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The University of Jordan E-Learning Platform: State, Students’ Acceptance and Challenges
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作者 Tamara Almarabeh Hiba Mohammad +1 位作者 Rana Yousef Yousef Kh. Majdalawi 《Journal of Software Engineering and Applications》 2014年第12期999-1007,共9页
The rapid changes and increased complexity in today’s world present new challenges and put new demands on the education system. There has been generally a growing awareness of the necessity?to change and improve the ... The rapid changes and increased complexity in today’s world present new challenges and put new demands on the education system. There has been generally a growing awareness of the necessity?to change and improve the existing system towards online learning. Jordan is one of the distinguished countries in the Middle East with rapid progress in education and with advanced teaching and learning technologies. The University of Jordan is trying to exploit Information and Communication Technology (ICT) in education and moving forward by introducing the latest E-learning management systems (LMSs) to keep pace of technological revolution in the higher education. It is?important to find out the impact of E-learning management system in the University of Jordan,?examine the students’ acceptance for this new system and address the challenges facing the students while using the E-learning management system and these are what this paper is trying to do. 展开更多
关键词 MOODLE e-learning BLACKBOARD Technology ACCEPTANCE Model JORDAN
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Construction of e-learning platform
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作者 WU Yi-qiang TAN Jun-shan +1 位作者 HE Wei WANG Chu-zheng 《通讯和计算机(中英文版)》 2009年第12期33-37,共5页
关键词 电子学习 平台 LNTERNET 信息技术 知识更新 网络教育 学习方法 学习观念
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A Stacking Machine Learning Model for Student Performance Prediction Based on Class Activities in E-Learning
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作者 Mohammad Javad Shayegan Rosa Akhtari 《Computer Systems Science & Engineering》 2024年第5期1251-1272,共22页
After the spread of COVID-19,e-learning systems have become crucial tools in educational systems worldwide,spanning all levels of education.This widespread use of e-learning platforms has resulted in the accumulation ... After the spread of COVID-19,e-learning systems have become crucial tools in educational systems worldwide,spanning all levels of education.This widespread use of e-learning platforms has resulted in the accumulation of vast amounts of valuable data,making it an attractive resource for predicting student performance.In this study,we aimed to predict student performance based on the analysis of data collected from the OULAD and Deeds datasets.The stacking method was employed for modeling in this research.The proposed model utilized weak learners,including nearest neighbor,decision tree,random forest,enhanced gradient,simple Bayes,and logistic regression algorithms.After a trial-and-error process,the logistic regression algorithm was selected as the final learner for the proposed model.The results of experiments with the above algorithms are reported separately for the pass and fail classes.The findings indicate that the accuracy of the proposed model on the OULAD dataset reached 98%.Overall,the proposed method improved accuracy by 4%on the OULAD dataset. 展开更多
关键词 STACKING e-learning student performance prediction machine learning CLASSIFICATION
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Efficient Intelligent E-Learning Behavior-Based Analytics of Student’s Performance Using Deep Forest Model
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作者 Raed Alotaibi Omar Reyad Mohamed Esmail Karar 《Computer Systems Science & Engineering》 2024年第5期1133-1147,共15页
E-learning behavior data indicates several students’activities on the e-learning platform such as the number of accesses to a set of resources and number of participants in lectures.This article proposes a new analyt... E-learning behavior data indicates several students’activities on the e-learning platform such as the number of accesses to a set of resources and number of participants in lectures.This article proposes a new analytics systemto support academic evaluation for students via e-learning activities to overcome the challenges faced by traditional learning environments.The proposed e-learning analytics system includes a new deep forest model.It consists of multistage cascade random forests with minimal hyperparameters compared to traditional deep neural networks.The developed