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On the comparison of different Kernel functionals and neighborhood geometry for Nonlocal Means filtering

JOSE ISMAEL DE LA ROSA VARGAS José de Jesús Villa Hernández (2018)

The present work proposes a review and comparison of different Kernel functionals and neighborhood geometry for Nonlocal Means (NLM) in the task of digital image filtering. Some different alternatives to change the classical exponential kernel function used

in NLM methods are explored. Moreover, some approaches that change the geometry of the neighborhood and use dimensionality reduction of the neighborhood or patches onto principal component analysis (PCA) are also analyzed, and their performance is compared with respect to the classic NLM method. Mainly, six approaches were compared using quantitative and qualitative evaluations, to do this an homogeneous framework has been established using the same simulation platform, the same computer, and same conditions for the initializing parameters.

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Article

INGENIERÍA Y TECNOLOGÍA Image filtering Nonlocal means Kernel functionals Sparse learning techniques Collaborative filtering

Fringe pattern denoising using spatial oriented gaussian filters

JOSE ISMAEL DE LA ROSA VARGAS José de Jesús Villa Hernández (2020)

In this paper, it is proposed a gaussian convolution-based fringe pattern denoising method. As will be shown, this method is robust enough compared with some of the most outstanding methods in the literature. Additionally, the proposed method overcomes the problem of underperformance in low-frequency fringes that is common in most oriented filtering methods, while keeping the great advantages of convolution-based filters. The advantages of the proposed denoising method will be demonstrated with experiments realized over synthetic and real fringe patterns, and comparing the performance with four representative methods, already reported.

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Article

INGENIERÍA Y TECNOLOGÍA Fringe images Filtering Gaussian filters

FPGA-based educational platform for real-time image processing experiments

JUAN MANUEL RAMIREZ CORTES MARIA DEL PILAR GOMEZ GIL VICENTE ALARCON AQUINO Jorge Martinez_Carballido EMMANUEL MORALES FLORES (2010)

In this paper, an implementation of an educational platform for real-time linear and morphological image filtering using a FPGA NexysII, Xilinx®, Spartan 3E, is described. The system is connected to a USB port of a personal computer, which in that way form a powerful and low-cost design station for educational purposes. The FPGA-based system is accessed through a MATLAB graphical user interface, which handles the communication setup and data transfer. The system allows the students to perform comparisons between results obtained from MATLAB simulations and FPGA-based real-time processing. Concluding remarks derived from course evaluations and lab reports are presented.

Article

Image Processing Hardware Education Filtering CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA ELECTRÓNICA

Qualitative, comparative, and collaborative research at large scale: an introduction to GENNOVATE

Lone Badstue (2018)

What is the relationship between gender norms, agency, and agricultural innovation? How might we undertake and what can we learn from a comparative approach to this question? GENNOVATE—a comparative and collaborative research project—addresses these questions using contextually embedded qualitative analyses that also allow for comparison and extrapolation of patterns across multiple locations. This paper provides an overview of the conceptual approach and the methodological strategy that informed GENNOVATE's twin objectives and research design. The conceptual framework underlying this original research initiative is introduced and the challenges and opportunities faced when combining inductive and deductive analytic approaches are discussed. The empirical and methodological issues are explored and the broad relevance of GENNOVATE’s research approach beyond the field of agricultural development is reflected upon.

Article

Gender analysis Gender training Agricultural innovation systems Gender Norms Agency Social Embeddedness Qualitative Comparative Research Collaborative Research GENDER INNOVATION QUALITATIVE ANALYSIS CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Our turn. An evaluation of the turn to the practice based approach in information science

GIBRAN RIVERA GONZALEZ (2013)

"The paper evaluates the turn to practice in information science, through a summary of the theory and exploration of empirical data about the use of collaborative software. Themes of practice theory, namely: change, socio- materiality, relational thinking and knowing are summarised and previous use of practice based approaches to studying the adoption of information technologies are discussed. The empirical data is thirty interviews with Human Resource professionals involved in a project in a large Mexican University. The strength of the analysis using the practice based approach is to dee- pen our understanding of context emerge from an analysis of the data. The sociology of translation can be used to further deepen understanding of the political process around the project. Remaining issues point to a major issue with practice based approaches, namely the adequacy of its treatment of structural power."

Book part

CIENCIAS SOCIALES Practice theory Collaborative software Adoption Information technologies

Prediction of multiple-trait and multiple-environment genomic data using recommender systems

Osval Antonio Montesinos-Lopez Jose Crossa David Mota-Sanchez Ravi Gopal Singh Suchismita Mondal Philomin Juliana (2018)

In genomic-enabled prediction, the task of improving the accuracy of the prediction of lines in environments is difficult because the available information is generally sparse and usually has low correlations between traits. In current genomic selection, although researchers have a large amount of information and appropriate statistical models to process it, there is still limited computing efficiency to do so. Although some statistical models are usually mathematically elegant, many of them are also computationally inefficient, and they are impractical for many traits, lines, environments, and years because they need to sample from huge normal multivariate distributions. For these reasons, this study explores two recommender systems: itembased collaborative filtering (IBCF) and the matrix factorization algorithm (MF) in the context of multiple traits and multiple environments. The IBCF and MF methods were compared with two conventional methods on simulated and real data. Results of the simulated and real data sets show that the IBCF technique was slightly better in terms of prediction accuracy than the two conventional methods and the MF method when the correlation was moderately high. The IBCF technique is very attractive because it produces good predictions when there is high correlation between items (environment–trait combinations) and its implementation is computationally feasible, which can be useful for plant breeders who deal with very large data sets.

