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URMG: Enhanced CBMG-Based Method for Automatically Testing Web Applications in the cloud

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Tsinghua Science and Technology 2014年第1期19卷 65-75页

作者： Xiaolin Xu Hai Jin Song Wu Lixiang Tang Yihong Wang Services Computing Technology and System Lab and Cluster and Grid Computing Lab School of Computer Science and Technology Huazhong University of Science and Technology

To satisfy the rapid growth of cloud technologies, a large number of web applications have been developed and deployed, and these applications are being run in clouds. Due to the scalability provided by clouds, a single web application may be concurrently visited by several millions or billions of users. Thus, the testing and performance evaluations of these applications are increasingly important. User model based evaluations can significantly reduce the manual work required, and can enable us to determine the performance of applications under real runtime environments. Hence, it has become one of the most popular evaluation methods in both industry and academia. Significant efforts have focused on building different kinds of models using mining web access logs, such as Markov models and Customer Behavior Model Graph （CBMG）. This paper proposes a new kind of model, named the User Representation Model Graph （URMG）, which is built based on CBMG. It uses an algorithm to refine CBMG and optimizes the evaluations execution process. Based on this model, an automatic testing and evaluation system for web applications is designed, implemented, and deployed in our test cloud, which is able to execute all of the analysis and testing operations using only web access logs. In our system, the error rate caused by random access to applications in the execution phase is also reduced, and the results show that the error rate of the evaluation that depends on URMG is 50% less than that which depends on CBMG.

关键词： cloud web application performance evaluation customer behavior user representation

A Comparison of cloud Layers from Ground and Satellite Active Remote Sensing at the Southern Great Plains ARM Site

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Advances in Atmospheric Sciences 2017年第3期34卷 347-359页

作者： Jinqiang ZHANG Xiang'ao XIA Hongbin CHEN Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Center of Technical Support and Service Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China

Using the data collected over the Southern Great Plains ARM site from 2006 to 2010, the surface Active Remote Sensing of cloud （ARSCL） and cloudSat-CALIPSO satellite （CC） retrievals of total cloud and six specified cloud types [low, midlow （ML）, high-mid-low （HML）, mid, high-mid （HM） and high] were compared in terms of cloud fraction （CF）, cloud-base height （CBH）, cloud-top height （CTH） and cloud thickness （CT）, on different temporal scales, to identify their respective advantages and limitations. Good agreement between the two methods was exhibited in the total CF. However, large discrepancies were found between the cloud distributions of the two methods at a high （240-m） vertical grid spacing. Compared to the satellites, ARSCL retrievals detected more boundary layer clouds, while they underestimated high clouds. In terms of the six specific cloud types, more low- and mid-level clouds but less HML- and high-level clouds were detected by ARSCL than by CC. In contrast, the ARSCL retrievals of ML- and HM-level clouds agreed more closely with the estimations from the CC product. Lower CBHs tended to be reported by the surface data for low-, ML- and HML-level clouds; however, higher CTHs were often recorded by the satellite product for HML-, HM- and high-level clouds. The mean CTs for low- and ML-level cloud were similar between the two products; however, the mean CTs for HML-, mid-, HM- and high-level clouds from ARSCL were smaller than those from CC.

关键词： surface satellite active remote sensing cloud

Smart Meter Development for cloud-Based Home Electricity Monitor System

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Journal of Electronic Science and Technology 2020年第4期18卷 378-390页

作者： Yeong-Chin Chen Sunneng Sandino Berutu Yue-Hsien Wang Department of Computer Science and Information Engineering Asia UniversityTaichung 41354 Department of Computer Science and Engineening Chung Hsing UnversityTaichung 32001

Αcloud-based home electricity data-monitoring system,which is based on an Arduino Mega controller,is proposed for monitoring the electricity consumption(electrical power)and power quality(PQ)in home.This system is also capable of monitoring the fundamental frequency and supply-voltage transients to ensure that the appliances operate in a safe operation range.The measured data(voltage and current)are transmitted through a Wi Fi device between the Arduino controller and server.The transmission control protocol(TCP)server is set up to acquire the high-data transmission rate.The server system immediately displays the calculated parameters and the waveform of the acquired signal.A comparison with a standard measurement device shows that the proposed system,which can be built at a low cost,exhibits the same functions as a factory product.

