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Analysis of Secured Cloud Data Storage Model for Information
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作者 Emmanuel Nwabueze Ekwonwune Udo Chukwuebuka Chigozie +1 位作者 Duroha Austin Ekekwe Georgina Chekwube Nwankwo 《Journal of Software Engineering and Applications》 2024年第5期297-320,共24页
This paper was motivated by the existing problems of Cloud Data storage in Imo State University, Nigeria such as outsourced data causing the loss of data and misuse of customer information by unauthorized users or hac... This paper was motivated by the existing problems of Cloud Data storage in Imo State University, Nigeria such as outsourced data causing the loss of data and misuse of customer information by unauthorized users or hackers, thereby making customer/client data visible and unprotected. Also, this led to enormous risk of the clients/customers due to defective equipment, bugs, faulty servers, and specious actions. The aim if this paper therefore is to analyze a secure model using Unicode Transformation Format (UTF) base 64 algorithms for storage of data in cloud securely. The methodology used was Object Orientated Hypermedia Analysis and Design Methodology (OOHADM) was adopted. Python was used to develop the security model;the role-based access control (RBAC) and multi-factor authentication (MFA) to enhance security Algorithm were integrated into the Information System developed with HTML 5, JavaScript, Cascading Style Sheet (CSS) version 3 and PHP7. This paper also discussed some of the following concepts;Development of Computing in Cloud, Characteristics of computing, Cloud deployment Model, Cloud Service Models, etc. The results showed that the proposed enhanced security model for information systems of cooperate platform handled multiple authorization and authentication menace, that only one login page will direct all login requests of the different modules to one Single Sign On Server (SSOS). This will in turn redirect users to their requested resources/module when authenticated, leveraging on the Geo-location integration for physical location validation. The emergence of this newly developed system will solve the shortcomings of the existing systems and reduce time and resources incurred while using the existing system. 展开更多
关键词 cloud DATA Information model Data Storage cloud Computing Security System Data Encryption
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Research on BIM Model Reshaping Method Based on 3D Point Cloud Recognition
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作者 SHI Jin-yu YU Xian-feng +1 位作者 SI Zhan-jun ZHANG Ying-xue 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期125-135,共11页
In view of the limitations of traditional measurement methods in the field of building information,such as complex operation,low timeliness and poor accuracy,a new way of combining three-dimensional scanning technolog... In view of the limitations of traditional measurement methods in the field of building information,such as complex operation,low timeliness and poor accuracy,a new way of combining three-dimensional scanning technology and BIM(Building Information Modeling)model was discussed.Focused on the efficient acquisition of building geometric information using the fast-developing 3D point cloud technology,an improved deep learning-based 3D point cloud recognition method was proposed.The method optimised the network structure based on RandLA-Net to adapt to the large-scale point cloud processing requirements,while the semantic and instance features of the point cloud were integrated to significantly improve the recognition accuracy and provide a precise basis for BIM model remodeling.In addition,a visual BIM model generation system was developed,which systematically transformed the point cloud recognition results into BIM component parameters,automatically constructed BIM models,and promoted the open sharing and secondary development of models.The research results not only effectively promote the automation process of converting 3D point cloud data to refined BIM models,but also provide important technical support for promoting building informatisation and accelerating the construction of smart cities,showing a wide range of application potential and practical value. 展开更多
关键词 3D point cloud RandLA-Net network BIM model OSG engine
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The Cloud Model for Climate Change
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作者 Michael Nelson David B. Nelson 《International Journal of Geosciences》 CAS 2024年第5期366-395,共30页
