scholarly journals Análisis de la vegetación arbórea en la provincia florística de Tehuacán-Cuicatlán

2017 ◽  
pp. 49
Author(s):  
Victor Jaramillo-Luque ◽  
Francisco González-Medrano
Keyword(s):  
Human Disturbance ◽  
Biotic Interactions ◽  
Principal Component ◽  
Vegetation Types ◽  
View Point ◽  
Reciprocal Averaging ◽  
Analysis Techniques ◽  
Classification Technique ◽  
Sierra Madre ◽  
Definition Of

The arboreal vegetation of a portion of the Tehuacán-Cuicatlán Valley is analyzed. An altitudinal gradient was followed along the leeward slopes of the Sierras de Juarez and Zongolica (Sierra Madre Oriental). Multivariate analysis techniques, ordination (principal component analysis and reciprocal averaging) and classification (informationanalysis program CENOSIS 2) were used. The results allow the definition of "groups" identifiable with vegetation types defined from a physiognomic-structural view point; however, the analysis performed shows that the arboreal vegetation of the study area possesses a variability and heterogeneity not detected by previous descriptive physiognomic studies. The importance of human disturbance and other factors (e.g. biotic interactions) affecting the structure and composition of the plant communities of the study area is discussed . The analysis techniques are compared with regards to their efficiency in handling high levels of vegetational heterogeneity , being the classification technique the most efficient one. Finally, some considerations judged interesting for future investigations are proposed.

scholarly journals Multi-objective parametrization of interatomic potentials for large deformation pathways and fracture of two-dimensional materials

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Xu Zhang ◽  
Hoang Nguyen ◽  
Jeffrey T. Paci ◽  
Subramanian K. R. S. Sankaranarayanan ◽  
Jose L. Mendoza-Cortes ◽  
...  
Keyword(s):  
Large Deformation ◽  
Functional Form ◽  
Principal Component ◽  
Interatomic Potentials ◽  
Two Dimensional ◽  
Multi Objective ◽  
Multi Objective Genetic Algorithm ◽  
Two Dimensional Materials ◽  
Definition Of

AbstractThis investigation presents a generally applicable framework for parameterizing interatomic potentials to accurately capture large deformation pathways. It incorporates a multi-objective genetic algorithm, training and screening property sets, and correlation and principal component analyses. The framework enables iterative definition of properties in the training and screening sets, guided by correlation relationships between properties, aiming to achieve optimal parametrizations for properties of interest. Specifically, the performance of increasingly complex potentials, Buckingham, Stillinger-Weber, Tersoff, and modified reactive empirical bond-order potentials are compared. Using MoSe2 as a case study, we demonstrate good reproducibility of training/screening properties and superior transferability. For MoSe2, the best performance is achieved using the Tersoff potential, which is ascribed to its apparent higher flexibility embedded in its functional form. These results should facilitate the selection and parametrization of interatomic potentials for exploring mechanical and phononic properties of a large library of two-dimensional and bulk materials.

Analisis Pembiayaan Dana Talangan Haji untuk  Biaya Perjalan Ibadah Haji

2018 ◽  
Vol 1 (2) ◽  
pp. 228-244
Author(s):  
Asmawarna Sinaga ◽  
Anjur Perkasa Alam ◽  
Fariz Arkan ◽  
Sri Wahyuni Hasibuan
Keyword(s):  
Islamic Law ◽  
Field Research ◽  
Interactive Methods ◽  
Islamic Banks ◽  
Data Presentation ◽  
Analysis Techniques ◽  
Collection Data ◽  
Definition Of ◽  
The Cost

