期刊文献+
共找到1,416篇文章
< 1 2 71 >
每页显示 20 50 100
Influence factors on the seismic behavior and deformation modes of gravity retaining walls 被引量:2
1
作者 ZHU Hong-wei YAO Ling-kan LI Jing 《Journal of Mountain Science》 SCIE CSCD 2019年第1期168-178,共11页
This study investigated the influence factors on the seismic response and deformation modes of retaining walls using large-scale model shaking table tests. Experimental results showed that the distribution of peak sei... This study investigated the influence factors on the seismic response and deformation modes of retaining walls using large-scale model shaking table tests. Experimental results showed that the distribution of peak seismic earth pressures along the height of a wall was a single peak value curve. The seismic earth pressures on a gravel soil retaining wall were larger than the pressures on the weathered granite and quartz retaining walls. Also, the peak seismic earth pressure increased with increases in the peak ground acceleration and the wall height. The measured seismic active earth pressures on a rock foundation retaining wall were larger than the calculated values, and the action position of resultant seismic pressure was higher than 0.33 H. In the soil foundation retaining wall, the measured seismic earth pressures were much smaller than the calculated values, while the action position was slightly higher than 0.33 H. The soil foundation retaining wall suffered base sliding and overturning under earthquake conditions, while overturning was the main failure mode for the rock foundation retaining walls. 展开更多
关键词 GRAVITY retaining wall EARTHQUAKE action SEISMIC behavior Deformation mode SHAKING TABLE test
原文传递
Thermal behavior of an isolator with mode transition inducing back-pressure of a dual-mode scramjet 被引量:4
2
作者 Yang Qingchun Bao Wen +2 位作者 Chetehouna Khaled Zhang Silong Gascoin Nicolas 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第2期595-601,共7页
Combustion mode transition is a valuable and challenging research area in dual-mode scramjet engines.The thermal behavior of an isolator with mode transition inducing backpressure is investigated by direct-connect dua... Combustion mode transition is a valuable and challenging research area in dual-mode scramjet engines.The thermal behavior of an isolator with mode transition inducing backpressure is investigated by direct-connect dual-mode scramjet experiments and theoretical analysis.Combustion experiments are conducted under the incoming airflow conditions of total temperature1270 K and Mach 2.A small increment of the fuel equivalence ratio is scheduled to trigger mode transition.Correspondingly,the variation of the coolant flow rate is very small.Based on the measured wall pressures,the heat-transfer model can quantify the thermal state variation of the engine with active cooling.Compared with the combustor,mode transition has a greater effect on the isolator thermal behavior,and it significantly changes the isolator heat-flux and wall temperature.To further study the isolator thermal behavior from flight Mach 4 to Mach 7,a theoretical analysis is carried out.Around the critical point of combustion mode transition,sudden changes of the isolator flowfield and thermal state are discussed. 展开更多
关键词 Combustion mode Dual-mode scramjet ISOLATOR mode transition Thermal behavior
原文传递
Research on Behavior on Travel Mode, Going to Metro Station at Ho Chi Minh City
3
作者 Nguyen Van Duc Tran Van Duy Trinh Van Chinh 《Journal of Civil Engineering and Architecture》 2013年第1期120-124,共5页
This research presents an analysis of travel mode choice for trips to Ho Chi Minh City metro station. Research methods were inherited through a formula to calculate passenger traffic forecasts to predict passengers, g... This research presents an analysis of travel mode choice for trips to Ho Chi Minh City metro station. Research methods were inherited through a formula to calculate passenger traffic forecasts to predict passengers, going to the station. Based on the collected data of interviews, traffic surveys, and "Irwin & Von Cube" function, forecast the proportion of travel mode, and use to go to the station and leaving from the station. The results of study are used for the purpose of calculating the size of the metro station parking lots and parking layout plan. 展开更多
关键词 behavior on travel mode PARKING metro stations planning.
