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Physical and numerical modeling of a framed anti-sliding structure for a mountainous railway line
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作者 QIU Ruizhe LIU Kaiwen +3 位作者 YANG Zhixiang MA Chiyuan XIAO Jian SU Qian 《Journal of Southeast University(English Edition)》 2025年第1期12-19,共8页
To ensure the operational safety of railways in the landslide-prone areas of mountainous regions,a large-scale model test and numerical simulation were conducted to study the bending moment distribution,internal force... To ensure the operational safety of railways in the landslide-prone areas of mountainous regions,a large-scale model test and numerical simulation were conducted to study the bending moment distribution,internal force distribution,deformation development,and crack propagation characteristics of a framed anti-sliding structure(FAS)under landslide thrust up to the point of failure.Results show that the maximum bending moment and its increase rate in the fore pile are greater than those in the rear pile,with the maximum bending moment of the fore pile approximately 1.1 times that of the rear pile.When the FAS fails,the displacement at the top of the fore pile is significantly greater,about 1.27 times that of the rear pile in the experiment.Major cracks develop at locations corresponding to the peak bending moments.Small transverse cracks initially appear on the upper surface at the intersection between the primary beam and rear pile and then spread to the side of the structure.At the failure stage,major cracks are observed at the pil-beam intersections and near the anchor points.Strengthening flexural stiffness at intersections where major cracks occur can improve the overall thrust-deformation coordination of the FAS,thereby maximizing its performance. 展开更多
关键词 mountainous railway SLOPE framed anti-sliding structure model test finite element modeling mechanical responses
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Corrigendum to“Meta databases of steel frame buildings for surrogate modelling and machine learning-based feature importance analysis”[Journal of Resilient Cities and Structures Volume 3 Issue 1(2024)20-43]
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作者 Delbaz Samadian Jawad Fayaz +2 位作者 Imrose B.Muhit Annalisa Occhipinti Nashwan Dawood 《Resilient Cities and Structures》 2025年第1期124-124,共1页
The authors regret that the original publication of this paper did not include Jawad Fayaz as a co-author.After further discussions and a thorough review of the research contributions,it was agreed that his significan... The authors regret that the original publication of this paper did not include Jawad Fayaz as a co-author.After further discussions and a thorough review of the research contributions,it was agreed that his significant contributions to the foundational aspects of the research warranted recognition,and he has now been added as a co-author. 展开更多
关键词 machine learning meta databases jawad fayaz surrogate modelling feature importance analysis steel frame buildings
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Evaluation of the fishbone model in simulating the seismic response of multistory reinforced concrete moment-resisting frames 被引量:4
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作者 Qu Zhe Gong Ting +1 位作者 Li Qiqi Wang Tao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第2期315-330,共16页
The fishbone model is a simplified numerical model for moment-resisting frames that is capable of modelling the effects of column-beam strength and stiffness ratios. The applicability of the fishbone model in simulati... The fishbone model is a simplified numerical model for moment-resisting frames that is capable of modelling the effects of column-beam strength and stiffness ratios. The applicability of the fishbone model in simulating the seismic responses of reinforced concrete moment-resisting frames of different sets of column-beam strength and stiffness ratios are evaluated through nonlinear static, dynamic and incremental dynamic analysis on six prototype buildings of 4-, 8-and 12-stories. The results show that the fishbone model is practically accurate enough for reinforced concrete frames, although the assumption of equal joint rotation does not hold in all cases. In addition to the ground motion characteristics and the number of stories in the structures, the accuracy of the model also varies with the column-beam stiffness and strength ratios. The model performs better for strong column-weak beam frames, in which the lateral drift patterns are better controlled by the continuous stiffness provided by the strong columns. When the inelastic deformation is large, the accuracy of the model may be subjected to large record-to-record variability. This is especially the case for frames of weak columns. 展开更多
关键词 FISHBONE model reinforced concrete frame strong column-weak beam column-beam stiffness ratio incremental dynamic analysis
