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PDE Constrained Optimization and Design of Frozen Mode Crystals

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Communications in Computational Physics 2008年第4期3卷 878-898页

作者： s.chun J.s.Hesthaven Division of Applied Mathematics Brown UniversityProvidenceRI 02912USA.

We explore the use of PDE constrained nonlinear optimization techniques to optimize and design electromagnetic crystals which exhibit frozen mode *** is characterized by Van Hove singularities in the dispersion relation,e.g.,stationary reflection points and degenerate band edge ***,the optimization process modifies the dispersion relation by adjusting the geometries and material *** resulting algorithm is found to be capable of recovering all known crystal configurations as well as many new configurations,some of which display dramatically improved properties over previously used *** investigate both gyrotropic photonic crystals and degenerate band edge crystals as well as the more complex case of the oblique *** this latter case,we extend the investigation to the three-dimensional case to identify the first three-dimensional crystal exhibiting frozen mode behavior.

关键词： PDE constrained optimization method of matched asymptotics frozen mode photonic crystal.

Treatment and disease management patterns for bacillus Calmette-Guérin unresponsive nonmuscle invasive bladder cancer in North America,Europe and Asia:A real-world data analysis

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Current Urology 2022年第3期16卷 147-153页

作者： Edward I.Broughton Danielle s.chun Kyna M.Gooden Katie L.Mycock Ivana Rajkovic Gavin Taylor-stokes WW Health Economics and Outcomes Research Bristol Myers SquibbPrincetonNJUSA The University of North Carolina Chapel HillNCUSA Observational Research Department Adelphi Real WorldBollingtonUK

Background:This study examined real-world treatment and management of bacillus Calmette-Guérin(BCG)-unresponsive patients across 3 continents,including patients unable or unwilling to undergo *** and methods:Physicians actively involved in managing patients with nonmuscle invasive bladder cancer completed online case report forms for their 5 consecutive patients from the broad BCG-unresponsive population and a further 5 consecutive BCG-unresponsive patients who did not undergo cystectomy(in Japan,physicians provided a total of 5 patients across both cohorts).Results:Most patients had received 1(37%)or 2(24%)maintenance courses of *** or more maintenance BCG courses were received by patients in Japan(59%)and China(31%),while in Germany 76%of patients received only 1 *** patients became BCG-unresponsive during their first(44%)or second(22%)treatment course;in Germany,77%became BCG-unresponsive during their first treatment *** countries did not provide another course of BCG after a patient first became unresponsive,whereas unresponsive patients in Japan and China were most likely to be retreated with BCG."Untreated-on watch and wait"was the main treatment/management approach received post-BCG treatment for 42%or more of patients in most countries except China(39%)and the United states(36%)."Following treatment guidelines"was consistently the top reason for post-BCG treatment selection across all treatment ***:This study confirmed the global unmet need for patients with nonmuscle invasive bladder cancer,and found that many patients experienced periods of no treatment after not responding to BCG therapy.

关键词： Bacillus Calmette-Guérin Bladder cancer Cystectomy Treatment failure Urinary tract

Coupling Analysis of Multiple Machine Learning Models for Human Activity Recognition

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Computers, Materials & Continua 2024年第6期79卷 3783-3803页

作者： Yi-chun Lai shu-Yin Chiang Yao-Chiang Kan Hsueh-chun Lin Department of Public Health China Medical UniversityTaichung406040Taiwan Department of Information and Telecommunications Engineering Ming Chuan UniversityGui-ShanTaoyuan333Taiwan Department of Electrical Engineering Yuan Ze UniversityChung-Li32003Taiwan Department and Institute of Health service Administrations China Medical UniversityTaichung406040Taiwan

Artificial intelligence(AI)technology has become integral in the realm of medicine and healthcare,particularly in human activity recognition(HAR)applications such as fitness and rehabilitation *** study introduces a robust coupling analysis framework that integrates four AI-enabled models,combining both machine learning(ML)and deep learning(DL)approaches to evaluate their effectiveness in *** analytical dataset comprises 561 features sourced from the UCI-HAR database,forming the foundation for training the ***,the MHEALTH database is employed to replicate the modeling process for comparative purposes,while inclusion of the WIsDM database,renowned for its challenging features,supports the framework’s resilience and *** ML-based models employ the methodologies including adaptive neuro-fuzzy inference system(ANFIs),support vector machine(sVM),and random forest(RF),for data *** contrast,a DL-based model utilizes one-dimensional convolution neural network(1dCNN)to automate feature ***,the recursive feature elimination(RFE)algorithm,which drives an ML-based estimator to eliminate low-participation features,helps identify the optimal features for enhancing model *** best accuracies of the ANFIs,sVM,RF,and 1dCNN models with meticulous featuring process achieve around 90%,96%,91%,and 93%,*** analysis using the MHEALTH dataset showcases the 1dCNN model’s remarkable perfect accuracy(100%),while the RF,sVM,and ANFIs models equipped with selected features achieve accuracies of 99.8%,99.7%,and 96.5%,***,when applied to the WIsDM dataset,the DL-based and ML-based models attain accuracies of 91.4%and 87.3%,respectively,aligning with prior research *** conclusion,the proposed framework yields HAR models with commendable performance metrics,exhibiting its suitability for integration into the healthcare services system through AI-driven applications.

