36,176 research outputs found
Search for single vector-like quark production in hadronic final states at the LHC
No full textIn this paper, we study the discovery potential of a Vector-Like quark (VLB) via the process at the Large Hadron Collider (LHC) with TeV. In the framework of a simplified model, we perform a scan over its parameter space and test its viability following a Monte Carlo analysis developed to include all production and decay dynamics. We use cut-and-count combined with Extreme Gradient Boosting (XGBoost) methods to classify the signal and background events in order to improve the efficiency of signal identification and background rejection. We find that this approach can reduce background events significantly while the signal retention rate is much higher than that of traditional methods, thereby improving the VLB discovery potential. We then calculate the exclusion and discovery capabilities for VLBs and find that the advantages of the cut-and-count plus XGBoost method especially lie in the high-mass region, i.e., m_B > 1500 \text{ GeV}. We finally obtain the following LHC results in terms of the coupling and chiral structure of a singlet heavy VLB interactions: (i) for =0.2 and with 3000 fb, the quark mass can be be excluded (discovered) up to 3000 GeV (2500 GeV); (ii) for =0.2 and with 3000 fb, the exclusion (discovery) region can reach up to 4750 GeV (4250 GeV)
Single production of an exotic vector-like Y quark at future high energy pp colliders
No full textVector-like quarks have been predicted in various new physics scenarios beyond the Standard Model (SM). In a simplified modelling of a (B,Y) doublet including a vector-like quark Y, with charge −43e, there are only two free parameters: the Y coupling κY and mass mY. In the five flavor scheme, we investigate the single production of the Y state decaying into Wb at the Large Hadron Collider (LHC) Run-III and High-Luminosity LHC (HL-LHC) operating at s√ = 14 TeV, the possible High-Energy LHC (HE-LHC) with s√ = 27 TeV as well as the Future Circular Collider in hadron-hadron mode (FCC-hh) with s√ = 100 TeV. Through detailed signal-to-background analyses and detector simulations, we assess the exclusion capabilities of the Y state at the different colliders. We find that this can be improved significantly with increasing collision energy, especially at the HE-LHC and FCC-hh, both demonstrating an obvious advantage with respect to the HL-LHC case in the case of high mY. Assuming a 10% systematic uncertainty on the background event rate, the exclusion capabilities are summarized as follows: (1) the LHC Run-III can exclude the correlated regions of κY∈[0.044,0.5] and mY∈[1000 GeV,3099 GeV] with integrated luminosity L=300 fb−1; (2) the HL-LHC can exclude the correlated regions of κY∈[0.027,0.5] and mY∈[1000 GeV,3653 GeV] with L=3 ab−1; (3) the HE-LHC can exclude the correlated regions of κY∈[0.030,0.5] and mY∈[1000 GeV,4936 GeV] with L=3 ab−1; (4) the FCC-hh can exclude the correlated regions of κY∈[0.051,0.5] and mY∈[1000 GeV,6610 GeV] with L=3 ab−1
Tripletino-like WIMP dark matter in the supersymmetric georgi-Machacek model
No full textThe Supersymmetric Custodial Triplet Model (SCTM), a Supersymmetric generalization of the Georgi-Machacek (GM) model, is constructed by extending the Higgs sector of the Minimal Supersymmetric Standard Model by three triplet chiral Superfields with hypercharge Y=0,\pm 1, in order to maintain the holomorphy of the Superpotential and satisfy the requirements of anomaly cancellation. The global SU(2)_L\otimes SU(2)_R symmetry has to be respected for the Superpotential and soft Supersymmetry breaking sector, where the former will only be broken by the Yukawa couplings and the latter one will be broken spontaneously to the custodial SU(2)_V symmetry after Electro-Weak Symmetry Breaking similar as the GM model. The ensuing complicated spectrum not only gives rich collider phenomenology but also provides more available Weakly Interacting Massive Particle (WIMP) Dark Matter (DM) candidates. In this paper, we explore the viability of WIMP solutions for DM in the SCTM, by considering the increasingly stringent constraints from direct detection DM experiments. Our numerical simulations show that a significant portion of the SCTM parameter space remains viable despite these constraints and will be fully tested in future experiments
Special issue: Process safety in times of a pandemic
No full textGreen Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Safety and Security Scienc
Distributed human computation framework for linked data co-reference resolution
