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251.
Yutaka Baba 《系统科学与系统工程学报(英文版)》2010,19(4):496-503
We study an M/PH/1 queue with phase type working vacation and vacation interruption where the vacation time follows a phase
type distribution. The server serves the customers at a lower rate in a vacation period. The server comes back to the regular
busy period at a service completion without completing the vacation. Such policy is called vacation interruption. In terms
of quasi birth and death process and matrix-geometric solution method, we obtain the stationary queue length distribution.
Moreover we obtain the conditional stochastic decomposition structures of queue length and waiting time when the service time
distribution in the regular busy period is exponential. 相似文献
252.
José Afonso de Oliveira Amarildo Jorge da Silva 《Systemic Practice and Action Research》2011,24(6):565-574
The context of this analysis is the golden years of the decade of the 1960s that served as a backdrop for consolidating capitalism
and the globalized world. The aim is to analyze, understand and establish possible connections between the arts in general
and the world in which modern society operates. This is a theoretical essay anchored in theoretical assumptions of sociology,
arts and the culture of the globalized world and built on the practical experience of these researchers. We use the interpretative
approach and technique of hermeneutic phenomenology to give meaning to historical events and the cultural and artistic implications
of these events in the rise of science and technology. A systemic examination supports the relationship between art, culture,
science and technology. The evidence shows that artistic and cultural issues are essential to make sense of life in society
and in the absence of such basis, the world would be meaningless and humans would lose a sense of direction. It can be concluded
that the arts are becoming increasingly relevant as the virtual world becomes large-scale and truly global, and that the development
of science and technology benefits from the rise of the cultural and artistic world of today. Finally, the correspondence
between the artistic and cultural world and the current scientific and technological development confirms the emergence of
a globalized, digitalised (virtual) knowledge society. 相似文献
253.
Chaohua Jia 《系统科学与复杂性》2011,24(6):1110-1117
The problem of constructing a model reference adaptive control law for an uncertain 1-dimensional parabolic system with one constant coefficient is considered in this paper. Adaptive control law are obtained by Lyapunov redesign method. The energy method for parabolic systems and the Agmon’s inequality are applied in the analysis, which leads to a stronger result than that of Hong and Bentsman (Automatica, 1994). 相似文献
254.
Alexey B. Petrovsky 《系统科学与系统工程学报(英文版)》2007,16(1):22-33
There are many practical decision problems where decision makers' preferences may be inconsistent and contradictory. In this paper, new methods for ordering and classifying multi-attribute objects by discordant collective preferences are suggested. These methods are based on the theory of multiset metric spaces. The proposed techniques are applied to ranking companies and a competitive selection of projects, which are estimated by several experts upon multiple qualitative criteria. 相似文献
255.
Zhaozhi ZHANG Nan JIANG 《系统科学与复杂性》2007,20(4):486-491
Most cipher systems designed thus far are binary-valued or integer-valued cipher systems. Their security relies on the assumption that one-way functions exist. Though the existence of one-way functions has not been proved yet, most cryptographic researchers believe that one-way functions exist. In addition, many candidates for one-way functions have been proposed. Therefore, the key step for developing real-valued cipher systems is to define real one-way functions and to propose candidates for them. In this paper, based on computational complexity theory over the real field, we give two definitions of real one-way functions; one is for digital one-way functions and the other is for general one-way functions. Candidates for these two classes of one-way functions are also proposed. Moreover, we present two examples to demonstrate that the candidates for both digital one-way functions and general one-way functions can be applied to construct secure real-valued cipher systems. 相似文献
256.
Frank Stowell 《Systemic Practice and Action Research》2007,20(5):413-427
Increasingly knowledge has become a determining factor in achieving life’s potential and is the currency of the age. Without
access to Information an individuals’ knowledge base cannot be enriched and without knowledge the individual becomes increasingly
powerless. Advances in technology have provided opportunities for some to add to their stock of knowledge but access to sources
of information is uneven and can lead to social unrest. The availability of information is an important factor in managing
change and empowering citizens. The question about information and power then becomes one of ownership or sovereignty of the
information. If we are to create an open society then we need to ensure that there is open access to knowledge through flexible
and intelligent information systems that are available for all. In this paper we consider if we are truly entering the knowledge
age or the age of ignorance. 相似文献
257.
Alexandra Sauer 《Systemic Practice and Action Research》2008,21(6):497-515
The participation of non-state actors in implementation processes is often understood as a means to increase compliance efficiency. But the implementation of spatial policies frequently focuses on pre-established goals, processes and instruments and thus renders difficult open discourse and shared decision-making. This paper introduces conflict pattern analysis (CPA) as a tool that supports the analysis of the actual actor constellation in order to define efficient approaches that avoid common problems of participatory processes. CPA is a semi-formalised method that helps to identify key-actors, their relations and interaction amongst each other as well as their core beliefs, interests and resources. It aggregates this information to interaction patterns that can be compared, classified and linked to different participatory methods on a theoretically informed basis. Particularly on the local and regional level, this could be the first step for successful (participatory) implementation strategies. 相似文献
258.
This paper considers the Rosenau equation with a moving control?t u + ?_t?_x~4 u + ?_xu + u?x u = a(x + ct)h(x, t), c = 0, x ∈ T = R/(2πZ), t 0.The authors prove that the Rosenau equation with a moving control is locally exact controllable in Hs(T) with s ≥ 0 and globally exponential stable in H~s(T) with s ≥ 2. The two results nontrivially extend the work of(Rosier L and Zhang B Y, 2013) from the BBM equation to the Rosenau equation. 相似文献
259.
Sandrine Turcotte Thérèse Laferrière Christine Hamel Alain Breuleux 《Systemic Practice and Action Research》2010,23(4):285-299
Small remote rural schools in Quebec face an ongoing challenge to provide similar quality educational services than bigger schools. Since 2002, the Remote Network Schools (RNS) initiative afforded schools the opportunity to reinvent their practice by using online tools to experience collaborative learning activities with other remote schools. Teachers and students experienced quality learning and demonstrated agency by implementing the RNS in their context. Measures include: diversity of learning activities, quality of online classroom interactions, changes in teacher beliefs, and shifts in teacher and student roles. Our results show that it is a viable operating method for such schools and that other schools could contemplate implementing such innovative practices. 相似文献
260.
<正> Stock loans are business contracts between borrowers and lenders in which the borroweruses shares of stock as collateral for the loan.Since the value of the collateral is subject to wide andfrequent price swings,valuing such a transaction behaves more like an option pricing problem thana debt valuation problem.This paper will list,prove,and analyze formulas for stock loan valuationwith finite horizon under various stock models,including classical geometric Brownian motion,meanreverting,and two-state regime-switching with both mean-reverting and geometric Brownian motionstates.Numerical examples are reported to illustrate the results. 相似文献