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Anomaly detection on displacement rates and deformation pattern features using tree-based algorithm in Japan and Indonesia 被引量:1
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作者 Adi Wibowo Satriawan Rasyid Purnama +3 位作者 Cecep Pratama Leni Sophia Heliani David P.Sahara Sidik Tri Wibowo 《Geodesy and Geodynamics》 CSCD 2023年第2期150-162,共13页
Research on strain anomalies and large earthquakes based on temporal and spatial crustal activities has been rapidly growing due to data availability, especially in Japan and Indonesia. However, many research works us... Research on strain anomalies and large earthquakes based on temporal and spatial crustal activities has been rapidly growing due to data availability, especially in Japan and Indonesia. However, many research works used local-scale case studies that focused on a specific earthquake characteristic using knowledgedriven techniques, such as crustal deformation analysis. In this study, a data-driven-based analysis is used to detect anomalies using displacement rates and deformation pattern features extracted from daily global navigation satellite system(GNSS) data using a machine learning algorithm. The GNSS data with188 and 1181 continuously operating reference stations from Indonesia and Japan, respectively, are used to identify the anomaly of recent major earthquakes in the last two decades. Feature displacement rates and deformation patterns are processed in several window times with 2560 experiment scenarios to produce the best detection using tree-based algorithms. Tree-based algorithms with a single estimator(decision tree), ensemble bagging(bagging, random forest and Extra Trees), and ensemble boosting(AdaBoost, gradient boosting, LGBM, and XGB) are applied in the study. The experiment test using realtime scenario GNSSdailydatareveals high F1-scores and accuracy for anomaly detection using slope windowing 365 and 730 days of 91-day displacement rates and then 7-day deformation pattern features in tree-based algorithms. The results show the potential for medium-term anomaly detection using GNSS data without the need for multiple vulnerability assessments. 展开更多
关键词 ANOMALY GNSS Displacement rates Deformation pattern tree-based algorithm
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SQL Server性能优化的技术分析
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作者 赵佳 《中国高新科技》 2024年第7期102-104,107,共4页
随着客户端/服务器技术和多层架构的进步,系统效率问题日益引发广泛讨论。由于缺乏数据库管理系统(DBMS)提供的优化方法和工具,以及基于微软技术的数据库管理员和应用程序开发人员的知识,无法对设计和服务执行系统进行优化。文章回顾了... 随着客户端/服务器技术和多层架构的进步,系统效率问题日益引发广泛讨论。由于缺乏数据库管理系统(DBMS)提供的优化方法和工具,以及基于微软技术的数据库管理员和应用程序开发人员的知识,无法对设计和服务执行系统进行优化。文章回顾了提高SQL Server实例性能时需要考虑的目标,并阐述了用于优化查询的技术。 展开更多
关键词 查询 优化 SQL server
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Python Server Page Performance Analysis and Modeling
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作者 Razafindraibe Marolahy Alix Randrianomenjanahary Lala Ferdinand +2 位作者 Rafamantanantsoa Fontaine Mahatody Thomas F. Angelo Raherinirina 《Communications and Network》 2024年第1期1-30,共30页
Today, in the field of computer networks, new services have been developed on the Internet or intranets, including the mail server, database management, sounds, videos and the web server itself Apache. The number of s... Today, in the field of computer networks, new services have been developed on the Internet or intranets, including the mail server, database management, sounds, videos and the web server itself Apache. The number of solutions for this server is therefore growing continuously, these services are becoming more and more complex and expensive, without being able to fulfill the needs of the users. The absence of benchmarks for websites with dynamic content is the major obstacle to research in this area. These users place high demands on the speed of access to information on the Internet. This is why the performance of the web server is critically important. Several factors influence performance, such as server execution speed, network saturation on the internet or intranet, increased response time, and throughputs. By measuring these factors, we propose a performance evaluation strategy for servers that allows us to determine the actual performance of different servers in terms of user