期刊文献+
共找到4,552篇文章
< 1 2 228 >
每页显示 20 50 100
Habits on Social Networks at Workplace: A Survey of Motivations and Behaviour
1
作者 Thomas Kakou Kouassi Douatia Koné +3 位作者 Aliou Bamba Aladji Kamagaté Olivier Asseu Yvon Kermarrec 《Open Journal of Applied Sciences》 2024年第8期2154-2168,共15页
This article explores the use of social networks by workers in Abidjan, Côte d’Ivoire, with particular emphasis on a descriptive or quantitative analysis aimed at understanding motivations and methods of use. Mo... This article explores the use of social networks by workers in Abidjan, Côte d’Ivoire, with particular emphasis on a descriptive or quantitative analysis aimed at understanding motivations and methods of use. More than five hundred and fifty questionnaires were distributed, highlighting workers’ preferred digital channels and platforms. The results indicate that the majority use social media through their mobile phones, with WhatsApp being the most popular app, followed by Facebook and LinkedIn. The study reveals that workers use social media for entertainment purposes and to develop professional and social relationships, with 55% unable to live without social media at work for recreational activities. In addition, 35% spend on average 1 to 2 hours on social networks, mainly between 12 p.m. and 2 p.m. It also appears that 46% believe that social networks moderately improve their productivity. These findings can guide marketing strategies, training, technology development and government policies related to the use of social media in the workplace. 展开更多
关键词 Social network Social Media Applications Poisson’s Law STATISTICS Digital supports Workers Productivity
下载PDF
One-pot synthesis of network supported catalyst using supramolecular gel as template 被引量:2
2
作者 Yong Liang Li Ming Tang Yu Xia Kai Chen Bo Tian Li Xin Jin 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第8期991-994,共4页
A simple and general strategy is described for preparing network supported catalyst through a one-pot synthetic procedure using supramolecular gel as template.This procedure directly attaches ligand to support during ... A simple and general strategy is described for preparing network supported catalyst through a one-pot synthetic procedure using supramolecular gel as template.This procedure directly attaches ligand to support during fabricating the support.Using this strategy,supported CuBr/di-(2-picolyl) amine catalyst with U-shaped fibrillar network was prepared and used in atom transfer radical polymerization of methyl methacrylate.XPS and SEM characterization of the catalyst revealed homogeneous distribution of ligand,sufficient reactive sites,adequate mechanical strength and macroporosity.The polymerization results demonstrated high activity and reusability of such catalyst.This strategy might be extended to other supported catalysts used in column reactors. 展开更多
关键词 One-pot synthesis network supported catalyst Supramolecular gel Atom transfer radical polymerization
下载PDF
Design of Distributed Authentication Mechanism for Equipment Support Information Network 被引量:1
3
作者 晏杰 卢昱 +1 位作者 陈立云 王昌盛 《Journal of Donghua University(English Edition)》 EI CAS 2016年第2期266-271,共6页
Considering the secure authentication problem for equipment support information network,a clustering method based on the business information flow is proposed. Based on the proposed method,a cluster-based distributed ... Considering the secure authentication problem for equipment support information network,a clustering method based on the business information flow is proposed. Based on the proposed method,a cluster-based distributed authentication mechanism and an optimal design method for distributed certificate authority( CA)are designed. Compared with some conventional clustering methods for network,the proposed clustering method considers the business information flow of the network and the task of the network nodes,which can decrease the communication spending between the clusters and improve the network efficiency effectively. The identity authentication protocols between the nodes in the same cluster and in different clusters are designed. From the perspective of the security of network and the availability of distributed authentication service,the definition of the secure service success rate of distributed CA is given and it is taken as the aim of the optimal design for distributed CA. The efficiency of providing the distributed certificate service successfully by the distributed CA is taken as the constraint condition of the optimal design for distributed CA. The determination method for the optimal value of the threshold is investigated. The proposed method can provide references for the optimal design for distributed CA. 展开更多
