93,703 research outputs found
A dependency network description of building information models
The pervasive deployment of “smart building” projects world-wide is driving innovation on many fronts including; technology, telematics, engineering and entrepreneurship. This paper focuses on the technical and engineering perspectives of BIM, by extending building morphology studies as to respond to the challenges posed by Big Data, and smart infrastructure. The proposed framework incorporates theoretical and modelling descriptions to verify how network-based models can act as the backbone skeletal representation of building complexity, and yet relate to environmental performance and smart infrastructure. The paper provides some empirical basis to support data information models through building dependency networks as to represent the relationships between different existing and smart infrastructure components. These dependency networks are thought to inform decisions on how to represent building data sets in response to different social and environmental performance requirements, feeding that into void and solid descriptions of data maturity models. It is concluded that network-based models are fundamental to comprehend and represent the complexity of buildings and inform architectural design and public policy practices, in the design and operation phases of infrastructure projects
Avoidability of formulas with two variables
In combinatorics on words, a word over an alphabet is said to
avoid a pattern over an alphabet of variables if there is no
factor of such that where is a
non-erasing morphism. A pattern is said to be -avoidable if there exists
an infinite word over a -letter alphabet that avoids . We consider the
patterns such that at most two variables appear at least twice, or
equivalently, the formulas with at most two variables. For each such formula,
we determine whether it is -avoidable, and if it is -avoidable, we
determine whether it is avoided by exponentially many binary words
Accurate molecular polarizabilities with coupled-cluster theory and machine learning
The molecular polarizability describes the tendency of a molecule to deform
or polarize in response to an applied electric field. As such, this quantity
governs key intra- and inter-molecular interactions such as induction and
dispersion, plays a key role in determining the spectroscopic signatures of
molecules, and is an essential ingredient in polarizable force fields and other
empirical models for collective interactions. Compared to other ground-state
properties, an accurate and reliable prediction of the molecular polarizability
is considerably more difficult as this response quantity is quite sensitive to
the description of the underlying molecular electronic structure. In this work,
we present state-of-the-art quantum mechanical calculations of the static
dipole polarizability tensors of 7,211 small organic molecules computed using
linear-response coupled-cluster singles and doubles theory (LR-CCSD). Using a
symmetry-adapted machine-learning based approach, we demonstrate that it is
possible to predict the molecular polarizability with LR-CCSD accuracy at a
negligible computational cost. The employed model is quite robust and
transferable, yielding molecular polarizabilities for a diverse set of 52
larger molecules (which includes challenging conjugated systems, carbohydrates,
small drugs, amino acids, nucleobases, and hydrocarbon isomers) at an accuracy
that exceeds that of hybrid density functional theory (DFT). The atom-centered
decomposition implicit in our machine-learning approach offers some insight
into the shortcomings of DFT in the prediction of this fundamental quantity of
interest
Asymptotic Regge Trajectories of Non-strange Mesons
We analyze the asymptotic behavior of Regge trajectories of non-strange
mesons. In contrast to an existing belief, it is demonstrated that for the
asymptotically linear Regge trajectories the width of heavy hadrons cannot
linearly depend on their mass. Using the data on masses and widths of rho_J,
omega_J, a_J and f_J mesons for the spin values J \leq 6, we extract the
parameters of the asymptotically linear Regge trajectory predicted by the
finite width model of quark gluon bags. As it is shown the obtained parameters
for the data set B correspond to the cross-over temperature lying in the
interval 170.9-175.3 MeV which is consistent with the kinetic freeze-out
temperature of early hadronizing particles found in relativistic heavy ion
collisions at and above the highest SPS energy.Comment: 14 pages, 3 figure
T-cell responses in oiled guillemots and swans in a rehabilitation setting
