arXiv subjects

Tao Zhang

Publications and source records attributed to Tao Zhang.

684 records · Page 38Linked to original sources

arXiv2013

Modelling the Effects of User Learning on Forced Innovation Diffusion

Technology adoption theories assume that users' acceptance of an innovative technology is on a voluntary basis. However, sometimes users are force to accept an innovation. In this case users have to learn what it is useful for and how to use it. This learning process will enable users to transit from zero knowledge about the innovation to making the best use of it. So far the effects of user learning on technology adoption have received little research attention. In this paper - for the first time - we investigate the effects of user learning on forced innovation adoption by using an agent-based simulation approach using the case of forced smart metering deployments in the city of Leeds

cs.CY↗

arXiv2013

Deformations of Lie 2-algebras

In this paper, we consider deformations of Lie 2-algebras via the cohomology theory. We prove that a 1-parameter infinitesimal deformation of a Lie 2-algebra $\g$ corresponds to a 2-cocycle of $\g$ with the coefficients in the adjoint representation. The Nijenhuis operator for Lie 2-algebras is introduced to describe trivial deformations. We also study abelian extensions of Lie 2-algebras from the viewpoint of deformations of semidirect product Lie 2-algebras.

math-ph↗

arXiv2013

Modelling Electricity Consumption in Office Buildings: An Agent Based Approach

In this paper, we develop an agent-based model which integrates four important elements, i.e. organisational energy management policies/regulations, energy management technologies, electric appliances and equipment, and human behaviour, to simulate the electricity consumption in office buildings. Based on a case study, we use this model to test the effectiveness of different electricity management strategies, and solve practical office electricity consumption problems. This paper theoretically contributes to an integration of the four elements involved in the complex organisational issue of office electricity consumption, and practically contributes to an application of an agent-based approach for office building electricity consumption study.

cs.CE↗

arXiv2013

A Three-Dimensional Model of Residential Energy Consumer Archetypes for Local Energy Policy Design in the UK

This paper reviews major studies in three traditional lines of research in residential energy consumption in the UK, i.e. economic/infrastructure, behaviour, and load profiling. Based on the review the paper proposes a three-dimensional model for archetyping residential energy consumers in the UK by considering property energy efficiency levels, the greenness of household behaviour of using energy, and the duration of property daytime occupancy. With the proposed model, eight archetypes of residential energy consumers in the UK have been identified. They are: pioneer greens, follower greens, concerned greens, home stayers, unconscientious wasters, regular wasters, daytime wasters, and disengaged wasters. Using a case study, these archetypes of residential energy consumers demonstrate the robustness of the 3-D model in aiding local energy policy/intervention design in the UK.

cs.CY↗

arXiv2013

Comodule Hom-coalgebras

We introduce the concept of comodule Hom-coalgebras and show that comodule Hom-coalgebras can be deformed from comodule coalgebras via endomorphisms.

math.QA↗

arXiv2013

Omni-Lie Superalgebras and Lie 2-superalgebras

We introduce the notion of omni-Lie superalgebra as a super version of the omni-Lie algebra introduced by Weinstein. This algebraic structure gives a nontrivial example of Leibniz superalgebra and Lie 2-superalgebra. We prove that there is a one-to-one correspondence between Dirac structures of the omni-Lie superalgebra and Lie superalgebra structures on subspaces of a super vector space.

math.RA↗

arXiv2012

Watt-level ultrahigh-OSNR single-longitudinal-mode tunable Brillouin fiber laser

A watt-level ultrahigh optical signal-to-noise ratio (OSNR) single-longitudinal-mode (SLM) tunable Brillouin fiber laser (BFL) has been demonstrated.By optimizing the length of the single mode fiber (SMF) cavity at 11m and its output ratio at sixty percent, 1.04 W output power, as well as stable SLM operation is obtained at 2.24 W pump power. The single pass cavity BFL has the advantage that Brillouin pump frequency doesn't need to match the cavity mode, thus the stability is greatly improved. As only SMF is used in the cavity, the operate wavelength can be tunable without the restriction from self lasing cavity mode. Furthermore, it proves that core-pumped single frequency fiber laser is able to generate watt-level power. The laser has excellent performance in terms of noise, linewidth, and stability.

