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Development of a Personalized Quantitative Faculty Annual Evaluation System
Faculty annual evaluation is critical for faculty career
development and department success. Our department
developed a quantitative faculty evaluation metrics system
that is more objective, consistent, flexible, personalized,
transparent, and dynamic scoring system. We have
implemented the system for 2 years and the outcomes are
very encouraging in promoting faculty and department
success.Cockrell School of Engineerin
An Iterative Scheme for Leverage-based Approximate Aggregation
The current data explosion poses great challenges to the approximate
aggregation with an efficiency and accuracy. To address this problem, we
propose a novel approach to calculate the aggregation answers with a high
accuracy using only a small portion of the data. We introduce leverages to
reflect individual differences in the samples from a statistical perspective.
Two kinds of estimators, the leverage-based estimator, and the sketch estimator
(a "rough picture" of the aggregation answer), are in constraint relations and
iteratively improved according to the actual conditions until their difference
is below a threshold. Due to the iteration mechanism and the leverages, our
approach achieves a high accuracy. Moreover, some features, such as not
requiring recording the sampled data and easy to extend to various execution
modes (e.g., the online mode), make our approach well suited to deal with big
data. Experiments show that our approach has an extraordinary performance, and
when compared with the uniform sampling, our approach can achieve high-quality
answers with only 1/3 of the same sample size.Comment: 17 pages, 9 figure
BaFe2Se2O as an Iron-Based Mott Insulator with Antiferromagnetic Order
A new compound with a quasi-two-dimensional array of FeSe3O tetrahedra and an
orthorombic structure, namely BaFe2Se2O, has been successfully fabricated.
Experimental results show that this compound is an insulator and has an
antiferromagnetic (AF) transition at 240 K. Band structure calculation reveals
the narrowing of Fe 3d bands near the Fermi energy, which leads to the
localization of magnetism and the Mott insulating behavior. The large distances
between the Fe atoms perhaps are responsible for the characters. Linear
response calculation further indicates a strong in-plane AF exchange , this
can account for the enhanced magnetic susceptibility (which has a maximum at
about 450 K) above the Neel temperature.Comment: submitted to PRL on 2 May 2012, resubmitted to PRB on 31 May 2012,
and accepted by PRB on 5 July 201
KIPSE1: A Knowledge-based Interactive Problem Solving Environment for data estimation and pattern classification
A knowledge-based interactive problem solving environment called KIPSE1 is presented. The KIPSE1 is a system built on a commercial expert system shell, the KEE system. This environment gives user capability to carry out exploratory data analysis and pattern classification tasks. A good solution often consists of a sequence of steps with a set of methods used at each step. In KIPSE1, solution is represented in the form of a decision tree and each node of the solution tree represents a partial solution to the problem. Many methodologies are provided at each node to the user such that the user can interactively select the method and data sets to test and subsequently examine the results. Otherwise, users are allowed to make decisions at various stages of problem solving to subdivide the problem into smaller subproblems such that a large problem can be handled and a better solution can be found
CHARACTERIZATION OF HETEROGENEOUS CATALYSTS USING ADVANCED TRANSMISSION ELECTRON MICROSCOPY TECHNIQUES
Chang Wan Han, Ph. D., Purdue University, December 2016. Characterization of Heterogeneous Catalysts using Advanced Transmission Electron Microscopy Techniques. Major Professor: Volkan Ortalan
Radiative Neutrino Mass with Dark matter: From Relic Density to LHC Signatures
In this work we give a comprehensive analysis on the phenomenology of a
specific dark matter (DM) model in which neutrino mass is
induced at two loops by interactions with a DM particle that can be a complex
scalar or a Dirac fermion. Both the DM properties in relic density and direct
detection and the LHC signatures are examined in great detail, and indirect
detection for gamma-ray excess from the Galactic Center is also discussed
briefly. On the DM side, both semi-annihilation and co-annihilation processes
play a crucial role in alleviating the tension of parameter space between relic
density and direct detection. On the collider side, new decay channels
resulting from particles lead to distinct signals at LHC.
Currently the trilepton signal is expected to give the most stringent bound for
both scalar and fermion DM candidates, and the signatures of fermion DM are
very similar to those of electroweakinos in simplified supersymmetric models.Comment: 40 pages, 24 figure
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