The Lure Of Regional Solutions: A Realistic Option Or Escapism?

Depending on the nature and importance of disputes, there is a need for either bilateral or unilateral use of global and regional organizations. In spite of the convenience of using regional organizations in solving regional disputes, the growing importance and awareness of the global instrument cannot be minimized

Speaking indirectly : theories of non-literal speech in Indian philosophy

textHow do hearers recognize when someone is speaking figuratively, and how do they recover the content--whatever it is--of an utterance? "Speaking Indirectly" explores this question in Indian philosophy, showing along the way that it is a helpful conversation partner with Western philosophy of language. Focusing on the debate between ninth-century Indian philosophers Mukulabhatt̤a and Ānandavardhana about competing explanations of non-literal meaning, I argue that Mukulabhatt̤a's proposal can be understood in the spirit of Gricean pragmatics, and is broadly successful. I also show that he tacitly appeals to reasoning known as arthāpatti to explain the interpretive process, a process which I conclude is a version of inference to the best explanation. I also employ contemporary conceptual tools, such as the theory of sort-shifting, to illustrate the plausibility of Mukulabhatt̤a's analysis of non-literal speech. A significant aspect of my dissertation is a new, philosophically informed, English translation of Mukulabhatt̤a's Sanskrit text, the Abhidhā-vṛtta-mātṛkā (Fundamentals of the Communicative Function).Philosoph

Eigenfunction Statistics on Quantum Graphs

We investigate the spatial statistics of the energy eigenfunctions on large quantum graphs. It has previously been conjectured that these should be described by a Gaussian Random Wave Model, by analogy with quantum chaotic systems, for which such a model was proposed by Berry in 1977. The autocorrelation functions we calculate for an individual quantum graph exhibit a universal component, which completely determines a Gaussian Random Wave Model, and a system-dependent deviation. This deviation depends on the graph only through its underlying classical dynamics. Classical criteria for quantum universality to be met asymptotically in the large graph limit (i.e. for the non-universal deviation to vanish) are then extracted. We use an exact field theoretic expression in terms of a variant of a supersymmetric sigma model. A saddle-point analysis of this expression leads to the estimates. In particular, intensity correlations are used to discuss the possible equidistribution of the energy eigenfunctions in the large graph limit. When equidistribution is asymptotically realized, our theory predicts a rate of convergence that is a significant refinement of previous estimates. The universal and system-dependent components of intensity correlation functions are recovered by means of an exact trace formula which we analyse in the diagonal approximation, drawing in this way a parallel between the field theory and semiclassics. Our results provide the first instance where an asymptotic Gaussian Random Wave Model has been established microscopically for eigenfunctions in a system with no disorder.Comment: 59 pages, 3 figure

Reducing Uncertainty in Technology Selection for Long Life Cycle Engineering Designs

The best capabilities are usually achieved by having the latest technologies in defense systems. However, including the new, usually immature, technologies in a system design does not always easily result in achieving the capabilities at the right level, at an affordable cost, and in a timely manner. Many programs have suffered from immature technologies as cost overruns, late or no deliveries, and poor performance levels. Another impact of technology selection appears as obsolescence after the deployment of systems, or even before the deployment of the system. As the technologies of a system become obsolete, the cost of maintaining the system increases. Defense systems, which have longer sustainment life cycles, are more vulnerable to obsolescence of technologies. While obsolete technologies increase the cost of maintaining the military systems, they also impact the level of the superiority of the capabilities. In the current literature, several approaches have been proposed by different authors to address either the immature technology risk or the technology obsolescence risk. This study will make an effort to develop an approach which addresses the issue of technology selection for long life cycle defense systems that consider both the feasibility risk of immature technologies and obsolescence risk of technologies

Crystal properties of eigenstates for quantum cat maps

Using the Bargmann-Husimi representation of quantum mechanics on a torus phase space, we study analytically eigenstates of quantized cat maps. The linearity of these maps implies a close relationship between classically invariant sublattices on the one hand, and the patterns (or `constellations') of Husimi zeros of certain quantum eigenstates on the other hand. For these states, the zero patterns are crystals on the torus. As a consequence, we can compute explicit families of eigenstates for which the zero patterns become uniformly distributed on the torus phase space in the limit $\hbar\to 0$. This result constitutes a first rigorous example of semi-classical equidistribution for Husimi zeros of eigenstates in quantized one-dimensional chaotic systems.Comment: 43 pages, LaTeX, including 7 eps figures Some amendments were made in order to clarify the text, mainly in the 4 first sections. Figures are unchanged. To be published in: Nonlinearit

