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Comparative numerical analysis for cost and embodied carbon optimisation of steel building structures
The study investigates an area of sustainable structural design that is often overlooked in practical engineering applications. Specifically, a novel method to optimise the cost and embodied carbon performance of steel building structures simultaneously is explored in this paper. To achieve this, a parametric design model was developed to rapidly analyse code compliant structural configurations based on project specific constraints and rigorous testing of multiple steel beams (UB sections), floor construction typologies (precast or composite) and column layouts that could not be performed manually by engineering practitioners. Detailed objective functions are embedded in the model to compute the cost and life cycle carbon emissions of different material types used in the structure. Results from a comparative numerical analysis of a real case study illustrate that the proposed optimisation approach could guide structural engineers towards areas of the solution space with realistic design configurations, enabling them to effectively evaluate cost and carbon trade-offs. This significant contribution implies that the optimisation model could reduce the time required for the design and analysis of multiple structural configurations especially during the early stages of a project. Overall, the paper suggests that the deployment of automated design procedures can enhance the quality as well as the efficiency of the optimisation analysis.The research described in this paper was financially supported by Innovate UK through the ‘Innovative engineering approach for material, carbon and cost efficiency of steel buildings’ project with reference number 10247
On the Numerical Evaluation of Loop Integrals With Mellin-Barnes Representations
An improved method is presented for the numerical evaluation of multi-loop
integrals in dimensional regularization. The technique is based on
Mellin-Barnes representations, which have been used earlier to develop
algorithms for the extraction of ultraviolet and infrared divergencies. The
coefficients of these singularities and the non-singular part can be integrated
numerically. However, the numerical integration often does not converge for
diagrams with massive propagators and physical branch cuts. In this work,
several steps are proposed which substantially improve the behavior of the
numerical integrals. The efficacy of the method is demonstrated by calculating
several two-loop examples, some of which have not been known before.Comment: 13 pp. LaTe
Bi-allelic mutations in uncoordinated mutant number-45 myosin chaperone B are a cause for congenital myopathy
Congenital myopathies (CM) form a genetically heterogeneous group of disorders characterized by perinatal muscle weakness. Here, we report an 11-year old male offspring of consanguineous parents of Lebanese origin. He presented with proximal weakness including Gower's sign, and skeletal muscle biopsy revealed myopathic changes with core-like structures. Whole exome sequencing of this index patient lead to the discovery of a novel genetically defined CM subtype based on bi-allelic mutations in the uncoordinated mutant number-45 myosin chaperone B (UNC45B) NM_173167:c.2261G > A, p.Arg754Gln. The mutation is conserved in evolution and co-segregates within the pedigree with the phenotype, and located in the myosin binding armadillo repeat domain 3 (ARM3), and has a CADD Score of 35. On a multimeric level, UNC45B aggregates to a chain which serves as an assembly line and functions as a template defining the geometry, regularity, and periodicity of myosin arranged into muscle thick filaments. Our discovery is in line with the previously described myopathological phenotypes in C. elegans and in vertebrate mutants and knockdown-models. In conclusion, we here report for the first time a patient with an UNC45B mutation causing a novel genetically defined congenital myopathy disease entity
Dissipative systems: uncontrollability, observability and RLC realizability
The theory of dissipativity has been primarily developed for controllable
systems/behaviors. For various reasons, in the context of uncontrollable
systems/behaviors, a more appropriate definition of dissipativity is in terms
of the dissipation inequality, namely the {\em existence} of a storage
function. A storage function is a function such that along every system
trajectory, the rate of increase of the storage function is at most the power
supplied. While the power supplied is always expressed in terms of only the
external variables, whether or not the storage function should be allowed to
depend on unobservable/hidden variables also has various consequences on the
notion of dissipativity: this paper thoroughly investigates the key aspects of
both cases, and also proposes another intuitive definition of dissipativity.
We first assume that the storage function can be expressed in terms of the
external variables and their derivatives only and prove our first main result
that, assuming the uncontrollable poles are unmixed, i.e. no pair of
uncontrollable poles add to zero, and assuming a strictness of dissipativity at
the infinity frequency, the dissipativities of a system and its controllable
part are equivalent. We also show that the storage function in this case is a
static state function.
We then investigate the utility of unobservable/hidden variables in the
definition of storage function: we prove that lossless autonomous behaviors
require storage function to be unobservable from external variables. We next
propose another intuitive definition: a behavior is called dissipative if it
can be embedded in a controllable dissipative {\em super-behavior}. We show
that this definition imposes a constraint on the number of inputs and thus
explains unintuitive examples from the literature in the context of
lossless/orthogonal behaviors.Comment: 26 pages, one figure. Partial results appeared in an IFAC conference
(World Congress, Milan, Italy, 2011
Passive water control at the surface of a superhydrophobic lichen
Some lichens have a super-hydrophobic upper surface, which repels water drops, keeping the surface dry but probably preventing water uptake. Spore ejection requires water and is most efficient just after rainfall. This study was carried out to investigate how super-hydrophobic lichens manage water uptake and repellence at their fruiting bodies, or podetia. Drops of water were placed onto separate podetia of Cladonia chlorophaea and observed using optical microscopy and cryo-scanning-electron microscopy (cryo-SEM) techniques to determine the structure of podetia and to visualise their interaction with water droplets. SEM and optical microscopy studies revealed that the surface of the podetia was constructed in a three-level structural hierarchy. By cryo-SEM of water-glycerol droplets placed on the upper part of the podetium, pinning of the droplet to specific, hydrophilic spots (pycnidia/apothecia) was observed. The results suggest a mechanism for water uptake, which is highly sophisticated, using surface wettability to generate a passive response to different types of precipitation in a manner similar to the Namib Desert beetle. This mechanism is likely to be found in other organisms as it offers passive but selective water control
Simple Observables from Fat Link Fermion Actions
A comparison is made of the (quenched) light hadron spectrum and of simple
matrix elements for a hypercubic fermion action (based on a fixed point action)
and the clover action, both using fat links, at a lattice spacing a= 0.18 fm.
