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A cloud model target damage effectiveness assessment algorithm based on spatio-temporal sequence finite multilayer fragments dispersion
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作者 Hanshan Li Xiaoqian Zhang Junchai Gao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期48-64,共17页
To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage p... To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage probability leveraging spatio-temporal finite multilayer fragments distribution and the target damage assessment algorithm based on cloud model theory.Drawing on the spatial dispersion characteristics of fragments of projectile proximity explosion,we divide into a finite number of fragments distribution planes based on the time series in space,set up a fragment layer dispersion model grounded in the time series and intersection criterion for determining the effective penetration of each layer of fragments into the target.Building on the precondition that the multilayer fragments of the time series effectively assail the target,we also establish the damage criterion of the perforation and penetration damage and deduce the damage probability calculation model.Taking the damage probability of the fragment layer in the spatio-temporal sequence to the target as the input state variable,we introduce cloud model theory to research the target damage assessment method.Combining the equivalent simulation experiment,the scientific and rational nature of the proposed method were validated through quantitative calculations and comparative analysis. 展开更多
关键词 Target damage cloud model Fragments dispersion Effectiveness assessment Spatio-temporal sequence
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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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A Model of Cloud-Based Enterprise Resource Planning (ERP) for Small and Medium Enterprise
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作者 Mohammad Jahangir Alam Shoman Das Sharma Tanjia Chowdhury 《Journal of Computer and Communications》 2024年第10期37-50,共14页
Cloud Computing is an uprising technology in the rapid growing IT world. The adaptation of cloud computing is increasing in very large scale business organizations to small institutions rapidly due to many advanced fe... Cloud Computing is an uprising technology in the rapid growing IT world. The adaptation of cloud computing is increasing in very large scale business organizations to small institutions rapidly due to many advanced features of cloud computing, such as SaaS, PaaS and IaaS service models. So, nowadays, many organizations are trying to implement Cloud Computing based ERP system to enjoy the benefits of cloud computing. To implement any ERP system, an organization usually faces many challenges. As a result, this research has introduced how easily this cloud system can be implemented in an organization. By using this ERP system, an organization can be benefited in many ways;especially Small and Medium Enterprises (SMEs) can enjoy the highest possible benefits from this system. 展开更多
关键词 cloud Computing cloud Comparison cloud models Enterprise Resource planning (ERP) Small and Medium Enterprise (SME)
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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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基于FAHP-CM的舰船电力系统韧性评价研究
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作者 王宇江 狄鹏 +3 位作者 侯丙旭 梁俊鹏 赵耀 陈俊源 《现代防御技术》 北大核心 2024年第5期138-146,共9页