forest model can analyze each student’s activities during the use of an e-learning platform to give accurate expectations of the student’s performance before ending the semester and/or the final exam.Experiments have been conducted on the Open University Learning Analytics Dataset(OULAD)of 32,593 students.Our proposed deep model showed a competitive accuracy score of 98.0%compared to artificial intelligence-based models,such as ConvolutionalNeuralNetwork(CNN)and Long Short-TermMemory(LSTM)in previous studies.That allows academic advisors to support expected failed students significantly and improve their academic level at the right time.Consequently,the proposed analytics system can enhance the quality of educational services for students in an innovative e-learning framework. 展开更多
关键词 e-learning behavior data student evaluation artificial intelligence machine learning
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E-learning在医学教育领域内的实践与研究 被引量:1
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作者 董慧琳 仇菲 《中国医药导报》 CAS 2023年第25期77-80,共4页
科学技术与医学教育的发展,对医学教育的过程及途径提出新要求。电子学习(E-learning)作为一种新型教学方式,早已在教育、培训等领域广泛应用,尤其是在国外。在国内医学教育领域中,E-learning也得到迅速发展,并发挥积极作用。随着这种... 科学技术与医学教育的发展,对医学教育的过程及途径提出新要求。电子学习(E-learning)作为一种新型教学方式,早已在教育、培训等领域广泛应用,尤其是在国外。在国内医学教育领域中,E-learning也得到迅速发展,并发挥积极作用。随着这种应用趋势的展开,不少学者对此进行相关研究。本文在对E-learning方式进行解读的基础上,追溯其发展历程与在医学教育领域内的应用现状,对相关的国内外研究资料进行回顾,为E-learning在国内医学教育的实践研究提供建设性启示。 展开更多
关键词 e-learning 医学教育 教学改革 自主学习
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基于E-learning的翻转课堂模式在消化系统疾病实习教学中的应用效果 被引量:2
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作者 李健 高建淑 +1 位作者 赵可可 高鸿亮 《新疆医科大学学报》 CAS 2023年第10期1408-1410,共3页
目的 探讨基于E-learning的翻转课堂模式在消化系统疾病实习教学中的应用效果。方法 选取2021年8月至2022年7月在新疆医科大学第一临床医学院就读的200名临床医学专业学生,采用随机数字表法分为研究组(100名)与对照组(100名)。研究组采... 目的 探讨基于E-learning的翻转课堂模式在消化系统疾病实习教学中的应用效果。方法 选取2021年8月至2022年7月在新疆医科大学第一临床医学院就读的200名临床医学专业学生,采用随机数字表法分为研究组(100名)与对照组(100名)。研究组采用基于E-learning的翻转课堂模式教学,对照组实施传统教学模式教学。比较两组学生自我评价、教师对学生能力评价以及理论考核和临床操作考核成绩。结果 研究组学生学习兴趣、学习效率、学习信心、总体满意度的自我评价均高于对照组(P均<0.05);带教教师对研究组学生自主学习能力、团队协作能力、临床思维能力、临床技能能力评价均高于对照组(P均<0.05);研究组学生理论考核和临床操作考核成绩均高于对照组(P均<0.05)。结论 基于E-learning的翻转课堂模式可有效培养学生临床思维和操作能力,提升消化系统疾病实习教学效率及教学效果。 展开更多
关键词 e-learning 翻转课堂 传统教学 消化系统疾病 实习教学
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Application of GNSS-PPP on Dynamic Deformation Monitoring of Offshore Platforms 被引量:1
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作者 YU Li-na XIONG Kuan +3 位作者 GAO Xi-feng LI Zhi FAN Li-long ZHANG Kai 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期352-361,共10页
The real-time dynamic deformation monitoring of offshore platforms under environmental excitation is crucial to their safe operation.Although Global Navigation Satellite System-Precise Point Positioning(GNSS-PPP)has b... The real-time dynamic deformation monitoring of offshore platforms under environmental excitation is crucial to their safe operation.Although Global Navigation Satellite System-Precise Point Positioning(GNSS-PPP)has been considered for this purpose,its monitoring accuracy is relatively low.Moreover,the influence of background noise on the dynamic monitoring accuracy of GNSS-PPP remains unclear.Hence,it is imperative to further validate the feasibility of GNSS-PPP for deformation monitoring of offshore platforms.To address these concerns,vibration table tests with different amplitudes and frequencies are conducted.The results demonstrate that GNSS-PPP can effectively monitor horizontal vibration displacement as low as±30 mm,which is consistent with GNSS-RTK.Furthermore,the spectral characteristic of background noise in GNSS-PPP is similar to that of GNSS-RTK(Real Time Kinematic).Building on this observation,an improved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN)has been proposed to de-noise the data and enhance the dynamic monitoring accuracy of GNSS-PPP.Field monitoring application research is also undertaken,successfully extracting and analyzing the dynamic deformation of an offshore platform structure under environmental excitation using GNSS-PPP monitoring in conjunction with improved CEEMDAN de-noising.By comparing the de-noised dynamic deformation trajectories of the offshore platform during different periods,it is observed that the platform exhibits reversible alternating vibration responses under environmental excitation,with more pronounced displacement deformation in the direction of load action.The research results confirm the feasibility and potential of GNSS-PPP for dynamic deformation monitoring of offshore platforms. 展开更多
关键词 GNSS-PPP offshore platform dynamic deformation monitoring improved CEEMDAN de-noising
