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 Author:
 Hosseini, Amin
 Source:
 Journal of Taibah University for Science 2017 v.11 no.2 pp. 332336
 ISSN:
 16583655
 Subject:
 mathematics
 Abstract:
 ... This study is an attempt to prove the following result:Suppose that R is a 2torsion free prime ring and Φ:R×R→R is a left two variable σderivation such that σ is a monomorphism, Φ(R×R)⊆σ(R), and [σ(b)−b, x]=0 for all b∈I and x∈R, where I is an arbitrary fixed nonzero ideal of R. Moreover, assume that I⊆σ(I) or σ(I) is an ideal of R. If [σ(a),Φ(a,x)]∈Z(R) for all a∈I and x∈R, then either R is co ...
 DOI:
 10.1016/j.jtusci.2016.03.004

https://dx.doi.org/10.1016/j.jtusci.2016.03.004
 Author:
 Sajid, Mohammad
 Source:
 Journal of Taibah University for Science 2017 v.11 no.2 pp. 324327
 ISSN:
 16583655
 Subject:
 mathematics
 Abstract:
 ... The singular values of two kinds of twoparameter families of functions (i) fλ,μ(z)=λ((bz−1)/z)μ and fλ,μ(0)=λ(lnb)μ, μ>0, (ii) gλ,η(z)=λ(z/(bz−1))η and gλ,η(0)=λ/(lnb)η, η>0; λ∈ℝ∖{0}, z∈ℂ, b>0, b≠1 are described. It is shown that all the critical values of fλ,μ(z) and gλ,η(z) lie interior and exterior of the disk centered at origin and having radii λ(lnb)μ and λ/(lnb)η respectively. Further, ...
 DOI:
 10.1016/j.jtusci.2016.03.005

https://dx.doi.org/10.1016/j.jtusci.2016.03.005
 Author:
 AriasCastro, Ery; Pu, Xiao
 Source:
 Computational statistics & data analysis 2017 v.105 pp. 217228
 ISSN:
 01679473
 Subject:
 mathematics
 Abstract:
 ... Consider the problem of sparse clustering, where it is assumed that only a subset of the features are useful for clustering purposes. In the framework of the COSA method of Friedman and Meulman, subsequently improved in the form of the Sparse Kmeans method of Witten and Tibshirani, a natural and simpler hillclimbing approach is introduced. The new method is shown to be competitive with these two ...
 DOI:
 10.1016/j.csda.2016.08.003

http://dx.doi.org/10.1016/j.csda.2016.08.003
 Author:
 Piel, Helen
 Source:
 Journal of the history of biology 2019 v.52 no.3 pp. 371390
 ISSN:
 00225010
 Subject:
 mathematics, etc ; evolution; penguins; Show all 3 Subjects
 Abstract:
 ... Popular science writing has received increasing interest, especially in its relation to professional science. I extend the current scholarly focus from the nineteenth to the twentieth century by providing a microhistory of the early popular writings of evolutionary biologist John Maynard Smith (1920–2004). Linking them to the state of evolutionary biology as a professional science as well as Mayna ...
 DOI:
 10.1007/s107390199566y

http://dx.doi.org/10.1007/s107390199566y
 Author:
 Tseng, YuTi; Pan, HaoJen; Ward, Jeffrey D.
 Source:
 Industrial & engineering chemistry process design and development 2019 v.58 no.31 pp. 1423914251
 ISSN:
 15205045
 Subject:
 mathematics, etc ; crystallization; process design; Show all 3 Subjects
 Abstract:
 ... Pontryagin’s minimum principle is applied to determine Paretooptimal fronts for multiobjective optimization of seeded batch crystallization processes. For cases with two objectives, when both objectives are based on properties of the higher moments or lower moments of the crystal size distribution (for example, weight mean size and weight mean coefficient of variation), there is relatively little ...
 DOI:
 10.1021/acs.iecr.9b02394

http://dx.doi.org/10.1021/acs.iecr.9b02394
 Author:
 Ricotta, C.
 Source:
 Community ecology 2019 v.20 no.1 pp. 104106
 ISSN:
 15882756
 Subject:
 mathematics, etc ; ecologists; species abundance; Show all 3 Subjects
 Abstract:
 ... To avoid the problems associated with the Euclidean distance for the calculation of plottoplot dissimilarity, a variety of alternative measures have been proposed. Among them, the chord and the Hellinger distances are both obtained by first transforming separately the species abundances in each plot vector and then by calculating the Euclidean distance on the chordtransformed or the Hellingert ...
 DOI:
 10.1556/168.2019.20.1.11

