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Journal articles on the topic 'Four-vector derivative'

Author: Grafiati

Published: 3 June 2025

Last updated: 31 July 2025

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1

RESENDES, D. P. "Geometric algebra in plasma electrodynamics." Journal of Plasma Physics 79, no. 5 (2013): 735–38. http://dx.doi.org/10.1017/s0022377813000366.

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AbstractGeometric algebra (GA) is a recent broad mathematical framework incorporating synthetic and coordinate geometry, complex variables, quarternions, vector analysis, matrix algebra, spinors, tensors, and differential forms. It has been claimed to be a unified language for physics. GA is presented in the context of the Maxwell-Plasma system. In this formalism the divergence and curl differential operators are united in a single vector derivative, which is invertible, in the form of a first-order Green function. The four Maxwell equations can be combined into a single equation (for homogene

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2

Vo, Duc, Son Huynh, Anh Vo, and Dao Ha. "The Importance of the Financial Derivatives Markets to Economic Development in the World’s Four Major Economies." Journal of Risk and Financial Management 12, no. 1 (2019): 35. http://dx.doi.org/10.3390/jrfm12010035.

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Over the past three decades, China and India have attained economic power close to that of Japan and the U.S. During this period, the importance of the derivatives market within the financial market has been widely recognized. However, little supporting evidence is available on its economic effects. This paper investigates the dynamic relationship between the derivatives markets and economic development in these four large economies, which we consider together as the CIJU (China, India, Japan, and the U.S.) group. We use a Granger-causality test in the framework of a vector error correction mo

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Souza, Talita Evelyn, Iara Maria Landre Rosa, Alexandre Oliveira Legendre, et al. "Non-centrosymmetric crystals of newN-benzylideneaniline derivatives as potential materials for non-linear optics." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 71, no. 4 (2015): 416–26. http://dx.doi.org/10.1107/s2052520615008859.

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Three newN-benzylideneaniline derivatives [p-nitrobenzylidene-p-phenylamineaniline (I), 2,4-dinitrobenzylidene-p-phenylamineaniline (II) andp-dinitrobenzylidene-p-diethylamineaniline (III)] containing electron–push–pull groups have been prepared. They present a planarN-benzylideneaniline core and neighbouring functional atoms, which are related through an efficient intramolecular charge transfer (CT). Two of the derivatives crystallize in non-centrosymmetric space groups, a necessary condition for non-linear optical (NLO) responses. The NLO properties were calculated for the molecular conforma

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4

Badi, Hassan, Alina-Mihaela Patriciu, and Karim El Moutaouakil. "Fractional Intuitionistic Fuzzy Support Vector Machine: Diabetes Tweet Classification." Information 15, no. 11 (2024): 737. http://dx.doi.org/10.3390/info15110737.

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Support vector machine (SVM) models apply the Karush–Kuhn–Tucker (KKT-OC) optimality conditions in the ordinary derivative to the primal optimisation problem, which has a major influence on the weights associated with the dissimilarity between the selected support vectors and subsequently on the quality of the model’s predictions. Recognising the capacity of fractional derivatives to provide machine learning models with more memory through more microscopic differentiations, in this paper we generalise KKT-OC based on ordinary derivatives to KKT-OC using fractional derivatives (Frac-KKT-OC). To

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CHAVES, M., and H. MORALES. "UNIFICATION OF SU(2)⊗U(1) USING A GENERALIZED COVARIANT DERIVATIVE AND U(3)." Modern Physics Letters A 13, no. 25 (1998): 2021–33. http://dx.doi.org/10.1142/s0217732398002126.

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A generalization of the Yang–Mills covariant derivative, that uses both vector and scalar fields and transforms as a four-vector contracted with Dirac matrices, is used to simplify the Glashow–Weinberg–Salam model. Since SU(3) assigns the wrong hypercharge to the Higgs boson, it is necessary to use a special representation of U(3) to obtain all the correct quantum numbers. A surplus gauge scalar boson emerges in the process, but it uncouples from all other particles.

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Quadri, Andrea. "Decoupling Limits in Effective Field Theories via Higher Dimensional Operators." Universe 10, no. 2 (2024): 85. http://dx.doi.org/10.3390/universe10020085.

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The non-decoupling effects of heavy scalars and vector fields play an important role in the indirect search for Beyond the Standard Model (BSM) physics at the LHC. By exploiting some new differential equations for the 1-PI amplitudes, we show that such non-decoupling effects are absent for quite a general class of effective field theories involving dimension six two-derivative and dimension eight four-derivative operators, once the resummation in certain BSM couplings is taken into account and some particular regimes of the relevant couplings are considered.

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7

Palermo, Andrea, Francesco Becattini, Matteo Buzzegoli, Gabriele Inghirami, and Iurii Karpenko. "Local equilibrium and Lambda polarization in high energy heavy ion collisions." EPJ Web of Conferences 276 (2023): 01026. http://dx.doi.org/10.1051/epjconf/202327601026.