In 1995, the Intergovernmental Panel on Climate Change (IPCC) released a thermodynamic model based on the Greenhouse Effect, aiming to forecast global temperatures. This study delves into the intricacies of that model... In 1995, the Intergovernmental Panel on Climate Change (IPCC) released a thermodynamic model based on the Greenhouse Effect, aiming to forecast global temperatures. This study delves into the intricacies of that model. Some interesting observations are revealed. The IPCC model equated average temperatures with average energy fluxes, which can cause significant errors. The model assumed that all energy fluxes remained constant, and the Earth emitted infrared radiation as if it were a blackbody. Neither of those conditions exists. The IPCC’s definition of Climate Change only includes events caused by human actions, excluding most causes. Satellite data aimed at the tops of clouds may have inferred a high Greenhouse Gas absorption flux. The model showed more energy coming from the atmosphere than absorbed from the sun, which may have caused a violation of the First and Second Laws of Thermodynamics. There were unexpectedly large gaps in the satellite data that aligned with various absorption bands of Greenhouse Gases, possibly caused by photon scattering associated with re-emissions. Based on science, we developed a cloud-based climate model that complied with the Radiation Laws and the First and Second Laws of Thermodynamics. The Cloud Model showed that 81.3% of the outgoing reflected and infrared radiation was applicable to the clouds and water vapor. In comparison, the involvement of CO<sub>2</sub> was only 0.04%, making it too minuscule to measure reliably. 展开更多
关键词 Climate Change Greenhouse Gas CO2 cloudS model THERMODYNAMICS
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Risk assessment of high-speed railway CTC system based on improved game theory and cloud model
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作者 Yanhao Sun Tao Zhang +2 位作者 Shuxin Ding Zhiming Yuan Shengliang Yang 《Railway Sciences》 2024年第3期388-410,共23页
Purpose-In order to solve the problem of inaccurate calculation of index weights,subjectivity and uncertainty of index assessment in the risk assessment process,this study aims to propose a scientific and reasonable c... Purpose-In order to solve the problem of inaccurate calculation of index weights,subjectivity and uncertainty of index assessment in the risk assessment process,this study aims to propose a scientific and reasonable centralized traffic control(CTC)system risk assessment method.Design/methodologylapproach-First,system-theoretic process analysis(STPA)is used to conduct risk analysis on the CTC system and constructs risk assessment indexes based on this analysis.Then,to enhance the accuracy of weight calculation,the fuzzy analytical hierarchy process(FAHP),fuzzy decision-making trial and evaluation laboratory(FDEMATEL)and entropy weight method are employed to calculate the subjective weight,relative weight and objective weight of each index.These three types of weights are combined using game theory to obtain the combined weight for each index.To reduce subjectivity and uncertainty in the assessment process,the backward cloud generator method is utilized to obtain the numerical character(NC)of the cloud model for each index.The NCs of the indexes are then weighted to derive the comprehensive cloud for risk assessment of the CTC system.This cloud model is used to obtain the CTC system's comprehensive risk assessment.The model's similarity measurement method gauges the likeness between the comprehensive risk assessment cloud and the risk standard cloud.Finally,this process yields the risk assessment results for the CTC system.Findings-The cloud model can handle the subjectivity and fuzziness in the risk assessment process well.The cloud model-based risk assessment method was applied to the CTC system risk assessment of a railway group and achieved good results.Originality/value-This study provides a cloud model-based method for risk assessment of CTC systems,which accurately calculates the weight of risk indexes and uses cloud models to reduce uncertainty and subjectivity in the assessment,achieving effective risk assessment of CTC systems.It can provide a reference and theoretical basis for risk management of the CTC system. 展开更多
关键词 High-speed railway Centralized traffic control Risk assessment Game theory cloud model Paper type Research paper
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Evaluation of toppling rock slopes using a composite cloud model with DEMATEL–CRITIC method 被引量:3
