4,912 research outputs found
Industrial Parks in Russia: Conceptual Development of Projects
The paper presents a theoretical framework of industrial parks effectiveness as an element of economic policy to accelerate economy development in regions or municipalities. The article studies how historically such instruments were used in modern Russia. The paper states the necessity of extensive development of the industrial park concept and how it affects the chances of project realization and potential economic effectiveness. The main parts and blocks that should be taken into account during concept preparations are highlighted, and proposals for their content are made
Development of improved adhesives for use at cryogenic temperatures to minus423 deg F Final summary report, 11 Jul. 1963 - 31 Aug. 1965
Improved polyurethane and epoxy resins for use as adhesives at cryogenic temperature
Graphene zigzag ribbons, square lattice models and quantum spin chains
We present an extended study of finite-width zigzag graphene ribbons (ZGRs)
based on a tight-binding model with hard-wall boundary conditions. We provide
an exact analytic solution that clarifies the origin of the predicted width
dependence on the conductance through junctions of ribbons with different
widths. An analysis of the obtained solutions suggests a new description of
ZGRs in terms of coupled chains. We pursue these ideas further by introducing a
mapping between the ZGR model and the Hamiltonian for N-coupled quantum chains
as described in terms of 2N Majorana fermions. The proposed mapping preserves
the dependence of ribbon properties on its width thus rendering metallic
ribbons for N odd and zero-gap semiconductor ribbons for N even. Furthermore,
it reveals a close connection between the low-energy properties of the ZGR
model and a continuous family of square lattice model Hamiltonians with similar
width-dependent properties that includes the flux and the trivial square
lattice models. As a further extension, we show that this new description makes
it possible to identify various aspects of the physics of graphene ribbons with
those predicted by models of quantum spin chains (QSCs)
Tunable pseudogap Kondo effect and quantum phase transitions in Aharonov-Bohm interferometers
We study two quantum dots embedded in the arms of an Aharonov-Bohm ring
threaded by a magnetic flux. The system can be described by an effective
one-impurity Anderson model with an energy- and flux-dependent density of
states. For specific values of the flux, this density of states vanishes at the
Fermi energy, yielding a controlled realization of the pseudogap Kondo effect.
The conductance and transmission phase shifts reflect a nontrivial interplay
between wave interference and interactions, providing clear signatures of
quantum phase transitions between Kondo and non-Kondo ground states.Comment: Published versio
Signatures of quantum phase transitions in parallel quantum dots: Crossover from local-moment to underscreened spin-1 Kondo physics
We study a strongly interacting "quantum dot 1" and a weakly interacting "dot
2" connected in parallel to metallic leads. Gate voltages can drive the system
between Kondo-quenched and non-Kondo free-moment phases separated by
Kosterlitz-Thouless quantum phase transitions. Away from the immediate vicinity
of the quantum phase transitions, the physical properties retain signatures of
first-order transitions found previously to arise when dot 2 is strictly
noninteracting. As interactions in dot 2 become stronger relative to the
dot-lead coupling, the free moment in the non-Kondo phase evolves smoothly from
an isolated spin-one-half in dot 1 to a many-body doublet arising from the
incomplete Kondo compensation by the leads of a combined dot spin-one. These
limits, which feature very different spin correlations between dot and lead
electrons, can be distinguished by weak-bias conductance measurements performed
at finite temperatures.Comment: 7 pages, 7 figures. Accepted for publication in Phys. Rev.
Zero-field Kondo splitting and quantum-critical transition in double quantum dots
Double quantum dots offer unique possibilities for the study of many-body
correlations. A system containing one Kondo dot and one effectively
noninteracting dot maps onto a single-impurity Anderson model with a structured
(nonconstant) density of states. Numerical renormalization-group calculations
show that while band filtering through the resonant dot splits the Kondo
resonance, the singlet ground state is robust. The system can also be
continuously tuned to create a pseudogapped density of states and access a
quantum critical point separating Kondo and non-Kondo phases.Comment: 4 pages, 4 figures; Accepted for publication in Physical Review
Letter
Novel Methods in Facilitating Audience and Performer Interaction Using the Mood Conductor Framework
While listeners’ emotional response to music is the subject of numerous studies, less attention is paid to the dynamic emotion variations due to the interaction between artists and audiences in live improvised music performances. By opening a direct communication channel from audience members to performers, the Mood Conductor system provides an experimental framework to study this phenomenon. Mood Conductor facilitates interactive performances and thus also has an inherent entertainment value. The framework allows audience members to send emotional directions using their mobile devices in order to “conduct” improvised performances. Emotion coordinates indicted by the audience in the arousal-valence space are aggregated and clustered to create a video projection. This is used by the musicians as guidance, and provides visual feedback to the audience. Three different systems were developed and tested within our framework so far. These systems were trialled in several public performances with different ensembles. Qualitative and quantitative evaluations demonstrated that musicians and audiences were highly engaged with the system, and raised new insights enabling future improvements of the framework
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