, strong and converse duality theorems. The optimality conditions and duality theorems for fractional generalized minimax pro... In this paper we have considered a non convex optimal control problem and presented the weak, strong and converse duality theorems. The optimality conditions and duality theorems for fractional generalized minimax programming problem are established. With a parametric approach, the functions are assumed to be pseudo-invex and v-invex. 展开更多
关键词 Non CONVEX PROGRAMMING Pseudo-Invex FUNCTIONS V-Invex FUNCTIONS Fractional MINIMAX PROGRAMMING
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Performance Analysis of 5 G Wireless Hybrid Precoding Using Evolutionary Algorithms
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作者 Madhusmita Sahoo Harish Kumar Sahoo 《Journal of Bionic Engineering》 SCIE EI CSCD 2023年第5期2317-2330,共14页
Emerging 5G communication solutions utilize the millimeter wave(mmWave)band to alleviate the spectrum deficit.In the mmWave range,Multiple Input Multiple Output(MIMO)technologies support a large number of simultaneous... Emerging 5G communication solutions utilize the millimeter wave(mmWave)band to alleviate the spectrum deficit.In the mmWave range,Multiple Input Multiple Output(MIMO)technologies support a large number of simultaneous users.In mmWave MIMO wireless systems,hybrid analog/digital precoding topologies provide a reduced complexity substitute for digital precoding.Bit Error Rate(BER)and Spectral efficiency performances can be improved by hybrid Minimum Mean Square Error(MMSE)precoding,but the computation involves matrix inversion process.The number of antennas at the broadcasting and receiving ends is quite large for mm-wave MIMO systems,thus computing the inverse of a matrix of such high dimension may not be practically feasible.Due to the need for matrix inversion and known candidate matrices,the classic Orthogonal Matching Pursuit(OMP)approach will be more complicated.The novelty of research presented in this manuscript is to create a hybrid precoder for mmWave communication systems using metaheuristic algorithms that do not require matrix inversion processing.The metaheuristic approach has not employed much in the formulation of a precoder in wireless systems.Five distinct evolutionary algorithms,such as Harris–Hawks Optimization(HHO),Runge–Kutta Optimization(RUN),Slime Mould Algorithm(SMA),Hunger Game Search(HGS)Algorithm and Aquila Optimizer(AO)are considered to design optimal hybrid precoder for downlink transmission and their performances are tested under similar practical conditions.According to simulation studies,the RUN-based precoder performs better than the conventional algorithms and other nature-inspired algorithms based precoding in terms of spectral efficiency and BER. 展开更多
关键词 Millimeter wave Hybrid precoding MIMO HHO HGS RUN SMA.AO
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Revisiting the role of mesenchymal stem cells in tuberculosis and other infectious diseases
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作者 Annu Devi Isha Pahuja +5 位作者 Shashi Prakash Singh Akanksha Verma Debapriya Bhattacharya Ashima Bhaskar Ved Prakash Dwivedi Gobardhan Das 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2023年第6期600-612,共13页
Mesenchymal stem cells(MsCs)play diverse roles ranging from regeneration and wound healing to immune signaling.Recent investigations have indicated the crucial role of these multipotent stem cells in regulating variou... Mesenchymal stem cells(MsCs)play diverse roles ranging from regeneration and wound healing to immune signaling.Recent investigations have indicated the crucial role of these multipotent stem cells in regulating various aspects of the immune system.MsCs express unique signaling molecules and secrete various soluble factors that play critical roles in modulating and shaping immune responses,and in some other cases,MSCs can also exert direct antimicrobial effects,thereby helping with the eradication of invading organisms.Recently,it has been demonstrated that MSCs are recruited at the periphery of the granuloma containing Mycobacterium tuberculosis and exert"Janus"-like functions by harboring pathogens and mediating host protective immune responses.This leads to the establishment of a dynamic balance between the host and the pathogen.MsCs function through various immunomodulatory factors such as nitric oxide(NO),IDO,and immunosuppressive cytokines.Recently,our group has shown that M.tb uses MSCs as a niche to evade host protective immune surveillance mechanisms and establish dormancy.MSCs also express a large number of ABC efflux pumps;therefore,dormant M.tb residing in MSCs are exposed to a suboptimal dose of drugs.Therefore,it is highly likely that drug resistance is coupled with dormancy and originates within MSCs.In this review,we discussed various immunomodulatory properties of MsCs,their interactions with important immune cells,and soluble factors.We also discussed the possible roles of MsCs in the outcome of multiple infections and in shaping the immune system,which may provide insight into therapeutic approaches using these cells in different infection models. 展开更多
关键词 Mesenchymal Stem Cells(MsCs) MACROPHAGES TUBERCULOSIS Infectious Diseases T cells IMMUNOMODULATION Immunotherapy.
