Variability and Evolution in Systems of Systems

In this position paper (1) we discuss two particular aspects of Systems of Systems, i.e., variability and evolution. (2) We argue that concepts from Product Line Engineering and Software Evolution are relevant to Systems of Systems Engineering. (3) Conversely, concepts from Systems of Systems Engineering can be helpful in Product Line Engineering and Software Evolution. Hence, we argue that an exchange of concepts between the disciplines would be beneficial.Comment: In Proceedings AiSoS 2013, arXiv:1311.319

A Possible Signal for QGP Formation from the Minimum-Bias Data of Relativistic Large Heavy Ion Collisions

It is argued that the experimentally observed strong upward-bending of the logarithm of factorial moments versus that of phase space partition number in the higher-dimensional phase space of nucleus-nucleus collisions is due to the superposition of elementary collision processes in these collisions. A direct implication of this observation is that, at high enough energy and/or density, when the produced particles from individual elementary processes are melted into a unique system the above-mentioned superposition effect will disappear and the factorial moments will not be strongly upward-bending any more. So, the disappearance of strong upward-bending of higher-dimensional factorial moments in heavy ion collision may be taken as a signal for the formation of a unique system, or QGP, in this collision.Comment: 5 pages 3 Postscript figures, Late

Феноменологические модели образования натрубных отложений в котлах

В соответствии с существующей классификацией наружных загрязнений поверхностей нагрева котлов систематизированы представления, необходимые для составления физических моделей процессов и для обоснования натурных и лабораторных экспериментов. Выделена роль теплофизических свойств и, в частности, теплопроводности, в эволюции слоевой структуры, показаны основные физические и химические факторы, определяющие развитие отложений

Soft photon anomaly and gauge/string duality

Motivated by the recent DELPHI report on the anomalous photon production in e^+e^- annihilation, we exactly calculate the inclusive cross section of soft photons in the strong coupling limit of N=4 super Yang-Mills. We find that the energy distribution is that of the Bremsstrahlung, while the angular distribution is spherical. Our result elucidates a new non-perturbative source of soft photons not associated with the final state hadronic Bremsstrahlung.Comment: 22 page

A Transient New Coherent Condition of Matter: The Signal for New Physics in Hadronic Diffractive Scattering

We demonstrate the existence of an anomalous structure in the data on the diffractive elastic scattering of hadrons at high energies and small momentum transfer. We analyze five sets of experimental data on $p(\overline{p})-p$ scattering from five different experiments with colliding beams, ranging from the first-- and second--generation experiments at $\sqrt{s} = 53$ GeV to the most recent experiments at 546 GeV and at 1800 GeV. All of the data sets exhibit a localized anomalous structure in momentum transfer. We represent the anomalous behavior by a phenomenological formula. This is based upon the idea that a transient coherent condition of matter occurs in some of the intermediate inelastic states which give rise, via unitarity, to diffractive elastic scattering. The Fourier--Bessel transform into momentum--transfer space of a spatial oscillatory behavior of matter in the impact--parameter plane results in a small piece of the diffractive amplitude which exhibits a localized anomalous behavior near a definite value of $-t$. In addition, we emphasize possible signals coming directly from such a new condition of matter that may be present in current experiments on inelastic processes.Comment: 25 pages, LaTeX (12 figures, not included). A complete postscript file (except figures 1 and 11, which are available upon request) is available via anonymous ftp at ttpux2.physik.uni-karlsruhe.de (129.13.102.139) as /ttp94-03 /ttp94-03.ps, Local preprint# TTP94-03 (March 1994

Ethnicity, voter alignment and political party affiliation - an African case: Zambia

