1,330 research outputs found
Power system fuzzy bang-bang stabilizer design VIA critical path method
[[abstract]]This paper addresses a new approach, called the optimal path estimation method (OPEM), to implement the time optimal bang-bang control. The method is based on feedback information obtained by estimating the distance from the present state to the switching surface along the optimal trajectory. A fuzzy algorithm is used for the implementation of the control logic. Advantages of the proposed method over traditional bang-bang control method are illustrated by numerical simulations of a multimachine infinite-bus power system[[conferencetype]]國際[[conferencedate]]19950522~19950527[[conferencelocation]]Taipei, Taiwa
Controlling Entanglement Dynamics by Choosing Appropriate Ratio between Cavity-Fiber Coupling and Atom-Cavity Coupling
The entanglement characteristics including the so-called sudden death effect
between two identical two-level atoms trapped in two separate cavities
connected by an optical fiber are studied. The results show that the time
evolution of entanglement is sensitive not only to the degree of entanglement
of the initial state but also to the ratio between cavity-fiber coupling () and
atom-cavity coupling (). This means that the entanglement dynamics can be
controlled by choosing specific v and g.Comment: 14pages, 3figures, conferenc
Probing MSSM Higgs Sector with Explicit CP Violation at a Photon Linear Collider
The CP properties of Higgs bosons can be probed through their s-channel
resonance productions via photon-photon collisions by use of circularly and/or
linearly polarized backscattered laser photons at a TeV-scale linear e^+ e^-
collider. Exploiting this powerful tool, we investigate in detail the Higgs
sector of the minimal supersymmetric Standard Model with explicit CP violation.Comment: 18 pages, 5 figures. Some comments added and typos corrected. To
appear in Phys. Rev.
Tau-Sleptons and Tau-Sneutrino in the MSSM with Complex Parameters
We present a phenomenological study of tau-sleptons stau_1,2 and
tau-sneutrino in the Minimal Supersymmetric Standard Model with complex
parameters A_tau, mu and M_1. We analyse production and decays of stau_1,2 and
tau-sneutrino at a future e^+ e^- collider. We present numerical predictions
for the important decay rates, paying particular attention to their dependence
on the complex parameters. The branching ratios of the fermionic decays of
stau_1 and tau-sneutrino show a significant phase dependence for tan(beta) <
10. For tan(beta) > 10 the branching ratios for the stau_2 decays into Higgs
bosons depend very sensitively on the phases. We show how information on the
phase phi(A_tau) and the other fundamental stau parameters can be obtained from
measurements of the stau masses, polarized cross sections and bosonic and
fermionic decay branching ratios, for small and large tan(beta) values. We
estimate the expected errors for these parameters. Given favorable conditions,
the error of A_tau is about 10% to 20%, while the errors of the remaining stau
parameters are in the range of approximately 1% to 3%. We also show that the
induced electric dipole moment of the tau-lepton is well below the current
experimental limit.Comment: LaTex, 25 pages, 11 figures (included); v2: extended discussion on
error determination, version to appear in Phys.Rev.