关键词 equipment support information network identity authentication distributed certificate authority(CA) CLUSTERING threshold optimization
下载PDF
XML-based Data Processing in Network Supported Collaborative Design 被引量:2
4
作者 Qi Wang Zhong-Wei Ren Zhong-Feng Guo 《International Journal of Automation and computing》 EI 2010年第3期330-335,共6页
In the course of network supported collaborative design, the data processing plays a very vital role. Much effort has been spent in this area, and many kinds of approaches have been proposed. Based on the correlative ... In the course of network supported collaborative design, the data processing plays a very vital role. Much effort has been spent in this area, and many kinds of approaches have been proposed. Based on the correlative materials, this paper presents extensible markup language (XML) based strategy for several important problems of data processing in network supported collaborative design, such as the representation of standard for the exchange of product model data (STEP) with XML in the product information expression and the management of XML documents using relational database. The paper gives a detailed exposition on how to clarify the mapping between XML structure and the relationship database structure and how XML-QL queries can be translated into structured query language (SQL) queries. Finally, the structure of data processing system based on XML is presented. 展开更多
关键词 Extensible markup language (XML) network supported collaborative design standard for the exchange of product model data (STEP) data analysis data processing relational database
下载PDF
Comparison of School Building Construction Costs Estimation Methods Using Regression Analysis, Neural Network, and Support Vector Machine 被引量:2
5
作者 Gwang-Hee Kim Jae-Min Shin +1 位作者 Sangyong Kim Yoonseok Shin 《Journal of Building Construction and Planning Research》 2013年第1期1-7,共7页
Accurate cost estimation at the early stage of a construction project is key factor in a project’s success. But it is difficult to quickly and accurately estimate construction costs at the planning stage, when drawin... Accurate cost estimation at the early stage of a construction project is key factor in a project’s success. But it is difficult to quickly and accurately estimate construction costs at the planning stage, when drawings, documentation and the like are still incomplete. As such, various techniques have been applied to accurately estimate construction costs at an early stage, when project information is limited. While the various techniques have their pros and cons, there has been little effort made to determine the best technique in terms of cost estimating performance. The objective of this research is to compare the accuracy of three estimating techniques (regression analysis (RA), neural network (NN), and support vector machine techniques (SVM)) by performing estimations of construction costs. By comparing the accuracy of these techniques using historical cost data, it was found that NN model showed more accurate estimation results than the RA and SVM models. Consequently, it is determined that NN model is most suitable for estimating the cost of school building projects. 展开更多
关键词 ESTIMATING Construction COSTS Regression Analysis NEURAL network support VECTOR MACHINE
下载PDF
IS YOUR NETWORK SUPPORTING YOUR TERMINALS? OR IS IT THE OTHER WAY AROUND?
6
《ZTE Communications》 2006年第4期69-69,共1页
关键词 IT ZTE IS YOUR network supportING YOUR TERMINALS
下载PDF
IS YOUR NETWORK SUPPORTING YOUR TERMINALS? OR IS IT THE OTHER WAY AROUND?
7
《ZTE Communications》 2007年第2期70-70,共1页
Both,actually.That’s why ZTE provides not only network solutions,but also terminals that work as integral parts of optimised systems.
关键词 ZTE IT IS YOUR network supportING YOUR TERMINALS
下载PDF
IS YOUR NETWORK SUPPORTING YOUR TERMINALS? OR IS IT THE OTHER WAY AROUND?
8
《ZTE Communications》 2007年第4期62-62,共1页
Both, actually. That’s why ZTE provides not only network solutions, but also terminals that work as integral parts of
关键词 ZTE IS YOUR network supportING YOUR TERMINALS OR IS IT THE OTHER WAY AROUND IT
下载PDF
IS YOUR NETWORK SUPPORTING YOUR TERMINALS? OR IS IT THE OTHER WAY AROUND?
9
《ZTE Communications》 2007年第3期64-64,共1页
Both,actually.That’s why ZTE provides not only network solutions,but also terminals that work as integral parts of optimised systems.
