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31.
Efficient Decomposition Techniques for Symbolic Analysis of Large-Scale Analog Circuits by State Variable Method 总被引:1,自引:0,他引:1
New tearing techniques for the systematic formulation of the state equations in symbolic normal-form for linear and nonlinear time-invariant large-scale analog circuits are developed. Some examples are given to illustrate the decomposition procedure and the assignment of the connection sources. The partial symbolic state equations of the opamp A 741 are obtained using the tearing approach, while these equations cannot be written working on the whole circuit. 相似文献
32.
Gheorghe?I.?RusuEmail author George?G.?Rusu Mihai?E.?Popa 《Materials Research Innovations》2003,7(6):372-380
The investigated compounds are some derivatives of orthotolidin-N,N-bis (4-aminobenzene-2-sulphonic) acid. The temperature dependences of the electrical conductivity and Seebeck coefficient are studied on the thin films deposited from dimethylformamide solution onto glass substrates. It is known that the investigated compounds have typical semiconducting properties. The values of some important parameters of the films (thermal activation energy of electrical conduction, concentrations and mobilities of charge carriers) have been determined. The correlations between some of these parameters and molecular structure of the respective compounds are discussed. 相似文献
33.
Franco Cataldo Mihai V. Putz Ornella Ursini Giancarlo Angelini D. Anibal Garcia-Hernandez Arturo Manchado 《Fullerenes, Nanotubes and Carbon Nanostructures》2016,24(3):195-201
It is shown that graphite oxide (GO) and both heavily ozonized C60 and C70 fullerenes, known as “fullerene ozopolymers,” are paramagnetic materials with a very strong electron spin resonance (ESR) signal at room temperature. When thermally annealed, the paramagnetic centers are gradually lost in large part. This occurs at 350°C in the case of GO, while for fullerene ozopolymers, a higher temperature is required, reaching the same results in the end. The half-width of ESR signal is linked to the distribution of paramagnetic centers. Once again, striking analogies were found in the half-width of the ESR signal measured on GO and fullerene ozopolymers, at least in the temperature range of 25–450°C. Similarly, the same g-factor values, which are diagnostic for understanding the chemical nature of paramagnetic centers, were found on both GO and fullerene ozopolymers in all ranges of temperature considered. 相似文献
34.
Mihai Nadin 《国际通用系统杂志》2013,42(8):860-867
Weights are used to measure relative importance of multiple attributes or objectives, which influence evaluation or decision results to a great degree. Thus, analyzing weight sensitivity is an important work for a multi-attribute evaluation or decision. A measuring method based on the inclined angle of two vectors is proposed in this paper in order to solve the weight sensitivity of a multi-attribute evaluation with isotonicity characteristic. This method uses the cosine of the inclined angle to measure the weight sensitivity based on preferences or preference combinations. Concepts of sensitivity space, degree, and angle are given, and the relevant measurement method is discussed and proved. Also, this method is used for the choice of the water environment protection projects in Heyuan City. 相似文献
35.
Charalambides M. Flegkas P. Pavlou G. Rubio-Loyola J. Bandara A.K. Lupu E.C. Russo A. Dulay N. Sloman M. 《Network and Service Management, IEEE Transactions on》2009,6(1):15-30
Policy-based management provides the ability to (re-)configure differentiated services networks so that desired Quality of Service (QoS) goals are achieved. This requires implementing network provisioning decisions, performing admission control, and adapting bandwidth allocation to emerging traffic demands. A policy-based approach facilitates flexibility and adaptability as policies can be dynamically changed without modifying the underlying implementation. However, inconsistencies may arise in the policy specification. In this paper we provide a comprehensive set of QoS policies for managing Differentiated Services (DiffServ) networks, and classify the possible conflicts that can arise between them. We demonstrate the use of Event Calculus and formal reasoning for the analysis of both static and dynamic conflicts in a semi-automated fashion. In addition, we present a conflict analysis tool that provides network administrators with a user-friendly environment for determining and resolving potential inconsistencies. The tool has been extensively tested with large numbers of policies over a range of conflict types. 相似文献
36.
