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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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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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Performance of composite foundations with different load transfer platforms and substratum stiffness over silty clay
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作者 ZHANG Shuming LIU Yan +3 位作者 YUAN Shengyang LIU Xianfeng JIANG Guanlu LIU Junyan 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1761-1774,共14页
The semi-rigid pile-supported composite foundation is widely used in highway projects due to its effectiveness in increasing the bearing capacity and stability of foundations.It is crucial to understand the stress dis... The semi-rigid pile-supported composite foundation is widely used in highway projects due to its effectiveness in increasing the bearing capacity and stability of foundations.It is crucial to understand the stress distribution across the embankment width and the behaviour of unreinforced foundations.Thus,five centrifuge tests were conducted to examine the bearing and deformation behaviours of NPRS(Non-Connected Piled Raft Systems)and GRPS(GeosyntheticReinforced Pile-Supported systems)with varying substratum stiffness,then a comparative analysis was conducted on embankment settlement,pressures underneath the embankments,and axial forces along the piles.The results indicated that greater substratum stiffness correlates with reduced settlement and deformation at various depths.Deformation occurring 5 meters from the embankment toe includes settlement in NPRS and upward movement in GRPS.The potential sliding surface is primarily located within the embankment in NPRS,whereas it may extend through both the embankment and foundation in GRPS.The pile-soil stress ratio and efficiency in NPRS are higher than in GRPS across the embankment.The axial force borne by end-bearing piles is significantly greater than that by floating piles.As the buried depth increases,the axial force in GRPS initially rises then declines,whereas in NPRS,it remains relatively constant within a certain range before decreasing.This study aids in assessing the applicability of composite foundations in complex railway environments and provides a reference for procedural measures under similar conditions. 展开更多
关键词 Centrifuge modelling Composite foundation Failure mode Load transfer platform SUBSTRATUM STIFFNESS Silty clay
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Predicting Purchasing Behavior on E-Commerce Platforms: A Regression Model Approach for Understanding User Features that Lead to Purchasing
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作者 Abraham Jallah Balyemah Sonkarlay J. Y. Weamie +2 位作者 Jiang Bin Karmue Vasco Jarnda Felix Jwakdak Joshua 《International Journal of Communications, Network and System Sciences》 2024年第6期81-103,共23页
This research introduces a novel approach to improve and optimize the predictive capacity of consumer purchase behaviors on e-commerce platforms. This study presented an introduction to the fundamental concepts of the... This research introduces a novel approach to improve and optimize the predictive capacity of consumer purchase behaviors on e-commerce platforms. This study presented an introduction to the fundamental concepts of the logistic regression algorithm. In addition, it analyzed user data obtained from an e-commerce platform. The original data were preprocessed, and a consumer purchase prediction model was developed for the e-commerce platform using the logistic regression method. The comparison study used the classic random forest approach, further enhanced by including the K-fold cross-validation method. Evaluation of the accuracy of the model’s classification was conducted using performance indicators that included the accuracy rate, the precision rate, the recall rate, and the F1 score. A visual examination determined the significance of the findings. The findings suggest that employing the logistic regression algorithm to forecast customer purchase behaviors on e-commerce platforms can improve the efficacy of the approach and yield more accurate predictions. This study serves as a valuable resource for improving the precision of forecasting customers’ purchase behaviors on e-commerce platforms. It has significant practical implications for optimizing the operational efficiency of e-commerce platforms. 展开更多
关键词 E-Commerce platform Purchasing Behavior Prediction Logistic Regression Algorithm
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Research on the Audio Publishing of Classical Books Based on the Theory of Business Model Canvas: Taking Romance of the Three Kingdoms in Digital Audio Platforms as an Example
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作者 Ding Qin Liu Mengzhi 《Contemporary Social Sciences》 2024年第1期58-74,共17页
Visual media have dominated sensory communications for decades,and the resulting“visual hegemony”leads to the call for the“auditory return”in order to achieve a holistic balance in cultural acceptance.Romance of t... Visual media have dominated sensory communications for decades,and the resulting“visual hegemony”leads to the call for the“auditory return”in order to achieve a holistic balance in cultural acceptance.Romance of the Three Kingdoms,a classic literary work in China,has received significant attention and promotion from leading audio platforms.However,the commercialization of digital audio publishing faces unprecedented challenges due to the mismatch between the dissemination of long-form content on digital audio platforms and the current trend of short and fast information reception.Drawing on the Business Model Canvas Theory and taking Romance of the Three Kingdoms as the main focus of analysis,this paper argues that the construction of a business model for the audio publishing of classical books should start from three aspects:the user evaluation of digital audio platforms,the establishment of value propositions based on the“creative transformation and innovative development”principle,and the improvement of the audio publishing infrastructure to ensure the healthy operation and development of the digital audio platforms and consequently improve their current state of development and expand the boundaries of cultural heritage. 展开更多