在线阅读 下载PDF
Modeling of Liquid Level and Bubble Behavior in Vacuum Chamber of RH Process 被引量:2
4
作者 Yi-hong LI Yan-ping BAO +3 位作者 Rui WANG Min WANG Qing-xue HUANG Yu-gui LI 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2016年第4期305-313,共9页
In the Ruhrstahl-Heraeus (RH) refining process, liquid steel flow pattern in a ladle is controlled by the fluid flow behavior in the vacuum chamber. Potassium chloride solution and NaOH solution saturated with CO2 w... In the Ruhrstahl-Heraeus (RH) refining process, liquid steel flow pattern in a ladle is controlled by the fluid flow behavior in the vacuum chamber. Potassium chloride solution and NaOH solution saturated with CO2 were respectively used as a tracer to investigate the liquid and gas flow behaviors in the vacuum chamber. Principal compo nent and comparative analysis were made to show the factors controlling mixing and circulation flow rate. The liquid level and bubble behavior in the vacuum chamber greatly affect fluid flow in RH process. Experiments were performed to investigate the effects of liquid steel level, gas flow rate, bubble residence time, and gas injection mode on mixing, decarburization, and void fraction. The results indicate that the mixing process can be divided into three regions: the flow rate affected zone, the concentration gradient-affected zone, and their combination. The liquid steel level in the vacuum chamber of 300 mm is a critical point in the decarburization transition. For liquid level lower than 300 mm, liquid steel circulation controls decarburization, while for liquid level higher than 300mm, bubble behavior is the main controlling factor. During the RH process, it is recommended to use the concentrated bubble injection mode for low gas flow rates and the uniform bubble injection mode for high gas flow rates. 展开更多
关键词 RH process liquid level vacuum chamber bubble behavior bubble residence time gas injection mode
原文传递
Reproductive Behaviors and Pairing Modes of Odontotermes fomosanus(Shiraki)Alates
5
作者 Ji Shilin Ji Baozhong +7 位作者 Liu Shuwen Cao Dandan Liu Jiajia Yang Jinjin Zhang Xinwei Zhao Zhengping Wang Liping Ehsan SOLEYMANINEJADIAN 《Plant Diseases and Pests》 CAS 2014年第6期1-7,24,共8页
[ Objectives ] To study the reproductive behaviors and the effect of different pairing modes on the developmental status of incipient colonies'of Odontote- rmes fomosanus (Shiraki). [ Methods ] We observed the repr... [ Objectives ] To study the reproductive behaviors and the effect of different pairing modes on the developmental status of incipient colonies'of Odontote- rmes fomosanus (Shiraki). [ Methods ] We observed the reproductive behaviors of male alates, female Mates and mated alates respectively. Male and female Mates had 9 pairing modes and founded 170 incipient colonies under laboratory conditions. The effect of pairing mode on incipient colonies' developmental status was ana- lyzed. [ Results ] Two peaking hours of mating activity within the daily circadian rhythm of Mate activity appeared from 09:00 to 10:00, and from 21:00 to 22:00, respectively. Courtship behavior before mating consisted of touching with antennae, connecting into a ring (head-to-end), and licking. The reproductive behavior ( calling, pairing, tandem, mating and oviposition) of nestmate pairs was different to that of non-nestmate pairs. The pairing time of non-nestmate pairs was signifi- candy longer than that of alates paired with siblings (P 〈 0.05 ). The non-swarming alates could mate with swarming or non-swarming Mates and lay fertile eggs which hatched successfully. However, the survival rate of colonies founded by non-swarming alates was very low. The death rate of incipient colonies was in the range of 0.61% -0. 