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Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

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Frontiers of Structural and Civil engineering 2024年第2期18卷 309-318页

作者： Ayşe e.ÖZSOYÖZBAY Işıl SANRI KARAPINAR Zehra N.KUTLU İsmail e.KILIÇ Department of Civil engineering Maltepe UniversityIstanbul 34857Turkey School of engineering and Construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vulnerability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inİstanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vulnerability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vulnerability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vulnerability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is believed to advance the current applications for vulnerability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vulnerability assessment cultural heritage local site effect

A CONJUGATe GRADIeNT MeTHOD FOR DISCReTe-TIMe OUTPUT FeeDBACK CONTROL DeSIGN

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Journal of Computational Mathematics 2012年第3期30卷 279-297页

作者： e1-Sayed M.e. Mostafa Department of Mathematics Faculty of Science Alexandria University Alexandria Egypt

In this paper, the discrete-time static output feedback control design problem is con- sidered. A nonlinear conjugate gradient method is analyzed and studied for solving an unconstrained matrix optimization problem that results from this optimal control prob- lem. In addition, through certain parametrization to the optimization problem an initial stabilizing static output feedback gain matrix is not required to start the conjugate gradi- ent method. Finally, the proposed algorithms are tested numerically through several test problems from the benchmark collection.

关键词： Output feedback control Nonlinear conjugate gradient methods Nonlinearprogramming.

Decision and Coordination of an e-commerce Supply Chain Considering Returns and Network externalities

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Journal of Systems Science and Systems engineering 2024年第5期33卷 552-575页

作者： Liang Shen Fei Lin Yuyan Wang Luping Ding T.C.e.Cheng Dexia Wang School of Public Finance and Taxation Shandong University of Finance and Economicsjinan 250014China bschool of Management Science and engineering Shandong University of Finance and EconomicsJinan 250014China PolyU Business School The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077China

Considering the large number of returns in online sales and the network externalities of e-platforms,we develop a decentralized model and a centralized model to explore the impacts of returns and network externalities on e-commerce supply chain(eCSC)*** show that in the decentralized model,the service level,price,market demand,and eCSC members’profits increase with the network externality ***,the service level and price increase,while the market demand and eCSC members’profits decrease with the product return *** centralized model is the optimal operating mode when it is properly *** design the“commission and return cost-sharing”contract to optimize eCSC,in which the proportion of the e-platform’s sharing of the return handling cost is exactly equal to the proportion of the system profit after *** on the decentralized model,we develop two extended models in which we endogenize the impacts of the service level and return rate on the network externality *** comparisons between the extended and decentralized models,we show that high-quality service can improve eCSC’s profitability,while a high return rate hurts its economic performance.

关键词： e-commerce supply chain coordination mechanism network externalities return products

Dependence of Mean and Peak Streamflow on Basin Area in the Conterminous United States

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Journal of earth Science 2016年第1期27卷 83-88页

作者： William e.Winston Robert e.Criss Department of earth and Planetary Sciences Washington University in St.Louis

Basin area is the primary control on both mean and peak streamflows, but relationships vary with regional meteorological conditions. Rich historical data sets permit deduction of these relationships for most areas of the United States, revealing both expected and unexpected correlations. On log-log plots, mean flows for most basins with 〉75 cm/y rainfall have unit slopes, with the y-intercept approximating the mean annual runoff. Lower slopes characterize regions where runoff is greatest at high topographic elevations, or where significant withdrawals for irrigation occur at lower elevations. Peak flows also correlate strongly with basin area, but the regressions for most regions have slopes ranging from 0.4 to 0.9, and y-intercepts that increase with increasing flood recurrence interval. The slopes on these log-log plots for peak flows are highest in cool regions with low sunshine and low evapotranspiration, and lowest where sunshine is abundant, evapotranspiration is high, and small convective storm cells are common. effects of relief are small and inconsistent. Peak flows of small watersheds are huge compared to their mean flows, commonly being several thousand times greater, particularly in the USA midcontinent where the slopes for peak flows are low.

关键词： floods GIS runoff rivers.

Fish embryo and juvenile size under hypoxia in the mouth- brooding African cichlid Pseudocrenilabrus multicolor

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Current Zoology 2012年第3期58卷 401-412页

作者： e.e. ReARDON L.J. CHAPMAN Department of Biology McGill University 1205 Dr. Penfield Ave Montreal Quebec H3A 1B 1 Canada Wildlife Conservation Society 2300 Southern Boulevard Bronx NY 10460 USA

We used a field survey and a laboratory rearing experiment to （a） examine response （size and survival） to life-long hypoxia in offspring of the African maternal mouth-brooding cichlid Pseudocrenilabrus multicolor victoriae （Seegers） and （b） explore the degree to which developmental response can be environmentaUy-induced. embryo size metrics were quantified in 9 field populations across a range of dissolved oxygen （DO） concentrations. In the laboratory, first generation （F1） broods of low-DO origin were reared under high or low DO. Brooding period was quantified for the mothers; and egg size, egg metabolic rate and juvenile size-at-release were quantified in their （F2） offspring. The F2 offspring were split and grown for 3 months post-release under high or low DO, and juvenile size and survival were quantified. In the field survey, across stages, embryos from low-DO field populations were shorter and weighed less than embryos from high-DO populations. In the laboratory experi- ment, F2 eggs and juveniles-at-release from mother＇s mouth did not differ in mass, length, survival regardless of development DO environment. However, juveniles diverged in size after leaving mother＇s mouth, exhibiting smaller size when grown under low DO. Size differences in embryo size across field populations and divergence in embryo size after release from the mother＇s mouth support predictions for smaller body size under hypoxia. There was no evidence for negative effects on survival of juveniles after 3 months. Brooding period was 16% shorter in females reared under low DO suggesting that hypoxia may accelerate embryo de- velopment. This work provides insights into how bearer fishes respond to hypoxic stress relative to fishes with no post-spawning parental care; a shorter brooding interval and smaller body size may provide an optimal solution to parent and embryo survival under hypoxia in brooding fishes [Current Zoology 58 （3）： 401-412, 2012].