satisfaction. Furthermore, we identified performance characteristics such as throughput, resource utilization, and response time of a system through measurement and modeling by simulation. Finally, we present a simple queue model of an Apache web server, which reasonably represents the behavior of a saturated web server using the Simulink model in Matlab (Matrix Laboratory) and also incorporates sporadic incoming traffic. We obtain server performance metrics such as average response time and throughput through simulations. Compared to other models, our model is conceptually straightforward. The model has been validated through measurements and simulations during the tests that we conducted. 展开更多
关键词 Performance Analysis QUEUE Performance Model Web server Internet World Wide Web Web server Performance
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FedAdaSS: Federated Learning with Adaptive Parameter Server Selection Based on Elastic Cloud Resources
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作者 Yuwei Xu Baokang Zhao +1 位作者 Huan Zhou Jinshu Su 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期609-629,共21页
The rapid expansion of artificial intelligence(AI)applications has raised significant concerns about user privacy,prompting the development of privacy-preserving machine learning(ML)paradigms such as federated learnin... The rapid expansion of artificial intelligence(AI)applications has raised significant concerns about user privacy,prompting the development of privacy-preserving machine learning(ML)paradigms such as federated learning(FL).FL enables the distributed training of ML models,keeping data on local devices and thus addressing the privacy concerns of users.However,challenges arise from the heterogeneous nature of mobile client devices,partial engagement of training,and non-independent identically distributed(non-IID)data distribution,leading to performance degradation and optimization objective bias in FL training.With the development of 5G/6G networks and the integration of cloud computing edge computing resources,globally distributed cloud computing resources can be effectively utilized to optimize the FL process.Through the specific parameters of the server through the selection mechanism,it does not increase the monetary cost and reduces the network latency overhead,but also balances the objectives of communication optimization and low engagement mitigation that cannot be achieved simultaneously in a single-server framework of existing works.In this paper,we propose the FedAdaSS algorithm,an adaptive parameter server selection mechanism designed to optimize the training efficiency in each round of FL training by selecting the most appropriate server as the parameter server.Our approach leverages the flexibility of cloud resource computing power,and allows organizers to strategically select servers for data broadcasting and aggregation,thus improving training performance while maintaining cost efficiency.The FedAdaSS algorithm estimates the utility of client systems and servers and incorporates an adaptive random reshuffling strategy that selects the optimal server in each round of the training process.Theoretical analysis confirms the convergence of FedAdaSS under strong convexity and L-smooth assumptions,and comparative experiments within the FLSim framework demonstrate a reduction in training round-to-accuracy by 12%–20%compared to the Federated Averaging(FedAvg)with random reshuffling method under unique server.Furthermore,FedAdaSS effectively mitigates performance loss caused by low client engagement,reducing the loss indicator by 50%. 展开更多
关键词 Machine learning systems federated learning server selection artificial intelligence of things non-IID data
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A Design of an SMTP Email Server
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作者 Liheng Hu 《Journal of Electronic Research and Application》 2024年第4期41-47,共7页
