112,677 research outputs found
Supersymmetry: The Final Countdown
There is hope that the Large Hadron Collider (LHC) at CERN will tell us about
the fate of supersymmetry at the TeVscale. Therefore we might try to identify
our expectations for the discovery of SUSY, especially in the first years of
operation of this machine. In this talk we shall concentrate on the simplest
SUSY scheme: the MSSM with SUSY broken in a hidden sector mediated by
interactions of gravitational strength (gravity-, modulus and
mirage-mediation). Such a situation might be favoured in a large class of
string inspired models. There is a good chance to identify such simple schemes
by knowing the properties of the gaugino mass spectrum such as the
gluino/neutralino mass ratios.Comment: Opening talk at the conference SUSY08, 9 pages, 4 figure
Competitive Positioning in International Logistics: Identifying a System of Attributes Through Neural Networks and Decision Trees
Firms involved in international logistics must develop a system of service attributes that give them a way to be profitable and to satisfy customers’ needs at the same time. How customers trade-off these various attributes in forming satisfaction with competing international logistics providers has not been explored well in the literature. This study explores the ocean freight shipping sector to identify the system of attributes that maximizes customers’ satisfaction. Data were collected from shipping managers in Singapore using personal interviews to identify the chief concerns in choosing and evaluating ocean freight services. The data were then examined using neural networks and decision trees, among other approaches to identify the system of attributes that is connected with customer satisfaction. The results illustrate the power of these methods in understanding how industrial customers with global operations process attributes to derive satisfaction. Implications are discussed
Predicting the dissolution kinetics of silicate glasses using machine learning
Predicting the dissolution rates of silicate glasses in aqueous conditions is
a complex task as the underlying mechanism(s) remain poorly understood and the
dissolution kinetics can depend on a large number of intrinsic and extrinsic
factors. Here, we assess the potential of data-driven models based on machine
learning to predict the dissolution rates of various aluminosilicate glasses
exposed to a wide range of solution pH values, from acidic to caustic
conditions. Four classes of machine learning methods are investigated, namely,
linear regression, support vector machine regression, random forest, and
artificial neural network. We observe that, although linear methods all fail to
describe the dissolution kinetics, the artificial neural network approach
offers excellent predictions, thanks to its inherent ability to handle
non-linear data. Overall, we suggest that a more extensive use of machine
learning approaches could significantly accelerate the design of novel glasses
with tailored properties
N=1 supersymmetric SU(4)xSU(2)LxSU(2)R effective theory from the weakly coupled heterotic superstring
In the context of the free-fermionic formulation of the heterotic
superstring, we construct a three generation N=1 supersymmetric
SU(4)xSU(2)LxSU(2)R model supplemented by an SU(8) hidden gauge symmetry and
five Abelian factors. The symmetry breaking to the standard model is achieved
using vacuum expectation values of a Higgs pair in (4bar,2R)+(4,2R) at a high
scale. One linear combination of the Abelian symmetries is anomalous and is
broken by vacuum expectation values of singlet fields along the flat directions
of the superpotential. All consistent string vacua of the model are completely
classified by solving the corresponding system of F- and D-flatness equations
including non-renormalizable terms up to sixth order. The requirement of
existence of electroweak massless doublets further restricts the
phenomenologically viable vacua. The third generation fermions receive masses
from the tree-level superpotential. Further, a complete calculation of all
non-renormalizable fermion mass terms up to fifth order shows that in certain
string vacua the hierarchy of the fermion families is naturally obtained in the
model as the second and third generation fermions earn their mass from fourth
and fifth order terms. Along certain flat directions it is shown that the ratio
of the SU(4) breaking scale and the reduced Planck mass is equal to the up
quark ratio m_c/m_t at the string scale. An additional prediction of the model,
is the existence of a U(1) symmetry carried by the fields of the hidden sector,
ensuring thus the stability of the lightest hidden state. It is proposed that
the hidden states may account for the invisible matter of the universe.Comment: Latex2e file, 50 pages, uses rotating.st
Proposing a hybrid approach for emotion classification using audio and video data
Emotion recognition has been a research topic in the field of Human-Computer Interaction (HCI) during recent years. Computers have become an inseparable part of human life. Users need human-like interaction to better communicate with computers. Many researchers have
become interested in emotion recognition and classification using different sources. A hybrid
approach of audio and text has been recently introduced. All such approaches have been done to raise the accuracy and appropriateness of emotion classification. In this study, a hybrid approach of audio and video has been applied for emotion recognition. The innovation of this
approach is selecting the characteristics of audio and video and their features as a unique specification for classification. In this research, the SVM method has been used for classifying the data in the SAVEE database. The experimental results show the maximum classification
accuracy for audio data is 91.63% while by applying the hybrid approach the accuracy achieved is 99.26%
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