1,720,999 research outputs found
Paviršių trūkių identifikavimas, paremtas vaizdų analize ir giliojo mokymosi metodais.
No full textConcrete cracks pose a significant challenge to the stability of structures, and in some cases, repairs may be costly or even necessitate complete rebuilding to prevent building collapse. However, detecting and repairing damage in a timely manner can prevent many accidents. Unfortunately, detecting cracks can be difficult, particularly in hard-to-reach areas or dangerous locations. Nuclear power plants, subsea pipelines, and dams, among other facilities, require regular external and internal structural checks, which can be expensive and challenging. Recently, machine learning based approaches have been proposed for asset integrity inspections using UAV. This paper explores the use of machine learning models to detect concrete cracks, which could simplify the process and reduce the cost of regular check-ups. However, we observed that in some cases machine learning models underperforms or can be deceived by poor quality data or data with significant displacement. In this research work, we propose image enhancement techniques to improve model predictions. We believe that our proposed mathematical and machine learning algorithms will make crack detection easier, safer, and more cost-effective for regular check-ups
Baigtinių skirtumų, baigtinių tūrių bei dirbtinių neuroninių tinklų metodų palyginimas sprendžiant tiesioginį uždavinį.
No full textThis thesis focuses on a problem of determining field distribution of a particular measure u throughout a highly heterogeneous and layered permeability domain assuming some driving function. An elliptic Partial Differential Equation, used to describe such distribution at an equilibrium state, is called Poisson's Equation which originates from Darcy's Law. The aforementioned equation describes diffusion and has no temporal dimension, thus requiring sufficient boundary conditions to be uniquely solved using numerical methods. After performing a comparison study of two such methods known as Finite Difference Method (FDM) and Finite Volume Method (FVM), a proposition of an alternative approach of using Artificial Neural Network (ANN) to solve a given problem was made. The ANN is referred to as a Coordinate Discretized Neural Network (CDNN) throughout the thesis. Both numerical methods were implemented on a two-dimensional grid and compared with each other on highly heterogeneous and layered permeability domains. Since FVM is is both locally and globally conservative method it outperformed FDM in several ways. The latter created non-monotonous solutions with sharp transitions in between the sub-domains and overall drew unrealistic maps of u that were excessively impacted by the underlying permeability domain. Conclusions were drawn from these observations to train CDNN solely on FVM's generated data, keeping in mind how a proper method should behave. CDNN produced accurate results, managing to replicate the FVM, even on some complex permeability distributions. However, high noise contamination present in the results leaves room for further network architecture improvement and there might be even possibilities to reformulate the modelling approach to improve the results. Suggestions for further development and possible network enhancements, were discussed in greater detail in the concluding discussion chapter
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Numerical convergence of the family of flux-continuous schemes with variable quadrature ( , ) for single phase flow in porous media /
No full textFinite-volume schemes, which honor pressure and flux-continuity conditions, is developed using double quadrature , referred as double family scheme. The scheme is applicable to solve the elliptic pressure equation used in reservoir simulation. Schemes are applicable on both regular cartesian and unstructured triangular meshes. The scheme is defined over a control-volume distributed formulation. The scheme can be applied to both diagonal and full permeability tensor elliptic pressure equation with discontinuous coefficients. The scheme removes the first order errors, which are introduced by standard reservoir simulation schemes when applied to full tensor flow. The scheme is quantified with help of a quadrature rule. When the scheme is applied to highly heterogeneous and anisotropic porous media it does not honor maximum principle resulting in unstable solution with oscillatory behavior. The numerical solution is termed non-monotonicity for high anisotropy ratios with results showing oscillations in the numerical pressure solution. In this paper a double quadrature flux continuous schemes is presented, which with specific choice of quadrature helps in improved stability of the numerical solutions. Numerical convergence of the scheme is also demonstrated with help of a number of numerical test cases and schemes impact on monotonicity behavior is also demonstrated with numerical examples
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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