Articles de revues : « First order indices »

1

Sakhnovich, L. A. « The deficiency indices of a system of first-order differential equations ». Siberian Mathematical Journal 38, n^o 6 (décembre 1997) : 1182–83. http://dx.doi.org/10.1007/bf02675944.

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Saint-Geours, N., S. Tarantola, V. Kopustinskas et R. Bolado-Lavin. « Computing first-order sensitivity indices with contribution to the sample mean plot ». Journal of Statistical Computation and Simulation 85, n^o 7 (27 juin 2014) : 1334–57. http://dx.doi.org/10.1080/00949655.2014.932358.

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Tarantola, Stefano, et Masato Koda. « Improving Random Balance Designs For The Estimation Of First Order Sensitivity Indices ». Procedia - Social and Behavioral Sciences 2, n^o 6 (2010) : 7753–54. http://dx.doi.org/10.1016/j.sbspro.2010.05.212.

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Tarantola, S., D. Gatelli et T. A. Mara. « Random balance designs for the estimation of first order global sensitivity indices ». Reliability Engineering & ; System Safety 91, n^o 6 (juin 2006) : 717–27. http://dx.doi.org/10.1016/j.ress.2005.06.003.

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Yan, Yong Hong, et Bruce Felmingham. « First and second order instability of the Shanghai and Shenzhen share price indices ». Applied Economics Letters 13, n^o 9 (15 juillet 2006) : 605–8. http://dx.doi.org/10.1080/13504850500424918.

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Rasheed, Razia, et Abdul Ahad Buhroo. « Updated checklist and diversity of predatory insect fauna with one first report from Kashmir, India ». Polish Journal of Entomology 89, n^o 3 - Ahead of print (30 septembre 2020) : 142–52. http://dx.doi.org/10.5604/01.3001.0014.4008.

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The diversity of predatory insect fauna in nine districts of Kashmir was assessed. Collection was done in agroecosystem with the help of different collecting nets and handpicking methods. As a result of two-year study, a total of 50 species belonging to 14 families and 7 orders were identified. Hierodula patellifera Serville, 1839 of the order Mantodea was reported for the first time from the Kashmir valley. Also, different diversity indices used during the present study revealed the existence of considerable number of predatory species distributed evenly throughout the study area. Diversity of different study sites was correlated by Hutcheson’s t- test. Highest values of diversity indices were observed in the order Coleoptera.

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Kupchik, Eugene J. « Structure-Molar Refraction Relationships of Alkylsilanes Using Empirically-Modified First Order Molecular Connectivity Indices ». Quantitative Structure-Activity Relationships 5, n^o 3 (1986) : 95–98. http://dx.doi.org/10.1002/qsar.19860050304.

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Permanyer, Iñaki, et M. Azhar Hussain. « First Order Dominance Techniques and Multidimensional Poverty Indices : An Empirical Comparison of Different Approaches ». Social Indicators Research 137, n^o 3 (26 avril 2017) : 867–93. http://dx.doi.org/10.1007/s11205-017-1637-x.

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Krüger, Frank, Antje Nuthmann et Elke van der Meer. « Pupillometric indices of temporal order representation in semantic memory ». Zeitschrift für Psychologie / Journal of Psychology 209, n^o 4 (octobre 2001) : 402–15. http://dx.doi.org/10.1026//0044-3409.209.4.402.

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Summary. The present study used the technique of pupillometry to study whether pupillary changes are sensitive to variations in the processing of temporal order information in semantic memory. By employing two recognition tasks the temporal orientation (chronological vs. reverse) between pre-information and target was manipulated. The first experiment examined frequently occurring sequences of everyday events (e.g., cut - bleed - bandage) with the same strength of temporal relatedness for preceding and succeeding events. The second experiment investigated event-feature pairs (e.g., melt, solid - fluid) with temporal connectives (before, after). In addition to the psychological indicators reaction times and error rates two further psychophysiological indicators - maximum pupil diameters and dilatation times - were raised to validate the behavioral data. The results show that time’s arrow is not restricted to sequences of events, but also embedded in the mental representation of individual events. In both experiments psychophysiological indicators coincide with the psychological indicators. The pupillometric results provide additional new information: They indicate that the processing of temporal orientation towards future time does not only consume less time and produces less errors, but also that the processing is making less demands on mental resources. The presented study demonstrates that task-evoked pupillary response is a reliable and sensitive indicator for the experimental study of cognitive load.

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Wang, Wenxuan, Hangshan Gao, Pengfei Wei et Changcong Zhou. « Extending first-passage method to reliability sensitivity analysis of motion mechanisms ». Proceedings of the Institution of Mechanical Engineers, Part O : Journal of Risk and Reliability 231, n^o 5 (10 juillet 2017) : 573–86. http://dx.doi.org/10.1177/1748006x17717614.

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Identifying the parameters that substantially affect the time-dependent reliability is critical for reliability-based design of motion mechanism. The time-dependent local reliability sensitivity and global reliability sensitivity are the two effective techniques for this type of analysis. This work extends the first-passage method and PHI2 method, which are commonly used for estimating the time-dependent reliability, for efficiently estimating the time-dependent local reliability sensitivity and global reliability sensitivity indices of the motion mechanism. Both the local reliability sensitivity and global reliability sensitivity indices are analytically derived based on the Poisson assumption–based first-passage method and the first-order Taylor’s expansion of the motion error function. Compared with the current envelope function method for estimating the time-dependent local reliability sensitivity and global reliability sensitivity indices, the developed method does not need to estimate the second-order derivatives of motion error function, thus is more applicable. The accuracy and effectiveness of the proposed method are demonstrated by a numerical example and a satellite antenna, the direction of which is controlled by a four-bar function generator mechanism.

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Gu, Lili, Shamaila Yousaf, Akhlaq Ahmad Bhatti, Peng Xu et Adnan Aslam. « Computing Some Degree-Based Topological Indices of Honeycomb Networks ». Complexity 2022 (4 janvier 2022) : 1–13. http://dx.doi.org/10.1155/2022/2771059.

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A topological index is a numeric quantity related with the chemical composition claiming to correlate the chemical structure with different chemical properties. Topological indices serve to predict physicochemical properties of chemical substance. Among different topological indices, degree-based topological indices would be helpful in investigating the anti-inflammatory activities of certain chemical networks. In the current study, we determine the neighborhood second Zagreb index and the first extended first-order connectivity index for oxide network O X n , silicate network S L n , chain silicate network C S n , and hexagonal network H X n . Also, we determine the neighborhood second Zagreb index and the first extended first-order connectivity index for honeycomb network H C n .

