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High-Performance Integrated Window and Façade Solutions for California
The researchers developed a new generation of high-performance façade systems and supporting design and management tools to support industry in meeting Californiaâs greenhouse gas reduction targets, reduce energy consumption, and enable an adaptable response to minimize real-time demands on the electricity grid. The project resulted in five outcomes: (1) The research team developed an R-5, 1-inch thick, triplepane, insulating glass unit with a novel low-conductance aluminum frame. This technology can help significantly reduce residential cooling and heating loads, particularly during the evening. (2) The team developed a prototype of a windowintegrated local ventilation and energy recovery device that provides clean, dry fresh air through the façade with minimal energy requirements. (3) A daylight-redirecting louver system was prototyped to redirect sunlight 15â40 feet from the window. Simulations estimated that lighting energy use could be reduced by 35â54 percent without glare. (4) A control system incorporating physics-based equations and a mathematical solver was prototyped and field tested to demonstrate feasibility. Simulations estimated that total electricity costs could be reduced by 9-28 percent on sunny summer days through adaptive control of operable shading and daylighting components and the thermostat compared to state-of-the-art automatic façade controls in commercial building perimeter zones. (5) Supporting models and tools needed by industry for technology R&D and market transformation activities were validated. Attaining Californiaâs clean energy goals require making a fundamental shift from todayâs ad-hoc assemblages of static components to turnkey, intelligent, responsive, integrated building façade systems. These systems offered significant reductions in energy use, peak demand, and operating cost in California
Controllable Non-Markovianity for a Spin Qubit in Diamond
We present a flexible scheme to realize non-artificial non-Markovian dynamics
of an electronic spin qubit, using a nitrogen-vacancy center in diamond where
the inherent nitrogen spin serves as a regulator of the dynamics. By changing
the population of the nitrogen spin, we show that we can smoothly tune the
non-Markovianity of the electron spin's dynamic. Furthermore, we examine the
decoherence dynamics induced by the spin bath to exclude other sources of
non-Markovianity. The amount of collected measurement data is kept at a minimum
by employing Bayesian data analysis. This allows for a precise quantification
of the parameters involved in the description of the dynamics and a prediction
of so far unobserved data points.Comment: 12 pages, 9 figure, including supplemental materia
DIAMONDS: a new Bayesian Nested Sampling tool. Application to Peak Bagging of solar-like oscillations
To exploit the full potential of Kepler light curves, sophisticated and
robust analysis tools are now required more than ever. Characterizing single
stars with an unprecedented level of accuracy and subsequently analyzing
stellar populations in detail are fundamental to further constrain stellar
structure and evolutionary models. We developed a new code, termed Diamonds,
for Bayesian parameter estimation and model comparison by means of the nested
sampling Monte Carlo (NSMC) algorithm, an efficient and powerful method very
suitable for high-dimensional and multi-modal problems. A detailed description
of the features implemented in the code is given with a focus on the novelties
and differences with respect to other existing methods based on NSMC. Diamonds
is then tested on the bright F8 V star KIC~9139163, a challenging target for
peak-bagging analysis due to its large number of oscillation peaks observed,
which are coupled to the blending that occurs between peaks, and the
strong stellar background signal. We further strain the performance of the
approach by adopting a 1147.5 days-long Kepler light curve. The Diamonds code
is able to provide robust results for the peak-bagging analysis of KIC~9139163.
We test the detection of different astrophysical backgrounds in the star and
provide a criterion based on the Bayesian evidence for assessing the peak
significance of the detected oscillations in detail. We present results for 59
individual oscillation frequencies, amplitudes and linewidths and provide a
detailed comparison to the existing values in the literature. Lastly, we
successfully demonstrate an innovative approach to peak bagging that exploits
the capability of Diamonds to sample multi-modal distributions, which is of
great potential for possible future automatization of the analysis technique.Comment: 22 pages, 14 figures, 3 tables. Accepted for publication in A&
The Imperative of the Metastudio
The activities we engage in when we design form a broad and disparate palette. We explore, research, make marks, make artefacts, experiment, review, discuss, critique, assess. The âhomeâ of this palette of activities is âthe studioâ; a combination of laboratory, library, workshop, forum, exhibition.
It became apparent a few years ago, that the nature of the central plank of the studio dialogue, the tutorial, was changing. Students were bringing a wider range of media to the tutorial to represent their developing ideas. Importantly, this included, increasingly, electronic media, typically âliveâ CAD models on laptops.
As a tutor, the importance of the internet in tutorials, to share material, images, precedent with students, was also increasing. The tutorial was enriched. But it was harder to organise, and particularly it was harder to record, to provide a cohesive log of the dialogue, the feedback, the references. Much of the feedback in tutorial is drawn, and drawn freehand, in quick and dirty, intuitive mode.
It became apparent that it would be very helpful to find a way of pulling this melee of feedback and discussion together, of organising it for students and staff, but retaining the immediacy of the quick and dirty drawn discussion and freehand feedback
Accurate reconstruction of insertion-deletion histories by statistical phylogenetics
The Multiple Sequence Alignment (MSA) is a computational abstraction that
represents a partial summary either of indel history, or of structural
similarity. Taking the former view (indel history), it is possible to use
formal automata theory to generalize the phylogenetic likelihood framework for
finite substitution models (Dayhoff's probability matrices and Felsenstein's
pruning algorithm) to arbitrary-length sequences. In this paper, we report
results of a simulation-based benchmark of several methods for reconstruction
of indel history. The methods tested include a relatively new algorithm for
statistical marginalization of MSAs that sums over a stochastically-sampled
ensemble of the most probable evolutionary histories. For mammalian
evolutionary parameters on several different trees, the single most likely
history sampled by our algorithm appears less biased than histories
reconstructed by other MSA methods. The algorithm can also be used for
alignment-free inference, where the MSA is explicitly summed out of the
analysis. As an illustration of our method, we discuss reconstruction of the
evolutionary histories of human protein-coding genes.Comment: 28 pages, 15 figures. arXiv admin note: text overlap with
arXiv:1103.434
Band-pass filtering of the time sequences of spectral parameters for robust wireless speech recognition
In this paper we address the problem of automatic speech recognition when wireless speech communication systems are involved. In this context, three main sources of distortion should be considered: acoustic environment, speech coding and transmission errors. Whilst the first one has already received a lot of attention, the last two deserve further investigation in our opinion. We have found out that band-pass filtering of the recognition features improves ASR performance when distortions due to these particular communication systems are present. Furthermore, we have evaluated two alternative configurations at different bit error rates (BER) typical of these channels: band-pass filtering the LP-MFCC parameters or a modification of the RASTA-PLP using a sharper low-pass section perform consistently better than LP-MFCC and RASTA-PLP, respectively.Publicad
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