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Frame erasure concealment in wideband speech coding based on large hidden Markov model
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作者 王仕奎 汤一彬 +1 位作者 尤红岩 吴镇扬 《Journal of Southeast University(English Edition)》 EI CAS 2009年第2期152-155,共4页
Frame erasure concealment is studied to solve the problem of rapid speech quality reduction due to the loss of speech parameters during speech transmission. A large hidden Markov model is applied to model the immittan... Frame erasure concealment is studied to solve the problem of rapid speech quality reduction due to the loss of speech parameters during speech transmission. A large hidden Markov model is applied to model the immittance spectral frequency (ISF) parameters in AMR-WB codec to optimally estimate the lost ISFs based on the minimum mean square error (MMSE) rule. The estimated ISFs are weighted with the ones of their previous neighbors to smooth the speech, resulting in the actual concealed ISF vectors. They are used instead of the lost ISFs in the speech synthesis on the receiver. Comparison is made between the speech concealed by this algorithm and by Annex I of G. 722. 2 specification, and simulation shows that the proposed concealment algorithm can lead to better performance in terms of frequency-weighted spectral distortion and signal-to-noise ratio compared to the baseline method, with an increase of 2.41 dB in signal-to-noise ratio (SNR) and a reduction of 0. 885 dB in frequency-weighted spectral distortion. 展开更多
关键词 frame erasure concealment wideband speech large hidden Markov model immittance spectral frequency(ISF) parameter
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Nonlinear damage model for seismic damage assessment of reinforced concrete frame members and structures 被引量:1
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作者 Shuijing Xiao Longhe Xu Xiao Lu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2018年第5期949-962,共14页
A nonlinear damage model based on the combination of deformation and hysteretic energy and its validation with experiments are presented.Also,a combination parameter is defined to consider the mutual effect of deforma... A nonlinear damage model based on the combination of deformation and hysteretic energy and its validation with experiments are presented.Also,a combination parameter is defined to consider the mutual effect of deformation and hysteretic energy for different types of components in different loading stages.Four reinforced concrete (RC) columns are simulated and analyzed using the nonlinear damage model.The results indicate that the damage evolution evaluated by the model agrees well with the experimental phenomenon.Furthermore,the seismic damage evolution of a six-story RC frame was analyzed,revealing four typical failure modes according to the interstory drift distribution of the structure;the damage values calculated using the nonlinear damage model agree well with the four typical failure modes. 展开更多
关键词 RC frame structure NONLINEAR DAMAGE model DAMAGE evolution COMBINATION PARAMETER Hysteretic energy
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Application of time series modeling to a national reference frame realization 被引量:1
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作者 D.Fazilova Sh.Ehgamberdiev S.Kuzin 《Geodesy and Geodynamics》 2018年第4期281-287,共7页
This paper presents an option for modern dynamic terrestrial reference system realization in Uzbekistan for user needs. An additive model is explored to predict patterns of time series and investigate means of constru... This paper presents an option for modern dynamic terrestrial reference system realization in Uzbekistan for user needs. An additive model is explored to predict patterns of time series and investigate means of constructing forecast time series models in the future. The main components(trend, periodical, and irregular) of the KIUB(DORIS) and KIT3, TASH, MADK, and MTAL(GNSS) international stations coordinate time series were investigated. It was shown that seasonal nonlinear trends occurred both in the height(U) component of all stations and the east(E) component of high mountainous stations such as MTAL and MADK. The seasonal periodical portion of the time series determined from the additive model has a complicated pattern for all sites and can be explained as both hydrological signals in the region and improvement of observational quality. Amplitudes of the best-fitting sinusoids in the North component ranged between 1.73 and 8.76 mm; the East component ranged between 0.82 and 11.92 mm; and the Up component ranged between 3.11 and 40.81 mm. Regression analysis of the irregular portion of the height component of the two techniques at the Kitab station using tropospheric parameters(pressure and temperature) was confirmed as only 57% of the stochastic portion of the time series. 展开更多