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Ruiz, Carlos Alexis Gómez, et Florian Luca. « On the zero–multiplicity of a fifth-order linear recurrence ». International Journal of Number Theory 15, n^o 03 (21 mars 2019) : 585–95. http://dx.doi.org/10.1142/s1793042119500301.

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We consider a family of linear recurrence sequences [Formula: see text] of order [Formula: see text] whose first [Formula: see text] terms are [Formula: see text] and each term afterwards is the sum of the preceding [Formula: see text] terms. In this paper, we study the zero–multiplicity on [Formula: see text] when the indices are extended to all integers. In particular, we give a upper bound (dependent on [Formula: see text]) for the largest positive integer [Formula: see text] such that [Formula: see text] and show that [Formula: see text] has zero–multiplicity unitary when the indices are extended to all the integers.

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Tissot, J. Y., et C. Prieur. « A randomized orthogonal array-based procedure for the estimation of first- and second-order Sobol' indices ». Journal of Statistical Computation and Simulation 85, n^o 7 (28 octobre 2014) : 1358–81. http://dx.doi.org/10.1080/00949655.2014.971799.

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Dahame, Tahar, Bachir Bentria, Houda Faraoun, Ali Benghia et A. H. Reshak. « Electronic structure, first and second order physical properties of MPS4 : a theoretical study ». Materials Science-Poland 34, n^o 2 (1 juin 2016) : 275–85. http://dx.doi.org/10.1515/msp-2016-0060.

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AbstractWe have calculated the electronic structure and physical properties of metal thiophosphate compounds InPS4 and AlPS 4by means of pseudopotential density functional theory (DFT) coupled with the modern theory of polarization. The targeted physical properties are ﬁrst and second order optical properties as well as elastic, piezoelectric and electro-optic coefﬁcients. Furthermore, population analysis is presented in order to evaluate the covalent-ionic character of the constituent bonds. The calculated elastic constants, refractive indices and second order optical coefﬁcients of InPS4 are in good agreement with experimental values. With the absence of any theoretical or experimental physical properties of AlPS4, we predict that this compound has high piezoelectric coefﬁcients with d14 = − 73.82 pm/V, d25 = − 10.96 pm/V and d36 = 28.19 pm/V.

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De La Cal, Jesús, et Javier Cárcamo. « Inverse Stochastic Dominance, Majorization, and Mean Order Statistics ». Journal of Applied Probability 47, n^o 1 (mars 2010) : 277–92. http://dx.doi.org/10.1239/jap/1269610831.

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The inverse stochastic dominance of degree r is a stochastic order of interest in several branches of economics. We discuss it in depth, the central point being the characterization in terms of the weak r-majorization of the vectors of expected order statistics. The weak r-majorization (a notion introduced in the paper) is a natural extension of the classical (reverse) weak majorization of Hardy, Littlewood and Pòlya. This work also shows the equivalence between the continuous majorization (of higher order) and the discrete r-majorization. In particular, our results make it clear that the cases r = 1, 2 differ substantially from those with r ≥ 3, a fact observed earlier by Muliere and Scarsini (1989), among other authors. Motivated by this fact, we introduce new stochastic orderings, as well as new social inequality indices to compare the distribution of the wealth in two populations, which could be considered as natural extensions of the first two dominance rules and the S-Gini indices, respectively.

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De La Cal, Jesús, et Javier Cárcamo. « Inverse Stochastic Dominance, Majorization, and Mean Order Statistics ». Journal of Applied Probability 47, n^o 01 (mars 2010) : 277–92. http://dx.doi.org/10.1017/s0021900200006549.

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The inverse stochastic dominance of degree r is a stochastic order of interest in several branches of economics. We discuss it in depth, the central point being the characterization in terms of the weak r-majorization of the vectors of expected order statistics. The weak r-majorization (a notion introduced in the paper) is a natural extension of the classical (reverse) weak majorization of Hardy, Littlewood and Pòlya. This work also shows the equivalence between the continuous majorization (of higher order) and the discrete r-majorization. In particular, our results make it clear that the cases r = 1, 2 differ substantially from those with r ≥ 3, a fact observed earlier by Muliere and Scarsini (1989), among other authors. Motivated by this fact, we introduce new stochastic orderings, as well as new social inequality indices to compare the distribution of the wealth in two populations, which could be considered as natural extensions of the first two dominance rules and the S-Gini indices, respectively.

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Ricky Chee-Jiun Chia, Venus Khim-Sen Liew et Racquel Rowland. « Daily New Covid-19 Cases, the Movement Control Order, and Malaysian Stock Market Returns ». International Journal of Business and Society 21, n^o 2 (21 juillet 2020) : 553–68. http://dx.doi.org/10.33736/ijbs.3271.2020.

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The Movement Control Order (MCO) not only restricts movement of human being, it also reduces firms’ financial profits and brings significant impact to stock returns. The objective of this study is to examine the relation between Malaysian stock market returns and variables related to the novel Coronavirus (COVID-19) pandemic outbreak. The FTSE Bursa Malaysia KLCI Index and eight selected main indices from 2 January 2020 to April 30, 2020, which includes the first three MCOs, are considered in this study. The results show that daily new confirmed COVID-19 cases and deaths had negative but insignificant impact on the returns on indices. Interestingly, MCO had significant and positive impact on all the indices’ returns while oversea financial risks had negative impact on these returns. Furthermore, it is found that the degree of impacts of MCO and oversea financial risks varied positively with the firm size of the indices’ constituent companies. China’s decision on unchanged loan prime rate on the 20 February 2020 was a favorable news to the Malaysia stock markets as indicated by the positive returns on all the indices. Similarly, the degree of impact of the China interest policy also varied positively with the firms’ characteristics. These findings are useful for investors in the Bursa Malaysia to manage their investment portfolios based on their appetites for risk.

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Alimon, Nur Idayu, Nor Haniza Sarmin et Ahmad Erfanian. « Topological indices of non-commuting graph of dihedral groups ». Malaysian Journal of Fundamental and Applied Sciences 14 (25 octobre 2018) : 473–76. http://dx.doi.org/10.11113/mjfas.v14n0.1270.