关键词 Romance of the Three Kingdoms audio publishing Business Model Canvas digital audio platforms
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Transforming Digital Experiences: The Evolution of Digital Experience Platforms (DXPs) from Monoliths to Microservices: A Practical Guide
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作者 Sourabh Sethi Sarah Panda 《Journal of Computer and Communications》 2024年第2期142-155,共14页
The research aims to explore the transition from monolithic Digital Experience Platforms (DXPs) to Microservices-based DXPs, addressing scalability challenges. The study systematically decomposes monolithic structures... The research aims to explore the transition from monolithic Digital Experience Platforms (DXPs) to Microservices-based DXPs, addressing scalability challenges. The study systematically decomposes monolithic structures into Microservices, emphasizing business capability and subdomain decomposition. Concrete insights, challenges, and solutions encountered during this transformation process are presented. The research contributes valuable insights into the challenges and benefits of adopting Microservices in DXPs. Results highlight the importance of architectural patterns and strategic scaling dimensions for improved performance and scalability. The case study on Backbase’s Engagement Banking Platform showcases successful implementation, providing flexibility, integration, and efficient development in the evolving DXP landscape. 展开更多
关键词 Digital Experience platforms (DXPs) Microservices Software Evolution Distributed Systems Architectural Patterns
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Research on Network Security Level Protection Measurement Strategy in the Context of Cloud Platforms
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作者 Lin Ma 《Journal of Electronic Research and Application》 2024年第3期221-229,共9页
Platforms facilitate information exchange,streamline resources,and reduce production and management costs for companies.However,some viral information may invade and steal company resources,or lead to information leak... Platforms facilitate information exchange,streamline resources,and reduce production and management costs for companies.However,some viral information may invade and steal company resources,or lead to information leakage.For this reason,this paper discusses the standards for cybersecurity protection,examines the current state of cybersecurity management and the risks faced by cloud platforms,expands the time and space for training on cloud platforms,and provides recommendations for measuring the level of cybersecurity protection within cloud platforms in order to build a solid foundation for them. 展开更多
关键词 Cloud platform Cyber security Level protection measurement
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Structural Design Study of Air-Dropped Unmanned Maritime Mobile Search and Rescue Platforms
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作者 Zhiming Feng Lingzhe Kong Zhongyu Cui 《Journal of Electronic Research and Application》 2024年第3期234-242,共9页
In order to improve the efficiency and safety of search and rescue(SAR)at sea,this paper proposes a kind of emergency rapid rescue unmanned craft(air-dropped unmanned maritime motorized search and rescue platform)that... In order to improve the efficiency and safety of search and rescue(SAR)at sea,this paper proposes a kind of emergency rapid rescue unmanned craft(air-dropped unmanned maritime motorized search and rescue platform)that can be delivered by a large transport aircraft.This paper studies the structural design scheme of the platform,and the main scale of the platform,the choice of power system and the impact resistance performance are considered in the design process to ensure its rapid response and effective rescue capability under complex sea conditions.Simulation results show that the platform can withstand the impact of air injection into the water and the shipboard equipment can operate normally under the impact load,thus verifying the feasibility and safety of the design.This study serves to improve the maritime search and rescue system and enhance the oceanic emergency response capability. 展开更多
关键词 Maritime search and rescue Unmanned maritime platform Maritime airdrop Impact resistance simulation
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Research trends in methods for controlling macro-micro motion platforms 被引量:2
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作者 Lufan Zhang Pengqi Zhang +1 位作者 Boshi Jiang Heng Yan 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2023年第3期64-78,共15页