针对当前评价舰船电力系统韧性具有较大的不确定性和主观性问题,在建立舰船电力系统韧性评价指标体系的基础上,将云模型(cloud model,CM)和模糊层次分析法(fuzzy analytic hierarchy process,FAHP)相结合,提出FAHP-CM的舰船电力系统韧... 针对当前评价舰船电力系统韧性具有较大的不确定性和主观性问题,在建立舰船电力系统韧性评价指标体系的基础上,将云模型(cloud model,CM)和模糊层次分析法(fuzzy analytic hierarchy process,FAHP)相结合,提出FAHP-CM的舰船电力系统韧性评价方法。该方法利用FAHP-CM计算评价指标的权重,使权重更加客观准确,同时简化计算过程,提高评估效率。实例分析结果表明,所建立的评价方法能够很好地反映舰船电力系统的韧性,并能有效解决评价的不确定性和主观性问题,使评价结果更加科学合理。 展开更多
关键词 舰船电力系统 韧性评价 云模型 模糊层次分析法 指标体系
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Evaluation of NASA GISS Post-CMIP5 Single Column Model Simulated Clouds and Precipitation Using ARM Southern Great Plains Observations 被引量:3
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作者 Lei ZHANG Xiquan DONG +2 位作者 Aaron KENNEDY Baike XI Zhanqing LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第3期306-320,共15页
The planetary boundary layer turbulence and moist convection parameterizations have been modified recently in the NASA Goddard Institute for Space Studies (GISS) Model E2 atmospheric general circulation model (GCM;... The planetary boundary layer turbulence and moist convection parameterizations have been modified recently in the NASA Goddard Institute for Space Studies (GISS) Model E2 atmospheric general circulation model (GCM; post-CMIP5, hereafter P5). In this study, single column model (SCM_P5) simulated cloud fractions (CFs), cloud liquid water paths (LWPs) and precipitation were compared with Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) groundbased observations made during the period 2002-08. CMIP5 SCM simulations and GCM outputs over the ARM SGP region were also used in the comparison to identify whether the causes of cloud and precipitation biases resulted from either the physical parameterization or the dynamic scheme. The comparison showed that the CMIP5 SCM has difficulties in simulating the vertical structure and seasonal variation of low-level clouds. The new scheme implemented in the turbulence parameterization led to significantly improved cloud simulations in P5. It was found that the SCM is sensitive to the relaxation time scale. When the relaxation time increased from 3 to 24 h, SCM_P5-simulated CFs and LWPs showed a moderate increase (10%-20%) but precipitation increased significantly (56%), which agreed better with observations despite the less accurate atmospheric state. Annual averages among the GCM and SCM simulations were almost the same, but their respective seasonal variations were out of phase. This suggests that the same physical cloud parameterization can generate similar statistical results over a long time period, but different dynamics drive the differences in seasonal variations. This study can potentially provide guidance for the further development of the GISS model. 展开更多
关键词 single column model model evaluation cloud fraction turbulence parameterization
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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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Compensating Errors in Cloud Radiative and Physical Properties over the Southern Ocean in the CMIP6 Climate Models 被引量:1
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作者 Lijun ZHAO Yuan WANG +2 位作者 Chuanfeng ZHAO Xiquan DONG Yuk L.YUNG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第12期2156-2171,共16页