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作者 Huan-ling Wang Xu-fei Zhao +3 位作者 Hong-jie Chen Kui Yi Wei-chau Xie Wei-ya Xu 《Water Science and Engineering》 EI CAS CSCD 2023年第3期280-288,共9页
Safety evaluation of toppling rock slopes developing in reservoir areas is crucial. To reduce the uncertainty of safety evaluation, this study developed a composite cloud model, which improved the combination weights ... Safety evaluation of toppling rock slopes developing in reservoir areas is crucial. To reduce the uncertainty of safety evaluation, this study developed a composite cloud model, which improved the combination weights of the decision-making trial and evaluation laboratory (DEMATEL) and criteria importance through intercriteria correlation (CRITIC) methods. A safety evaluation system was developed according to in situ monitoring data. The backward cloud generator was used to calculate the numerical characteristics of a cloud model of quantitative indices, and different virtual clouds were used to synthesize some clouds into a generalized one. The synthesized numerical characteristics were calculated to comprehensively evaluate the safety of toppling rock slopes. A case study of a toppling rock slope near the Huangdeng Hydropower Station in China was conducted using monitoring data collected since operation of the hydropower project began. The results indicated that the toppling rock slope was moderately safe with a low safety margin. The composite cloud model considers the fuzziness and randomness of safety evaluation and enables interchange between qualitative and quantitative knowledge. This study provides a new theoretical method for evaluating the safety of toppling rock slopes. It can aid in the predication, control, and even prevention of disasters. 展开更多
关键词 Toppling rock slope Safety evaluation Composite cloud model DEMATEL CRITIC Huangdeng Hydropower Project
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A novel mathematical model on Peer-to-Peer botnet
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作者 任玮 宋礼鹏 冯丽萍 《Journal of Measurement Science and Instrumentation》 CAS 2014年第4期62-67,共6页
Peer-to-Peer (P2P) botnet has emerged as one of the most serious threats to lnternet security. To effectively elimi- nate P2P botnet, a delayed SEIR model is proposed,which can portray the formation process of P2P b... Peer-to-Peer (P2P) botnet has emerged as one of the most serious threats to lnternet security. To effectively elimi- nate P2P botnet, a delayed SEIR model is proposed,which can portray the formation process of P2P botnet. Then, the local stability at equilibria is carefully analyzed by considering the eigenvalues' distributed ranges of characteristic equations. Both mathematical analysis and numerical simulations show that the dynamical features of the proposed model rely on the basic re- production number and time delay r. The results can help us to better understand the propagation behaviors of P2P botnet and design effective counter-botnet methods. 展开更多
关键词 peer-to-peer (P2P) botnet STABILITY SEIR model time delay
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Safety Risk Assessment of Overturning Construction of Towering Structure Based on Cloud Matter–Element Coupled Model
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作者 Yingxue Sang Fengxia Han +2 位作者 Qing Liu Liang Qiao Shouxi Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期1973-1998,共26页
Rapid urbanization has led to a surge in the number of towering structures,and overturning is widely used because it can better accommodate the construction of shaped structures such as variable sections.The complexit... Rapid urbanization has led to a surge in the number of towering structures,and overturning is widely used because it can better accommodate the construction of shaped structures such as variable sections.The complexity of the construction process makes the construction risk have certain randomness,so this paper proposes a cloudbased coupled matter-element model to address the ambiguity and randomness in the safety risk assessment of overturning construction of towering structures.In the pretended model,the digital eigenvalues of the cloud model are used to replace the eigenvalues in the matter–element basic element,and calculate the cloud correlation of the risk assessment metrics through the correlation algorithm of the cloud model to build the computational model.Meanwhile,the improved hierarchical analysis method based on the cloud model is used to determine the weight of the index.The comprehensive evaluation scores of the evaluation event are then obtained through the weighted average method,and the safety risk level is determined accordingly.Through empirical analysis,(1)the improved