http://dx.doi.org/10.1556/168.2019.20.1.11
 Author:
 Bak, Britta Anker; Jensen, Jens Ledet
 Source:
 Computational statistics & data analysis 2016 v.98 pp. 4659
 ISSN:
 01679473
 Subject:
 mathematics
 Abstract:
 ... A binary classification problem is imbalanced when the number of samples from the two groups differs. For the high dimensional case, where the number of variables is much larger than the number of samples, imbalance leads to a bias in the classification. The independence classifier is studied theoretically and based on the analysis two new classifiers are suggested that can handle any imbalance ra ...
 DOI:
 10.1016/j.csda.2015.12.009

http://dx.doi.org/10.1016/j.csda.2015.12.009
 Author:
 Yadav, Akhilesh Chandra
 Source:
 National Academy science letters 2019 v.42 no.3 pp. 245247
 ISSN:
 0250541X
 Subject:
 mathematics, etc ; data analysis; equations; statistics; Show all 4 Subjects
 Abstract:
 ... Attempts have been made to introduce notion of class assigned functions k for a given group G and observed that it determines a right gyrogroup [Formula: see text]. It is also observes that [Formula: see text] will be a group if and only if G is a nilpotent group of class 2 and will be a gyrogroup for a nilpotent group of class 3, where [Formula: see text] for all [Formula: see text]. ...
 DOI:
 10.1007/s4000901807213

https://dx.doi.org/10.1007/s4000901807213
 Author:
 Kakkar, Vipul
 Source:
 National Academy science letters 2019 v.42 no.3 pp. 295
 ISSN:
 0250541X
 Subject:
 mathematics, etc ; data analysis; equations; topology; Show all 4 Subjects
 Abstract:
 ... Being motivated by Suvorov and Kryuchkov (Sib Mat Zh 17(2):471–473, 1976) and Suvorov (Sib Mat Zh 32(5):193, 1991), an example of a right loop admitting only discrete topologization is presented in this paper. ...
 DOI:
 10.1007/s40009019008211

https://dx.doi.org/10.1007/s40009019008211
 Author:
 Cheong, Kang Hao; Koh, Jin Ming; Jones, Michael C.
 Source:
 BioEssays 2019 v.41 no.6 pp. e1900027
 ISSN:
 02659247
 Subject:
 mathematics, etc ; biodiversity; biosphere; evolution; genetics; Show all 5 Subjects
 Abstract:
 ... Parrondo's paradox, in which losing strategies can be combined to produce winning outcomes, has received much attention in mathematics and the physical sciences; a plethora of exciting applications has also been found in biology at an astounding pace. In this review paper, the authors examine a large range of recent developments of Parrondo's paradox in biology, across ecology and evolution, genet ...
 DOI:
 10.1002/bies.201900027

http://dx.doi.org/10.1002/bies.201900027
 Author:
 Chieffi, Sergio; Castaldi, Clara; Di Maio, Girolamo; La Marra, Marco; Messina, Antonietta; Monda, Vincenzo; Villano, Ines
 Source:
 Comptes rendus 2019 v.342 no.34 pp. 97100
 ISSN:
 16310691
 Subject:
 mathematics and statistics, etc ; cognition; humans; Show all 3 Subjects
 Abstract:
 ... Under visual guidance, healthy subjects usually misbisect radial lines farther than, and vertical lines above the true center. It was suggested that radial and vertical misbisection depended on the presence of an attentional bias toward far/upper space. The aim of the present study was to investigate whether such attentional bias depends on a single mechanism or on separate mechanisms. Ninety part ...
 DOI:
 10.1016/j.crvi.2019.03.003

https://dx.doi.org/10.1016/j.crvi.2019.03.003
 Author:
 Notov, A. A.; Zhukova, L. A.
 Source:
 Biology bulletin of the Russian Academy of Sciences 2019 v.46 no.1 pp. 4755
 ISSN:
 10623590
 Subject:
 mathematics and statistics, etc ; ontogeny; phenotype; Show all 3 Subjects
 Abstract:
 ... The possibilities of using the concept of ontogeny polyvariance in evolutionary morphology are considered. The concept is aimed at identifying the full range of options associated with various aspects concerning the organization of living organisms. In conjunction with the analysis of the correlation structure of traits and methods of population meronomy, the proposed approach can help to elucidat ...
 DOI:
 10.1134/S1062359019010072

http://dx.doi.org/10.1134/S1062359019010072
 Author:
 Zeriouh, Mostafa; Ziane, M’hammed; Abdelalim, Seddik; Essanouni, Hassane
 Source:
 Journal of Taibah University for Science 2015 v.9 no.3 pp. 357360
 ISSN:
 16583655
 Subject:
 mathematics
 Abstract:
 ... In this paper, we show that if an automorphism α of an abelian torsion group, which is in fact a direct sum of its pcomponents, has the weak extension property then α=πidAp+ρ, where p is a prime number, π is an invertible padic number and ρ∈Hom(Ap,Ap1) with Ap1 is the first Ulm subgroup of the pcomponent Ap of A. ...
 DOI:
 10.1016/j.jtusci.2015.02.009