99% after three months, while the death rate of the colonies founded by swarming alates was in the range of 0.22% -0.58%. Females that had been experimentally prevented from mating could lay eggs, but the eggs did not hatch. [ Conclusion] There are two distinct hourly peaks of mating activity within each 24 hour period. Incipient colonies founded by outbreeding have the highest probability of survival. 展开更多
关键词 Odontotermesfomosanus (Shiraki) Reproductive behavior 24-hour circadian rhythm Pairing modes Nest founded indoor
在线阅读 下载PDF
Activity Sequence Modes for Web Services and Verifications
6
作者 CHEN Bo YUAN Qingneng LIUZhiqi 《Wuhan University Journal of Natural Sciences》 CAS 2011年第6期500-506,共7页
Behavior requirement expression and its satisfiability verification for composite Web services is one of the ongoing issues in service computing. In this paper, the concept of behavior specifications based on activity... Behavior requirement expression and its satisfiability verification for composite Web services is one of the ongoing issues in service computing. In this paper, the concept of behavior specifications based on activity sequence is proposed to express one kind of behavioral requirements for composite Web services. Its basic element is activity sequence. The method to express such behavioral requirements by behavioral modes is presented. Five behavioral modes used in this method are adopted. Through map- ping modes to Labeled Transition Systems (LTSs), these modes are encoded with exact operation semantics. Then, the sufficient and necessary conditions as well as the checking algorithm for satisfiability of behavioral modes are given. Finally, an example analysis is presented. The result indicates that the behavioral requirements based on activity sequence are more suitable for the case of composite Web service than those based on activity or scenario. The behavioral modes expressions are concise and the satisfiability checking is effective by the given algorithm. 展开更多
关键词 Web service activity sequence behavior mode mode satisfiability
原文传递
Experimental Behavior of Partially Prestressed High Strength Concrete Beams 被引量:3
7
作者 Shady H. Salem Khalid M. Hilal +1 位作者 Tarek K. Hassan Ahmed S. Essawy 《Open Journal of Civil Engineering》 2013年第3期26-32,共7页
In the last few decades, prestressed concrete has been rapidly used in bridge engineering due to the enormous development in the construction techniques and the increasing need for long span bridges. High strength con... In the last few decades, prestressed concrete has been rapidly used in bridge engineering due to the enormous development in the construction techniques and the increasing need for long span bridges. High strength concrete has been also more widely spread than the past. It currently becomes more desirable as it has better mechanical properties and durability performance. Major defect of fully prestressed