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The polarization of the Λ hyperon has become an important probe of the Quark-Gluon Plasma produced in relativistic heavy-ion collisions. Recently, it has been found that polarization receives a substantial contribution from a local equilibrium term proportional to the symmetric derivative of the four-temperature vector, the thermal shear tensor. We show that, at very high energies, this term can restore the agreement between the experimental measurements and the predictions of the hydrodynamic model, provided that the hadronization hypersurface is isothermal. We review the theoretical derivati

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Tong, Yu, Wenzhe Zhang, Xi Qin, Yijin Xie, Xing Rong, and Jiangfeng Du. "A customized control and readout device for vector magnetometers based on nitrogen-vacancy centers." Review of Scientific Instruments 94, no. 1 (2023): 014709. http://dx.doi.org/10.1063/5.0132545.

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A customized control and readout device, which is developed to perform real-time measurement for vector magnetometers based on nitrogen-vacancy centers, is presented in this paper. A dual-channel analog-to-digital-converter chip, which has a 25 MSa/s sampling rate and a 16 bits amplitude resolution, is integrated for analog signal acquisition. The data processing and the system control are realized using a Xilinx Kirtex-7 field-programmable-gate-array chip. Eight independent lock-in modules, a four-channel proportional–integral–derivative controller, a reference generator, and a vector field r

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9

West, Peter. "On the different formulations of the E11 equations of motion." Modern Physics Letters A 32, no. 18 (2017): 1750096. http://dx.doi.org/10.1142/s0217732317500961.

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The nonlinear realization of the semi-direct product of [Formula: see text] with its vector representation leads to equation of motions for the field graviton, three-form, six-form, dual graviton and the level four fields which correctly describe the degree of freedom of 11-dimensional supergravity at the linearized level. The equations with one derivative generically hold as equivalence relations and are often duality relations. From these equations, by taking derivatives, one can derive equations that are equations of motion of the familiar kind. The entire hierarchy of equations is [Formula

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10

Ottnad, Konstantin, Tim Harris, Harvey Meyer, Georg von Hippel, Jonas Wilhelm, and Hartmut Wittig. "Nucleon average quark momentum fraction with Nf = 2+1 Wilson fermions." EPJ Web of Conferences 175 (2018): 06026. http://dx.doi.org/10.1051/epjconf/201817506026.

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We report on an analysis of the average quark momentum fraction of the nucleon and related quantities using Nf = 2 + 1 Wilson fermions. Computations are performed on four CLS ensembles covering three values of the lattice spacing at pion masses down to Mπ ≈ 200 MeV. Several source-sink separations (~ 1:0 fm to ~ 1:4 fm) are used to assess the excited-state contamination. To gain further insight, the generalized pencil-of-functions approach has been implemented to reduce the excited-state contamination in the relevant two-and three-point functions. Preliminary results are shown for the isovecto

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Otalora, Giovanni. "A novel teleparallel dark energy model." International Journal of Modern Physics D 25, no. 02 (2016): 1650025. http://dx.doi.org/10.1142/s0218271816500255.

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Although equivalent to general relativity, teleparallel gravity (TG) is conceptually speaking a completely different theory. In this theory, the gravitational field is described by torsion, not by curvature. By working in this context, a new model is proposed in which the four-derivative of a canonical scalar field representing dark energy is nonminimally coupled to the “vector torsion”. This type of coupling is motivated by the fact that a scalar field couples to torsion through its four-derivative, which is consistent with local spacetime kinematics regulated by the de Sitter group [Formula:

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12

Wang, Chuan Tang, Xiu Zhen Wang, Yue Yi Tang, et al. "Predicting Main Fatty Acids, Oil and Protein Content in Intact Single Seeds of Groundnut by near Infrared Reflectance Spectroscopy." Advanced Materials Research 860-863 (December 2013): 490–96. http://dx.doi.org/10.4028/www.scientific.net/amr.860-863.490.

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Eighty-four, 61 and 105 groundnut seeds, including high oleate genotypes and F2 seeds of normal oleate × high oleate crosses, genotypes with high or low oil and F2 seeds from high oil × low oil crosses, and randomly selected samples representing various origins, different seed sizes, and varied seed coat color and protein content, were used to develop the NIRS models for main fatty acids, oil and protein. For oleic, linoleic and palmitic acid, the optimized spectrum pretreatment method was first derivative plus multiplicative scattering correction; for stearic acid and the four bad fatty acids

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13

Rosales Luengas, Yukio, Ricardo López-Gutiérrez, Sergio Salazar, and Rogelio Lozano. "Robust controls for upper limb exoskeleton, real-time results." Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 232, no. 7 (2018): 797–806. http://dx.doi.org/10.1177/0959651818758866.

