6,797 research outputs found
Mean Square Capacity of Power Constrained Fading Channels with Causal Encoders and Decoders
This paper is concerned with the mean square stabilization problem of
discrete-time LTI systems over a power constrained fading channel. Different
from existing research works, the channel considered in this paper suffers from
both fading and additive noises. We allow any form of causal channel
encoders/decoders, unlike linear encoders/decoders commonly studied in the
literature. Sufficient conditions and necessary conditions for the mean square
stabilizability are given in terms of channel parameters such as transmission
power and fading and additive noise statistics in relation to the unstable
eigenvalues of the open-loop system matrix. The corresponding mean square
capacity of the power constrained fading channel under causal encoders/decoders
is given. It is proved that this mean square capacity is smaller than the
corresponding Shannon channel capacity. In the end, numerical examples are
presented, which demonstrate that the causal encoders/decoders render less
restrictive stabilizability conditions than those under linear
encoders/decoders studied in the existing works.Comment: Accepted by the 54th IEEE Conference on Decision and Contro
CP violation in neutrino mixing with in Type-II seesaw model
We study a class of models for neutrino mass matrix in Type-II seesaw with
family symmetry. The resulting neutrino mass matrix can be naturally made
to respect a exchange plus CP conjugate symmetry (GLS) with the CP
violating phase and the mixing angle predicted to be
and , respectively. When GLS is explicitly broken by complex
Yukawa couplings, the model predictions for and can be
significantly modified. Should future experiments will indeed determine
and away from the GLS limit values, one then had to
consider models with broken GLS. We study several simple scenarios to show how
the modifications arise when GLS is broken and how future experiments can test
this class of models.Comment: 15 pages, 3 figures, minor errors corrected. Version appeared in
Phys.Lett.B. arXiv admin note: text overlap with arXiv:1504.0156
Predictive Violating Relations for Charmless Two-body Decays of Beauty Baryons and With Flavor Symmetry
Several baryons containing a heavy b-quark have been discovered. The decays
of these states provide new platform for testing the standard model (SM). We
study violation in SM for charmless two-body decays of the flavor
anti-triplet beauty baryon (b-baryon) in a model independent way. We found, in the
flavor symmetry limit, a set of new predictive relations among the
branching ratio and asymmetry for decays, such as
,
,and . Future data from LHCb can test these relations and
also other relations found.Comment: 13 pages, no figure, 6 tables, several missing terms in eq.11 are
adde
Economic Transition and the Motherhood Wage Penalty in Urban China: Investigation using Panel Data
Chinaβs economic transition has fundamentally changed the mechanisms for allocating and compensating labor. This paper investigates how the economic transition has affected the wage gap between mothers and childless women in urban China using panel data for the period 1990-2005. The results show that overall, mothers earned considerably less than childless women; additionally, the wage penalties for motherhood went up substantially from the gradualist reform period (1990-1996) to the radical reform period (1999-2005). The results also show that that although motherhood does not appear to have a significant wage effect for the state sector, it imposes substantial wage losses for mothers in the non-state sector. These findings suggest that the economic transition has shifted part of the cost of child-bearing and -rearing from the state and employers back to women in the form of lower earnings for working mothers.
Some Predictions of Diquark Model for Hidden Charm Pentaquark Discovered at the LHCb
The LHCb has discovered two new states with preferred quantum numbers
and from decays. These new states can be
interpreted as hidden charm pentaquarks. It has been argued that the main
features of these pentaquarks can be described by diquark model. The diquark
model predicts that the and are in two separate octet
multiplets of flavor and there is also an additional decuplet
pentaquark multiplet. Finding the states in these multiplets can provide
crucial evidence for this model. The weak decays of b-baryon to a light meson
and a pentaquark can have Cabibbo allowed and suppressed decay channels. We
find that in the limit, for -spin related decay modes the ratio of
the decay rates of Cabibbo suppressed to Cabibbo allowed decay channels is
given by . There are also other testable relations for
b-baryon weak decays into a pentaquark and a light pseudoscalar. These
relations can be used as tests for the diquark model for pentaquark.Comment: revtex, 19 pages, 3 figures. one reference added and some typos
correcte
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