Conventional wisdom holds that ethnicity provides the social cleavage for voting behav-iour and party affiliation in Africa. Because this is usually inferred from aggregate data of national election results, it might prove to be an ecological fallacy. The evidence based on individual data from an opinion survey in Zambia suggests that ethnicity matters for voter alignment and even more so for party affiliation, but it is certainly not the only factor. The analysis also points to a number of qualifications which are partly methodology-related. One is that the degree of ethnic voting can differ from one ethno-political group to the other depending on various degrees of ethnic mobilisation. Another is that if smaller eth-nic groups or subgroups do not identify with one particular party, it is difficult to find a significant statistical correlation between party affiliation and ethnicity - but that does not prove that they do not affiliate along ethnic lines.Wahlverhalten und Mitgliedschaft in politischen Parteien Afrikas ist nur wenig untersucht worden. Gewöhnlich wird argumentiert, dass Ethnizität als soziale Konfliktlinie das Wahlverhalten und die Parteienmitgliedschaft strukturiert. Da dieses Argument auf hoch aggregierten Wahldaten beruht, kann hier ein ökologischer Fehlschuss vorliegen. Die vorliegende Analyse beruht deshalb auf individuellen Umfragedaten aus Sambia. Das Ergebnis ist, dass Ethnizität tatsächlich eine Rolle für das Wahlverhalten und die Parteienmitgliedschaft spielt, aber keineswegs den einzigen Erklärungsfaktor darstellt. Die Analyse offenbart zudem eine Reihe von Einschränkungen und Qualifizierungen, die teilweise methodischer Natur sind. Eine ist, dass ethnisches Wahlverhalten und Parteienmitgliedschaft von einer ethnischen Gruppe zur anderen unterschiedlich ist, dass, wenn sich kleinere ethnische Gruppen oder Untergruppen mit keiner Partei identifizieren, es schwierig wird, statistisch signifikante Korrelationen zu finden - was indessen noch nicht beweist, dass Ethnizität keine Rolle spielt

Soft Photons in Hadron-Hadron Collisions: Synchrotron Radiation from the QCD Vacuum?

We discuss the production of soft photons in high energy hadron-hadron collisions. We present a model where quarks and antiquarks in the hadrons emit ``synchrotron light'' when being deflected by the chromomagnetic fields of the QCD vacuum, which we assume to have a nonperturbative structure. This gives a source of prompt soft photons with frequencies $\omega <= 300 MeV$ in the c.m. system of the collision in addition to hadronic bremsstrahlung. In comparing the frequency spectrum and rate of ``synchrotron'' photons to experimental results we find some supporting evidence for their existence. We make an exclusive--inclusive connection argument to deduce from the ``synchrotron'' effect a behaviour of the neutron electric formfactor $G_E^n(Q^2)$ proportional to $(Q^2)^{1/6}$ for $Q^2 < 20 fm^{-2}$. We find this to be consistent with available data. In our view, soft photon production in high energy hadron-hadron and lepton-hadron collisions as well as the behaviour of electromagnetic hadron formfactors for low $Q^2$ are thus sensitive probes of the nonperturbative structure of the QCD vacuum.Comment: Heidelberg preprint HD-THEP-94-36, 31 pages, LaTeX + ZJCITE.sty (included), 12 figures appended as uuencoded compressed ps-fil

Worldline Approach to Forward and Fixed Angle fermion-fermion Scattering in Yang-Mills Theories at High Energies

Worldline techniques are employed to study the general behaviour of the fermion-fermion collision amplitude at very high energies in a non-abelian gauge field theory for the forward and fixed angle scattering cases. A central objective of this work is to demonstrate the simplicity by which the worldline methodology isolates that sector of the full theory which carries the soft physics, relevant to each process. Anomalous dimensions pertaining to a given soft sector are identified and subseuently used to facilitate the renormalization group running of the respective four point functions. Gluon reggeization is achieved for forward, while Sudakov suppression is established for fixed angle scattering.Comment: 28 pages, 10 figures in three file

Capturing the requirements for multiple user interfaces

non-peer-reviewedIn this paper we describe MANTRA, a model-driven approach for the development of multiple consistent user interfaces for one application. The common requirements of all these user interfaces are captured in an abstract UI model (AUI) which is annotated with constraints on the dialogue flow. We exemplify all further steps along a well known application scenario in which a user queries train connections from a simple timetable service. We consider in particular how the user interface can be adapted on the AUI level by deriving and tailoring dialogue structures which take into account constraints imposed by front-end platforms or inexperienced users. With this input we use model transformations to derive concrete, platform-specific UI models (CUI). These can be used to generate implementation code for several UI platforms including GUI applications, dynamic websites and mobile applications. The user interfaces are integrated with a multi tier application by referencing WSDL-based (Web Service Description Language) interface descriptions. Finally, we discuss how our approach can be extended to include voice interfaces. This imposes special challenges as these interfaces tend to be structurally different from visual platforms and have to be specified using speech-input grammars