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Blockchain-Based Decentralized Authentication Model for IoT-Based E-Learning and Educational Environments
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作者 Osama A.Khashan Sultan Alamri +3 位作者 Waleed Alomoush Mutasem K.Alsmadi Samer Atawneh Usama Mir 《Computers, Materials & Continua》 SCIE EI 2023年第5期3133-3158,共26页
In recent times,technology has advanced significantly and is currently being integrated into educational environments to facilitate distance learning and interaction between learners.Integrating the Internet of Things... In recent times,technology has advanced significantly and is currently being integrated into educational environments to facilitate distance learning and interaction between learners.Integrating the Internet of Things(IoT)into education can facilitate the teaching and learning process and expand the context in which students learn.Nevertheless,learning data is very sensitive and must be protected when transmitted over the network or stored in data centers.Moreover,the identity and the authenticity of interacting students,instructors,and staff need to be verified to mitigate the impact of attacks.However,most of the current security and authentication schemes are centralized,relying on trusted third-party cloud servers,to facilitate continuous secure communication.In addition,most of these schemes are resourceintensive;thus,security and efficiency issues arise when heterogeneous and resource-limited IoT devices are being used.In this paper,we propose a blockchain-based architecture that accurately identifies and authenticates learners and their IoT devices in a decentralized manner and prevents the unauthorized modification of stored learning records in a distributed university network.It allows students and instructors to easily migrate to and join multiple universities within the network using their identity without the need for user re-authentication.The proposed architecture was tested using a simulation tool,and measured to evaluate its performance.The simulation results demonstrate the ability of the proposed architecture to significantly increase the throughput of learning transactions(40%),reduce the communication overhead and response time(26%),improve authentication efficiency(27%),and reduce the IoT power consumption(35%)compared to the centralized authentication mechanisms.In addition,the security analysis proves the effectiveness of the proposed architecture in resisting various attacks and ensuring the security requirements of learning data in the university network. 展开更多
关键词 Blockchain decentralized authentication Internet of Things(IoT) e-learning IoT security
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Real Objects Understanding Using 3D Haptic Virtual Reality for E-Learning Education
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作者 Samia Allaoua Chelloug Hamid Ashfaq +4 位作者 Suliman A.Alsuhibany Mohammad Shorfuzzaman Abdulmajeed Alsufyani Ahmad Jalal Jeongmin Park 《Computers, Materials & Continua》 SCIE EI 2023年第1期1607-1624,共18页
In the past two decades,there has been a lot of work on computer vision technology that incorporates many tasks which implement basic filtering to image classification.Themajor research areas of this field include obj... In the past two decades,there has been a lot of work on computer vision technology that incorporates many tasks which implement basic filtering to image classification.Themajor research areas of this field include object detection and object recognition.Moreover,wireless communication technologies are presently adopted and they have impacted the way of education that has been changed.There are different phases of changes in the traditional system.Perception of three-dimensional(3D)from two-dimensional(2D)image is one of the demanding tasks.Because human can easily perceive but making 3D using software will take time manually.Firstly,the blackboard has been replaced by projectors and other digital screens so such that people can understand the concept better through visualization.Secondly,the computer labs in schools are now more common than ever.Thirdly,online classes have become a reality.However,transferring to online education or e-learning is not without challenges.Therefore,we propose a method for improving the efficiency of e-learning.Our proposed system consists of twoand-a-half dimensional(2.5D)features extraction using machine learning and image processing.Then,these features are utilized to generate 3D mesh using ellipsoidal deformation method.After that,3D bounding box estimation is applied.Our results show that there is a need to move to 3D virtual reality(VR)with haptic sensors in the field of e-learning for a better understanding of real-world objects.Thus,people will have more information as compared to the traditional or simple online education tools.We compare our result with the ShapeNet dataset to check the accuracy of our proposed method.Our proposed system achieved an accuracy of 90.77%on plane class,85.72%on chair class,and car class have 72.14%.Mean accuracy of our method is 70.89%. 展开更多