关键词 ZTE IS YOUR network supportING YOUR TERMINALS OR IS IT THE OTHER WAY AROUND IT
下载PDF
Overvoltage Identification in Distribution Networks Based on Support Vector Machine 被引量:2
10
作者 DU Lin DAI Bin +2 位作者 SIMA Wen-xia LEI Jing CHEN Ming 《高电压技术》 EI CAS CSCD 北大核心 2009年第3期521-526,共6页
关键词 电压在线监测系统 电压波形 支持向量机 计算方法 供电技术
下载PDF
Wireless Network Technologies Supporting M2M Applications
11
作者 Lei Zhenzhou (China Academy of Telecommunications Research of Mil, Beijing 100083, China) 《ZTE Communications》 2005年第1期6-9,共4页
When computers and communication devices are available everywhere in the future, the categories of communication will expand to cover not only the man-man and the man-machine, but also the machine-machine (M2M) commun... When computers and communication devices are available everywhere in the future, the categories of communication will expand to cover not only the man-man and the man-machine, but also the machine-machine (M2M) communication. Someday, the traffic generated by machines will greatly exceed those of man-machine and man-man applications. Large numbers of M2M applications will need various wireless networks to support them. This paper introduces the characteristics, advantages and disadvantages of the currently available various wireless network technologies, including WiFi, Bluetooth, ZigBee, passive RFID and the 802.15 standard networks. 展开更多
关键词 ZIGBEE UWB Wireless network Technologies supporting M2M Applications RFID WiFi
下载PDF
Prioritizing Maintenance Spare Parts Based on Supportability Analysis and Neural Network
12
作者 胡起伟 贾希胜 +1 位作者 白永生 田霞 《Journal of Donghua University(English Edition)》 EI CAS 2015年第6期965-969,共5页
In order to facilitate spare parts management,an integrated approach of BP neural network and supportability analysis(SA)was proposed to evaluate the criticality of spare parts as well as to prioritize spare parts.Inf... In order to facilitate spare parts management,an integrated approach of BP neural network and supportability analysis(SA)was proposed to evaluate the criticality of spare parts as well as to prioritize spare parts.Influential factors of prioritizing spare parts were detailedly analyzed.Framework of the integrated method was established.The modelling process based on BP neural network was presented.As the input of the neural network,the values of influential factors were determined by supportability analysis data.Based on the presented method,spare parts could be automatically prioritized after supportability analysis for a new system.A case study results showed that the new method was applicable and effective. 展开更多
关键词 spare parts PRIORITIZATION neural network supportability analysis(SA)
下载PDF
A Comparative Study of Support Vector Machine and Artificial Neural Network for Option Price Prediction 被引量:1
13
作者 Biplab Madhu Md. Azizur Rahman +3 位作者 Arnab Mukherjee Md. Zahidul Islam Raju Roy Lasker Ershad Ali 《Journal of Computer and Communications》 2021年第5期78-91,共14页
Option pricing has become one of the quite important parts of the financial market. As the market is always dynamic, it is really difficult to predict the option price accurately. For this reason, various machine lear... Option pricing has become one of the quite important parts of the financial market. As the market is always dynamic, it is really difficult to predict the option price accurately. For this reason, various machine learning techniques have been designed and developed to deal with the problem of predicting the future trend of option price. In this paper, we compare the effectiveness of Support Vector Machine (SVM) and Artificial Neural Network (ANN) models for the prediction of option price. Both models are tested with a benchmark publicly available dataset namely SPY option price-2015 in both testing and training phases. The converted data through Principal Component Analysis (PCA) is used in both models to achieve better prediction accuracy. On the other hand, the entire dataset is partitioned into two groups of training (70%) and test sets (30%) to avoid overfitting problem. The outcomes of the SVM model are compared with those of the ANN model based on the root mean square errors (RMSE). It is demonstrated by the experimental results that the ANN model performs better than the SVM model, and the predicted option prices are in good agreement with the corresponding actual option prices. 展开更多
关键词 Machine Learning support Vector Machine Artificial Neural network PREDICTION Option Price
下载PDF
Exact mesh shape design of large cable-network antenna reflectors with flexible ring truss supports 被引量:4
14
作者 Wang Liu Dong-Xu Li +1 位作者 Xin-Zhan Yu Jian-Ping Jiang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第2期198-205,共8页
