4,149 research outputs found
Flavor Changing Neutral Currents in the Asymmetric Left-Right Gauge Model
In the
extension of the standard model, a minimal (but asymmetric) scalar sector
consists of one doublet and one bidoublet.
Previous and recent studies have shown that this choice is useful for
understanding neutrino mass as well as dark matter. The constraints from flavor
changing neutral currents mediated by the scalar sector are discussed in the
context of the latest experimental data
Multilepton Higgs Decays through the Dark Portal
The U(1)_D gauge sector containing one dark Higgs boson h_D and one dark
photon \gamma_D may be explored through the decays of the 126 GeV particle
discovered at the Large Hadron Collider (LHC), assumed here as the heavier mass
eigenstate h_1 in the mixing of the standard model h with h_D. The various
decays of h_1 to \gamma_D \gamma_D, h_2 h_2, h_2 \gamma_D \gamma_D and h_2 h_2
h_2 would yield multilepton final states through the mixing of \gamma_D with
the photon and the decay h_2 \to \gamma_D \gamma_D, where h_2 is the lighter
dark Higgs. Future searches for signals of multilepton jets at the LHC may
reveal the existence of this possible dark sector governed simply by the
original Abelian Higgs model.Comment: 20 pages, 9 figures, 2 tables. New section added for signals of
multilepton jets at the LHC-1
Designing Learning Analytics for Effective Learning Through Problem-Based Learning
This paper describes the development of a learning analytic course for a post-graduate programme at the authors’ university for adult learning. The analytics course is very timely, given the proliferation of Big Data and the need for industries to embrace analytics to examine and solve a range of business problems using data analytics. This is an educational pedagogy and practice paper to design and develop Learning Analytics using Problem-Based Learning (PBL). The contribution of this paper is to help educators in the community who are keen to design and develop similar courses to have a better understanding of data generation, assessment writing, team formation, and challenges faced. The paper will examine and describe the use of the PBL approach to teach learning analytics. The PBL is adopted as it demonstrates a learning design that integrates industry experience with practice-based learning within the classroom. As an approach, it equips students with the ability to solve complex problems through context-driven inquiries. The course has been well-received by students and this paper will discuss the strengths of this approach. Keywords: course planning and development, learning analytics, problem-based learning, course delivery, assessment development DOI: 10.7176/JEP/11-18-03 Publication date:June 30th 202
Identifiability of the Simplex Volume Minimization Criterion for Blind Hyperspectral Unmixing: The No Pure-Pixel Case
In blind hyperspectral unmixing (HU), the pure-pixel assumption is well-known
to be powerful in enabling simple and effective blind HU solutions. However,
the pure-pixel assumption is not always satisfied in an exact sense, especially
for scenarios where pixels are heavily mixed. In the no pure-pixel case, a good
blind HU approach to consider is the minimum volume enclosing simplex (MVES).
Empirical experience has suggested that MVES algorithms can perform well
without pure pixels, although it was not totally clear why this is true from a
theoretical viewpoint. This paper aims to address the latter issue. We develop
an analysis framework wherein the perfect endmember identifiability of MVES is
studied under the noiseless case. We prove that MVES is indeed robust against
lack of pure pixels, as long as the pixels do not get too heavily mixed and too
asymmetrically spread. The theoretical results are verified by numerical
simulations
Quantum Criticality from in-situ Density Imaging
We perform large-scale Quantum Monte Carlo (QMC) simulations for strongly
interacting bosons in a 2D optical lattice trap, and confirm an excellent
agreement with the benchmarking in-situ density measurements by the Chicago
group [1]. We further present a general finite temperature phase diagram both
for the uniform and the trapped systems, and demonstrate how the universal
scaling properties near the superfluid(SF)-to-Mott insulator(MI) transition can
be observed by analysing the in-situ density profile. The characteristic
temperature to find such quantum criticality is estimated to be of the order of
the single-particle bandwidth, which should be achievable in the present or
near future experiments. Finally, we examine the validity regime of the local
fluctuation-dissipation theorem (FDT), which can be a used as a thermometry in
the strongly interacting regime.Comment: 4 page
Genetic marking and characterization of Tac2-expressing neurons in the central and peripheral nervous system
Background: The neurocircuits that process somatic sensory information in the dorsal horn of the spinal cord are still poorly understood, with one reason being the lack of Cre lines for genetically marking or manipulating selective subpopulations of dorsal horn neurons. Here we describe Tac2-Cre mice that were generated to express the Cre recombinase gene from the Tac2 locus. Tachykinin 2 (Tac2) encodes a neurotransmitter, neurokinin B (NKB). Results: By crossing Tac2-Cre mice with ROSA26-tdTomato reporter mice, we directly visualized Tac2 lineage neurons in the dorsal root ganglia, the dorsal horn of the spinal cord, and many parts of the brain including the olfactory bulb, cerebral cortex, amygdala, hippocampus, habenula, hypothalamus, and cerebellum. This Tac2-Cre allele itself was a null allele for the Tac2 gene. Behavioral analyses showed that Tac2 homozygous null mice responded normally to a series of algogenic (pain-inducing) and pruritic (itch-inducing) stimuli. Conclusions: Tac2-Cre mice are a useful tool to mark specific subsets of neurons in the sensory ganglia, the dorsal spinal cord, and the brain. These mice can also be used for future genetic manipulations to study the functions of Tac2-expressing neurons or the functions of genes expressed in these neurons
The multiple originator broadcasting problem in graphs
AbstractGiven a graph G and a vertex subset S of V(G), the broadcasting time with respect to S, denoted by b(G,S), is the minimum broadcasting time when using S as the broadcasting set. And the k-broadcasting number, denoted by bk(G), is defined by bk(G)=min{b(G,S)|S⊆V(G),|S|=k}.Given a graph G and two vertex subsets S, S′ of V(G), define d(v,S)=minu∈Sd(v,u), d(S,S′)=min{d(u,v)|u∈S, v∈S′}, and d(G,S)=maxv∈V(G)d(v,S) for all v∈V(G). For all k, 1⩽k⩽|V(G)|, the k-radius of G, denoted by rk(G), is defined as rk(G)=min{d(G,S)|S⊆V(G), |S|=k}.In this paper, we study the relation between the k-radius and the k-broadcasting numbers of graphs. We also give the 2-radius and the 2-broadcasting numbers of the grid graphs, and the k-broadcasting numbers of the complete n-partite graphs and the hypercubes
Multi-Hop Routing Mechanism for Reliable Sensor Computing
Current research on routing in wireless sensor computing concentrates on increasing the service lifetime, enabling scalability for large number of sensors and supporting fault tolerance for battery exhaustion and broken nodes. A sensor node is naturally exposed to various sources of unreliable communication channels and node failures. Sensor nodes have many failure modes, and each failure degrades the network performance. This work develops a novel mechanism, called Reliable Routing Mechanism (RRM), based on a hybrid cluster-based routing protocol to specify the best reliable routing path for sensor computing. Table-driven intra-cluster routing and on-demand inter-cluster routing are combined by changing the relationship between clusters for sensor computing. Applying a reliable routing mechanism in sensor computing can improve routing reliability, maintain low packet loss, minimize management overhead and save energy consumption. Simulation results indicate that the reliability of the proposed RRM mechanism is around 25% higher than that of the Dynamic Source Routing (DSR) and ad hoc On-demand Distance Vector routing (AODV) mechanisms
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