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81.
A variant of Simulated Annealing termed Simulated Annealing with Multiplicative Weights (SAMW) has been proposed in the literature. However, convergence was dependent on a parameter β(T), which was calculated a-priori based on the total iterations T the algorithm would run for. We first show the convergence of SAMW even when a diminishing stepsize βk → 1 is used, where k is the index of iteration. Using this SAMW as a kernel, a stochastic multi-armed bandit (SMAB) algorithm called SOFTMIX can be improved to obtain the minimum-possible log regret, as compared to log2 regret of the original. Another modification of SOFTMIX is proposed which avoids the need for a parameter that is dependent on the reward distribution of the arms. Further, a variant of SOFTMIX that uses a comparison term drawn from another popular SMAB algorithm called UCB1 is then described. It is also shown why the proposed scheme is computationally more efficient over UCB1, and an alternative to this algorithm with simpler stepsizes is also proposed. Numerical simulations for all the proposed algorithms are then presented. 相似文献
82.
Stephen C. Anco Shahid Mohammad Thomas Wolf Chunrong Zhu 《Journal of Nonlinear Mathematical Physics》2016,23(4):573-606
A one-parameter generalization of the hierarchy of negative flows is introduced for integrable hierarchies of evolution equations, which yields a wider (new) class of non-evolutionary integrable nonlinear wave equations. As main results, several integrability properties of these generalized negative flow equation are established, including their symmetry structure, conservation laws, and bi-Hamiltonian formulation. (The results also apply to the hierarchy of ordinary negative flows). The first generalized negative flow equation is worked out explicitly for each of the following integrable equations: Burgers, Korteweg-de Vries, modified Korteweg-de Vries, Sawada-Kotera, Kaup-Kupershmidt, Kupershmidt. 相似文献
83.
84.
This paper presents a simple, specific, and precise high-performance liquid chromatographic method for the simultaneous determination of paracetamol (PCM), chlorzoxazone (CXZ), and their related impurities in bulk raw materials and solid dosage forms. The mobile phase consisted of water-methanol-glacial acetic acid (60 + 40 + 2, v/v/v). A column containing octadecylsilane chemically bonded to porous silica particles (Spherisorb ODS 1, 25 cm x 4.6 mm, 5 microm) was used as stationary phase. Detection was performed using a variable wavelength ultraviolet-visible detector set at 272 nm for all compounds. Solutions were injected into the chromatograph under isocratic condition at a constant flow rate of 1.2 mL/min. The method was validated according to International Conference on Harmonization requirements and demonstrates good accuracy and precision and a wide linearity range. The method separates PCM, CXZ, and 3 major impurities [4-aminophenol (4AP), 4'-chloracetanilide (4CA), and p-chlorophenol (PCP)] with fair resolution in less than 15 min. The developed method is rapid and sensitive (limit of detection for 4AP, 4CA, and PCP established at 31.25, 39.06, and 65.16 ng/mL, respectively) and, therefore, suitable for quality control and stability studies of these compounds in dosage forms. 相似文献
85.
We investigate the influence of the first-order correction of entropy caused by thermal quantum fluctuations on the thermodynamics of a logarithmic corrected charged black hole in massive gravity. For this black hole, we explore the thermodynamic quantities, such as entropy, Helmholtz free energy, internal energy, enthalpy, Gibbs free energy and specific heat. We discuss the influence of the topology of the event horizon, dimensions and nonlinearity parameter on the local and global stability of the black hole. As a result, it is found that the holographic dual parameter vanishes. This means that the thermal corrections have no significant role to disturb the holographic duality of the logarithmic charged black hole in massive gravity, although the thermal corrections have a substantial impact on the thermodynamic quantities in the high-energy limit and the stability conditions of black holes. 相似文献
86.
Chiral recognition of aryl alkyl selenides and alkyl iodides can be achieved by 1H NMR spectroscopy in the presence of dirhodium tetra-(R)-or tetra-(S)-α-methoxy-α-(trifluoromethyl)-phenylacetate [Rh2(MTPA)4, 1 ]. Generally, these classes of compounds are weak donors and fail when using the classical chiral lanthanoid shift reagent. Alkyl bromides do not show similar effects. © 1998 John Wiley & Sons, Inc. Heteroatom Chem 9:471–474, 1998 相似文献
87.