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Assume is a non-abelian group A dihedral group is the group of symmetries of a regular polygon, which includes rotations and reflections. The non-commuting graph of denoted by is the graph of vertex set whose vertices are non-central elements, in which is the center of and two distinct vertices and are joined by an edge if and only if In this paper, some topological indices of the non-commuting graph, of the dihedral groups, are presented. In order to determine the Edge-Wiener index, First Zagreb index and Second Zagreb index of the non-commuting graph, of the dihedral groups, previous results of some of the topological indices of non-commuting graph of finite group are used. Then, the non-commuting graphs of dihedral groups of different orders are found. Finally, the generalisation of Edge-Wiener index, First Zagreb index and Second Zagreb index of the non-commuting graphs of dihedral groups are determined.

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Ali, Usman, Muhammad Javaid et Abdulaziz Mohammed Alanazi. « Computing Analysis of Connection-Based Indices and Coindices for Product of Molecular Networks ». Symmetry 12, n^o 8 (7 août 2020) : 1320. http://dx.doi.org/10.3390/sym12081320.

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Gutman and Trinajstić (1972) defined the connection-number based Zagreb indices, where connection number is degree of a vertex at distance two, in order to find the electron energy of alternant hydrocarbons. These indices remain symmetric for the isomorphic (molecular) networks. For the prediction of physicochemical and symmetrical properties of octane isomers, these indices are restudied in 2018. In this paper, first and second Zagreb connection coindices are defined and obtained in the form of upper bounds for the resultant networks in the terms of different indices of their factor networks, where resultant networks are obtained from two networks by the product-related operations, such as cartesian, corona, and lexicographic. For the molecular networks linear polynomial chain, carbon nanotube, alkane, cycloalkane, fence, and closed fence, first and second Zagreb connection coindices are computed in the consequence of the obtained results. An analysis of Zagreb connection indices and coindices on the aforesaid molecular networks is also included with the help of their numerical values and graphical presentations that shows the symmetric behaviour of these indices and coindices with in certain intervals of order and size of the under study (molecular) networks.

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Liu, Hechao, Lihua You et Yufei Huang. « Ordering chemical graphs by Sombor indices and its applications ». match Communications in Mathematical and in Computer Chemistry 87, n^o 01 (2021) : 5–22. http://dx.doi.org/10.46793/match.87-1.005l.

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Topological indices are a class of numerical invariants that predict certain physical and chemical properties of molecules. Recently, two novel topological indices, named as Sombor index and reduced Sombor index, were introduced by Gutman, defined as where denotes the degree of vertex in . In this paper, our aim is to order the chemical trees, chemical unicyclic graphs, chemical bicyclic graphs and chemical tricyclic graphs with respect to Sombor index and reduced Sombor index. We determine the first fourteen minimum chemical trees, the first four minimum chemical unicyclic graphs, the first three minimum chemical bicyclic graphs, the first seven minimum chemical tricyclic graphs. At last, we consider the applications of reduced Sombor index to octane isomers.

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Opekunova, M. Y., A. V. Bardash et S. A. Tukhta. « Structural analysis of river basins of the Upper Angara region ». Geodesy and Cartography 929, n^o 11 (20 décembre 2017) : 50–59. http://dx.doi.org/10.22389/0016-7126-2017-929-11-50-59.

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Oyek-river basin (right tributary of the Kuda-river) was used as a model site for revealing the features of the structure of river basins in the low-water karst region. Using the methodical approach of the Horton analysis, which was improved by Yu. G. Simonov, the main structural indices of the basin - bifurcation indices, lengths, areas, slopes, geomorphological work for sub-basins of the third order were determined. An analysis of the distribution of indices showed the greatest spread of the western part of the basin in the upper links of the erosion network. It is determined that the third-order sub-basins located in the western part within the Irkutsk-Cheremkhovskaya plain have the greatest homogeneity of structural indices, and the sub-basins of the Kudinskaya depression have the greatest diversity in the distribution of structural indices. An analysis of the distribution of the indicators of geomorphological work showed that significant work on the transfer of matter is performed by tributaries of the first orders of the western part of the basin, and maximum inflows are carried out in tributaries in the basins with the largest areas.

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Kala, Zdeněk. « New Importance Measures Based on Failure Probability in Global Sensitivity Analysis of Reliability ». Mathematics 9, n^o 19 (29 septembre 2021) : 2425. http://dx.doi.org/10.3390/math9192425.

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This article presents new sensitivity measures in reliability-oriented global sensitivity analysis. The obtained results show that the contrast and the newly proposed sensitivity measures (entropy and two others) effectively describe the influence of input random variables on the probability of failure Pf. The contrast sensitivity measure builds on Sobol, using the variance of the binary outcome as either a success (0) or a failure (1). In Bernoulli distribution, variance Pf(1 − Pf) and discrete entropy—Pfln(Pf) − (1 − Pf)ln(1 − Pf) are similar to dome functions. By replacing the variance with discrete entropy, a new alternative sensitivity measure is obtained, and then two additional new alternative measures are derived. It is shown that the desired property of all the measures is a dome shape; the rise is not important. Although the decomposition of sensitivity indices with alternative measures is not proven, the case studies suggest a rationale structure of all the indices in the sensitivity analysis of small Pf. The sensitivity ranking of input variables based on the total indices is approximately the same, but the proportions of the first-order and the higher-order indices are very different. Discrete entropy gives significantly higher proportions of first-order sensitivity indices than the other sensitivity measures, presenting entropy as an interesting new sensitivity measure of engineering reliability.

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Jin, Jia, Bayu Arief Pratama et Quan Wang. « Tracing Leaf Photosynthetic Parameters Using Hyperspectral Indices in an Alpine Deciduous Forest ». Remote Sensing 12, n^o 7 (1 avril 2020) : 1124. http://dx.doi.org/10.3390/rs12071124.

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Leaf photosynthetic parameters are important in understanding the role of photosynthesis in the carbon cycle. Conventional approaches to obtain information on the parameters usually involve long-term field work, even for one leaf sample, and are, thus, only applicable to a small area. The utilization of hyperspectral remote sensing especially of various vegetation indices is a promising approach that has been attracting increasing attention recently. However, most hyperspectral indices are only applicable to a specific area and specific forest stands, depending heavily on the conditions from which the indices are developed. In this study, we tried to develop new hyperspectral indices for tracing the two critical photosynthetic parameters (the maximum rate of carboxylation, Vcmax and the maximum rate of electron transport, Jmax) that are at least generally applicable for alpine deciduous forests, based on original hyperspectral reflectance, first-order derivatives, and apparent absorption spectra. In total, ten types of hyperspectral indices were screened to identify the best indices, and their robustness was determined using the ratio of performance to deviation (RPD) and Akaike’s Information Criterion corrected (AICc). The result revealed that the double differences (DDn) type of indices using the short-wave infrared (SWIR) region based on the first-order derivatives spectra performed best among all indices. The specific DDn type of indices obtained the RPD values of 1.43 (R2 = 0.51) for Vcmax and 1.68 (R2 = 0.64) for Jmax, respectively. These indices have also been tested using the downscaled dataset to examine the possibilities of using hyperspectral data derived from satellite-based information. These findings highlight the possibilities of tracing photosynthetic capacity using hyperspectral indices.

