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Research on Developing an Assessment Scale for Tourism Experience Elements of Ancient Shu Road Heritage Trail
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作者 Wang Yuan Wang Bo Zhou Jiang 《Contemporary Social Sciences》 2024年第5期118-142,共25页
Cultural ancient roads,known in Chinese as gudao,serve as heritage trails that carry historical exchanges across various regions in China.Due to their extensive preservation,wide geographical distribution,diverse them... Cultural ancient roads,known in Chinese as gudao,serve as heritage trails that carry historical exchanges across various regions in China.Due to their extensive preservation,wide geographical distribution,diverse thematic variations,and considerable tourist appeal,these paths have emerged as representative heritage trails,increasingly transforming into a novel tourism product experience that is highly favored by tourists and recognized by government authorities.However,research on ancient roads for tourism in China currently lacks a systematic theoretical framework,as well as relevant policies,regulations,and standards to guide their practical development.Therefore,there is a pressing need to draw upon international best practices and conduct foundational research to develop an experience element system that aligns with the perceptions,behaviors,and consumption characteristics of Chinese tourists,thereby advancing theoretical exploration in this field.This study focuses on the representative Ancient Shu Road as a case study and employs a mixed-method approach that integrates qualitative and quantitative research.It aims to construct a tourist-centric scale for the experience elements of ancient road tourism while analyzing the interactive relationship between these experience elements and tourist needs.This study addresses a significant gap in the development of indicator systems for domestic studies of ancient road tourism experiences.Ultimately,the study establishes a comprehensive scale that encompasses three core categories—trail resources and environment,facilities and services,and modes of tourism activities—along with eight primary dimensions:core resources,surrounding cultural environment,surrounding natural environment,tourism reception facilities and services,infrastructure and support services,information facilities and information services,and outdoor and recreational activities.This scale consists of thirty-two specific items,providing a robust reference for future research endeavors.Additionally,the study proposes specific development strategies related to key mechanisms,spatial configuration,and facility construction to enhance the overall development of ancient road tourism. 展开更多
关键词 ancient roads heritage trails tourism experience elements scale development
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EXPERIMENTAL STUDY ON UPGRADING OF A FINE-SCALED GRAPHITE ORE BY FLOTATION 被引量:1
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作者 余学斌 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2000年第2期53-57,共5页
Based on the quality and analysis of the medium carbon product whose grade was 81%-82%, the emphasis of the study was placed on the orthogonal experiments of roughing flotation reagent and single factors, such as abra... Based on the quality and analysis of the medium carbon product whose grade was 81%-82%, the emphasis of the study was placed on the orthogonal experiments of roughing flotation reagent and single factors, such as abrasive grain, pulp concentration and the rotating speed of flotation machine. The result with improvement in the grade of concentrate to 95% through the routine floatation method was achieved. 展开更多
关键词 fine-scaled GRAPHITE floatation orthogonal experiment
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The measuring method of early lateral energy fraction in the scale model experiments
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作者 NI Qiyu~1, FANG Yuan~2, WU Qixue~2, SUN Guangrong~2 (1. Yangzhou University, Yangzhou 225002, China 2. Institute of Acoustics, Nanjing University, Nanjing 210093,China) 《声学技术》 CSCD 2004年第S1期49-52,共4页
This paper introduces a measuring method of early lateral energy fraction in the scale model experiments. According to the interference principle of half wave length making the high frequency figure-8 directional micr... This paper introduces a measuring method of early lateral energy fraction in the scale model experiments. According to the interference principle of half wave length making the high frequency figure-8 directional microphone. With the signal-processing technique, a receiving and analyzing system, for the measurements of lateral energy fraction in the scale model is realized. 展开更多
关键词 ROOM ACOUSTICS scale model experiment EARLY LATERAL REFLECTIVE sound
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Adjoint Sensitivity Experiments of a Meso-β-scale Vortex in the Middle Reaches of the Yangtze River 被引量:3
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作者 王智 高坤 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2006年第2期267-281,共15页
A relatively independent and small-scale heavy rainfall event occurred to the south of a slow eastwardmoving meso-α-scale vortex. The analysis shows that a meso-β-scale system is heavily responsible for the intense ... A relatively independent and small-scale heavy rainfall event occurred to the south of a slow eastwardmoving meso-α-scale vortex. The analysis shows that a meso-β-scale system is heavily responsible for the intense precipitation. An attempt to simulate it met with some failures. In view of its small scale, short lifetime and relatively sparse observations at the initial time, an adjoint model was used to examine the sensitivity of the meso-β-scale vortex simulation with respect to initial conditions. The adjoint sensitivity indicates how small perturbations of initial model variables anywhere in the model domain can influence the central vorticity of the vortex. The largest sensitivity for both the wind and temperature perturbation is located below 700 hPa, especially at the low level. The largest sensitivity for the water vapor perturbation is located below 500 hPa, especially at the middle and low levels. The horizontal adjoint sensitivity for all variables is mainly located toward the upper reaches of the Yangtze River with respect to the simulated meso-β-scale system in Hunan and Jiangxi provinces with strong locality. The sensitivity shows that warm cyclonic perturbations in the upper reaches can have a great effect on the development of the meso-β-scale vortex. Based on adjoint sensitivity, forward sensitivity experiments were conducted to identify factors influencing the development of the meso-β-scale vortex and to explore ways of improving the prediction. A realistic prediction was achieved by using adjoint sensitivity to modify the initial conditions and implanting a warm cyclone at the initial time in the upper reaches of the river with respect to the meso-β-scale vortex, as is commonly done in tropical cyclone prediction. 展开更多