concrete is its low ductility;it may produce less alarming signs than ordinary reinforced concrete via smaller deflection and limited cracking. Therefore, partially prestressing is considered an intermediate design between the two extremes. So, combining high strength concrete with partial prestressing will result in a considerable development in the use of prestressed concrete structures regarding the economical and durability view points. This study presents the results of seven partially prestressed high strength concrete beams in flexure. The tested beams are used to investigate the influence of concrete compressive strength, prestressing steel ratio and flange width on the behavior of partially prestressed beams. The experimentally observed behaviors of all beams were presented in terms of the cracking load, ultimate load, deflection, cracking behavior and failure modes. 展开更多
关键词 PARTIALLY PRESTRESSED High Strength Concrete BEAMS SERVICEABILITY behavior Failure modes
在线阅读 下载PDF
Recognition of suspicious behavior using case-based reasoning 被引量:2
8
作者 夏利民 杨宝娟 涂宏斌 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第1期241-250,共10页
A novel method case-based reasoning was proposed for suspicious behavior recognition. The method is composed of three departs: human behavior decomposition, human behavior case representation and case-based reasoning.... A novel method case-based reasoning was proposed for suspicious behavior recognition. The method is composed of three departs: human behavior decomposition, human behavior case representation and case-based reasoning. The new approach was proposed to decompose behavior into sub-behaviors that are easier to recognize using a saliency-based visual attention model. New representation of behavior was introduced, in which the sub-behavior and the associated time characteristic of sub-behavior were used to represent behavior case. In the process of case-based reasoning, apart from considering the similarity of basic sub-behaviors,order factor was proposed to measure the similarity of a time order among the sub-behaviors and span factor was used to measure the similarity of duration time of each sub-behavior, which makes the similarity calculations more rational and comprehensive.Experimental results show the effectiveness of the proposed method in comparison with other related works and can run in real-time for the recognition of suspicious behaviors. 展开更多
关键词 visual attention mode case-based reasoning suspicious behavior order factor span factor
在线阅读 下载PDF
Container Networking Performance Analysis for Large-Scale User Behavior Simulation 被引量:1
9
作者 Yifang Ji Guomin Zhang +1 位作者 Shengxu Xie Xiulei Wang 《Journal of Computer and Communications》 2019年第10期136-146,共11页
Accurately simulating large-scale user behavior is important to improve the similarity between the cyber range and the real network environment. The Linux Container provides a method to simulate the behavior of large-... Accurately simulating large-scale user behavior is important to improve the similarity between the cyber range and the real network environment. The Linux Container provides a method to simulate the behavior of large-scale users under the constraints of limited physical resources. In a container-based virtualization environment, container networking is an