关键词 Artificial intelligence e-learning online education system computer vision virtual reality 3D haptic
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Student’s Health Exercise Recognition Tool for E-Learning Education
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作者 Tamara al Shloul Madiha Javeed +4 位作者 Munkhjargal Gochoo Suliman AAlsuhibany Yazeed Yasin Ghadi Ahmad Jalal Jeongmin Park 《Intelligent Automation & Soft Computing》 SCIE 2023年第1期149-161,共13页
Due to the recently increased requirements of e-learning systems,multiple educational institutes such as kindergarten have transformed their learning towards virtual education.Automated student health exercise is a di... Due to the recently increased requirements of e-learning systems,multiple educational institutes such as kindergarten have transformed their learning towards virtual education.Automated student health exercise is a difficult task but an important one due to the physical education needs especially in young learners.The proposed system focuses on the necessary implementation of student health exercise recognition(SHER)using a modified Quaternion-basedfilter for inertial data refining and data fusion as the pre-processing steps.Further,cleansed data has been segmented using an overlapping windowing approach followed by patterns identification in the form of static and kinematic signal patterns.Furthermore,these patterns have been utilized to extract cues for both patterned signals,which are further optimized using Fisher’s linear discriminant analysis(FLDA)technique.Finally,the physical exercise activities have been categorized using extended Kalmanfilter(EKF)-based neural networks.This system can be implemented in multiple educational establishments including intelligent training systems,virtual mentors,smart simulations,and interactive learning management methods. 展开更多
关键词 e-learning exercise recognition online physical education student’s healthcare
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Dynamic Analysis of a 10 MW Floating Offshore Wind Turbine Considering the Tower and Platform Flexibility
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作者 GAO Shan ZHANG Lixian +3 位作者 SHI Wei WANG Wenhua WANG Bin LI Xin 《Journal of Ocean University of China》 CAS CSCD 2024年第2期358-370,共13页
Recently,semisubmersible floating offshore wind turbine technologies have received considerable attention.For the coupled simulation of semisubmersible floating offshore wind energy,the platform is usually considered ... Recently,semisubmersible floating offshore wind turbine technologies have received considerable attention.For the coupled simulation of semisubmersible floating offshore wind energy,the platform is usually considered a rigid model,which could affect the calculation accuracy of the dynamic responses.The dynamic responses of a TripleSpar floating offshore wind turbine equipped with a 10 MW offshore wind turbine are discussed herein.The simulation of a floating offshore wind turbine under regular waves,white noise waves,and combined wind-wave conditions is conducted.The effects of the tower and platform flexibility on the motion and force responses of the TripleSpar semisubmersible floating offshore wind turbine are investigated.The results show that the flexibility of the tower and platform can influence the dynamic responses of a TripleSpar semisubmersible floating offshore wind turbine.Considering the flexibility of the tower and platform,the tower and platform pitch motions markedly increased compared with the fully rigid model.Moreover,the force responses,particularly for tower base loads,are considerably influenced by the flexibility of the tower and platform.Thus,the flexibility of the tower and platform for the coupled simulation of floating offshore wind turbines must be appropriately examined. 展开更多
关键词 floating offshore wind turbine TripleSpar semisubmersible platform rigidity and flexibility platform coupled simulation
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Sedimentary build-ups of pre-salt isolated carbonate platforms and formation of deep-water giant oil fields in Santos Basin,Brazil