  Analysis of the amount of financing the hajj bailout for the cost of the pilgrimage (Case Study of Bank Sumut Syariah Sub-Branch Stabat).Asmawarna Sinaga and Anjur Perkasa Alam. Hajj financing is a loan from a sharia bank to customers to cover the shortage of funds to obtain a seat (seat) Hajj at the time of repayment BPIH (Hajj Travel Expenses). This financing product uses the Qardh Wal Ijarah principle. The purpose of this research is to know the view of Islamic law against financing of Hajj bailout fund and to know the view of Islamic law about ujrah fee on akad of bailout fund of Hajj. This research is field research. The definition of the Hajj bailout is a bailout fund from a bank to a special customer to cover kekurangandana to cover the lack of funds to obtain a portion number at the time to pay the cost of organizing the pilgrimage. The research design uses a qualitative approach with non-statistical analysis While the data analysis techniques use content analysis and interactive methods consisting of data reduction, data collection, data presentation and conclusion. The results of this study note that the akad bailout funds in Islamic banks contain multi-akad, where the contract used qardh and ijarah is allowed. While the view of Islamic law regarding the taking of ujrah fee on hajj bailout fund is not in accordance with sharia due to the percentage of ujrah fee based on qardh fund.

Automated lung outline reconstruction in ventilation–perfusion scans using principal component analysis techniques

2003 ◽  
Vol 33 (2) ◽  
pp. 119-142 ◽  
Author(s):  
G. Serpen ◽  
R. Iyer ◽  
H.M. Elsamaloty ◽  
E.I. Parsai
Keyword(s):  
Principal Component Analysis ◽  
Principal Component ◽  
Component Analysis ◽  
Analysis Techniques

Identifying the main physical and socioeconomic drivers of illegal landfills in the Canary Islands

2018 ◽  
Vol 36 (11) ◽  
pp. 1049-1060 ◽  
Author(s):  
L Quesada-Ruiz ◽  
V Rodriguez-Galiano ◽  
R Jordá-Borrell
Keyword(s):  
Multivariable Analysis ◽  
Principal Component ◽  
Binary Logistic Regression ◽  
Gran Canaria ◽  
Analysis Techniques ◽  
La Palma ◽  
Socioeconomic Drivers ◽  
Geospatial Database ◽  
Total Data ◽  
Degree Of Association

The management of disposed waste in illegal landfills (ILs) is a significant problem in contemporary societies due to respective hazards for the environment and human health. This paper presents a characterisation of ILs on the islands of La Palma (LP) and Gran Canaria (GC) based on multivariable statistical analysis. Inspection of numerous sites on both islands revealed a total of 153 and 286 ILs on LP and GC, respectively. A geospatial database was created composed of different potentially explanatory features of different typology (177): waste type, control and vigilance, socioeconomic, accessibility, distance to elements of interest, visibility and physical. The degree of association between the explanatory features and the occurrence of ILs was analysed with the support of exploratory statistics and the multivariable analysis techniques of principal component analysis (PCA) and binary logistic regression (LR). PCA explained 82.34% and 81.83% of total data variance in LP and GC, respectively, considering 7 and 6 components (Kaiser–Mayer–Olkin; LP: 0.715; GC: 0.711). The LR models for LP and GC had an overall accuracy of 93.5% and 92.5%. In LP and GC, 6 of 23 features and 9 of 21 features were, respectively, selected. The features most associated with the occurrence of ILs were: in LP, building density, distance to agricultural spaces and distance to green zones; in GC, the industrial activity indicator, density of ground use transition to artificial covers, density of greenhouses and distance to communication routes.

scholarly journals A spectral theory for Wright’s inbreeding coefficients and related quantities

PLoS Genetics ◽  
2021 ◽  
Vol 17 (7) ◽  
pp. e1009665
Author(s):  
Olivier François ◽  
Clément Gain
Keyword(s):  
Population Structure ◽  
Genetic Variation ◽  
Population Genetic ◽  
Principal Component ◽  
Large Data ◽  
Population Subdivision ◽  
Adaptive Genetic Variation ◽  
Genomic Locus ◽  
Inbreeding Coefficients ◽  
Definition Of