An exact-designed mesh shape with favorable surface accuracy is of practical significance to the performance of large cable-network antenna reflectors. In this study, a novel design approach that could guide the gener... An exact-designed mesh shape with favorable surface accuracy is of practical significance to the performance of large cable-network antenna reflectors. In this study, a novel design approach that could guide the generation of exact spatial parabolic mesh configurations of such reflector was proposed. By incorporating the traditional force density method with the standard finite element method, this proposed approach had taken the deformation effects of flexible ring truss supports into consideration, and searched for the desired mesh shapes that can satisfy the requirement that all the free nodes are exactly located on the objective paraboloid. Compared with the conventional design method,a remarkable improvement of surface accuracy in the obtained mesh shapes had been demonstrated by numerical examples. The present work would provide a helpful technical reference for the mesh shape design of such cable-network antenna reflector in engineering practice. 展开更多
关键词 Cable-network Mesh shape design support deformation Force density Surface accuracy
下载PDF
Research and Design of IPv6 Network Management and Operations Support System
15
作者 Chen Bin Ji Wenchong Qiu Zhonghui (China Network Communications Group Corporation, Beijing 100032, China) 《ZTE Communications》 2006年第1期16-20,共5页
IPv6 is the foundation of the development of Next Generation Internet (NGI). An IPv6 network management and operations support system is necessary for real operable NGI. Presently there are no approved standards yet a... IPv6 is the foundation of the development of Next Generation Internet (NGI). An IPv6 network management and operations support system is necessary for real operable NGI. Presently there are no approved standards yet and relevant equipment interfaces are not perfect. A Network Management System (NMS) at the network layer helps implement the integrated management of a network with equipment from multiple vendors, including the network resources and topology, end-to-end network performance, network failures and customer Service Level Agreement (SLA) management. Though the NMS will finally realize pure IPv6 network management, it must be accommodated to the management of relevant IPv4 equipment. Therefore, modularized and layered structure is adopted for the NMS in order to implement its smooth transition. 展开更多
关键词 work Research and Design of IPv6 network Management and Operations support System Design RFC IETF NMS MIB RMON NGI SNMP ICMP
下载PDF
Decision Support System for Maintenance Management Using Bayesian Networks 被引量:1
16
作者 LIU Yan LI Shi-qi 《International Journal of Plant Engineering and Management》 2007年第3期131-138,共8页
The maintenance process has undergone several major developments that have led to proactive considerations and the transformation fiom the traditional "fail and fix" practice into the "predict and prevent" proacti... The maintenance process has undergone several major developments that have led to proactive considerations and the transformation fiom the traditional "fail and fix" practice into the "predict and prevent" proactive maintenance methodology. The anticipation action, which characterizes this proactive maintenance strategy is mainly based on monitoring, diagnosis, prognosis and decision-making modules. Oil monitoring is a key component of a successful condition monitoring program. It can be used as a proactive tool to identify the wear modes of rubbing pans and diagnoses the faults in machinery. But diagnosis relying on oil analysis technology must deal with uncertain knowledge and fuzzy input data. Besides other methods, Bayesian Networks have been extensively applied to fault diagnosis with the advantages of uncertainty inference; however, in the area of oil monitoring, it is a new field. This paper presents an integrated Bayesian network based decision support for maintenance of diesel engines. 展开更多
关键词 decision support system fault diagnosis Bayesian networks oil monitoring
下载PDF
Basic Tenets of Classification Algorithms K-Nearest-Neighbor, Support Vector Machine, Random Forest and Neural Network: A Review 被引量:1
17
作者 Ernest Yeboah Boateng Joseph Otoo Daniel A. Abaye 《Journal of Data Analysis and Information Processing》 2020年第4期341-357,共17页
In this paper, sixty-eight research articles published between 2000 and 2017 as well as textbooks which employed four classification algorithms: K-Nearest-Neighbor (KNN), Support Vector Machines (SVM), Random Forest (... In this paper, sixty-eight research articles published between 2000 and 2017 as well as textbooks which employed four classification algorithms: K-Nearest-Neighbor (KNN), Support Vector Machines (SVM), Random Forest (RF) and Neural Network (NN) as the main statistical tools were reviewed. The aim was to examine and compare these nonparametric classification methods on the following attributes: robustness to training data, sensitivity to changes, data fitting, stability, ability to handle large data sizes, sensitivity to