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Stochastic Earned Duration Analysis f.r Project Schedule Management

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Engineering 2022年第2期8卷 148-161页

作者： f.rnando Acebes David Poza JoséManuel González-Varona Adolf. l.pez-Paredes GIR INSISOC-Department of.Business Organization and CIM School of Industrial EngineeringUniversity of ValladolidValladolid 47011Spain

Earned duration management(EDM)is a methodology f.r project schedule management(PSM)that can be considered an alternative to earned value management(EVM).EDM provides an estimation of.devia-tions in schedule and a f.nal project duration *** is a key dif.erence between EDM and EVM:In EDM,the value of.activities is expressed as work periods;whereas in EVM,value is expressed in terms of.*** this paper,we present how EDM can be applied to monitor and control stochastic *** explain the methodology,we use a real case study with a project that presents a high level of.uncertainty and activities with random *** analyze the usability of.this approach according to the activities network topology and compare the EVM and earned schedule methodology(ESM)f.r PSM.

关键词： Earned duration management Earned value management Stochastic project control Duration f.recasting Uncertainty

Interplay among cellular polarization,lipoprotein metabolism and hepatitis C virus entry

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World Journal of.Gastroenterology 2011年第22期17卷 2683-2690页

作者： Ignacio Benedicto f.ancisca Molina-Jiménez Ricardo Moreno-Otero Manuel l.pez-Cabrera Pedro l Majano Molecular Biology Unit Hospital Universitario de la Princesa Instituto de Investigación Sanitaria Princesa (IP) Madrid 28006 Spain CIBERehd Instituto de Salud Car- los Ⅲ Madrid 28029 Spain liver Unit Hospital Universitario de la Princesa Instituto de Investigación Sanitaria Princesa (IP) Madrid 28006 Spain Centro de Biología Molecular Severo Ochoa CSIC-UAM Madrid 28049 Spain

Hepatitis C virus (HCV) inf.cts more than three million new individuals worldwide each year. In a high percent age of.patients, acute inf.ctions become chronic, eventually progressing to f.brosis, cirrhosis, and hepatocellular carcinoma. Given the lack of.ef.ective prophylactic or therapeutic vaccines, and the limited sustained virological response rates to current therapies, new approaches are needed to prevent, control, and clear HCV *** into the host cell, being the f.rst step of.the viral cycle, is a potential target f.r the design of.new antiviral compounds. Despite the recent discovery of.the tight junction-associated proteins claudin-1 and occludin as HCV co-receptors, which is an important step towards the understanding of.HCV entry, the precise mechanisms are still largely unknown. In addition, increasing evidence indicates that tools that are broadly employed to study HCV inf.ction do not accurately ref.ect the real process in terms of.viral particle composition and host cell phenotype. Thus, systems that more closely mimic natural inf.ction are urgently required to elucidate the mechanisms of.HCV entry, which will in turn help to design antiviral strategies against this part of.the inf.ction process.

关键词： Cellular polarization Tight junctions lipoprotein metabolism Hepatitis C virus

Two-Stream Approximation to the Radiative Transf.r Equation:A New Improvement and Comparative Accuracy with Existing Methods

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Advances in Atmospheric Sciences 2024年第2期41卷 278-292页

作者： f.Momo TEMGOUA l.Akana NGUIMDO DNJOMO Environmental Energy Technologies laboratory(EETl) Faculty of SciencesUniversity of YaoundéPO Box 812 YaoundéCameroon Department of.Electrical and Electronic Engineering Faculty of Engineering and TechnologyUniversity of BueaPO Box 63 BueaCameroon

Mathematical modeling of.the interaction between solar radiation and the Earth's atmosphere is f.rmalized by the radiative transf.r equation(RTE), whose resolution calls f.r two-stream approximations among other methods. This paper proposes a new two-stream approximation of.the RTE with the development of.the phase f.nction and the intensity into a third-order series of.legendre polynomials. This new approach, which adds one more term in the expression of.the intensity and the phase f.nction, allows in the conditions of.a plane parallel atmosphere a new mathematical f.rmulation of.γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Delta f.nction and Modif.ed Eddington, and second-order approximation methods with ref.rence to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work also determines the conversion f.nction of.the proposed New Method using the f.ndamental def.nition of.two-stream approximation(f.TSA) developed in a previous work. Notably,New Method has generally better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision f.r wide domains of.the zenith angle μ 0, but tends to deviate f.om the Disort method with the zenith angle, especially f.r high values of.optical thickness. In spite of.this divergence in ref.ectance f.r high values of.optical thickness, very strong correlation with the Disort method(R ≈ 1) was obtained f.r most cases of.optical thickness in this study. An analysis of.the legendre polynomial series f.r simple f.nctions shows that the high precision is due to the f.ct that the approximated f.nctions ameliorate the accuracy when the order of.approximation increases, although it has been proven that there is a limit order depending on the f.nction f.om which the precision is lost. This observation indicates that increasing the order of.app

