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A PRICE-SETTING NEWSVENDOR MODEL UNDER CVAR DECISION CRITERION WITH EMERGENCY PROCUREMENT

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Journal of Systems Science and Systems engineering 2010年第1期19卷 85-104页

作者： Minghui XU school of Economics and Management,wuhan university,wuhan 430072,china school of Economics and Management Wuhan University Wuhan China

In this paper, we consider a newsvendor model in which a risk-averse manager faces a stochastic price-dependent demand in either an additive or a multiplicative form. An emergency purchase option is allowed after the realization of demand to satisfy the units that are short. By adopting Conditional value-at-risk （CVaR） as the decision criterion, we aim to investigate the optimal pricing and ordering decisions, and the effects of parameter changes in such a setting. We provide sufficient conditions for the uniqueness of the optimal policy for both demand models. We perforl~, comparative statics analysis to show how the optimal pricing and ordering decision behaves when changing parameters. We also compare our results with those of the newsvendor with a general utility function and with CVaR criterion under lost sales assumption. Our key results include：（i） For both demand models, the optimal selling price is decreasing in risk aversion. Hence, the optimal price of a risk-averse newsvendor is not greater than the optimal price of a risk-neutral newsvendor. （it） In contrary to the lost sales case, for the multiplicative demand model, the optimal order quantity may not be monotonic in risk aversion. Consequently, the optimal risk-averse order quantity may be lower or higher than the optimal risk- neutral counterpart. （iii） For the additive model, the optimal order quantity is strictly increasing in the emergency purchase price, while for the multiplicative model the optimal order quantity has no such a monotonic property. Some numerical examples are conducted to verify our claims and gain more insights about the risk-averse decision-making behaviors.

关键词： Newsvendor model inventory pricing risk aversion conditional value-at-risk

Smooth solutions of non-linear stochastic partial differential equations driven by multiplicative noises

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Science china Mathematics 2010年第11期53卷 2949-2972页

作者： ZHANG XiCheng school of Mathematics and Statistics, wuhan university, wuhan 430072, china school of Mathematics and Statistics Wuhan University Wuhan China

In this paper, we study the regularity of solutions of nonlinear stochastic partial differential equations (SPDEs) with multiplicative noises in the framework of Hilbert scales. Then we apply our abstract result to several typical nonlinear SPDEs such as stochastic Burgers and Ginzburg-Landau equations on the real line, stochastic 2D Navier-Stokes equations (SNSEs) in the whole space and a stochastic tamed 3D Navier-Stokes equation in the whole space, and obtain the existence of their smooth solutions respectively. In particular, we also get the existence of local smooth solutions for 3D SNSEs.

关键词： smooth solutions stochastic partial differential equations stochastic Navier-Stokes equations

Necessary and sufficient conditions for moderate deviations of dependent random variables with heavy tails

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Science china Mathematics 2010年第6期53卷 1421-1434页

作者： LIU Li school of Mathematics and Statistics,wuhan university,wuhan 430072,china school of Mathematics and Statistics Wuhan University Wuhan China

This paper studies the moderate deviations of real-valued extended negatively dependent(END) random variables with consistently varying *** moderate deviations of partial sums are first *** results are then used to establish the necessary and sufficient conditions for the moderate deviations of random sums under certain circumstances.

关键词： moderate deviation extended negative dependence consistently varying tail random sum

Ferroelectric properties of Bi_(3.4)Ho_(0.6)Ti_3O_(12) thin films prepared by sol-gel method

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Science china(Technological Sciences) 2008年第9期51卷 1439-1444页

作者： FU ChengJu1, HUANG ZhiXiong1, LI Jie2 & GUO DongYun3 1 school of Materials Science and Technology, wuhan university of Technology, wuhan 430070, china 2 school of Mechanical engineering, Chongqing university of Science and Technology, Chongqing 400050, china 3 Department of Physics, wuhan university, wuhan 430072, china school of Materials Science and Technology Wuhan University of Technology Wuhan China school of Mechanical engineering Chongqing University of Science and Technology Chongqing China Department of Physics Wuhan University Wuhan China

We have prepared the Ho-substituted bismuth titanate (Bi3.4Ho0.6Ti3O12, BHT) thin films on Pt/Ti/SiO2/Si substrates using sol-gel method. The crystal structure and morphology of the films were characterized using X-ray diffraction and atomic force microscopy. The BHT film shows a single phase of Bi-layered Aurivillius structure and dense microstructure. The 2Pr and 2Ec of the 600-nm-thick BHT film were 38.4 μC/cm2 and 376.1 kV/cm, respectively at applied electric field 500 kV/cm. The dielectric constant and dielectric loss are about 310 and 0.015 at a frequency of 1 MHz, respectively. The Pr value decreased to 93% of its pre-fatigue values after 4.46×109 switching cycles at 1 MHz frenquency, and the BHT film shows good in-sulating behavior according to the test of leakage current.

