Microwave Induced Instability Observed in BSCCO 2212 in a Static Magnetic Field

We have measured the microwave dissipation at 10 GHz through the imaginary part of the susceptibility, $\chi^"$, in a BSCCO 2212 single crystal in an external static magnetic field $H$ parallel to the c-axis at various fixed temperatures. The characteristics of $\chi^"(H)$ exhibit a sharp step at a field $H_{step}$ which strongly depends on the amplitude of the microwave excitation $h_{ac}$. The characteristics of $h_{ac}$ vs. $H_{step}$, qualitatively reveal the behavior expected for the magnetic field dependence of Josephson coupling.Comment: 4 pages, 3 Postscript figure

Decision-making in façade selection for multi-storey buildings

The conference paper can be viewed at: http://www.arcom.ac.uk/-docs/proceedings/ar2012-0357-0367_Garmston_Pan_de%20Wilde.pdfThe design and construction of multi-storey buildings faces a multitude of demands such as aesthetics, cost, energy efficiency, and occupier comfort; with façades on both new and re-used buildings playing a key role in helping to meet these demands. The process of façade selection is aided by a plethora of decision-making tools, yet façade decisions are often largely guided by cost and aesthetics. Poorly specified façades can potentially expose developers, owners and occupiers of multi-storey buildings to risks such as poor thermal comfort, glare, and increased operational costs. The aim of this paper is to explore the current state of façade decision-making, with the objectives of discovering who is making the decisions and when, and what problems are perceived and what potential solutions might exist. Literature pertaining to façades, multi-storey buildings and façade decision-making is reviewed. Experience of façade decision-making in today’s construction industry in the UK is collected via semi-structured interviews with construction professionals. The findings show architects as leading the initial façade decisions, with clients and planners making the final decisions. Very few decision-making tools were revealed as being used: namely whole life cost analysis, life cycle cost analysis and simulation. Further research is proposed to define the roles participating in façade decision-making for multi-storey buildings

Multi-storey building retrofit with a focus on the façade selection process: A UK commercial office case study

Fulltext in: http://www.arcom.ac.uk/-docs/proceedings/ar2013-0081-0090_Garmston_Fox_Pan_de%20Wilde.pdfPoorly-insulated existing buildings contribute significantly to the energy use of the built environment. In the UK, the existing building stock is replaced at a rate of less than 2% a year; thus, many of today’s buildings will still be in use in 2060. Retrofitting aged buildings can significantly reduce their energy use. This paper analyses the selection process and success factors in retrofit façade decision-making. Literature relating to building retrofit and façade selection is reviewed. A case study is conducted on a five-storey 1970s UK commercial office building, retrofitted in 2011. Data is collected via in-depth interviews with key project decision-makers, a documentary evidence review, and thermography of the completed retrofitted façade. The façade evolution is mapped according to seven identified project stages and the RIBA Plan of Work 2007. The retrofit satisfied the client’s aesthetic needs, while delivering an 85% reduction in the ’wall’ U-value and a ’B’ rated Energy Performance Certificate. Value engineering (VE) greatly influenced the façade selection, with less expensive alternatives replacing original elements of the façade design. The façade’s thermal success is linked to the VE focusing on façade elements covering only a small extent of the building. Façade success factors key to attracting tenants (lower running costs and aesthetics) may apply to commercial buildings in general. Thermography aided in assessing the retrofitted thermal envelope, but to act as a tool to aid retrofit façade selection, it should ideally involve a ’before’ and ’after’ survey

The squashed entanglement of the noiseless quantum Gaussian attenuator and amplifier

We determine the maximum squashed entanglement achievable between sender and receiver of the noiseless quantum Gaussian attenuators and amplifiers and we prove that it is achieved sending half of an infinitely squeezed two-mode vacuum state. The key ingredient of the proof is a lower bound to the squashed entanglement of the quantum Gaussian states obtained applying a two-mode squeezing operation to a quantum thermal Gaussian state tensored with the vacuum state. This is the first lower bound to the squashed entanglement of a quantum Gaussian state and opens the way to determine the squashed entanglement of all quantum Gaussian channels. Moreover, we determine the classical squashed entanglement of the quantum Gaussian states above and show that it is strictly larger than their squashed entanglement. This is the first time that the classical squashed entanglement of a mixed quantum Gaussian state is determined