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Multi-dimensional multiplexing optical secret sharing framework with cascaded liquid crystal holograms 被引量:3
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作者 Keyao Li Yiming Wang +6 位作者 Dapu Pi Baoli Li Haitao Luan Xinyuan Fang Peng Chen Yanqing Lu Min Gu 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第1期28-35,共8页
Secret sharing is a promising technology for information encryption by splitting the secret information into different shares.However,the traditional scheme suffers from information leakage in decryption process since... Secret sharing is a promising technology for information encryption by splitting the secret information into different shares.However,the traditional scheme suffers from information leakage in decryption process since the amount of available information channels is limited.Herein,we propose and demonstrate an optical secret sharing framework based on the multi-dimensional multiplexing liquid crystal(LC)holograms.The LC holograms are used as spatially separated shares to carry secret images.The polarization of the incident light and the distance between different shares are served as secret keys,which can significantly improve the information security and capacity.Besides,the decryption condition is also restricted by the applied external voltage due to the variant diffraction efficiency,which further increases the information security.In implementation,an artificial neural network(ANN)model is developed to carefully design the phase distribution of each LC hologram.With the advantage of high security,high capacity and simple configuration,our optical secret sharing framework has great potentials in optical encryption and dynamic holographic display. 展开更多
关键词 holographic encryption optical secret sharing cascaded liquid crystal hologram multi-dimensional multiplexing
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Intelligent 6G Wireless Network with Multi-Dimensional Information Perception 被引量:1
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作者 YANG Bei LIANG Xin +3 位作者 LIU Shengnan JIANG Zheng ZHU Jianchi SHE Xiaoming 《ZTE Communications》 2023年第2期3-10,共8页
Intelligence and perception are two operative technologies in 6G scenarios.The intelligent wireless network and information perception require a deep fusion of artificial intelligence(AI)and wireless communications in... Intelligence and perception are two operative technologies in 6G scenarios.The intelligent wireless network and information perception require a deep fusion of artificial intelligence(AI)and wireless communications in 6G systems.Therefore,fusion is becoming a typical feature and key challenge of 6G wireless communication systems.In this paper,we focus on the critical issues and propose three application scenarios in 6G wireless systems.Specifically,we first discuss the fusion of AI and 6G networks for the enhancement of 5G-advanced technology and future wireless communication systems.Then,we introduce the wireless AI technology architecture with 6G multidimensional information perception,which includes the physical layer technology of multi-dimensional feature information perception,full spectrum fusion technology,and intelligent wireless resource management.The discussion of key technologies for intelligent 6G wireless network networks is expected to provide a guideline for future research. 展开更多
关键词 6G wireless network artificial intelligence multi-dimensional information perception full spectrum fusion
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Patient satisfaction and follow-up adherence to glaucoma case management clinic in China 被引量:1
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作者 Hao Lin Hu-Jie Lu +3 位作者 Wen-Zhe Zhou Shu-Shu Zuo Yan-Yan Chen Shao-Dan Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期73-81,共9页
AIM:To assess glaucoma patient satisfaction and follow-up adherence in case management and identify associated predictors to improve healthcare quality and patient outcomes.METHODS:In this cross-sectional study,a tota... AIM:To assess glaucoma patient satisfaction and follow-up adherence in case management and identify associated predictors to improve healthcare quality and patient outcomes.METHODS:In this cross-sectional study,a total of 119 patients completed a Patient Satisfaction Questionnaire-18 and a sociodemographic questionnaire.Clinical data was obtained from the case management system.Follow-up adherence was defined as completing each follow-up within±30d of the scheduled time set by ophthalmologists during the study period.RESULTS:Average