检索结果-内蒙古大学图书馆

CONVERGENCE RATE OF GRADIENT DESCENT METHOD FOR MULTI-OBJECTIVE OPTIMIZATION

Journal of computational Mathematics 2019年第5期37卷 689-703页

作者： Liaoyuan Zeng Yuhong Dai Yakui Huang Institute of Computational Mathematics and Scientific/Engineering Computing State Key Labomtory of Scientific and Engineering ComputingAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Science Hebei University of TechnologyTianjin 300401 China

The convergence rate of the gradient descent method is considered for unconstrained multi-objective optimization problems (MOP). Under standard assumptions, we prove that the gradient descent method with constant stepsizes converges sublinearly when the objective functions are convex and the convergence rate can be strengthened to be linear if the objective functions are strongly convex. The results are also extended to the gradient descent method with the Armijo line search. Hence, we see that the gradient descent method for MOP enjoys the same convergence properties as those for scalar optimization.

关键词： Multi-objective optimization Gradient descent Convergence rate.

来源：评论

学校读者我要写书评

暂无评论

Non-rigid Medical Image Registration using Physics-informed Neural Networks

arXiv

引用

arXiv 2023年

作者： Min, Zhe Baum, Zachary M.C. Saeed, Shaheer U. Emberton, Mark Barratt, Dean C. Taylor, Zeike A. Hu, Yipeng Centre for Medical Image Computing and Wellcome EPSRC Centre for Interventional & Surgical Sciences University College London London United Kingdom Division of Surgery & Interventional Science University College London London United Kingdom CISTIB Centre for Computational Imaging and Simulation Technologies in Biomedicine Institute of Medical and Biological Engineering University of Leeds Leeds United Kingdom

Biomechanical modelling of soft tissue provides a non-data-driven method for constraining medical image registration, such that the estimated spatial transformation is considered biophysically plausible. This has not only been adopted in real-world clinical applications, such as the MR-to-ultrasound registration for prostate intervention of interest in this work, but also provides an explainable means of understanding the organ motion and spatial correspondence establishment. This work instantiates the recently-proposed physics-informed neural networks (PINNs) to a 3D linear elastic model for modelling prostate motion commonly encountered during transrectal ultrasound guided procedures. To overcome a widely-recognised challenge in generalising PINNs to different subjects, we propose to use PointNet as the nodal-permutation-invariant feature extractor, together with a registration algorithm that aligns point sets and simultaneously takes into account the PINN-imposed biomechanics. Using 77 pairs of MR and ultrasound images from real clinical prostate cancer biopsy, we first demonstrate the efficacy of the proposed registration algorithms in an "unsupervised" subject-specific manner for reducing the target registration error (TRE) compared to that without PINNs especially for patients with large deformations. The improvements stem from the intended biomechanical characteristics being regularised, e.g., the resulting deformation magnitude in rigid transition zones was effectively modulated to be smaller than that in softer peripheral zones. This is further validated to achieve low registration error values of 1.90 ± 0.52 mm and 1.94 ± 0.59 mm for all and surface nodes, respectively, based on ground-truth computed using finite element methods. We then extend and validate the PINN-constrained registration network that can generalise to new subjects. The trained network reduced the rigid-to-soft-region ratio of rigid-excluded deformation magnitude from 1.35 ± 0.15, withou

关键词： Urology

来源：评论

学校读者我要写书评

暂无评论

Energy-Efficient Beamforming Design for Integrated Sensing and Communications Systems

arXiv

引用

arXiv 2023年

作者： Zou, Jiaqi Sun, Songlin Masouros, Christos Cui, Yuanhao Liu, Ya-Feng Ng, Derrick Wing Kwan Beijing100876 China The Department of Electrical and Electronic Engineering University College London LondonWC1E 7JE United Kingdom Beijing China The Department of Electrical and Electronic Engineering University College London WC1E 7JE United Kingdom The State Key Laboratory of Scientific and Engineering Computing Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing100190 China The School of Electrical Engineering and Telecommunications University of New South Wales SydneyNSW2052 Australia