hierarchical analysis method based on the cloud model can incorporate the data of multiple decisionmakers into the calculation formula to determine theweights,which makes the assessment resultsmore credible;(2)the evaluation results of the cloud-basedmatter-element coupledmodelmethod are basically consistent with those of the other two commonly used methods,and the confidence factor is less than 0.05,indicating that the cloudbased physical element coupled model method is reasonable and practical for towering structure overturning;(3)the cloud-based coupled element model method,which confirms the reliability of risk level by performing Spearman correlation on comprehensive assessment scores,can provide more comprehensive information of instances compared with other methods,and more comprehensively reflects the fuzzy uncertainty relationship between assessment indexes,which makes the assessment results more realistic,scientific and reliable. 展开更多
关键词 cloud matter-element model clouded hierarchical analysis method towering structure overturning formwork construction risk assessment
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Formal Modeling of Self-Adaptive Resource Scheduling in Cloud
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作者 Atif Ishaq Khan Syed Asad Raza Kazmi Awais Qasim 《Computers, Materials & Continua》 SCIE EI 2023年第1期1183-1197,共15页
A self-adaptive resource provisioning on demand is a critical factor in cloud computing.The selection of accurate amount of resources at run time is not easy due to dynamic nature of requests.Therefore,a self-adaptive... A self-adaptive resource provisioning on demand is a critical factor in cloud computing.The selection of accurate amount of resources at run time is not easy due to dynamic nature of requests.Therefore,a self-adaptive strategy of resources is required to deal with dynamic nature of requests based on run time change in workload.In this paper we proposed a Cloud-based Adaptive Resource Scheduling Strategy(CARSS)Framework that formally addresses these issues and is more expressive than traditional approaches.The decision making in CARSS is based on more than one factors.TheMAPE-K based framework determines the state of the resources based on their current utilization.Timed-Arc Petri Net(TAPN)is used to model system formally and behaviour is expressed in TCTL,while TAPAAL model checker verifies the underline properties of the system. 展开更多
关键词 Formal modeling MULTI-AGENT SELF-ADAPTIVE cloud computing
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Vulnerability assessment of coastal wetlands in Minjiang River Estuary based on cloud model under sea level rise
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作者 Xiaohe Lai Chuqing Zeng +4 位作者 Yan Su Shaoxiang Huang Jianping Jia Cheng Chen Jun Jiang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第7期160-174,共15页
The change of coastal wetland vulnerability affects the ecological environment and the economic development of the estuary area.In the past,most of the assessment studies on the vulnerability of coastal ecosystems sta... The change of coastal wetland vulnerability affects the ecological environment and the economic development of the estuary area.In the past,most of the assessment studies on the vulnerability of coastal ecosystems stayed in static qualitative research,lacking predictability,and the qualitative and quantitative relationship was not objective enough.In this study,the“Source-Pathway-Receptor-Consequence”model and the Intergovernmental Panel on Climate Change vulnerability definition were used to analyze the main impact of sea level rise caused by climate change on coastal wetland ecosystem in Minjiang River Estuary.The results show that:(1)With the increase of time and carbon emission,the area of high vulnerability and the higher vulnerability increased continuously,and the area of low vulnerability and the lower vulnerability decreased.(2)The eastern and northeastern part of the Culu Island in the Minjiang River Estuary of Fujian Province and the eastern coastal wetland of Meihua Town in Changle District are areas with high vulnerability risk.The area of high vulnerability area of coastal wetland under high emission scenario is wider than that under low emission scenario.(3)Under different sea level rise scenarios,elevation has the greatest impact on the vulnerability of coastal wetlands,and slope has less impact.The impact of sea level rise caused by climate change on the coastal wetland ecosystem in the Minjiang River Estuary is mainly manifested in the sea level rise,which changes the habitat elevation and daily flooding time of coastal wetlands,and then affects the survival and distribution of coastal wetland ecosystems. 展开更多