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This article shows the development of an exoskeleton for human joint. The exoskeleton proposed was developed for rehabilitating individuals who have suffered injuries at their shoulders, by rehabilitation exercises. The exoskeleton has special characteristics to deal with the 5 degrees of freedom of the human shoulder. The dynamic model results in the following form: [Formula: see text], where [Formula: see text] and [Formula: see text] are state’s vector, torque’s vector, a matrix function and a vector function, respectively. Therefore, we applied four different control laws, among which stan

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14

Balakin, Alexander B., and Amir F. Shakirzyanov. "Is the Axionic Dark Matter an Equilibrium System?" Universe 6, no. 11 (2020): 192. http://dx.doi.org/10.3390/universe6110192.

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We consider an axionic dark matter model with a modified periodic potential for the pseudoscalar field in the framework of the axionic extension of the Einstein-aether theory. The modified potential is assumed to be equipped by the guiding function, which depends on the expansion scalar constructed as the trace of the covariant derivative of the aether velocity four-vector. The equilibrium state of the axion field is defined as the state, for which the modified potential itself and its first derivative with respect to the pseudoscalar field are equal to zero. We apply the developed formalism t

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15

Fiorenza, Alberto, and Renato Fiorenza. "Generalizations of Rolle’s Theorem." Mathematics 12, no. 14 (2024): 2157. http://dx.doi.org/10.3390/math12142157.

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The classical Rolle’s theorem establishes the existence of (at least) one zero of the derivative of a continuous one-variable function on a compact interval in the real line, which attains the same value at the extremes, and it is differentiable in the interior of the interval. In this paper, we generalize the statement in four ways. First, we provide a version for functions whose domain is in a locally convex topological Hausdorff vector space, which can possibly be infinite-dimensional. Then, we deal with the functions defined in a real interval: we consider the case of unbounded intervals,

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16

Chen, Pei Yun, Dong Jun Gong, Yan Ping Pang, Li Ya Xia, and Shao Long Yu. "Study on Identification Method of Banqiao Codonopsis Pilosulc with Near-Infrared Spectroscopy." Advanced Materials Research 955-959 (June 2014): 838–42. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.838.

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In order to identify the Banqiao codonopsis pilosulc, a geographical indication products,diffuse reflectance spectroscopy of came from four different origins were collected by the Fourier near-infrared spectrometer. The spectroscopy was analyzed with Chemometrics method,and the spectroscopy was pretreated by the second derivative and vector normalized, first derivation and minus a straight line condition. The range of spectra was 7637.3-4165.8 cm-1. The Calibration models of Codonopsis pilosulc were established by the qualification testing, principal component analysis, and cluster analysis re

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17

Ullrich, P. A. "A global finite-element shallow-water model supporting continuous and discontinuous elements." Geoscientific Model Development 7, no. 6 (2014): 3017–35. http://dx.doi.org/10.5194/gmd-7-3017-2014.

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Abstract. This paper presents a novel nodal finite-element method for either continuous and discontinuous elements, as applied to the 2-D shallow-water equations on the cubed sphere. The cornerstone of this method is the construction of a robust derivative operator that can be applied to compute discrete derivatives even over a discontinuous function space. A key advantage of the robust derivative is that it can be applied to partial differential equations in either a conservative or a non-conservative form. However, it is also shown that discontinuous penalization is required to recover the c

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18

Pan, Banglong, Hanming Yu, Hongwei Cheng, et al. "Machine Learning Model of Hydrothermal Vein Copper Deposits at Meso-Low Temperatures Based on Visible-Near Infrared Parallel Polarized Reflectance Spectroscopy." Minerals 12, no. 11 (2022): 1451. http://dx.doi.org/10.3390/min12111451.

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The verification efficiency and precision of copper ore grade has a great influence on copper ore mining. At present, the common method for the exploration of reserves often uses chemical analysis and identification, which have high costs, long cycles, and pollution risks but cannot realize the in situ determination of the copper grade. The existing scalar spectrometric techniques generally have limited accuracy. As a vector spectrum, polarization state information is sensitive to mineral particle distribution and composition, which is conducive to high-precision detection. Taking the visible-

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19

Zheng, Xiangqun H., and Stephen H. Hughes. "An Avian Sarcoma/Leukosis Virus-Based Gene Trap Vector for Mammalian Cells." Journal of Virology 73, no. 8 (1999): 6946–52. http://dx.doi.org/10.1128/jvi.73.8.6946-6952.1999.

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ABSTRACT RCASBP-M2C is a retroviral vector derived from an avian sarcoma/leukosis virus which has been modified so that it uses the envelope gene from an amphotropic murine leukemia virus (E. V. Barsov and S. H. Hughes, J. Virol. 70:3922–3929, 1996). The vector replicates efficiently in avian cells and infects, but does not replicate in, mammalian cells. This makes the vector useful for gene delivery, mutagenesis, and other applications in mammalian systems. Here we describe the development of a derivative of RCASBP-M2C, pGT-GFP, that can be used in gene trap experiments in mammalian cells. Th

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20

Gunara, Bobby Eka. "Curved Dyonic Domain Walls in Four Dimensions." INDONESIAN JOURNAL OF APPLIED PHYSICS 4, no. 01 (2016): 37. http://dx.doi.org/10.13057/ijap.v4i01.1164.