关键词 Terrestrial dynamic reference frame Time series analysis Forecasting model
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PHYSICAL MODELLING OF ISOTHERMAL DIE FORGING PROCESS OF Ti-ALLOY STRUCTURAL AIR-FRAME PART WITH ETYPE CROSS-SECTION AND VARYING THICKNESS RIB 被引量:4
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作者 Z. K. Yao H. Z. Cuo +1 位作者 M. Wang F. Lan and P. F. Feng (Northwestern Polytechnical University, Xi’ an 710072, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期401-405,共5页
Isothermal flashless die forging process of Ti - alloy structural air - frame part with varying thickness rib has been modelled in this paper.The results of present study show that a upside - down trapezoid rib would... Isothermal flashless die forging process of Ti - alloy structural air - frame part with varying thickness rib has been modelled in this paper.The results of present study show that a upside - down trapezoid rib would be formed and buckling would occure as blank is reduced,if the thickness of billet is maller than or equal to the thickness of rib. During modelling process of structural air frame part with E type cross - section rib, the saddle or lap would be formed finally at the middle of transverse rib between ribs with increase in deformation.If metal is allowed to flow out at confluence of longitudinal and transverse rib, the lop defect would be eliminated,, but a pipe cavity is obvious on corresponding loca- tion of blank. of defect formation depends on distance of metal flow ,friction,temperature homoge- neity of the blank and complexity of the part. 展开更多
关键词 Ti alloy air-frame part physical modelling
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Extended intrinsic mean spin tensor for turbulence modelling in non-inertial frame of reference
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作者 黄于宁 马晖扬 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第11期1463-1475,共13页
We investigate the role of extended intrinsic mean spin tensor introduced in this work for turbulence modelling in a non-inertial frame of reference. It is described by the Euclidean group of transformations and, in p... We investigate the role of extended intrinsic mean spin tensor introduced in this work for turbulence modelling in a non-inertial frame of reference. It is described by the Euclidean group of transformations and, in particular, its significance and importance in the approach of the algebraic Reynolds stress modelling, such as in a nonlinear K-ε model. To this end and for illustration of the effect of extended intrinsic spin tensor on turbulence modelling, we examine several recently developed nonlinear K-ε models and compare their performance in predicting the homogeneous turbulent shear flow in a rotating frame of reference with LES data. Our results and analysis indicate that, only if the deficiencies of these models and the like be well understood and properly corrected, may in the near future, more sophisticated nonlinear K-ε models be developed to better predict complex turbulent flows in a non-inertial frame of reference. 展开更多
关键词 turbulence modelling non-inertial frame of reference extended intrinsic mean spin tensor frame-dependent algebraic Reynolds stress models
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Meta databases of steel frame buildings for surrogate modelling and machine learning-based feature importance analysis 被引量:1
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作者 Delbaz Samadian Imrose B.Muhit +1 位作者 Annalisa Occhipinti Nashwan Dawood 《Resilient Cities and Structures》 2024年第1期20-43,共24页
Traditionally,nonlinear time history analysis(NLTHA)is used to assess the performance of structures under fu-ture hazards which is necessary to develop effective disaster risk management strategies.However,this method... Traditionally,nonlinear time history analysis(NLTHA)is used to assess the performance of structures under fu-ture hazards which is necessary to develop effective disaster risk management strategies.However,this method is computationally intensive and not suitable for analyzing a large number of structures on a city-wide scale.Surrogate models offer an efficient and reliable alternative and facilitate evaluating the performance of multiple structures under different hazard scenarios.However,creating a comprehensive database for surrogate mod-elling at the city level presents challenges.To overcome this,the present study proposes meta databases and a general framework for surrogate modelling of steel structures.The dataset includes 30,000 steel moment-resisting frame buildings,representing low-rise,mid-rise and high-rise buildings,with criteria for connections,beams,and columns.Pushover analysis is performed and structural parameters are extracted,and finally,incorporating two different machine learning algorithms,random forest and Shapley additive explanations,sensitivity and explain-ability analyses of the structural parameters are performed to identify the most significant factors in designing steel moment resisting frames.The framework and databases can be used as a validated source of surrogate modelling of steel frame structures in order for disaster risk management. 展开更多