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Study of Structural and Electrical Properties of a New Type of Complex Tungsten Bronze Electroceramics;Li<sub>2</sub>Pb<sub>2</sub>Y<sub>2</sub>W<sub>2</sub>Ti<sub>4</sub>V<sub>4</sub>O<sub>30</sub>
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作者 Piyush R. Das B. Pati +1 位作者 B.C. Sutar R.N.P. Choudhury 《Journal of Modern Physics》 2012年第8期870-880,共11页
A polycrystalline ceramic, a new type of complex tungsten bronze type structure, having a general formula Li2Pb2Y2W2Ti4V4O30 has been prepared relatively at low temperature using a mixedoxide technique after optimizin... A polycrystalline ceramic, a new type of complex tungsten bronze type structure, having a general formula Li2Pb2Y2W2Ti4V4O30 has been prepared relatively at low temperature using a mixedoxide technique after optimizing the calcination conditions on the basis of thermal analysis. The material has been characterized by different experimental techniques. The formation of the material under the reported conditions has been confirmed by an X-ray diffraction technique. A preliminary structural analysis of the material showed the formation of single phase compound in an orthorhombic crystal structure at room temperature. Studies of dielectric properties (εr, tanδ ) of the above compound as a function of temperature at different frequencies exhibit a ferroelectric phase transition of diffuse type. The electrical properties of the material have been studied using ac impedance spectroscopy technique. Detailed studies of impedance and related parameters exhibit that the electrical properties of the material are strongly dependent on temperature, and bear a good correlation with its microstructure. The temperature dependence of electrical relaxation phenomenon in the material has been observed. The bulk resistance, evaluated from complex impedance spectra, is found to decrease with rise in temperature, exhibiting a typical negative temperature co-efficient of resistance (NTCR) – type behavior similar to that of semiconductors. A small contribution of grain boundary effect was also observed. The complex electric modulus analysis indicates the possibility of hopping conduction mechanism in the system with non-exponential type of conductivity relaxation. The ac conductivity spectra exhibit a typical signature of an ionic conducting system, and are found to obey Jonscher’s universal power law. 展开更多
关键词 ELECTROCERAMICS Impedance ANALYSIS Bulk Resistance Electric MODULUS ANALYSIS
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A Hybrid Time Frequency Response and Fuzzy Decision Tree for Non-stationary Signal Analysis and Pattern Recognition 被引量:3
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作者 N.R.Nayak P.K.Dash R.Bisoi 《International Journal of Automation and computing》 EI CSCD 2019年第3期398-412,共15页
A Fourier kernel based time-frequency transform is a proven candidate for non-stationary signal analysis and pattern recognition because of its ability to predict time localized spectrum and global phase reference cha... A Fourier kernel based time-frequency transform is a proven candidate for non-stationary signal analysis and pattern recognition because of its ability to predict time localized spectrum and global phase reference characteristics.However,it suffers from heavy computational overhead and large execution time.The paper,therefore,uses a novel fast discrete sparse S-transform(SST)suitable for extracting time frequency response to monitor non-stationary signal parameters,which can be ultimately used for disturbance detection,and their pattern classification.From the sparse S-transform matrix,some relevant features have been extracted which are used to distinguish among different non-stationary signals by a fuzzy decision tree based classifier.This algorithm is robust under noisy conditions.Various power quality as well as chirp signals have been simulated and tested with the proposed technique in noisy conditions as well.Some real time mechanical faulty signals have been collected to demonstrate the efficiency of the proposed algorithm.All the simulation results imply that the proposed technique is very much efficient. 展开更多
关键词 NON-STATIONARY signals sparse S-transform(SST) SCALING method fuzzy DECISION tree pattern classification
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Electro-osmotic flow of a second-grade fluid in a porous microchannel subject to an AC electric field 被引量:2
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作者 MISRA J. C. CHANDRA S. 《Journal of Hydrodynamics》 SCIE EI CSCD 2013年第2期309-316,共8页
Studies on electro-osmotic flows of various types of fluids in microchannel are of great importance owing to their multifold applications in the transport of liquids, particularly when the ionized liquid flows with re... Studies on electro-osmotic flows of various types of fluids in microchannel are of great importance owing to their multifold applications in the transport of liquids, particularly when the ionized liquid flows with respect to a charged surface in the presence of an external electric field. In the case of viscoelastic fluids, the volumetric flow rate differs significantly from that of Newtonian fluids, even when the flow takes place under the same pressure gradient and the same electric field. With this end in view, this paper is devoted to a study concerning the flow pattern of an electro-osmotic flow in a porous microchannel, which is under the action of an alternating electric field. The influence of various rheological and electro-osmotic parameters, e.g., the Reynolds number, Debye-Huckel parameter, shape factor and fluid viscoelasticity on the kinematics of the