No full textDistributed Human Computation (DHC) is a technique used to solve computational problems by incorporating the collaborative effort of a large number of humans. It is also a solution to AI-complete problems such as natural language processing. The Semantic Web with its root in AI is envisioned to be a decentralised world-wide information space for sharing machine-readable data with minimal integration costs. There are many research problems in the Semantic Web that are considered as AI-complete problems. An example is co-reference resolution, which involves determining whether different URIs refer to the same entity. This is considered to be a significant hurdle to overcome in the realisation of large-scale Semantic Web applications. In this paper, we propose a framework for building a DHC system on top of the Linked Data Cloud to solve various computational problems. To demonstrate the concept, we are focusing on handling the co-reference resolution in the Semantic Web when integrating distributed datasets. The traditional way to solve this problem is to design machine-learning algorithms. However, they are often computationally expensive, error-prone and do not scale. We designed a DHC system named iamResearcher, which solves the scientific publication author identity co-reference problem when integrating distributed bibliographic datasets. In our system, we aggregated 6 million bibliographic data from various publication repositories. Users can sign up to the system to audit and align their own publications, thus solving the co-reference problem in a distributed manner. The aggregated results are published to the Linked Data Cloud
Intersystem soft handover for converged DVB-H and UMTS networks
No full textDigital video broadcasting for handhelds (DVB-H) is the standard for broadcasting Internet Protocol (IP) data services to mobile portable devices. To provide interactive services for DVB-H, the Universal Mobile Telecommunications System (UMTS) can be used as a terrestrial interaction channel for the unidirectional DVB-H network. The converged DVB-H and UMTS network can be used to address the congestion problems due to the limited multimedia channel accesses of the UMTS network. In the converged network, intersystem soft handover between DVB-H and UMTS is needed for an optimum radio resource allocation, which reduces network operation cost while providing the required quality of service. This paper deals with the intersystem soft handover between DVB-H and UMTS in such a converged network. The converged network structure is presented. A novel soft handover scheme is proposed and evaluated. After considering the network operation cost, the performance tradeoff between the network quality of service and the network operation cost for the intersystem soft handover in the converged network is modeled using a stochastic tree and analyzed using a numerical simulation. The results show that the proposed algorithm is feasible and has the potential to be used for implementation in the real environment
Beyond interfaces: A usability study of Chinese journal databases
No full textA presentation at the Council on East Asian Libraries (CEAL) annual meeting in Boston, MA on March 21, 2007
Rose Galaida and the Central China Relief Records, 1946: Discovery, Investigation, and Implications
No full textThe materials in the Central China Relief Records (CCRR) collection provide a window to the experiences of Rose Galaida in Hubei. The collection consists of about 100 documents totaling over 300 pages (excluding duplicate copies) and 5 photographs.Peer reviewedPublished in the Journal of East Asian Libraries and available from the journal at: https://scholarsarchive.byu.edu/jeal/vol2011/iss153/
Breaking New Ground in East Asia Library History
No full textReview of Peter X. Zhou. Collecting Asia: East Asian Libraries in North America (2010).Published in H-Net Reviews in the Humanities and Social Sciences and available at: http://www.h-net.org/reviews/showrev.php?id=32231March 201
One step preparation of pure tau-MnAl phase with high magnetization using strip casting method
No full textFerromagnetic phase of Mn-Al exhibits great potential in the rare-earth free permanent magnetic materials due to its high magnetocrystalline anisotropy, high magnetization, high Curie temperature and low cost. In this work, the strip casting technique was applied to prepare MnAl magnetic phase. X-ray diffraction and energy dispersive X-ray analyses indicate that the as-prepared Mn54Al46 strip sample consists of pure tau-MnAl magnetic phase. It is found that the composition of Mn54Al46 is suitable to prepare tau-MnAl phase during the strip casting process. The Mn54Al46 strip sample synthesized through the strip casting exhibits a fairly high magnetization of 114 emu/g under a field of 5 T, while the coercivity of iHc = 2.8 kOe, magnetization of M-5T = 63.9 emu/g at room temperature can be obtained for Mn54Al46 powder sample. This preparation method can produce a large amount of tau-phase MnAl alloy and promote mass industrialized production. (C) 2017 Author(s)
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