关键词 Surrogate models Meta database Pushover analysis Steel moment resisting frames Sensitivity and explainability analyses Machine learning
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W-F STRUCTURE: A NEW ALGORITHM ON WIRE-FRAME MODELING
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作者 曾钢 王昌禄 《Journal of China University of Mining and Technology》 1996年第2期57-61,共5页
This paper advances a new algorithm oriented to geometry modeling (GM) by using frame model. The elemental data structure of frame model is the vertex. This afeoithm provides a general and rapid method. By this way,we... This paper advances a new algorithm oriented to geometry modeling (GM) by using frame model. The elemental data structure of frame model is the vertex. This afeoithm provides a general and rapid method. By this way,we can link the vertices to construct the elemental frame and need not consider the topological relation among vertices which consist of the concrete entity. Then, we can combine the elemental frames to complete frame modeling by using aided-line method referring to concrete entity. We will discuss two keystones in the paper. Then we give a 3D geometry modeling example based on wire-frame model using the new algorithm. 展开更多
关键词 CAD computer graphics frame model modeling system
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Model Experiment on Integral Seismic Behavior of Reinforced Concrete Frame with Split Columns
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作者 李忠献 景萌 +1 位作者 郝永昶 康谷贻 《Transactions of Tianjin University》 EI CAS 2005年第6期412-416,共5页
Based on a series of previous studies, an experiment on the integral seismic behavior of a 1/3 scaled model of two-bay and three-story reinforced concrete frame with split columns at lower two stories is performed und... Based on a series of previous studies, an experiment on the integral seismic behavior of a 1/3 scaled model of two-bay and three-story reinforced concrete frame with split columns at lower two stories is performed under cyclic loading. The original columns at lower two stories of the model frame are short columns and they are replaced by the split columns. The hysteresis curves between the horizontal cyclic load and the lateral displacement at the top of the model frame, indicate that under the cyclic loading, the model frame undergoes the process of cracking, yielding, and maximum loading before being destroyed at the ultimate load. They also indicate that the model frame has better ductility, and the ratio of the ultimate displacement to the yielding displacement, reaches 6.0. The yielding process of the model frame shows that for the frame with split columns, plastic hinges are generated at the ends of beams and then the columns begin yielding while the frame still possesses the bearing and deformation capacity. The design idea of directly changing the short column to long one in the reinforced concrete frame may be realized by replacing the short column with the split one. 展开更多
关键词 reinforced concrete frame seismic behavior split column short column model experiment
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Bilateral shear strength of rectangular frame column based on simplified space truss-arch model
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作者 董春敏 《Journal of Chongqing University》 CAS 2010年第4期195-200,共6页
To investigate the bilateral shear strength of rectangular frame column subjected to oblique horizontal load, we presented a simplified space truss-arch model developed from unilateral truss-arch model. Main parameter... To investigate the bilateral shear strength of rectangular frame column subjected to oblique horizontal load, we presented a simplified space truss-arch model developed from unilateral truss-arch model. Main parameters in the new model were the cross-sectional area, transverse reinforcement raito, axial load, and material strength of the column. The reduction coefficient of concrete sterength owing to the severe cracking of column was also introduced in the model. Finally, 14 specimens under oblique horizontal load were tested to verified the feasibility and applicability of the space truss-arch model. 展开更多
关键词 space truss-arch model rectangular frame column bilateral shear strength oblique horizontal load experimental research
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An Improved Functional Hierarchy Frame Model for System Maintainability
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作者 CHEN Dai Lin, CHEN Dong lin, WANG Ru gen, ZHU Xue ping College of Engineering, Air Force University of Engineering, Xi′an 710038, P.R.China 《International Journal of Plant Engineering and Management》 2003年第4期215-219,共5页