This study developed a mail server program using Socket API and Python.The program uses the Hypertext Transfer Protocol(HTTP)to receive emails from browser clients and forward them to actual email service providers vi... This study developed a mail server program using Socket API and Python.The program uses the Hypertext Transfer Protocol(HTTP)to receive emails from browser clients and forward them to actual email service providers via the Simple Mail Transfer Protocol(SMTP).As a web server,it handles Transmission Control Protocol(TCP)connection requests from browsers,receives HTTP commands and email data,and temporarily stores the emails in a file.Simultaneously,as an SMTP client,the program establishes a TCP connection with the actual mail server,sends SMTP commands,and transmits the previously saved emails.In addition,we also analyzed security issues and the efficiency and availability of this server,providing insights into the design of SMTP mail servers. 展开更多
关键词 Mail server Socket API HTTP protocol SMTP protocol Security analysis Efficiency analysis
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Excel+SQL Server在实验成绩信息管理中的应用研究
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作者 舒鹏丽 高平 白心爱 《电脑编程技巧与维护》 2024年第3期107-109,共3页
深入探讨了如何利用Excel和SQL Server集成化地管理和分析大学物理实验成绩信息。通过建立数据库、导入导出数据、数据查询与分析及使用Excel的数据透视表和图表功能,可以高效地管理实验成绩数据,进而深入分析学生的学习情况和教学效果。
关键词 EXCEL表格 SQL server数据库 实验成绩 数据
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基于ArcGIS Server的网络农田地理信息系统设计 被引量:1
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作者 阮国杰 师倩 《智慧农业导刊》 2023年第15期45-48,共4页
该文为提高农田信息管理智能化水平,应用ArcGIS Server应用平台,完成对网络农田地理信息系统的设计。首先,设计和搭建系统架构和系统运行环境。其次,分别设计用户登录、信息表达、查询统计、专题图制作和空间分析等模块,保证系统功能设... 该文为提高农田信息管理智能化水平,应用ArcGIS Server应用平台,完成对网络农田地理信息系统的设计。首先,设计和搭建系统架构和系统运行环境。其次,分别设计用户登录、信息表达、查询统计、专题图制作和空间分析等模块,保证系统功能设计效果。最后,从应用层、服务层、数据层3个方面,完成对系统设计和实现。结果表明,在ArcGIS Server应用平台的应用背景下,该文所设计的网络农田地理信息系统具有操作简单、安全可靠等特点,可以实时共享和发布农田空间信息,完全符合预期设计标准和要求。希望通过这次研究,为相关人员提供有效的借鉴和参考。 展开更多
关键词 ArcGIS server 网络农田地理信息系统 农田地理信息 系统设计 农田信息化建设
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Tree-Based Proactive Routing Protocol for Wireless Mesh Network 被引量:2
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作者 Ji Wenjiang Ma Jianfeng +1 位作者 Ma Zhuo Ran Youliang 《China Communications》 SCIE CSCD 2012年第1期25-33,共9页
Wireless Mesh Network (WMN) is seen as an effective Intemet access solution for dynamic wireless applications. For the low mobility of mesh routers in WMN, the backbone topography can be effectively maintained by pr... Wireless Mesh Network (WMN) is seen as an effective Intemet access solution for dynamic wireless applications. For the low mobility of mesh routers in WMN, the backbone topography can be effectively maintained by proactive routing protocol. Pre-proposals like Tree Based Routing (TBR) protocol and Root Driven Routing (RDR) protocol are so centralized that they make the gateway becorre a bottleneck which severely restricts the network performance. We proposed an Optimized Tree-based Routing (OTR) protocol that logically separated the proactive tree into pieces. Route is partly computed by the branches instead of root. We also discussed the operation of multipie Intemet gateways which is a main issue in WMN. The new proposal lightens the load in root, reduces the overhead and improves the throughput. Numerical analysis and simulation results confirm that the perforrmnce of WMN is improved and OTR is more suitable for large scale WMN. 展开更多
关键词 wireless mesh network 802. lls routing protocol tree-based routing
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基于FreeRTOS的多连接TCP Server设计 被引量:1
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作者 范亚南 高军科 +1 位作者 韩文斌 魏亚伟 《仪表技术与传感器》 CSCD 北大核心 2023年第8期96-100,共5页
文中提出了一种支持多客户端连接的TCP Server的嵌入式软硬件设计方案。该网络服务器以Cortex-M4芯片STM32F407VET6为核心控制器,通过RMII接口与LAN8742A以太网收发器进行网络数据交互。此外,文中将LwIP协议栈移植到FreeRTOS实时操作系... 文中提出了一种支持多客户端连接的TCP Server的嵌入式软硬件设计方案。该网络服务器以Cortex-M4芯片STM32F407VET6为核心控制器,通过RMII接口与LAN8742A以太网收发器进行网络数据交互。此外,文中将LwIP协议栈移植到FreeRTOS实时操作系统中,并根据TCP客户端连接情况,动态创建或消除相应客户端的网络通信线程。研究证明,TCP Server最大可支持4个客户端同时连接,进行稳定的网络数据传输,有效解决了嵌入式网络系统仅单点连接的问题。 展开更多
关键词 FREERTOS STM32F407 多连接TCP server
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Immunizations on small worlds of tree-based wireless sensor networks 被引量:1
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作者 李峤 张百海 +2 位作者 崔灵果 范衠 Athanasios V.Vasilakos 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期25-33,共9页
