685 research outputs found
URBAN DESIGN STRATEGIES FOR THE UPCYCLING OF URBAN INFRASTRUCTURE RESIDUAL POCKETS: 3D CITY MODELLING FROM OPEN DATA AND LOW-COST RAPID MAPPING TOOLS
This paper deals with the 3D City Modelling specific procedure developed as a tool to support strategies for urban regeneration, within the framework of the B-ROAD research project.The B-ROAD research project, whose acronym stands for Below the Road, is developing urban design strategies for upcycling urban infrastructure residual pockets.The B-ROAD’s methodology is conceived as research by design as it is carried out by creating pilot scenarios, disclosing the latent and still unexpressed potential of these wasted areas and displaying their potential transformations, to turn them into precious resources for the contemporary city.The 3D City Modelling of the study area has proved to be essential and strategic yet often complex and critical as most of the spatial and architectural features of B-ROAD spaces, as well as their potential, cannot be detected nor represented through the traditional means of representation of urbanised land, as aerial survey-based representations, or GIS. Likewise, traditional, or even cutting-edge, survey techniques that can be used to acquire missing data are often costly and time-consuming, thus making it hardly impossible to achieve the purpose of extensive and deep knowledge of such a vast area. Thus, 3D City Modelling aimed at examining spaces and providing a final representation of pilot scenarios has been a crucial stage requiring a specific in-depth study.</p
FAST SURVEY PROCEDURES IN URBAN SCENARIOS: SOME TESTS WITH 360° CAMERAS
The use of spherical cameras (with a field of view of 360°) is becoming increasingly popular for photogrammetric applications characterised by the opportunity to capture entire scenes in a relatively short time.This potential may be even more interesting for the digitisation of complex areas where, in addition to geometry, time, cost and social context play an important role.This contribution is part of this field of investigation by describing two experiments conducted on the use of an inexpensive 360° camera, the Insta360 OneX2, for the expeditious survey of residual spaces below road junctions.The area under investigation is a node in the city of Naples (Italy) located in the eastern area, considered particularly significant for the interaction between the geographical and infrastructural system.Two different approaches are tested starting from the acquisition of the spherical photographic dataset: the traditional one by means of photogrammetric software and the more economical and user-friendly one by employing the Matterport Capture application. Pros and cons of the two approaches are discussed: the first experimental results are encouraged and support the validity of the approach for surveying complex urban spaces.</p
Inclined Surface Locomotion Strategies for Spherical Tensegrity Robots
This paper presents a new teleoperated spherical tensegrity robot capable of
performing locomotion on steep inclined surfaces. With a novel control scheme
centered around the simultaneous actuation of multiple cables, the robot
demonstrates robust climbing on inclined surfaces in hardware experiments and
speeds significantly faster than previous spherical tensegrity models. This
robot is an improvement over other iterations in the TT-series and the first
tensegrity to achieve reliable locomotion on inclined surfaces of up to
24\degree. We analyze locomotion in simulation and hardware under single and
multi-cable actuation, and introduce two novel multi-cable actuation policies,
suited for steep incline climbing and speed, respectively. We propose
compelling justifications for the increased dynamic ability of the robot and
motivate development of optimization algorithms able to take advantage of the
robot's increased control authority.Comment: 6 pages, 11 figures, IROS 201
Magnetic resonance imaging landmarks for preoperative localization of inferior medial genicular artery: a proof of concept analysis
The joint line is a useful landmark to identify IMGAcourse during knee surgery. The IMGA course is closerto the joint line and to the border of the medial tibialplateau in females than in males. Although the interindi-vidual variability these results should be taken into ac-count when performing all surgical procedures involvingthe medial aspect of the knee. Similar interindividualdistances were observed between IMGA and semimem-branosus tendon insertion regardless of gender. How-ever, the proximity to this tendon should be consideredespecially during specific cases of ligamentous balancingin TKA procedure
DROM: Enabling Efficient and Effortless Malleability for Resource Managers
In the design of future HPC systems, research in resource management is showing an increasing interest in a more dynamic control of the available resources. It has been proven that enabling the jobs to change the number of computing resources at run time, i.e. their malleability, can significantly improve HPC system performance. However, job schedulers and applications typically do not support malleability due to the common belief that it introduces additional programming complexity and performance impact. This paper presents DROM, an interface that provides efficient malleability with no effort for program developers. The running application is enabled to adapt the number of threads to the number of assigned computing resources in a completely transparent way to the user through the integration of DROM with standard programming models, such as OpenMP/OmpSs, and MPI. We designed the APIs to be easily used by any programming model, application and job scheduler or resource manager. Our experimental results from two realistic use cases analysis, based on malleability by reducing the number of cores a job is using per node and jobs co-allocation, show the potential of DROM for improving the performance of HPC systems. In particular, the workload of two MPI+OpenMP neuro-simulators are tested, reporting improvement in system metrics, such as total run time and average response time, up to 8% and 48%, respectively.This work is partially supported by the Span-
ish Government through Programa Severo Ochoa (SEV-2015-0493), by the Spanish Ministry of Science and Technology through TIN2015-65316-P project, by the Generalitat de Catalunya (contract 2017-SGR-1414) and from the European Union’s Horizon 2020 under grant agreement No 785907 (HBP SGA2)Peer ReviewedPostprint (author's final draft
Holistic Slowdown Driven Scheduling and Resource Management for Malleable Jobs
In job scheduling, the concept of malleability has been explored since many
years ago. Research shows that malleability improves system performance, but
its utilization in HPC never became widespread. The causes are the difficulty
in developing malleable applications, and the lack of support and integration
of the different layers of the HPC software stack. However, in the last years,
malleability in job scheduling is becoming more critical because of the
increasing complexity of hardware and workloads. In this context, using nodes
in an exclusive mode is not always the most efficient solution as in
traditional HPC jobs, where applications were highly tuned for static
allocations, but offering zero flexibility to dynamic executions. This paper
proposes a new holistic, dynamic job scheduling policy, Slowdown Driven
(SD-Policy), which exploits the malleability of applications as the key
technology to reduce the average slowdown and response time of jobs. SD-Policy
is based on backfill and node sharing. It applies malleability to running jobs
to make room for jobs that will run with a reduced set of resources, only when
the estimated slowdown improves over the static approach. We implemented
SD-Policy in SLURM and evaluated it in a real production environment, and with
a simulator using workloads of up to 198K jobs. Results show better resource
utilization with the reduction of makespan, response time, slowdown, and energy
consumption, up to respectively 7%, 50%, 70%, and 6%, for the evaluated
workloads
Comparison of VerifyNow-P2Y12 test and Flow Cytometry for monitoring individual platelet response to clopidogrel. What is the cut-off value for identifying patients who are low responders to clopidogrel therapy?