Article

Genomics Genotype environment interaction Statistical methods Precision agriculture Genomic Information Matrix Factorization Prediction Accuracy Collaborative Foltering GenPred Shared Data Resources GENOMICS GENOTYPE ENVIRONMENT INTERACTION STATISTICAL METHODS CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Integrated three-dimensional reconstruction with efficiently acquiring reflectance fields

MARIA LUISA ROSAS CHOLULA (2013)

The reconstruction of object surfaces is an important area in computer vision. This

area is directed towards the recovery of three-dimensional information of an object

placed in a scene. Most classical existing reconstruction methods assume that objects

in the scene reflect light equally in all directions. This assumption on surface

reflectance is referred as a Lambertian BRDF (Bidirectional Reflectance Distribution

Function) however, Lambertian reflectance is not fulfilled for real-world objects, leading

to incorrect depth estimates. Several methods propose a partial solution taking

advantage of calibrated cameras and lights or some approximation of the surface

reflectance.

Reflectance fields are a common image-based model used for rendering the appearance

of objects with a high-degree of realism. Reflectance fields are used in a

variety of applications. For example, they are used to capture the appearance of

real-world objects with complex geometry, like human bodies, furry teddy bears, or

bonsai trees. They are also used to represent intricate distributions of light, like the

illumination from a flash light. However, despite the increasing popularity of using

reflectance fields, fast methods do not exist for acquiring them.

This thesis presents two main contributions towards reflectance field acquisition

and three-dimensional reconstruction. The first is a method for acquiring efficiently

the reflectance field data to provide the surface reflectance information. This method

introduces the use of independent component analysis, it enables fast acquisition of

the reflectance field. The prototype acquisition system consists of a pair of projector

and camera controlled by a computer. The effectiveness of the system is demonstrated

with scenes composed of different material properties where the reflectance quality is

maintained.

The second contribution is a three-dimensional reconstruction of real-world objects

placed in the scene. Three-dimensional reconstruction is obtained by relating depth

estimations with reflectance fields. The reflectance field is integrated with threedimensional

reconstruction equations by considering the system setup as a stereo

system, it provides depth estimations of objects exhibiting different material properties

with high accuracy.

Doctoral thesis

Electroencephalography Frequency-domain analysis Correlation methods Filtering theory CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS CIENCIA DE LOS ORDENADORES

Comparative Analysis of directional filtering techniques in fringe patterns

JOSE ISMAEL DE LA ROSA VARGAS Ma. Auxiliadora Araiza Esquivel José de Jesús Villa Hernández (2011)

Se presenta una comparación de las técnicas: Filtros de regularización (RQCF), Filtrado espacial con máscaras orientables (OSFM), Ecuaciones parciales de segundo orden orientables (SOPDE) y Filtros direccionales (DF). Uno de los objetivos de este documento es realizar una comparación y evaluar el desempeño de estas técnicas para diferentes tipos y niveles de ruido utilizando imágenes de franjas sintéticas.

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Conference paper

INGENIERÍA Y TECNOLOGÍA Image filtering directional transforms

Stories that supply us for life: literature and therapy

DORA ADOLFINA AYORA TALAVERA (2016)

This writing is a poetical invitation to read novels, as a good way to become a better therapist. In it, I introduce some learnings that in my practice -as a therapist -have been connected with my hobby: read novels. Reading them you can gain alternative, original and creative stories that can enrich your practice. Through writing I introduce some novels and its teaching.

Article

HUMANIDADES Y CIENCIAS DE LA CONDUCTA Literature Therapy Novels Fiction Collaborative approach

A practice-based approach to understanding participation in online communities

GIBRAN RIVERA GONZALEZ (2016)

"The take up of online communities in organisations is often patchy. Previous studies, mainly within

the cognitive tradition of thinking, explain such non-participation either through features of technology

or through individuals’ motivational structures, and look at participation as a static, individualistic

and functionalistic phenomenon.Theaimof this article is to explore the insights on participation

from a practice-based approach (PBA).The paper draws upon empirical data from the use of collaborative

technology in a Mexican University. The adoption of community technology is shown to be

shaped by dynamic, collective, historical and contextual forces. Based on these findings, the val"

17-32

Article

10.1111/jcc4.12148

CIENCIAS SOCIALES Practice-Based Approach Participation in Online Communities Collaborative Technology Human Resource Practice