In this paper, we investigate the design of energy-efficient beamforming for an ISAC system, where the transmitted waveform is optimized for joint multi-user communication and target estimation simultaneously. We aim to maximize the system energy efficiency (EE), taking into account the constraints of a maximum transmit power budget, a minimum required signal-to-interference-plus-noise ratio (SINR) for communication, and a maximum tolerable Cramér-Rao bound (CRB) for target estimation. We first consider communication-centric EE maximization. To handle the non-convex fractional objective function, we propose an iterative quadratic-transform-Dinkelbach method, where Schur complement and semi-definite relaxation (SDR) techniques are leveraged to solve the subproblem in each iteration. For the scenarios where sensing is critical, we propose a novel performance metric for characterizing the sensing-centric EE and optimize the metric adopted in the scenario of sensing a point-like target and an extended target. To handle the nonconvexity, we employ the successive convex approximation (SCA) technique to develop an efficient algorithm for approximating the nonconvex problem as a sequence of convex ones. Furthermore, we adopt a Pareto optimization mechanism to articulate the tradeoff between the communication-centric EE and sensing-centric EE. We formulate the search of the Pareto boundary as a constrained optimization problem and propose a computationally efficient algorithm to handle it. Numerical results validate the effectiveness of our proposed algorithms compared with the baseline schemes and the obtained approximate Pareto boundary shows that there is a non-trivial tradeoff between communication-centric EE and sensing-centric EE, where the number of communication users and EE requirements have serious effects on the achievable tradeoff. © 2023, CC BY-NC-ND.

关键词： Energy efficiency

来源：评论

学校读者我要写书评

暂无评论

Novel Structure-Preserving Schemes for Stochastic Klein-Gordon-Schr\"Odinger Equations with Additive Noise

SSRN

引用

SSRN 2023年

作者： Hong, Jialin Hou, Baohui Sun, Liying Zhang, Xiaojing Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing100190 China School of Mathematical Sciences University of Chinese Academy of Sciences Beijing100049 China Department of Mathematics Shanghai University Shanghai200444 China School of Mathematical Sciences Capital Normal University Beijing100048 China

Stochastic Klein–Gordon–Schr¨odinger (KGS) equations are important mathematical models and describe the interaction between scalar nucleons and neutral scalar mesons in the stochastic environment. In this paper, we propose novel structure-preserving schemes to numerically solve stochastic KGS equations with additive noise, which preserve averaged charge evolution law, averaged energy evolution law, symplecticity, and multi-symplecticity. By applying central difference, sine pseudo-spectral method, or finite element method in space and modifying finite difference in time, we present some charge and energy preserved fullydiscrete scheme for the original system. In addition, combining the symplectic Runge-Kutta method in time and finite difference in space, we propose a class of multi-symplectic discretizations preserving the geometric structure of the stochastic KGS equation. Finally, numerical experiments confirm theoretical findings. © 2023, The Authors. All rights reserved.

关键词： Additive noise

来源：评论

学校读者我要写书评

暂无评论

Improved Red Deer Algorithm for Scientific Workflow Scheduling in Cloud Environment

Improved Red Deer Algorithm for Scientific Workflow Scheduli...

引用

International Conference on Inventive Research in computing Applications (ICIRCA)

作者： Chandra Mouli Venkata Srinivas Hajiyeva Rena AR. Arunarani ST Naitik Mohammed Saleh Al Ansari Ammar Younas Bonam Venkata Chalamayya Engineering College Odalarevu Andhra Pradesh India Department of Information Technologies Azerbaijan Western Caspian University Azerbaijan Department of Computational Intelligence School of Computing College of Engineering and Technology SRM Institute of Science and Technology Chennai Tamilnadu India CSE department Dayananda Sagar University Bangalore Karnataka India Department of Chemical Engineering College of Engineering University of Bahrain Bahrain Department of Business Law Tashkent State University of Law Uzbekistan

One of the most difficult problems in the technological sector is the versatility of cloud computing, which can offer a flexible and responsive infrastructure in the realm of information technology. A significant problem in cloud computing that is addressed in recent research is workflow scheduling. With the quick advancement of cloud computing, scheduling the intricate scientific process on the cloud has grown to be an incredibly difficult task. It has been identified that one of the key challenges to optimizing the performance of cloud computing is scheduling workflow tasks so that it is processed by the most effective cloud network resources. Meta-heuristic optimization algorithms are frequently utilized to find a solution to effective task scheduling because of the intricacy of the problem and the extent of the search space. This research suggests a unique Improved Red Deer Algorithm (IRDA) to shorten execution time subject to a set budget. The performance of the proposed algorithm is evaluated against conventional optimization algorithms by applying it to scientific workflows including Montage and Epigenomics. The experimental results reveal that the proposed algorithm works better than other compared methods in reducing workflow task execution time and cost.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Learning Collective Cell Migratory Dynamics from a Static Snapshot with Graph Neural Networks