The sensor virus is a serious threat,as an attacker can simply send a single packet to compromise the entire sensor network.Epidemics become drastic with link additions among sensors when the small world phenomena occ... The sensor virus is a serious threat,as an attacker can simply send a single packet to compromise the entire sensor network.Epidemics become drastic with link additions among sensors when the small world phenomena occur.Two immunization strategies,uniform immunization and temporary immunization,are conducted on small worlds of tree-based wireless sensor networks to combat the sensor viruses.With the former strategy,the infection extends exponentially,although the immunization effectively reduces the contagion speed.With the latter strategy,recurrent contagion oscillations occur in the small world when the spatial-temporal dynamics of the epidemic are considered.The oscillations come from the small-world structure and the temporary immunization.Mathematical analyses on the small world of the Cayley tree are presented to reveal the epidemic dynamics with the two immunization strategies. 展开更多
关键词 epidemic immunization small world tree-based networks
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Classes of tree-based networks 被引量:1
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作者 Mareike Fischer Michelle Galla +2 位作者 Lina Herbst Yangjing Long Kristina Wicke 《Visual Computing for Industry,Biomedicine,and Art》 2020年第1期104-129,共26页
Recently,so-called tree-based phylogenetic networks have attracted considerable attention.These networks can be constructed from a phylogenetic tree,called the base tree,by adding additional edges.The primary aim of t... Recently,so-called tree-based phylogenetic networks have attracted considerable attention.These networks can be constructed from a phylogenetic tree,called the base tree,by adding additional edges.The primary aim of this study is to provide sufficient criteria for tree-basedness by reducing phylogenetic networks to related graph structures.Even though it is generally known that determining whether a network is tree-based is an NP-complete problem,one of these criteria,namely edge-basedness,can be verified in linear time.Surprisingly,the class of edgebased networks is closely related to a well-known family of graphs,namely,the class of generalized series-parallel graphs,and we explore this relationship in full detail.Additionally,we introduce further classes of tree-based networks and analyze their relationships. 展开更多
关键词 Phylogenetic tree Phylogenetic network tree-based network Edge-based network Chordal network Hamilton connected Hamiltonian path Generalized series-parallel graphs Series-parallel graphs
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基于SQL Server的教学评价管理系统设计 被引量:1
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作者 肖宁 周琴 +2 位作者 胡方宇 刘翰林 包泯轩 《无线互联科技》 2023年第20期46-49,共4页
教学评价是教学工作中的重要环节,传统的教学评价方式难以实现对学生学习过程性评价的及时存储及更新,存在时效性不高、难以量化的问题,很难依据评价实现对学生学习行为的及时指导。文章主要针对传统教学评价存在的以上问题,综合使用SQL... 教学评价是教学工作中的重要环节,传统的教学评价方式难以实现对学生学习过程性评价的及时存储及更新,存在时效性不高、难以量化的问题,很难依据评价实现对学生学习行为的及时指导。文章主要针对传统教学评价存在的以上问题,综合使用SQL Server开发平台设计了一套便捷、高效的教学评价管理系统,实现了混合式教学中相关教学数据的实时增删改查基本功能以及教学评价与管理等功能,从而实现对学生学业的多维过程性评价,进而指导教学。 展开更多
关键词 SQL server 管理系统 教学评价
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基于改进Apriori算法的SQL Server数据库入侵识别方法 被引量:1
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作者 王春平 杨柳 《信息与电脑》 2023年第13期197-199,共3页
常规的数据库入侵识别方法以识别入侵行为数据为主,各种识别模块导致数据库入侵识别的恶意操作增加。因此,设计了基于改进Apriori算法的SQL Server数据库入侵识别方法。首先,识别SQL Server数据库入侵类型,将数据库中的关键词进行条件... 常规的数据库入侵识别方法以识别入侵行为数据为主,各种识别模块导致数据库入侵识别的恶意操作增加。因此,设计了基于改进Apriori算法的SQL Server数据库入侵识别方法。首先,识别SQL Server数据库入侵类型,将数据库中的关键词进行条件查询判断。其次,提取入侵攻击的语句特征,避免附加语句执行恶意操作。最后,基于改进Apriori算法迭代数据库的频繁项集,通过逐层识别的形式迭代寻找SQL Server数据库中所有项集的关系,并形成识别规则,提升了数据库入侵识别性能。 展开更多
关键词 改进Apriori算法 SQL server数据库 入侵 识别方法
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基于Java和SQL Server的仓库管理系统的设计与开发 被引量:5
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作者 司小龙 《科技创新与生产力》 2023年第1期71-74,77,共5页
本文针对依靠大量人力、物力的传统管理模式存在的缺陷,以药品的仓库管理为例,采用Java语言和SQL Server数据库,设计并开发了一套精准、高效、便捷的仓库管理系统。分析了系统的业务需求和功能需求,从功能设计和数据库设计两个方面设计... 本文针对依靠大量人力、物力的传统管理模式存在的缺陷,以药品的仓库管理为例,采用Java语言和SQL Server数据库,设计并开发了一套精准、高效、便捷的仓库管理系统。分析了系统的业务需求和功能需求,从功能设计和数据库设计两个方面设计了系统的总体方案,实现了系统的可视化图形用户界面、数据库功能、入库功能、出库功能。 展开更多
关键词 仓库管理系统 JAVA SQL server 系统需求 系统实现
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Code Clone Detection Method Based on the Combination of Tree-Based and Token-Based Methods
