74,924 research outputs found
KN and KbarN Elastic Scattering in the Quark Potential Model
The KN and KbarN low-energy elastic scattering is consistently studied in the
framework of the QCD-inspired quark potential model. The model is composed of
the t-channel one-gluon exchange potential, the s-channel one-gluon exchange
potential and the harmonic oscillator confinement potential. By means of the
resonating group method, nonlocal effective interaction potentials for the KN
and KbarN systems are derived and used to calculate the KN and KbarN elastic
scattering phase shifts. By considering the effect of QCD renormalization, the
contribution of the color octet of the clusters (qqbar) and (qqq) and the
suppression of the spin-orbital coupling, the numerical results are in fairly
good agreement with the experimental data.Comment: 20 pages, 8 figure
Recommended from our members
Evolutionary optimization within an intelligent hybrid system for design integration
An intelligent hybrid approach has been developed to integrate various stages in total design, including formulation of product design specifications, conceptual design, detail design, and manufacture. The integration is achieved by blending multiple artificial intelligence (AI) techniques and CAD/CAE/CAM into a single environment. It has been applied into power transmission system design. In addition to knowledge-based systems and artificial neural networks, another AI technique, genetic algorithms (GAs), are involved in the approach. The GA is used to conduct optimization tasks: (1) searching the best combination of design parameters to obtain optimum design of gears, and (2) optimization of the architecture of the artificial neural networks used in the hybrid system. In this paper, after a brief overview of the intelligent hybrid system, the GA applications are described in detail
The definition of "Insider" in section 3 of the securities markets Act 1988: A review and comparison with other jurisdictions
Statutory definitions of what constitutes an “insider” for the purposes of insider trading laws may
be based on either a “person connection” approach or an “information connection” approach.
The “person connection” approach defines “insider” by reference to the relationship of the
person to the public issuer of securities, while the “information connection” approach considers
anyone who has material price-sensitive information about the issuer to be an insider,
regardless of his or her relationship to the issuer.
In common with Japan, Hong Kong and China, New Zealand’s insider trading law — the
Securities Markets Act 1988 — uses a person connection approach in its definition of “insider”.
Other jurisdictions, however, including both the United Kingdom and Australia, have, to varying
degrees, recently amended their definitions to reflect the information connection approach. The
United States, although the first country to address the issue of insider trading, lacks a statutory
definition of “insider” and instead relies on generally applicable laws against securities fraud. It
has developed a definition with elements of both approaches.
This paper reviews the definitions in use in the United States and in other countries (including
New Zealand) which have been influenced by the American experience. It concludes that the
narrow, relationship-based approach does not capture some conduct that may be damaging to
the integrity of the securities market. A definition based on the information connection approach
(perhaps combined with elements of the person connection approach) may therefore be
preferable to New Zealand’s current definition
Recommended from our members
SREBP1-dependent de novo fatty acid synthesis gene expression is elevated in malignant melanoma and represents a cellular survival trait.
de novo fatty acid biosynthesis (DNFA) is a hallmark adaptation of many cancers that supports survival, proliferation, and metastasis. Here we elucidate previously unexplored aspects of transcription regulation and clinical relevance of DNFA in cancers. We show that elevated expression of DNFA genes is characteristic of many tumor types and correlates with poor prognosis, especially in melanomas. Elevated DNFA gene expression depends on the SREBP1 transcription factor in multiple melanoma cell lines. SREBP1 predominantly binds to the transcription start sites of DNFA genes, regulating their expression by recruiting RNA polymerase II to promoters for productive transcription elongation. We find that SREBP1-regulated DNFA represents a survival trait in melanoma cells, regardless of proliferative state and oncogenic mutation status. Indeed, malignant melanoma cells exhibit elevated DNFA gene expression after the BRAF/MEK signaling pathway is blocked (e.g. by BRAF inhibitors), and DNFA expression remains higher in melanoma cells resistant to vemurafenib treatment than in untreated cells. Accordingly, DNFA pathway inhibition, whether by direct targeting of SREBP1 with antisense oligonucleotides, or through combinatorial effects of multiple DNFA enzyme inhibitors, exerts potent cytotoxic effects on both BRAFi-sensitive and -resistant melanoma cells. Altogether, these results implicate SREBP1 and DNFA enzymes as enticing therapeutic targets in melanomas
Dark Matter in the Left Right Twin Higgs Model
In the left-right twin Higgs model, one of the neutral Higgses is a natural
candidate for WIMP dark matter. We analyzed the dark matter relic density in
this framework and identified regions of parameter space that provide the right
amount of dark matter. We also studied the dark matter in the more general
inert Higgs doublet model in which the mass splittings between the dark matter
and other particles do not follow the relations in the left-right twin Higgs
model.Comment: 18 page
A data collection scheme for identification of parameters in a driver model
A high gain steering controller to compensate for limitations in a handicapped driver's range of motion is employed when adapting vehicle to his use. A driver/vehicle system can become unstable as vehicle speed is increased, therefore it is desirable to use a computer simulation of the driver/vehicle combination as a design tool to investigate the system response prior to construction of a controller and road testing. Unknown driver parameters must be identified prior to use of the model for system analysis. A means to collect the data necessary for identification of these driver model parameters without extensive instrumentation of a vehicle to measure and record vehicle states is addressed. Initial tests of the procedure identified all of the driver parameters with errors of 6% or less
- …