关键词： Arduino controller cloud electrical power power monitoring transmission control protocol(TCP)ser

Public "cloud" Provisioning for Venus Express VMC Image Processing

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Communications on Applied Mathematics and Computation 2019年第2期1卷 253-261页

作者： J.L.Vazquez-Poletti M.P.Velasco S.Jimenez D.Usero I.M.Llorente L.Vazquez O.Korablev D.Belyaev M.V.Patsaeva I.V.Khatuntsev Instituto de Matematica Interdisdiciplinar (IMI) Universidad Complutense de Madrid28040 MadridSpain Universidad Politdcnica de Madrid 28040 MadridSpain Space Research Institute of Russian Academy of Sciences (IKI) 117997 MoscowRussia

In this paper,we consider the implementation of the “cloud" computing strategy to study data sets associated to the atmospheric exploration of the planet Venus. More concretely,the Venus Monitoring Camera (VMC) onboard Venus Express orbiter provided the largest and the longest so far set of ultraviolet (UV),visible and near-IR images for investigation of the atmospheric circulation. To our best knowledge,this is the first time where the analysis of data from missions to Venus is integrated in the context of the "cloud" computing. The followed path and protocols can be extended to more general cases of space data analysis,and to the general framework of the big data analysis.

关键词： Retrieval Data integration cloud computing Big data

LASG Global AGCM with a Two-moment cloud Microphysics Scheme:Energy Balance and cloud Radiative Forcing Characteristics

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Advances in Atmospheric Sciences 2019年第7期36卷 697-710页

作者： Lei WANG Qing BAO Wei-Chyung WANG Yimin LIU Guo-Xiong WU Linjiong ZHOU JiANDong LI Hua GONG Guokui NIAN Jinxiao LI Xiaocong WANG Bian HE State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing100029China CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing100101China College of Earth and Planetary Sciences University of the Chinese Academy of SciencesBeijing100049China Atmospheric Sciences Research Center State University of New YorkAlbanyNew York12203USA National Oceanic and Atmospheric Administration Geophysical Fluid Dynamics LaboratoryPrincetonNJ08540-6649USA

cloud dominates influence factors of atmospheric radiation, while aerosol–cloud interactions are of vital importance in its spatiotemporal distribution. In this study, a two-moment(mass and number) cloud microphysics scheme, which significantly improved the treatment of the coupled processes of aerosols and clouds, was incorporated into version 1.1 of the IAP/LASG global Finite-volume Atmospheric Model(FAMIL1.1). For illustrative purposes, the characteristics of the energy balance and cloud radiative forcing(CRF) in an AMIP-type simulation with prescribed aerosols were compared with those in observational/reanalysis data. Even within the constraints of the prescribed aerosol mass, the model simulated global mean energy balance at the top of the atmosphere(TOA) and at the Earth’s surface, as well as their seasonal variation, are in good agreement with the observational data. The maximum deviation terms lie in the surface downwelling longwave radiation and surface latent heat flux, which are 3.5 W m-2(1%) and 3 W m-2(3.5%), individually. The spatial correlations of the annual TOA net radiation flux and the net CRF between simulation and observation were around 0.97 and 0.90, respectively. A major weakness is that FAMIL1.1 predicts more liquid water content and less ice water content over most oceans. Detailed comparisons are presented for a number of regions, with a focus on the Asian monsoon region(AMR). The results indicate that FAMIL1.1 well reproduces the summer–winter contrast for both the geographical distribution of the longwave CRF and shortwave CRF over the AMR. Finally, the model bias and possible solutions, as well as further works to develop FAMIL1.1 are discussed.

关键词： two-moment cloud microphysics scheme aerosol–cloud interactions energy balance cloud radiative forcing Asian monsoon region

Impact of the Assimilation Frequency of Radar Data with the ARPS 3DVar and cloud Analysis System on Forecasts of a Squall Line in Southern China

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Advances in Atmospheric Sciences 2019年第2期36卷 160-172页

作者： Yujie PAN Mingjun WANG Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment ChangeNanjing University of Information Science and Technology Key Laboratory of Mesoscale Severe Weather/Ministry of Education and School of Atmospheric Sciences Nanjing University