关键词 vulnerability assessment cloud model coastal wetland Minjiang River Estuary
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Building 3D CityGML models of mining industrial structures using integrated UAV and TLS point clouds
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作者 Canh Le Van Cuong Xuan Cao +2 位作者 Anh Ngoc Nguyen Chung Van Pham Long Quoc Nguyen 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第5期158-177,共20页
Mining industrial areas with anthropogenic engineering structures are one of the most distinctive features of the real world.3D models of the real world have been increasingly popular with numerous applications,such a... Mining industrial areas with anthropogenic engineering structures are one of the most distinctive features of the real world.3D models of the real world have been increasingly popular with numerous applications,such as digital twins and smart factory management.In this study,3D models of mining engineering structures were built based on the CityGML standard.For collecting spatial data,the two most popular geospatial technologies,namely UAV-SfM and TLS were employed.The accuracy of the UAV survey was at the centimeter level,and it satisfied the absolute positional accuracy requirement of creat-ing all levels of detail(LoD)according to the CityGML standard.Therefore,the UAV-SfM point cloud dataset was used to build LoD 2 models.In addition,the comparison between the UAV-SfM and TLS sub-clouds of facades and roofs indicates that the UAV-SfM and TLS point clouds of these objects are highly consistent,therefore,point clouds with a higher level of detail and accuracy provided by the integration of UAV-SfM and TLS were used to build LoD 3 models.The resulting 3D CityGML models include 39 buildings at LoD 2,and two mine shafts with hoistrooms,headframes,and sheave wheels at LoD3. 展开更多
关键词 3D modelling CityGML-Mining industry UAV Terrestrial laser scanning Point cloud
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Container Based Nomadic Vehicular Cloud Using Cell Transmission Model
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作者 Devakirubai Navulkumar Menakadevi Thangavelu 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期423-440,共18页
Nomadic Vehicular Cloud(NVC)is envisaged in this work.The predo-minant aspects of NVC is,it moves along with the vehicle that initiates it and functions only with the resources of moving vehicles on the heavy traffic ... Nomadic Vehicular Cloud(NVC)is envisaged in this work.The predo-minant aspects of NVC is,it moves along with the vehicle that initiates it and functions only with the resources of moving vehicles on the heavy traffic road without relying on any of the static infrastructure and NVC decides the initiation time of container migration using cell transmission model(CTM).Containers are used in the place of Virtual Machines(VM),as containers’features are very apt to NVC’s dynamic environment.The specifications of 5G NR V2X PC5 interface are applied to NVC,for the feature of not relying on the network coverage.Nowa-days,the peak traffic on the road and the bottlenecks due to it are inevitable,which are seen here as the benefits for VC in terms of resource availability and residual in-network time.The speed range of high-end vehicles poses the issue of dis-connectivity among VC participants,that results the container migration failure.As the entire VC participants are on the move,to maintain proximity of the containers hosted by them,estimating their movements plays a vital role.To infer the vehicle movements on the road stretch and initiate the container migration prior enough to avoid the migration failure due to vehicles dynamicity,this paper proposes to apply the CTM to the container based and 5G NR V2X enabled NVC.The simulation results show that there is a significant increase in the success rate of vehicular cloud in terms of successful container migrations. 展开更多
关键词 Vehicular cloud container migration cell transmission model 5G NR V2X PC5 interface
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Modularized and Parametric Modeling Technology for Finite Element Simulations of Underground Engineering under Complicated Geological Conditions
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作者 Jiaqi Wu Li Zhuo +4 位作者 Jianliang Pei Yao Li Hongqiang Xie Jiaming Wu Huaizhong Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期621-645,共25页
