检索结果-内蒙古大学图书馆

Deep bed filtration model for cake filtration and erosion

applied mathematics and Mechanics(English Edition) 2024年第2期45卷 355-372页

作者： L.I.KUZMINA Y.V.OSIPOV A.R.PESTEREV Department of Applied Mathematics HSE UniversityMoscow 101000Russia Department of Computer Science and Applied Mathematics Moscow State University of Civil EngineeringMoscow 129337Russia

Many phenomena in nature and technology are associated with the filtration of suspensions and colloids in porous media. Two main types of particle deposition,namely, cake filtration at the inlet and deep bed filtration throughout the entire porous medium, are studied by different models. A unified approach for the transport and deposition of particles based on the deep bed filtration model is proposed. A variable suspension flow rate, proportional to the number of free pores at the inlet of the porous medium, is considered. To model cake filtration, this flow rate is introduced into the mass balance equation of deep bed filtration. For the cake filtration without deposit erosion,the suspension flow rate decreases to zero, and the suspension does not penetrate deep into the porous medium. In the case of the cake filtration with erosion, the suspension flow rate is nonzero, and the deposit is distributed throughout the entire porous medium. An exact solution is obtained for a constant filtration function. The method of characteristics is used to construct the asymptotics of the concentration front of suspended and retained particles for a filtration function in a general form. Explicit formulae are obtained for a linear filtration function. The properties of these solutions are studied in detail.

关键词： deep bed filtration cake filtration porous medium particle deposition and erosion analytical solution concentration front

来源：评论

学校读者我要写书评

暂无评论

Context-aware reinforcement learning for cooling operation of data centers with an Aquifer Thermal Energy Storage

引用

Energy and AI 2024年第3期17卷 233-246页

作者： Lukas Leindals Peter Grønning Dominik Franjo Dominković Rune Grønborg Junker Department of Applied Mathematics and Computer Science Technical University of DenmarkDenmark

Data centers are often equipped with multiple cooling units. Here, an aquifer thermal energy storage (ATES) system has shown to be efficient. However, the usage of hot and cold-water wells in the ATES must be balanced for legal and environmental reasons. Reinforcement Learning has been proven to be a useful tool for optimizing the cooling operation at data centers. Nonetheless, since cooling demand changes continuously, balancing the ATES usage on a yearly basis imposes an additional challenge in the form of a delayed reward. To overcome this, we formulate a return decomposition, Cool-RUDDER, which relies on simple domain knowledge and needs no training. We trained a proximal policy optimization agent to keep server temperatures steady while minimizing operational costs. Comparing the Cool-RUDDER reward signal to other ATES-associated rewards, all models kept the server temperatures steady at around 30 °C. An optimal ATES balance was defined to be 0% and a yearly imbalance of −4.9% with a confidence interval of [−6.2, −3.8]% was achieved for the Cool 2.0 reward. This outperformed a baseline ATES-associated reward of 0 at −16.3% with a confidence interval of [−17.1, −15.4]% and all other ATES-associated rewards. However, the improved ATES balance comes with a higher energy consumption cost of 12.5% when comparing the relative cost of the Cool 2.0 reward to the zero reward, resulting in a trade-off. Moreover, the method comes with limited requirements and is applicable to any long-term problem satisfying a linear state-transition system.

关键词： Data centers ATES Smart energy systems Reinforcement learning Delayed rewards

来源：评论

学校读者我要写书评

暂无评论

ILAPU-Q: An Improved Lightweight Authentication Protocol for IoT Based on U-quark Hash Function

引用

Recent Advances in computer science and Communications 2024年第2期17卷 78-87页

作者： Jebrane, Jihane Lazaar, Saiida Mathematics and Computer Science Department Mathematics Computer Science and Applications ERMIA-Team National School of Applied Science-ENSA of Tangier AbdelMalek Essaadi University Tetouan Morocco

Background: In the last decades, the development of Internet activities has been significantly accelerated, particularly with the emergence of the Internet of Things (IoT). Heterogeneous devices in the IoT can seamlessly and feasibly inter-connect with each other with-out human interaction. Due to this revolution, many applications have been adopted in the are-na of smart healthcare, e-commerce, environmental and habitat monitoring, etc. In order to promote and facilitate people's standards of living around the world. However, these unbound-ed applications bring more challenges to the storage capabilities of devices, and their security and privacy preservation. Moreover, security issues suffer from weak authentication protocols. Methods: To address these issues, suitable and secure lightweight mutual authentication schemes based on Elliptic Curve Cryptography (ECC) are required for the approval of Identity Management (IDM) of devices in the IoT. In this paper, we will propose an improved mutual authentication scheme based on ECC, coupled with a relevant seminal work considered as a reference in the field. This scheme is combined with U-quark, a lightweight hash function, to guarantee the security needed in the IoT environment. Results: We will compare our amended protocol with a seminal scheme as an established reference in terms of computation cost, storage cost, and executing CPU time to demonstrate that our version can ensure the most favorable performance during the authentication process. Conclusion: Finally, our proposed mutual authentication scheme has demonstrated its effectiveness in enhancing the security of IoT devices when compared to the seminal work in the same computational environment. © 2024, Bentham science Publishers. All rights reserved.