With ongoing economic,scientific,and technological developments,the electronic devices used in daily lives are developing toward precision and miniaturization,and so the demand for high-precision manufacturing machine... With ongoing economic,scientific,and technological developments,the electronic devices used in daily lives are developing toward precision and miniaturization,and so the demand for high-precision manufacturing machinery is expanding.The most important piece of equipment in modern high-precision manufacturing is the macro-micro motion platform(M3P),which offers high speed,precision,and efficiency and has macro-micro motion coupling characteristics due to its mechanical design and composition of its driving components.Therefore,the design of the control system is crucial for the overall precision of the platform;conventional proportional–integral–derivative control cannot meet the system requirements,and so M3Ps are the subject of a growing range of modern control strategies.This paper begins by describing the development history of M3Ps,followed by their platform structure and motion control system components,and then in-depth assessments of the macro,micro,and macro-micro control systems.In addition to examining the advantages and disadvantages of current macro-micro motion control,recent technological breakthroughs are noted.Finally,based on existing problems,future directions for M3P control systems are given,and the present conclusions offer guidelines for future work on M3Ps. 展开更多
关键词 Macro-micro motion platform Precision positioning Control method Piezoelectric driver Voice coil motor
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Typhoon Case Comparison Analysis Between Heterogeneous Many-Core and Homogenous Multicore Supercomputing Platforms
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作者 LIU Xin YU Xiaolin +5 位作者 ZHAO Haoran HAN Qiqi ZHANG Jie WANG Chengzhi MA Weiwei XU Da 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第2期324-334,共11页
In this paper,a typical experiment is carried out based on a high-resolution air-sea coupled model,namely,the coupled ocean-atmosphere-wave-sediment transport(COAWST)model,on both heterogeneous many-core(SW)and homoge... In this paper,a typical experiment is carried out based on a high-resolution air-sea coupled model,namely,the coupled ocean-atmosphere-wave-sediment transport(COAWST)model,on both heterogeneous many-core(SW)and homogenous multicore(Intel)supercomputing platforms.We construct a hindcast of Typhoon Lekima on both the SW and Intel platforms,compare the simulation results between these two platforms and compare the key elements of the atmospheric and ocean modules to reanalysis data.The comparative experiment in this typhoon case indicates that the domestic many-core computing platform and general cluster yield almost no differences in the simulated typhoon path and intensity,and the differences in surface pressure(PSFC)in the WRF model and sea surface temperature(SST)in the short-range forecast are very small,whereas a major difference can be identified at high latitudes after the first 10 days.Further heat budget analysis verifies that the differences in SST after 10 days are mainly caused by shortwave radiation variations,as influenced by subsequently generated typhoons in the system.These typhoons generated in the hindcast after the first 10 days attain obviously different trajectories between the two platforms. 展开更多
关键词 heterogeneous many-core supercomputing platform homogenous multicore supercomputing platform comparison analysis typhoon case
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Assessment of Aged Offshore Jacket Type Platforms Considering Environmental Loads and Degradation Parameters
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作者 Yazeed Al-Radhi Farzad Hejazi +1 位作者 Azmi Abdulkarim Ali Feroozi 《Structural Durability & Health Monitoring》 EI 2023年第2期89-113,共25页
Offshore steel structures are a common investment in oil and gas industries operating in shallow to medium depth seas.These structures have become increasingly popular since the mid-19th century,with a typical design ... Offshore steel structures are a common investment in oil and gas industries operating in shallow to medium depth seas.These structures have become increasingly popular since the mid-19th century,with a typical design life of 30-50 years.Despite their popularity,the structural integrity of existing offshore structures remains a controversial topic.Environmental loads and material degradation have been identified as significant factors that can compromise the structural integrity of offshore structures.To address this issue,this study aims to investigate the reserved strength capacity of a selected offshore structure located in the Malaysian Seas.The study will explore the effect of oceanographic data,variations in vertical load,and corrosion on the structure’s main members.To determine the impact of each variable on the reserved strength ratio(RSR)of the structure,several pushover analyses were conducted with different variables.Previous literature has shown little or no relationship between seawater wave height,gravity loads,and corrosion allowance on submerged steel members and the RSR of offshore structures.However,this study aims tofill this gap in knowledge by examining these variables’effects on the RSR of offshore structures.The study’sfindings indicate that even a slight increase in wave height can significantly impact the structure’s RSR due to the increase in lateral loading,potentially leading to severe damage to structural components and the foundation model.Additionally,gravity loads had an adverse effect on the RSR of the structure when more than double the vertical load was added.Corrosion allowance was also found to impact the RSR,particularly when assuming significant wall thickness corrosion in primary members.Overall,thefindings of this study have important implications for the design and maintenance of offshore structures.The results suggest that engineers and operators should pay close attention to the potential impacts of environmental loads,such as wave height and gravity loads,and material degradation,such as corrosion allowance,on the structural integrity of offshore structures.This information can be used to optimize the design and maintenance of offshore structures,leading to safer and more efficient operations. 展开更多
