Evaluating the Network System Corporation Data Exchange Unit Performance under AIX/370

This report presents the results of tests run to evaluate the performance of Network Systems Corporation's Data Exchange Unit (DXU) channel-to-FDDI interface.http://deepblue.lib.umich.edu/bitstream/2027.42/107957/1/citi-tr-92-2.pd

A common distributed language approach to software integration

An important objective in software integration is the development of techniques to allow programs written in different languages to function together. Several approaches are discussed toward achieving this objective and the Common Distributed Language Approach is presented as the approach of choice

Measuring IFS AIX/370 File Server Performance in LPAR Mode

http://deepblue.lib.umich.edu/bitstream/2027.42/107966/1/citi-tr-91-2.pd

Performance Modeling of the PeopleSoft Multi-Tier Remote Computing Architecture

Complex client-server configurations being designed today require a new and closely coordinated approach to analytic modeling and measurement. A closed queuing network model for a two-tiered PeopleSoft 6 client-server system with an Oracle database server is demonstrated using a new performance modeling tool that applies mean value analysis. The focus of this work is on the measurement and modeling of the PeopleSoft architecture to provide useful capacity planning insights for an actual large-scale university-wide deployment. A testbed and database exerciser are then developed to measure model parameters and perform the initial validation tests. The testbed also provides preliminary test data on a proposed three-tiered deployment architecture that includes the Citrix WinFrame environment as an intermediate level between the client and the Oracle server.http://deepblue.lib.umich.edu/bitstream/2027.42/107929/1/citi-tr-97-5.pd

Top mass dependent alpha_s^3 corrections to B-meson mixing in the MSSM

We compute the top mass dependent NLO strong interaction matching conditions to the Delta F=2 effective Hamiltonian in the general MSSM. We study the relevance of such corrections, comparing its size with that of previously known NLO corrections in the limit mt->0, in scenarios with degeneracy, alignment, and hierarchical squarks. We find that, while these corrections are generally small, there are regions in the parameter space where the contributions to the Wilson coefficients C1 and C4 could partially overcome the expected suppression m_t/M_SUSY.Comment: 15 pages, 6 figure

Hierarchical decomposition and simulation of manufacturing cells using Ada

A useful tool in the development of flexible automation is a system description language which can generate a complete func tional description of a manufacturing cell of arbitrary complexity. We propose a description system based on the concept of hierar chical decomposition utilizing the Ada programming language in conjunction with established diagrammatical decomposition methods. The distinguishing aspect of our work is that it takes advantage of certain features of Ada (such as type checking) to create a description that can be automatically verified for con sistency Simulation is often an indispensable tool in the develop ment of manufacturing systems. We show how a simulation of the operation of the manufacturing cell can be embedded in its description. Finally, we apply the methodology to a specific instance of a manufacturing cell.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68498/2/10.1177_003754978604600402.pd

Model-independent extraction of ∣Vtq∣|V_{tq}| matrix elements from top-quark measurements at hadron colliders

Current methods to extract the quark-mixing matrix element $|V_{tb}|$ from single-top production measurements assume that $|V_{tb}|\gg |V_{td}|, |V_{ts}|$: top quarks decay into $b$ quarks with 100% branching fraction, s-channel single-top production is always accompanied by a $b$ quark and initial-state contributions from $d$ and $s$ quarks in the $t$-channel production of single top quarks are neglected. Triggered by a recent measurement of the ratio $R=\frac{|V_{tb}|^{2}}{|V_{td}|^{2}+|V_{ts}|^{2}+|V_{tb}|^{2}}=0.90 \pm 0.04$ performed by the D0 collaboration, we consider a $|V_{tb}|$ extraction method that takes into account non zero d- and s-quark contributions both in production and decay. We propose a strategy that allows to extract consistently and in a model-independent way the quark mixing matrix elements $|V_{td}|$, $|V_{ts}|$, and $|V_{tb}|$ from the measurement of $R$ and from single-top measured event yields. As an illustration, we apply our method to the Tevatron data using a CDF analysis of the measured single-top event yield with two jets in the final state one of which is identified as a $b$-quark jet. We constrain the $|V_{tq}|$ matrix elements within a four-generation scenario by combining the results with those obtained from direct measurements in flavor physics and determine the preferred range for the top-quark decay width within different scenarios.Comment: 36 pages, 17 figure

Theoretical and Phenomenological Constraints on Form Factors for Radiative and Semi-Leptonic B-Meson Decays

We study transition form factors for radiative and rare semi-leptonic B-meson decays into light pseudoscalar or vector mesons, combining theoretical constraints and phenomenological information from Lattice QCD, light-cone sum rules, and dispersive bounds. We pay particular attention to form factor parameterisations which are based on the so-called series expansion, and study the related systematic uncertainties on a quantitative level. In this context, we also provide the NLO corrections to the correlation function between two flavour-changing tensor currents, which enters the unitarity constraints for the coefficients in the series expansion.Comment: 52 pages; v2: normalization error in (29ff.) corrected, conclusion about relevance of unitarity bounds modified; form factor fits unaffected; references added; v3: discussion on truncation of series expansion added, matches version to be published in JHEP; v4: corrected typos in Tables 5 and

Intermediate-mass dilepton spectra and the role of secondary hadronic processes in heavy-ion collisions

We carry out a study of intermediate-mass (between 1 and 2.5 GeV) dilepton spectra from hadronic interactions in heavy-ion collisions. The processes considered are $\pi\pi\to l{\bar l}$, $\pi\rho\to l{\bar l}$, $\pi a_1\to l{\bar l}$, $\pi\omega\to l{\bar l}$, $K{\bar K}\to l{\bar l}$, and $K{\bar K^*}+c.c \to l{\bar l}$. The elementary cross sections for those are obtained from chiral Lagrangians involving pseudoscalar, vector, and axial-vector mesons. The respective electromagnetic form factors are determined by fitting to experimental data for the reverse processes of $e^+e^-\to hadrons$. Based on this input we calculate cross sections and thermal dilepton emission rates and compare our results with those from other approaches. Finally we use these elementary cross sections with a relativistic transport model and calculate dilepton spectra in S+W collisions at SPS energies. The comparison of our results with experimental data from the HELIOS-3 collaboration indicates the importance of the secondary hadronic contributions to the intermediate-mass dilepton spectra.Comment: 25 pages, including 20 postscript figure

Charmless Bs→PP,PV,VVB_s\to PP, PV, VV Decays Based on the six-quark Effective Hamiltonian with Strong Phase Effects II

We provide a systematic study of charmless $B_s \to PP, PV, VV$ decays ($P$ and $V$ denote pseudoscalar and vector mesons, respectively) based on an approximate six-quark operator effective Hamiltonian from QCD. The calculation of the relevant hard-scattering kernels is carried out, the resulting transition form factors are consistent with the results of QCD sum rule calculations. By taking into account important classes of power corrections involving "chirally-enhanced" terms and the vertex corrections as well as weak annihilation contributions with non-trivial strong phase, we present predictions for the branching ratios and CP asymmetries of $B_s$ decays into PP, PV and VV final states, and also for the corresponding polarization observables in VV final states. It is found that the weak annihilation contributions with non-trivial strong phase have remarkable effects on the observables in the color-suppressed and penguin-dominated decay modes. In addition, we discuss the SU(3) flavor symmetry and show that the symmetry relations are generally respected