19,189 research outputs found
Q^2 Evolution of the Neutron Spin Structure Moments using a ^3He Target
We have measured the spin structure functions g_1 and g_2 of ^3He in a double-spin experiment by inclusively scattering polarized electrons at energies ranging from 0.862 to 5.058 GeV off a polarized ^3He target at a 15.5° scattering angle. Excitation energies covered the resonance and the onset of the deep inelastic regions. We have determined for the first time the Q^2 evolution of Γ_1(Q^2)=∫_0^1g_1(x,Q^2)dx, Γ_2(Q^2)=∫_0^1g_2(x,Q^2)dx, and d_2(Q^2)=∫_0^1x^2[2g_1(x,Q^2)+3g_2(x,Q^2)]dx for the neutron in the range 0.1 ≤ Q^2 ≤0.9 GeV^2 with good precision. Γ_1(Q^2) displays a smooth variation from high to low Q^2. The Burkhardt-Cottingham sum rule holds within uncertainties and d_2 is nonzero over the measured range
Restructuring databases for knowledge discovery by consolidation and link formation
Databases often inaccurately identify entities of interest. Two operations, consolidation and link formation, which complement the usual machine learning techniques that use similarity-based clustering to discover classifications, are proposed as essential components of KDD systems for certain applications. Consolidation relates identifiers present in a database to a set of real world entities (RWE’s) which are not uniquely identified in the database. Consolidation may also be viewed as a transformation of representation from the identifiers present in the original database to the RWE’s. Link formation constructs structured relationships between consolidated RWE’s through identifiers and events explicitly represented in the database. Consolidation and link formation are easily implemented as index creation in relational database management systems. An operational knowledge discovery system identifies potential money laundering in a database of large cash transactions using consolidation and link formation
Nuclear structure beyond the neutron drip line: the lowest energy states in He via their T=5/2 isobaric analogs in Li
The level structure of the very neutron rich and unbound He nucleus has
been the subject of significant experimental and theoretical study. Many recent
works have claimed that the two lowest energy He states exist with spins
and and widths on the order of hundreds of keV.
These findings cannot be reconciled with our contemporary understanding of
nuclear structure. The present work is the first high-resolution study with low
statistical uncertainty of the relevant excitation energy range in the
He system, performed via a search for the T=5/2 isobaric analog states
in Li populated through He+p elastic scattering. The present data show
no indication of any narrow structures. Instead, we find evidence for a broad
state in He located approximately 3 MeV above the neutron
decay threshold
Effects of seawater and deionized water at 0 to 80 deg C on the flexural properties of a glass/epoxy composite
The effect on the flexural properties of a glass/epoxy composite of immersion in deionized water or seawater at 0, 25, and 80 C for 451 hr was examined. The percent weight gain at 0 and 25 C was low (0.06 to 0.17 percent) and there was no significant change in the flexural properties for these environmental conditions. At 80 C there was a decrease in the flexural strength of 17 and 20 percent in seawater and deionized water, respectively. This is a comparison to control samples exposed to 80 C heat alone. These decreases were found to be nearly reversible once the samples were dried. Optical microscopy did not reveal cracking of the matrix. The flexural modulus was essentially unaffected by exposure to deionized water and seawater at 80 C
“Am I Telling the Story Right?” Poetry, Community, and Trauma
The Hill District of Pittsburgh, Pennsylvania (USA) is a once vibrant community that experienced socioeconomic decline through urban renewal polices and related factors. This article presents poems constructed from interviews with women who considered the Hill District to be their home. Interviews were completed as part of an undergraduate-level community-engaged learning course in collaboration with a local agency. One component of the course was a public reading, during which the poems were shared with members of the community and the University. The poems were created through use of the Listening Guide, a feminist relational method. These emotionally resonant poems, known as I poems, attend to the subjective experience of each participant by focusing on her use of “I” throughout the interview transcripts. While individual in nature, these poems are inseparable from the historical trauma the Hill District has experienced. Seen through the lens of root shock, interpersonal and intergenerational traumas are also the trauma of the Hill District. Poetic inquiry provides an avenue for connecting individual experience with the larger community story
Shortest Path Computation with No Information Leakage
Shortest path computation is one of the most common queries in location-based
services (LBSs). Although particularly useful, such queries raise serious
privacy concerns. Exposing to a (potentially untrusted) LBS the client's
position and her destination may reveal personal information, such as social
habits, health condition, shopping preferences, lifestyle choices, etc. The
only existing method for privacy-preserving shortest path computation follows
the obfuscation paradigm; it prevents the LBS from inferring the source and
destination of the query with a probability higher than a threshold. This
implies, however, that the LBS still deduces some information (albeit not
exact) about the client's location and her destination. In this paper we aim at
strong privacy, where the adversary learns nothing about the shortest path
query. We achieve this via established private information retrieval
techniques, which we treat as black-box building blocks. Experiments on real,
large-scale road networks assess the practicality of our schemes.Comment: VLDB201
Statistics of Oscillator Strengths in Chaotic Systems
The statistical description of oscillator strengths for systems like hydrogen
in a magnetic field is developed by using the supermatrix nonlinear
-model. The correlator of oscillator strengths is found to have a
universal parametric and frequency dependence, and its analytical expression is
given. This universal expression applies to quantum chaotic systems with the
same generality as Wigner-Dyson statistics.Comment: 11 pages, REVTeX3+epsf, two EPS figures. Replaced by the published
version. Minor changes
Structure of 10N in 9C+p resonance scattering
The structure of exotic nucleus 10N was studied using 9C+p resonance
scattering. Two L=0 resonances were found to be the lowest states in 10N. The
ground state of 10N is unbound with respect to proton decay by 2.2(2) or 1.9(2)
MeV depending on the 2- or 1- spin-parity assignment, and the first excited
state is unbound by 2.8(2) MeV.Comment: 6 pages, 4 figures, 1 table, submitted to Phys. Lett.
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