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<span>In this short paper we show the existence of solitonic solutions of four dimensional ungauged N=1 <span>supergravity coupled to arbitrary vector and chiral multiplets whose Ricci scalar curvature is constant. <span>The Ricci scalar of spacetimes indeed depends on the <span><em>σ</em><span>-model, namely the complex scalars and their first <span>derivative. Then, we give two explicit models, namely static domain walls and static spherical symmetric <span>black holes which are related to our previous works.</span></span><

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Li, B. A., and Y. L. Wu. "Hidden Local Symmetry and Effective Chiral Theory for Vector and Axial-vector Mesons." Modern Physics Letters A 22, no. 07n10 (2007): 683–98. http://dx.doi.org/10.1142/s0217732307023286.

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We present the effective chiral Lagrangian of mesons (peusodoscalars, vectors and axial-vectors) obtained in the chiral limit by using two approaches. The first approach is based on symmetries: the explicit global chiral symmetry and hidden local chiral symmetry. In this approach, it is noticed that there are in general fourteen interacting terms up to the dimension-four of covariant derivative for meson fields rather than the usual eleven interacting terms given in literature from hidden local symmetry approach. Of particular, the additional terms are found to be very important for understand

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22

Wang, Changbiao. "von Laue’s theorem and its applications." Canadian Journal of Physics 93, no. 12 (2015): 1470–76. http://dx.doi.org/10.1139/cjp-2015-0198.

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von Laue’s theorem, as well as its generalized form, is strictly proved in detail for its sufficient and necessary condition (SNC). This SNC version of Laue’s theorem is used to analyze the infinitely extended electrostatic field produced by a charged metal sphere in free space, and the static field confined in a finite region of space. It is shown in general that the total (Abraham=Minkowski) electromagnetic momentum and energy for the electrostatic field cannot constitute a Lorentz four-vector. A derivative von Laue’s theorem, which provides a criterion for a Lorentz invariant, is also prese

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23

Alotaiby, Turky N., Fatima Aljabarti, Gaseb Alotibi, and Saleh A. Alshebeili. "A Nonfiducial PPG-Based Subject Authentication Approach Using the Statistical Features of DWT-Based Filtered Signals." Journal of Sensors 2020 (October 17, 2020): 1–14. http://dx.doi.org/10.1155/2020/8849845.

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Nowadays, there is a global change in lifestyle that is moving more toward the use of e-services and smart devices which necessitate the verification of user identity. Different organizations have put into place a range of technologies, hardware, and/or software to authenticate users using fingerprints, iris recognition, and so forth. However, cost and reliability are significant limitations to the use of such technologies. This study presents a nonfiducial PPG-based subject authentication system. In particular, the photoplethysmogram (PPG) signal is first filtered into four signals using the

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Fedosin, Sergey G. "Equations of Motion in the Theory of Relativistic Vector Fields." International Letters of Chemistry, Physics and Astronomy 83 (August 2019): 12–30. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.83.12.

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Within the framework of the theory of relativistic vector fields, the covariant expressions are presented for the equations of motion of the matter and the field. These expressions can be written either in terms of the field tensors, that is, the fields’ strengths and solenoidal vectors, or in terms the four-potentials, that is, the fields’ scalar and vector potentials. This state of things is due to the fact that the Lagrange function initially implied the complementarity of description in terms of the strengths and the field potentials. It is shown that the equation for the fields, obtained

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Fedosin, Sergey G. "Equations of Motion in the Theory of Relativistic Vector Fields." International Letters of Chemistry, Physics and Astronomy 83 (August 14, 2019): 12–30. http://dx.doi.org/10.56431/p-nq2116.

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Within the framework of the theory of relativistic vector fields, the covariant expressions are presented for the equations of motion of the matter and the field. These expressions can be written either in terms of the field tensors, that is, the fields’ strengths and solenoidal vectors, or in terms the four-potentials, that is, the fields’ scalar and vector potentials. This state of things is due to the fact that the Lagrange function initially implied the complementarity of description in terms of the strengths and the field potentials. It is shown that the equation for the fields, obtained

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26

Wada, Takaomi, Masafumi Noda, Fumi Kashiwabara, et al. "Characterization of four plasmids harboured in a Lactobacillus brevis strain encoding a novel bacteriocin, brevicin 925A, and construction of a shuttle vector for lactic acid bacteria and Escherichia coli." Microbiology 155, no. 5 (2009): 1726–37. http://dx.doi.org/10.1099/mic.0.022871-0.

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In this study we isolated over 250 lactic acid bacteria (LAB) candidates from fruit, flowers, vegetables and a fermented food to generate an LAB library. One strain, designated 925A, isolated from kimchi (a traditional Korean fermented dish made from Chinese cabbage) produced a novel type of bacteriocin, brevicin 925A, which is effective against certain LAB, including strains of Lactobacillus, Enterococcus, Streptococcus, Bacillus and Listeria. Strain 925A, identified as Lactobacillus brevis, harboured at least four plasmids and we determined the entire nucleotide sequence of each one. The fou

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27

Xie, Feng, Dongsheng Yang, Yao Yang, Tao Wang, and Kai Zhang. "Infrared Small Target Detection Using Directional Derivative Correlation Filtering and a Relative Intensity Contrast Measure." Remote Sensing 17, no. 11 (2025): 1921. https://doi.org/10.3390/rs17111921.

