Steel Bars Identification in Reinforced Concrete Structures by Using ANN And Magnetic Fields

Abstract This work proposes a methodology for non destructive testing (NDT) of reinforced concrete structures, using superficial magnetic fields and artificial neural networks, in order to identify the size and position of steel bars, embedded into the concrete. For the purposes of this paper, magnetic induction curves were obtained by using a finite element program. Perceptron Multilayered (PML) ANNs, with Levemberg-Marquardt training algorithm were used. The results presented very good agreement with the expect ones, encouraging the development of real systems based upon the proposed methodology

Enhancing the quality of international orthopedic medical mission trips using the blue distinction criteria for knee and hip replacement centers

Background: Several organizations seek to address the growing burden of arthritis in developing countries by providing total joint replacements (TJR) to patients with advanced arthritis who otherwise would not have access to these procedures. Because these mission trips operate in resource poor environments, some of the features typically associated with high quality care may be difficult to implement. In the U.S., many hospitals that perform TJRs use the Blue Cross/Shield’s Blue Distinction criteria as benchmarks of high quality care. Although these criteria were designed for use in the U.S., we applied them to Operation Walk (Op-Walk) Boston’s medical mission trip to the Dominican Republic. Evaluating the program using these criteria illustrated that the program provides high quality care and, more importantly, helped the program to find areas of improvement. Methods: We used the Blue Distinction criteria to determine if Op-Walk Boston achieves Blue Distinction. Each criterion was grouped according to the four categories included in the Blue Distinction criteria— “general and administrative”, “structure”, “process”, or “outcomes and volume”. Full points were given for criteria that the program replicates entirely and zero points were given for criteria that are not replicated entirely. Of the non-replicated criteria, Op-Walk Boston’s clinical and administrative teams were asked if they compensate for failure to meet the criterion, and they were also asked to identify barriers that prevent them from meeting the criterion. Results: Out of 100 possible points, the program received 71, exceeding the 60-point threshold needed to qualify as a Blue Distinction center. The program met five out of eight “required” criteria and 11 out of 19 “informational” criteria. It scored 14/27 in the “general” category, 30/36 in the “structure” category, 17/20 in the “process” category, and 10/17 in the “outcomes and volume” category. Conclusion: Op-Walk Boston qualified for Blue Distinction. Our analysis highlights areas of programmatic improvement and identifies targets for future quality improvement initiatives. Additionally, we note that many criteria can only be met by hospitals operating in the U.S. Future work should therefore focus on creating criteria that are applicable to TJR mission trips in the context of developing countries

Identity of the universal repulsive-core singularity with Yang-Lee edge criticality

Lattice and continuum fluid models with repulsive-core interactions typically display a dominant, critical-type singularity on the real, negative activity axis. Lai and Fisher recently suggested, mainly on numerical grounds, that this repulsive-core singularity is universal and in the same class as the Yang-Lee edge singularities, which arise above criticality at complex activities with positive real part. A general analytic demonstration of this identification is presented here using a field-theory approach with separate representation of the repulsive and attractive parts of the pair interactions.Comment: 6 pages, 3 figure

Exposing errors related to weak memory in GPU applications

© 2016 ACM.We present the systematic design of a testing environment that uses stressing and fuzzing to reveal errors in GPU applications that arise due to weak memory effects. We evaluate our approach on seven GPUS spanning three NVIDIA architectures, across ten CUDA applications that use fine-grained concurrency. Our results show that applications that rarely or never exhibit errors related to weak memory when executed natively can readily exhibit these errors when executed in our testing environment. Our testing environment also provides a means to help identify the root causes of such errors, and automatically suggests how to insert fences that harden an application against weak memory bugs. To understand the cost of GPU fences, we benchmark applications with fences provided by the hardening strategy as well as a more conservative, sound fencing strategy

Participation in physical activity in patients 1–4 years post total joint replacement in the Dominican Republic

