检索结果-南通市图书馆

Further results on B-tensors with application ;o location of real eigenvalues

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Mathematics in China 2017年第6期12卷 1375-1392页

作者： lu ye Zhongming CHEN College of Economics and Management and Zhejiang Provincial Research Center for Ecological Civilization Zhejiang Sci-Tech University Hangzhou 310018 China Department of Mathematics School of Science Hangzhou Dianzi University Hangzhou 310018 China

We give a further study on B-tensors and introduce doubly B- tensors that contain B-tensors. We show that they have similar properties, including their decompositions and strong relationship with strictly （doubly） diagonally dominated tensors. As an application, the properties of B-tensors are used to localize real eigenvalues of some tensors, which would be very useful in verifying the positive semi-definiteness of a tensor.

关键词： B-tensors doubly B-tensors eigenvalues of tensors decomposition of B-tensors decomposition of doubly B-tensors positive semi-definiteness

COORDINATING PRICING, ORDERING AND ADVERTISING FOR PERISHABLE PRODUCTS OVER AN INFINITE HORIZON

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science and Systems Engineering 2018年第1期27卷 106-129页

作者： ye lu Minghui Xu Yimin Yu School of Economics and Management Wuhan University Wuhan China

Numerous empirical studies show that advertising effort can stimulate demand in both current and future periods, and there is an interaction between pricing, advertising and ordering decisions. How do these decisions interact with each other and what is the effect of advertising on pricing and ordering decisions？ To understand this interaction, we consider a newsvendor-type firm that sells a perishable product in a stable market and dynamically determines the joint ordering, pricing and advertising strategies. The problem is modeled as an infmite horizon newsvendor problem with an advertising carryover effect and price-sensitive demand. We characterize the optimal pricing, advertising and inventory strategies and their comparative statics, and consider how this policy differs from the traditional approach without the advertising effect. We show that the optimal effective advertising level is monotonically increasing with the effective advertising level in the previous period, and hence the optimal strategies （advertising, pricing, inventory level） globally converge to the steady states in the long run. We numerically show that the optimal policy can reap significant profit, which underscores the importance of the advertising-driven ordering and pricing strategies.

关键词： Pricing newsvendor problem advertising carryover effect perishable product

A Cutting Hyperplane Projection Method for Solving Generalized Quasi-Variational Inequalities

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of the Operations Research Society of China 2016年第4期4卷 483-501页

作者： Ming-lu ye College of Mathematics and Information China West Normal UniversityNanchong 637002SichuanChina

The generalized quasi-variational inequality is a generalization of the generalized variational inequality and the quasi-variational *** study for the generalized quasi-variational inequality is mainly concerned with the solution existence *** this paper,we present a cutting hyperplane projection method for solving generalized quasi-variational *** method is neweven if it reduces to solve the generalized variational *** global convergence is proved under certain *** experiments have shown that our method has less total number of iterative steps than the most recent projection-like methods of Zhang et al.(Comput Optim Appl 45:89–109,2010)for solving quasi-variational inequality problems and outperforms the method of Li and He(J Comput Appl Math 228:212–218,2009)for solving generalized variational inequality problems.

关键词： Generalized quasi-variational inequality Cutting hyperplane projection method Point-to-set mapping Pseudomonotone

Floating periodic pontoons for broad bandgaps of water waves

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第11期45卷 1913-1928页

作者： Huaqing JIN Haicheng ZHANG ye lu Daolin XU College of Mechanical and Vehicle Engineering Hunan UniversityChangsha410082China Wuxi lntelligent Control Research Institute Hunan UniversityWuxi214000Jiangsu ProvinceChina China Ship Scientific Research Center Wuxi214082Jiangsu ProvinceChina

The narrow attenuation bands of traditional marine structures have long been a challenge in mitigating water *** this paper,a metastructure(MS)composed of floating periodic pontoons is proposed for broadband water wave *** interaction of surface gravity waves with the MS is investigated using linear wave *** potential solutions of water waves by the MS with a finite array are developed by using the eigenfunction expansion matching method(EEMM),and the band structure of the MS is calculated by the transfer matrix method(TMM),in which the evanescent modes of waves are *** solution is verified against the existing numerical result for a special *** on the present solution,the association between Bragg resonance reflection and Bloch bandgaps is examined,the effects of pontoon geometry are analyzed,and the comparison between floating MS and bottom-mounted periodic structures is conducted.A computational fluid dynamics(CFD)model is further developed to assess the structures in practical fluid environments,and the floating MS presents excellent wave attenuation *** study presented here may provide a promising solution for protecting the coast and offshore structures.

关键词： floating metastructure(MS) wave attenuation bandgap analytical method

Does bicarbonate affect the nitrate utilization and photosynthesis of Orychophragmus violaceus?