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Detecting small targets in infrared search and track (IRST) systems in complex backgrounds poses a significant challenge. This study introduces a novel detection framework that integrates directional derivative correlation filtering (DDCF) with a local relative intensity contrast measure (LRICM) to effectively handle diverse background disturbances, including cloud edges and structural corners. This approach involves converting the original infrared image into an infrared gradient vector field (IGVF) using a facet model. Exploiting the distinctive characteristics of small targets in second-ord

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Matiadis, Dimitris, Panagiota G. V. Liggri, Eftichia Kritsi, et al. "Curcumin Derivatives as Potential Mosquito Larvicidal Agents against Two Mosquito Vectors, Culex pipiens and Aedes albopictus." International Journal of Molecular Sciences 22, no. 16 (2021): 8915. http://dx.doi.org/10.3390/ijms22168915.

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Vector-borne diseases have appeared or re-emerged in many Southern Europe countries making the transmission of infectious diseases by mosquitoes (vectors) one of the greatest worldwide health threats. Larvicides have been used extensively for the control of Aedes (Stegomyia) albopictus (Skuse, 1895) (Diptera: Culicidae) and Culex pipiens Linnaeus, 1758 (Diptera: Culicidae) mosquitoes in urban and semi-urban environments, causing the increasing resistance of mosquitoes to commercial insecticides. In this study, 27 curcuminoids and monocarbonyl curcumin derivatives were synthesised and evaluated

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29

Liu, Jie, Xiao Yu Li, Wei Wang, and Jun Zhang. "Application of Support Vector Machine in Identifying inside Moldy Chestnut Using Near Infrared Spectroscopy." Applied Mechanics and Materials 615 (August 2014): 169–72. http://dx.doi.org/10.4028/www.scientific.net/amm.615.169.

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NIR spectroscopy has been applied in detecting inside quality of chestnut successfully. In this work, Support Vector Machine Discriminant Analysis was utilized to identify the qualified chestnuts, the serious moldy chestnuts and the slight moldy chestnuts using their Near infrared spectra region from 833 nm to 2500 nm. 109 chestnut samples were involved and four different preprocessing methods were compared. The results showed that for all the models, the average correct rates of training set and validation set were higher than 90%. The performance of model based on raw spectra was not as good

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Liu, Y. Y., H. S. Fu, J. B. Cao, C. X. Du, and W. Z. Zhang. "Maximum Aligned Directional Derivative (MADD) Technique for Planar Structure Analysis in Space." Astrophysical Journal Supplement Series 270, no. 1 (2023): 6. http://dx.doi.org/10.3847/1538-4365/ad077c.

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Abstract Interplanetary discontinuities are the most common intermittent structures in the solar winds, whose jump conditions conform to the Rankine–Hugoniot relations. The identification and analysis of such planar structures rely on an accurate determination of the normal vectors. In this study, we perform a benchmark test of a technique designed to estimate the dimensionality and orientation of the magnetic fields based on four spacecraft measurements. Such a technique operates on the fact that in a strictly planar magnetic field, three columns of ∇ B are all aligned and the characteristic

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Fedosin, Sergey G. "Equations of Motion in the Theory of Relativistic Vector Fields." International Letters of Chemistry, Physics and Astronomy 83 (October 8, 2019): 12–30. https://doi.org/10.18052/www.scipress.com/ILCPA.83.12.

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Within the framework of the theory of relativistic vector fields, the covariant expressions are presented for the equations of motion of the matter and the field. These expressions can be written either in terms of the field tensors, that is, the fields’ strengths and solenoidal vectors, or in terms the four-potentials, that is, the fields’ scalar and vector potentials. This state of things is due to the fact that the Lagrange function initially implied the complementarity of description in terms of the strengths and the field potentials. It is shown that the equation for the field

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32

ESPOSITO, GIAMPIERO, and GIUSEPPE POLLIFRONE. "TWISTORS IN CONFORMALLY FLAT EINSTEIN FOUR-MANIFOLDS." International Journal of Modern Physics D 05, no. 05 (1996): 481–93. http://dx.doi.org/10.1142/s0218271896000291.

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This paper studies the two-component spinor form of massive spin-[Formula: see text] potentials in conformally flat Einstein four-manifolds. Following earlier work in the literature, a nonvanishing cosmological constant makes it necessary to introduce a supercovariant derivative operator. The analysis of supergauge transformations of primary and secondary potentials for spin-[Formula: see text] shows that the gauge freedom for massive spin-[Formula: see text] potentials is generated by solutions of the supertwistor equations. The supercovariant form of a partial connection on a nonlinear bundl

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Zhang, Sen, Xia Lu, Yuanzhi Zhang, Gege Nie, and Yurong Li. "Estimation of Soil Organic Matter, Total Nitrogen and Total Carbon in Sustainable Coastal Wetlands." Sustainability 11, no. 3 (2019): 667. http://dx.doi.org/10.3390/su11030667.

