103,192 research outputs found
Substantially Justified? The U.S. Government’s Use of Name-Check Technologies in Naturalization Procedures
The U.S. Citizenship and Immigration Services relies upon the Federal Bureau of Investigation to administer the National Name Check Program, which conducts background checks on applicants for naturalization. Backlogs have led to long delays for aspiring citizens and significant legal problems for the government.
This iBrief examines the First Circuit’s ruling in Aronov v. Napolitano that an eighteen-month delay in adjudicating a naturalization application was substantially justified. While the government’s inefficiency can be explained partly by an understaffed bureaucracy, overwhelming evidence suggests that these problems are exacerbated by a technological infrastructure that is ill-equipped to handle the scope of the backlog. This iBrief argues that the government should be held liable for its failures; and that long-overdue technological improvements should be implemented to prevent these issues from recurring in the future
Determinations of |V_ub| and |V_cb| from measurements of B -> X_u,c\ell\nu differential decay rates
Methods are described in the framework of light-cone expansion which allow
one to determine the Cabibbo-Kobayashi-Maskawa matrix elements |V_ub| and
|V_cb| from measurements of the differential decay rates as a function of the
scaling variables in the inclusive semileptonic decays of B mesons. By these
model-independent methods the dominant hadronic uncertainties can be avoided
and the B -> X_u\ell\nu decay can be very efficiently differentiated from the B
-> X_c\ell\nu decay, which may lead to precise determinations of |V_ub| and
|V_cb|.Comment: 11 pages, 2 figures, version as published in Mod. Phys. Lett. A, more
discussion, references added, title chang
A flexible mandatory access control policy for XML databases
A flexible mandatory access control policy (MAC) for XML
databases is presented in this paper. The label type and label
access policy can be defined according to the requirements of
applications. In order to preserve the integrity of data in XML
databases, a constraint between a read access rule and a write
access rule in label access policy is introduced. Rules for label
assignment and propagation are proposed to alleviate the
workload of label assignment. Also, a solution for resolving
conflicts of label assignments is proposed. At last, operations for
implementation of the MAC policy in a XML database are
illustrated
Assessing and Remedying Coverage for a Given Dataset
Data analysis impacts virtually every aspect of our society today. Often,
this analysis is performed on an existing dataset, possibly collected through a
process that the data scientists had limited control over. The existing data
analyzed may not include the complete universe, but it is expected to cover the
diversity of items in the universe. Lack of adequate coverage in the dataset
can result in undesirable outcomes such as biased decisions and algorithmic
racism, as well as creating vulnerabilities such as opening up room for
adversarial attacks.
In this paper, we assess the coverage of a given dataset over multiple
categorical attributes. We first provide efficient techniques for traversing
the combinatorial explosion of value combinations to identify any regions of
attribute space not adequately covered by the data. Then, we determine the
least amount of additional data that must be obtained to resolve this lack of
adequate coverage. We confirm the value of our proposal through both
theoretical analyses and comprehensive experiments on real data.Comment: in ICDE 201
OWNERSHIP AND INDUSTRIAL POLLUTION CONTROL: EVIDENCE FROM CHINA
This study explores the differences in pollution control performances of industrial enterprises with various ownerships in China - State owned (SOE), collectively or community owned (COE), privately owned (POE), foreign directly invested (FDI) companies as well as joint ventures. A survey was conducted of approximately 1000 industrial firms in three provinces in China, which collects the detailed firm-level information in the year of 1999. Personal interviews of enterprises managers were also conducted in these samples, and subjective information was collected. Analyses have been performed on the differences in receiving and reacting to environmental regulatory enforcement, community pressure, environmental services, and internal environmental management among different ownerships. The determinants of the industrial pollution emissions in China are identified in the econometrical analyses. The results show that FDI and COE have better environmental performances, while SOEs and the POEs in China are the worst.Environmental Economics and Policy,
Nonclassical effects in two-photon interference experiments: event-by-event simulations
It is shown that both the visibility predicted for
two-photon interference experiments with two independent
sources\textcolor{black}{, like the Hanbury Brown-Twiss experiment,} and the
visibility predicted for two-photon interference experiments
with a parametric down-conversion source\textcolor{black}{, like the
Ghosh-Mandel experiment,} can be explained \textcolor{black}{by a discrete
event simulation. This simulation approach reproduces the statistical
distributions of wave theory not by requiring the knowledge of the solution of
the wave equation of the whole system but by generating detection events
one-by-one according to an unknown distribution.} There is thus no need to
invoke quantum theory to explain the so-called nonclassical effects in the
interference of signal and idler photons in parametric down conversion. Hence,
a revision of the commonly accepted criterion of the nonclassical nature of
light\textcolor{black}{, ,} is called for.Comment: arXiv admin note: substantial text overlap with arXiv:1208.2368,
arXiv:1006.172
Bayesian feedback versus Markovian feedback in a two-level atom
We compare two different approaches to the control of the dynamics of a
continuously monitored open quantum system. The first is Markovian feedback as
introduced in quantum optics by Wiseman and Milburn [Phys. Rev. Lett. {\bf 70},
548 (1993)]. The second is feedback based on an estimate of the system state,
developed recently by Doherty {\em et al.} [Phys. Rev. A {\bf 62}, 012105
(2000)]. Here we choose to call it, for brevity, {\em Bayesian feedback}. For
systems with nonlinear dynamics, we expect these two methods of feedback
control to give markedly different results. The simplest possible nonlinear
system is a driven and damped two-level atom, so we choose this as our model
system. The monitoring is taken to be homodyne detection of the atomic
fluorescence, and the control is by modulating the driving. The aim of the
feedback in both cases is to stabilize the internal state of the atom as close
as possible to an arbitrarily chosen pure state, in the presence of inefficient
detection and other forms of decoherence. Our results (obtain without recourse
to stochastic simulations) prove that Bayesian feedback is never inferior, and
is usually superior, to Markovian feedback. However it would be far more
difficult to implement than Markovian feedback and it loses its superiority
when obvious simplifying approximations are made. It is thus not clear which
form of feedback would be better in the face of inevitable experimental
imperfections.Comment: 10 pages, including 3 figure
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