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A PRoCESS FoR SoLVING A FEW EXTREME EIGENPAIRS oF LARGE SPARSE PoSITIVE DEFINITE GENERALIZED EIGENVALUE PRoBLEM

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Journal of Computational Mathematics 2000年第4期18卷 387-402页

作者： Chong-hua Yu o.Axelsson Department of Mathematics Fudan UniversityShanghai 200433China Faculty of Mathematics and Informatics University of Nijmegen6525 ED NijmegenThe Netherlands

In this paper, an algorithm for computing some of the largest (smallest) generalized eigenvalues with corresponding eigenvectors of a sparse symmetric positive definite matrix pencil is presented. The algorithm uses an iteration function and inverse power iteration process to get the largest one first, then executes m - 1 Lanczos-like steps to get initial approximations of the next m - 1 ones, without computing any Ritz pair, for which a procedure combining Rayleigh quotient iteration with shifted inverse power iteration is used to obtain more accurate eigenvalues and eigenvectors. This algorithm keep the advantages of preserving sparsity of the original matrices as in Lanczos method and RQI and converges with a higher rate than the method described in [12] and provides a simple technique to compute initial approximate pairs which are guaranteed to converge to the wanted m largest eigenpairs using RQL. In addition, it avoids some of the disadvantages of Lanczos and RQI, for solving extreme eigenproblems. When symmetric positive definite lira ear systems must be solved in the process, an algebraic multilevel iteration method (AMLI) is: applied. The algorithm is fully parallelizable. [ABSTRACT FRoM AUTHoR]

关键词： eigenvalue sparse problem

Valorization of Tree Bark-Derived Suberin in Applications for the Bio-Based Composites Industry–A Recent Review

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Journal of Renewable Materials 2024年第6期12卷 1029-1042页

作者： Aleksandra Jeżo Institute of Wood Sciences and Furniture SGGWNowoursynowska St.159Warsaw02-776Poland

Bark extracts are sustainable sources of biopolymers and hold great promise for replacing fossil fuel-based polymers,for example,in wood-based *** addition to primary and secondary metabolites,tree bark also contains suberin,which plays a major role in protecting the tree from environmental *** is a natural aliphatic-aromatic cross-linked polyester present in the cell walls of both normal and damaged external tissues,the main component of which are long-chain aliphatic *** main role as a plant ingredient is to protect against microbiological factors and water *** of the most important suberin monomers are suberin fatty acids,known for their hydrophobic and barrier ***,due to the diverse chemical composition of suberin,it is an attractive alternative to hydrocarbon-based *** its potential is recognized,it is not widely used in biocomposites technology,including wood-based composites and the polymer *** article will discuss the current knowledge about the potential of suberin and its components in biocomposites technology,which will include surface finishes,composite adhesives and polymer blends.

关键词： Suberin suberinic acids wood composites biocomposites biopolyester

Improving fluidization behavior of cohesive Ca(oH)2 adsorbent using hydrophilic silica nanoparticles:Parametric investigation

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Particuology 2018年第5期16卷 52-61页

作者： o.Amjadi M.Tahmasebpoor Department of Chemical and Petroleum Engineering University of TabrizTabrizP.O.Box 51666-16471Iran

Hydrophilic silica nanoparticles were used to enhance the fluidization behavior of Ca(oH)2 powder and its Co2 *** strong electrostatic forces were decreased by fluidizing adsorbents modified by hydrophilic Sio2 in the presence of alcohol vapors.A Taguchi experimental design was used to identify the optimal characteristic parameters of the modified adsorbents to improve their *** parameters,including Sio2mass percentage,type of alcohol,sieved size of Sio2,and sieved size of Ca(oH)2 particles,were selected for conducting experiments in a fluidized *** of variance showed that sieved size and mass percentage of Sio2 nanoparticles (accounting for 73.88% and 19.01% of the total contributions,respectively)were the most significant parameters determining fluidization quality of the modified *** experiments confirmed the effectiveness of these two parameters. Based on bed expansion results,fluidization of Ca(oH)2 modified by hydrophilic silica nanoparticles in the presence of alcohols was considerably better than that modified by hydrophobic ***2 adsorption tests,which were carried out by measuring the pH variation of pure water during adsorption, revealed that improved Ca(oH)2 fluidization enhanced the carbonation reaction.