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Soares, Bárbara Santos, Alisson Carraro Borges, Antonio Teixeira de Matos, Rubens Barrichello Gomes Barbosa et Fabyano Fonseca e. Silva. « Exploring the Removal of Organic Matter in Constructed Wetlands Using First Order Kinetic Models ». Water 14, n^o 3 (5 février 2022) : 472. http://dx.doi.org/10.3390/w14030472.

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Mathematical models have become an excellent tool to evaluate the characteristics and performance of Constructed Wetlands (CWs). They help to characterize the dynamics of pollutant removal in these systems. The aim of this research was to evaluate the kinetics of organic matter removal in CWs using two models: (i) the conventional first order model and (ii) the sigmoidal or k-n model. For this purpose, data from 41 CWs where domestic sewage is treated were used. The cluster analysis was performed to identify similar groups of CWs based on the estimation of model coefficients. According to the results obtained, the model that provides a better fit for the removal of organic matter in CWs is the sigmoidal-type. However, its “n” coefficient, which would represent an increase in resistance to degradation, remains a not totally explained variable. The sigmoidal or k-n model is promising, presenting good adjustment indices.

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Aslam, Adnan, Safyan Ahmad, Muhammad Ahsan Binyamin et Wei Gao. « Calculating topological indices of certain OTIS interconnection networks ». Open Chemistry 17, n^o 1 (10 avril 2019) : 220–28. http://dx.doi.org/10.1515/chem-2019-0029.

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AbstractRecently, increasing attention has been paid to The Optical Transpose Interconnection System (OTIS) network because of its prospective applications in architectures for parallel as well as distributed systems [27, 28]. Different interconnection networks in the context of topological indices are researched recently in [25, 26]. This article includes the computions of the general Randi´c, first and second Zagreb, general sum connectivity, first and second multiple zagreb, hyper zagreb, ABC and GA indices for OTIS (swapped and biswapped) networks by taking path and k-regular graph on n vertices as a base graphs. In addition, some delicated formulas are also obtained for the ABC4 and GA5 indices for the OTIS biswapped networks by considering basis graph as a path and k-regular graph of order n.

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Popoola, Jumoke, Waheed Babatunde Yahya, Olusogo Popoola et Oyebayo Ridwan Olaniran. « Generalized Self-Similar First Order Autoregressive Generator (GSFO-ARG) for Internet Traffic ». Statistics, Optimization & ; Information Computing 8, n^o 4 (6 août 2020) : 810–21. http://dx.doi.org/10.19139/soic-2310-5070-926.

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Internet traffic data such as the number of transmitted packets and time spent on the transmission of Internet protocols (IPs) have been shown to exhibit self-similar property which can contain the long memory property, particularly in a heavy Internet traffic. Simulating this type of dataset is an important aspect of delay avoidance planning, especially when trying to mimic real-life processing of packets on the Internet. Most of the existing procedures often assumed the process follows a Gaussian distribution, and thus long memory processes such as Fractional Brownian Motion (FBM) and Fractional Gaussian Noise (FGN) among others are used. These approaches often result in estimation errors arising from the use of inappropriate distribution. However, it has been established that the distribution of Internet processes are heavy-tailed. Therefore, in this paper, a new method that is capable of generating heavy-tailed self-similar traffic is proposed based on the first-order autoregressive AR (1) process. The proposed method is compared with some of the existing methods at varying values of the self-similar index and sample sizes. The imposed self-similarity indices were estimated using the Range/Standard deviation statistic (R/S). Performance analysis was achieved using the absolute percentage errors. The results showed that the proposed method has a lower average error when compared with other competing methods.

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Blickstein, I., R. Namir, A. Weissman et Y. Diamant. « The Influence of Birth Order and Presentation on Intrauterine Growth of Twins ». Acta geneticae medicae et gemellologiae : twin research 42, n^o 2 (avril 1993) : 151–58. http://dx.doi.org/10.1017/s000156600000204x.

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AbstractIn order to evaluate the influence of birth order and fetal presentation on antenatal growth of twins we conducted a comparison of prospective measurements of five fetal biometric indices in 50 vertex-vertex and 47 vertex-breech twins. We compared (a) twin A to twin B in both groups; (b) the second and (c) the first twins of both groups. Both groups had similar maternal and neonatal characteristics. The growth curves of the twins were also very similar except for three significant (p<0.05) deviations: (a) Twin A of the vertex-vertex group, had larger femur length (FL) at 18-19 weeks, abdominal circumference (AC) and estimated fetal weight (EFW) at 29 weeks, and EFW measurements at 36 weeks, (b) Second breech twins, compared to their second vertex cohorts, had significantly smaller biparietal diameter (BPD), head circumference (HC) and FL at 18-19 weeks, BPD and HC at 29 weeks, and EFW at 37 weeks, (c) First twins of the vertex-breech group, as compared to first twins of the vertex-vertex group, had significantly smaller BPD and AC at 18-19 weeks, FL and AC at 21-22 and 29 weeks, FL at 31 weeks, and EFW at 27-28 and 36 weeks' gestation. We concluded that significantly different sonographic fetal indices may be measured at about 20 and 30 weeks' gestation, but not later. An adaptive mechanism attributed to fetal presentation is suggested to explain similar birthweights in spite of these antepartum differences.

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D'ELIA, M., A. DI GIACOMO et C. PICA. « ON THE ORDER OF THE DECONFINING TRANSITION IN Nf = 2 QCD ». International Journal of Modern Physics A 20, n^o 19 (30 juillet 2005) : 4579–84. http://dx.doi.org/10.1142/s0217751x05028235.