noise, time invested in parameter tuning, and accuracy. The performances, strengths and shortcomings of each of the algorithms were examined, and finally, a conclusion was arrived at on which one has higher performance. It was evident from the literature reviewed that RF is too sensitive to small changes in the training dataset and is occasionally unstable and tends to overfit in the model. KNN is easy to implement and understand but has a major drawback of becoming significantly slow as the size of the data in use grows, while the ideal value of K for the KNN classifier is difficult to set. SVM and RF are insensitive to noise or overtraining, which shows their ability in dealing with unbalanced data. Larger input datasets will lengthen classification times for NN and KNN more than for SVM and RF. Among these nonparametric classification methods, NN has the potential to become a more widely used classification algorithm, but because of their time-consuming parameter tuning procedure, high level of complexity in computational processing, the numerous types of NN architectures to choose from and the high number of algorithms used for training, most researchers recommend SVM and RF as easier and wieldy used methods which repeatedly achieve results with high accuracies and are often faster to implement. 展开更多
关键词 Classification Algorithms NON-PARAMETRIC K-Nearest-Neighbor Neural networks Random Forest support Vector Machines
下载PDF
Novel Method of Predicting Network Bandwidth Based on Support Vector Machines
18
作者 沈伟 冯瑞 邵惠鹤 《Journal of Beijing Institute of Technology》 EI CAS 2004年第4期454-457,共4页
In order to solve the problems of small sample over-fitting and local minima when neural networks learn online, a novel method of predicting network bandwidth based on support vector machines(SVM) is proposed. The pre... In order to solve the problems of small sample over-fitting and local minima when neural networks learn online, a novel method of predicting network bandwidth based on support vector machines(SVM) is proposed. The prediction and learning online will be completed by the proposed moving window learning algorithm(MWLA). The simulation research is done to validate the proposed method, which is compared with the method based on neural networks. 展开更多
关键词 support vector machines(SVM) neural networks network bandwidth bandwidth prediction
下载PDF
基于轴箱垂向振动加速度的地铁车轮失圆状态诊断方法 被引量:2
19
作者 梁红琴 姜进南 +5 位作者 陶功权 刘奇锋 卢纯 温泽峰 张楷 肖乾 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第1期431-443,共13页
首先,建立卷积神经网络、深度置信网络、支持向量机和以一维卷积神经网络全连接层特征为输入的支持向量机模型(1DCNN-SVM),对比上述模型在地铁车轮失圆状态分类识别上的效果;其次,利用代理模型构建轴箱垂向加速度均方根与车速和多边形... 首先,建立卷积神经网络、深度置信网络、支持向量机和以一维卷积神经网络全连接层特征为输入的支持向量机模型(1DCNN-SVM),对比上述模型在地铁车轮失圆状态分类识别上的效果;其次,利用代理模型构建轴箱垂向加速度均方根与车速和多边形磨耗幅值之间的映射关系;最后,通过智能优化算法逆向求解幅值,对比不同代理模型和智能优化算法在多边形磨耗幅值识别上的适用性。研究结果表明:1DCNN-SVM模型在正常、低阶多边形、高阶多边形、随机非圆车轮4类典型的车轮不圆度状态分类识别中取得99.82%的准确性,相比另外3种分类方法,其泛化性能和强化学习能力都具有明显的优势。在车轮多边形磨耗幅值识别方面,基于克里金模型(KSM)和粒子群算法(PSO)的波深识别模型具有更好的预测稳定性和时效性。 展开更多
关键词 车轮多边形磨耗 卷积神经网络 支持向量机 代理模型 智能优化算法
下载PDF
Fuzzy-support vector machine geotechnical risk analysis method based on Bayesian network 被引量:5
20
作者 LIU Yang ZHANG Jian-jing +2 位作者 ZHU Chong-hao XIANG Bo WANG Dong 《Journal of Mountain Science》 SCIE CSCD 2019年第8期1975-1985,共11页
Machine learning method has been widely used in various geotechnical engineering risk analysis in recent years. However, the overfitting problem often occurs due to the small number of samples obtained in history. Thi... Machine learning method has been widely used in various geotechnical engineering risk analysis in recent years. However, the overfitting problem often occurs due to the small number of samples obtained in history. This paper proposes the FuzzySVM(support vector machine) geotechnical engineering risk analysis method based on the Bayesian network. The proposed method utilizes the fuzzy set theory to build a Bayesian network to reflect prior knowledge, and utilizes the SVM to build a Bayesian network to reflect historical samples. Then a Bayesian network for evaluation is built in Bayesian estimation method by combining prior knowledge with historical samples. Taking seismic damage evaluation of slopes as an example, the steps of the method are stated in detail. The proposed method is used to evaluate the seismic damage of 96 slopes along roads in the area affected by the Wenchuan earthquake. The evaluation results show that the method can solve the overfitting problem, which often occurs if the machine learning methods are used to evaluate risk of geotechnical engineering, and the performance of the method is much better than that of the previous machine learning methods. Moreover,the proposed method can also effectively evaluate various geotechnical engineering risks in the absence of some influencing factors. 展开更多
关键词 GEOTECHNICAL evaluation OVERFITTING problem BAYESIAN network Prior knowledge FUZZY set theory support vector machine
下载PDF
上一页 1 2 228 下一页 到第
使用帮助 返回顶部