physics.optics↗

arXiv2012

Field test of the wavelength-saving quantum key distribution network

We propose a wavelength-saving topology of quantum key distribution(QKD) network based on passive optical elements, and report the field test of this network on the commercial telecom optical fiber. In this network, 5 nodes are supported with 2 wavelengths, and every two nodes can share secure keys directly at the same time. All QKD links in the network operate at the frequency of 20 MHz. We also characterized the insertion loss and crosstalk effects on the point-to-point QKD system after introducing this QKD network.

quant-ph↗

arXiv2011

Impurity effect on weak anti-localization in the topological insulator Bi2Te3

We study weak anti-localization (WAL) effect in topological insulator Bi2Te3 thin films at low temperatures. Two-dimensional WAL effect associated with surface carriers is revealed in the tilted magnetic field dependence of magneto-conductance. Our data demonstrates that the observed WAL is robust against deposition of non-magnetic Au impurities on the surface of the thin films. But it is quenched by deposition of magnetic Fe impurities which destroy the pi Berry's phase of the topological surface states. The magneto-conductance data of a 5 nm Bi2Te3 film suggests that a crossover from symplectic to unitary classes is observed with the deposition of Fe impurities.

cond-mat.mes-hall↗

arXiv2011

Bright Chirp-free and Chirped Nonautonomous solitons under Dispersion and Nonlinearity Management

We present a series of chirp-free and chirped analytical nonautonomous soliton solutions to the generalized nonlinear Schrodinger equation (NLSE) with distributed coefficients by Darboux transformation from a trivial seed. For chirpfree nonautonomous soliton, the dispersion management term can change the motion of nonautonomous soliton and do not affect its shape at all. Especially,the classical optical soliton can be presented with variable dispersion term and nonlinearity when there is no gain. For chirped nonautonomous soliton, dispersion management can affect the shape and motion of nonautonomous solitons meanwhile. The periodic dispersion term can be used to control its "breathing" shape, and it does not affect the trajectory of nonautonomous soliton center with a certain condition.

physics.optics↗

arXiv2008

Robust quantum cryptography with a heralded single-photon source based on the decoy-state method

In this paper, we describe a robust quantum cryptography scheme with a heralded single photon source based on the decoy-state method, which has been shown by numerical simulations to be advantageous compared with many other practical schemes not only with respect to the secure key generation rate but also to secure transmission distance. We have experimentally tested this scheme, and the results support the conclusions from numerical simulations well. Although there still exist many deficiencies in our present systems, it's still sufficient to demonstrate the advantages of the scheme. Besides, even when cost and technological feasibility are taken into account, our scheme is still quite promising in the implementation of tomorrow's quantum cryptography.

quant-ph↗

arXiv2007

Field Experimental "Star Type" Metropolitan Quantum Key Distribution Network

Quantum key distribution (QKD) network has recently attracted growing attentions. Due to the special characteristics of quantum information, to build a full-connectivity QKD network without trusted relays is a stimulating challenge. In this letter, we report on the first realization of QKD network without trusted relays which covers metropolis in the commercial backbone optical fiber networks. The star topology four-user QKD network automatically addresses the quantum signal with a quantum router (QR) and every user in the network can receive and distribute quantum keys to any others simultaneously. The longest and the shortest length of fibers between two geographically separated nodes are 42.6km and 32km respectively, and the maximum average quantum bit error rate (QBER) is below 8%. This result opens a new possibility for the use of QKD into existing network.