satisfaction scored 78.65±7,with an average of 4.39±0.58 across the seven dimensions.Age negatively correlated with satisfaction(P=0.008),whilst patients with follow-up duration of 2 or more years reported higher satisfaction(P=0.045).Multivariate logistics regression analysis revealed that longer follow-up durations were associated with lower follow-up adherence(OR=0.97,95%CI,0.95-1.00,P=0.044).Additionally,patients with suspected glaucoma(OR=2.72,95%CI,1.03-7.20,P=0.044)and those with an annual income over 100000 Chinese yuan demonstrated higher adherence(OR=5.57,95%CI,1.00-30.89,P=0.049).CONCLUSION:The case management model proves effective for glaucoma patients,with positive adherence rates.The implementation of this model can be optimized in the future based on the identified factors and extended to glaucoma patients in more hospitals. 展开更多
关键词 GLAUCOMA patient satisfaction follow-up adherence case management
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Envelope Method and More General New Global Structures of Solutions for Multi-dimensional Conservation Law
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作者 Gui-Qin Qiu Gao-Wei Cao +1 位作者 Xiao-Zhou Yang Yuan-An Zhao 《Communications on Applied Mathematics and Computation》 2023年第3期1180-1234,共55页
For the two-dimensional(2D)scalar conservation law,when the initial data contain two different constant states and the initial discontinuous curve is a general curve,then complex structures of wave interactions will b... For the two-dimensional(2D)scalar conservation law,when the initial data contain two different constant states and the initial discontinuous curve is a general curve,then complex structures of wave interactions will be generated.In this paper,by proposing and investigating the plus envelope,the minus envelope,and the mixed envelope of 2D non-selfsimilar rarefaction wave surfaces,we obtain and the prove the new structures and classifications of interactions between the 2D non-selfsimilar shock wave and the rarefaction wave.For the cases of the plus envelope and the minus envelope,we get and prove the necessary and sufficient criterion to judge these two envelopes and correspondingly get more general new structures of 2D solutions. 展开更多
关键词 Riemann problem Non-selfsimilar shock wave Non-selfsimilar rarefaction wave ENVELOPE multi-dimensional conservation law
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Research and Practice on the Multi-dimensional Course Goal Achievement Evaluation of Software Engineering
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作者 Ying Jiang Hongbin Wang Jiaman Ding 《计算机教育》 2023年第12期265-271,共7页
According to the standards of engineering education accreditation,the achievement paths and evaluation criteria of course goals are presented,aimed at the objectives of software engineering courses and the characteris... According to the standards of engineering education accreditation,the achievement paths and evaluation criteria of course goals are presented,aimed at the objectives of software engineering courses and the characteristics of hybrid teaching in Kunming University of Science and Technology.Then a multi-dimensional evaluation system for course goal achievement of software engineering is proposed.The practice’s results show that the multi-dimensional course goal achievement evaluation is helpful to the continuous improvement of course teaching,which can effectively support the evaluation of graduation outcomes. 展开更多
关键词 Software engineering Course goal achievement evaluation multi-dimensional
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An Ordinal Multi-Dimensional Classification(OMDC)for Predictive Maintenance
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作者 Pelin Yildirim Taser 《Computer Systems Science & Engineering》 SCIE EI 2023年第2期1499-1516,共18页
Predictive Maintenance is a type of condition-based maintenance that assesses the equipment's states and estimates its failure probability and when maintenance should be performed.Although machine learning techniq... Predictive Maintenance is a type of condition-based maintenance that assesses the equipment's states and estimates its failure probability and when maintenance should be performed.Although machine learning techniques have been frequently implemented in this area,the existing studies disregard to the nat-ural order between the target attribute values of the historical sensor data.Thus,these methods cause losing the inherent order of the data that positively affects the prediction performances.To deal with this problem,a novel approach,named Ordinal