关键词： Fluidization Ca(oH)2 Sihca nanoparticles Carbon dioxide adsorption Taguchi method

Redox regulation of mammalian sperm capacitation

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Asian Journal of Andrology 2015年第4期17卷 583-590页

作者： Cristian o'Flaherty Urology Research Laboratory Surgery Department (Urology Division) Faculty of Medicine McGill University Montreal Quebec Canada The Research Institute McGillUniversity Health Centre Montreal Quebec Canada.

Capacitation is a series of morphological and metabolic changes necessary for the spermatozoon to achieve fertilizing ability. one of the earlier happenings during mammalian sperm capacitation is the production of reactive oxygen species （RoS） that will trigger and regulate a series of events including protein phosphorylation, in a time-dependent fashion. The identity of the sperm oxidase responsible for the production of RoS involved in capacitation is still elusive, and several candidates are discussed in this review. Interestingly, RoS-induced RoS formation has been described during human sperm capacitation. Redox signaling during capacitation is associated with changes in thiol groups of proteins located on the plasma membrane and subcellular compartments of the spermatozoon. Both, oxidation of thiols forming disulfide bridges and the increase on thiol content are necessary to regulate different sperm proteins associated with capacitation. Reducing equivalents such as NADH and NADPH are necessary to support capacitation in many species including humans. Lactate dehydrogenase, glucose-6-phospohate dehydrogenase, and isocitrate dehydrogenase are responsible in supplying NAD （P） H for sperm capacitation. Peroxiredoxins （PRDXs） are newly described enzymes with antioxidant properties that can protect mammalian spermatozoa; however, they are also candidates for assuring the regulation of redox signaling required for sperm capacitation. The dysregulation of PRDXs and of enzymes needed for their reactivation such as thioredoxin/thioredoxin reductase system and glutathione-S-transferases impairs sperm motility, capacitation, and promotes DNA damage in spermatozoa leading to male infertility.

关键词： dehydrogenases oxidases peroxiredoxins reactive oxygen species spermatozoa thiols thioredoxins

Adult pancreatoblastoma: Current concepts in pathology

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World Journal of Gastroenterology 2021年第26期27卷 4172-4181页

作者： Ayo o omiyale Department of Cellular Pathology Imperial College Healthcare NHS TrustLondon W68RFUnited Kingdom

Adult pancreatoblastoma is an exceptionally rare malignant tumour of the pancreas that mimics other solid cellular neoplasms of the pancreas,which may pose diagnostic *** of its rarity,little is known about its clinical and pathologic *** article reviews the clinical and pathologic features of pancreatoblastoma in adults including differential diagnosis,treatment,and *** pancreatoblastoma commonly occurs in childhood,there have now been more than 70 adult pancreatoblastomas described in the *** is a slight male *** are no symptoms unique to pancreatoblastomas and adult patients are frequently *** most common presenting symptom is abdominal ***,the tumours are often large and ***,pancreatoblastomas are composed of neoplastic cells with predominantly acinar differentiation and characteristic squamoid *** tumours are positive for trypsin,chymotrypsin,lipase,and *** of heterozygosity on chromosome 11p is the most common molecular alteration in *** pancreatoblastomas are aggressive tumours with frequent local invasion,recurrence,and distant *** consists of surgical *** and radiotherapy may have a role in the treatment of recurrent,residual,unresectable,and metastatic *** is important to distinguish pancreatoblastomas from morphological mimics such as acinar cell carcinomas,solid pseudopapillary neoplasms,and pancreatic neuroendocrine neoplasms.

关键词： Pancreas Adult pancreatoblastoma Pancreatic cancer Solid pancreatic mass Non-ductal pancreatic tumours

Burrow morphology of Uca uruguayensis and Uca leptodactylus(Decapoda:ocypodidae)from a subtropical mangrove forest in the western Atlantic

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Integrative Zoology 2013年第3期8卷 307-314页

作者： Glauco B.o.MACHADo João B.L.GUSMÃo-JUNIoR Tânia M.CoSTA Campus Experimental do Litoral Paulista UNESPSão VicenteSão PauloBrazil