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作者 DOU Lirong WEN Zhixin +7 位作者 WANG Zhaoming HE Zhengjun SONG Chengpeng CHEN Ruiyin YANG Xiaofa LIU Xiaobing LIU Zuodong CHEN Yanyan 《Petroleum Exploration and Development》 SCIE 2024年第4期949-962,共14页
In response to the problems of unclear distribution of deep-water pre-salt carbonate reservoirs and formation conditions of large oil fields in the Santos passive continental margin basin,based on comprehensive utiliz... In response to the problems of unclear distribution of deep-water pre-salt carbonate reservoirs and formation conditions of large oil fields in the Santos passive continental margin basin,based on comprehensive utilization of geological,seismic,and core data,and reconstruction of Early Cretaceous prototype basin and lithofacies paleogeography,it is proposed for the first time that the construction of pre-salt carbonate build-ups was controlled by two types of isolated platforms:inter-depression fault-uplift and intra-depression fault-high.The inter-depression fault-uplift isolated platforms are distributed on the present-day pre-salt uplifted zones between depressions,and are built on half-and fault-horst blocks that were inherited and developed in the early intra-continental and inter-continental rift stages.The late intra-continental rift coquinas of the ITP Formation and the early inter-continental rift microbial limestones of the BVE Formation are continuously constructed;intra-depression fault-high isolated platforms are distributed in the current pre-salt depression zones,built on the uplifted zones formed by volcanic rock build-ups in the early prototype stage of intra-continental rifts,and only the BVE microbial limestones are developed.Both types of limestones formed into mound-shoal bodies,that have the characteristics of large reservoir thickness and good physical properties.Based on the dissection of large pre-salt oil fields discovered in the Santos Basin,it has been found that both types of platforms could form large-scale combined structural-stratigraphic traps,surrounded by high-quality lacustrine and lagoon source rocks at the periphery,and efficiently sealed by thick high-quality evaporite rocks above,forming the optimal combination of source,reservoir and cap in the form of“lower generation,middle storage,and upper cap”,with a high degree of oil and gas enrichment.It has been found that the large oil fields are all bottom water massive oil fields with a unified pressure system,and they are all filled to the spill-point.The future exploration is recommended to focus on the inter-depression fault-uplift isolated platforms in the western uplift zone and the southern section of eastern uplift zones,as well as intra-depression fault-high isolated platforms in the central depression zone.The result not only provides an important basis for the advanced selection of potential play fairways,bidding of new blocks,and deployment of awarded exploration blocks in the Santos Basin,but also provides a reference for the global selection of deep-water exploration blocks in passive continental margin basins. 展开更多
关键词 Santos Basin passive continental marginal basin deep water inter-depression fault-uplift isolated carbonate platform intra-depression fault-high carbonate isolated platform giant oil fields
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Renewable Biomass as a Platform for Preparing Green Chemistry
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作者 Qiaoguang Li Puyou Jia +1 位作者 Ying Luo Yue Liu 《Journal of Renewable Materials》 EI CAS 2024年第2期325-328,共4页
1 About the Special Issue Editor Qiaoguang Li is an associate professor and master’s supervisor in the Department of College of Chemistry and Chemical Engineering,Zhongkai University of Agriculture and Engineering.He... 1 About the Special Issue Editor Qiaoguang Li is an associate professor and master’s supervisor in the Department of College of Chemistry and Chemical Engineering,Zhongkai University of Agriculture and Engineering.He received his PhD from Institute of Chemical Industry of Forestry Products,Chinese Academy of Forestry in 2018.He has been focusing his research on the chemical basis and application of natural resources.He has published nearly 30 international peer reviewed papers and applied for 10 patents. 展开更多
关键词 BIOMASS platform PATENT
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Dynamic Coupling Analysis of Semisubmersible Platform Float-over Method for Docking Case
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作者 DING Hongyan QIN Licheng +2 位作者 ZHANG Puyang SONG Zhengrong XIE Weiwei 《Journal of Ocean University of China》 CAS CSCD 2024年第2期345-357,共13页