在线全文

学校读者我要写书评

暂无评论

Acta Geochimica 2018年第6期37卷 875-885页

作者： ye lu Yanyou Wu Kaiyan Zhang State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang550081China University of Chinese Academy of Sciences Beijing100049China

The effect of bicarbonate(HCO_3^-) on the growth and development of plants varies by species. To better understand inorganic carbon and nitrogen assimilation changes of karst-adaptable plants under different HCO_3^- treatments, we conducted experiments on seedlings and in vitro plantlets of Orychophragmus violaceus(Ov).We found that the vital photosynthesis potential(as measured by net photosynthetic rate, actual photochemical efficiency of photosystem-II, photochemical quenching coefficient, and the instantaneous carbon isotope ratio of3-phosphoglycerate) was consistent under different HCO_3^- treatments of Ov. Bicarbonate's lack of effect on carbon assimilation of Ov may be related to carbonic anhydrase in Ov converting HCO_3^- to H2 O and CO2. In this way, Ov could prevent HCO_3^- ion toxicity and high pH from harming its growth and development under HCO_3^- *** study also found that high HCO_3^- concentrations could promote nitrogen assimilation and utilization of Ov through changes in related indexes(foliar nitrogen isotope fractionation ratio, stable nitrogen isotope assimilation ratio, foliar stable nitrogen isotope fractionation, nitrate nitrogen utilization efficiency, and nitrate utilization share)under different HCO_3^- treatments. Bicarbonate has different effects on photosynthesis and on inorganic nitrogen assimilation of Ov, which may be connected tophotosynthesis providing electrons for nitrate/nitrite reduction through the photosynthetic chain.

关键词： Nitrogen assimilation Photosynthetic capacity HCO3^- Orychophragmus violaceus

OPTIMAL PRICING STRATEGY TO REDUCE FUEL CONSUMPTION IN ELECTRICITY GENERATION WITH SMART METER

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science and Systems Engineering 2015年第1期24卷 81-106页

作者： Xiaoyan Xu Zhuang Ma Liang Xu ye lu School of Management University of Science & Technology of China School of Management Zhejiang University Department of Management Science City University of Hong Kong

It has been widely recognized that the efficiency of a thermal power system can be improved by technological advancement of electricity generation and manipulation of electricity consumption. The smart meter enables two-way communication between the customers and the electricity generation system. The electricity generation system uses price incentive （i.e. a higher price in the peak period and a lower price in the off-peak period） to shift part of demands from peak to off-peak period under the smart grid environment. Given the fact that fuel consumption in each period is a strictly increasing convex function of power output, we propose two-period and multi-period pricing strategies, and study the effect of different pricing strategies on reducing fuel consumption.

关键词： Pricing strategy smart meter energy consumption,convex programming

Accretion by a Neutron Star Moving at a High Kick Velocity in the Supernova Ejecta

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Astronomy and Astrophysics 2007年第1期7卷 91-100页

作者： Xu Zhang ye lu Yong-Heng Zhao National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 Department of Physics Shandong University Jinan 250100 Department of Physics The University of Hong Kong Pokfulam Road Hong Kong

We suggest a two-dimensional time dependent analytic model to describe the accretion of matter onto a neutron star moving at a high speed across the ejecta left in the aftermath of a supernova explosion. The formation of a strange star resulting from the accretion is also addressed. The newborn neutron star is assumed to move outward at a kick velocity of Vns- 10^3 kin s^-1, and the accretion flow is treated as a dust flow. When the neutron star travels across the ejecta with high speed, it sweeps up material, and when the accreted mass has reached a critical value, the neutron star will undergo a phase transition, for instance, to become a strange star. Our results show that the accretion rate decreases in a complicated way in time, not just a power law dependence： it drops much faster than the power law derived by Colpi et al. We also found that the total accreted mass and the phase transition of the neutron star depend sensitively on the velocity of supernova ejecta.

关键词： pulsars general-pulsars-stars neutron-X-rays stars-accretion disk-instability

Injected spectrum for TeV γ-ray emission from the galactic center

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2009年第7期9卷 761-769页

作者： Yan-Ping Wang ye lu Li Chen National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Department of Astronomy Beijing Normal University Beijing 100875 China

The detection of very high energy γ-ray emission from the Galactic center has been reported by four independent groups. One of these γ-ray sources, the 10 TeV -γ-ray radiation reported by HESS, has been suggested as having a hadronic origin when relativistic protons are injected into and interact with the dense ambient gas. Assuming that such relativistic protons required by the hadronic model come from the tidal disruption of a star by the massive black hole of Sgr A＊, we explore the spectrum of the relativis- tic protons. In the calculations, we investigate cases where different types of stars are tidally disrupted by the black hole of Sgr A＊, and we consider that different diffusion mechanisms are used for the propagation of protons. The initial energy distribution of the injected spectrum of protons is assumed to follow a power-law with an exponential cut-off, and we derive the different indices of the injected spectra for the tidal disruption of different types of stars. For the best fit to the spectrum of photons detected by HESS, the spectral index of the injected relativistic protons is about 2.05 when a red giant is tidally disrupted by the black hole of Sgr A＊ and the diffusion mechanism is the Effective Confinement of Protons.

关键词： black hole physics - galaxies jets - Galaxy center

Decontamination Efficacy of Disinfection and Doffing of Medical Protective Clothing:A Combined Mannequin and Personnel Study

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2023年第11期36卷 1105-1109页

作者： XIE Zhong Yi lu Long Xi LI ye FAN Ling Feng YANG Fan Fan lu ye Department of Environmental Health Zhejiang Provincial Center for Disease Control and PreventionHangzhou 310000ZhejiangChina Zhejiang TAILIN Bioengineering Company Limited Hangzhou 310000ZhejiangChina Department of Microorganism Examination Ningbo Center for Disease Control and PreventionNingbo 315000ZhejiangChina

Personal protective equipment(PPE)plays a key role in protecting healthcare workers(HCWs)from highly infectious *** use of PPE based on the level of exposure can prevent severe acute respiratory syndrome coronavirus 2... 详细信息

关键词： protective acute respiratory