关键词 ASSESSMENT life extension offshore platforms platform reserved strength ratio global ultimate strength analysis
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Corpus of Carbonate Platforms with Lexical Annotations for Named Entity Recognition
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作者 Zhichen Hu Huali Ren +3 位作者 Jielin Jiang Yan Cui Xiumian Hu Xiaolong Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期91-108,共18页
An obviously challenging problem in named entity recognition is the construction of the kind data set of entities.Although some research has been conducted on entity database construction,the majority of them are dire... An obviously challenging problem in named entity recognition is the construction of the kind data set of entities.Although some research has been conducted on entity database construction,the majority of them are directed at Wikipedia or the minority at structured entities such as people,locations and organizational nouns in the news.This paper focuses on the identification of scientific entities in carbonate platforms in English literature,using the example of carbonate platforms in sedimentology.Firstly,based on the fact that the reasons for writing literature in key disciplines are likely to be provided by multidisciplinary experts,this paper designs a literature content extraction method that allows dealing with complex text structures.Secondly,based on the literature extraction content,we formalize the entity extraction task(lexicon and lexical-based entity extraction)for entity extraction.Furthermore,for testing the accuracy of entity extraction,three currently popular recognition methods are chosen to perform entity detection in this paper.Experiments show that the entity data set provided by the lexicon and lexical-based entity extraction method is of significant assistance for the named entity recognition task.This study presents a pilot study of entity extraction,which involves the use of a complex structure and specialized literature on carbonate platforms in English. 展开更多
关键词 Named entity recognition carbonate platform corpus entity extraction english literature detection
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A Comparative Study on the Communication of“Friendly Shandong”Official Account on Different Short Video Platforms
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作者 CHEN Fangying LI Xichao 《Journal of Landscape Research》 2023年第3期47-50,共4页
Taking“Friendly Shandong”official account as an example,the relevant data of the account on the four platforms of Tiktok,Kwai,Bilibili and Little Red Book were comparatively analyzed to study the influence of short ... Taking“Friendly Shandong”official account as an example,the relevant data of the account on the four platforms of Tiktok,Kwai,Bilibili and Little Red Book were comparatively analyzed to study the influence of short video on the communication of Shandong tourism image.The research mainly included two aspects:fan persona features and interactive effects.Through comparative study,it will provide a reference for the operation team of“Friendly Shandong”official account to spread the tourism image of Shandong with different platforms. 展开更多
关键词 Friendly Shandong Short video platform COMMUNICATION Comparative study
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The Dilemma of Women’s Voices in the Post-Epidemic Era:Misconceptions of Feminism on Digital Media Platforms-The Example of Sina Weibo
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作者 LIU Yuewen 《Psychology Research》 2023年第2期88-103,共16页
Weibo,one of China’s largest digital media platforms,has become a major platform for women’s voices to fight for equality.However,misconceptions of feminism on Weibo have become obstacles to women’s voices,for whic... Weibo,one of China’s largest digital media platforms,has become a major platform for women’s voices to fight for equality.However,misconceptions of feminism on Weibo have become obstacles to women’s voices,for which the platforms did not post women’s views prominently.From the perspective of women themselves,this paper adopted a questionnaire to study the misunderstanding of feminism and its impact on women’s expression on Weibo. 展开更多
关键词 FEMINISM women’s voices digital media platforms the post-epidemic era
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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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Propping Up Platforms
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作者 ZHANG SHASHA 《ChinAfrica》 2023年第2期46-47,共2页
“Accept my invitation to Temu to help me to get my gift!”If you have ever received this invitation link from your friends,congratulations!You are now a“team”member of online marketplace Temu,whose name is derived ... “Accept my invitation to Temu to help me to get my gift!”If you have ever received this invitation link from your friends,congratulations!You are now a“team”member of online marketplace Temu,whose name is derived from its slogan-Team Up,Price Down. 展开更多
关键词 INVITATION platform MARKET
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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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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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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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