The surrounding geological conditions and supporting structures of underground engineering are often updated during construction,and these updates require repeated numerical modeling.To improve the numerical modeling ... The surrounding geological conditions and supporting structures of underground engineering are often updated during construction,and these updates require repeated numerical modeling.To improve the numerical modeling efficiency of underground engineering,a modularized and parametric modeling cloud server is developed by using Python codes.The basic framework of the cloud server is as follows:input the modeling parameters into the web platform,implement Rhino software and FLAC3D software to model and run simulations in the cloud server,and return the simulation results to the web platform.The modeling program can automatically generate instructions that can run the modeling process in Rhino based on the input modeling parameters.The main modules of the modeling program include modeling the 3D geological structures,the underground engineering structures,and the supporting structures as well as meshing the geometric models.In particular,various cross-sections of underground caverns are crafted as parametricmodules in themodeling program.Themodularized and parametric modeling program is used for a finite element simulation of the underground powerhouse of the Shuangjiangkou Hydropower Station.This complicatedmodel is rapidly generated for the simulation,and the simulation results are reasonable.Thus,this modularized and parametric modeling program is applicable for three-dimensional finite element simulations and analyses. 展开更多
关键词 Underground engineering modularized and parametric modeling finite element method complex geological structure cloud modeling
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Cloudless-Training:基于serverless的高效跨地域分布式ML训练框架
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作者 谭文婷 吕存驰 +1 位作者 史骁 赵晓芳 《高技术通讯》 CAS 北大核心 2024年第3期219-232,共14页
跨地域分布式机器学习(ML)训练能够联合多区域的云资源协作训练,可满足许多新兴ML场景(比如大型模型训练、联邦学习)的训练需求。但其训练效率仍受2方面挑战的制约。首先,多区域云资源缺乏有效的弹性调度,这会影响训练的资源利用率和性... 跨地域分布式机器学习(ML)训练能够联合多区域的云资源协作训练,可满足许多新兴ML场景(比如大型模型训练、联邦学习)的训练需求。但其训练效率仍受2方面挑战的制约。首先,多区域云资源缺乏有效的弹性调度,这会影响训练的资源利用率和性能;其次,模型跨地域同步需要在广域网(WAN)上高频通信,受WAN的低带宽和高波动的影响,会产生巨大通信开销。本文提出Cloudless-Training,从3个方面实现高效的跨地域分布式ML训练。首先,它基于serverless计算模式实现,使用控制层和训练执行层的2层架构,支持多云区域的弹性调度和通信。其次,它提供一种弹性调度策略,根据可用云资源的异构性和训练数据集的分布自适应地部署训练工作流。最后,它提供了2种高效的跨云同步策略,包括基于梯度累积的异步随机梯度下降(ASGD-GA)和跨云参数服务器(PS)间的模型平均(MA)。Cloudless-Training是基于OpenFaaS实现的,并被部署在腾讯云上评估,实验结果表明Cloudless-Training可显著地提高跨地域分布式ML训练的资源利用率(训练成本降低了9.2%~24.0%)和同步效率(训练速度最多比基线快1.7倍),并能保证模型的收敛精度。 展开更多
关键词 跨地域分布式机器学习(ML)训练 跨云ML训练 分布式训练框架 serverless 跨云模型同步
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Exploring Multi-Task Learning for Forecasting Energy-Cost Resource Allocation in IoT-Cloud Systems
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作者 Mohammad Aldossary Hatem A.Alharbi Nasir Ayub 《Computers, Materials & Continua》 SCIE EI 2024年第6期4603-4620,共18页
Cloud computing has become increasingly popular due to its capacity to perform computations without relying on physical infrastructure,thereby revolutionizing computer processes.However,the rising energy consumption i... Cloud computing has become increasingly popular due to its capacity to perform computations without relying on physical infrastructure,thereby revolutionizing computer processes.However,the rising energy consumption in cloud centers poses a significant challenge,especially with the escalating energy costs.This paper tackles this issue by introducing efficient solutions for data placement and node management,with a clear emphasis on the crucial role of the Internet of Things(IoT)throughout the research process.The IoT assumes a pivotal role in this study by actively collecting real-time data from various sensors strategically positioned in and around data centers.These sensors continuously monitor vital parameters such as energy usage and temperature,thereby providing a comprehensive dataset for analysis.The data generated by the IoT is seamlessly integrated into the Hybrid TCN-GRU-NBeat(NGT)model,enabling a dynamic and accurate representation of the current state of the data center environment.Through the incorporation of the Seagull Optimization Algorithm(SOA),the NGT model optimizes storage migration strategies based on the latest information provided by IoT sensors.The model is trained using 80%of the available dataset and subsequently tested on the remaining 20%.The results demonstrate the effectiveness of the proposed approach,with a Mean Squared Error(MSE)of 5.33%and a Mean Absolute Error(MAE)of 2.83%,accurately estimating power prices and leading to an average reduction of 23.88%in power costs.Furthermore,the integration of IoT data significantly enhances the accuracy of the NGT model,outperforming benchmark algorithms such as DenseNet,Support Vector Machine(SVM),Decision Trees,and AlexNet.The NGT model achieves an impressive accuracy rate of 97.9%,surpassing the rates of 87%,83%,80%,and 79%,respectively,for the benchmark algorithms.These findings underscore the effectiveness of the proposed method in optimizing energy efficiency and enhancing the predictive capabilities of cloud computing systems.The IoT plays a critical role in driving these advancements by providing real-time data insights into the operational aspects of data centers. 展开更多
