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A STUDY ON THE MARGINAL ANALYSIS METHOD FOR THE AIRLINE YIELD MANAGEMENT

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Chinese Journal of Aeronautics 1992年第4期 270-276页

作者： Guan Jian-cheng(beijing university of Aeronautics and Astronautics,beijing,100083.{3.)

The current situation and the history of two-fare-class seat inventory control problemfor the airline yield management in the air transportation of the passengers are *** a new marginal analytical method determining the optimal allotment forthe two-class problem is presented with an emphasis on the theoretical aspects of the problemas compared with the traditional *** on the fact that the passengers’ demandnumber is a discrete random variable the formula deduction is demonstrated *** formula obtained in this paper which shows that the optimal seat allotment relatesto the distributions of both high-fare demand and low-fare demand has made someimprovements for the traditional formulae in this *** the formula deductedin this paper to the traditional formulae the results of the computational example of thenew formula show that the method is more accurate and also practical.

关键词： A STUDY ON THE MARGINAL ANALYSIS METHOD FOR THE AIRLINE YIELD MANAGEMENT high

Vaterite or aragonite observed in the prismatic layer of freshwater-cultured pearls from South china

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Progress in Natural Science:Materials International 2009年第7期19卷 817-820页

作者： Hongyan Maa, Anan Sua, Beili Zhangb, Ru-Kang Li a, Longchang Zhou a, Baoli Wang a a College of Chemistry and Chemical Engineering, Guangxi university, Nanning 53.004, china b National Gemstone testing {3., beijing 100013. china [a]College of Chemistry and Chemical Engineering Guangxi University Nanning 530004 China [b]National Gemstone Testing Center Beijing 100013 China

A prismatic layer is present in both freshwater-cultured pearls and seawater-cultured pearls. The phase structure of the prismatic layer of freshwater-cultured pearls is investigated for the first time and novel findings are reported in this paper. X-ray diffraction (XRD), optical microscopy (OM) and micro-infrared (IR) spectroscopy were used to characterize the crystallized layers of high and low-quality freshwater-cultured pearls. Results show that there is no calcite in the prismatic layer of freshwater-cultured pearls, which is different from what was found for seawater-cultured pearls. We found that an aragonite phase was present in the prismatic layer of high-quality freshwater-cultured pearls and that a vaterite or aragonite phase was present in low-quality pearls. Based on this study an internal factor that influences the quality of freshwater-cultured pearls is discussed.

关键词： Vaterite Aragonite Prismatic layer Freshwater-cultured pearls

On some tests-based projection pursuit for elliptical symmetry of a high-dimensional distribution

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Chinese Science Bulletin 1998年第6期43卷 450-458页

作者： JING Ping 1 and ZHU Lixing 2 1. Mathematics Lab, china university of Mining & Technology, beijing 100083. china 2. Probability Lab, Institute of Applied Mathematics, Chinese Academy of Sciences, beijing 100080, china Mathematics Lab China University of Mining & Technology Beijing China Probability Lab Institute of Applied Mathematics Chinese Academy of Sciences Beijing China

Some test statistics of Kolmogorov type and Cramér-von Mises type based on projection pursuit technique are proposed for the testing problem of sphericity of a high-dimensional distribution. The limiting distributions of the test statistics are derived under the null hypothesis and under any fixed alternative. The asymptotic properties of bootstrap approximation are investigated. Furthermore, for computational reasons, an approximation for the statistics, based on the number theoretic method, is suggested.

关键词： bootstrap approximation projection pursuit type statistic elliptical symmetry.

Riemann problem for one-dimensional binary gas enhanced coalbed methane process

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Theoretical & Applied Mechanics Letters 2011年第6期1卷 41-44页

作者： Changfu Tang,) and Xiaodong Wang School of Energy Resources, china university of Geosciences (beijing), beijing 100083. china School of Energy Resources China University of Geosciences (Beijing) Beijing 100083 China

With an extended Langmuir isotherm, a Riemann problem for one-dimensional binary gas enhanced coalbed methane (ECBM) process is investigated. A new analytical solution to the Riemann problem, based on the method of characteristics, is developed by introducing a gas selectivity ratio representing the gas relative sorption affinity. The influence of gas selectivity ratio on the enhanced coalbed methane processes is identified.