By means of analogy, this paper analyses the present functional hierarchyframe model for system maintainability, and presents an improved model. Practical applicationindicates that the improved model is visualized, mo... By means of analogy, this paper analyses the present functional hierarchyframe model for system maintainability, and presents an improved model. Practical applicationindicates that the improved model is visualized, more convenient and perfected over the perviousmodels. 展开更多
关键词 MAINTAINABILITY frame model index code maintenance code
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Cognitive Biases in Artificial Intelligence:Susceptibility of a Large Language Model to Framing Effect and Confirmation Bias
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作者 Li Hao Wang You Yang Xueling 《心理科学》 北大核心 2025年第4期892-906,共15页
The rapid advancement of Artificial Intelligence(AI)and Large Language Models(LLMs)has led to their increasing integration into various domains,from text generation and translation to question-answering.However,a crit... The rapid advancement of Artificial Intelligence(AI)and Large Language Models(LLMs)has led to their increasing integration into various domains,from text generation and translation to question-answering.However,a critical question remains:do these sophisticated models,much like humans,exhibit susceptibility to cognitive biases?Understanding the presence and nature of such biases in AI is paramount for assessing their reliability,enhancing their performance,and predicting their societal impact.This research specifically investigates the susceptibility of Google’s Gemini 1.5 Pro and DeepSeek,two prominent LLMs,to framing effects and confirmation bias.The study meticulously designed a series of experimental trials,systematically manipulating information proportions and presentation orders to evaluate these biases.In the framing effect experiment,a genetic testing decision-making scenario was constructed.The proportion of positive and negative information(e.g.,20%,50%,or 80%positive)and their presentation order were varied.The models’inclination towards undergoing genetic testing was recorded.For the confirmation bias experiment,two reports-one positive and one negative-about“RoboTaxi”autonomous vehicles were provided.The proportion of erroneous information within these reports(10%,30%,and 50%)and their presentation order were systematically altered,and the models’support for each report was assessed.The findings demonstrate that both Gemini 1.5 Pro and DeepSeek are susceptible to framing effects.In the genetic testing scenario,their decision-making was primarily influenced by the proportion of positive and negative information presented.When the proportion of positive information was higher,both models showed a greater inclination to recommend or proceed with genetic testing.Conversely,a higher proportion of negative information led to greater caution or a tendency not to recommend the testing.Importantly,the order in which this information was presented did not significantly influence their decisions in the framing effect scenarios.Regarding confirmation bias,the two models exhibited distinct behaviors.Gemini 1.5 Pro did not show an overall preference for either positive or negative reports.However,its judgments were significantly influenced by the order of information presentation,demonstrating a“recency effect,”meaning it tended to support the report presented later.The proportion of erroneous information within the reports had no significant impact on Gemini 1.5 Pro’s decisions.In contrast,DeepSeek exhibited an overall confirmation bias,showing a clear preference for positive reports.Similar to Gemini 1.5 Pro,DeepSeek’s decisions were also significantly affected by the order of information presentation,while the proportion of misinformation had no significant effect.These results reveal human-like cognitive vulnerabilities in advanced LLMs,highlighting critical challenges to their reliability and objectivity in decision-making processes.Gemini 1.5 Pro’s sensitivity to presentation order and DeepSeek’s general preference for positive information,coupled with its sensitivity to order,underscore the need for careful evaluation of potential cognitive biases during the development and application of AI.The study suggests that effective measures are necessary to mitigate these biases and prevent potential negative societal impacts.Future research should include a broader range of models for comparative analysis and explore more complex interactive scenarios to further understand and address these phenomena.The findings contribute significantly to understanding the limitations and capabilities of current AI systems,guiding their responsible development,and anticipating their potential societal implications. 展开更多
关键词 artificial intelligence large language models cognitive bias confirmation bias framing effect
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A MULTIPLE STRUCTURE RECONSTRUCTION ALGORITHM BASED ON WIRE FRAME MODEL