In this paper,the multi-body coupled dynamic characteristics of a semisubmersible platform and an HYSY 229 barge were investigated.First,coupled hydrodynamic analysis of the HYSY 229 barge and the semisubmersible plat... In this paper,the multi-body coupled dynamic characteristics of a semisubmersible platform and an HYSY 229 barge were investigated.First,coupled hydrodynamic analysis of the HYSY 229 barge and the semisubmersible platform was performed.Relevant hydrodynamic parameters were obtained using the retardation function method of three-dimensional frequency-domain potential flow theory.The results of the hydrodynamic analysis were highly consistent with the test findings,verifying the accuracy of the multifloating hydrodynamic coupling analysis,and key hydrodynamic parameters were solved for different water depths and the coupling effect.According to the obtained results,the hydrodynamic influence was the largest in shallow waters when the coupling effect was considered.Furthermore,the coupled motion equation combined with viscous damping,fender system,and mooring system was established,and the hydrodynamics,floating body motion,and dynamic response of the fender system were analyzed.Motion analysis revealed good agreement among the surge,sway,and yaw motions of the two floating bodies.However,when the wave period reached 10 s,the motion of the two floating bodies showed severe shock,and a relative motion was also observed.Therefore,excessive constraints should be added between the two floating bodies during construction to ensure construction safety.The numerical analysis and model test results of the semisubmersible platform and HYSY 229 barge at a water depth of 42 m and sea conditions of 0°,45°,and 90° were in good agreement,and the error was less than 5%.The maximum movement of the HYSY 229 barge reached 2.61 m in the sway direction,whereas that of the semisubmersible platform was 2.11 m.During construction,excessive constraints should be added between the two floating bodies to limit their relative movement and ensure construction safety. 展开更多
关键词 float-over method semisubmersible platform coupling hydrodynamic fender system time-domain analysis
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A Coordinate-Free Approach to the Design of Generalized Griffis-Duffy Platforms
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作者 Chengwei Shen Xu Pei +1 位作者 Lubin Hang Jingjun Yu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期95-103,共9页
Architectural singularity belongs to the Type II singularity,in which a parallel manipulator(PM)gains one or more degrees of freedom and becomes uncontrollable.PMs remaining permanently in a singularity are beneficial... Architectural singularity belongs to the Type II singularity,in which a parallel manipulator(PM)gains one or more degrees of freedom and becomes uncontrollable.PMs remaining permanently in a singularity are beneficial for linearto-rotary motion conversion.Griffis-Duffy(GD)platform is a mobile structure admitting a Bricard motion.In this paper,we present a coordinate-free approach to the design of generalized GD platforms,which consists in determining the shape and attachment of both the moving platform and the fixed base.The generalized GD platform is treated as a combination of six coaxial single-loop mechanisms under the same constraints.Owing to the inversion,hidden in the geometric structure of these single-loop mechanisms,the mapping from a line to a circle establishes the geometric transformation between the fixed base and the moving platform based on the center of inversion,and describes the shape and attachment of the generalized GD platform.Moreover,the center of inversion not only identifies the location of rotation axis,but also affects the shape of the platform mechanism.A graphical construction of generalized GD platforms using inversion,proposed in the paper,provides geometrically feasible solutions of the manipulator design for the requirement of the location of rotation axis. 展开更多
关键词 Generalized Griffis-Duffy platforms SELF-MOTION INVERSION Coordinate-free determination Manipulator design
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Experimental Study on Towing Characteristics of Composite Bucket Wellhead Platform
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作者 ZHANG Pu-yang LIU Ying-fei +2 位作者 LE Cong-huan DING Hong-yan BAI Yu 《China Ocean Engineering》 SCIE EI CSCD 2024年第3期531-542,共12页