关键词： Human activity recognition artificial intelligence support vector machine random forest adaptive neuro-fuzzy inference system convolution neural network recursive feature elimination

Eigenstate properties of the disordered Bose-Hubbard chain

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Frontiers of physics 2024年第4期19卷 57-72页

作者： Jie Chen chun Chen Xiaoqun Wang Key Laboratory of Artificial structures and Quantum Control(Ministry of Education) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China school of Physics Zhejiang UniversityHangzhou 310058China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

Many-body localization(MBL)of a disordered interacting boson system in one dimension is studied numerically at the filling faction *** von Neumann entanglement entropy svn is commonly used to detect the MBL phase transition but remains challenging to be directly *** on the U(1)symmetry from the particle number conservation,svn can be decomposed into the particle number entropy s_(n) and the configuration entropy *** light of the tendency that the eigenstate's s_(c) nears zero in the localized phase,we introduce a quantity describing the deviation of s from the ideal thermalization distribution;finite-size scaling analysis illustrates that it shares the same phase transition point with sv but displays the better critical *** observation hints that the phase transition to MBL might largely be determined by s and its fluctuations Notably,the recent experiments[***,et al.,science 364,256(2019);***,et al.,***.19,481(2023)]demonstrated that this deviation can potentially be measured through the sn ***,our investigations reveal that the thermalized states primarily occupy the low-energy section of the spectrum,as indicated by measures of localization length,gap ratio,and energy density *** low-energy spectrum of the Bose model closely resembles the entire spectrum of the Fermi(or spin XXZ)model,accommodating a transition from the thermalized to the localized ***,owing to the bosonic statistics,the high-energy spectrum of the model allows the formation of distinct clusters of bosons in the random potential *** analyze the resulting eigenstate properties and briefly summarize the associated *** distinguish between the phase regions at the low and high energies,a probing quantity based on the structure of s_(VN) is also *** work highlights the importance of symmetry combined with entanglement in the study of *** this regard,for the disordered Heisenberg XXZ

关键词： entanglement entropy decomposition U(1)symmetry thermalization-to-localization transition

In-situ powder mixing for laser-based directed energy deposition of functionally graded materials

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Advances in Manufacturing 2024年第1期12卷 150-166页

作者： Ji-Peng Chen shou-chun Xie He Huang school of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing210037People’s Republic of China Nanjing Huirui Photoelectric Technology Co. LtdNanjing211121People’s Republic of China

The mixing of powders is a highly relevant field under additive manufacturing,however,it has attracted limited interest to *** in-situ mixing of various powders remains a significant *** paper proposes a new method utilizing a static mixer for the in-situ mixing of multiple powders through the laser-based directed energy deposition(DED)of functionally graded ***,a powder-mixing experimental platform was established;WC and 316L powders were selected for the mixing ***,scanning electron microscopy,energy dispersive spectroscopy,and image processing were used to visually evaluate the homogeneity and proportion of the in-situ mixed ***,powder-mixing simulations were conducted to determine the powder-mixing *** the simulations,a powder carrier gas flow field and particle mixing were ***,a WC/316L metal matrix composite sample was produced using laser-based DED to verify the application potential of the static *** was found that the static mixer could adjust the powder ratio online,and a response time of 1–2 s should be considered when adjusting the ratio of the mixed powder.A feasible approach for in-situ powder mixing for laser-based DED was demonstrated and investigated,creating the basis for functionally graded materials.