Multi-dimensional Classification(OMDC),is proposed for estimating the conditions of a hydraulic system's four components by taking into the natural order of class values.To demonstrate the prediction ability of the proposed approach,eleven different multi-dimensional classification algorithms(traditional Binary Relevance(BR),Classifier Chain(CC),Bayesian Classifier Chain(BCC),Monte Carlo Classifier Chain(MCC),Probabilistic Classifier Chain(PCC),Clas-sifier Dependency Network(CDN),Classifier Trellis(CT),Classifier Dependency Trellis(CDT),Label Powerset(LP),Pruned Sets(PS),and Random k-Labelsets(RAKEL))were implemented using the Ordinal Class Classifier(OCC)algorithm.Besides,seven different classification algorithms(Multilayer Perceptron(MLP),Support Vector Machine(SVM),k-Nearest Neighbour(kNN),Decision Tree(C4.5),Bagging,Random Forest(RF),and Adaptive Boosting(AdaBoost))were chosen as base learners for the OCC algorithm.The experimental results present that the proposed OMDC approach using binary relevance multi-dimensional classification methods predicts the conditions of a hydraulic system's multiple components with high accuracy.Also,it is clearly seen from the results that the OMDC models that utilize ensemble-based classification algorithms give more reliable prediction performances with an average Hamming score of 0.853 than the others that use traditional algorithms as base learners. 展开更多
关键词 Machine learning multi-dimensional classification ordinal classification predictive maintenance
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Data inversion of multi-dimensional magnetic resonance in porous media
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作者 Fangrong Zong Huabing Liu +1 位作者 Ruiliang Bai Petrik Galvosas 《Magnetic Resonance Letters》 2023年第2期127-139,I0004,共14页
Since its inception in the 1970s,multi-dimensional magnetic resonance(MR)has emerged as a powerful tool for non-invasive investigations of structures and molecular interactions.MR spectroscopy beyond one dimension all... Since its inception in the 1970s,multi-dimensional magnetic resonance(MR)has emerged as a powerful tool for non-invasive investigations of structures and molecular interactions.MR spectroscopy beyond one dimension allows the study of the correlation,exchange processes,and separation of overlapping spectral information.The multi-dimensional concept has been re-implemented over the last two decades to explore molecular motion and spin dynamics in porous media.Apart from Fourier transform,methods have been developed for processing the multi-dimensional time-domain data,identifying the fluid components,and estimating pore surface permeability via joint relaxation and diffusion spectra.Through the resolution of spectroscopic signals with spatial encoding gradients,multi-dimensional MR imaging has been widely used to investigate the microscopic environment of living tissues and distinguish diseases.Signals in each voxel are usually expressed as multi-exponential decay,representing microstructures or environments along multiple pore scales.The separation of contributions from different environments is a common ill-posed problem,which can be resolved numerically.Moreover,the inversion methods and experimental parameters determine the resolution of multi-dimensional spectra.This paper reviews the algorithms that have been proposed to process multidimensional MR datasets in different scenarios.Detailed information at the microscopic level,such as tissue components,fluid types and food structures in multi-disciplinary sciences,could be revealed through multi-dimensional MR. 展开更多
关键词 multi-dimensional MR Data inversion Porous media Inverse Laplace transform FOURIERTRANSFORM
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Loss to Specialized Cardiology Follow-Up in Adults Living with Congenital Heart Disease
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作者 Cheryl Dickson Danielle Osborn +3 位作者 David Baker Judith Fethney David S.Celermajer Rachael Cordina 《Congenital Heart Disease》 SCIE 2024年第1期49-63,共15页
