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91.
He Renyi 《Southeast Asian Bulletin of Mathematics》2003,26(2):215-221
In this paper, we get some properties in the dual space of Lk-UR and k-SS Banach space.AMS Subject Classification: 46B09 相似文献
92.
El Kebir Boukas Peng Shi Sing Kiong Nguang 《Journal of Mathematical Analysis and Applications》2003,282(1):241-255
This paper studies the problem of stochastic stability and disturbance attenuation for a class of linear continuous-time uncertain systems with Markovian jumping parameters. The uncertainties are assumed to be nonlinear and state, control and external disturbance dependent. A sufficient condition is provided to solve the above problem. An H∞ controller is designed such that the resulting closed-loop system is stochastically stable and has a disturbance attenuation γ for all admissible uncertainties. It is shown that the control law is in terms of the solutions of a set of coupled Riccati inequalities. A numerical example is included to demonstrate the potential of the proposed technique. 相似文献
93.
Franz Merkl 《Probability Theory and Related Fields》2003,126(3):307-338
This article describes the almost sure infinite volume asymptotics of the ground state energy of random Schr?dinger operators
with scaled Gibbsian potentials. The random potential is obtained by distributing soft obstacles according to an infinite
volume grand canonical tempered Gibbs measure with a superstable pair interaction. There is no restriction on the strength
of the pair interaction: it may be taken, e.g., at a critical point. The potential is scaled with the box size in a critical
way, i.e. the scale is determined by the typical size of large deviations in the Gibbsian cloud. The almost sure infinite
volume asymptotics of the ground state energy is described in terms of two equivalent deterministic variational principles
involving only thermodynamic quantities. The qualitative behaviour of the ground state energy asymptotics is analysed: Depending
on the dimension and on the H?lder exponents of the free energy density, it is identified which cases lead to a phase transition
of the asymptotic behaviour of the ground state energy.
Received: 24 June 2002 / Revised version: 17 February 2003
Published online: 12 May 2003
Mathematics Subject Classification (2000): Primary 82B44; Secondary 60K35
Key words or phrases: Gibbs measure – H?lder exponents – Random Schr?dinger operator – Ground state – Large deviations 相似文献
94.
This paper reports the results of a survey intended to discover the extent to which Checkland's Soft Systems Methodology (SSM) is used in practice. Some 300 questionnaires were sent to people who had had some exposure to SSM and, surprisingly, nearly half were returned. The majority described in detail their uses of SSM and most felt that it had been successful. This paper describes the overall quantitative results from the survey as well as presenting a qualitative analysis of the experiences of using SSM. 相似文献
95.
Mike Wright 《The Journal of the Operational Research Society》1994,45(7):758-770
This paper concerns a computer system which has been devised to timetable the county cricket matches in England. The context of the work is discussed and the many constraints and objectives described. Details of the solution method are given; it involves tabu search with a form of diversification dependent on the solution subcosts as well as the overall cost. Experiments are described which suggest that this type of diversification may have wide applicability to large, complex, multi-objective combinatorial problems. 相似文献
96.
This paper outlines the results of a study undertaken to investigate the nature of Community Operational Research (COR). The objective was to contact the people involved in COR through a series of personal interviews and a questionnaire survey, in order to clarify many of the issues that have emerged within the profession relating to the practice of OR within the community and voluntary sector. A total of 20 individuals were successfully contacted, and they have been responsible for at least two-thirds of the projects in the COR area. 相似文献
97.
In 1987 the Canadian Department of National Defence enunciated the Total Force concept. The Total Force is comprised of Regular and Reserve components. The intention is to make maximum use of the Reserve to reduce defence expenditures and at the same time to ensure that military capability remains adequate to support national policy objectives. This paper discusses some of the governing parameters that affect the modelling of the composition of the Total Force and analyses the mix of regular and reserve forces. The interplay between the key factors and their marginal costs will be stressed. The models are employed to study two units in the Canadian Forces, a maintenance support unit and a tactical unit with high operational activity cost. The lessons drawn from these studies are highlighted. 相似文献
98.
The article referenced above was first published online on 7 August 2007 with incorrect pagination; the pagination has now been corrected online and in print. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
99.
Kan‐Yi Pu Yi Chen Xiao‐Ying Qi Chun‐Yang Qin Qing‐Quan Chen Hong‐Yu Wang Yun Deng Qu‐Li Fan Yan‐Qin Huang Shu‐Juan Liu Wei Wei Bo Peng Wei Huang 《Journal of polymer science. Part A, Polymer chemistry》2007,45(16):3776-3787
In this contribution, we demonstrate a new effective methodology for constructing highly efficient and durable poly(p‐phenyleneethynylene) (PPE) containing emissive material with nonaggregating and hole‐facilitating properties through the introduction of hole‐transporting blocks into the PPE system as the grafting coils as well as building the energy donor–acceptor architecture between the grafting coils and the PPE backbone. Poly(2‐(carbazol‐9‐yl)ethyl methacrylate) (PCzEMA), herein, is chosen as the hole‐transporting blocks, and incorporated into the PPE system as the grafting coils via atom transfer radical polymerization. The chemical structure of the resultant copolymer, PPE‐g‐PCzEMA, was characterized by NMR and gel permeation chromatography, showing that the desirable copolymer was obtained with the narrow polydispersity. The increased thermal stability of PPE‐g‐PCzEMA was confirmed by thermogravimetric analysis and differential scanning calorimetry along with its macroinitiator. The optoelectronic properties of this copolymer were studied in detail by ultraviolet‐visible absorption, photoluminescence emission and excitation spectra, and cyclic voltammogram (CV). The results indicate that PPE‐g‐PCzEMA exhibits the solid‐state luminescent property dominated by individual lumophores, and also the energy transfer process from the PCzEMA blocks to the PPE backbone with a relatively higher energy transfer efficiency in the solid‐state compared to that of the solution state. Additionally, the hole‐injection property is greatly facilitated due to the presence of PCzEMA, as confirmed by CV profiles. All these data indicate that PPE‐g‐PCzEMA is a good candidate for use in optoelectronic devices. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3776–3787, 2007 相似文献
100.
Sławomir Rams 《manuscripta mathematica》2003,111(1):29-41
We study the geometry and codes of quartic surfaces with many cusps. We apply Gr?bner bases to find examples of various configurations
of cusps on quartics.
Received: 10 May 2002 / Revised version: 11 November 2002
Published online: 3 March 2003
Permanent address: Institute of Mathematics, Jagiellonian University, ul. Reymonta 4, 30-059 Kraków, Poland. e-mail: rams@mi.uni-erlangen.de,
rams@im.uj.edu.pl
Research partially supported by the Schwerpunktprogramm ``Global methods in complex geometry' of the Deutsche Forschungsgemeinschaft,
and by EAGER.
Mathematics Subject Classification (2000): 14J25, 14J17 相似文献