关键词： Hash functions

来源：评论

学校读者我要写书评

暂无评论

Quantum spin systems: Toroidal classification and geometric duality

引用

Physical Review B 2024年第14期110卷 L140403页

作者： Vahid Azimi-Mousolou Anders Bergman Anna Delin Olle Eriksson Manuel Pereiro Danny Thonig Erik Sjöqvist Department of Applied Mathematics and Computer Science Faculty of Mathematics and Statistics Department of Physics and Astronomy Department of Applied Physics School of Engineering Sciences (SeRC) Wallenberg Initiative Materials Science for Sustainability (WISE) Wallenberg Initiative Materials Science WISE School of Science and Technology

We demonstrate a toroidal classification for quantum spin systems, revealing an intrinsic geometric duality within this structure. Through our classification and duality, we reveal that various bipartite quantum features in magnon systems can manifest equivalently in both bipartite ferromagnetic and antiferromagnetic materials, based upon the availability of relevant Hamiltonian parameters. Additionally, the results highlight the antiferromagnetic regime as an ultrafast dual counterpart to the ferromagnetic regime, both exhibiting identical capabilities for quantum spintronics and technological applications. Concrete illustrations are provided, demonstrating how splitting and squeezing types of two-mode magnon quantum correlations can be realized across ferro- and antiferromagnetic regimes.

关键词： Magnons Quantum correlations in quantum information Quantum information processing Quantum information theory Spintronics

来源：评论

学校读者我要写书评

暂无评论

Modified DS np Chart Using Generalized Multiple Dependent State Sampling under Time Truncated Life Test

引用

computer Modeling in Engineering & sciences 2024年第3期138卷 2471-2495页

作者： Wimonmas Bamrungsetthapong Pramote Charongrattanasakul Division of Applied Statistics Department of Mathematics and Computer ScienceFaculty of Science and TechnologyRajamangala University of Technology ThanyaburiPathum Thani12110Thailand Division of Mathematics Department of Mathematics and Computer ScienceFaculty of Science and TechnologyRajamangala University of Technology KrungthepBangkok10120Thailand

This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of the product based on the time truncated life test employing theWeibull *** control chart developed supports the examination of the mean lifespan variation for a particular product in the process of *** control limit levels are used:the warning control limit,inner control limit,and outer control ***,they enhance the capability for variation detection.A genetic algorithm can be used for optimization during the in-control process,whereby the optimal parameters can be established for the proposed control *** control chart performance is assessed using the average run length,while the influence of the model parameters upon the control chart solution is assessed via sensitivity analysis based on an orthogonal experimental design withmultiple linear regression.A comparative study was conducted based on the out-of-control average run length,in which the developed control chart offered greater sensitivity in the detection of process shifts while making use of smaller samples on average than is the case for existing control ***,to exhibit the utility of the developed control chart,this paper presents its application using simulated data with parameters drawn from the real set of data.

关键词： Modified DS np chart generalizedmultiple dependent state sampling time truncated life test Weibull distribution average run length average sample size

来源：评论

学校读者我要写书评

暂无评论

An infrastructure software perspective toward computation offloading between executable specifications and foundation models

引用

science China(Information sciences) 2025年第4期68卷 380-382页

作者： Dezhi RAN Mengzhou WU Yuan CAO Assaf MARRON David HAREL Tao XIE Key Laboratory of High Confidence Software Technologies (PKU) Ministry of Education School of Computer SciencePeking University School of Electronics Engineering and Computer Science Peking University Department of Computer Science and Applied Mathematics Weizmann Institute of Science

Foundation models(FMs) [1] have revolutionized software development and become the core components of large software systems. This paradigm shift, however, demands fundamental re-imagining of software engineering theories and methodologies [2]. Instead of replacing existing software modules implemented by symbolic logic, incorporating FMs' capabilities to build software systems requires entirely new modules that leverage the unique capabilities of ***, while FMs excel at handling uncertainty, recognizing patterns, and processing unstructured data, we need new engineering theories that support the paradigm shift from explicitly programming and maintaining user-defined symbolic logic to creating rich, expressive requirements that FMs can accurately perceive and implement.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Integrating Distributed Flexibility into TSO-DSO Coordinated Electricity Markets

IEEE Transactions on Energy Markets, Policy and Regulation

引用

IEEE Transactions on Energy Markets, Policy and Regulation 2024年第2期2卷 214-225页

作者： Tsaousoglou, Georgios Junker, Rune Banaei, Mohsen Tohidi, Seyed Shahabaldin Madsen, Henrik Technical University of Denmark Department of Applied Mathematics Computer Science Lyngby2800 Denmark

The future of electricity markets is envisioned to be heavily based on renewable generation and distributed flexibility. Yet, integrating existing distributed flexibility into market decisions poses a major challenge, given the diversity of consumers' modeling frameworks and controllers. Moreover, in such a system, the market's decisions need to be predictive, adaptive, as well as TSO-DSO coordinated. In this article, we present an iterative market procedure through which, in contrast to traditional electricity markets based on one-off bids, flexible participants can indirectly implement their model by repeatedly responding to tentative pricing signals. This, combined with a scheduling/forecasting grey-box agent introduced on the consumer side, allows for the seamless integration of existing flexible loads' control schemes into a holistic electricity market. The proposed market-operation policy inherently coordinates Transmission and Distribution System Operators' decisions in the presence of uncertain distributed flexibility and renewables' generation. The results demonstrate promising convergence properties and short execution times, which is encouraging towards the scheme's practical applicability. © 2023 IEEE.