Background:Much has been written about the loss to follow-up in the transition between pediatric and adult Congenital Heart Disease(CHD)care centers.Much less is understood about the loss to follow-up(LTF)after a succ... Background:Much has been written about the loss to follow-up in the transition between pediatric and adult Congenital Heart Disease(CHD)care centers.Much less is understood about the loss to follow-up(LTF)after a successful transition.This is critical too,as patients lost to specialised care are more likely to experience mor-bidity and premature mortality.Aims:To understand the prevalence and reasons for loss to follow-up(LTF)at a large Australian Adult Congenital Heart Disease(ACHD)centre.Methods:Patients with moderate or highly complex CHD and gaps in care of>3 years(defined as LTF)were identified from a comprehensive ACHD data-base.Structured telephone interviews examined current care and barriers to clinic attendance.Results:Overall,407(22%)of ACHD patients(n=1842)were LTF.The mean age at LTF was 31(SD 11.5)years and 54%were male;311(76%)were uncontactable.Compared to adults seen regularly,lost patients were younger,with a greater socio-economic disadvantage,and had less complex CHD(p<0.05 for all).We interviewed 59 patients(14%).The top 3 responses for care absences were“feeling well”(61%),losing track of time(36%),and not needing fol-low-up care(25%).Conclusions:A large proportion of the ACHD population becomes lost to specialised cardiac care,even after a successful transition.This Australian study reports younger age,moderate complexity defects,and socio-economic disadvantage as predictive of loss to follow-up.This study highlights the need for novel approaches to patient-centered service delivery even beyond the age of transition and resources to maintain patient engagement within the ACHD service. 展开更多
关键词 Loss to follow-up follow-up adult congenital heart disease lapse in care gaps in care care gaps care continuity ACHD predictors
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Essential role of postoperative follow-up in the management of clear cell sarcoma
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作者 Zi-Han Zhang Jin-Tao Guo +1 位作者 Ying Xie Si-Yu Sun 《World Journal of Clinical Cases》 SCIE 2024年第23期5299-5303,共5页
Clear cell sarcoma(CCS)is a rare melanocytic soft tissue sarcoma known for itspropensity to metastasize to the lymph nodes and typically has an unfavorableprognosis.Currently,surgical resection is the primary treatmen... Clear cell sarcoma(CCS)is a rare melanocytic soft tissue sarcoma known for itspropensity to metastasize to the lymph nodes and typically has an unfavorableprognosis.Currently,surgical resection is the primary treatment for localizedCCS,while radiotherapy and chemotherapy are preferred for metastatic cases.The roles of adjuvant chemotherapy,radiotherapy,and lymph node dissection arecontroversial.Although immunotherapy has emerged as a promising avenue inCCS treatment research,there are no established clinical standards for postoperativefollow-up.This editorial discusses a recent article by Liu et al,with afocus on current diagnostic modalities,treatment approaches,and the challengingprognosis associated with CCS.Our aim is to underscore the importance of longtermpatient follow-up in CCS management. 展开更多
关键词 Clear cell carcinoma DIAGNOSIS Treatment PROGNOSIS follow-up
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Multi-dimension and multi-modal rolling mill vibration prediction model based on multi-level network fusion
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作者 CHEN Shu-zong LIU Yun-xiao +3 位作者 WANG Yun-long QIAN Cheng HUA Chang-chun SUN Jie 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3329-3348,共20页
Mill vibration is a common problem in rolling production,which directly affects the thickness accuracy of the strip and may even lead to strip fracture accidents in serious cases.The existing vibration prediction mode... Mill vibration is a common problem in rolling production,which directly affects the thickness accuracy of the strip and may even lead to strip fracture accidents in serious cases.The existing vibration prediction models do not consider the features contained in the data,resulting in limited improvement of model accuracy.To address these challenges,this paper proposes a multi-dimensional multi-modal cold rolling vibration time series prediction model(MDMMVPM)based on the deep fusion of multi-level networks.In the model,the long-term and short-term modal features of multi-dimensional data are considered,and the appropriate prediction algorithms are selected for different data features.Based on the established prediction model,the effects of tension and rolling force on mill vibration are analyzed.Taking the 5th stand of a cold mill in a steel mill as the research object,the innovative model is applied to predict the mill vibration for the first time.The experimental results show that the correlation coefficient(R^(2))of the model proposed in this paper is 92.5%,and the root-mean-square error(RMSE)is 0.0011,which significantly improves the modeling accuracy compared with the existing models.The proposed model is also suitable for the hot rolling process,which provides a new method for the prediction of strip rolling vibration. 展开更多
