752 research outputs found
Probabilistic Analysis and Algorithms for Reconfiguration of Memory Arrays
Coordinated Science Laboratory was formerly known as Control Systems LaboratoryPublication date of November 1990 on the cover of some copies was evidently a typographical error, and May 1990 is the correct date.Semiconductor Research Corporation (SRC) / 89-DP-10
Review of a partial care program for severely emotionally disturbed youth
The need for research on programs for Emotionally Disturbed (ED) children and adolescents is great. The present study examined a partial care program for ED youth in New Jersey. There were 120 subjects in this study. Several characteristics of these subjects were examined – gender, race, age, diagnosis, and family status. The study also examined the subjects\u27 average length of stay in the program.and reasons for being discharged. In addition, the ratio of clients to staff was studied. The data was collected by examining the files of past and present clients to gather the necessary information. Descriptive statistics were used to analyze the results. The majority of the subjects were African American males between the ages of 12 and 15 years. Most were either diagnosed Conduct Disorder or Oppositional Defiant Disorder and most lived with a single parent. The overall length of stay for the subjects was 8 months. Most of them were discharged due to refusal of service or to another placement. The ratio of clients to staff varied from 6 to 1 to 3 to 1 over the three year period studied
Lazy Checkpoint Coordination for Bounding Rollback Propagation
Coordinated Science Laboratory was formerly known as Control Systems LaboratoryNational Aeronautics and Space Administration / NASA NAG 1-613Department of the Navy managed by the Office of the Chief of Naval Research / N00014-91-J-128
Optimal Message Log Reclamation for Independent Checkpointing
Coordinated Science Laboratory was formerly known as Control Systems LaboratoryNational Aeronautics and Space Administration / NASA NAG 1-613Department of the Navy managed by the Office of the Chief of Naval Research / N00014-91-J-128
TRAPEDS: Producing Traces for Multicomputers via Execution-Driven Simulation
Coordinated Science Laboratory was formerly known as Control Systems LaboratoryNational Aeronautics and Space Administration / NASA NAG-1-613Shell Doctoral FellowshipDigital Faculty Incentives for Excellence Awar
Recoverable Distributed Shared Memory Under Sequential and Relaxed Consistency
Coordinated Science Laboratory was formerly known as Control Systems LaboratoryOffice of Naval Research / N00014-90-J-1270 and N00014-91-J-1283National Aeronautics and Space Administration / NASA NAG 1-61
Analytic Expressions for Singular Vectors of the Superconformal Algebra
Using explicit expressions for a class of singular vectors of the
(untwisted) algebra and following the approach of Malikov-Feigin-Fuchs and
Kent, we show that the analytically extended Verma modules contain two linearly
independent neutral singular vectors at the same grade. We construct this two
dimensional space and we identify the singular vectors of the original Verma
modules. We show that in some Verma modules these expressions lead to two
linearly independent singular vectors which are at the same grade and have the
same charge.Comment: 35 pages, LATE
Countering Quantum Noise with Supplementary Classical Information
We consider situations in which i) Alice wishes to send quantum information
to Bob via a noisy quantum channel, ii) Alice has a classical description of
the states she wishes to send and iii) Alice can make use of a finite amount of
noiseless classical information. After setting up the problem in general, we
focus attention on one specific scenario in which Alice sends a known qubit
down a depolarizing channel along with a noiseless cbit. We describe a protocol
which we conjecture is optimal and calculate the average fidelity obtained. A
surprising amount of structure is revealed even for this simple case which
suggests that relationships between quantum and classical information could in
general be very intricate.Comment: RevTeX, 5 pages, 2 figures Typo in reference 9 correcte
An implementation and performance measurement of the progressive retry technique
This paper describes a recovery technique called progressive retry for bypassing software faults in message-passing applications. The technique is implemented as reusable modules to provide application-level software fault tolerance. The paper describes the implementation of the technique and presents results from the application of progressive retry to two telecommunications systems. the results presented show that the technique is helpful in reducing the total recovery time for message-passing applications
Equilibrium Initialization and Stability of Three-Dimensional Gas Disks
We present a new systematic way of setting up galactic gas disks based on the
assumption of detailed hydrodynamic equilibrium. To do this, we need to specify
the density distribution and the velocity field which supports the disk. We
first show that the required circular velocity has no dependence on the height
above or below the midplane so long as the gas pressure is a function of
density only. The assumption of disks being very thin enables us to decouple
the vertical structure from the radial direction. Based on that, the equation
of hydrostatic equilibrium together with the reduced Poisson equation leads to
two sets of second-order non-linear differential equation, which are easily
integrated to set-up a stable disk. We call one approach `density method' and
the other one `potential method'. Gas disks in detailed balance are especially
suitable for investigating the onset of the gravitational instability. We
revisit the question of global, axisymmetric instability using fully
three-dimensional disk simulations. The impact of disk thickness on the disk
instability and the formation of spontaneously induced spirals is studied
systematically with or without the presence of the stellar potential. In our
models, the numerical results show that the threshold value for disk
instability is shifted from unity to 0.69 for self-gravitating thick disks and
to 0.75 for combined stellar and gas thick disks. The simulations also show
that self-induced spirals occur in the correct regions and with the right
numbers as predicted by the analytic theory.Comment: 17 pages, 10 figures, accepted by MNRA
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