This article has been accepted for publication in the Archives of Environmental Contamination and Toxicology. The final version can be accessed from the link below.This article has been made available through the Brunel Open Access Publishing Fund.Aquatic birds are commonly affected by oil spills. Despite rehabilitation efforts, the majority of rehabilitated common guillemots (Uria aalge) do not survive, whereas mute swans (Cygnus olor) tend to have higher post-release survival. Polyaromatic hydrocarbons (PAHs) present in crude oil and diesel are immunotoxic in birds affecting cell-mediated responses to immunogens. Because it is a target of PAH toxicity, T-lymphocyte response to controlled mitogen administration (phytohemagglutinnin test) was investigated in a scoping study as a potentially useful minimally invasive in vivo test of cell-mediated immunity. The test was performed on 69 mute swans and 31 common guillemots stranded on the Norfolk and Lincolnshire coastline and inland waterways in England (UK)either due to injury or to contamination with crude or diesel oil. T-lymphocyte response was significantly decreased in swans with greater oil scores. T-lymphocyte responses were also decreased in guillemots, but this finding was not statistically significant
Metastable Vacua in Superconformal SQCD-like Theories
We study dynamical supersymmetry breaking in vector-like superconformal N=1
gauge theories. We find appropriate deformations of the superpotential to
overcome the problem of the instability of the non supersymmetric vacuum. The
request for long lifetime translates into constraints on the physical couplings
which in this regime can be controlled through efficient RG analysis.Comment: 17 pages, 7 figures, JHEP3.cl
Injury Risk Estimation Expertise Assessing the ACL Injury Risk Estimation Quiz
Background: Available methods for screening anterior cruciate ligament (ACL) injury risk are effective but limited in application as
they generally rely on expensive and time-consuming biomechanical movement analysis. A potential efficient alternative to biomechanical
screening is skilled movement analysis via visual inspection (ie, having experts estimate injury risk factors based on
observations of athletes’ movements).
Purpose: To develop a brief, valid psychometric assessment of ACL injury risk factor estimation skill: the ACL Injury Risk Estimation
Quiz (ACL-IQ).
Study Design: Cohort study (diagnosis); Level of evidence, 3.
Methods: A total of 660 individuals participated in various stages of the study, including athletes, physicians, physical therapists,
athletic trainers, exercise science researchers/students, and members of the general public in the United States. The ACL-IQ was
fully computerized and made available online (www.ACL-IQ.org). Item sampling/reduction, reliability analysis, cross-validation,
and convergent/discriminant validity analysis were conducted to optimize the efficiency and validity of the assessment.
Results: Psychometric optimization techniques identified a short (mean time, 2 min 24 s), robust, 5-item assessment with high
reliability (test-retest: r = 0.90) and consistent discriminability (average difference of exercise science professionals vs general
population: Cohen d = 1.98). Exercise science professionals and general population individuals scored 74% and 53% correct,
respectively. Convergent and discriminant validity was demonstrated. Scores on the ACL-IQ were most associated with ACL
knowledge and various cue utilities and were least associated with domain-general spatial/decision-making ability, personality,
or other demographic variables. Overall, 23% of the total sample (40% exercise science professionals; 6% general population)
performed better than or equal to the ACL nomogram.
Conclusion: This study presents the results of a systematic approach to assess individual differences in ACL injury risk factor
estimation skill; the assessment approach is efficient (ie, it can be completed in\3 min) and psychometrically robust. The results
provide evidence that some individuals have the ability to visually estimate ACL injury risk factors more accurately than other
instrument-based ACL risk estimation methods (ie, ACL nomogram). The ACL-IQ provides the foundation for assessing the efficacy
of observational ACL injury risk factor assessment (ie, does simple skilled visual inspection reduce ACL injuries?). It also
provides a representative task environment that can be used to increase our understanding of the perceptual-cognitive mechanisms
underlying observational movement analysis and to improve injury risk assessment performance
Cyclic Coset Orbifolds
We apply the new orbifold duality transformations to discuss the special case
of cyclic coset orbifolds in further detail. We focus in particular on the case
of the interacting cyclic coset orbifolds, whose untwisted sectors are
Z_\lambda(permutation)-invariant g/h coset constructions which are not \lambda
copies of coset constructions. Because \lambda copies are not involved, the
action of Z_\lambda(permutation) in the interacting cyclic coset orbifolds can
be quite intricate. The stress tensors and ground state conformal weights of
all the sectors of a large class of these orbifolds are given explicitly and
special emphasis is placed on the twisted h subalgebras which are generated by
the twisted (0,0) operators of these orbifolds. We also discuss the systematics
of twisted (0,0) operators in general coset orbifolds.Comment: 30 page
- …