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作者 Ryota Ami Hirohide Haga 《Journal of Software Engineering and Applications》 2017年第13期891-906,共16页
This article proposes the high-speed and high-accuracy code clone detection method based on the combination of tree-based and token-based methods. Existence of duplicated program codes, called code clone, is one of th... This article proposes the high-speed and high-accuracy code clone detection method based on the combination of tree-based and token-based methods. Existence of duplicated program codes, called code clone, is one of the main factors that reduces the quality and maintainability of software. If one code fragment contains faults (bugs) and they are copied and modified to other locations, it is necessary to correct all of them. But it is not easy to find all code clones in large and complex software. Much research efforts have been done for code clone detection. There are mainly two methods for code clone detection. One is token-based and the other is tree-based method. Token-based method is fast and requires less resources. However it cannot detect all kinds of code clones. Tree-based method can detect all kinds of code clones, but it is slow and requires much computing resources. In this paper combination of these two methods was proposed to improve the efficiency and accuracy of detecting code clones. Firstly some candidates of code clones will be extracted by token-based method that is fast and lightweight. Then selected candidates will be checked more precisely by using tree-based method that can find all kinds of code clones. The prototype system was developed. This system accepts source code and tokenizes it in the first step. Then token-based method is applied to this token sequence to find candidates of code clones. After extracting several candidates, selected source codes will be converted into abstract syntax tree (AST) for applying tree-based method. Some sample source codes were used to evaluate the proposed method. This evaluation proved the improvement of efficiency and precision of code clones detecting. 展开更多
关键词 Code Clone Token-Based DETECTION tree-based DETECTION TREE EDIT Distance
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Mobile Edge Computing Servers Deployment with Improved Genetic Algorithm in Cellular Internet of Things 被引量:1
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作者 Huan Zhang Junhui Zhao +1 位作者 Lihua Yang Ziyang Zhang 《China Communications》 SCIE CSCD 2023年第9期215-226,共12页
Mobile edge computing(MEC)provides services to devices and reduces latency in cellular internet of things(IoT)networks.However,the challenging problem is how to deploy MEC servers economically and efficiently.This pap... Mobile edge computing(MEC)provides services to devices and reduces latency in cellular internet of things(IoT)networks.However,the challenging problem is how to deploy MEC servers economically and efficiently.This paper investigates the deployment problem of MEC servers of the real-world road network by employing an improved genetic algorithm(GA)scheme.We first use the threshold-based K-means algorithm to form vehicle clusters according to their locations.We then select base stations(BSs)based on clustering center coordinates as the deployment locations set for potential MEC servers.We further select BSs using a combined simulated annealing(SA)algorithm and GA to minimize the deployment cost.The simulation results show that the improved GA deploys MEC servers effectively.In addition,the proposed algorithm outperforms GA and SA algorithms in terms of convergence speed and solution quality. 展开更多
关键词 deployment of MEC servers IoT im-proved GA COST
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基于SQL server的生产管理系统数据库设计研究 被引量:2
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作者 王思阳 《科学与信息化》 2023年第10期78-80,共3页
计算机市场瞬息万变,信息的收集、综合和分析至关重要。无法实时评估公司的销售和卖家的销售结果可能会导致公司高管在决策和分析过程中出现延误或误解,从而对公司的底线和增长产生重大影响。销售管理也是公司ERP的重要组成部分,是企业... 计算机市场瞬息万变,信息的收集、综合和分析至关重要。无法实时评估公司的销售和卖家的销售结果可能会导致公司高管在决策和分析过程中出现延误或误解,从而对公司的底线和增长产生重大影响。销售管理也是公司ERP的重要组成部分,是企业信息化的标志。本文以SQL server为基础,提出一种生产管理系统数据库设计方法,以供参考。 展开更多
关键词 SQL server 生产管理系统 数据库设计
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The Research of Role Tree-Based Access Control Model