关键词： Bi3.4Ho0.6Ti3O12 thin film sol-gel method ferroelectric property fatigue dielectric constant

An efficient method for detecting concurrency errors in object-oriented programs

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Science china(Information Sciences) 2012年第12期55卷 2774-2784页

作者： HE YanXiang 1,2,WU Wei 2 & CHEN Yong 2 1 school of Computers,wuhan university,wuhan 430072,china 2 State Key Laboratory of Software engineering,wuhan university,wuhan 430072,china school of Computers Wuhan University Wuhan China State Key Laboratory of Software engineering Wuhan University Wuhan China

Multicore and multi-threaded processors have become the norm for modern ***,concurrent programs have become more and more prevalent despite being difficult to write and *** errors are highly likely to appear in concurrent code,conventional error detection methods such as model checking,theorem proving,and code analysis do not scale smoothly to concurrent *** is an indispensable technique for detecting concurrency errors,but it involves a great deal of manual work and is *** paper presents an automatic method for detecting concurrency errors in classes in object-oriented *** method uses a heuristic algorithm to automatically generate test cases that can effectively trigger ***,each test case is executed automatically and a fast method is adopted to identify the actual concurrency error from anomalous run *** have implemented a prototype of the method and applied it to some typical Java *** shows that our method is more effective and faster than previous work.

关键词： concurrency error dynamic test data race atomicity violations test case generation

Experimental Study on Tensile Properties of Steel Plate Bonded by CFRP

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Journal of wuhan university of Technology(Materials Science) 2008年第5期23卷 727-732页

作者：卢亦焱张号军 school of civil engineering Wuhan University

The tensile properties of five groups of composite specimens, which consist of steel plate bonded by CFRP,were experimentally researched. The failure types, performing characteristics and failure mechanism of the composite specimens were investigated in detail. The influence of different ratio of CFRP on bearing capacity, loading-strain curves, compound modulus, rigidity and ductility of the composite specimens was analyzed. The experimental results indicate that the composite specimen can work harmonically and the steel plate does not break in tension. Comparing with steel plate, the bearing capacity and the rigidity of the composite specimens increase and ductility decreases. The bearing capacity increases sharply with the increase in the number of layers of CFRP. With the increase in CFRP, the yield strength increases slightly and ductility decreases. The experimental researches can provide a theoretical basis for engineering application of combination strengthening.

关键词： steel plate Carbon Fiber Reinforced Polymer (CFRP) combination strengthening tensile properties experimental study

Research of Environment-friendly Low Emissivity Glass

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Journal of wuhan university of Technology(Materials Science) 2007年第2期22卷 385-387页

作者：余峰 school of civil engineering and Architecture Wuhan University of Technology

The environment-friendly glasses which integrate function and structure were introduced, among these glasses can save energy very efficiently due to its low infrared emissivity. The fundamental principle of the low emissivity glass and the research progress of this kind glass were analyzed. Meanwhile, high performance and low applied development trend of emissivity glass were reviewed.

关键词： low emissivity glass(Low-E) environment-friendly research progress development trend

The construction of Markov processes in random environments and the equivalence theorems

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Science china Mathematics 2004年第4期47卷 481-496页

作者： HU Diheschool of Mathematics and Statistics, wuhan university, wuhan 430072, china school of Mathematics and Statistics Wuhan University Wuhan China

In sec.1, we introduce several basic concepts such as random transition function, p-m process and Markov process in random environment and give some examples to construct a random transition function from a non-homogeneous density function. In sec.2, we construct the Markov process in random enviromment and skew product Markov process by p - m process and investigate the properties of Markov process in random environment and the original process and environment process and skew product process. In sec. 3, we give several equivalence theorems on Markov process in random environment.

关键词： radom transition function, p -m process, Markov process in random environment, skew product Markov process, density function.

A novel method of systematic error compensation for a position and orientation system

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Progress in Natural Science:Materials International 2008年第8期18卷 953-963页

作者： Xiuxiao Yuan* school of Remote Sensing and Information engineering, wuhan university, wuhan 430079, china school of Remote Sensing and Information engineering Wuhan University Wuhan 430079 China

A novel method is introduced for self-calibration and elimination of systematic errors for a position and orientation system (POS). The method uses a combined bundle block adjustment with POS data (named the POS-supported bundle block adjustment) without a calibration field. On the basis of delivering strict observation equations for POS data, the specific scheme of compensating the translation and drift systematic errors in a POS is given, and a prototype system WuCAPS is developed. The effects of eliminating POS systematic errors using the POS-supported bundle block adjustment for different ground control conditions are tested using two sets of actual aerial photos. The first set was taken over a flat region in the suburbs of the city of Yingkou in china and tested at a scale of 1:2500. The second set was taken over a high mountainous region in the desert region of Xinjiang in china and tested at a scale of 1:32,000. The empirical results verified that the POS systematic errors can be completely eliminated and the photo elements of exterior orientation obtained by the POS-supported bundle block adjustment can satisfy the requirements of aerial photogrammetric topographic mapping when four full ground control points (GCPs) are emplaced in the corners of the adjustment block for large-scale images of flat regions, but only one full GCP emplaced in the center of the adjustment block is needed for medium-small scale images of mountainous regions. This not only demonstrates the validity of the established mathematical model and the feasibility of the method proposed in this paper, but also avoids the use of a special calibration field. Therefore, it can simplify the existing POS operation rules and dramatically save on practical application costs, laying the theoretical foundation for widespread use of POS.

关键词： Position and orientation system (POS) Systematic error POS-supported bundle block adjustment Self-calibration Accuracy