Prabal Datta Barua Wai Yee Chan Sengul Dogan Mehmet Baygin Turker Tuncer Edward J. Ciaccio Nazrul Islam Kang Hao Cheong Zakia Sultana Shahid U. Rajendra Acharya 《Entropy (Basel, Switzerland)》2021,23(12)
Optical coherence tomography (OCT) images coupled with many learning techniques have been developed to diagnose retinal disorders. This work aims to develop a novel framework for extracting deep features from 18 pre-trained convolutional neural networks (CNN) and to attain high performance using OCT images. In this work, we have developed a new framework for automated detection of retinal disorders using transfer learning. This model consists of three phases: deep fused and multilevel feature extraction, using 18 pre-trained networks and tent maximal pooling, feature selection with ReliefF, and classification using the optimized classifier. The novelty of this proposed framework is the feature generation using widely used CNNs and to select the most suitable features for classification. The extracted features using our proposed intelligent feature extractor are fed to iterative ReliefF (IRF) to automatically select the best feature vector. The quadratic support vector machine (QSVM) is utilized as a classifier in this work. We have developed our model using two public OCT image datasets, and they are named database 1 (DB1) and database 2 (DB2). The proposed framework can attain 97.40% and 100% classification accuracies using the two OCT datasets, DB1 and DB2, respectively. These results illustrate the success of our model. 相似文献
88.
Aftab Shaukat Irfan Shaukat Shahid Ali Rajput Rizwan Shukat Sana Hanif Imran Shaukat Xinxin Zhang Chao Chen Xuyang Sun Tingzhu Ye Kaifeng Niu Zhiqiu Yao Shadab Shaukat Muhammad Safdar Mohamed Abdelrahman Umair Riaz Junwei Zhao Xiaoying Gu Liguo Yang 《Molecules (Basel, Switzerland)》2021,26(23)
Endometritis is the inflammatory response of the endometrial lining of the uterus and is associated with low conception rates, early embryonic mortality, and prolonged inter-calving intervals, and thus poses huge economic losses to the dairy industry worldwide. Ginsenoside Rb1 (GnRb1) is a natural compound obtained from the roots of Panax ginseng, having several pharmacological and biological properties. However, the anti-inflammatory properties of GnRb1 in lipopolysaccharide (LPS)-challenged endometritis through the TLR4-mediated NF-κB signaling pathway has not yet been researched. This study was planned to evaluate the mechanisms of how GnRb1 rescues LPS-induced endometritis. In the present research, histopathological findings revealed that GnRb1 ameliorated LPS-triggered uterine injury. The ELISA and RT-qPCR assay findings indicated that GnRb1 suppressed the expression level of pro-inflammatory molecules (TNF-α, IL-1β and IL-6) and boosted the level of anti-inflammatory (IL-10) cytokine. Furthermore, the molecular study suggested that GnRb1 attenuated TLR4-mediated NF-κB signaling. The results demonstrated the therapeutic efficacy of GnRb1 in the mouse model of LPS-triggered endometritis via the inhibition of the TLR4-associated NF-κB pathway. Taken together, this study provides a baseline for the protective effect of GnRb1 to treat endometritis in both humans and animals. 相似文献
89.
Nauman Raza Sultan Sial Shahid S. Siddiqi Turab Lookman 《Journal of computational physics》2009,228(7):2572-2577
In this the window of the Sobolev gradient technique to the problem of minimizing a Schrödinger functional associated with a nonlinear Schrödinger equation. We show that gradients act in a suitably chosen Sobolev space (Sobolev gradients) can be used in finite-difference and finite-element settings in a computationally efficient way to find minimum energy states of Schrödinger functionals. 相似文献
90.
A simple and efficient method for the iodination of aromatic compounds has been achieved in the presence of iodine and 1,4-bis(triphenylphosphonium)-2-butene peroxodisulfate. 相似文献