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Soil plays an important role in coastal wetland ecosystems. The estimation of soil organic matter (SOM), total nitrogen (TN), and total carbon (TC) was investigated at the topsoil (0–20 cm) in the coastal wetlands of Dafeng Elk National Nature Reserve in Yancheng, Jiangsu province (China) using hyperspectral remote sensing data. The sensitive bands corresponding to SOM, TN, and TC content were retrieved based on the correlation coefficient after Savitzky–Golay (S–G) filtering and four differential transformations of the first derivative (R′), first derivative of reciprocal (1/R)′, second deriv

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Shubov, Marianna A. "Location of eigenmodes of Euler–Bernoulli beam model under fully non-dissipative boundary conditions." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 475, no. 2231 (2019): 20190544. http://dx.doi.org/10.1098/rspa.2019.0544.

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The Euler–Bernoulli beam model with non-conservative feedback-type boundary conditions is investigated. Components of the two-dimensional input vector are shear and moment at the right end, and components of the observation vector are time derivative of displacement and slope at the right end. The boundary matrix containing four control parameters relates input and observation. The following results are presented: (i) if one and only one of the control parameters is positive and the rest of them are equal to zero, then the set of the eigenmodes is located in the open left half-plane of the com

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Phuong, Bui Thi Lan Phuong, Hoang Thi Bich, Nguyen Van Phuong, et al. "GEOGRAPHICAL DISCRIMINANT AND CLASSIFICATION OF CINNAMOMUM CASSIA COLLECTED IN VIETNAM USING ATR-FTIR COUPLED WITH MACHINE LEARNING ALGORITHMS." ChemChemTech 68, no. 7 (2025): 102–13. https://doi.org/10.6060/ivkkt.20256807.7246.

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In Vietnam, Cinnamomum cassia is widely utilized not only as a spice but also as a key ingredient in medicine, cosmetics, and the processing industry. The varying climatic conditions across different geographic regions where cinnamon is cultivated significantly influence its quality, often leading to the unintentional mixing of cinnamon from multiple sources. To analyze cinnamon samples, Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR) was employed to measure 139 samples collected from four distinct provinces in Vietnam – Yen Bai, Quang Ninh, Thanh Hoa, and Quang

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Islam, Tanvir Tazul, Md Sajid Ahmed, Md Hassanuzzaman, Syed Athar Bin Amir, and Tanzilur Rahman. "Blood Glucose Level Regression for Smartphone PPG Signals Using Machine Learning." Applied Sciences 11, no. 2 (2021): 618. http://dx.doi.org/10.3390/app11020618.

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Diabetes is a chronic illness that affects millions of people worldwide and requires regular monitoring of a patient’s blood glucose level. Currently, blood glucose is monitored by a minimally invasive process where a small droplet of blood is extracted and passed to a glucometer—however, this process is uncomfortable for the patient. In this paper, a smartphone video-based noninvasive technique is proposed for the quantitative estimation of glucose levels in the blood. The videos are collected steadily from the tip of the subject’s finger using smartphone cameras and subsequently converted in

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Islam, Tanvir Tazul, Md Sajid Ahmed, Md Hassanuzzaman, Syed Athar Bin Amir, and Tanzilur Rahman. "Blood Glucose Level Regression for Smartphone PPG Signals Using Machine Learning." Applied Sciences 11, no. 2 (2021): 618. http://dx.doi.org/10.3390/app11020618.

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Diabetes is a chronic illness that affects millions of people worldwide and requires regular monitoring of a patient’s blood glucose level. Currently, blood glucose is monitored by a minimally invasive process where a small droplet of blood is extracted and passed to a glucometer—however, this process is uncomfortable for the patient. In this paper, a smartphone video-based noninvasive technique is proposed for the quantitative estimation of glucose levels in the blood. The videos are collected steadily from the tip of the subject’s finger using smartphone cameras and subsequently converted in

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Weng, Zi-Hua. "Forces in the complex octonion curved space." International Journal of Geometric Methods in Modern Physics 13, no. 06 (2016): 1650076. http://dx.doi.org/10.1142/s0219887816500766.

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The paper aims to extend major equations in the electromagnetic and gravitational theories from the flat space into the complex octonion curved space. Maxwell applied simultaneously the quaternion analysis and vector terminology to describe the electromagnetic theory. It inspires subsequent scholars to study the electromagnetic and gravitational theories with the complex quaternions/octonions. Furthermore Einstein was the first to depict the gravitational theory by means of tensor analysis and curved four-space–time. Nowadays some scholars investigate the electromagnetic and gravitational prop

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Zhou, Zhu, Sohrab Rahimi, Stavros Avramidis, and Yiming Fang. "Species- and moisture-based sorting of green timber mix with near infrared spectroscopy." BioResources 15, no. 1 (2019): 317–30. http://dx.doi.org/10.15376/biores.15.1.317-330.