关键词： Riemann problem binary gas enhanced coalbed methane method of characteristics gas selectivity ratio

Transmit-reference UWB system based on m-sequence codes

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The Journal of china Universities of Posts and Telecommunications 2010年第1期17卷 25-31页

作者： ZHAO Lin-li,Lü Tie-jun,QIAO Yong-wei School of Information and Communication Engineering,beijing university of Posts and Telecommunications,beijing 100876,{3. [a] School of Information Communication Engineering Beijing University of Posts Telecommunications Beijing 100876 China

In this article, a novel transmit-reference （TR） signaling scheme is proposed for ultra-wideband （UWB） system, where by invoking m-sequence codes the reference and data pulses can be transmitted side by side to increase the data rate. This structure enables demodulation with a simple and practical autocorrelation receiver despite existence of severe inter-pulse interference （IPI） To evaluate detection performance of the new designs, closed-form expression for bit error probability （BRP） is theoretically derived and simulation results confirm the analytical results. In addition, the proposed scheme can be extended to M-ary systems to further improve the data rate and power efficiency.

关键词： UWB TR IPI m-sequence M-ary

analytical Criteria for Local Activity of CNN with Two Ports and Application to Smoothed Chua's Circuit

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Journal of university of Science and Technology beijing 2002年第1期9卷 65-73页

作者： Na Yu, Lequan Min Applied Science School, university of Science and Technology beijing, beijing 100083. {3. E-mail: lqmin@*** Univ Sci & Technol beijing Appl Sci Sch Beijing 100083 Peoples R China

Presents analytic criteria for the local activity theory in two-port cellularneural network (CNN) cells with four local state variables, and gives the application to a smoothedChua's circuit (SCC) CNN with two-port and I 5 S 15 arrays. The bifurcation diagrams of the SCC CNNshow that they are completely the same as those of an SCC CNN with one-port calculated earlier;which do not exist locally passive domain. The evolution of the patterns of the state variables ofthe SCC CNN is stimulated. Oscillatory patterns, chaotic patterns, or divergent patterns may emergeif the selected cell parameters are located in the locally active unstable domains but nearby theedge of chaos domain.

关键词： cellular neural network local activity smoothed Chua's circuit two-port chaos

A Modified Integrated Model of the Internal Structure of Chinese Cultured Pearls

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Journal of Wuhan university of Technology(Materials Science) 2011年第3期26卷 510-513页

作者：马红艳 Key Laboratory of Nonferrous Metals and New Material Processing Technology Ministry of EducationCollege of Materials Science and EngineeringGuangxi University

Optical and micro-infrared microscope were used to observe the internal structure and mineral composition of high and low quality Chinese seawater and freshwater cultured *** clearly reveal that aragonite and calcite are found in seawater cultured pearls,but vaterite is not *** contrast,vaterite and aragonite are found in freshwater cultured pearls,but calcite is not *** on our analysis and observations of the internal structure of high and low quality cultured pearls,a modified integrated model of the internal structure of Chinese cultured pearls was *** revisions to the previous model focus on significant differences within the prismatic layer of Chinese cultured pearls.

关键词： cultured pearls aragonite vaterite calcite integrated model

A New Model for Predicting Ternary Thermodynamic Properties of Solution Phase and Its Application

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Journal of Materials Science & Technology 1993年第3期9卷 199-204页

作者： Zhiyu QIAO Xianran XING Shuzhen DUAN university of Science and Technology beijing,beijing,100083.{3.Chaogui ZHENG beijing university,beijing,100871,{3.

A new geometric asymmetric model for predicting the thermodynamic properties of ternary system from three sub-binaries is presented in this *** analytical expression with good calculating ac- curacy is most simple in all asymmetric *** new model was applied to predict the enthalpies of mixing of the ***-Ag-Sn and NaCl-KCl-CaCl_2 ternary systems which were in good agreements with experimental *** on thermodynamic principles,the importance of the choice of asymmetric component is also *** error analysis indicates that in the case of judging the asymmetric component in ternary system according to the thermodynamic criterion the deviation is *** is of great significance to improve the calculating accuracy for predicting thermodynamic properties of ternary solution phase from the sub-binary ones.

关键词： thermodynamic properties ternary system geometric asymmetric model

Theoretical energy consumption analytical method for metal separation process

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Journal of Thermal Science 2010年第4期19卷 377-382页

作者： Dehong XIA,Yingchun SHANG,Ling REN and Yifan LI Department of Thermal Engineering,university of Science and Technology beijing,beijing 100083 Department of Thermal Engineering University of Science and Technology Beijing Beijing China

The theoretical energy consumption(TEC)analytical methods and the calculated models for the electrolytic and thermal reduction metal separation processes have been put forward based on thermodynamics and physical chemistry principles,providing theoretical foundation for choosing the optimum metal separation *** on the models,the TECs of the Mg separation processes are taken as an example,and have been calculated and analyzed contrastively,including the MgCl_2 electrolytic method,the MgO electrolytic method with inert electrode and with carbon anode,and the silicothermic *** is shown that the thermal method is more reasonable than the electrolytic methods to separate Mg under low efficiency of coal power generation.

关键词： metal separation theoretical energy consumption electrolysis thermal reduction