With the rapid development of large-scale development of marginal oilfields in China,simple wellhead platforms that are simple in structure and easy to install have become an inevitable choice in the process of oilfie... With the rapid development of large-scale development of marginal oilfields in China,simple wellhead platforms that are simple in structure and easy to install have become an inevitable choice in the process of oilfield development.However,traditional simple wellhead platforms are often discarded after a single use.In pursuit of a more costeffective approach to developing marginal oilfields,this paper proposes a new offshore oil field development facility—an integrated bucket foundation for wellhead platform.To verify the safety of its towing behavior and obtain the dynamic response characteristics of the structure,this paper takes a bucket integrated bucket foundation for wellhead platform with a diameter of 40 m as the research object.By combining physical model tests and numerical simulations,it analyzes the static stability and dynamic response characteristics of the structure during towing,complete with the effects of the draft,wave height,wave period,and towing point height,which produce the dynamic responses of the structure under different influence factors,such as roll angle,pitch angle,heave acceleration and towing force as well as the sensibility to transport variables.The results show that the integrated bucket foundation for wellhead platform is capable of self-floating towing,and its movement is affected by the local environment,which will provide a reference for actual projects. 展开更多
关键词 composite bucket foundation wellhead platform air flotation towing model test
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Application of Time-Tracking Platform in the Reperfusion Treatment of Patients with Acute Ischemic Stroke in Primary Hospitals
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作者 Yaojie Cai Yan Chen +1 位作者 Feng Fu Yuping He 《Journal of Biosciences and Medicines》 2024年第7期230-238,共9页
Objective To explore the application effect of time tracking platform in improving the reperfusion treatment of patients with acute ischemic stroke in primary hospitals. Methods and Results Patients with acute ischemi... Objective To explore the application effect of time tracking platform in improving the reperfusion treatment of patients with acute ischemic stroke in primary hospitals. Methods and Results Patients with acute ischemic stroke who carried out emergency intravenous thrombolysis and arterial thrombectomy in our hospital in 2021, 2022 and 2023 were selected. The time tracking mode was implemented, and the patients were recorded at each time node of the hospital and the whole-process digital management was conducted. Compared the mean DNT (Door to Needle Time) of intravenous thrombolysis in emergency stroke patients in 2021, 2022 and 2023, the total number of hospital cases within 4.5 h of onset, the total number of thrombolysis cases within 4.5 h of onset, the number of intravenous thrombolysis in 60 minutes of acute ischemic stroke, and the number of thrombolysis cases. The results show that from 2021 to 2023 our emergency stroke patients with intravenous thrombolysis average DNT shortened year by year, to the hospital within 4.5 h after the onset of the difference is statistically significant (all P < 0.05) conclusion through the application of stroke time tracking platform, is beneficial to shorten the treatment time of each link, can effectively reduce the hospital time delay, improve the rate of thrombolysis, improve the reperfusion of stroke centers in primary hospitals. 展开更多
关键词 Time-Tracking platform Acute Ischemic Stroke THROMBOLYSIS THROMBECTOMY
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Quantum circuit-based proxy blind signatures:A novel approach and experimental evaluation on the IBM quantum cloud platform
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作者 娄小平 昝慧茹 徐雪娇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期247-253,共7页
This paper presents a novel approach to proxy blind signatures in the realm of quantum circuits,aiming to enhance security while safeguarding sensitive information.The main objective of this research is to introduce a... This paper presents a novel approach to proxy blind signatures in the realm of quantum circuits,aiming to enhance security while safeguarding sensitive information.The main objective of this research is to introduce a quantum proxy blind signature(QPBS)protocol that utilizes quantum logical gates and quantum measurement techniques.The QPBS protocol is constructed by the initial phase,proximal blinding message phase,remote authorization and signature phase,remote validation,and de-blinding phase.This innovative design ensures a secure mechanism for signing documents without revealing the content to the proxy signer,providing practical security authentication