<p>Abstract</p> <p>Background</p> <p>Dual anti-platelet therapy with aspirin and a thienopyridine (DAT) is used to prevent stent thrombosis after percutaneous coronary intervention (PCI). Low response to clopidogrel therapy (LR) occurs, but laboratory tests have a controversial role in the identification of this condition.</p> <p>Methods</p> <p>We studied LR in patients with stable angina undergoing elective PCI, all on DAT for at least 7 days, by comparing: 1) Flow cytometry (FC) to measure platelet membrane expression of P-selectin (CD62P) and PAC-1 binding following double stimulation with ADP and collagen type I either in the presence of prostaglandin (PG) E<sub>1</sub>; 2) VerifyNow-P2Y<sub>12 </sub>test, in which results are reported as absolute P2Y<sub>12</sub>-Reaction-Units (PRU) or % of inhibition (% inhibition).</p> <p>Results</p> <p>Thirty controls and 52 patients were analyzed. The median percentage of platelets exhibiting CD62P expression and PAC-1 binding by FC evaluation after stimulation in the presence of PG E<sub>1 </sub>was 25.4% (IQR: 21.4–33.1%) and 3.5% (1.7–9.4%), respectively. Only 6 patients receiving DAT (11.5%) had both values above the 1<sup>st </sup>quartile of controls, and were defined as LR. Evaluation of the same patients with the VerifyNow-P2Y<sub>12 </sub>test revealed that the area under the receiver-operating-characteristic (ROC) curve was 0.94 (95% CI: 0.84–0.98, p < 0.0001) for % inhibition and 0.85 (0.72–0.93, p < 0.005) for PRU. Cut-off values of ≤ 15% inhibition or > 213 PRU gave the maximum accuracy for the detection of patients defined as having LR by FC.</p> <p>Conclusion</p> <p>In conclusion our findings show that a cut-off value of ≤ 15% inhibition or > 213 PRU in the VerifyNow-P2Y<sub>12 </sub>test may provide the best accuracy for the identification of patients with LR.</p
Random, blocky and alternating ordering in supramolecular polymers of chemically bidisperse monomers
As a first step to understanding the role of molecular or chemical
polydispersity in self-assembly, we put forward a coarse-grained model that
describes the spontaneous formation of quasi-linear polymers in solutions
containing two self-assembling species. Our theoretical framework is based on a
two-component self-assembled Ising model in which the bidispersity is
parameterized in terms of the strengths of the binding free energies that
depend on the monomer species involved in the pairing interaction. Depending
upon the relative values of the binding free energies involved, different
morphologies of assemblies that include both components are formed, exhibiting
paramagnetic-, ferromagnetic- or anti ferromagnetic-like order,i.e., random,
blocky or alternating ordering of the two components in the assemblies.
Analyzing the model for the case of ferromagnetic ordering, which is of most
practical interest, we find that the transition from conditions of minimal
assembly to those characterized by strong polymerization can be described by a
critical concentration that depends on the concentration ratio of the two
species. Interestingly, the distribution of monomers in the assemblies is
different from that in the original distribution, i.e., the ratio of the
concentrations of the two components put into the system. The monomers with a
smaller binding free energy are more abundant in short assemblies and monomers
with a larger binding affinity are more abundant in longer assemblies. Under
certain conditions the two components congregate into separate supramolecular
polymeric species and in that sense phase separate. We find strong deviations
from the expected growth law for supramolecular polymers even for modest
amounts of a second component, provided it is chemically sufficiently distinct
from the main one.Comment: Submitted to Macromolecules, 6 figures. arXiv admin note: substantial
text overlap with arXiv:1111.176
De lo oculto que se les permite y de la visibilidad que se les niega: las mujeres en las letras y artes de Cartagena de Indias (1940-1949)
En el siguiente artĂculo nos proponemos abordar cĂłmo, a travĂ©s del cultivo de las letras y las artes, algunas mujeres de la Ă©lite cartagenera en la dĂ©cada del cuarenta, intentaron generar una crĂtica sobre su precaria condiciĂłn educativa – motivada por restricciones de gĂ©- nero–, al tiempo que buscaban ser visibles ante una sociedad que las excluĂa de lo pĂşblico y les atribuĂa roles nĂtidamente diferenciados del masculino. Para ello haremos un recorrido sobre los antecedentes histĂłricos y algunos debates presentados en la prensa sobre el papel de la mujer en relaciĂłn con las letras y las artes
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