Wright’s inbreeding coefficient, FST, is a fundamental measure in population genetics. Assuming a predefined population subdivision, this statistic is classically used to evaluate population structure at a given genomic locus. With large numbers of loci, unsupervised approaches such as principal component analysis (PCA) have, however, become prominent in recent analyses of population structure. In this study, we describe the relationships between Wright’s inbreeding coefficients and PCA for a model of K discrete populations. Our theory provides an equivalent definition of FST based on the decomposition of the genotype matrix into between and within-population matrices. The average value of Wright’s FST over all loci included in the genotype matrix can be obtained from the PCA of the between-population matrix. Assuming that a separation condition is fulfilled and for reasonably large data sets, this value of FST approximates the proportion of genetic variation explained by the first (K − 1) principal components accurately. The new definition of FST is useful for computing inbreeding coefficients from surrogate genotypes, for example, obtained after correction of experimental artifacts or after removing adaptive genetic variation associated with environmental variables. The relationships between inbreeding coefficients and the spectrum of the genotype matrix not only allow interpretations of PCA results in terms of population genetic concepts but extend those concepts to population genetic analyses accounting for temporal, geographical and environmental contexts.

A Lyapunov Theory-Based Neural Network Approach for Face Recognition

2010 ◽  
pp. 23-48 ◽  
Author(s):  
Li-Minn Ang ◽  
King Hann Lim ◽  
Kah Phooi Seng ◽  
Siew Wen Chin
Keyword(s):  
Neural Network ◽  
Face Recognition ◽  
Principal Component ◽  
Lyapunov Stability Theory ◽  
Recognition System ◽  
Lyapunov Theory ◽  
Neural Network Approach ◽  
Linear Discriminant ◽  
Feature Based ◽  
Definition Of

This chapter presents a new face recognition system comprising of feature extraction and the Lyapunov theory-based neural network. It first gives the definition of face recognition which can be broadly divided into (i) feature-based approaches, and (ii) holistic approaches. A general review of both approaches will be given in the chapter. Face features extraction techniques including Principal Component Analysis (PCA) and Fisher’s Linear Discriminant (FLD) are discussed. Multilayered neural network (MLNN) and Radial Basis Function neural network (RBF NN) will be reviewed. Two Lyapunov theory-based neural classifiers: (i) Lyapunov theory-based RBF NN, and (ii) Lyapunov theory-based MLNN classifiers are designed based on the Lyapunov stability theory. The design details will be discussed in the chapter. Experiments are performed on two benchmark databases, ORL and Yale. Comparisons with some of the existing conventional techniques are given. Simulation results have shown good performance for face recognition using the Lyapunov theory-based neural network systems.

Landscape Influences on Stream Habitats and Biological Assemblages

2006 ◽  
Keyword(s):  
Total Phosphorus ◽  
Human Disturbance ◽  
Regional Scale ◽  
Vertebrate Species ◽  
Catchment Scale ◽  
Human Disturbances ◽  
Disturbed Condition ◽  
Small Streams ◽  
Definition Of ◽  
Assemblage Metrics

<em>Abstract.</em>—At broad scales, the types and intensities of human disturbances to ecosystems vary along natural gradients. Biological assemblages also vary with natural and human disturbance gradients. We defined least-disturbed conditions for a set of water chemistry, catchment, and site-scale indicators of disturbance, for 835 Environmental Monitoring and Assessment Program sites in the Mountains, Xeric, and Plains regions of 12 conterminous western United States. For each disturbance indicator, the definition of least-disturbed was adjusted by the sites’ locations on the primary natural gradients. For example, the least-disturbed condition for phosphorus in eastern Plains streams allowed up to 100 µg/L total phosphorus, while in western Plains streams, less than 30 µg/L total phosphorus was required. Sites were scored by the number of times they met the least-disturbed condition for all disturbance indicators. We also applied this process to score for most-disturbed condition. The importance of disturbance types varied regionally and along natural gradients. For example, catchment-scale disturbance measures did not distinguish between least- and most-disturbed sites for small streams at higher elevations, but were important for larger streams and at lower elevations. We examined regional-scale patterns in aquatic vertebrate species and assemblage metrics, and macrobenthos assemblage metrics at least- and most-disturbed sites. Most-disturbed sites in the Mountains and Xeric regions had higher proportions of nonnative and tolerant vertebrates and noninsect macrobenthos, and lower proportions of Ephemeroptera, Plecoptera, and Trichoptera individuals and taxa than did the least-disturbed sites. The Plains region has been extensively used by humans and showed less contrast between disturbance classes for most of these measures.

