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Some studies on mathematical models for general elastic multi-structures

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Science China Mathematics 2005年第7期48卷 986-1007页

作者： HUANG Jianguo SHI Zhongci XU Yifeng Department of Mathematics Shanghai Jiaotong University Shanghai 200240 China Division of Computational Science E-Institute of Shanghai Universities Shanghai Normal UniversityChina Institute of Computational Mathematics Academy of Mathematics .and System Sciences Chinese Academy of Sciences Beijing 100080 China Department of Mathematics Shanghai Jiaotong University Shanghai 200240 China

The aim of this paper is to study the static problem about a general elastic multi-structure composed of an arbitrary number of elastic bodies, plates and rods. The mathematical model is derived by the variational principle and the principle of virtual work in a vector way. The unique solvability of the resulting problem is proved by the Lax-Milgram lemma after the presentation of a generalized Korn's inequality on general elastic multi-structures. The equilibrium equations are obtained rigorously by only assuming some reasonable regularity of the solution. An important identity is also given which is essential in the finite element analysis for the problem.

关键词： elastic multi-structures mathematical models unique solvability generalized Korn's inequality equilibrium equations.

The evolution of male mate choice and female ornamentation： a review of mathematical models

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Current Zoology 2018年第3期64卷 323-333页

作者： Courtney L. FITZPATRICK Maria R. SERVEDIO Department of Biology Indiana University Bloomington IN 47405 USA Department of Biology University of North Carolina at Chapel Hill Chapel Hill NC 27516 USA

The evolution of male preferences and of female ornaments in species with traditional sex roles （i.e., polygyny） have been highlighted as areas in need of more active research by an accumulation of recent findings. The theoretical literature on these topics is relatively small and has centered on the evolution of male choice. mathematical models have emphasized that, under polygyny, the evolution of male preferences faces much greater competition costs than does the evolution of female preferences. We discuss ways in which costly male choice can nonetheless evolve, via （1） direct selection that favors preferences, primarily through mating with highly fecund females, （2） mechanisms that rely on indirect selection, which weakly counters competitive costs of male preferences, and （3） genetic constraints, primarily in the form of pleiotropy of male and female preferences and traits. We also review a variety of mathematical models that have elucidated how costs to male preferences can be avoided. Finally, we turn our attention to the relatively scant theoretical literature on the effects of male mate choice on the evolution of female traits. We emphasize the finding that the presence of male preferences cannot be assumed to lead to the evolution of female ornaments during polygyny, and point out situations where models have elucidated ways in which female ornaments can nevertheless evolve.

关键词： female ornaments male mate preferences mathematical models

mathematical models of Hybrid Crypto Code Constructions on Damaged Codes

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Mathematical Models of Hybrid Crypto Code Constructions on D...

作者： Sushchenko Mariia 中国科学技术大学

学位级别：硕士

Cryptosystem is an effective suite of cryptographic algorithms designed to improve security and provide information *** usage allows to protect information from unauthorized access and the impact of random *** this dissertation we are presenting the research of McEliece and Niederreiter *** protect the small and medium businesses we implemented the cryptographic module to ensure the best possible encryption and keeping it *** and its variation known as Niederreiter cryptosystem are underrated but promising solutions for information security threats in business *** cryptosystem is able to face various attacks,even quantum *** is possible to solve two major tasks:to ensure the data transmission through channels with errors（PO= 10-2-10-3）with the necessary certainty level of 0,*** algorithms allow to exchange secret messages between participants by using algebraic-geometric codes over elliptic curves in channels with automatic *** cryptosystem provides complex information *** get the content attacker should decode the random code which is a difficult task with exponential *** the contrary,the authorized user decodes the message using algorithms of polynomial *** promising direction of further research is to verify the obtained results and to test the model in reality-like situation.

关键词： Cryptosystem Hybrid Crypto Code Damaged Codes mathematical models

PHYSICAL AND mathematical models OF POLLUTION DISPERSION IN THE YANGTZE ESTUARY

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China Ocean Engineering 1989年第1期4卷 95-106页

作者： Yi, Jiahao Gu, Peiyu Yan, Lu Nanjing Hydraulic Research Inst China

The method of combining a physical model with a mathematical model is described to study the concentration profile of pollutant dispersion in the Yangtze Estuary. the Experiments are described regarding a jet in a tidal physical model and two-dimensional calculations of diffusion using momentum and mass conservation equations of unsteady flow. The feature of dispersion in the tidal flow, which is different from that in the steady flow such as rivers, is explained. Dilution and dispersion mainly depend on the volume of runoff and tidal range. The results of the measurement and calculation are presented, and it can be seen that they are in good agreement.