引用

PRX Life 2024年第4期2卷 043010页

作者： Haiqian Yang Florian Meyer Shaoxun Huang Liu Yang Cristiana Lungu Monilola A. Olayioye Markus J. Buehler Ming Guo Department of Mechanical Engineering Institute of Cell Biology and Immunology Department of Computer Sciences Laboratory for Atomistic and Molecular Mechanics (LAMM) Center for Computational Science and Engineering Schwarzman College of Computing

Multicellular self-assembly into functional structures is a dynamic process that is critical in the development of biological structures and diseases, including embryo development, organ formation, tumor invasion, and other processes. Being able to infer collective cell migratory dynamics from their static configuration is valuable for both understanding and predicting these complex behaviors. However, the identification of structural features that can indicate multicellular motion has been difficult, and existing metrics largely rely on physical instincts. Here we show that, through the use of a graph neural network, the motion of multicellular collectives can be inferred from a static snapshot of cell positions, in both experimental and synthetic datasets.

关键词： Cell assembly Cell locomotion Cellular organization, physiology & dynamics Deep learning

来源：评论

学校读者我要写书评

暂无评论

Rubric-based holistic review represents a change from traditional graduate admissions approaches in physics

引用

Physical Review Physics Education Research 2023年第1期19卷 010134-010134页

作者： Nicholas T. Young N. Verboncoeur Dao Chi Lam Marcos D. Caballero Department of Physics and Astronomy Michigan State University East Lansing Michigan 48824 USA Department of Computational Mathematics Science and Engineering Michigan State University East Lansing Michigan 48824 USA Department of Statistics Michigan State University East Lansing Michigan 48824 USA Center for Computing in Science Education and Department of Physics University of Oslo N-0316 Oslo Norway CREATE for STEM Institute Michigan State University East Lansing Michigan 48824 USA

Rubric-based admissions are claimed to help make the graduate admissions process more equitable, possibly helping to address the historical and ongoing inequities in the U.S. physics graduate school admissions process that have often excluded applicants from minoritized races, ethnicities, genders, and backgrounds. Yet, no studies have examined whether rubric-based admissions methods represent a fundamental change in the admissions process or simply represent a new tool that achieves the same outcome. To address that, we developed supervised machine learning models of graduate admissions data collected from our department over a seven-year period. During the first four years, our department used a traditional admission process and switched to a rubric-based process for the following three years, allowing us to compare which parts of the applications were driving admissions decisions. We find that faculty focused on applicants’ physics GRE scores and grade-point averages when making admissions decisions before the implementation of the rubric. While we were able to develop a sufficiently good model whose results we could trust for the data before the implementation of the rubric, we were unable to do so for the data collected after the implementation of the rubric, despite multiple modifications to the algorithms and data such as implementing Tomek Links. Our inability to model the second dataset despite being able to model the first combined with model comparison analyses suggests that rubric-based admission does change the underlying process. These results suggest that rubric-based holistic review is a method that could make the graduate admission process in physics more equitable.

关键词： Diversity & inclusion Educational policy Graduate students

来源：评论

学校读者我要写书评

暂无评论

A Robust Remote Client Password Authentication Technique for Smart Cities E-Governance Applications

A Robust Remote Client Password Authentication Technique for...

引用

2023 IEEE International Conference on Communications, computing, Cybersecurity and Informatics, CCCI 2023

作者： Obaidat, Mohammad S. Meshram, Chandrashekhar Kartikey, Deepak Hsiao, Kuei-Fang Imoize, Agbotiname Lucky Barve, Sharad Kumar Abdullah Ii School of Information Technology The University of Jordan Amman11942 Jordan School of Computer and Communication Engineering University of Science and Technology Beijing Beijing100083 China School of Computing Srm University Department of Computational Intelligence TN Kattankulathur603203 India School of Engineering The Amity University UP Noida201301 India Jayawanti Haksar Government Post Graduation College College of Barkatullah University Department of Post Graduation Studies and Research in Mathematics M.P. Betul460001 India S.S.P. Govt. College Waraseoni Department of Mathematics M.P. Balaghat India University of Texas-Permian Basin Computer Science Department OdessaTX79762 United States University of Lagos Faculty of Engineering Department of Electrical and Electronics Engineering Lagos100213 Nigeria Institute of Digital Communication Ruhr University Department of Electrical Engineering and Information Technology Bochum44801 Germany Pandit S. N. Shukla University Shahdol Department of Mathematics Madhya Pradesh Shahdol484001 India

ISBN: (纸本)9798350302561

Smart cities are fast proliferating the global space in recent times. In order to achieve the envisioned next-generation cities, the smart city paradigm aspires to develop a completely integrated network-based infrastructure. With the development of innovative smart cities, ICT-based e-governance has made it possible for services to be delivered intelligently and interactively via online platforms. However, the communication between government agencies and other stakeholders in the smart city ecosystem is through open channels, which poses serious security concerns. In order to address this problem, this work proposes a robust remote client password authentication technique for e-governance applications in smart cities. The proposed authentication technique is lightweight, resistant to several attacks, and achieves low computational overhead. © 2023 IEEE.