in a quantum environment under the assumption that the CNOT gates are securely implemented.Unlike existing approaches,our proposed QPBS protocol eliminates the need for quantum entanglement preparation,thus simplifying the implementation process.To assess the effectiveness and robustness of the QPBS protocol,we conduct comprehensive simulation studies in both ideal and noisy quantum environments on the IBM quantum cloud platform.The results demonstrate the superior performance of the QPBS algorithm,highlighting its resilience against repudiation and forgeability,which are key security concerns in the realm of proxy blind signatures.Furthermore,we have established authentic security thresholds(82.102%)in the presence of real noise,thereby emphasizing the practicality of our proposed solution. 展开更多
关键词 proxy blind signature quantum circuits quantum computation IBM quantum cloud platform
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Simulation of wave scattering over a floating platform in the ocean with a coupled CFD-IBM model
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作者 Pengxuan Luo Jingxin Zhang +1 位作者 Yongyong Cao Shaohong Song 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第3期157-161,共5页
A numerical study of linear wave scattering over a floating platform has been simulated by an efficient numericalmodel in this letter.The non-hydrostatic model is used to simulate the free surface and the uneven botto... A numerical study of linear wave scattering over a floating platform has been simulated by an efficient numericalmodel in this letter.The non-hydrostatic model is used to simulate the free surface and the uneven bottom.For thesolid body modelling,the immersed boundary method(IBM)is implemented by introducing a virtual boundaryforce into the momentum equations to emulate the boundary conditions.This implementation enhances theability of the model to simulate interactions between waves and floating structures.A numerical case involvingwave interactions with a floating platform is studied to validate the numerical model.By simulating the wavepropagation,the numerical model captures the variation of the wave scattering very well,which verifies theperformance of the numerical model and the robust strategy of the IBM. 展开更多
关键词 Non-hydrostatic model Immersed boundary method Wave structure interaction Floating platform
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Research on the Legal Framework of Content Regulations for Network Platforms
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作者 Zhang Yin Liao Xinyue 《Contemporary Social Sciences》 2024年第1期137-155,共19页
In the era of the Internet,various network platforms have evolved into new hubs for information dissemination.Currently,China has established a platform-centered content regulation framework,wherein platforms proactiv... In the era of the Internet,various network platforms have evolved into new hubs for information dissemination.Currently,China has established a platform-centered content regulation framework,wherein platforms proactively enforce content regulations in accordance with legal censorship obligations.Additionally,platform policies and user agreements augment their authority in content regulation.The platforms can achieve cost-effective and highly efficient content regulation by leveraging their strategic advantages enabled by their own technical capabilities and extensive coverage.The platform self-regulation model,however,still faces challenges.First,accurately evaluating content remains a formidable task;second,ensuring effective platform publicity through self-regulation poses difficulties;third,users may potentially face disadvantages due to the platform’s right of self-regulation;and fourth,digital copyright owners face challenges when defending digital copyright disputes under the safe harbor rule.Therefore,it is imperative to establish,review,and revise the legal framework for content regulation of network platforms in order to enhance the efficiency of their governance systems.The formulation of the legal framework for content regulation of network platforms may encompass the following aspects:rationalizing obligations pertaining to platform content regulations,enhancing supervision over platform self-regulation,and establishing a dual-track responsibility system for digital copyright content regulation.This will ensure a harmonious balance among public interests,users’personal rights and interests,and commercial benefits through regulating the content on network platforms. 展开更多
关键词 content regulations platform self-regulation legal framework
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