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作者 Du Jiangchuan Paul W.F. Poon 《Computer Aided Drafting,Design and Manufacturing》 1997年第1期36-44,共0页
A “LAG & RLC” visualization algorithm has been presented to display a clear three dimensional structure from stereo slice data which has the characteristics of multiple layer structure. This algorithm is based o... A “LAG & RLC” visualization algorithm has been presented to display a clear three dimensional structure from stereo slice data which has the characteristics of multiple layer structure. This algorithm is based on wire frame model which can do multiple logical operations and has multiple display effects. It has wide use in biomedical science and computer graphics. The practical system is based on PC with a TVGA adapter at least 512k byte display memory and 2M byte extended memory. 展开更多
关键词 LAG & RLC visualization three dimensional reconstruction wire frame model multiple structure
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Analyzing the mid-low porosity sandstone dry frame in central Sichuan based on effective medium theory 被引量:7
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作者 晏信飞 姚逢昌 +3 位作者 曹宏 巴晶 胡莲莲 杨志芳 《Applied Geophysics》 SCIE CSCD 2011年第3期163-170,239,共9页
Tight gas sandstone reservoirs in Guang'an are characterized by wide distribution and low abundance. Sandstone samples from this area usually have low porosity and poor connectivity. We analyze the observed velocity ... Tight gas sandstone reservoirs in Guang'an are characterized by wide distribution and low abundance. Sandstone samples from this area usually have low porosity and poor connectivity. We analyze the observed velocity data of tight sandstone samples with the Mori- Tanaka model, and give the sandstone framework physical model in this area based on theory and experiment analysis. The matrix modulus was obtained by an empirical relationship and then the experiment data were compared with the values predicted by the Mori-Tanaka model with different pore shapes. The results revealed that the experiment data were close to the model with low pore aspect ratio. Considering the matrix modulus and pore shape variation, we find that, under the condition of small mineral composition change, the effective pore aspect ratio of these samples increased with porosity evidently. 展开更多
关键词 tight sandstone dry frame Mori-Tanaka model pore aspect ratio INCLUSION
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基于N-K模型改进的FRAME建筑火灾风险评估 被引量:16
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作者 肖国清 黄仁和 陈春燕 《安全与环境学报》 CAS CSCD 北大核心 2022年第3期1139-1146,共8页
为了提高建筑火灾风险评估结果的准确性,降低建筑物火灾的危害性和事故损失程度,通过分析火灾事故原因,对FRAME模型中的评价指标体系进行改进和优化,探讨建筑消防安全管理水平对建筑物火灾风险、人员风险、建筑内活动风险的影响,并利用... 为了提高建筑火灾风险评估结果的准确性,降低建筑物火灾的危害性和事故损失程度,通过分析火灾事故原因,对FRAME模型中的评价指标体系进行改进和优化,探讨建筑消防安全管理水平对建筑物火灾风险、人员风险、建筑内活动风险的影响,并利用改进的FRAME模型评估堪培拉市某大楼的火灾风险。结果表明,采用N-K模型对指标体系中的风险因素进行耦合计算后,一级指标体系中四因素耦合风险为0.0507,大于其他耦合情况,验证了一级指标体系中增加建筑消防安全管理水平的准确性。堪培拉市该大楼的建筑物火灾风险由原来的2.11降低为1.12,人员风险由原来的6.56降低为4.24,建筑物内活动风险由原来的1.42降低为0.79,建筑物安全管理水平的增加会降低人员风险等级和建筑物内活动风险等级。 展开更多
关键词 安全工程 建筑火灾风险 N-K模型 frame 耦合分析
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“大学英语B”移动学习实证研究——基于FRAME模型的设计与开发 被引量:19
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作者 刘永权 《开放教育研究》 CSSCI 北大核心 2012年第3期76-82,共7页
随着信息技术的发展,移动学习越来越受到各级各类教育和培训机构的青睐。众多机构和院校纷纷设立项目开展研究,但这些研究要么尚局限于大学的普适技术实验室,要么在学校中被看作是课堂学习的补充,即使是在电大系统中也大多当作信息交流... 随着信息技术的发展,移动学习越来越受到各级各类教育和培训机构的青睐。众多机构和院校纷纷设立项目开展研究,但这些研究要么尚局限于大学的普适技术实验室,要么在学校中被看作是课堂学习的补充,即使是在电大系统中也大多当作信息交流和日常管理的平台。本研究以电大系统广泛采用的蓝卓校园网为平台,以北京广播电视大学五所分校的100名本科学生为研究对象,采用手机彩信(MMS)方式为试点学生发送教育部统考"大学英语B"微型课件。本研究以FRAME移动学习分析模型为出发点,在实验前期对学习对象、教学设计、内容呈现等方面做了充分调研。经过一个学期的试点后,从实验效果、学习者认可度和对下一步实验的意见、建议等方面实施了调查问卷和访谈。研究结果表明,与控制组学生相比,实验组学生考试通过率大幅度提升,绝大部分成人学习者对这种学习方式持欢迎态度,并对扩大试点范围和内容针对性等方面提出了建议。由于该研究是基于教学实践的实证研究,将对以后移动学习的普及乃至泛在学习的未来发展提供案例参考。 展开更多
关键词 “大学英语B” 移动学习 frame模型
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基于E-Model的语音帧分组传输性能研究 被引量:1
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作者 李腾 杨霄鹏 +1 位作者 杨朝阳 欧阳超 《测控技术》 CSCD 北大核心 2014年第5期35-39,共5页
voIP的语音帧分组大小是实时语音传输的关键参数。为提高网络效率和最大话路数,采用EModel的方法分析了RTP包中语音帧个数、语音长度、丢包概率和抖动缓冲区大小对语音质量的影响,给出了不同带宽时的最佳传输分组大小。仿真结果表明,在... voIP的语音帧分组大小是实时语音传输的关键参数。为提高网络效率和最大话路数,采用EModel的方法分析了RTP包中语音帧个数、语音长度、丢包概率和抖动缓冲区大小对语音质量的影响,给出了不同带宽时的最佳传输分组大小。仿真结果表明,在保证最基本的话音质量情况下,为不同链路确定合适的分组语音帧数能有效提高链路的最大话路数。 展开更多
关键词 VOIP E-model 语音帧 语音质量
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Composition of Model Interface--A Theorem of Model Composition
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作者 张亚东 刘宏超 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第3期61-68,共8页
Building a model for a object through model composition is a interesting topics, this paper research the interface composit ion of models in the Zeigler’s modeling methodology DEVS.
关键词 model composition model interface frame base order structure
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