important component. To evaluate the impact of different networking methods between the containers on the simulation performance, the typical container networking methods such as none, bridge, macvlan were analyzed, and the performance of different networking methods was evaluated according to the throughput and latency metrics. The experiments show that under the same physical resource constraints, the macvlan networking method has the best network performance, while the bridge method has the worst performance. This result provides a reference for selecting the appropriate networking method in the user behavior simulation process. 展开更多
关键词 Linux CONTAINER NETWORKING mode Network Performance USER behavior SIMULATION
在线阅读 下载PDF
夹层空间分布对多孔介质力学行为影响研究
10
作者 刘明鑫 杨永飞 +4 位作者 孙海 张磊 钟俊杰 张凯 姚军 《计算力学学报》 北大核心 2025年第5期811-818,共8页
在多孔介质形成过程中,颗粒的沉积和破碎等因素会导致不同结构的夹层,这些夹层显著影响多孔介质的力学行为。通过采用离散元方法,系统研究了夹层倾角和厚度对多孔介质力学行为的影响。结果表明,含夹层多孔介质的应力强度介于两种均质多... 在多孔介质形成过程中,颗粒的沉积和破碎等因素会导致不同结构的夹层,这些夹层显著影响多孔介质的力学行为。通过采用离散元方法,系统研究了夹层倾角和厚度对多孔介质力学行为的影响。结果表明,含夹层多孔介质的应力强度介于两种均质多孔介质之间,并随夹层倾角和厚度的变化而变化。粒间平均配位数在加载初期受夹层厚度影响显著,加载后期趋于稳定。配位数的变化影响了强弱力链的分布,夹层的倾角和厚度则决定了力链的应力传递大小和方向。此外,接触单元法向力和法向接触力随夹层倾角的增加而发生偏转,表现出显著的各向异性。本研究加深了对地层中含夹层多孔介质复杂力学行为的理解,为地质工程的优化和实际应用提供了有价值的参考。 展开更多
关键词 夹层 倾角和厚度 DEM 力学行为 接触模式
在线阅读 下载PDF
Fishbone Mode Excited by Deeply Trapped Energetic Beam Ions in EAST
11
作者 郑婷 吴斌 +10 位作者 徐立清 胡纯栋 臧庆 丁斯晔 李颖颖 伍兴权 王进芳 沈飙 钟国强 李昊 石同辉 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第6期595-600,共6页
This paper describes the fishbone mode phenomena during the injection of highpower neutral beams in EAST(Experimental Advanced Superconducting Tokamak).The features of the fishbone mode are presented.The change in f... This paper describes the fishbone mode phenomena during the injection of highpower neutral beams in EAST(Experimental Advanced Superconducting Tokamak).The features of the fishbone mode are presented.The change in frequency of the mode during a fishbone burst is from 1 kHz to 6 kHz.The nonlinear behavior of the fishbone mode is analyzed by using a prey-predator model,which is consistent with the experimental results.This model indicates that the periodic oscillations of the fishbone mode always occur near the critical value of fast ion beta.Furthermore,the neutral beam analysis for the discharge is done by using the NUBEAM module of the TRANSP code.According to the numerical simulation results and theoretical calculation,it can be concluded that the fishbone mode is driven by the deeply trapped energetic beam ions in EAST. 展开更多
关键词 EAST NBI fishbone mode TRANSP code nonlinear behavior
在线阅读 下载PDF
Edge Plasma behavior during Improved Confinement by Lower Hybrid Wave Heating in HT-6M Tokamak
12
作者 李建刚 鲍抑 +5 位作者 罗家融 万宝年 刘岳修 龚显祖 陈俊凌 梁云峰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2002年第5期1435-1444,共10页
Lower hybrid heating (LHH) has been successfully carried out in the HT-6M toka-mak. The H-mode has been obtained with a power threshold of 50 kW under a boronized wall condition. Both energy and particle confinements ... Lower hybrid heating (LHH) has been successfully carried out in the HT-6M toka-mak. The H-mode has been obtained with a power threshold of 50 kW under a boronized wall condition. Both energy and particle confinements have been improved along with a dropped edge plasma density and an increase electron temperature during the LHH phase. A negative Er well plays a key role of triggering and sustaining the good confinement. Both electrostatic fluctuation of the plasma potential and the density fluctuations dropped to an ultra-low level. The observation of an enhanced Er shear before the reduction in turbulence level is consistent with an increased Er shear as the cause of turbulence suppression. 展开更多
