128,253 research outputs found
ANALISIS SERVICE PACKAGE PADA LEMBAGA BIMBINGAN BELAJAR DI KOTA MALANG
This research was conducted at a Tutoring Institute in Malang City. This study aims to determine the service package and service package results at Tutoring Institutions in Malang City. The respondents of this study were consumers from Ganesha Operation, Neutron, and Brain Academy. The analysis tools used are scale range and cluster k-means analysis with calculations using spss. The results showed that consumers at the Tutoring Institute pay attention to the service package and there are three consumer clusters at the Tutoring Institute. The attributes used are supporting facility, facilitating goods, information, explicit service, and implicit service. The advice given to the company is to continue to improve the existing service package at the Tutoring Institut
Isometric Dilations of Representations of Product Systems via Commutants
We construct a weak dilation of a not necessarily unital CP-semigroup to an
E-semigroup acting on the adjointable operators of a Hilbert module with a unit
vector. We construct the dilation in such a way that the dilating E-semigroup
has a pre-assigned product system. Then, making use of the commutant of von
Neumann correspondences, we apply the dilation theorem to proof that covariant
representations of product systems admit isometric dilations.Comment: Switched some definitions directly after theorems in Sect. 1,
included (>6 pp.) introduction to von Neumann correspondences (Sect. 3). To
appear in International Journal of Mathematic
Isospin in Reaction Dynamics. The Case of Dissipative Collisions at Fermi Energies
A key question in the physics of unstable nuclei is the knowledge of the
for asymmetric nuclear matter () away from normal conditions. We
recall that the symmetry energy at low densities has important effects on the
neutron skin structure, while the knowledge in high densities region is crucial
for supernovae dynamics and neutron star properties. The way to probe
such region of the isovector in terrestrial laboratories is through very
dissipative collisions of asymmetric (up to exotic) heavy ions from low to
relativistic energies. A general introduction to the topic is firstly
presented. We pass then to a detailed discussion on the
process as the main dissipative mechanism at the Fermi energies and to the
related isospin dynamics. From Stochastic Mean Field simulations the isospin
effects on all the phases of the reaction dynamics are thoroughly analysed,
from the fast nucleon emission to the mid-rapidity fragment formation up to the
dynamical fission of the residues. Simulations have been performed
with an increasing stiffness of the symmetry term of the .
Some differences have been noticed, especially for the fragment charge
asymmetry. New isospin effects have been revealed from the correlation of
fragment asymmetry with dynamical quantities at the freeze-out time. A series
of isospin sensitive observables to be further measured are finally listed.Comment: 16 pages, 6 figures, Contribution to the 5th Italy-Japan Symposium,
Recent Achievements and Perspectives in Nuclear Physics, Naples Nov.3-7 2004,
World Sci. in press. Latex in WorldSci/proc/styl
Revisiting interval protection, a.k.a. partial cell suppression, for tabular data
The final publication is available at link.springer.comInterval protection or partial cell suppression was introduced in “M. Fischetti, J.-J. Salazar, Partial cell suppression: A new methodology for statistical disclosure control, Statistics and Computing, 13, 13–21, 2003” as a “linearization” of the difficult cell suppression problem. Interval protection replaces some cells by intervals containing the original cell value, unlike in cell suppression where the values are suppressed. Although the resulting optimization problem is still huge—as in cell suppression, it is linear, thus allowing the application of efficient procedures. In this work we present preliminary results with a prototype implementation of Benders decomposition for interval protection. Although the above seminal publication about partial cell suppression applied a similar methodology, our approach differs in two aspects: (i) the boundaries of the intervals are completely independent in our implementation, whereas the one of 2003 solved a simpler variant where boundaries must satisfy a certain ratio; (ii) our prototype is applied to a set of seven general and hierarchical tables, whereas only three two-dimensional tables were solved with the implementation of 2003.Peer ReviewedPostprint (author's final draft
Blind Identification of SIMO Wiener Systems based on Kernel Canonical Correlation Analysis
We consider the problem of blind identification and equalization of
single-input multiple-output (SIMO) nonlinear channels. Specifically, the
nonlinear model consists of multiple single-channel Wiener systems that are
excited by a common input signal. The proposed approach is based on a
well-known blind identification technique for linear SIMO systems. By
transforming the output signals into a reproducing kernel Hilbert space (RKHS),
a linear identification problem is obtained, which we propose to solve through
an iterative procedure that alternates between canonical correlation analysis
(CCA) to estimate the linear parts, and kernel canonical correlation (KCCA) to
estimate the memoryless nonlinearities. The proposed algorithm is able to
operate on systems with as few as two output channels, on relatively small data
sets and on colored signals. Simulations are included to demonstrate the
effectiveness of the proposed technique
Semantic Query Reformulation in Social PDMS
We consider social peer-to-peer data management systems (PDMS), where each
peer maintains both semantic mappings between its schema and some
acquaintances, and social links with peer friends. In this context,
reformulating a query from a peer's schema into other peer's schemas is a hard
problem, as it may generate as many rewritings as the set of mappings from that
peer to the outside and transitively on, by eventually traversing the entire
network. However, not all the obtained rewritings are relevant to a given
query. In this paper, we address this problem by inspecting semantic mappings
and social links to find only relevant rewritings. We propose a new notion of
'relevance' of a query with respect to a mapping, and, based on this notion, a
new semantic query reformulation approach for social PDMS, which achieves great
accuracy and flexibility. To find rapidly the most interesting mappings, we
combine several techniques: (i) social links are expressed as FOAF (Friend of a
Friend) links to characterize peer's friendship and compact mapping summaries
are used to obtain mapping descriptions; (ii) local semantic views are special
views that contain information about external mappings; and (iii) gossiping
techniques improve the search of relevant mappings. Our experimental
evaluation, based on a prototype on top of PeerSim and a simulated network
demonstrate that our solution yields greater recall, compared to traditional
query translation approaches proposed in the literature.Comment: 29 pages, 8 figures, query rewriting in PDM
Quantum Energy Expectation in Periodic Time-Dependent hamiltonians via Green Functions
Let be the Floquet operator of a time periodic hamiltonian .
For each positive and discrete observable (which we call a {\em probe
energy}), we derive a formula for the Laplace time average of its expectation
value up to time in terms of its eigenvalues and Green functions at the
circle of radius . Some simple applications are provided which support
its usefulness.Comment: 31 page
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