Assimilation configurations have significant impacts on analysis results and subsequent forecasts. A squall line system that occurred on 23 April 2007 over southern China was used to investigate the impacts of the data assimilation frequency of radar data on analyses and forecasts. A three-dimensional variational system was used to assimilate radial velocity data,and a cloud analysis system was used for reflectivity assimilation with a 2-h assimilation window covering the initial stage of the squall line. Two operators of radar reflectivity for cloud analyses corresponding to single-and double-moment schemes were used. In this study, we examined the sensitivity of assimilation frequency using 10-, 20-, 30-, and 60-min assimilation intervals. The results showed that analysis fields were not consistent with model dynamics and microphysics in general;thus, model states, including dynamic and microphysical variables, required approximately 20 min to reach a new balance after data assimilation in all experiments. Moreover, a 20-min data assimilation interval generally produced better forecasts for both single-and double-moment schemes in terms of equitable threat and bias scores. We conclude that a higher data assimilation frequency can produce a more intense cold pool and rear inflow jets but does not necessarily lead to a better forecast.

关键词： cloud analysis radar data assimilation data assimilation interval

Blockchain-Based Trusted Electronic Records Preservation in cloud Storage

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Computers, Materials & Continua 2019年第1期58卷 135-151页

作者： Zhiliang Deng Yongjun Ren Yepeng Liu Xiang Yin Zixuan Shen Hye-Jin Kim School of Information and Control Nanjing University of Information Science&TechnologyNanjing210044China Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing210044China Jiangsu Engineering Center of Network Monitoring Nanjing University of Information Science&TechnologyNanjing210044China School of Computer and Software Nanjing University of Information Science&TechnologyNanjing210044China College of Information Engineering Yangzhou UniversityYangzhou225127China Business Administration Research Institute Sungshin W.UniversitySeoulKorea

cloud storage represents the trend of intensive,scale and specialization of information technology,which has changed the technical architecture and implementation method of electronic records management.Moreover,it will provide a convenient way to generate more advanced and efficient management of the electronic data records.However,in cloud storage environment,it is difficult to guarantee the trustworthiness of electronic records,which results in a series of severe challenges to electronic records management.Starting from the definition and specification of electronic records,this paper firstly analyzes the requirements of the trustworthiness in cloud storage during their long-term preservation according to the information security theory and subdivides the trustworthiness into the authenticity,integrity,usability,and reliability of electronic records in cloud storage.Moreover,this paper proposes the technology framework of preservation for trusted electronic records.Also,the technology of blockchain,proofs of retrievability,the open archival information system model and erasure code are adopted to protect these four security attributes,to guarantee the credibility of the electronic record.

关键词： Trusted electronic record blockchain cloud storage

Secure workflow scheduling in cloud environment using modified particle swarm optimization with scout adaptation

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International Journal of Modeling, Simulation, and Scientific Computing 2018年第1期9卷 74-95页

作者： P.Sanyasi Naidu Babita Bhagat Department of Computer Science and Engineering Gitam University Visakhapatnam 530045Andhra PradeshIndia Department of Computer Engineering Pillai HOC College of Engineering and TechnologyRasayaniKhalapur 410207MaharashtraIndia

In the distributed data-intensive computing environment,securely assigning tasks to appropriate machines is a big job scheduling problem.The complexity of this problem increases with the number of jobs and their job times.Several meta-heuristic algorithms including particle swarm optimization(PSO)technique and variable neighborhood particle swarm optimization(VNPSO)technique are employed to solve the problem to a certain extent.This paper proposes a modified PSO with scout adaptation(MPSO-SA)algorithm,which uses a cyclic term called mutation operator,to solve the job scheduling problem in the cloud environment.The comparative study between the proposed MPSO-SA scheduling mechanism and the conventional scheduling algorithms show that the proposed method decreases the probability of security risk on scheduling the jobs.

关键词： cloud scheduling meta-heuristic MPSO-SA GA PSO VNPSO

VARIATION OF THE INNER ELECTRONIC cloud IN A TWO-ELECTRON ATOMIC SYSTEM

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Science China Mathematics 1992年第1期35卷 91-99页

作者：鲍诚光 Division of Theoretical Physics Chinese Center of Advanced Science and Technology (World Laboratory) Beijing and Department of Physics Zhongshan University Guangzhou 510275 PRC

The variation of the inner electronic cloud of a two-electron system when the outer elec-tron is moving far away or coming close is investigated in this paper mainly by analyzingthe shape-density. The geometric character and features of internal motion of the ~1S^e heliumstates having different K--numbers have been shown, the mechanism for energy transfer andthe details of radial-radial correlation have been inspected. The motion of the inner electroniccloud as a whole is found to be strongly correlated with the motion of the outer electron.

关键词： inner electron cloud two-electron atomic system.