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Methods suitable for the determination and classification of green timber mix (western hemlock and amabilis fir), with respect to species and moisture content, were developed and tested using near infrared spectroscopy and chemometrics. One thousand two hundred samples were distributed into a calibration set (720 samples) and a prediction set (480 samples). Partial least squares (PLS) and least squares-support vector machines (LS-SVM) for both regression (PLSR and LS-SVR) and classification (PLS-DA and LS-SVC) with different spectral preprocessing methods were implemented. LS-SVM outperformed

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Pérez-Pantoja, D., L. Guzmán, M. Manzano, D. H. Pieper, and B. González. "Role oftfdCIDIEIFIandtfdDIICIIEIIFIIGene Modules in Catabolism of 3-Chlorobenzoate by Ralstonia eutropha JMP134(pJP4)." Applied and Environmental Microbiology 66, no. 4 (2000): 1602–8. http://dx.doi.org/10.1128/aem.66.4.1602-1608.2000.

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ABSTRACT The enzymes chlorocatechol-1,2-dioxygenase, chloromuconate cycloisomerase, dienelactone hydrolase, and maleylacetate reductase allow Ralstonia eutropha JMP134(pJP4) to degrade chlorocatechols formed during growth in 2,4-dichlorophenoxyacetate or 3-chlorobenzoate (3-CB). There are two gene modules located in plasmid pJP4,tfdCIDIEIFI (module I) andtfdDIICIIEIIFII (module II), putatively encoding these enzymes. To assess the role of both tfd modules in the degradation of chloroaromatics, each module was cloned into the medium-copy-number plasmid vector pBBR1MCS-2 under the control of the

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ROBERTS, C. D., J. PRASCHIFKA, and R. T. CAHILL. "A CHIRALLY SYMMETRIC EFFECTIVE ACTION FOR VECTOR AND AXIAL VECTOR FIELDS IN A GLOBAL COLOR SYMMETRY MODEL OF QCD." International Journal of Modern Physics A 04, no. 07 (1989): 1681–733. http://dx.doi.org/10.1142/s0217751x89000674.

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We consider the quantum field theory of a model of an extended Nambu-Jona-Lasinio type with a QCD based nonlocal fermion current-current interaction which has global SU(Nc) symmetry. We obtain an exact bosonization of this model in four Euclidean dimensions using auxiliary bilocal fields and discuss the dynamical breakdown of chiral symmetry in the massless fermion limit. A local field bosonization is obtained by decomposing the bilocal fields in terms of complete orthonormal sets of functions with the expansion coefficients, which are local functions, identified as the local meson fields. Ret

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Abdelwanis, Mohamed I., Fayez F. M. El-Sousy, and Mosaad M. Ali. "A Fuzzy-Based Proportional–Integral–Derivative with Space-Vector Control and Direct Thrust Control for a Linear Induction Motor." Electronics 12, no. 24 (2023): 4955. http://dx.doi.org/10.3390/electronics12244955.

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In this study, the analysis and control of a multi-phase linear induction motor loaded with a variable mechanical system are carried out. Mathematical models are established, and simulation results are analyzed for an improved proportional–integral–derivative controller with closed-loop vector control for PLIM. To make the PID controller more responsive to load thrust disturbances, a fuzzy PID load thrust observer was developed. The FPID is similarly based on space-vector modulation DTC technology to regulate the PLIM’s speed, flux, and thrust. The FPID output is used to calculate the referenc

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Kivanc, Omer, and Salih Ozturk. "Low-Cost Position Sensorless Speed Control of PMSM Drive Using Four-Switch Inverter." Energies 12, no. 4 (2019): 741. http://dx.doi.org/10.3390/en12040741.

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A low-cost position sensorless speed control method for permanent magnet synchronous motors (PMSMs) is proposed using a space vector PWM based four-switch three-phase (FSTP) inverter. The stator feedforward d q -axes voltages are obtained for the position sensorless PMSM drive. The q-axis current controller output with a first order low-pass filter formulates the rotor speed estimation algorithm in a closed-loop fashion similar to PLL (Phase Lock Loop) and the output of the d-axis current controller acts as the derivative representation in the stator feedforward voltage equation. The proposed

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Abdelwanis, Mohamed I., and Ragab A. El-Sehiemy. "Performance enhancement of split-phase induction motor by using fuzzy-based PID controller." Journal of Electrical Engineering 70, no. 2 (2019): 103–12. http://dx.doi.org/10.2478/jee-2019-0016.

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Abstract This paper presents control and analysis of a split-phase induction motor (SPIM) to drive a centrifugal pumping system. An optimized proportional- integral and derivative (PID) controller, that is capable with a vector closed-loop split-phase induction motor control, is presented and its simulation results are discussed. The fine-tuning procedure is employed for fuzzy PID (FPID) controller parameters in order to sustain the motor speed at the predefined reference values. To assess the performance of the competitive controllers, conventional PID (CPID) and FPID, four operational indice

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Balakin, Alexander, Alexei Ilin, Anna Kotanjyan, and Levon Grigoryan. "Relativistic Neutron Stars: Rheological Type Extensions of the Equations of State." Symmetry 11, no. 2 (2019): 189. http://dx.doi.org/10.3390/sym11020189.