关键词 rolling mill vibration multi-dimension data multi-modal data convolutional neural network time series prediction
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Long-term assessment of collagenase treatment for Dupuytren’s contracture:A 10-year follow-up study
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作者 Marco Passiatore Vitale Cilli +4 位作者 Adriano Cannella Ludovico Caruso Giulia Maria Sassara Giuseppe Taccardo Rocco De Vitis 《World Journal of Orthopedics》 2024年第4期355-362,共8页
BACKGROUND Enzymatic fasciotomy with collagenase clostridium histolyticum(CCH)has revolutionized the treatment for Dupuytren’s contracture(DC).Despite its benefits,the long-term outcomes remain unclear.This study pre... BACKGROUND Enzymatic fasciotomy with collagenase clostridium histolyticum(CCH)has revolutionized the treatment for Dupuytren’s contracture(DC).Despite its benefits,the long-term outcomes remain unclear.This study presented a comprehensive 10-year follow-up assessment of the enduring effects of CCH on patients with DC.AIM To compare the short-term(12 wk)and long-term(10 years)outcomes on CCH treatment in patients with DC.METHODS A cohort of 45 patients was treated with CCH at the metacarpophalangeal(MCP)joint and the proximal interphalangeal(PIP)joint and underwent systematic reevaluation.The study adhered to multicenter trial protocols,and assessments were conducted at 12 wk,7 years,and 10 years post-surgery.RESULTS Thirty-seven patients completed the 10-year follow-up.At 10 years,patients treated at the PIP joint exhibited a 100%recurrence.However,patients treated at the MCP joint only showed a 50%recurrence.Patient satisfaction varied,with a lower satisfaction reported in PIP joint cases.Recurrence exceeding 20 degrees on the total passive extension deficit was observed,indicating a challenge for sustained efficacy.Significant differences were noted between outcomes at the 7-year and 10-year intervals.CONCLUSION CCH demonstrated sustained efficacy when applied to the MCP joint.However,caution is warranted for CCH treatment at the PIP joint due to a high level of recurrence and low patient satisfaction.Re-intervention is needed within a decade of treatment. 展开更多
关键词 COLLAGENASE Xiapex Dupuytren disease Dupuytren recurrence Long term follow-up
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Environmental Impact Assessment Follow-Up of Seismic Survey Offshore Activities in Brazil
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作者 Fontes Nuno Eduardo Paulo Marcelo Montaño 《Journal of Environmental Protection》 2024年第2期141-155,共15页
Follow-up of environmental impacts is an integral part of the Environmental Impact Assessment (EIA) process, closely related to the effectiveness of the instrument. EIA follow-up has been receiving a lot of interest f... Follow-up of environmental impacts is an integral part of the Environmental Impact Assessment (EIA) process, closely related to the effectiveness of the instrument. EIA follow-up has been receiving a lot of interest from scientists and practitioners, though it is recognized as one of the weakest points of EIA systems globally. Also, EIA follow-up is influenced by the context, mainly in terms of the types of projects or activities and their related impacts on the environment. Therefore, the present paper is focused on the investigation of the follow-up stage applied to the activity of seismic survey coupled with offshore oil & gas exploitation in Brazil. Research was based on a qualitative approach that included document analysis and semi-structured interviews with analysts involved in EIA processes, and sought to generate evidence of effectiveness of the EIA follow-up as conducted by the Federal Environment Agency (Ibama) in order to situate the practice of follow-up in the broader context of international best practice principles. Based on the findings, it was concluded that, due to the peculiarities of offshore seismic survey, it is necessary to promote adaptations in the procedures for monitoring impacts in order to ensure proper alignment with the principles and conceptual foundations that guide EIA practice. Specifically, the timing of the execution of the activity imposes challenges for its integration into the “conventional” cycle that has guided the monitoring of the impacts in the EIA of projects. 展开更多
关键词 Environmental Impact Assessment follow-up follow-up Effectiveness Oil and Gas Offshore Seismic Survey