关键词： Radiative Transf.r Equation two-stream method legendre polynomial optical thickness moments of.specif.c intensity conversion f.nction transmittance ref.ectance

Seed Morphology of.Some Species of.<i>Indigof.ra</i>(f.baceae) f.om Saudi Arabia (Identif.cation of.Species and Systematic Signif.cance)

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American Journal of.Plant Sciences 2011年第3期2卷 484-495页

作者： f. A. al-Ghamdi 不详

Seeds of.18 species of.Indigof.ra l. were examined with the scanning electron microscope and the light microscope. Macro- and micromorphological characters, including seed shape, colour, size, surf.ce, epidermal cell shape, anticlinal boundaries, outer periclinal cell wall and relief.of.outer cell walls, are presented. Two types of.basic anticlinal cell wall boundaries and two types of.relief.outer cell walls are recognized and two dif.erent shapes of.the outer periclinal cell wall are described. A key f.r the identif.cation of.the investigated taxa based on seed characters is provided.

关键词： Seeds Morphology Indigof.ra f.baceae Saudi Arabia

Water, land, and energy use ef.iciencies and f.nancial evaluation of.air conditioner cooled greenhouses based on f.eld experiments

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Journal of.Arid land 2021年第4期13卷 375-387页

作者： Ibtihal al-MANTHRIA Abdulrahim M al-ISMAIlIA Hemesiri KOTAGAMAB Mumtaz KHANC l H Janitha JEEWANTHAD Department of.Soils Water and Agricultural EngineeringSultan Qaboos UniversityMuscat PC123Oman Department of.Natural Resource Economics Sultan Qaboos UniversityMuscat PC123Oman Department of.Plant Science College of Agricultural and Marine SciencesSultan Qaboos UniversityMuscat PC123Oman Centre f.r f.ture Materials University of Southern QueenslandToowoomba QLD 4350Australia School of.Mechanical and Electrical Engineering University of Southern QueenslandToowoomba QLD 4350Australia

High temperature and humidity can be controlled in greenhouses by using mechanical ref.igeration cooling system such as air conditioner(AC)in warm and humid *** study aims to evaluate the techno-f.nancial aspects of.the AC-cooled greenhouse as compared to the evaporative cooled(EV-cooled)greenhouse in winter and summer *** quonset single-span prototype greenhouses were built in the Agriculture Experiment Station of.Sultan Qaboos University,Oman,with dimensions of.6.0 m long and 3.0 m *** AC-cooled greenhouse was covered by a rockwool insulated polyethylene plastic sheet and light emitting diodes(lED)lights were used as a source of.light,while the EV-cooled greenhouse was covered by a transparent polyethylene sheet and sunlight was used as light *** cultivars of.high-value lettuce were grown f.r *** evaluate the technical ef.iciency of.greenhouse perf.rmance,we conducted measures on land use ef.iciency(lUE),water use ef.iciency(WUE),gross water use ef.iciency(GWUE)and energy use ef.iciency(EUE).f.nancial analysis was conducted to compare the prof.tability of.both *** results showed that the lUE in winter were 10.10 and 14.50 kg/m^(2) f.r the AC-and EV-cooled greenhouses,***,the values reduced near to 6.80 kg/m^(2) in both greenhouses in *** WUE of.the AC-cooled greenhouse was higher than that of.the EV-cooled greenhouse by 3.8%in winter and 26.8%in *** GWUE was used to measure the total yield to the total greenhouse water consumption including irrigation and cooling water;it was higher in the AC-cooled greenhouse than in the EV-cooled greenhouse in both summer and winter seasons by almost 98.0%–99.4%.The EUE in the EV-cooled greenhouse was higher in both *** analysis showed that in winter,gross return,net return and benef.t-to-cost ratio were better in the EVcooled greenhouse,while in summer,those were higher in the AC-cooled *** values of.internal rate o

关键词： land use ef.iciency energy use ef.iciency water use ef.iciency gross water use ef.iciency f.nancial evaluation air conditioner cooled greenhouse evaporative cooled greenhouse

Nonlinear mechanics of.a ring structure subjected to multi-pairs of.evenly distributed equal radial f.rces

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Acta Mechanica Sinica 2017年第5期33卷 942-953页

作者： Q. Chen f. Sun Z. Y. li l. Taxis N. Pugno Biomechanics laboratory School of Biological Science and Medical Engineering Southeast University State Key laboratory of.Mechanics and Control of.Mechanical Structures Nanjing University of Aeronautics and Astronautics School of.Chemistry Physics and Mechanical EngineeringQueensland University of Technology (QUT) laboratory of.Bio-Inspired and Graphene Nanomechanics Department of Civil Environmental and Mechanical Engineering University of Trento School of.Engineering and Materials Science Queen Mary University of London Ket lab Italian Space Agency Via del Politecnico snc