quant-ph↗

arXiv2007

Double Bicrosssum of Braided Lie algebras

The condition for double bicrosssum to be a braided Lie bialgebra is given. The result generalizes quantum double, bicrosssum, bicrosscosum, bisum. The quantum double of braided Lie bialgebras is constructed. The relation between double crosssum of Lie algebras and double crossproduct of Hopf algebras is given.

math.QA↗

arXiv2006

Lanthanum-Cerium Based Bulk Metallic Glasses with Superior Glass-Forming Ability

A quinary (La0.5Ce0.5)65Al10(Co0.6Cu0.4)25 alloy with superior glass-forming ability (GFA), identified by the formation of fully glassy rod of 32 mm in diameter by tilt-pour casting, was reported. By comparing with the GFA of quarternary (La0.5Ce0.5)65Al10TM25 and ternary Ln65Al10TM25 alloys (Ln = La or Ce; TM = Co or Cu), we suggest that the strong frustration of crystallization by utilizing the coexistence of La-Ce and Co-Cu to complicate competing crystalline phases is helpful to construct BMG component with superior GFA.

cond-mat.mtrl-sci↗

arXiv2006

Influence of Similar Atom Substitution on Glass Formation in (La-Ce)-Al-Co Bulk Metallic Glasses

The glass-formation range of bulk metallic glasses (BMGs) based on lanthanum and cerium was pinpointed in La-Al-Co, Ce-Al-Co and pseudo-ternary (La-Ce)-Al-Co system respectively by copper mold casting. Through the stepwise substitution of La for solvent Ce in (LaxCe1-x)65Al10Co25 alloys (0<x<1), the fully glassy rods of the (La0.7Ce0.3)65Al10Co25 alloy can be successfully produced up to 25 mm in diameter by tilt-pour casting. Comparing with the glass-forming ability (GFA) of single-lanthanide based alloys, La65Al10Co25 and Ce65Al10Co25, the coexistence of La and Ce with similar atomic size and various valence electronic structure can obviously improve the GFA of (LaxCe1-x)65Al10Co25 BMGs, which can't be explained by the former GFA criteria for BMGs, e.g. atomic size mismatch and negative heats of mixing. A thermodynamic model was proposed to evaluate this substitution effect, which gives a reasonable explanation for the obvious improvement of GFA induced by the coexistence of similar atoms.

cond-mat.mtrl-sci↗

arXiv2006

Quantum key distribution network with wavelength addressing

Most traditional applications of quantum cryptography are point-to-point communications, in which only two users can exchange keys. In this letter, we present a network scheme that enable quantum key distribution between multi-user with wavelength addressing. Considering the current state of wavelength division multiplexing technique, dozens or hundreds of users can be connected to such a network and directly exchange keys with each other. With the scheme, a 4-user demonstration network was built up and key exchanges were performed.

quant-ph↗

arXiv2006

Extensible router for multi-user quantum key distribution network

A feasible quantum key distribution (QKD) network scheme has been proposed with the wavelength routing. An apparatus called "quantum router", which is made up of many wavelength division multiplexers, can route the quantum signals without destroying their quantum states. Combining with existing point-to-point QKD technology, we can setup a perfectly QKD star-network. A simple characteristic and feasibility of this scheme has also been obtained.

quant-ph↗

arXiv2006

Nonlocality-controlled interaction of spatial solitons in nematic liquid crystals

We demonstrate experimentally that the interactions between a pair of nonlocal spatial optical solitons in a nematic liquid crystal (NLC) can be controlled by the degree of nonlocality. For a given beam width, the degree of nonlocality can be modulated by varying the pretilt angle of NLC molecules via the change of the bias. When the pretilt angle is smaller than pi/4, the nonlocality is strong enough to guarantee the independence of the interactions on the phase difference of the solitons. As the pretilt angle increases, the degree of nonlocality decreases. When the degree is below its critical value, the two solitons behavior in the way like their local counterpart: the two in-phase solitons attract and the two out-of-phase solitons repulse.

physics.optics↗