Renormalization constants for the naive and improved vector current and the
naive axial current are computed using Ward identities. The renormalization
factors are very close to unity, and the spectroscopy of light hadrons and the
pseudoscalar and vector decay constants agree well with simulations at smaller
lattice spacings (and with experiment).Comment: 22 pages, 12 postscript figures, Revtex plus eps
Random-Matrix Theory of Quantum Size Effects on Nuclear Magnetic Resonance in Metal Particles
The distribution function of the local density of states is computed exactly
for the Wigner-Dyson ensemble of random Hamiltonians. In the absence of
time-reversal symmetry, precise agreement is obtained with the "supersymmetry"
theory by Efetov and Prigodin of the NMR lineshape in disordered metal
particles. Upon breaking time-reversal symmetry, the variance of the Knight
shift in the smallest particles is reduced by a universal factor of 2/3. ***To
be published in Physical Review B.****Comment: 4 pages, REVTeX-3.0, 1 postscript figure, INLO-PUB-940819; [2017:
figure included in text
Contribution of local agrobiodiversity to complementary foods for 6 to 23 months old children in southern rural Benin
In rural Benin, malnutrition, especially micronutrient deficiencies, contrasts with a rich agrobiodiversity that abounds in cultivated or wild foods that are potential sources of micronutrients. This paradox leads us to examine the role of local agrobiodiversity in the diet of children living in two agroecological zones of southern Benin. This study involved 1,263 children aged 6-23 months from 17 randomly selected villages in Southern Benin. A multiple-pass 24-h recall method on two non-consecutive days with the estimation of the consumed portions was used to collect dietary intake data. Semistructured questionnaires were used to collect socioeconomic and demographic data to explore factors driving agrobiodiversity food consumption, especially wild foods. Nonparametric analyses based on gamma distribution were performed to establish the effect of wild food consumption on vitamin A, calcium, iron, and zinc intakes. Conditional inference tree-classification models were performed to identify factors driving wild food consumption. Among a total of 48 local foods that were reported as consumed by children, 11 were from wild species. The contributions of total local agrobiodiversity to nutrient intake of complementary foods was between 49% (calcium) and 98% (vitamin A). Cultivated species contributed to local agrobiodiversity foods for 57% (calcium) and 96 % (zinc). The semi-domesticated species have a contribution of between 2% (zinc) and 35% (calcium) to nutrient intake. Wild species contribution to nutrient intake was between 1% (zinc) and 9% for vitamin C. Wild foods consumption correlated significantly and positively with calcium and vitamin A intakes among children. Sociolinguistic factors such as ethnicity and religion of the household head were determinants of wild food consumption. These findings suggest that sensitization on the nutritional importance of the wild foods including socio-linguistic factors may be necessary to promote wild foods’ consumption. This could be a good strategy to promote healthy diets in local communities. 
Rotational master equation for cold laser-driven molecules
The equations of motion for the molecular rotation are derived for
vibrationally cold dimers that are polarized by off-resonant laser light. It is
shown that, by eliminating electronic and vibrational degrees of freedom, a
quantum master equation for the reduced rotational density operator can be
obtained. The coherent rotational dynamics is caused by stimulated Raman
transitions, whereas spontaneous Raman transitions lead to decoherence in the
motion of the quantized angular momentum. As an example the molecular dynamics
for the optical Kerr effect is chosen, revealing decoherence and heating of the
molecular rotation.Comment: 11 pages, 5 figures, to appear in Phys. Rev.
A Definitive Signal of Multiple Supersymmetry Breaking
If the lightest observable-sector supersymmetric particle (LOSP) is charged
and long-lived, then it may be possible to indirectly measure the Planck mass
at the LHC and provide a spectacular confirmation of supergravity as a symmetry
of nature. Unfortunately, this proposal is only feasible if the gravitino is
heavy enough to be measured at colliders, and this condition is in direct
conflict with constraints from big bang nucleosynthesis (BBN). In this work, we
show that the BBN bound can be naturally evaded in the presence of multiple
sectors which independently break supersymmetry, since there is a new decay
channel of the LOSP to a goldstino. Certain regions of parameter space allow
for a direct measurement of LOSP decays into both the goldstino and the
gravitino at the LHC. If the goldstino/gravitino mass ratio is measured to be
2, as suggested by theory, then this would provide dramatic verification of the
existence of multiple supersymmetry breaking and sequestering. A variety of
consistent cosmological scenarios are obtained within this framework. In
particular, if an R symmetry is imposed, then the gauge-gaugino-goldstino
interaction vertices can be forbidden. In this case, there is no bound on the
reheating temperature from goldstino overproduction, and thermal leptogenesis
can be accommodated consistently with gravitino dark matter.Comment: 10 pages, 5 figures, title changed to match the version published in
JHE
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