scholarly journals Process of forming a regional recreation system in the conditions of a border region

2020 ◽  
Vol 164 ◽  
pp. 07028
Author(s):  
Anastasia Vasilieva ◽  
Raisa Belaya
Keyword(s):  
Regional Policy ◽  
Principal Component ◽  
Environmental Safety ◽  
The United States ◽  
Climatic Conditions ◽  
Border Region ◽  
Significant Heterogeneity ◽  
Factor Rotation ◽  
The Face ◽  
Definition Of

Significant heterogeneity of the level of development of the Russian border, including in the field of recreation, imposes requirements for differentiation in the regional policy. Definition of the types of territories helps to solve applied management tasks more effectively. In this context, the factors by which these types were formed are important. To solve this problem, the authors conducted a factor analysis through the principal component method using oblique factor rotation. Three blocks of variables were analyzed that characterize the subjects of the Russian Federation that have land borders on the mainland (including river and lake borders) and sea borders with neighboring countries located on the map clockwise from Norway to the United States (border regions of Russia) for the period from 2010 to 2018. As a result, five factors were identified: the factor of the demand for the services of the recreational system, the factor of the development of the infrastructure of the recreational system in climatic conditions, the environmental safety factor, the factor of investment in the development of the recreational system infrastructure, the factor of the location at the border. The results of the study can be used as a practical tool for developing recommendations in the field of regional policy aimed at development of a recreational system, taking into account the factors determined for each identified group. The results of the study were obtained in the framework of the state task of the IE KarRC RAS on the topic “Institutions and social inequality in the face of global challenges and regional restrictions”.

scholarly journals The Definition of Entropy for Quantum Unstable Systems: A View-Point Based on the Properties of Gamow States

Entropy ◽  
2018 ◽  
Vol 20 (4) ◽  
pp. 231 ◽  
Author(s):  
Osvaldo Civitarese ◽  
Manuel Gadella
Keyword(s):  
View Point ◽  
Unstable Systems ◽  
Gamow States ◽  
Definition Of

Summarizing Opinions with Sentiment Analysis from Multiple Reviews on Travel Destinations

2018 ◽  
Vol 9 (2) ◽  
pp. 111-120
Author(s):  
Argha Roy ◽  
Shyamali Guria ◽  
Suman Halder ◽  
Sayani Banerjee ◽  
Sourav Mandal
Keyword(s):  
Social Media ◽  
Sentiment Analysis ◽  
Efficient Method ◽  
Text Analysis ◽  
Human Life ◽  
Analysis Techniques ◽  
Classification Technique ◽  
Textual Data ◽  
The Web

Recently, the web has been crowded with growing volumes of various texts on every aspect of human life. It is difficult to rapidly access, analyze, and compose important decisions using efficient methods for raw textual data in the form of social media, blogs, feedback, reviews, etc., which receive textual inputs directly. It proposes an efficient method for summarization of various reviews of tourists on a specific tourist spot towards analyzing their sentiments towards the place. A classification technique automatically arranges documents into predefined categories and a summarization algorithm produces the exact condensed input such that output is most significant concepts of source documents. Finally, sentiment analysis is done in summarized opinion using NLP and text analysis techniques to show overall sentiment about the spot. Therefore, interested tourists can plan to visit the place do not go through all the reviews, rather they go through summarized documents with the overall sentiment about target place.

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