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The Study on College English Writing Based on Multi-dimensional Feed-back Mode
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作者 骆敏 徐敏娜 《海外英语》 2020年第12期273-274,共2页
The study constructed a multi-dimensional feedback mode integrating teacher feedback, peer feedback and network feedback, and applied it in the teaching of College English Writing. After 16 weeks of teaching, the stud... The study constructed a multi-dimensional feedback mode integrating teacher feedback, peer feedback and network feedback, and applied it in the teaching of College English Writing. After 16 weeks of teaching, the students in the multi-dimen-sional feedback class had significantly better overall writing scores than those in the teacher-feedback class. In terms of individual scores, multi-dimensional feedback played a better role in improving vocabulary and grammar than the class using teacher feed-back. However, there were no significant differences in the responses of writing tasks, coherence and cohesion. The study showed that most students were satisfied with the mode, believing that it was helpful to relieve writing anxiety, stimulate writing interest and improve their writing level. 展开更多
关键词 College English Writing multi-dimensional feedback MODE
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Structural Engineering of Hierarchical Aerogels Comprised of Multi-dimensional Gradient Carbon Nanoarchitectures for Highly Efficient Microwave Absorption 被引量:19
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作者 Yongpeng Zhao Xueqing Zuo +11 位作者 Yuan Guo Hui Huang Hao Zhang Ting Wang Ningxuan Wen Huan Chen Tianze Cong Javid Muhammad Xuan Yang Xinnan Wang Zeng Fan Lujun Pan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第9期344-363,共20页
Recently,multilevel structural carbon aerogels are deemed as attractive candidates for microwave absorbing materials.Nevertheless,excessive stack and agglomeration for low-dimension carbon nanomaterials inducing imped... Recently,multilevel structural carbon aerogels are deemed as attractive candidates for microwave absorbing materials.Nevertheless,excessive stack and agglomeration for low-dimension carbon nanomaterials inducing impedance mismatch are significant challenges.Herein,the delicate“3D helix-2D sheet-1D fiber-0D dot”hierarchical aerogels have been successfully synthesized,for the first time,by sequential processes of hydrothermal self-assembly and in-situ chemical vapor deposition method.Particularly,the graphene sheets are uniformly intercalated by 3D helical carbon nanocoils,which give a feasible solution to the mentioned problem and endows the as-obtained aerogel with abundant porous structures and better dielectric properties.Moreover,by adjusting the content of 0D core-shell structured particles and the parameters for growth of the 1D carbon nanofibers,tunable electromagnetic properties and excellent impedance matching are achieved,which plays a vital role in the microwave absorption performance.As expected,the optimized aerogels harvest excellent performance,including broad effective bandwidth and strong reflection loss at low filling ratio and thin thickness.This work gives valuable guidance and inspiration for the design of hierarchical materials comprised of dimensional gradient structures,which holds great application potential for electromagnetic wave attenuation. 展开更多
关键词 Hierarchical aerogels multi-dimensional gradient Carbon nanocoils Microwave absorption
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Seismic fragility analysis of highway bridges considering multi-dimensional performance limit state 被引量:16
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作者 Wang, Qi'ang Wu, Ziyan Liu, Shukui 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第2期185-193,共9页
Fragility analysis for highway bridges has become increasingly important in the risk assessment of highway transportation networks exposed to seismic hazards. This study introduces a methodology to calculate fragility... Fragility analysis for highway bridges has become increasingly important in the risk assessment of highway transportation networks exposed to seismic hazards. This study introduces a methodology to calculate fragility that considers multi-dimensional performance limit state parameters and makes a first attempt to develop fragility curves for a multi-span continuous (MSC) concrete girder bridge considering two performance limit state parameters: column ductility and transverse deformation in the abutments. The main purpose of this paper is to show that the performance limit states, which are compared with the seismic response parameters in the calculation of fragility, should be properly modeled as randomly interdependent variables instead of deterministic quantities. The sensitivity of fragility curves is also investigated when the dependency between the limit states is different. The results indicate that the proposed method can be used to describe the vulnerable behavior of bridges which are sensitive to multiple response parameters and that the fragility information generated by this method will be more reliable and likely to be implemented into transportation network loss estimation. 展开更多
