48,442 research outputs found
Orbital elements of barium stars formed through a wind accretion scenario
Taking the total angular momentum conservation in place of the tangential
momentum conservation, and considering the square and higher power terms of
orbital eccentricity e, the changes of orbital elements of binaries are
calculated for wind accretion scenario. These new equations are used to
quantitatively explain the observed (e,logP) properties of normal G, K giants
and barium stars. Our results reflect the evolution from G, K giant binaries to
barium binaries, moreover, the barium stars with longer orbital periods P>1600
days may be formed by accreting part of the ejecta from the intrinsic AGB stars
through wind accretion scenario.Comment: 7 pages, LaTex, 4 PS figures and 1 table included, accepted for
publication in A &
Fronthaul-Constrained Cloud Radio Access Networks: Insights and Challenges
As a promising paradigm for fifth generation (5G) wireless communication
systems, cloud radio access networks (C-RANs) have been shown to reduce both
capital and operating expenditures, as well as to provide high spectral
efficiency (SE) and energy efficiency (EE). The fronthaul in such networks,
defined as the transmission link between a baseband unit (BBU) and a remote
radio head (RRH), requires high capacity, but is often constrained. This
article comprehensively surveys recent advances in fronthaul-constrained
C-RANs, including system architectures and key techniques. In particular, key
techniques for alleviating the impact of constrained fronthaul on SE/EE and
quality of service for users, including compression and quantization,
large-scale coordinated processing and clustering, and resource allocation
optimization, are discussed. Open issues in terms of software-defined
networking, network function virtualization, and partial centralization are
also identified.Comment: 5 Figures, accepted by IEEE Wireless Communications. arXiv admin
note: text overlap with arXiv:1407.3855 by other author
Probing multipartite entanglement in a coupled Jaynes-Cummings system
We show how to probe multipartite entanglement in coupled Jaynes-Cummings
cells where the degrees of freedom are the electronic energies of each of the
atoms in separate single-mode cavities plus the single-mode fields
themselves. Specifically we propose probing the combined system as though it is
a dielectric medium. The spectral properties and transition rates directly
reveal multipartite entanglement signatures. It is found that the Hilbert space
of the cell system can be confined to the totally symmetric subspace of two
states only that are maximally-entangled W states with 2N degrees of freedom
Detection of Minimum-Ionizing Particles and Nuclear Counter Effect with Pure BGO and BSO Crystals with Photodiode Read-out
Long BGO (Bismuth Germanate) and BSO (Bismuth Silicate) crystals coupled with
silicon photodiodes have been used to detect minimum-ionizing particles(MIP).
With a low noise amplifier customized for this purpose, the crystals can detect
MIPs with an excellent signal-to-noise ratio. The NCE(Nuclear Counter Effect}
is also clearly observed and measured. Effect of full and partial wrapping of a
reflector around the crystal on light collection is also studied.Comment: 18 pages, including 5 figures; LaTeX and EP
An improved approximation algorithm for computing disjoint QoS paths
©2006 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.The survivability of a network has assumed great importance in against of losing huge volumes of data due to a link cut or node failure. Recently some scholars have proposed some path restoration schemes which used two disjoint paths with multiple constraints to satisfy both the survivability and the QoS requirements. In this paper we will study the issue of how to identify two paths that satisfy the multiple QoS constraints imposed by network applications. More specifically, we will focus on finding two link-disjoint paths that satisfy the delay constraints at a reasonable total cost. We present two efficient approximation algorithms with provable performance guarantees for this problem.Chao Peng, Hong She
Evaluating service marketing in airline industry and its influence on student passengers' purchasing behaviour-using Taipei-London route as an example.
This paper reports an empirical study into airline consumer purchase behaviour on a major global route, that between the United Kingdom and Taipei. It focuses on the factors influencing airline choice for a sample of 60 Taiwanese students based at UK Universities and travelling on five airlines: British Airways, Cathay Pacific Airways, China Airlines, EVA Airways and Royal Dutch Airways. Several stages of data-gathering were undertaken and a well-established analytical framework for services marketing was used to identify gaps between the desired and received service. The main findings suggest that service quality, including in-flight entertainment, cabin crew attitude and seating comfort, can be as important as, or more important than, price in student purchase decisions for long-haul flights. Other important factors in carrier choice included student discounts, baggage allowances and airline safety record.
Key Words: Service Marketing, Airline Industry, Consumer Behaviour, Taiwan, Touris
Political advertising in democratic Taiwan: audiences' perspectives on political figures through image-building advertisements
One can gain important insights into the effects of political advertising by looking at decoding and interpretation in audience perception studies. This essay considers two genres of political advertisement-celebrity endorsement and emotional appeal-through six focus groups formed by either Democratic Progressive Party (DPP) or Kuomintang (KMT) identifiers. It focuses on three key themes for comparison: the participants’ involvement, their interpretations of the key messages, and opinions that were important to them. This study aims to further the understanding of how political advertisements are interpreted and to bring some practical knowledge to the field by comparing the perspectives of audiences of differing political orientations
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