关键词 cloud computing energy efficiency data center optimization internet of things(IoT) hybrid models
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Indoor Space Modeling and Parametric Component Construction Based on 3D Laser Point Cloud Data
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作者 Ruzhe Wang Xin Li Xin Meng 《Journal of World Architecture》 2023年第5期37-45,共9页
In order to enhance modeling efficiency and accuracy,we utilized 3D laser point cloud data for indoor space modeling.Point cloud data was obtained with a 3D laser scanner and optimized with Autodesk Recap and Revit so... In order to enhance modeling efficiency and accuracy,we utilized 3D laser point cloud data for indoor space modeling.Point cloud data was obtained with a 3D laser scanner and optimized with Autodesk Recap and Revit software to extract geometric information about the indoor environment.Furthermore,we proposed a method for constructing indoor elements based on parametric components.The research outcomes of this paper will offer new methods and tools for indoor space modeling and design.The approach of indoor space modeling based on 3D laser point cloud data and parametric component construction can enhance modeling efficiency and accuracy,providing architects,interior designers,and decorators with a better working platform and design reference. 展开更多
关键词 3D laser scanning technology Indoor space point cloud data Building information modeling(BIM)
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基于CloudSim的电力系统计算云原生模型与仿真方法
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作者 陈元榉 刘媛媛 +3 位作者 张延旭 蔡煜 胡春潮 蔡泽祥 《电力自动化设备》 EI CSCD 北大核心 2024年第9期189-196,204,共9页
分析基于云计算的电力系统计算过程是实现资源高效利用的基础。因此,提出一种基于CloudSim的电力系统计算的云原生建模与仿真方法。基于云原生技术阐述了电力系统计算架构的关键要素,提出基于CloudSim的电力系统计算架构的云原生模型,... 分析基于云计算的电力系统计算过程是实现资源高效利用的基础。因此,提出一种基于CloudSim的电力系统计算的云原生建模与仿真方法。基于云原生技术阐述了电力系统计算架构的关键要素,提出基于CloudSim的电力系统计算架构的云原生模型,分析电力云任务调配时的资源供需平衡问题。建立基于微服务的电力云任务模型,分析微服务的处理时序逻辑及其层级关系并生成微服务队列。据此提出微服务的动态调配模型,采用微服务-容器映射策略与实体动态整合策略,实现微服务在实体间的动态映射。利用CloudSim进行仿真分析,结果证明所提方法可行且有效,可为电力云计算的资源配置、任务调度等提供基本的仿真工具与方法。 展开更多
关键词 电力系统 cloudSim 云原生建模 电力系统计算架构 动态调配 时序逻辑 微服务队列
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Cloud Service Provisioning Based on Peer-to-Peer Network for Flexible Service Sharing and Discovery
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作者 Andrii Zhygmanovskyi Norihiko Yoshida 《Journal of Computer and Communications》 2014年第10期17-31,共15页
In this paper, we present an approach to establish efficient and scalable service provisioning in the cloud environment using P2P-based infrastructure for storing, sharing and discovering services. Unlike most other P... In this paper, we present an approach to establish efficient and scalable service provisioning in the cloud environment using P2P-based infrastructure for storing, sharing and discovering services. Unlike most other P2P-based approaches, it allows flexible search queries, since all of them are executed against internal database presenting at each overlay node. Various issues concerning using this approach in the cloud environment, such as load-balancing, queuing, dealing with skewed data and dynamic attributes, are addressed in the paper. The infrastructure proposed in the paper can serve as a base for creating robust, scalable and reliable cloud systems, able to fulfill client’s QoS requirements, and at the same time introduce more efficient utilization of resources to the cloud provider. 展开更多
关键词 peer-to-peer cloud Computing SERVICE PROVISIONING SERVICE DISCOVERY SERVICE SHARING
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Prediction of rock burst classification using cloud model with entropy weight 被引量:28
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作者 周科平 林允 +2 位作者 邓红卫 李杰林 刘传举 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1995-2002,共8页