关键词： African cichlid Lake Victoria Life-history Parental care Dissolved oxygen

Coating of finely dispersed particles by two-fluid nozzle

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Particuology 2018年第3期16卷 80-93页

作者： N. Hampel e. Roydeva A. Buck e. Tsotsas Thermal Process engineering Otto yon Guericke University Universitatsplatz 2 39106 Magdeburg Germany

Particle coatings are used extensively to generate dispersed solids with well-defined properties, e.g., to protect active ingredients, with most coating processes using core particles of a diameter larger than 200 μm. This work contributes to the development of a coating process for fine dispersed particles （diam- eter less than 50 μm） by combining two particle-formulation processes, namely, coating and spray drying. The feasibility of the operation is based on and demonstrated by the innovative application of a two-fluid nozzle. experiments were conducted by using glass particles as core particles and sodium benzoate as the coating agent. The coating of finely dispersed particles is achieved by the spraying of particles and coating solution as a homogeneous suspension. The aim is to create droplets with only one contained particle at the nozzle outlet. After evaporation of the water in the droplet, a thin solid film is built on the particle surface. The suspension viscosity was measured and compared with empirical equations from the literature. The liquid-film thickness on the particle surface was calculated to predict the building of a uniform coating layer or agglomerates. In this study, the feasibility of pneumatic transport through the nozzle and an investigation of the process were illustrated. The agglomeration fraction and degree of coating of the particle surface were analyzed optically by scanning electron microscopy. In this way, the influence of different processes and suspension parameters on the product quality were determined.

关键词： Coating Spray drying Fine dispersed particle Two-fluid nozzle

Metal-containing nanomaterials as lubricant additives: State-of-the-art and future development

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Friction 2019年第2期7卷 93-116页

作者： Igor e.UFLYAND Vladimir A.ZHINZHILO Victoria e.BURLAKOVA Department of Chemistry Southern Federal University Department of Chemistry Don State Technical University

This review focuses on the effect of metal-containing nanomaterials on tribological performance in oil lubrication. The basic data on nanolubricants based on nanoparticles of metals, metal oxides, metal sulfides, nanocomposities, and rare-earth compounds are generalized. The influence of nanoparticle size, morphology, surface functionalization, and concentration on friction and wear is analyzed. The lubrication mechanisms of nanolubricants are discussed. The problems and prospects for the development of metal-containing nanomaterials as lubricant additives are considered. The bibliography includes articles published during the last five years.

关键词： coefficient of friction metal-containing nanomaterials nanolubricants nanoparticles wear

CHIRAL RING OF Sp(N) AND SO(N) SUPeRSYMMeTRIC GAUGe THeORY IN FOUR DIMeNSIONS

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Chinese Annals of Mathematics,Series B 2003年第4期24卷 403-414页

作者： e.WITTeN Institute for Advanced Study PrincetonNJ 08540USA

The chiral ring of classical supersymmetric Yang-Mills theory with gauge group Sp(N) or SO(N) is computed, extending previous work (of Cachazo, Douglas, Seiberg, and the author)for SU(N). The result is that, as has been conjectured, the ring is generated by the usualglueball superfield S ～ Tr WαWα, with the relation Sh = 0, h being the dual Coxeter *** this proposition has important implications for the behavior of the quantum theory,the statement and (for the most part) the proofs amount to assertions about Lie groups withno direct reference to gauge theory.

关键词： Chiral ring Gauge group Lie group Supersymmetric gauge theory

Formation of efficient dye-sensitized solar cells by introducing an interfacial layer of hierarchically ordered macro-mesoporous TiO_2 film

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Science China Chemistry 2011年第6期54卷 930-935页

作者： HALPeRT Jonathan e State Key Laboratory of Multi-phase Complex Systems Institute of Process engineering Chinese Academy of Sciences

Hierarchically ordered macro-mesoporous TiO2 films (Ti-Ma-Me) were fabricated on fluorine-doped tin oxide (FTO) substrates through the confinement self-assembly method. The prepared Ti-Ma-Me possesses periodically ordered structure and a large specific surface area, which was applied as an interfacial layer between the nanocrystalline TiO2 film (P25-TiO2) and FTO electrode in the dye-sensitized solar cell (DSSC). The introduction of a Ti-Ma-Me interfacial layer increased the shortcircuit current density (Jsc) from 7.49 to 10.65 mA/cm2 and the open-circuit voltage (Voc) from 0.65 to 0.70 V as the result of its improved light harvesting efficiency by allowing for the high roughness factor and enhanced multiple internal reflection or scattering as well as reducing the back-transport reaction by blocking direct contact between the electrolyte and FTO electrode. Therefore, the photovoltaic conversion efficiency (η) was improved by 83% from 3.04% to 5.55%, as compared to a device using a bare P25 TiO2 photoanode.

关键词： dye-sensitized solar cells hierarchical ordered macro-mesoporous photoanode