fluid, has been investigated for a secondgrade viscoelastic fluid. The problem is first treated by using analytical methods, but the quantitative estimates are obtained numerically with the help of the software MATHEMATICA. The results presented here are applicable to the cases where the channel height is much greater than the thickness of the electrical double layer comprising the Stern and diffuse layers. The study reveals that a larger value of the Debye-Huckel parameter creates sharper profile near the wall and also that the velocity of electro-osmotic flow increases as the permeability of the porous microchannel is enhanced. The study further shows that the electro-osmotic flow dominates at lower values of Reynolds number. The results presented here will be quite useful to validate the observations of experimental investigations on the characteristics of electro-osmotic flows and also the results of complex numerical models that are necessary to deal with more realistic situations, where electro-osmotic flows come into the picture, as in blood flow in the micro-circulatory system subject to an electric field. 展开更多
关键词 electrical double layer Debye length second-grade fluid Ionic energy
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Application of quasi-oppositional symbiotic organisms search based extreme learning machine for stock market prediction
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作者 Smita Rath Binod Kumar Sahu Manoj Ranjan Nayak 《International Journal of Intelligent Computing and Cybernetics》 EI 2019年第2期175-193,共19页
Purpose–Forecasting of stock indices is a challenging issue because stock data are dynamic,non-linear and uncertain in nature.Selection of an accurate forecasting model is very much essential to predict the next-day ... Purpose–Forecasting of stock indices is a challenging issue because stock data are dynamic,non-linear and uncertain in nature.Selection of an accurate forecasting model is very much essential to predict the next-day closing prices of the stock indices.The purpose of this paper is to develop an efficient and accurate forecasting model to predict the next-day closing prices of seven stock indices.Design/methodology/approach–A novel strategy called quasi-oppositional symbiotic organisms search-based extreme learning machine(QSOS-ELM)is proposed to forecast the next-day closing prices effectively.Accuracy in the prediction of closing price depends on output weights which are dependent on input weights and biases.This paper mainly deals with the optimal design of input weights and biases of the ELM prediction model using QSOS and SOS optimization algorithms.Findings–Simulation is carried out on seven stock indices,and performance analysis of QSOS-ELM and SOS-ELM prediction models is done by taking various statistical measures such as mean square error,mean absolute percentage error,accuracy and paired sample t-test.Comparative performance analysis reveals that the QSOS-ELM model outperforms the SOS-ELM model in predicting the next-day closing prices more accurately for all the seven stock indices under study.Originality/value–The QSOS-ELM prediction model and SOS-ELM are developed for the first time to predict the next-day closing prices of various stock indices.The paired t-test is also carried out for the first time in literature to hypothetically prove that there is a zero mean difference between the predicted and actual closing prices. 展开更多
关键词 Extreme learning machine Symbiotic organisms search Quasi-oppositional-based learning Paired sample t-test
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Dielectric response and pyroelectric properties of lead-free ferroelectric Ba_(3)(VO_(4))_(2)
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作者 Biswajit Pati R.N.P.Choudhary +1 位作者 Piyush R.Das B.C.Sutar 《Journal of Advanced Dielectrics》 CAS 2015年第1期43-49,共7页
The current paper presents results of dielectric response,pyroelectric behavior and conductivity study of lead-free ferroelectric barium orthovanadate(Ba_(3)(VO_(4))_(2)or Ba_(3)V_(2)O_(8))ceramic,for a wide range of ... The current paper presents results of dielectric response,pyroelectric behavior and conductivity study of lead-free ferroelectric barium orthovanadate(Ba_(3)(VO_(4))_(2)or Ba_(3)V_(2)O_(8))ceramic,for a wide range of temperature and frequency.An X-ray diffraction study suggests the formation of a single-phase compound in trigonal crystal system.The SEM micrograph of gold-coated pellet sample shows well-defined and homogeneous morphology.Detailed studies of dielectric parameters(ε_(r)and tanδ)of the compound as a function of temperature and frequency reveal their independence over a wide range of temperature and frequency.The nature of Polarization versus electric field(P-E)hysteresis loop of Ba_(3)V_(2)O_(8)at room temperature suggests its ferroelectric nature.The temperature dependence of pyroelectric coefficient and figure of merits of the sample support its dielectric response.The nature of variation of dc conductivity with temperature confirms the Arrhenius and negative temperature coefficient of resistance(NTCR)behavior of the material. 展开更多
关键词 X-ray diffraction Palmierite structure dielectric properties pyroelectric properties
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Non-communicable disease care and physical activity promotion in India:analysis of recent policies,guidelines and workplans
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作者 Satyajit Mohanty Epari Venkatarao Sandul Yasobant 《Family Medicine and Community Health》 2020年第2期1-9,共9页