Background: To address both the growing burden of joint disease and the gaps in medical access in developing nations, medical relief organizations have begun to launch programs to perform total joint replacement (TJR) on resident populations in developing countries. One outcome of TJR of particular interest is physical activity (PA) since it is strongly linked to general health. This study evaluates the amount of postoperative participation in PA in low-income patients who received total joint replacement in the Dominican Republic and identifies preoperative predictors of postoperative PA level. Methods: We used the Yale Physical Activity Survey (YPAS) to assess participation in postoperative PA 1–4 years following total knee or hip replacement. We compared the amount of aerobic PA reported by postoperative TJR patients with the levels of PA recommended by the CDC and WHO. We also analyzed preoperative determinants of postoperative participation in aerobic PA in bivariate and multivariate analyses. Results: 64 patients out of 170 eligible subjects (52/128 TKR and 14/42 THR) who received TJR between 2009–2012 returned for an annual follow-up visit in 2013, with a mean treatment-to-follow-up time of 2.1 years. 43.3% of respondents met CDC/WHO criteria for sufficient participation in aerobic PA. Multivariate analyses including data from 56 individuals identified that patients who were both younger than 65 and at least two years postoperative had an adjusted mean activity dimensions summary index (ADSI) 22.9 points higher than patients who were 65 or older and one year postoperative. Patients who lived with friends or family had adjusted mean ADSI 17.2 points higher than patients living alone. Patients who had the most optimistic preoperative expectations of outcome had adjusted mean ADSI scores that were 19.8 points higher than those who were less optimistic. Conclusion: The TJR patients in the Dominican cohort participate in less PA than recommended by the CDC/WHO. Additionally, several associations were identified that potentially affect PA in this population; specifically, participants who are older than 65, recently postoperative, less optimistic about postoperative outcomes and who live alone participate in less PA

On the Phase Structure of the 3D Edwards Anderson Spin Glass

We characterize numerically the properties of the phase transition of the three dimensional Ising spin glass with Gaussian couplings and of the low temperature phase. We compute critical exponents on large lattices. We study in detail the overlap probability distribution and the equilibrium overlap-overlap correlation functions. We find a clear agreement with off-equilibrium results from previous work. These results strongly support the existence of a continuous spontaneous replica symmetry breaking in three dimensional spin glasses.Comment: 30 pages and 17 figures. Final version to be published in PR

Intermediate temperature dynamics of one-dimensional Heisenberg antiferromagnets

We present a general theory for the intermediate temperature (T) properties of Heisenberg antiferromagnets of spin-S ions on p-leg ladders, valid for 2Sp even or odd. Following an earlier proposal for 2Sp even (Damle and Sachdev, cond-mat/9711014), we argue that an integrable, classical, continuum model of a fixed-length, 3-vector applies over an intermediate temperature range; this range becomes very wide for moderate and large values of 2Sp. The coupling constants of the effective model are known exactly in terms of the energy gap above the ground state (for 2Sp even) or a crossover scale (for 2Sp odd). Analytic and numeric results for dynamic and transport properties are obtained, including some exact results for the spin-wave damping. Numerous quantitative predictions for neutron scattering and NMR experiments are made. A general discussion on the nature of T>0 transport in integrable systems is also presented: an exact solution of a toy model proves that diffusion can exist in integrable systems, provided proper care is taken in approaching the thermodynamic limit.Comment: 38 pages, including 12 figure

Random Resistor-Diode Networks and the Crossover from Isotropic to Directed Percolation

By employing the methods of renormalized field theory we show that the percolation behavior of random resistor-diode networks near the multicritical line belongs to the universality class of isotropic percolation. We construct a mesoscopic model from the general epidemic process by including a relevant isotropy-breaking perturbation. We present a two-loop calculation of the crossover exponent $\phi$. Upon blending the $\epsilon$-expansion result with the exact value $\phi =1$ for one dimension by a rational approximation, we obtain for two dimensions $\phi = 1.29\pm 0.05$. This value is in agreement with the recent simulations of a two-dimensional random diode network by Inui, Kakuno, Tretyakov, Komatsu, and Kameoka, who found an order parameter exponent $\beta$ different from those of isotropic and directed percolation. Furthermore, we reconsider the theory of the full crossover from isotropic to directed percolation by Frey, T\"{a}uber, and Schwabl and clear up some minor shortcomings.Comment: 24 pages, 2 figure

Efecto del uso del lodo generado en el tratamiento de las aguas negras en la acumulación de Fe, Mn, Ni, Zn, Cu e Cr en suelos brasileños.

Entre las distintas posibilidades de uso del lodo generado en el tratamienteo de las aguas negras, aquella destinada a la agricultura es una de las mas aceptables, pues, este material es sumamente rico en sustancias orgánicas y minerales. Con esta característica el lodo podrá ser utiizado para condicionar el suelo y/o como adobo