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Based on the Rheological Paradigm, we extend the equations of state for relativistic spherically symmetric static neutron stars, taking into consideration the derivative of the matter pressure along the so-called director four-vector. The modified equations of state are applied to the model of a zero-temperature neutron condensate. This model includes one new parameter with the dimensionality of length, which describes the rheological type screening inside the neutron star. As an illustration of the new approach, we consider the rheological type generalization of the non-relativistic Lane–Emde

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Dorsey, Caleb W., Andrew P. Tomaras, and Luis A. Actis. "Genetic and Phenotypic Analysis of Acinetobacter baumannii Insertion Derivatives Generated with a Transposome System." Applied and Environmental Microbiology 68, no. 12 (2002): 6353–60. http://dx.doi.org/10.1128/aem.68.12.6353-6360.2002.

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ABSTRACT Acinetobacter baumannii is a metabolically versatile pathogen that causes severe infections in compromised patients. However, little is known about the genes and factors involved in its basic physiology and virulence properties. Insertion mutagenesis was used to initiate the identification and characterization of some of these factors and genes in the prototype strain 19606. The utilization of the pLOFKm suicide delivery vector, which harbors a suicide mini-Tn10 derivative, proved to be unsuccessful for this purpose. The EZ::TN 〈R6Kγori/KAN-2〉 Tnp transposome system available from Epi

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Fu, Mingyu, Lijing Dong, Yujie Xu, and Chenglong Wang. "Adaptive Trajectory Tracking Safety Control of Air Cushion Vehicle with Unknown Input Effective Parameters." Applied Sciences 10, no. 16 (2020): 5695. http://dx.doi.org/10.3390/app10165695.

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This paper studies the trajectory tracking control problem of an Air Cushion Vehicle (ACV) with yaw rate error constraint, input effective parameters, model uncertainties and external wind disturbance. Firstly, based on the four-degree of freedom (DOF) vector mathematical mode of ACV, the radial basis function neural network (RBFNN) is adopted to provide the estimation of model uncertainties and external wind disturbance. Then, an adaptive Nussbaum gain-based approach is incorporated with the backstepping control scheme to handle the unknown input efficient parameters. To avoid the complicated

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Maqsood, M., H. A. Habib, S. M. Anwar, M. A. Ghazanfar, and T. Nawaz. "A Comparative Study of Classifier Based Mispronunciation Detection System for Confusing." Nucleus 54, no. 2 (2017): 114–20. https://doi.org/10.71330/thenucleus.2017.70.

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Pronunciation training systems detect mispronunciations from language learner’s speech and provide useful feedback. Mispronunciation detection systems can either be developed using Confidence Measures (CM) or using classifiers with Acoustic Phonetic Features (APF). This paper presents an APF based computer assisted pronunciation training (CAPT) system for most confusing Arabic phoneme pairs (/ ? / vs/ ?/)and (/ ? / vs / ? / or / ? /) developed for subjects of Pakistani origin. A super-vector is formed based on APF consisting of Mel-frequency cepstral coefficients (MFCCs) along with its first a

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Barker, Clive S., Birgit M. Prüß, and Philip Matsumura. "Increased Motility of Escherichia coli by Insertion Sequence Element Integration into the Regulatory Region of the flhD Operon." Journal of Bacteriology 186, no. 22 (2004): 7529–37. http://dx.doi.org/10.1128/jb.186.22.7529-7537.2004.

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ABSTRACT The flhD operon is the master operon of the flagellar regulon and a global regulator of metabolism. The genome sequence of the Escherichia coli K-12 strain MG1655 contained an IS1 insertion sequence element in the regulatory region of the flhD promoter. Another stock of MG1655 was obtained from the E. coli Genetic Stock Center. This stock contained isolates which were poorly motile and had no IS1 element upstream of the flhD promoter. From these isolates, motile subpopulations were identified after extended incubation in motility agar. Purified motile derivatives contained an IS5 elem

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Cao, Jingjing, Kai Liu, Yuanhui Zhu, Jun Li, and Zhi He. "Identifying Mangrove Species Using Field Close-Range Snapshot Hyperspectral Imaging and Machine-Learning Techniques." Remote Sensing 10, no. 12 (2018): 2047. http://dx.doi.org/10.3390/rs10122047.

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Investigating mangrove species composition is a basic and important topic in wetland management and conservation. This study aims to explore the potential of close-range hyperspectral imaging with a snapshot hyperspectral sensor for identifying mangrove species under field conditions. Specifically, we assessed the data pre-processing and transformation, waveband selection and machine-learning techniques to develop an optimal classification scheme for eight mangrove species in Qi'ao Island of Zhuhai, Guangdong, China. After data pre-processing and transformation, five spectral datasets, which i

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