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A careful study is made on the lattice of the phase diagram of QCD with two staggered flavors, to investigate the order of the chiral transition of Nf = 2 QCD. The specific heat and the susceptibility of the chiral condensate are determined for different spatial sizes of the system, and a finite size scaling analysis provides a determination of the (pseudo)critical indices. The result is a strong indication that the chiral transition is first order.

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Won, J. H., B. W. Choi et M. J. Chung. « A unified approach to the inverse kinematic solution for a redundant manipulator ». Robotica 11, n^o 2 (mars 1993) : 159–65. http://dx.doi.org/10.1017/s0263574700019263.

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SUMMARYFor a kinematically redundant manipulator, some performance indices can be optimized while carrying out a given task. So far, the redundancy resolution has been solved at the joint angle level, the joint velocity level, or joint acceleration level depending on the performance indices. According to the resolution level, the solution is represented by high-order differential equations or superfluous number of equations. We propose a unified approach to the inverse kinematic solution which optimizes it at the joint velocity level regardless of the types of the performance indices. A unified approach to obtain an optimal joint velocity is derived by using the necessary condition for optimality so that the proposed method provides an optimal solution for any performance indices and tasks. The optimal solution becomes a set of the minimum number of first-order differential equations which requires a minimum search dimension.To show the validity of the approach, it is applied to a three-link planar manipulator for various types of performance indices.

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Mogilevskii, Vadim. « Boundary pairs and boundary conditions for general (not necessarily definite) first-order symmetric systems with arbitrary deficiency indices ». Mathematische Nachrichten 285, n^o 14-15 (21 juin 2012) : 1895–931. http://dx.doi.org/10.1002/mana.201100241.

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Xu, Hongyan, Guangsheng Chen, Hari Mohan Srivastava, Hong Li, Zuxing Xuan et Yongqin Cui. « A Study of the Growth Results for the Hadamard Product of Several Dirichlet Series with Different Growth Indices ». Mathematics 10, n^o 13 (24 juin 2022) : 2220. http://dx.doi.org/10.3390/math10132220.

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In this paper, our first purpose is to describe a class of phenomena involving the growth in the Hadamard–Kong product of several Dirichlet series with different growth indices. We prove that (i) the order of the Hadamard–Kong product series is determined by the growth in the Dirichlet series with smaller indices if these Dirichlet series have different growth indices; (ii) the q1-type of the Hadamard–Kong product series is equal to zero if p Dirichlet series are of qj-regular growth, and q1<q2<⋯<qp, qj∈N+, j=1,2,…,p. The second purpose is to reveal the properties of the growth in the Hadamard–Kong product series of two Dirichlet series—when one Dirichlet series is of finite order, the other is of logarithmic order, and two Dirichlet series are of finite logarithmic order—and obtain the growth relationships between the Hadamard–Kong product series and two Dirchlet series concerning the order, the logarithmic order, logarithmic type, etc. Finally, some examples are given to show that our results are best possible.

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Ponec, Robert, David L. Cooper et Peter B. Karadakov. « Are Multicentre Bond Indices and Related Quantities Reliable Predictors of Excited-State Aromaticity ? » Molecules 25, n^o 20 (19 octobre 2020) : 4791. http://dx.doi.org/10.3390/molecules25204791.

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Systematic scrutiny is carried out of the ability of multicentre bond indices and the NOEL-based similarity index dAB to serve as excited-state aromaticity criteria. These indices were calculated using state-optimized complete active-space self-consistent field wavefunctions for several low-lying singlet and triplet states of the paradigmatic molecules of benzene and square cyclobutadiene and the inorganic ring S2N2. The comparison of the excited-state indices with aromaticity trends for individual excited states suggested by the values of magnetic aromaticity criteria show that whereas the indices work well for aromaticity reversals between the ground singlet and first triplet electronic states, addressed by Baird’s rule, there are no straightforward parallels between the two sets of data for singlet excited states. The problems experienced while applying multicentre bond indices and dAB to singlet excited states are explained by the loss of the information inherently present in wavefunctions and/or pair densities when calculating the first-order density matrix.

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Gao, Fang, Xiaoxin Li, Kai Zhou et Jia-Bao Liu. « The Extremal Graphs of Some Topological Indices with Given Vertex k-Partiteness ». Mathematics 6, n^o 11 (21 novembre 2018) : 271. http://dx.doi.org/10.3390/math6110271.

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The vertex k-partiteness of graph G is defined as the fewest number of vertices whose deletion from G yields a k-partite graph. In this paper, we characterize the extremal value of the reformulated first Zagreb index, the multiplicative-sum Zagreb index, the general Laplacian-energy-like invariant, the general zeroth-order Randić index, and the modified-Wiener index among graphs of order n with vertex k-partiteness not more than m .

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Martínez-Pérez, Álvaro, et José M. Rodríguez. « New Bounds for Topological Indices on Trees through Generalized Methods ». Symmetry 12, n^o 7 (2 juillet 2020) : 1097. http://dx.doi.org/10.3390/sym12071097.

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Topological indices are useful for predicting the physicochemical behavior of chemical compounds. A main problem in this topic is finding good bounds for the indices, usually when some parameters of the graph are known. The aim of this paper is to use a unified approach in order to obtain several new inequalities for a wide family of topological indices restricted to trees and to characterize the corresponding extremal trees. The main results give upper and lower bounds for a large class of topological indices on trees, fixing or not the maximum degree. This class includes the first variable Zagreb, the Narumi–Katayama, the modified Narumi–Katayama and the Wiener index.

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Rao, M. Ramakrishna Nanachara, P. V. Datta Prasad, V. G. K. M. Pisipati et D. Madhavi Latha. « An Optical Study on Orientational Order Parameter and Molecular Polarizability in Benzylidene Anilines ». Solid State Phenomena 181-182 (novembre 2011) : 102–5. http://dx.doi.org/10.4028/www.scientific.net/ssp.181-182.102.

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Refractive indices measurements are carried out in four alkoxy benzylidene anilines viz., N-(p-n-methoxy and ethoxy benzaldehyde)-p-n-dodecyl and tetra decyl anilines, 1O.12, 1O.14, 2O.12 and 2O.14. First three compounds exhibit monovariant nematic phase while the last compound exhibits nematic and SmA phases with variable thermal ranges. The molecular polarizabilities are calculated from the refractive indices and the density using the well known internal field models by Vuks and Neugebauer. The molecular polarizability anisotropy is estimated from the Lippincott δ-function model as well as molecular vibrational methods. The order parameter is estimated using a) from the Haller’s extrapolation from molecular polarizabilities, b) from the scaling factors obtained from the equations by Vuks and Neugbeaur and c) directly from the birefringence - a method developed by Kuczynski et al without considering any internal field model to the liquid crystal molecule. The results evaluated from these methods are compared from one another and the limitations of the methods used are discussed.

