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Mill tailings based composites as paste backfill in mines of U-bearing dolomitic limestone ore

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第2期10卷 310-322页

作者： sandeep Panchal Debasis Deb T.Sreenivas Department of Mining Engineering Indian Institute of Technology Mineral Processing Division Bhabha Atomic Research Centre

This paper elaborates on the development of paste backfill using mill tailings generated during the processing of a uranium ore deposit hosted in dolomitic limestone. The tailings have been characterized in terms of the physical, chemical and mineralogical properties. Time-dependent rheological behaviors and geotechnical properties of cemented paste backfill(CPB) are also determined. The studies show that the mill tailing has the potential to form paste and the CPB has adequate strength to provide support to mine pillars, roofs, and walls.

关键词： Mining engineering Uranium ore deposit Tailings Cemented paste backfill(CPB) Rheology Compressive strength

Climatic periodicities recorded in lake sediment magnetic susceptibility data:Further evidence for solar forcing on Indian summer monsoon

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Geoscience Frontiers 2017年第6期8卷 1349-1355页

作者： Anish Kumar Warrier Kizhur sandeep Rajasekharaiah Shankar Department of Marine Geology Mangalore UniversityMangalagangotri 574199KarnatakaIndia Department of Civil Engineering Manipal Institute of TechnologyManipal UniversityManipal 576104KarnatakaIndia Department of Geology School of Earth Science SystemsCentral University of KeralaTejaswini HillsPeriye(P.O.)KasaragodKerala 671 123India

The Indian summer monsoon exhibits considerable spatio-temporal *** is therefore important to understand its dynamics and the inherent *** this study,we have performed spectral and wavelet analyses of magnetic susceptibility data for sediments from Thimmannanayakanakere(TK)-a small lake in southern *** main objective of this investigation is to identify and explain the possible origin of the prominent periodicities present in the magnetic susceptibility *** periodicities in the TK χ_(lf)data are centered at 906,232,147,128,96,61,54 and 44 years,which might have a solar *** wavelet power spectrum of the raw and detrended χ_(lf)data confirms the findings of spectral analysis and also provides temporal variations of the significant cyclicities during the past3700 *** *** correlation is documented between sunspot activity and TK xif data;crossspectral analysis of the reconstructed sunspot data and TK xif data suggest that there is a strong coherence between the two datasets as significant periodicities are documented in *** is a good match between the TK xif and the reconstructed total solar irradiance data for the past 1200 ***,an out-of-phase relationship is documented at certain time-intervals,which may be attributed to uncertainties in the age-depth *** results obtained from this study show that solar variations are the main controlling factor of the southwest monsoon and,like other archives from different regions in India,the TK lake sediments have also recorded these solar signatures.

关键词： Spectral analysis Periodicity Paleorainfall Lake sediments Magnetic susceptibility Southern India

Geometry Design and Tooth Contact Analysis of Crossed Beveloid Gears for Marine Transmissions

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Chinese Journal of Mechanical Engineering 2012年第2期25卷 328-337页

作者： ZHU Caichao SONG Chaosheng LIM Teik Chin VIJAYAKAR sandeep State Key Laboratory of Mechanical Transmission Chongqing UniversityChongqing 400030China School of Dynamics Systems at University of Cincinnati CincinnatiOhio 45221USA Advanced Numerical Solutions 3956 Brown Park DriveSuite BHilliardOhio 43026USA