关键词 TOKAMAK lower hybrid wave heating H-mode edge plasma behavior
在线阅读 下载PDF
数字时代大学生阅读新样态、新问题与引导路径 被引量:1
13
作者 黄金艳 何春阳 《大学图书情报学刊》 2025年第3期25-30,38,共7页
网络技术的发展和智能设备的普及,使大学生的阅读呈现出阅读载体从纸版发展到屏幕、阅读符号从文字转变为图像、阅读空间从私人扩展到社会、阅读内容从深度裂变为碎片的新样态。数字时代的阅读在媒介技术的更迭与发展中变得更加便利,但... 网络技术的发展和智能设备的普及,使大学生的阅读呈现出阅读载体从纸版发展到屏幕、阅读符号从文字转变为图像、阅读空间从私人扩展到社会、阅读内容从深度裂变为碎片的新样态。数字时代的阅读在媒介技术的更迭与发展中变得更加便利,但同时也存在信息迷航现象、娱乐功利倾向、阅读视域窄化、沉溺浮躁情绪等隐忧。为此,应合理引导大学生走出信息迷航、打破茧房壁垒,强化价值引领、培养媒介素养,鼓励文字阅读、矫正娱乐功利,营造阅读氛围、回归深度阅读,改善数字时代大学生阅读状况。 展开更多
关键词 数字阅读 大学生 阅读行为 阅读模式 深阅读
在线阅读 下载PDF
行为改变轮理论视角下的高校翻转课堂模式优化研究
14
作者 张蓓佳 叶凤云 《合肥师范学院学报》 2025年第1期130-133,共4页
自引入翻转课堂以来,一直存在学生参与积极性不高的问题。文章以行为改变轮理论为分析框架,运用深度访谈及主题分析方法全面识别影响学生参与翻转课堂的影响因素,并将其映射至行为来源变量,再根据行为来源与干预功能间的对应关系,从硬... 自引入翻转课堂以来,一直存在学生参与积极性不高的问题。文章以行为改变轮理论为分析框架,运用深度访谈及主题分析方法全面识别影响学生参与翻转课堂的影响因素,并将其映射至行为来源变量,再根据行为来源与干预功能间的对应关系,从硬件环境、教师能力和学生品质三方面提出翻转课堂模式优化的具体路径。 展开更多
关键词 翻转课堂 行为改变轮 行为来源 模式优化
在线阅读 下载PDF
Modelling of Active and Latent Attributes Based on Traveler Perspectives: Case of Port City of Douala
15
作者 Anastasia Ojong Maayuk-Okpok Yin Ming 《World Journal of Engineering and Technology》 2023年第1期164-198,共35页
A growing stream of study stresses the relevance of subjective elements in understanding the hierarchy of preferences that underpin individual travel behavior. The purpose of this study is to evaluate the impact of va... A growing stream of study stresses the relevance of subjective elements in understanding the hierarchy of preferences that underpin individual travel behavior. The purpose of this study is to evaluate the impact of various factors on mode choice. To achieve this, a multinomial logit model (MNL) was used to analyze the relationships between mode choice and three classes of attributes;Combined Active and Latent, Active only and Latent only attributes. The data used are derived from surveys in the port city of Douala, Cameroon as a case study. Results stipulated that, the combined attributes model performed better than both active only attributes and latent only attributes models. Likewise, latent only attributes model performed better than active only attributes model. The advantage of modelling all three groups is for better selection of the most relevant attributes, and this is very relevant in understanding travel behavior of individuals and mode choice decisions. 展开更多
关键词 Multinomial logit model Latent Attributes mode Choice Individual behavior Active Attributes
在线阅读 下载PDF
Adaptive Proportional-Derivative Sliding Mode Control Law With Improved Transient Performance for Underactuated Overhead Crane Systems 被引量:8
16
作者 Menghua Zhang Xin Ma +4 位作者 Rui Song Xuewen Rong Guohui Tian Xincheng Tian Yibin Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第3期683-690,共8页