The continuous excavation of burrows by fiddler crabs generates bioturbation in the sediment,which can be estimated from burrow *** aim of the present study was to describe the burrow morphology of Uca uruguayensis and *** and its relationship with demography of resident individuals and to estimate the level of bioturbation in the sediment generated by each *** all individuals from each of the 2 species,sex was determined and the carapace width(CW;mm)*** were characterized according to burrow diameter(BD;mm),maximum burrow depth(MBD;mm)and burrow volume(BV;cm^(3)).The density of each species in the study area was also *** both species,the males were larger and occupied burrows with higher BV compared to *** between sexes in relation to the burrow characteristics might reflect sexual dimorphism within the group and are probably related to the fact that males use the burrows for *** and BV showed significant positive relationships with the size of resident *** amount of sediment removed per burrow was estimated from mean BV:10.78 cm^(3)of sediment/burrow for *** and 12.38 cm^(3)of sediment/burrow for *** the density and depth differences between the 2 species,the similarity in burrow volume suggests that *** and *** present the same importance in terms of the bioturbation *** morphology is highly associated with characteristics of the occupant,although extrinsic factors should also be considered,and its description can provide estimates on the bioturbation generated by Uca species in mangrove forests.

关键词： bioturbation burrow structure crab burrowing fiddler crab

A novel confidence estimation method for neural networks in multispectral image classification

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International Journal of Digital Earth 2009年第4期2卷 343-358页

作者： o.Arslan Geodesy and Photogrammetry Engineering Department Engineering FacultyUniversity of Kocaeli41040Turkey

The Digital Earth concept has attracted much attention recently and this approach uses a variety of earth observation data from the global to the local *** techniques have made much progress technically and the methods used for automatic extraction of geo-ralated information are of importance in Digital Earth *** of these methods,artificial neural networks(ANN)techniques,have been effectively used in classification of remotely sensed *** image classification with ANN has been producing higher or equal mapping accuracies than parametric *** studies have,in fact,shown that there is no discernible difference in classification accuracies between neural and conventional statistical *** well designed and trained neural networks can present a better performance than the standard statistical *** are,as yet,no widely recognised standard methods to implement an optimum *** this point of view it might be beneficial to quantify ANN’s reliability in classification *** measure the reliability of the neural network might be a way of developing to determine suitable network *** date,the problem of confidence estimation of ANN has not been studied in remote sensing studies.A statistical method for quantifying the reliability of a neural network that can be used in image classification is investigated in this *** this purpose the method is to be based on a binomial experimentation concept to establish confidence *** novel method can also be used for the selection of an appropriate network structure for the classification of multispectral *** the main focus of the research is to estimate confidence in ANN,the approach might also be applicable and relevant to Digital Earth technologies.

关键词： digital earth neural networks confidence estimation image classification

A comprehensive simulation-based assessment of office building performance adaptability to teleworking scenarios in different Canadian climate zones

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Building Simulation 2022年第6期15卷 995-1014页

作者： Farzam Kharvari Sara Azimi William o’Brien Department of Civil and Environmental Engineering Carleton University1125 Colonel by DriveOttawaOntarioK1S 5B6Canada

Recent studies have shown that office building systems do not adapt well to partial occupancy(e.g.,from teleworking)and thus perform *** a result,this study aims to assess office building performance adaptability by investigating the impact of four different technologies,including occupancy-based lighting,smart plugs(occupancy-based plug load),demand-controlled ventilation(DCV),occupancy-based thermostat,and their cumulative effect in office buildings in six different Canadian climates.A three-story office building is simulated in EnergyPlus version 9.3.0 under five occupancy scenarios,including 0%occupancy,100%occupancy,50%uniformly distributed occupancy across the floor,50%consolidated occupancy scenario where occupants work in core zones,and 50%consolidated occupancy scenario where occupants work in perimeter *** results are compared using energy use intensity(EUI),energy use intensity per occupant(EUP),and the corresponding greenhouse gas(GHG)emissions.A total of 180 simulations demonstrate the occupancy-adaptive technologies are generally most beneficial for low occupancy scenarios and milder *** results also show the cumulative impact of all these technologies on the potential energy savings is significant in the climates under ***,the results show office buildings can improve their performance adaptability during partial occupancy by implementing the studied *** from filling in the current knowledge gap in the literature on partial occupancy,the for the first time results of this study systemically demonstrate how each technology performs under different partial occupancy scenarios and how they perform together at each climate.

关键词： partial occupancy thermostat setpoint smart plug demand-controlled ventilation(DCV) lighting

A Multi-layer Charging of Blast Furnaces with the Help of the Rotary Distributor of Burden

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A Multi-layer Charging of Blast Furnaces with the Help of th...