Beveloid gears,also known as conical gears,gain more and more importance in industry practice due to their abilities for power transmission between parallel,intersected and crossed ***,this type of gearing with crossed axes has no common plane of action which results in a point contact and low tooth ***,a geometry design approach assuming line contact is developed to analyze the tooth engagement process of crossed beveloid gears with small shaft angle for marine transmission *** loaded gear tooth contact behavior is simulated by applying a quasi-static analysis to study the effects of gearing parameters on mesh *** the proposed method,a series of sensitivity analyses to examine the effects of critical gearing parameters such as shaft angle,cone angle,helix angle and profile-shift coefficient on the theoretical gear mesh is *** parametric analysis of pitch cone design shows that the dominant design parameters represented by the angle between the first principle directions（FPD） and normal angular factor are more sensitive to the shaft and cone angles than they are to the helix *** theoretical contact path is highly sensitive to the profile-shift coefficient,which is determined from the theoretical tooth contact *** FPD angle is found to change the distribution of contact pattern,contact pressure and root stress as well as the translational transmission error and the variation of the mesh stiffness *** contact pattern is clearly different between the drive and coast sides due to different designed FPD ***,a practical experimental setup for marine transmission is performed and tooth bearing test is conducted to demonstrate the proposed design *** experimental result compared well with the *** of this study yield a better understanding of the geometry design and loaded gear mesh characteristics for crossed beveloid gears used in marine trans

关键词： beveloid gears loaded tooth contact analysis crossed axes marine transmission

Advanced endoscopic imaging in Barrett's oesophagus:A review on current practice

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World Journal of Gastroenterology 2011年第38期17卷 4271-4276页

作者： Rajvinder Singh SweeLin Chen Yi Mei sandeep Sethi Gastroenterology Unit Department of MedicineLyell McEwin Hospital/University of Adelaide

Over the last few years,improvements in endoscopic imaging technology have enabled identification of dysplasia and early cancer in Barrett's *** techniques should exhibit high sensitivities and specificities and have good interobserver *** should also be affordable and easily applicable to the community ***,these modalities must exhibit the capability of imaging wide areas in real time whilst enabling the endoscopist to specifically target abnormal *** review will specifically focus on some of the novel endoscopic imaging modalities currently available in routine practice which includes chromoendoscopy,autofluorescence imaging and narrow band imaging.

关键词： Autofluorescence imaging Barrett's oesoph-agus Chromoendoscopy High magnifcation endoscopy Narrow band imaging

Ordering Cost Depletion in Inventory Policy with Imperfect Products and Backorder Rebate

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Computers, Materials & Continua 2021年第3期66卷 2343-2357页

作者： sandeep Kumar Teekam Singh Kamaleldin Abodayeh Wasfi Shatanawi Department of Mathematics Graphic Era Hill UniversityDehradun248002India Department of Mathematics Graphic Era Deemed UniversityDehradun248002India Department of Mathematics and General Sciences Prince Sultan UniversityRiyadh11586Saudi Arabia China Medical University Hospital China Medical UniversityTaichung40402Taiwan Department of Mathematics Hashemite UniversityZarqa13133Jordan

This study presents an inventory model for imperfect products with depletion in ordering costs and constant lead time where the price discount in the backorder is *** imperfect products are refused or modified or if they reached to the customer,returned and thus some extra costs are *** some of the researchers explicitly present on the significant association between size of lot and quality *** practical situations,the unsatisfied demands increase the period of lead time and decrease the *** control customers'problems and losses,the supplier provides a price discount in backorders during ***,an order’s policies may result in including some imperfect products in arrival lots.A discount on price may be offered by the supplier on the out-of-stock products to manage the backorder *** study aims to develop a model with imperfect products by permitting the price discount in backorders,and the cost of ordering is considered a decision ***,it is assumed that the demand for lead time is followed by a normal distribution and then stops it and assumed that the first two moments of demand for lead time are ***,the minimax distribution method is used to solve this model,and a separate algorithm is *** this study,two models are discussed with and without a normally distributed rate of *** current study verified with the help of some numerical examples over various model parameters.

关键词： Inventory ordering cost imperfect product lead time backorder

Model based odia numeral recognition using fuzzy aggregated features

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Frontiers of Computer Science 2014年第6期8卷 916-922页

作者： Tusar Kanti MISHRA Banshidhar MAJHI Pankaj K SA sandeep PANDA Department of Computer Science and Engineering National Institute of Technology Rourkela 769008 India

In this paper, an efficient scheme for recognition of handwritten Odia numerals using hidden markov model （HMM） has been proposed. Three different feature vectors for each of the numeral is generated through a polygonal approximation of object contour. Subsequently, aggregated feature vector for each numeral is derived from these three primary feature vectors using a fuzzy inference system. The final feature vector is divided into three levels and interpreted as three different states for HMM. Ten different three-state ergodic hidden markov models （HMMs） are thus constructed corresponding to ten numeral classes and parameters are calculated from these models. For the recognition of a probe numeral, its log-likelihood against these models are computed to decide its class label. The proposed scheme is implemented on a dataset of 2500 handwritten samples and a recognition accuracy of 96.3% has been achieved. The scheme is compared with other competent schemes.