https://dx.doi.org/10.1016/j.jtusci.2015.02.009
 Author:
 Chellali, Mustapha
 Source:
 Journal of Taibah University for Science 2015 v.9 no.3 pp. 351356
 ISSN:
 16583655
 Subject:
 mathematics
 Abstract:
 ... Let K be a field and P∈K[X] is a polynomial of degree n, then the conjecture of CasasAlvero states that if P is not prime with each of its n−1 first derivatives, then it is a monomial, i.e., of the form c(X−r)n. We consider the case where K=ℝ and P is split over ℝ, where we show that the number un of hypothetical counterexamples of degree n satisfies (n−4)!≤un≤c(n−3)n−2, where c=2e−1(∏n=2∞e−1(∑k= ...
 DOI:
 10.1016/j.jtusci.2015.02.008

https://dx.doi.org/10.1016/j.jtusci.2015.02.008
 Author:
 Bamerni, Nareen; Kılıçman, Adem
 Source:
 Journal of Taibah University for Science 2015 v.9 no.3 pp. 414419
 ISSN:
 16583655
 Subject:
 mathematics
 Abstract:
 ... In this paper, we prove that if T is a diskcyclic operator then the closed unit disk multiplied by the union of the numerical range of all iterations of T is dense in H. Also, if T is a diskcyclic operator and λ≤1, then T−λI has dense range. Moreover, we prove that if α>1, then 1αT is hypercyclic in a separable Hilbert space H if and only if T⊕αIℂ is diskcyclic in H⊕ℂ. We show at least in some c ...
 DOI:
 10.1016/j.jtusci.2015.02.020

https://dx.doi.org/10.1016/j.jtusci.2015.02.020
 Author:
 Bahaa, G.M.; ElMarouf, S.A.A.; Embaby, O.A.
 Source:
 Journal of Taibah University for Science 2015 v.9 no.2 pp. 264273
 ISSN:
 16583655
 Subject:
 mathematics
 Abstract:
 ... A distributed Pareto optimal control problem for an infinite order parabolic system is considered. The performance index has a vector form with two components in integral form. Constraints on controls and on states are imposed. To obtain optimality conditions for the Neumann problem, the generalization of the Dubovitskii–Milyutin theorem was applied. ...
 DOI:
 10.1016/j.jtusci.2014.09.002

https://dx.doi.org/10.1016/j.jtusci.2014.09.002
 Author:
 Naduvath, Sudev; Chandoor, Susanth; Kalayathankal, Sunny Joseph; Kok, Johan
 Source:
 National Academy science letters 2019 v.42 no.3 pp. 249252
 ISSN:
 0250541X
 Subject:
 mathematics, etc ; color; data analysis; equations; graphs; Show all 5 Subjects
 Abstract:
 ... A rainbow neighbourhood of a graph G is the closed neighbourhood N[v] of a vertex [Formula: see text] which contains at least one coloured vertex of each colour in the chromatic colouring [Formula: see text] of G. Let G be a graph with a chromatic colouring [Formula: see text] defined on it. The number of vertices in G yielding rainbow neighbourhoods is called the rainbow neighbourhood number of t ...
 DOI:
 10.1007/s4000901807400

https://dx.doi.org/10.1007/s4000901807400
 Author:
 Ashida, Yoichiro; Wakitani, Shin; Yamamoto, Toru
 Source:
 Industrial & engineering chemistry process design and development 2019 v.58 no.26 pp. 1147411484
 ISSN:
 15205045
 Subject:
 mathematics, etc ; chemistry; data collection; process design; Show all 4 Subjects
 Abstract:
 ... Since the control performance of a proportional–integral–derivative (PID) control systems strongly depends on PID gains, lots of schemes for tuning PID gains have been proposed up to now. Recently, datadriven PID tuning schemes whose PID gains are directly determined from the closedloop operating data attract attention. Lots of controlled objects are multiinput/multioutput systems, though almo ...
 DOI:
 10.1021/acs.iecr.8b06118

http://dx.doi.org/10.1021/acs.iecr.8b06118
 Author:
 Liu, Chuanping; Wan, Hongmei; Wang, Li
 Source:
 Powder technology 2019 v.344 pp. 545550
 ISSN:
 00325910
 Subject:
 mathematics and statistics, etc ; granules; gravity; powders; Show all 4 Subjects
 Abstract:
 ... In this study, a cylinder is horizontally immersed in granular media and moved toward different directions. The cylinder experiences a maximum force (Fm) when plunging downward and a minimum force when pulling upward. As the cylinder moves angularly, the force (F) gradually decreases with increasing angle between the cylinder movement direction and gravity (θ). F/Fm behaves similar to a Boltzmann ...
 DOI:
 10.1016/j.powtec.2018.12.023

https://dx.doi.org/10.1016/j.powtec.2018.12.023