Combining the elastica theory, f.nite element (f.) analysis, and a geometrical topological experiment, we studied the mechanical behavior of.a ring subjected to multi-pairs of.evenly distributed equal radial f.rces by looking at its seven distinct states. The results showed that the theoretical predictions of.the ring def.rmation and strain energy matched the f. results very well, and that the ring def.rmations were comparable to the topological experiment. Moreover, no matter whether the ring was compressed or tensioned by N-pairs of.f.rces, the ring always tended to be regular polygons with 2N sides as the f.rce increased, and a proper compressive f.rce def.rmed the ring into exquisite f.ower-like patterns. The present study solves a basic mechanical problem of.a ring subjected to lateral f.rces, which can be usef.l f.r studying the relevant mechanical behavior of.ring structures f.om the nano- to the macro-scale.

关键词： Ring structures Mechanical properties Shape Strain energy

l^p Estimates of.Rough Maximal f.nctions along Surf.ces with Applications

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Acta Mathematica Sinica,English Series 2016年第8期32卷 925-942页

作者： Ahmad al-SalMAN Abdulla M.JARRAH Department of.Mathematics Yarmouk University

Abstract In this paper, we study the lp mapping properties of.certain class of.maximal oscillatory singular integral operators. We prove a general theorem f.r a class of.maximal f.nctions along surf.ces. As a consequence of.such theorem, we establish the lp boundedness of.various maximal oscillatory singular integrals provided that their kernels belong to the natural space l log l（Sn-1）. Moreover, we highlight some additional results concerning operators with kernels in certain block spaces. The results in this paper substantially improve previously known results.

关键词： Oscillatory singular integrals rough kernels maximal f.nctions highly monotone curves

Delayed Ionization and Delayed Detachment in Molecules and Clusters

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Chinese Journal of.Chemical Physics 2009年第2期22卷 162-170页

作者： f. lépine B. Baguenard B. Concina M. A. lebeault C. Bordas Université de lyon F-69522 Lyon France Université lyon 1 Villeurbanne CNRS UMR 5579 LASIM

The evolution of.a molecular system excited above its ionization threshold depends on a number of.parameters that include the nature of.the excited states and their couplings to the various continua. The general nature of.the processes governing this evolution depends also essentially on the complexity of.the molecule, more precisely on its size, density of.states, and strength of.the couplings among the various internal degrees of.f.eedom. In this paper we address the question of.the transition between autoionization that prevails in small molecules, and delayed ionization occurring in larger molecules or clusters. This transition is illustrated by autoionization of.Na2 Rydberg states on one hand, delayed ionization in f.llerene C60, and delayed detachment in small cluster anions on the other hand. all processes are studied in the case of.nanosecond laser excitation, corresponding to a rather slow deposition of.the internal energy.

关键词： Autoionization Autodetachment Thermionic emission

Stripping Voltammetric Determination of.Timolol Drug in Pharmaceuticals and Biological f.uids

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American Journal of.Analytical Chemistry 2011年第2期2卷 174-181页

作者： ali f. al-Ghamdi 不详

A sensitive and reliable stripping voltammetric method was developed to determine timolol drug. This method is based on the adsorptive accumulation of.the drug at a hanging mercury drop electrode (HMDE) and then a negative sweep was initiated, which yield a well def.ned cathodic peak at –850 mV versus (Ag/AgCl) silver ref.rence electrode. To achieve high sensitivity, various experimental and instrumental variables were investigated such as supporting electrolyte, pH, accumulation time and potential, scan rate, f.equency, pulse amplitude, convection rate and working electrode area. The monitored adsorptive current was directly proportional to the concentration of.timolol and it shows a linear response in the range f.om 1 × 10–7 to 1.5 × 10–6 mol●l–1 of.this drug (correlation coef.icient = 0.998) and the detection limit (S/N = 3) is 1.26 × 10–9 mol●l–1 at an accumulation time of.30 sec. The developed adsorptive stripping voltammetry (AdSV) procedure shows a good reproducibility, the relative standard deviation RSD% (n = 8) at a concentration level of.1 × 10–6 mol●l–1 of.timolol was 0.13%, whereas the method accuracy was indicated via the mean recovery of.110% ± 1.414%. Possible interf.rences by several substances usually present in the pharmaceutical f.rmulations have been also evaluated. The applicability of.this approach was illustrated by the determination of.the drug in pharmaceutical preparation and biological f.uids such as serum and urine.

关键词： Stripping Voltammetry HMDE Timolol Urine Serum