关键词： Smart cards

来源：评论

学校读者我要写书评

暂无评论

Automation Intervention for Monitoring Agriculture Farming Scale: A Review

Automation Intervention for Monitoring Agriculture Farming S...

引用

International Conference on computing and Networking Technology (ICCNT)

作者： Kapil Joshi Santosh Kumar Shruti Bhatla Vishal Kaushik Harishchander Anandaram Anil Kumar Department of CSE Uttaranchal Institute of Technology Uttaranchal University Dehradun India Department of Mathematics Sharda School of Basic Sciences and Research Sharda University Greater Noida UP India Department of Computer Science and Engineering Graphic Era Hill University Dehradun Uttarakhand India School of Computer Science UPES Dehradun India Centre for Computational Engineering and Networking Amrita Vishwa Vidyapeetham Coimbatore Tamil Nadu India School of Computing DIT University Dehradun India

Agricultural data is only valuable when it has been managed successfully. As data has evolved into the fundamental ingredient in contemporary agriculture to assist farmers with vital decision, latest developments in managing data are causing Smart Agriculture to rise dramatically. With factual information obtained by sensors, significant advantages emerge with the goal of enhancing production and ecology. This type of data-driven farm management is built on information that can boost efficiency by preventing resource waste and contamination of the ecosystem. Data-driven farming, with the assistance of automated solutions using artificial intelligence techniques, lays the groundwork for potential sustainable *** article analyses the current state of sophisticated agricultural systems by rehashing each critical step, from data processing in field crops to variable interest rate implementations, so that farmers can make optimised decision making to save funds while safeguarding the natural environment and converting how meal would be generated to meet the upcoming population explosion.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Integrating Deep Learning with Fundus and Optical Coherence Tomography for Cardiovascular Disease Prediction

arXiv

引用

arXiv 2024年

作者： Maldonado-Garcia, Cynthia Zakeri, Arezoo Frangi, Alejandro F. Ravikumar, Nishant Centre for Computational Imaging and Simulation Technologies in Biomedicine School of Computing University of Leeds Leeds United Kingdom Division of Informatics Imaging and Data Sciences School of Health Sciences Faculty of Biology Medicine and Health University of Manchester Manchester United Kingdom School of Computer Science Faculty of Science and Engineering University of Manchester Kilburn Building Manchester United Kingdom Christabel Pankhurst Institute University of Manchester Manchester United Kingdom NIHR Manchester Biomedical Research Centre Manchester Academic Health Science Centre Manchester United Kingdom

Early identification of patients at risk of cardiovascular diseases (CVD) is crucial for effective preventive care, reducing healthcare burden, and improving patients’ quality of life. This study demonstrates the potential of retinal optical coherence tomography (OCT) imaging in conjunction with fundus photographs for identifying future adverse cardiac events. We utilized data from 977 patients who experienced CVD within a 5-year interval post-image acquisition, alongside 1,877 control participants without CVD, totaling 2,854 subjects. We propose a novel binary classification network based on a Multi-channel Variational Autoencoder (MCVAE), which learns a latent embedding of patients’ fundus and OCT images to classify individuals into two groups: those likely to develop CVD in the future and those who are not. Our model, trained on both imaging modalities, achieved promising results (AUROC 0.78 ± 0.02, accuracy 0.68 ± 0.002, precision 0.74 ± 0.02, sensitivity 0.73 ± 0.02, and specificity 0.68 ± 0.01), demonstrating its efficacy in identifying patients at risk of future CVD events based on their retinal images. This study highlights the potential of retinal OCT imaging and fundus photographs as cost-effective, non-invasive alternatives for predicting cardiovascular disease risk. The widespread availability of these imaging techniques in optometry practices and hospitals further enhances their potential for large-scale CVD risk screening. Our findings contribute to the development of standardized, accessible methods for early CVD risk identification, potentially improving preventive care strategies and patient outcomes. © 2024, CC BY-NC-ND.

关键词：

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：