关键词： Power markets

来源：评论

学校读者我要写书评

暂无评论

DP-ARTS: Dynamic Prioritization for Adaptive Resource Allocation and Task Scheduling in Cloud Computing

IAENG International Journal of Computer Science

引用

IAENG International Journal of computer science 2025年第3期52卷 793-807页

作者： BEN ALLA, Hicham BEN ALLA, Said EZZATI, Abdellah Computer Science Mathematics and Computer Science Department Science and Technical Faculty Hassan 1 University Settat Morocco Embedded Systems and Computer Science National School of Applied Sciences of Berrechid Hassan 1 University Settat Morocco

Efficient task scheduling and resource allocation are essential for optimizing performance in cloud computing environments. The presence of priority constraints necessitates advanced solutions capable of addressing the increased complexity in the task scheduling process and resource allocation management. In this paper, we propose a novel approach, Dynamic Prioritization and Adaptive Resource Allocation and Task Scheduling (DP-ARTS), to tackle these challenges by integrating dynamic task prioritization with adaptive resource allocation and scheduling strategies. Our approach introduces a scoring mechanism to prioritize tasks based on deadlines, resource requirements, and other critical characteristics. Furthermore, we utilize K-means clustering to group Virtual Machines (VMs) according to their capabilities, facilitating more efficient task-to-VM mapping. Through simulations conducted with real-world workload traces in the CloudSim toolkit, DP-ARTS demonstrates superior performance in reducing makespan and energy consumption, while also improving resource utilization and load balancing compared to existing solutions. © (2025), (International Association of Engineers). All rights reserved.

关键词： K-means clustering

来源：评论

学校读者我要写书评

暂无评论

Consensus Learning with Deep Sets for Essential Matrix Estimation 38

Consensus Learning with Deep Sets for Essential Matrix Estim...

引用

38th Conference on Neural Information Processing Systems, NeurIPS 2024

作者： Moran, Dror Margalit, Yuval Trostianetsky, Guy Khatib, Fadi Galun, Meirav Basri, Ronen Department of Computer Science and Applied Mathematics Weizmann Institute of Science Israel

Robust estimation of the essential matrix, which encodes the relative position and orientation of two cameras, is a fundamental step in structure from motion pipelines. Recent deep-based methods achieved accurate estimation by using complex network architectures that involve graphs, attention layers, and hard pruning steps. Here, we propose a simpler network architecture based on Deep Sets. Given a collection of point matches extracted from two images, our method identifies outlier point matches and models the displacement noise in inlier matches. A weighted DLT module uses these predictions to regress the essential matrix. Our network achieves accurate recovery that is superior to existing networks with significantly more complex architectures. © 2024 Neural information processing systems foundation. All rights reserved.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Simpler Optimal Sorting from a Directed Acyclic Graph 8

Simpler Optimal Sorting from a Directed Acyclic Graph

引用

8th SIAM Symposium on Simplicity of Algorithms, SOSA 2025

作者： van der Hoog, Ivor Rotenberg, Eva Rutschmann, Daniel Department of Applied Mathematics and Computer Science Technical University of Denmark Denmark

ISBN: (纸本)9781611978315

Fredman proposed in 1976 the following algorithmic problem: Given are a ground set X, some partial order P over X, and some comparison oracle OL that specifies a linear order L over X that extends P. A query to OL has as input distinct x, x′ ∈ X and outputs whether x ′ or vice versa. If we denote by e(P) the number of linear orders that extend P, then it follows from basic information theory that log e(P) is a worst-case lower bound on the number of queries needed to output the sorted order of X. Fredman did not specify in what form the partial order is given. Haeupler, Hladík, Iacono, Rozhon, Tarjan, and Tětek ('24) propose to assume as input a directed acyclic graph, G, with m edges and n = |X| vertices. Denote by PG the partial order induced by G. Their algorithmic performance is measured in running time and the number of queries used, where they use Θ(m + n + log e(PG)) time and Θ(log e(PG)) queries to output X in its sorted order. Their algorithm is worst-case optimal, both in terms of running time and queries. Their analysis relies upon sophisticated counting arguments using entropy, recursively defined sets defined over the run of their algorithm, and vertices in the graph that they identify as bottlenecks for sorting. We do away with sophistication. We show that when the input is a directed acyclic graph then the problem admits a simple solution using Θ(m + n + log e(PG)) time and Θ(log e(PG)) queries. Especially our proofs are much simpler as we avoid the usage of advanced charging arguments, and instead rely upon two observations. Copyright © 2025 by SIAM.

关键词： Directed graphs

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：