Acid-sensing ion channels (ASICs) as pharmacological targets for neurodegenerative diseases
A significant drop of tissue pH or acidosis is a common feature of acute neurological conditions such as ischemic stroke, brain trauma, and epileptic seizures. Acid-sensing ion channels, or ASICs, are proton-gated cation channels widely expressed in peripheral sensory neurons and in the neurons of the central nervous system. Recent studies have demonstrated that activation of these channels by protons plays an important role in a variety of physiological and pathological processes such as nociception, mechanosensation, synaptic plasticity, and acidosis-mediated neuronal injury. This review provides an overview of the recent advance in electrophysiological, pharmacological characterization of ASICs, and their role in neurological diseases. Therapeutic potential of current available ASIC inhibitors is discussed
CP--violating Chargino Contributions to the Higgs Coupling to Photon Pairs in the Decoupling Regime of Higgs Sector
In most supersymmetric theories, charginos belong to
the class of the lightest supersymmetric particles and the couplings of Higgs
bosons to charginos are in general complex so that the CP--violating chargino
contributions to the loop--induced coupling of the lightest Higgs boson to
photon pairs can be sizable even in the decoupling limit of large pseudoscalar
mass with only the lightest Higgs boson kinematically accessible at
future high energy colliders. We introduce a specific benchmark scenario of CP
violation consistent with the electric dipole moment constraints and with a
commonly accepted baryogenesis mechanism in the minimal supersymmetric Standard
Model. Based on the benchmark scenario of CP violation, we demonstrate that the
fusion of the lightest Higgs boson in linearly polarized photon--photon
collisions can allow us to confirm the existence of the CP--violating chargino
contributions {\it even in the decoupling regime of the Higgs sector} for
nearly degenerate SU(2) gaugino and higgsino mass parameters of about the
electroweak scale.Comment: 1+13 pages, 3 eps figure
CP asymmetry in the Higgs decay into the top pair due to the stop mixing
We investigate a potentially large CP violating asymmetry in the decay of a
neutral scalar or pseudoscalar Higgs boson into the top-anti-top pair. The
source of the CP nonconservation is the complex mixing in the (left-right) stop
sector. One of the interesting consequence is the different rates of the Higgs
boson decays into CP conjugate polarized states.Comment: 14 pages, 8 figures include
Probing the MSSM Higgs Boson Sector with Explicit CP Violation through Third Generation Fermion Pair Production at Muon Colliders
We perform a systematic study of the production of a third-generation
fermion-pair, for , and t in the minimal
supersymmetric standard model (MSSM) with explicit CP violation, which is
induced radiatively by soft trilinear interactions related to squarks of the
third generation. We classify all the observables for probing the CP property
of the Higgs bosons constructed by the initial muon beam polarization along
with the unpolarized final fermions and with the final-fermion polarization
configuration of equal helicity, respectively. The observables allow for
complete determination of CP property of the neutral Higgs bosons. The
interference between the Higgs boson and gauge boson contributions also could
provide a powerful method for the determination of the CP property of two heavy
Higgs bosons in the top-quark pair production near the energy region of the
Higgs-boson resonances. For the lightest Higgs-boson mass there is no sizable
interference between scalar and vector contributions for the determination of
the CP property of the lightest Higgs boson. We give a detailed numerical
analysis to show how the radiatively-induced CP violation in the Higgs sector
of the MSSM can be measured.Comment: 30 pages, 7 figures including 5 eps ones. Typos corrected and
references added. To appear in Phys. Rev.
s-Channel Production of MSSM Higgs Bosons at a Muon Collider with Explicit CP Violation
A muon collider with controllable energy resolution and transverse beam
polarization provides a powerful probe of the Higgs sector in the minimal
supersymmetric standard model with explicit CP violation, through s-channel
production of Higgs bosons. The production rates and the CP-even and CP-odd
transverse-polarization asymmetries are complementary in diagnosing CP
violation in the Higgs sector.Comment: 12 pages, 5 figures. Some statements for clarity and references
added. To appear in Phys. Rev.
Prognostic significance of nm23-H1 expression in oral squamous cell carcinoma
Recent studies indicated nm23-H1 played a role in cancer progression. Therefore, we investigated clinical significance of nm23-H1 expression in oral squamous cell carcinoma (OSCC). In total, 86 OSCC specimens were immunohistochemically stained with nm23-H1-specific monoclonal antibodies. Immunohistochemical staining of nm23-H1 was confirmed by immunoblotting. The relations between nm23-H1 expression and clinicopathologic variables were evaluated by chi(2) analysis. As increased size of primary tumour could escalate metastatic potential and the data of patients at the late T stage might confound statistical analyses, we thus paid special attention to 54 patients at the early T stage of OSCC. Statistical difference of survival was compared by a log-rank test. Immunohistochemically, nm23-H1 expression was detected in 48.8% (42 out of 86) of tumorous specimens. It positively correlated with larger primary tumour size (P = 0.03) and inversely with cigarette-smoking habit (P = 0.042). In patients at the early T stage, decreased nm23 expression was associated with increased incidence of lymph node metastasis (P = 0.004) and indicated poor survival (P = 0.014). Tumour nm23-H1 expression is a prognostic factor for predicting better survival in OSCC patients at the early T stage, which may reflect antimetastatic potential of nm23. Therefore, modulation of nm23-H1 expression in cancer cells can provide a novel possibility of improving therapeutic strategy at this stage. In addition, our results further indicated cigarette smoking could aggravate the extent of nm23-H1 expression and possibly disease progression of OSCC patients. (C) 2004 Cancer Research UK
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