关键词： Laser Deposition static mixer Powder mixing Functionally graded materials

saliency-guided meta-hallucinator for few-shot learning

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science China(Information sciences) 2024年第10期67卷 189-210页

作者： Hongguang ZHANG chun LIU Jiandong WANG Linru MA Piotr KONIUsZ Philip H.s.TORR Lin YANG systems Engineering Institute Academy of Military Sciences Data61 Commonwealth Scientific and Industrial Research Organisation Australian National University Oxford University

Learning novel object concepts from limited samples remains a considerable challenge in deep learning. The main directions for improving the few-shot learning models include(i) designing a stronger backbone,(ii) designing a powerful(dynamic) meta-classifier, and(iii) using a larger pre-training set obtained by generating or hallucinating additional samples from the small scale dataset. In this paper, we focus on item(iii) and present a novel meta-hallucination strategy. Presently, most image generators are based on a generative network(i.e., GAN) that generates new samples from the captured distribution of images. However, such networks require numerous annotated samples for training. In contrast, we propose a novel saliency-based end-to-end meta-hallucinator, where a saliency detector produces foregrounds and backgrounds of support images. such images are fed into a two-stream network to hallucinate feature samples directly in the feature space by mixing foreground and background feature samples. Then, we propose several novel mixing strategies that improve the quality and diversity of hallucinated feature ***, as not all saliency maps are meaningful or high quality, we further introduce a meta-hallucination controller that decides which foreground feature samples should participate in mixing with backgrounds. To our knowledge, we are the first to leverage saliency detection for few-shot learning. Our proposed network achieves state-of-the-art results on publicly available few-shot image classification and anomaly detection benchmarks, and outperforms competing sample mixing strategies such as the so-called Manifold Mixup.

关键词： few-shot learning saliency detection object recognition anomaly detection computer vision

Differential Evolution Hemivariational Inequalities with Anti-periodic Conditions

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Acta Mathematica sinica,English series 2024年第4期40卷 1143-1160页

作者： Jing ZHAO chun Mei GAN Zhen Hai LIU school of Mathematics and Quantitative Economics Guangxi University of Finance and EconomicsNanning 530003P.R.China Guangxi Colleges and Universities Key Laboratory of Optimization Control and Engineering Calculation Guangxi Minzu UniversityNanning 530006P.R.China

The goal of this paper is to deal with a new dynamic system called a differential evolution hemivariational inequality(DEHVI)which couples an abstract parabolic evolution hemivariational inequality and a nonlinear differential equation in a Banach ***,by apply ing surjectivity result for pseudomonotone multivalued mappins and the properties of Clarke's subgradient,we show the nonempty of the solution set for the parabolic hemivariational ***,some topological properties of the solution set are established such as boundedness,closedness and ***,we explore the upper semicontinuity of the solution ***,we prove the solution set of the system(DEHVI)is nonempty and the set of all trajectories of(DEHVI)is weakly compact in C(I,X).

关键词： Differential parabolic hemivariational inequality Clarke subdifferential hyperbolicparabolic system parabolic-parabolic system existence result

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stochastic resonance of spinor condensates in optical cavity

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science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 80-87页

作者： Zheng-chun Li Bixuan Fan Lu Zhou Weiping Zhang school of Physics and Astronomy and Tsung-Dao Lee InstituteShanghai Jiao Tong UniversityShanghai 200240China state Key Laboratory of Precision spectroscopy School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China College of Physics and Communication Electronics Jiangxi Normal UniversityNanchang 330022China shanghai Branch Hefei National LaboratoryShanghai 201315China shanghai Research Center for Quantum sciences Shanghai 201315China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

stochastic resonance is a phenomenon in which adding random noise to a system enhances the detection or transmission of a weak signal. It occurs when the noise interacts with the system's nonlinearity, thus improving signal-to-noise ratio and increasing sensitivity. Although parametric resonances in an atomic spinor Bose-Einstein condensate have been investigated, the question of whether one can observe stochastic resonance in such a system persists. In this study we propose a scheme for generating stochastic resonance in a cavity-spinor Bose-Einstein condensate coupling system. We demonstrate stochastic resonance through numerical calculations using the mean-field theory and truncated Wigner approximation methods. Furthermore, the characteristics of the system's response to noise and periodic signals are studied in detail. This study unravels a new scheme for observing stochastic resonance via linking atomic many-body physics with cavity quantum electrodynamics.

关键词： spinor condensate stochastic resonance optical cavity

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Optimal investment based on relative performance and weighted utility

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 328-342页

作者： WANG Lei DONG Ying-hui HUA chun-rong Department of Mathematics Suzhou University of Science and TechnologySuzhou 215009China Changshu Institute of Technology Changshu 215500China

This paper studies the optimal portfolio allocation of a fund manager when he bases decisions on both the absolute level of terminal relative performance and the change value of terminal relative performance comparison to a predefined reference point. We find the optimal investment strategy by maximizing a weighted average utility of a concave utility and an sshaped utility via a concavification technique and the martingale method. Numerical results are carried out to show the impact of the extent to which the manager pays attention to the change of relative performance related to the reference point on the optimal terminal relative performance.

关键词： relative performance weighted utility s-shaped utility concavification

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