关键词 highway bridge seismic hazard multi-dimensional performance limit state fragility curves sensitivity
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NEW STRUCTURES FOR NON-SELFSIMILAR SOLUTIONS OF MULTI-DIMENSIONAL CONSERVATION LAWS 被引量:4
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作者 杨小舟 魏涛 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1182-1202,共21页
In this article, we get non-selfsimilar elementary waves of the conservation laws in another kind of view, which is different from the usual self-similar transformation. The solution has different global structure. Th... In this article, we get non-selfsimilar elementary waves of the conservation laws in another kind of view, which is different from the usual self-similar transformation. The solution has different global structure. This article is divided into three parts. The first part is introduction. In the second part, we discuss non-selfsimilar elementary waves and their interactions of a class of twodimensional conservation laws. In this case, we consider the case that the initial discontinuity is parabola with u+ 〉 0, while explicit non-selfsirnilar rarefaction wave can be obtained. In the second part, we consider the solution structure of case u+ 〈 0. The new solution structures are obtained by the interactions between different elementary waves, and will continue to interact with other states. Global solutions would be very different from the situation of one dimension. 展开更多
关键词 non-selfsimilar shock wave rarefaction wave ENVELOPE multi-dimensional conservation laws
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Heavy oil component characterization with multi-dimensional unilateral NMR 被引量:4
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作者 Liu Huabing Xiao Lizhi +6 位作者 Guo Baoxin Zhang Zongfu Zong Fangrong Deng Feng Yu Huijun V.Anferov S.Anferova 《Petroleum Science》 SCIE CAS CSCD 2013年第3期402-407,共6页
Heavy oil is a complicated mixture and a potential resource and has attracted much attention since the end of last century. It is important to characterize the composition of heavy oil to enhance its recovery efficien... Heavy oil is a complicated mixture and a potential resource and has attracted much attention since the end of last century. It is important to characterize the composition of heavy oil to enhance its recovery efficiency. A designed unilateral Nuclear Magnetic Resonance (NMR) sensor with a Larmor frequency of 20 MHz and a well-defined constant gradient of 23.25 T/m was employed to acquire three- dimensional (3D) data for three heavy oil samples. The highly-constant gradient is advantageous for diffusion coefficient measurement of heavy oil. A fast data-implementation procedure including specially designed 3D pulse sequence and Inversion Laplace Transform (ILT) algorithm was adopted to process the data and extract 3D T1-D-T2 probability function. It indicates that NMR relaxometry and diffusometry are useful to characterize the components of heavy oil samples. NMR results were compared with independent measurements of fractionation and gas chromatography analysis. 展开更多
关键词 Heavy oil multi-dimensional NMR unilateral sensor
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Structure and cavitation erosion behavior of HVOF sprayed multi-dimensional WC-10Co4Cr coating 被引量:10
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作者 Xiang DING Xu-dong CHENG +3 位作者 Xiang YU Chao LI Cheng-qing YUAN Zhang-xiong DING 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第3期487-494,共8页
