Combining Non-orthogonal Transmission with Network-Coded Cooperation: Performance Analysis over Nakagami-m Fading Channels

This is the author accepted manuscript. The final version is available from IEEE via the DOI in this recordThis paper investigates efficient transmission design in a class of multi-user cooperation networks, in which multiple information sources intend to distribute their messages to a sufficient proportion of ambient destinations with the assistance of multiple relays. We apply a relaying scheme that combines non-orthogonal transmission with network coding techniques to balance channel consumption and inter-user interference. The sources and relays are divided into clusters, terminals within each of which are allowed to non-orthogonally access the same channel. A class of finite-field network codes are adopted in the relays. We provide the methods to derive the system transmission error probability and diversity-multiplexing tradeoff (DMT), over Nakagami-m fading channels. Through error probability and finite-SNR DMT analysis for certain clustering strategies, and infinite-SNR DMT analysis for general situations, we show that the considered relaying scheme can notably improve system performance over the conventional approach that demands only orthogonal transmission in network-coded cooperation networks.National Natural Science Foundation of ChinaNational Key R&D Program of ChinaEuropean Union Horizon 202

Fire responses and resistance of concrete-filled steel tubular frame structures

This paper presents the results of dynamic responses and fire resistance of concretefilled steel tubular (CFST) frame structures in fire conditions by using non-linear finite element method. Both strength and stability criteria are considered in the collapse analysis. The frame structures are constructed with circular CFST columns and steel beams of I-sections. In order to validate the finite element solutions, the numerical results are compared with those from a fire resistance test on CFST columns. The finite element model is then adopted to simulate the behaviour of frame structures in fire. The structural responses of the frames, including critical temperature and fire-resisting limit time, are obtained for the ISO-834 standard fire. Parametric studies are carried out to show their influence on the load capacity of the frame structures in fire. Suggestions and recommendations are presented for possible adoption in future construction and design of these structures

Production of htt_bar and htT_bar in littlest Higgs model with T-parity

In the littlest Higgs model with T-parity, which predicts a pair of T-even and T-odd partners for the top quark, the top quark interactions are altered with respect to the Standard Model predictions and deviation will manifest in various top quark processes. In this work we examine the effects in htt_bar productions at the ILC and LHC. We find that in the allowed parameter space, the cross sections can be significantly deviated from the Standard Model predictions and thus provide a good test for the littlest Higgs model with T-parity. We also examine the new production channel, the htT_bar or hTt_bar production, at the LHC, which give the same final states as htt_bar production due to the dominant decay T->Wb. We find that, compared with htt_bar production, this new production channel can have a sizable production rate for a T-quark below TeV scale. Such a production will be counted into htt_bar events or possibly extracted from htt_bar events, depending on if we can distinguish the T-quark from the top quark from mass reconstructions.Comment: version in PRD (11 pages, 6 figs

Accurate range-free localization for anisotropic wireless sensor networks

Journal ArticlePosition information plays a pivotal role in wireless sensor network (WSN) applications and protocol/ algorithm design. In recent years, range-free localization algorithms have drawn much research attention due to their low cost and applicability to large-scale WSNs. However, the application of range-free localization algorithms is restricted because of their dramatic accuracy degradation in practical anisotropic WSNs, which is mainly caused by large error of distance estimation. Distance estimation in the existing range-free algorithms usually relies on a unified per hop length (PHL) metric between nodes. But the PHL between different nodes might be greatly different in anisotropic WSNs, resulting in large error in distance estimation. We find that, although the PHL between different nodes might be greatly different, it exhibits significant locality; that is, nearby nodes share a similar PHL to anchors that know their positions in advance. Based on the locality of the PHL, a novel distance estimation approach is proposed in this article. Theoretical analyses show that the error of distance estimation in the proposed approach is only one-fourth of that in the state-of-the-art pattern-driven scheme (PDS). An anchor selection algorithm is also devised to further improve localization accuracy by mitigating the negative effects from the anchors that are poorly distributed in geometry. By combining the locality-based distance estimation and the anchor selection, a range-free localization algorithm named Selective Multilateration (SM) is proposed. Simulation results demonstrate that SM achieves localization accuracy higher than 0.3r, where r is the communication radius of nodes. Compared to the state-of-the-art solution, SM improves the distance estimation accuracy by up to 57% and improves localization accuracy by up to 52% consequently.This work is partially supported by the National Science Foundation of China (61103203, 61173169, 61332004, and 61420106009), the Hong Kong RGC General Research Fund (PolyU 5106/11E), the International Science & Technology Cooperation Program of China (2013DFB10070), and the EU FP7 QUICK project (PIRSES-GA-2013-612652)

The Tensor Current Divergence Equation in U(1) Gauge Theories is Free of Anomalies

The possible anomaly of the tensor current divergence equation in U(1) gauge theories is calculated by means of perturbative method. It is found that the tensor current divergence equation is free of anomalies.Comment: Revtex4, 7 pages, 2 figure

Spin and orbital angular momentum in gauge theories (II): QCD and nucleon spin structure

Parallel to the construction of gauge invariant spin and orbital angular momentum for QED in paper (I) of this series, we present here an analogous but non-trivial solution for QCD. Explicitly gauge invariant spin and orbital angular momentum operators of quarks and gluons are obtained. This was previously thought to be an impossible task, and opens a more promising avenue towards the understanding of the nucleon spin structure.Comment: 3 pages, no figure; presented by F. Wang at NSTAR200

Monodispersed Bioactive Glass Nanoclusters with Ultralarge Pores and Intrinsic Exceptionally High miRNA Loading for Efficiently Enhancing Bone Regeneration