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Kanwal, Salma, Shanshan Shang, Muhammad Kamran Siddiqui, Tahira Sumbal Shaikh, Ammara Afzal et Anton Asare-Tuah. « On Analysis of Topological Aspects for Subdivision of Kragujevac Tree Networks ». Mathematical Problems in Engineering 2021 (3 novembre 2021) : 1–15. http://dx.doi.org/10.1155/2021/9082320.

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In this paper, we have taken review of certain topological topological characteristics of subdivision and the line graph of subdivision of Kragujevac tree. A Kragujevac tree is denoted by K , K ∈ Kg q = r 2 t + 1 + 1 , r , with order r 2 t + 1 + 1 and size r 2 t + 1 , respectively. We have computed the Zagreb polynomials, forgotten polynomial, and M-polynomial for Kragujevac tree. Moreover, we have computed topological indices like Zagreb-type indices, reduced reciprocal Randić indices, family of Gourava indices as well as forgotten index. Further, some topological indices that can be directly derived from M-polynomial, i.e., first and second Zagreb index, modified second Zagreb index, Randić and reciprocal Randić index, symmetric division and harmonic index, and inverse sum and augmented Zagreb index are also computed.

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Santos, Vanessa Cristina Dos, Mhamad El Hage, Laurent Polidori et José Cândido Stevaux. « EFFECT OF DIGITAL ELEVATION MODEL MESH SIZE ON GEOMORPHIC INDICES : A CASE STUDY OF THE IVAÍ RIVER WATERSHED - STATE OF PARANÁ, BRAZIL ». Boletim de Ciências Geodésicas 23, n^o 4 (décembre 2017) : 684–99. http://dx.doi.org/10.1590/s1982-21702017000400045.

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Abstract: Geomorphometry is the science of quantitative description of land surface morphology by the mean of geomorphic indices extracted from Digital Elevation Models (DEMs). The analysis of these indices is the first and most common procedure performed in several geoscience-related subjects. This study aims to assess the impact of mesh size degradation on different local and regional geomorphic indices extracted for GDEM and TOPODATA DEMs. Thus, these DEMs, having a mesh size of 30 m, were subsampled to 60, 120 and 240 m and then geomorphic indices were calculated using the full resolution DEM and the subsampled ones. Depending on their behavior, these indices are then classified into stable and unstable. The results show that the most affected indices are slope and hydrographic indices such as Strahler order, stream sinuosity and fractal dimension and watershed perimeter, whereas elevation remains stable. It also shows that the effect depends on the presence of the canopy and geological structures in the studied area.

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Imran, Muhammad, Shehnaz Akhter et Muhammad Kamran Jamil. « Computation of Topological Indices of NEPS of Graphs ». Complexity 2021 (14 juin 2021) : 1–6. http://dx.doi.org/10.1155/2021/9911226.

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The inspection of the networks and graphs through structural properties is a broad research topic with developing significance. One of the methods in analyzing structural properties is obtaining quantitative measures that encode data of the whole network by a real quantity. A large quantity of graph-associated numerical invariants has been used to examine the whole structure of networks. In this analysis, degree-related topological indices have a significant place in nanotechnology and theoretical chemistry. Thereby, the computation of indices is one of the successful branches of research. The noncomplete extended p -sum NEPS of graphs is a famous general graph product. In this paper, we investigated the exact formulas of general zeroth-order Randić, Randić, and the first multiplicative Zagreb indices for NEPS of graphs.

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Tejeda-Ochoa, D. A., G. E. Peralta-Peñuñuri, V. A. González-Huitrón, H. Rodríguez-Rangel, R. Baray-Arana et A. E. Rodríguez-Mata. « New System for Angular Velocity Estimation for a First-Order Manipulator Using Artificial Intelligence and Sliding Mode Differentiator ». Memorias del Congreso Nacional de Control Automático 5, n^o 1 (17 octobre 2022) : 362–67. http://dx.doi.org/10.58571/cnca.amca.2022.055.

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On a NVIDIA Jetson Nano device, this study illustrates a unique and original usage of automated control and artificial intelligence algorithms for angular velocity estimates of a first-order manipulator device. A platform can be used as a position estimation platform using computer vision and three state estimation algorithms: sliding mode differentiator, high gain observer, and static filter. A hybrid system for process performance improvement is proposed using computer vision and three state estimation algorithms: sliding mode differentiator, high gain observer, and static filter. The results of numerical simulations are provided, as well as real-time judgments. The ITAE and IAE indices reveal that the sliding mode differentiator is much superior in angular velocity estimation for position signals utilizing artificial intelligence sensors.

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Jafarova, H. A., et R. T. Aliyev. « The use of autoregressive process AR(1) in the analysis of some finance indices ». Informatics and Control Problems, n^o 1(3) (25 mai 2022) : 19–25. http://dx.doi.org/10.54381/icp.2022.1.03.

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The article considers an autoregressive process AR(1) with finance application. The solution of many control problems comes down to autoregressive process. We study the first-order autoregressive process AR(1) with application to the S&P500 and NASDAQ indices for 01/01/2017-01/08/2021. The main purpose of the study is to investigate the effects of the Covid-19 pandemic on stock indices. For statistical computing and visualization, R language and environment are used.

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Peng, Yu, Min Fan, Lan Bai, Weiguo Sang, Jinchao Feng, Zhixin Zhao et Ziye Tao. « Identification of the Best Hyperspectral Indices in Estimating Plant Species Richness in Sandy Grasslands ». Remote Sensing 11, n^o 5 (11 mars 2019) : 588. http://dx.doi.org/10.3390/rs11050588.