关键词： handwritten character recognition HMM pattern recognition Odia numeral OCR

Structural,electronic,magnetic and optical properties of neodymium chalcogenides using LSDA+U method

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Journal of Semiconductors 2012年第8期33卷 9-14页

作者： A Shankar D P Rai sandeep R K Thapa Condensed Matter Theory Group Department of PhysicsMizoram UniversityAizawlMizoram-796004India

We have studied the electronic, magnetic and optical properties of neodymium chalcogenides by performing LSDA＋ U and full potential linearized augmented plane wave （FP-LAPW） method. The electronic structure calculation shows that the electronic states in Nd-chalcogenides were mainly contributed by Nd-4f electrons near Fermi energy and 3p, 4p and 5p state electrons of X （S, Se and Te）, respectively. We have also studied the absorption of light via the imaginary parts of the dielectric function of Nd-chalcogenides.

关键词： DFT DOS magnetic moment U

Low power digitally controlled oscillator designs with a novel 3-transistor XNOR gate

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Journal of Semiconductors 2012年第3期33卷 52-59页

作者： Manoj Kumar sandeep K.Arya Sujata Pandey Department of Electronics&Communication Engineering Guru Jambheshwar University of Science&Technology Amity University

Digital controlled oscillators（DCOs） are the core of all digital phase locked loop（ADPLL） circuits. Here,DCO structures with reduced hardware and power consumption having full digital control have been proposed. Three different DCO architectures have been proposed based on ring based ***,four and five bit controlled DCO with NMOS,PMOS and NMOS PMOS transistor switching networks are presented.A three-transistor XNOR gate has been used as the inverter which is used as the delay *** has been controlled digitally with a switch network of NMOS and PMOS *** three bit DCO with one NMOS network shows frequency variations of 1.6141-1.8790 GHz with power consumption variations 251.9224-276.8591μW. The four bit DCO with one NMOS network shows frequency variation of 1.6229-1.8868 GHz with varying power consumption of 251.9225-278.0740μW.A six bit DCO with one NMOS switching network gave an output frequency of 1.7237-1.8962 GHz with power consumption of 251.928-278.998μ*** frequency and power consumption results for 4 6 bit DCO circuits with one PMOS and NMOS PMOS switching network have also been *** phase noise parameter with an offset frequency of 1 MHz has also been reported for the proposed *** with earlier reported circuits have been made and the present approach shows advantages over previous circuits.

关键词： digital control oscillator delay cell power consumption voltage controlled oscillators

Synthesis,and measurement of structural and magnetic properties,of La_(1-x)Na_xFeO_3 (0.0≤x≤0.3) perovskite oxides

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Journal of Rare Earths 2009年第5期27卷 691-697页

作者： Manjunath B.Bellakki Venkatesan Manivannan Patrick McCurdy sandeep Kohli Department of Mechanical Engineering Colorado State University Department of Chemistry Colorado State University

Polycrystalline La1-xNaxFeO3 (0.0≤x≤0.3) solid solutions were synthesized by a solution combustion method using glycine as a fuel. The combustion synthesized compounds were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), diffused reflectance (DR) in the UV-vis, and magnetic measurements. The crystal structure examined by X-ray powder diffraction indicated that the samples were single phase and crystallized in an orthorhombic (space group, Pbnm no.62) structure. The parent and sodium-substituted compounds showed canted anti-ferromagnetic behavior associated with an increase in magnetic moment as Na content increased. The changes in magnetic properties of the materials were correlated to the changes in structural features, as shown by Rietveld structural refinement of the materials.

关键词： oxides combustion synthesis X-ray diffraction antiferromagnetic rare earths