Discovery of an exosite on the SOCS2-SH2 domain that enhances SH2 binding to phosphorylated ligands

Suppressor of cytokine signaling (SOCS)2 protein is a key negative regulator of the growth hormone (GH) and Janus kinase (JAK)-Signal Transducers and Activators of Transcription (STAT) signaling cascade. The central SOCS2-Src homology 2 (SH2) domain is characteristic of the SOCS family proteins and is an important module that facilitates recognition of targets bearing phosphorylated tyrosine (pTyr) residues. Here we identify an exosite on the SOCS2-SH2 domain which, when bound to a non-phosphorylated peptide (F3), enhances SH2 affinity for canonical phosphorylated ligands. Solution of the SOCS2/F3 crystal structure reveals F3 as an α-helix which binds on the opposite side of the SH2 domain to the phosphopeptide binding site. F3:exosite binding appears to stabilise the SOCS2-SH2 domain, resulting in slower dissociation of phosphorylated ligands and consequently, enhances binding affinity. This biophysical enhancement of SH2:pTyr binding affinity translates to increase SOCS2 inhibition of GH signaling

Systems Biology Markup Language (SBML) Level 3 Package: Distributions, Version 1, Release 1

Biological models often contain elements that have inexact numerical values, since they are based on values that are stochastic in nature or data that contains uncertainty. The Systems Biology Markup Language (SBML) Level 3 Core specification does not include an explicit mechanism to include inexact or stochastic values in a model, but it does provide a mechanism for SBML packages to extend the Core specification and add additional syntactic constructs. The SBML Distributions package for SBML Level 3 adds the necessary features to allow models to encode information about the distribution and uncertainty of values underlying a quantity

Approach to ergodicity in quantum wave functions

According to theorems of Shnirelman and followers, in the semiclassical limit the quantum wavefunctions of classically ergodic systems tend to the microcanonical density on the energy shell. We here develop a semiclassical theory that relates the rate of approach to the decay of certain classical fluctuations. For uniformly hyperbolic systems we find that the variance of the quantum matrix elements is proportional to the variance of the integral of the associated classical operator over trajectory segments of length $T_H$, and inversely proportional to $T_H^2$, where $T_H=h\bar\rho$ is the Heisenberg time, $\bar\rho$ being the mean density of states. Since for these systems the classical variance increases linearly with $T_H$, the variance of the matrix elements decays like $1/T_H$. For non-hyperbolic systems, like Hamiltonians with a mixed phase space and the stadium billiard, our results predict a slower decay due to sticking in marginally unstable regions. Numerical computations supporting these conclusions are presented for the bakers map and the hydrogen atom in a magnetic field.Comment: 11 pages postscript and 4 figures in two files, tar-compressed and uuencoded using uufiles, to appear in Phys Rev E. For related papers, see http://www.icbm.uni-oldenburg.de/icbm/kosy/ag.htm

How Chaotic is the Stadium Billiard? A Semiclassical Analysis

The impression gained from the literature published to date is that the spectrum of the stadium billiard can be adequately described, semiclassically, by the Gutzwiller periodic orbit trace formula together with a modified treatment of the marginally stable family of bouncing ball orbits. I show that this belief is erroneous. The Gutzwiller trace formula is not applicable for the phase space dynamics near the bouncing ball orbits. Unstable periodic orbits close to the marginally stable family in phase space cannot be treated as isolated stationary phase points when approximating the trace of the Green function. Semiclassical contributions to the trace show an $\hbar$ - dependent transition from hard chaos to integrable behavior for trajectories approaching the bouncing ball orbits. A whole region in phase space surrounding the marginal stable family acts, semiclassically, like a stable island with boundaries being explicitly $\hbar$-dependent. The localized bouncing ball states found in the billiard derive from this semiclassically stable island. The bouncing ball orbits themselves, however, do not contribute to individual eigenvalues in the spectrum. An EBK-like quantization of the regular bouncing ball eigenstates in the stadium can be derived. The stadium billiard is thus an ideal model for studying the influence of almost regular dynamics near marginally stable boundaries on quantum mechanics.Comment: 27 pages, 6 figures, submitted to J. Phys.