A new kind of multi-dimensional WC-10Co4Cr coating which is composed of nano,submicron,micron WC grains and CoCr alloy,was developed by high velocity oxy-fuel(HVOF)spraying.Porosity,microhardness,fracture toughness an... A new kind of multi-dimensional WC-10Co4Cr coating which is composed of nano,submicron,micron WC grains and CoCr alloy,was developed by high velocity oxy-fuel(HVOF)spraying.Porosity,microhardness,fracture toughness and cavitation erosion resistance of the multi-dimensional coating were investigated in comparison with the bimodal and nanostructured WC?10Co4Cr coatings.Moreover,the cavitation erosion behavior and mechanism of the multi-dimensional coating were explored.Results show that HVOF sprayed multi-dimensional WC-10Co4Cr coating possesses low porosity(≤0.32%)and high fracture toughness without obvious nano WC decarburization during spraying.Furthermore,it is discovered that the multi-dimensional WC-10Co4Cr coating exhibits the best cavitation erosion resistance which is enhanced by approximately 28%and 34%,respectively,compared with the nanostructured and bimodal coatings in fresh water.The superior cavitation resistance of multi-dimensional WC-10Co4Cr coating may originate from the unique micro?nano structure and excellent properties,which can effectively obstruct the formation and propagation of cavitation erosion cracks. 展开更多
关键词 WC-10Co4Cr cavitation erosion multi-dimensional coating high velocity oxy-fuel(HVOF)spraying MICROSTRUCTURE
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Analysis of multi-dimensional SAR for determining the thickness of thin sea ice in the Bohai Sea 被引量:5
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作者 张晰 张杰 +1 位作者 孟俊敏 苏腾飞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第3期681-698,共18页
Flat thin ice (<30 cm thick) is a common ice type in the Bohai Sea, China. Ice thickness detection is important to offshore exploration and marine transport in winter. Synthetic aperture radar (SAR) can be used to ... Flat thin ice (<30 cm thick) is a common ice type in the Bohai Sea, China. Ice thickness detection is important to offshore exploration and marine transport in winter. Synthetic aperture radar (SAR) can be used to acquire sea ice data in all weather conditions, and it is a useful tool for monitoring sea ice conditions. In this paper, we combine a multi-layered sea ice electromagnetic (EM) scattering model with a sea ice thermodynamic model to assess the determination of the thickness of flat thin ice in the Bohai Sea using SAR at different frequencies, polarization, and incidence angles. Our modeling studies suggest that co-polarization backscattering coefficients and the co-polarized ratio can be used to retrieve the thickness of flat thin ice from C- and X-band SAR, while the co-polarized correlation coefficient can be used to retrieve flat thin ice thickness from L-, C-, and X-band SAR. Importantly, small or moderate incidence angles should be chosen to avoid the effect of speckle noise. 展开更多
关键词 multi-dimensional SAR sea ice in the Bohai Sea flat thin ice thickness retrieval
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Low-Temperature Growing Anatase TiO2/SnO2 Multi-dimensional Heterojunctions at MXene Conductive Network for High-Efficient Perovskite Solar Cells 被引量:7
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作者 Linsheng Huang Xiaowen Zhou +7 位作者 Rui Xue Pengfei Xu Siliang Wang Chao Xu Wei Zeng Yi Xiong Hongqian Sang Dong Liang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第3期199-217,共19页
A multi-dimensional conductive heterojunction structure,composited by TiO2,SnO2,and Ti3C2TX MXene,is facilely designed and applied as electron transport layer in efficient and stable planar perovskite solar cells.Base... A multi-dimensional conductive heterojunction structure,composited by TiO2,SnO2,and Ti3C2TX MXene,is facilely designed and applied as electron transport layer in efficient and stable planar perovskite solar cells.Based on an oxygen vacancy scramble effect,the zero-dimensional anatase TiO2 quantum dots,surrounding on two-dimensional conductive Ti3C2TX sheets,are in situ rooted on three-dimensional SnO2 nanoparticles,constructing nanoscale TiO2/SnO2 heterojunctions.The fabrication is implemented in a controlled lowtemperature anneal method in air and then in N2 atmospheres.With the optimal MXene content,the optical property,the crystallinity of perovskite layer,and internal interfaces are all facilitated,contributing more amount of carrier with effective and rapid transferring in device.The champion power conversion efficiency of resultant perovskite solar cells achieves 19.14%,yet that of counterpart is just 16.83%.In addition,it can also maintain almost 85%of its initial performance for more than 45 days in 30–40%humidity air;comparatively,the counterpart declines to just below 75%of its initial performance. 展开更多
关键词 In situ fabrication multi-dimensional heterojunction Oxygen vacancy scramble effect Electron transport layer Perovskite solar cells
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