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作者 陆虹 夏天 《Journal of Donghua University(English Edition)》 EI CAS 2010年第2期274-276,共3页
Towards the crossing and coupling permissions in tasks existed widely in many fields and considering the design of role view must rely on the activities of the tasks process,based on Role Based Accessing Control (RBAC... Towards the crossing and coupling permissions in tasks existed widely in many fields and considering the design of role view must rely on the activities of the tasks process,based on Role Based Accessing Control (RBAC) model,this paper put forward a Role Tree-Based Access Control (RTBAC) model. In addition,the model definition and its constraint formal description is also discussed in this paper. RTBAC model is able to realize the dynamic organizing,self-determination and convenience of the design of role view,and guarantee the least role permission when task separating in the mean time. 展开更多
关键词 Role Based Accessing Control (RBAC) Role tree-based Access Control (RTBAC) Models Constraints Permission
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A Statistical Analysis of Textual E-Commerce Reviews Using Tree-Based Methods
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作者 Jessica Kubrusly Ana Luiza Neves Thamires Louzada Marques 《Open Journal of Statistics》 2022年第3期357-372,共16页
With the increasing interest in e-commerce shopping, customer reviews have become one of the most important elements that determine customer satisfaction regarding products. This demonstrates the importance of working... With the increasing interest in e-commerce shopping, customer reviews have become one of the most important elements that determine customer satisfaction regarding products. This demonstrates the importance of working with Text Mining. This study is based on The Women’s Clothing E-Commerce Reviews database, which consists of reviews written by real customers. The aim of this paper is to conduct a Text Mining approach on a set of customer reviews. Each review was classified as either a positive or negative review by employing a classification method. Four tree-based methods were applied to solve the classification problem, namely Classification Tree, Random Forest, Gradient Boosting and XGBoost. The dataset was categorized into training and test sets. The results indicate that the Random Forest method displays an overfitting, XGBoost displays an overfitting if the number of trees is too high, Classification Tree is good at detecting negative reviews and bad at detecting positive reviews and the Gradient Boosting shows stable values and quality measures above 77% for the test dataset. A consensus between the applied methods is noted for important classification terms. 展开更多
关键词 Text Mining Supervised Classification tree-based Methods Classification Trees Random Forest Gradient Boosting XGBoost
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Adaptive Load Balancing for Parameter Servers in Distributed Machine Learning over Heterogeneous Networks 被引量:1
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作者 CAI Weibo YANG Shulin +2 位作者 SUN Gang ZHANG Qiming YU Hongfang 《ZTE Communications》 2023年第1期72-80,共9页
In distributed machine learning(DML)based on the parameter server(PS)architecture,unbalanced communication load distribution of PSs will lead to a significant slowdown of model synchronization in heterogeneous network... In distributed machine learning(DML)based on the parameter server(PS)architecture,unbalanced communication load distribution of PSs will lead to a significant slowdown of model synchronization in heterogeneous networks due to low utilization of bandwidth.To address this problem,a network-aware adaptive PS load distribution scheme is proposed,which accelerates model synchronization by proactively adjusting the communication load on PSs according to network states.We evaluate the proposed scheme on MXNet,known as a realworld distributed training platform,and results show that our scheme achieves up to 2.68 times speed-up of model training in the dynamic and heterogeneous network environment. 展开更多
关键词 distributed machine learning network awareness parameter server load distribution heterogeneous network
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