Burden statements on non-communicable diseases(NCDs)across the globe suggest that they pose a constant threat to human development.There are two different types of NCD interventions:population-based interventions addr... Burden statements on non-communicable diseases(NCDs)across the globe suggest that they pose a constant threat to human development.There are two different types of NCD interventions:population-based interventions addressing NCD risk factors and individual-based interventions addressing NCDs in the primary care setting.Most of the individual-based interventions are based on NCD-care models,as opposed to population-based interventions targeting risk factors through independent vertical programmes.We explored the relevant Indian policy documents including the recent National Health Policy 2017,to get an overview of the Indian NCD-care model and to find out how physical activity(PA)promotion stands in the year 2019 in the current policy documents on NCDs.We conducted a review with two perspectives;first to capture the NCD-care models and second to document the PA promotion and its integration in the current NCD-care model specific to the Indian context.Indian NCD programme is an evolving healthcare programme with a definite NCD-care model,where the individual-based and population-based care are thoroughly linked.Despite having good NCD-care policy and methodical planning,PA promotion seems to be lacking in the policy perspective and currently physical inactivity as a risk factor is not considered seriously.The structure of the NCD-care model should be detailed and strengthened by incorporating lessons from other successful NCD models from across the globe.Indian NCD model must provide sufficient scope of interfacing individual care to that of population-based risk factor strategies like physical activity promotion. 展开更多
关键词 PROMOTION INDIAN policy
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Adaptive fractional integral terminal sliding mode power control of UPFC in DFIG wind farm penetrated multimachine power system
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作者 P.K.Dash R.K.Patnaik S.P.Mishra 《Protection and Control of Modern Power Systems》 2018年第1期79-92,共14页
With an aim to improve the transient stability of a DFIG wind farm penetrated multimachine power system(MPN),an adaptive fractional integral terminal sliding mode power control(AFITSMPC)strategy has been proposed for ... With an aim to improve the transient stability of a DFIG wind farm penetrated multimachine power system(MPN),an adaptive fractional integral terminal sliding mode power control(AFITSMPC)strategy has been proposed for the unified power flow controller(UPFC),which is compensating the MPN.The proposed AFITSMPC controls the dq-axis series injected voltage,which controls the admittance model(AM)of the UPFC.As a result the power output of the DFIG stabilizes which helps in maintaining the equilibrium between the electrical and mechanical power of the nearby generators.Subsequently the rotor angular deviation of the respective generators gets recovered,which significantly stabilizes the MPN.The proposed AFITSMPC for the admittance model of the UPFC has been validated in a DFIG wind farm penetrated 2 area 4 machine power system in the MATLAB environment.The robustness and efficacy of the proposed control strategy of the UPFC,in contrast to the conventional PI control is vindicated under a number of intrinsic operating conditions,and the results analyzed are satisfactory. 展开更多
关键词 Adaptive fractional integral terminal sliding mode power control Doubly fed induction generator Multimachine power network Unified power flow controller
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A fast time-frequency response based differential spectral energy protection of AC microgrids including fault location
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作者 O.Dharmapandit R.K.Patnaik P.K.Dash 《Protection and Control of Modern Power Systems》 2017年第1期331-358,共28页
This paper proposes a pattern recognition based differential spectral energy protection scheme for ac microgrids using a Fourier kernel based fast sparse time-frequency representation(SST or simply the sparse S-Transf... This paper proposes a pattern recognition based differential spectral energy protection scheme for ac microgrids using a Fourier kernel based fast sparse time-frequency representation(SST or simply the sparse S-Transform).The average and differential current components are passed through a change detection filter,which senses the instant of fault inception and registers a change detection point(CDP).Subsequently,if CDP is registered for one or more phases,then half cycle data samples of the average and differential currents on either side of the CDP are passed through the proposed SST technique,which generates their respective spectral energies and a simple comparison between them detects the occurrence and type of the fault.The SST technique is also used to provide voltage and current phasors and the frequency during faults which is further utilized to estimate the fault location.The proposed technique as compared to conventional differential current protection scheme is quicker in fault detection and classification,which is least effected from bias setting,has a faster relay trip response(less than one cycle from fault incipient)and a better accuracy in fault location.The significance and accuracy of the proposed scheme have been verified extensively for faults in a standard microgrid system,subjected to a large number of operating conditions and the outputs vindicate it to be a potential candidate for real time applications. 展开更多
关键词 MICROGRID Differential spectral energy protection Time-frequency representation Fault classification Fault location
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