In this paper, an adaptive proportional-derivative sliding mode control(APD-SMC) law, is proposed for 2D underactuated overhead crane systems. The proposed controller has the advantages of simple structure, easy to im... In this paper, an adaptive proportional-derivative sliding mode control(APD-SMC) law, is proposed for 2D underactuated overhead crane systems. The proposed controller has the advantages of simple structure, easy to implement of PD control, strong robustness of SMC with respect to external disturbances and uncertain system parameters, and adaptation for unknown system dynamics associated with the feedforward parts. In the proposed APD-SMC law, the PD control part is used to stabilize the controlled system, the SMC part is used to compensate the external disturbances and system uncertainties,and the adaptive control part is utilized to estimate the unknown system parameters. The coupling behavior between the trolley movement and the payload swing is enhanced and, therefore, the transient performance of the proposed controller is improved.The Lyapunov techniques and the La Salle's invariance theorem are employed in to support the theoretical derivations. Experimental results are provided to validate the superior performance of the proposed control law. 展开更多
关键词 ADAPTABILITY adaptive proportional-derivative sliding mode control(APD-SMC) coupling behavior La Salle’s invariance theorem Lyapunov techniques robustness underactuated overhead crane
在线阅读 下载PDF
多腔中空薄壁方钢管混凝土短柱轴压性能研究
17
作者 张潇 龚俊 +2 位作者 邵永波 黄伟峰 李紫君 《重庆大学学报》 北大核心 2025年第2期86-101,共16页
为了提升中空夹层钢管混凝土(concrete-filled double-skin steel tubular,CFDST)短柱的轴压性能,提出并设计了薄壁方套方中空夹层多腔钢管混凝土(multi-cavity concrete-filled double-skin tubular,MCFDST)短柱,对其轴压力学性能进行... 为了提升中空夹层钢管混凝土(concrete-filled double-skin steel tubular,CFDST)短柱的轴压性能,提出并设计了薄壁方套方中空夹层多腔钢管混凝土(multi-cavity concrete-filled double-skin tubular,MCFDST)短柱,对其轴压力学性能进行了试验研究。试验试件包括15个方套方MCFDST短柱试件和3个方套方CFDST短柱试件。以混凝土抗压强度、外钢管宽厚比、空心率和是否设置拉肋为参数,通过分析试件的变形、荷载−位移曲线、破坏现象和延性系数,探究了各参数对试件的极限承载力、失效模式和延性的影响。试验结果显示:混凝土抗压强度从58 MPa提升至90 MPa,试件承载力提升46%,延性系数最高降低74%;外钢管宽厚比从39降低到29,试件承载力提升12.5%,延性系数明显增大;空心率从0.31增大到0.38,试件承载力提升了1.3%,延性系数仅提升1%;增设拉肋使构件承载力提升14.2%,延性系数最高提升282%。其次,利用试验数据验证了数值建模方法的有效性和模型的正确性,并开展了大量有限元参数分析,讨论了现行规范对该短柱轴压承载力的适用性,发现日本规范AIJ的预测公式可以精确估计MCFDST短柱轴压承载力。 展开更多
关键词 方套方中空夹层多腔钢管混凝土短柱 试验研究 轴压性能 失效模式 极限承载力 延性系数
在线阅读 下载PDF
基于SEM-ANN混合方法的用户对话式搜索行为影响因素研究
18
作者 潘文佳 茆汉国 孟勇 《图书馆工作与研究》 北大核心 2025年第11期35-45,96,共12页
文章基于UTAUT2模型,围绕绩效期望、努力期望、便利条件与价格价值4个变量构建用户对话式搜索行为影响因素模型。通过结构方程模型验证变量间的路径关系,并结合人工神经网络分析各变量的重要性。结果表明,4个变量均显著正向影响用户对... 文章基于UTAUT2模型,围绕绩效期望、努力期望、便利条件与价格价值4个变量构建用户对话式搜索行为影响因素模型。通过结构方程模型验证变量间的路径关系,并结合人工神经网络分析各变量的重要性。结果表明,4个变量均显著正向影响用户对话式搜索行为,且绩效期望和努力期望作为内部驱动因素对用户对话式搜索行为的影响最为显著,便利条件和价格价值作为外部驱动因素影响次之。ANN对自变量重要性的实证结果与SEM结论一致,进一步增强了SEM结论的可靠性。在此基础上,提出对话式搜索平台用户体验改善策略,即构建内容输出验证机制,强化用户技术效能信任;构建分层应用交互体系,减轻用户技术认知负担;构建智能嵌入式服务模式,增强用户技术使用便利性;实行梯度化定价策略,优化用户技术成本感知。 展开更多
关键词 对话式搜索 UTAUT2模型 搜索行为 神经网络 结构方程模型
原文传递
熔滴复合电弧增材制造中熔滴过渡模式对堆积层形貌的影响
19
作者 杜军 崔骜 +1 位作者 李志强 万志豪 《航空学报》 北大核心 2025年第17期325-335,共11页
在熔滴复合电弧增材制造中,连续可控的单分散熔滴流与倾斜钨极惰性气体(TIG)电弧熔池的交互作用决定了堆积层表面形貌、内部组织和制造缺陷等。为探明熔滴过渡模式对堆积层形貌的影响规律,基于计算流体力学(CFD)方法构建了熔滴复合电弧... 在熔滴复合电弧增材制造中,连续可控的单分散熔滴流与倾斜钨极惰性气体(TIG)电弧熔池的交互作用决定了堆积层表面形貌、内部组织和制造缺陷等。为探明熔滴过渡模式对堆积层形貌的影响规律,基于计算流体力学(CFD)方法构建了熔滴复合电弧增材制造过程三维瞬态熔池行为数值模型,与单道单层堆积成形实验结果相结合,比较性地分析了两种典型熔滴过渡模式下的熔滴冲击、聚并、铺展、凝固全过程。研究结果表明,当熔滴由低频大滴模式过渡至高频小滴模式时,熔滴与TIG电弧熔池的聚并行为由部分聚并转变为完全聚并,进而导致堆积层表面的“鱼鳞纹”结构特征明显减小。该研究对于进一步深入理解熔滴复合电弧增材制造机理、优化堆积工艺参数具有重要意义。 展开更多
关键词 熔滴复合电弧增材制造 熔池行为 熔滴过渡模式 聚并 堆积层表面形貌
原文传递
上一页 1 2 71 下一页 到第
使用帮助 返回顶部