Iulian Riposan Mihai Chisamera Stelian Stan Pavel Toboc Geir Grasmo Douglas White Chris Ecob Cathrine Hartung 《Journal of Materials Engineering and Performance》2011,20(1):57-64
Two main chemistry systems of micro-inclusions can be identified in ductile iron: Ca-S-X and Mg-Si-O-X with the majority of
the inclusions regardless of treatment type and location being of the second type, silicates. Laboratory investigations have
shown that simple silicates were present in the matrix, while more complex silicates were present in conjunction with graphite,
probably acting as graphite nucleation sites. In these more complex silicates, elevated levels of Al, Ca, Ce and La were typical.
Comparing micro-particles embedded in iron matrix and graphite nodules of iron treated with pure Mg-metal and iron treated
with MgFeSi alloy showed a higher amount of complex silicates with elevated Al-levels in the iron treated with MgFeSi. Further
laboratory investigation was undertaken to explore which source of Al and which range of residual Al would have a favorable
impact on the graphite nucleation in ductile iron. The work showed that a residual aluminum of 0.005 to 0.020 wt.% appears
to be beneficial for improving ductile iron solidification characteristics without the incidence of pinholes. Greatest benefits
were achieved when introducing the Al into the iron via an inoculant late during processing or via a pre-conditioner to the
base iron. Al added via the MgFeSi provided less benefit. Some case studies illustrating the effect of Al in ductile iron
are also presented, as Al-containing pre-conditioner or/and Al-bearing, FeSi inoculant application. 相似文献
37.
Marius Eugen Ciurea Ada Maria Georgescu Stefana Oana Purcaru Stefan-Alexandru Artene Ghazaleh Hooshyar Emami Mihai Virgil Boldeanu Daniela Elise Tache Anica Dricu 《International journal of molecular sciences》2014,15(5):8169-8185
Almost all tumors are composed of a heterogeneous cell population, making them difficult to treat. A small cancer stem cell population with a low proliferation rate and a high tumorigenic potential is thought to be responsible for cancer development, metastasis and resistance to therapy. Stem cells were reported to be involved in both normal development and carcinogenesis, some molecular mechanisms being common in both processes. No less controversial, stem cells are considered to be important in treatment of malignant diseases both as targets and drug carriers. The efforts to understand the role of different signalling in cancer stem cells requires in depth knowledge about the mechanisms that control their self-renewal, differentiation and malignant potential. The aim of this paper is to discuss insights into cancer stem cells historical background and to provide a brief review of the new therapeutic strategies for targeting cancer stem cells. 相似文献
38.
39.
Agent-Oriented Supply-Chain Management 总被引:43,自引:0,他引:43
Mark S. Fox Mihai Barbuceanu Rune Teigen 《International Journal of Flexible Manufacturing Systems》2000,12(2-3):165-188
The supply chain is a worldwide network of suppliers, factories, warehouses, distribution centers, and retailers through which raw materials are acquired, transformed, and delivered to customers. In recent years, a new software architecture for managing the supply chain at the tactical and operational levels has emerged. It views the supply chain as composed of a set of intelligent software agents, each responsible for one or more activities in the supply chain and each interacting with other agents in the planning and execution of their responsibilities. This paper investigates issues and presents solutions for the construction of such an agent-oriented software architecture. The approach relies on the use of an agent building shell, providing generic, reusable, and guaranteed components and services for communicative-act-based communication, conversational coordination, role-based organization modeling, and others. Using these components, we show two nontrivial agent-based supply-chain architectures able to support complex cooperative work and the management of perturbation caused by stochastic events in the supply chain. 相似文献
40.
Mihai Nedelcu 《Thin》2010
The generalised beam theory (GBT) provides a general solution for the linear/non-linear analysis of prismatic thin-walled structures, using bar elements capable of describing the cross-section rigid-body motions and distortions. Nowadays GBT is fully developed for thin-walled members having a large variety of constant cross-sections. This paper provides the extension of GBT for the special case of thin-walled members with variable open cross-section and the limits of its applicability. 相似文献