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Numerous spectral indices have been developed to assess plant diversity. However, since they are developed in different areas and vegetation type, it is difficult to make a comprehensive comparison among these indices. The primary objective of this study was to explore the optimum spectral indices that can predict plant species richness across different communities in sandy grassland. We use 7339 spectral indices (7217 we developed and 122 that were extracted from literature) to predict plant richness using a two-year dataset of plant species and spectra information at 270 plots. For this analysis, we employed cluster analysis, correlation analysis, and stepwise linear regression. The spectral variability within the 420–480 nm and 760–900 nm ranges, the first derivative value at the sensitive bands, and the normalized difference at narrow spectral ranges correlated well with plant species richness. Within the 7339 indices that were investigated, the first-order derivative values at 606 and 583 nm, the reflectance combinations on red bands: (R802 − R465)/(R802 + R681) and (R750 − R550)/(R750 + R550) showed a stable performance in both the independent calibration and validation datasets (R2 > 0.27, p < 0.001, RMSE < 1.7). They can be regarded as the best spectral indices to estimate plant species richness in sandy grasslands. In addition to these spectral variation indices, the first derivative values or the normalized difference of the sensitive bands also reflect plant diversity. These results can help to improve the estimation of plant diversity using satellite-based airborne and hand-held hyperspectral sensors.

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Grigoryan, G. V., M. C. Casper, J. Gauer, A. C. Vasconcelos et P. P. Reiter. « Impact of climate change on water balance of forest sites in Rhineland-Palatinate, Germany ». Advances in Geosciences 27 (25 août 2010) : 37–43. http://dx.doi.org/10.5194/adgeo-27-37-2010.

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Abstract. It is expected that the biomass productivity of forest stands will be influenced by global climate change. In order to adapt forest management to this fact a model based approach was developed in cooperation with forestry experts. The concept aims at detecting the link between climate, terrain and soil parameters with the biomass productivity of some tree species. This article gives an insight into the first two steps of this approach. At first the WaSiM-ETH 8.2 model was parameterised to simulate various forest sites. Furthermore, different drought stress indices were applied to the simulated water balance time series. The impact of variations of climate, topography and soil characteristics on water balance was plausibly simulated. All drought stress indices detected years which were dominated by dry conditions. However, the indices related to soil water content were more selective than those related to evapotranspiration. Drought stress indices for one future climate projection have shown an increasing frequency of drought stress during vegetation period. Thus, the first two steps are capable components to detect the link between water balance with climate, terrain and soil parameters.

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Zhang, Shi Lei, Shao Feng Chen, Huan Ding Wang et Wei Wang. « Evaluating Identification Indices on Damage Detection by a Fuzzy Analytical Hierarchy Process ». Advanced Materials Research 163-167 (décembre 2010) : 2934–40. http://dx.doi.org/10.4028/www.scientific.net/amr.163-167.2934.

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In order to evaluate the identification precision and the computational efficiency of identification indices on damage detection and provide a reasonable basis to choose identification indices for deeply developing structural damage identification, a fuzzy analytical hierarchy process is used to comprehensive analyse and assess nine kinds of identification indices. By establishing the mathematical relationship between the precedence relation matrix and the fuzzy judgement matrix, the consistency of the judgement matrix in analytical hierarchy process is effectively improved. Using above methods and based on three evaluation standards that include mean error, network scale and measuring difficulty , a fuzzy hierarchy to assess identification indices is set up. On the basis of the fuzzy judgement matrix, the performance of nine kinds of identification indices is ranked. Empirical results show that deflection, first modal shape and fundamental frequency are more suitable for identification indices than other indices. And a fuzzy judgement matrix can be established only using the relative relationship between identification indices in the fuzzy analytical hierarchy process. Thus, the fuzzy analytical hierarchy process can be convenient extended to evaluate other identification indices and effectively improve the identification precision and the computational efficiency on damage detection.

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Vasilieva, Svetlana, Inna Stepanenko et Kateryna Kravchuk. « Anthropometric parameters of first-year students of pedagogical specialties ». ScienceRise : Pedagogical Education, n^o 2(41) (31 mars 2021) : 15–18. http://dx.doi.org/10.15587/2519-4984.2021.228222.

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The topic is relevant due to a detailed study of the factors determining the health level of nowadays students, and taking these factors into consideration for the development of programs to strengthen their health. Since the scientific literary data on the physical development of student youth is somewhat contradictory, namely the morphological and functional indicators of a person depends on the level of physical health and adaptive capacity, it has been decided to determine the freshmen’s anthropometric parameters. The aim of the study was to take anthropometric measurements of total and comprehensive body size of 105 students studying at Vinnytsia Mykhailo Kotsiubynskyi State Pedagogical University, assess their compliance with anthropometric standards, determine the somatotype and foot shape in order to create a database for further monitoring of physical development and identify patterns of anthropometric indicators under conditions of modern learning technologies. Research methods. Anthropometric measurements were taken according to standard anthropometric methods suggested by V. V. Bunak [1]. Data estimation was performed by the method of centile intervals and indices. The foot shape was assessed by the plantogram based on the Chyzhyn index. The obtained data were statistically processed according to the STATISTICA 5.5 program. Research results. The peculiarities of anthropometric parameters and somatotype of Vinnytsia Mykhailo Kotsiubynskyi State Pedagogical University first-year students are established: height, body weight; girth sizes: chest, waist, hips; body mass index, Kettle mass-growth index, body harmony indices, foot shape

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Sattar, Aqsa, Muhammad Javaid et Md Nur Alam. « On the Studies of Dendrimers via Connection-Based Molecular Descriptors ». Mathematical Problems in Engineering 2022 (19 mars 2022) : 1–13. http://dx.doi.org/10.1155/2022/1053484.

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Topological indices (TIs) have been utilized widely to characterize and model the chemical structures of various molecular compounds such as dendrimers, neural networks, and nanotubes. Dendrimers are extraordinarily comprehensible, globular, artificially synthesized polymers with a structure of frequently branched units. A mathematical approach to characterize the molecular structures by manipulating the topological techniques, including numerical graphs invariants is the present-day line of research in chemistry. Among all the defined descriptors, the connection-based Zagreb indices are considered to be more effective than the other classical indices. In this manuscript, we find the general results to compute the Zagreb connection indices (ZCIs), namely, first ZCI (1st ZCI), second ZCI (2nd ZCI), modified 1st ZCI, modified 2nd ZCI, and modified 3rd ZCI. Furthermore, we compute the multiplicative ZCI (MZCI), namely, first MZCI (1st MZCI), second MZCI (2nd MZCI), third MZCI (3rd MZCI), fourth MZCI (4th MZCI), modified 1st MZCI, modified 2nd MZCI, and modified 3rd MZCI. In addition, we compare the calculated values with each other in order to check the superiority.

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Pisipati, Venkata G. K. M., Divi Madhavi Latha, Boddapati T. P. Madhav et Potapragada V. Datta Prasad. « Nematic/Smectic-A Transition (NSA), Location of Tri Critical Point (TCP) in nO.m Series – A Birefringence Study ». Zeitschrift für Naturforschung A 65, n^o 4 (1 avril 2010) : 335–41. http://dx.doi.org/10.1515/zna-2010-0410.