关键词： Hydrodynamics Water Pollution mathematical models

Development of database and mathematical models for predicting engine performance parameters using biodiesel

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International Journal of Agricultural and Biological Engineering 2017年第3期10卷 121-129页

作者： P.K.Pranav Thaneswer Patel K.Padmeshore Singh Department of Agricultural Engineering North Eastern Regional Institute of Science and Technology(NERIST)Nirjuli–791109Arunachal PradeshIndia

A database for complete and quick knowledge of biodiesel was developed in Microsoft access linked with interactive interfaced of Visual Basic which contains various information such as biodiesel properties,engine performance parameters and emission *** comparisons of fuel properties among the biodiesel,its blends and engine performance parameters are one of the most attractive features of the developed *** on the data collected from the developed database,the analysis of variance(ANOVA)was carried out to know the effect of fuel properties on engine performance *** fuel properties such as a change in calorific value and viscosity with respect to diesel were found to be significant at 5%level with brake power(BP)and brake specific fuel consumption(BSFC).However,flash point and density were found to be ***,mathematical models were developed for(i)change in BP and(ii)BSFC based on the significant fuel *** model efficiency for BP and BSFC were found to be 92%and 91%*** RMSE values were also calculated from the predicted value and found to be 1.85 and 5.45 for BP and BSFC *** the above statistical facts,it is revealed that the developed mathematical models can be used to predict the change in BP and ***,it is also expected that the developed database shall be expedient for researchers and engineers to locate various information related to biodiesel.

关键词： biodiesel engine performance database mathematical models brake power BSFC

mathematical models for Vacuum Drying Characteristics of Pomegranate Aril

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Journal of Food Science and Engineering 2011年第1期1卷 11-19页

作者： K. Pongtong R. Assawarachan A. Noomhorm School of Environment Resources and Development Asian Institute of Technology Pathumthani Klongluang 12120 Thailand Faculty of Engineering and Agro-lndustry Maejo University Sansai Chiang Mai 50290 Thailand

The aim of this study was to investigate and determine the best mathematical models in describing vacuum drying characteristic of pomegranate arils in the range of 55-75 ℃. The vacuum batch dryer used in the evaluation was successful in drying a thin layer of pomegranate arils from the initial moisture content of 464.02% （d.b.） to 6.18% （d.b.） within 6.5 to 13.5 hr of continuous drying at the above mentioned temperature range. The drying rates increased with an increase in temperature and drying time. Five of the well known semi-theoretical and empirical models were fitted to the vacuum drying of pomegranate arils. The semi-empirical Midilli model has shown an excellent fit to predict drying behavior of the pomegranate arils because this model gave the highest coefficient of determination （RE）, the least chi-square （X2）, and the lowest root mean square error （RMSE）. The total drying occurs during falling period, signifying the influence of moisture diffusion during the drying. The effective diffusivity varied from 1.25× 10^10 to 2.91 × 10^10 m^2/s over the temperature range. Temperature dependence of the diffusivity was well documented by Arrhenius models. The activation energy of moisture diffusion during drying was found to be 40.46 kJ/mol.

关键词： mathematical models vacuum drying pomegranate

Influence of laser power density on damage of comb by photodynamic therapy—simulation and validation of mathematical models

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Chinese Optics Letters 2014年第3期12卷 58-61页

作者：黄乃艳马忠顺王颖曾晶邱海霞唐晓英顾瑛 Department of Laser Medicine Chinese PLA General Hospital School of Life Science and Technology Beijing Institute of Technology

Photodynamic therapy （PDT） has poor therapeutic outcomes for the treatment of port-wine stain （PWS） lesions with long drug-light intervals （DLIs）. This letter investigates the possibility of improving the treatment efficacy through increasing the laser power density using a computer simulation and a cock comb model. The computational model includes a Monte Carlo simulation for the laser distribution and a calculation of the singlet oxygen concentrations （102）. Both simulation and experimental results show that increasing the power density from i00 to 140 mW/cm^2 not only improves the PDT efficacy, but also results in the unwanted skin damage.

关键词： Computer simulation mathematical models Monte Carlo methods

ON THE mathematical models OF THE FARADAIC ADMITTANCE OF IRREVERSIBLE REACTIONS

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Progress in Natural Science:Materials International 1991年第3期 231-239页

作者：张鉴清曹楚南 Academia Sinica Corrosion Science Laboratory Institute of Corrosion and Protection of Metals PRC Shenyang 110015

Based on the basic conditions for admittance,equations(a)and(b)are deduced for irreversible elec-trode reactions whose rates depend upon one or two state variables besides electrode potential under thecondition that the effect of diffusion process can be ***=1/Rt+B/(a+jω).(a)YF=1/Rt+(A+jωB)/(D-ω~2+jωT).(b)It is proved that the parameters in these two equations must fulfill the stability conditions of steady pro-cesses,a>0 for Eq.(a)and T~2≥4D,D>0 for Eq.(b).The results are verified by *** possible applications of the established mathematical models of Faradaic admittance arebriefly discussed.

关键词： electrochemical impedance spectroscopy(EIS) Faradaic admittance mathematical models Kramers-Kronig(K-K)transforms

Application of mathematical models in the Research of Chinese Herbal Compound Prescriptions

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Medicinal Plant 2022年第1期13卷 71-74页

作者： Hongmei TANG Maixun ZHU Shaoqin ZHAI Chongqing Academy of Animal Sciences Rongchang 402460 China

With the interdisciplinary development of multiple disciplines,mathematical models play a role as a bridge in the research process of Chinese herbal compounds,which can make full use of the interrelationships of knowledge,making the research and use of Chinese herbal compounds from complex and cumbersome to *** paper reviewed the research and application of mathematical models in the production and preparation,pharmacodynamics,pharmacokinetics and other aspects of Chinese herbal compound prescriptions,providing a theoretical basis for the development of the modern Chinese medicine industry.

关键词： mathematical models Chinese herbal compound prescription Production and preparation Pharmacodynamics Pharmacokinetics