The Southern Ocean is covered by a large amount of clouds with high cloud albedo.However,as reported by previous climate model intercomparison projects,underestimated cloudiness and overestimated absorption of solar r... The Southern Ocean is covered by a large amount of clouds with high cloud albedo.However,as reported by previous climate model intercomparison projects,underestimated cloudiness and overestimated absorption of solar radiation(ASR)over the Southern Ocean lead to substantial biases in climate sensitivity.The present study revisits this long-standing issue and explores the uncertainty sources in the latest CMIP6 models.We employ 10-year satellite observations to evaluate cloud radiative effect(CRE)and cloud physical properties in five CMIP6 models that provide comprehensive output of cloud,radiation,and aerosol.The simulated longwave,shortwave,and net CRE at the top of atmosphere in CMIP6 are comparable with the CERES satellite observations.Total cloud fraction(CF)is also reasonably simulated in CMIP6,but the comparison of liquid cloud fraction(LCF)reveals marked biases in spatial pattern and seasonal variations.The discrepancies between the CMIP6 models and the MODIS satellite observations become even larger in other cloud macroand micro-physical properties,including liquid water path(LWP),cloud optical depth(COD),and cloud effective radius,as well as aerosol optical depth(AOD).However,the large underestimation of both LWP and cloud effective radius(regional means~20%and 11%,respectively)results in relatively smaller bias in COD,and the impacts of the biases in COD and LCF also cancel out with each other,leaving CRE and ASR reasonably predicted in CMIP6.An error estimation framework is employed,and the different signs of the sensitivity errors and biases from CF and LWP corroborate the notions that there are compensating errors in the modeled shortwave CRE.Further correlation analyses of the geospatial patterns reveal that CF is the most relevant factor in determining CRE in observations,while the modeled CRE is too sensitive to LWP and COD.The relationships between cloud effective radius,LWP,and COD are also analyzed to explore the possible uncertainty sources in different models.Our study calls for more rigorous calibration of detailed cloud physical properties for future climate model development and climate projection. 展开更多
关键词 cloud radiative effect cloud physics the Southern Ocean global climate models
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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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基于CWM和CM的长滩露天矿深孔台阶爆破岩体可爆性评价
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作者 史涵虚 周传波 +3 位作者 张升 马义全 蒋楠 田飞 《爆破》 CSCD 北大核心 2024年第1期51-59,119,共10页
在深孔台阶爆破中,对不同地质条件下的岩体按其可爆性进行分级,是进行爆破参数优选优化,确定合理爆破参数的前提,对提高矿区生产爆破效率,改善爆破效果、降低爆破成本具有重要意义。结合长滩露天煤矿爆破开挖实际,通过现场单孔爆破漏斗... 在深孔台阶爆破中,对不同地质条件下的岩体按其可爆性进行分级,是进行爆破参数优选优化,确定合理爆破参数的前提,对提高矿区生产爆破效率,改善爆破效果、降低爆破成本具有重要意义。结合长滩露天煤矿爆破开挖实际,通过现场单孔爆破漏斗试验、岩体声波测试、室内岩石力学试验,获取了岩体体可爆性分级相关指标。基于组合赋权(CWM)和云模型(CM)的可爆性分级方法,对长滩露天煤矿剥离岩体的可爆性进行了分级评价。结果表明长滩露天矿正在剥离爆破的4个平台岩体可爆性为:1130平盘主要分布灰绿色粗砂岩,可爆性为Ⅲ级(中等);1115平盘主要岩性为黄绿色中砂岩,可爆性为Ⅱ级(较难爆);1100平盘是紫红色砂质泥岩,可爆性为Ⅰ级(难爆);1145平盘主要以紫红色泥岩为主,可爆性为Ⅲ级(中等)。 展开更多
关键词 爆破漏斗试验 组合赋权 云模型 可爆性分级
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中国对东盟货物贸易出口波动的影响因素研究——基于改进的CMS模型实证分析
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作者 张兵 曹玉娟 《东南亚纵横》 2024年第2期48-67,共20页
推动外贸稳规模、优结构,对推动高质量发展具有重要支撑作用。为了能够更好地研究贸易结构变化对中国出口的影响,文章对CMS模型进口需求结构效应和出口结构效应及两者细分效应的算法进行了调整,并运用改进的CMS模型对中国出口波动的影... 推动外贸稳规模、优结构,对推动高质量发展具有重要支撑作用。为了能够更好地研究贸易结构变化对中国出口的影响,文章对CMS模型进口需求结构效应和出口结构效应及两者细分效应的算法进行了调整,并运用改进的CMS模型对中国出口波动的影响因素进行实证分析。同时为了研究各影响因素在重要时期对中国出口的影响,文章将研究周期设定为2008—2022年,包括了全球金融危机和新冠疫情等重大事件。研究发现:(1)中国对东盟商品出口规模大幅增长,主要得益于进口需求规模扩大、出口整体竞争力提升,以及两者交互作用的整体交互效应。在结构上表现为进口需求结构效应显著促进出口,出口结构效应抑制出口的特征。(2)出口结构效应抑制出口主要是因为我国出口集中在出口效应较低的国家和商品上。(3)在东盟面临危机时,需求驱动的增长模式和本来就抑制出口的出口结构,对中国出口的负面影响更加明显。因此,为了促进中国对东盟出口平稳增长,需要推动传统产业转型升级和大力发展战略性新兴产业,来提高中国商品出口竞争力;充分利用好RCEP减税和原产地累积等规则挖掘商机;积极推进中国—东盟自由贸易区3.0版谈判,全面提升中国—东盟经贸制度型开放水平,在数字经济和绿色能源经济等领域加强与东盟的合作,培育双边贸易新的增长点。 展开更多
关键词 东盟 货物贸易 出口波动 贸易影响因素 cmS模型
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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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