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The tri critical point (TCP), where the second-order transition transforms to first order has been located in nO.m homologous series. The order parameter has been estimated from the birefringence δn, from the refractive indices and from birefringence data available in literature and from those obtained at our laboratory on a number of nO.m compounds. The compounds in the nO.m series exhibit both second and first-order nematic/smectic-A (NSA) transition depending on the McMillan ratio (TNA/TIN) which in turn depends on the nematic and smectic-A thermal ranges. The data presented are compared with the body of the data available on this homologous series obtained with other techniques.

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Bino, Athira, et Murugan . « Topological Indices of Molecular Graph and Drug Design ». International Journal for Research in Applied Science and Engineering Technology 10, n^o 11 (30 novembre 2022) : 1470–72. http://dx.doi.org/10.22214/ijraset.2022.47629.

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Abstracts: The application of topology in molecular graph and drug design is covered in this article. On the basis of the most recent developments in this area, an overview of the use of topological indices (TIs) in the process of drug design and development is provided. The introduction of concepts used in drug design and discovery, graph theory, and topological indices is the primary goal of the first section of this book. Researchers can learn more about the physical characteristics, chemical reactivity, and biological activity of these chemical molecular structures by using topological indices. In order to compensate for the lack of chemical experiments and offer a theoretical foundation for the production of medications and chemical materials, topological indices on the chemical structure of chemical materials and drugs are studied. In this article, we concentrate on the family of smart polymers that are frequently utilised in the production of drugs

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Bezgodova, O. V. « Structural and Morphometric Analysis of the Ihe-Ukhgun Small River Basin (Irkut River Basin) ». Bulletin of Irkutsk State University. Series Earth Sciences 37 (2021) : 3–16. http://dx.doi.org/10.26516/2073-3402.2021.37.3.

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The article is devoted to the structural and morphometric analysis of a small rivers using the example of the Ihe-Ukhgun river basin (left tributary of the Irkut river), which is based on a complex processing of a digital elevation model (DEM). The author has prepared a hydrologically correct DEM based on the ALOS Digital Surface Model (DSM) satellite data, carried out an automated calculation and mapping of the basin erosion network based on the DEM data, calculated the structural indicators of the third-order basins for analyzing the basin organization of the small rivers network. Structural and morphometric analysis using GIS was practically not used for the Ihe-Ukhgun river basin which is placed in different landscapes, geological and geomorphological conditions. The work is based on geomorphometric and structural morphometric methods as well as the method of geoinformation mapping and relief modeling for analyzing lower-order basins. Thalweg erosion network modeling up to the fourth order of the river basin Ihe-Uhgun was carried out with using of DEM analysis in the ArcGIS 10 program. The map of the erosional network of the basin was constructed, morphometric indicators of rivers (length, area of basins, sum of slopes, coefficient of basin asymmetry, etc.) were obtained, and then the indices of the basin structure (structure of bifurcation, lengths, areas and slopes) were calculated. As a result, an asymmetric erosion network was revealed, which indicates a great work in the transfer of matter of first-order streams. First-order streams exceed those of the second and third orders streams in terms of catchment area, length and steepness of adjacent slopes. The interrelation of morphometric characteristics of different-order streams within third order sub-basins are most fully traced with the using of structural indices and their comparison with modal indicators. In general, the Ihe-Ukhgun river basin is characterized by a heterogeneous structure of the streams ratio of the first, second and third orders. The basins of the Khurguta, Khubyty and Ulan-Gol rivers have the highest degree of homogeneity. At the same time, for the Ihe-Ukhgun river basin, there is no direct relationship with the area of the third order drainage basins.

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Kala, Zdeněk. « Sensitivity Analysis in Probabilistic Structural Design : A Comparison of Selected Techniques ». Sustainability 12, n^o 11 (11 juin 2020) : 4788. http://dx.doi.org/10.3390/su12114788.

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Although more and more reliability-oriented sensitivity analysis (ROSA) techniques are now available, review and comparison articles of ROSA are absent. In civil engineering, many of the latest indices have never been used to analyse structural reliability for very small failure probability. This article aims to analyse and compare different sensitivity analysis (SA) techniques and discusses their strengths and weaknesses. For this purpose, eight selected sensitivity indices are first described and then applied in two different test cases. Four ROSA type indices are directly oriented on the failure probability or reliability index beta, and four other indices (of a different type) are oriented on the output of the limit state function. The case study and results correspond to cases under common engineering assumptions, where only two independent input variables with Gaussian distribution of the load action and the resistance are applied in the ultimate limit state. The last section of the article is dedicated to the analysis of the different results. Large differences between first-order sensitivity indices and very strong interaction effects obtained from ROSA are observed for very low values of failure probability. The obtained numerical results show that ROSA methods lack a common platform that clearly interprets the relationship of indices to their information value. This paper can help orientate in the selection of which sensitivity measure to use.

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Watanabe, Pedro Henrique, Tatianne Alexandre Azevedo, Margarita Augusto do Nascimento Silva, Nathalia Martins Oliveira, Thalles Ribeiro Gomes, Tiago Silva Andrade et José Antônio Delfino Barbosa Filho. « Cooling ventilation at farrowing for sows from first to third parturition ». Comunicata Scientiae 9, n^o 4 (4 janvier 2019) : 556–64. http://dx.doi.org/10.14295/cs.v9i4.1098.

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This study aimed to evaluate the thermal comfort considering natural and cooling ventilation on the performance, physiological parameters and thermal comfort indices for sows from first to third parturition. A total of 30 sows from commercial lineage (genetic base Landrace x Large White) initially weighing 252.3±5.7, 280.8±9.5 and 324.5±4.8 kg at first, second and third parturition, respectively, were distributed in a 3x2 factorial arrangement, considering the three parturition orders and the two ventilation methods, with five replicas per treatment. The effect of ventilation methods and times of the day on relative humidity, radiant thermal load, temperature and humidity index and black globe humidity index. There was an interaction among ventilation methods and parturition order for sow weight at weaning and daily feed intake. Regarding the females physiological parameters, with the exception of rectal temperature, there was an interaction between ventilation methods and times of the day. The thermal conditioning using cooling ventilation provides better values for thermal comfort indexes of the sows and promotes an increase in feed intake, mainly in gilts.

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