The method of cloud model with entropy weight was adopted for the prediction of rock burst classification. Some main factors of rock burst including the uniaxial compressive strength (σc), the tensile strength (σ... The method of cloud model with entropy weight was adopted for the prediction of rock burst classification. Some main factors of rock burst including the uniaxial compressive strength (σc), the tensile strength (σt), the tangential stress (σθ), the rock brittleness coefficient (σc/σt), the stress coefficient (σθ /σc) and the elastic energy index (Wet) are chosen to establish evaluation index system. The entropy?cloud model and criterion are obtained through 209 sets of rock burst samples from underground rock projects. The sensitivity of indicators is analyzed and 209 sets of rock burst samples are discriminated by this model. The discriminant results of the entropy-cloud model are compared with those of Bayes, KNN and RF methods. The results show that the sensitivity order of those factors from high to low is σ_θ /σ_c, σ_θ, W_(ct), σ_c/σ_t, σ_t, σ_c, and the entropy-cloud model has higher accuracy than Bayes, K-Nearest Neighbor algorithm (KNN) and Random Forest (RF) methods. 展开更多
关键词 rock burst PREDICTION cloud model entropy weight sensitivity
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Expressway traffic flow prediction using chaos cloud particle swarm algorithm and PPPR model 被引量:2
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作者 赵泽辉 康海贵 李明伟 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期328-335,共8页
Aiming at the real-time fluctuation and nonlinear characteristics of the expressway short-term traffic flow forecasting the parameter projection pursuit regression PPPR model is applied to forecast the expressway traf... Aiming at the real-time fluctuation and nonlinear characteristics of the expressway short-term traffic flow forecasting the parameter projection pursuit regression PPPR model is applied to forecast the expressway traffic flow where the orthogonal Hermite polynomial is used to fit the ridge functions and the least square method is employed to determine the polynomial weight coefficient c.In order to efficiently optimize the projection direction a and the number M of ridge functions of the PPPR model the chaos cloud particle swarm optimization CCPSO algorithm is applied to optimize the parameters. The CCPSO-PPPR hybrid optimization model for expressway short-term traffic flow forecasting is established in which the CCPSO algorithm is used to optimize the optimal projection direction a in the inner layer while the number M of ridge functions is optimized in the outer layer.Traffic volume weather factors and travel date of the previous several time intervals of the road section are taken as the input influencing factors. Example forecasting and model comparison results indicate that the proposed model can obtain a better forecasting effect and its absolute error is controlled within [-6,6] which can meet the application requirements of expressway traffic flow forecasting. 展开更多
关键词 expressway traffic flow forecasting projectionpursuit regression particle swarm algorithm chaoticmapping cloud model
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MODEL RECONSTRUCTION FROM CLOUD DATA FOR RAPID PROTOTYPE MANUFACTURING 被引量:1
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作者 张丽艳 周儒荣 周来水 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第2期170-175,共6页
Model reconstruction from points scanned on existing physical objects is much important in a variety of situations such as reverse engineering for mechanical products, computer vision and recovery of biological shapes... Model reconstruction from points scanned on existing physical objects is much important in a variety of situations such as reverse engineering for mechanical products, computer vision and recovery of biological shapes from two dimensional contours. With the development of measuring equipment, cloud points that contain more details of the object can be obtained conveniently. On the other hand, large quantity of sampled points brings difficulties to model reconstruction method. This paper first presents an algorithm to automatically reduce the number of cloud points under given tolerance. Triangle mesh surface from the simplified data set is reconstructed by the marching cubes algorithm. For various reasons, reconstructed mesh usually contains unwanted holes. An approach to create new triangles is proposed with optimized shape for covering the unexpected holes in triangle meshes. After hole filling, watertight triangle mesh can be directly output in STL format, which is widely used in rapid prototype manufacturing. Practical examples are included to demonstrate the method. 展开更多
关键词 reverse engineering model reconstruction cloud data data filtering hole filling
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