Bioactive glass nanoparticles (BGNs) have attracted much attention in drug delivery and bone tissue regeneration, due to the advantages including biodegradation, high bone‐bonding bioactivity, and facile large‐scale fabrication. However, the wide biomedical applications of BGNs such as efficient gene delivery are limited due to their poor pore structure and easy aggregation. Herein, for the first time, this study reports novel monodispersed bioactive glass nanoclusters (BGNCs) with ultralarge mesopores (10–30 nm) and excellent miRNA delivery for accelerating critical‐sized bone regeneration. BGNCs with different size (100–500 nm) are fabricated by using a branched polyethylenimine as the structure director and catalyst. BGNCs show an excellent apatite‐forming ability and high biocompatibility. Importantly, BGNCs demonstrate an almost 19 times higher miRNA loading than those of conventional BGNs. Additionally, BGNCs–miRNA nanocomplexes exhibit a significantly high antienzymolysis, enhance cellular uptake and miRNA transfection efficiency, overpassing BGNs and commercial Lipofectamine 3000. BGNCs‐mediated miRNA delivery significantly improves the osteogenic differentiation of bone marrow stromal stem cells in vitro and efficiently enhances bone formation in vivo. BGNCs can be a highly efficient nonviral vector for various gene therapy applications. The study may provide a novel strategy to develop highly gene‐activated bioactive nanomaterials for simultaneous tissue regeneration and disease therapy.Monodispersed bioactive glass nanoclusters (BGNCs) with ultra‐large mesopores (10–30 nm) are developed for miRNA delivery to enhance bone regeneration. BGNCs demonstrated an ultrahigh miRNA loading and transfection efficiency, overpassing commercial lipofectamine. BGNCs‐mediated miRNA delivery significantly improved osteogenic differentiation of bone marrow stromal stem cells in vitro and enhanced bone formation in vivo.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/139128/1/adhm201700630-sup-0001-S1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139128/2/adhm201700630.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139128/3/adhm201700630_am.pd

Art of spin decomposition

We analyze the problem of spin decomposition for an interacting system from a natural perspective of constructing angular momentum eigenstates. We split, from the total angular momentum operator, a proper part which can be separately conserved for a stationary state. This part commutes with the total Hamiltonian and thus specifies the quantum angular momentum. We first show how this can be done in a gauge-dependent way, by seeking a specific gauge in which part of the total angular momentum operator vanishes identically. We then construct a gauge-invariant operator with the desired property. Our analysis clarifies what is the most pertinent choice among the various proposals for decomposing the nucleon spin. A similar analysis is performed for extracting a proper part from the total Hamiltonian to construct energy eigenstates.Comment: 5 pages, no figure; published in Phys.Rev.D (Rapid Communications

Modified yupingfeng formula for the treatment of stable chronic obstructive pulmonary disease: a systematic review of randomized controlled trials

Background: Chronic obstructive pulmonary disease (COPD), is a very  common disease of respiratory system. An increasing number of clinical  trials on Yupingfeng formula in the management of stable COPD have been performed. However, the evidence base for it remains unknown. This review aims at assessing the efficacy, and safety of modified Yupingfeng  formula in the treatment of stable COPD through a systematic review of all available randomized controlled trials. Materials and Methods: Literature retrieval was conducted using four English databases (CENTRAL, PubMed, EMBASE, and ISI Web of Science), and four Chinese databases (CBM, CNKI, VIP, and WANFANG), from respective inception to January 2013, and supplemented with a manual search. Review authors independently extracted the trial data, and assessed the quality of each trial. Methodological quality was assessed by Cochrane risk of bias and Jadad’s scale. The following outcomes were evaluated: (1) lung function; (2) 6-minute walk distance (6MWD); (3) effective rate; (4) serum levels of IgA, IgG and IgE; and (5) adverse events. Data were analyzed using STATA 12.0 software.Results: A total of nine studies involving 660, stable COPD patients were identified. Patients from all studies included in this review were randomized to receive Yupingfeng formula combined with Western medications in comparison with Western medications. In general, the methodological quality of the included trials was poor. The results of this systematic review indicates that, compared with Western medications alone, the use of Yupingfeng formula, if combined with Western medications could significantly improve FEV1 (WMD = 0.30L; 95%CI: 0.19, 0.42), FEV1/FVC ratio (SMD = 0.69; 95%CI: 0.48, 0.91), 6MWD (WMD = 31.73m; 95% CI: 19.29, 44.17), and effective rate (RR = 1.24; 95% CI: 1.10, 1.41), and increase the serum levels of IgA (WMD = 0.25; 95%CI: 0.16, 0.34) and IgG (WMD = 1.10; 95%CI: 0.53, 1.68), but no difference was found in the serum IgE levels (WMD = 0.47; 95%CI: －0.32, 1.27) between the two groups. No serious adverse events were reported.Conclusions: Within the limitations of this systematic review, we may conclude that compared with Western medications alone, Yupingfeng formula, when combined with Western medications can provide more benefits for patients with stable COPD, without any serious adverse reactions being identified. However, these benefits need to be further confirmed through high-quality prospective placebo-controlled trials that should be strictly conducted in accordance with methodological principles and procedures.Key words: Yupingfeng formula; chronic obstructive pulmonary disease; Systematic revie

Social Computing for Mobile Big Data

Mobile big data contains vast statistical features in various dimensions, including spatial, temporal, and the underlying social domain. Understanding and exploiting the features of mobile data from a social network perspective will be extremely beneficial to wireless networks, from planning, operation, and maintenance to optimization and marketing