关键词 mei-yu front heavy rainfall meso-β-scale vortex adjoint method sensitivity experiment
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Analysis on nasal airway by using scale-adaptive simulation combined with standard κ-ω model and 3D printing modeling physical experiment 被引量:1
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作者 Jiemin Zhan Yangyang Xi +2 位作者 Kay Lin Weiguang Yu Wenqing Hu 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第4期215-219,I0006,共6页
The physiological structure of the upper respiratory tract is complex and varies with each individual,and the circulating air has turbulent performance.In this paper,based on computed tomography(CT)medical images publ... The physiological structure of the upper respiratory tract is complex and varies with each individual,and the circulating air has turbulent performance.In this paper,based on computed tomography(CT)medical images published online and the three-dimensional(3D)printing technology,a 3D model of the human upper respiratory tract was reconstructed and an experimental device of the upper respiratory tract was made.We implemented the respiratory experiment and measured the flow rate,and a scale-adaptive κ-ω model is applied for numerical simulation,the results are in good agreement.The flow field during respiratory was analyzed by coronal velocity cross section,vortex line and particle tracks.We found that the relatively strong shear effect happens at the areas of nasal valve and nasopharynx.In the middle and upper nasal tract,vortex line separation occurs and there is significant passage effect.The results indicate that SAS method is effective in studying upper respiratory airflow. 展开更多
关键词 3D PRINTER scale-adaptive SIMULATION Upper RESPIRATORY TRACT Physical experiment
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The idea and project of the “Medium-Scale Experiment Field for Earthquake Prediction”──Research on observations and applications of mining earthquake in Mentougou Coal Mine
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作者 张少泉 任振启 +2 位作者 张连城 张建军 邹立晔 《Acta Seismologica Sinica(English Edition)》 CSCD 1996年第4期142-146,148-150+152-,共10页
A brief account of the development of the research on mining earthquakes and the general situation of the Mentougou Coal Mine medium scale experiment field for earthquake prediction and the project of monitor and p... A brief account of the development of the research on mining earthquakes and the general situation of the Mentougou Coal Mine medium scale experiment field for earthquake prediction and the project of monitor and prediction is given. The differences of waveforms between mining earthquakes and natural earthquakes is discussed. The magnitude frequency distribution of the 79 000 mining earthquakes of over M L1.0 from 1984 to 1995 is summarized . Finally, taking PH and PV, the principal compressive stress components of the focal mechanism of the mining earthquakes, as the criteria, analyses the stress background of the 12 large mining earthquakes. 展开更多
关键词 mining earthquakes mining seismology earthquake prediction Mentougou Coal Mine medium scale experiment field for earthquake prediction.
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Small Scale Field Experiment on Breaking Wave Pressure on Vertical Breakwaters
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作者 Paolo Boccotti Vincenzo Fiamma +1 位作者 Giuseppe Barbaro Luigi Collia 《Open Journal of Marine Science》 2015年第4期412-421,共10页
A small scale field experiment (SSFE) was performed on vertical breakwaters in the surf zone. The following are some of the findings. Wind seas may yield breaking wave pressure notwithstanding some large deepwater wav... A small scale field experiment (SSFE) was performed on vertical breakwaters in the surf zone. The following are some of the findings. Wind seas may yield breaking wave pressure notwithstanding some large deepwater wave steepness, and small elevation of the wall above the mean water level. Caisson breakwaters can withstand some exceptionally high impulsive force peaks (even twice the weight in still water);whereas, with the same sea state and weight, a breakwater composed of layers of solid concrete blocks is destroyed. 展开更多
关键词 IMPULSIVE BREAKING Wave Pressure VERTICAL BREAKWATER Small scale Field experiment BREAKWATER FAILURE
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Bench and Full Scale Study of Removal Effect and Mutagenicity on Mesocyclops Leukarti with Chlorine Dioxide
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作者 左金龙 杨威 +1 位作者 刘亚男 林涛 《Journal of Donghua University(English Edition)》 EI CAS 2006年第4期88-93,共6页
Mesocyclops Leukarti of zooplankton propagates excessively in eutrophic water body and it can not be effectively inactivated by the conventional process in drinking waterworks for its special surface structure. In thi... Mesocyclops Leukarti of zooplankton propagates excessively in eutrophic water body and it can not be effectively inactivated by the conventional process in drinking waterworks for its special surface structure. In this paper, a study of removal efficiency on Mesocyclops Leukarti with chlorine dioxide in a drinking waterworks was performed. Bench scale results showed that chlorine dioxide is more effective against Mesocyclops Leukarti. And Mesocyclops Leukarti could be effectively removed from water by 1.0 mg/L chlorine dioxide preoxidation cooperated with the conventional process during the full scale study. The chlorite, by.product of prechiorine dioxide, was constant at 0.45 mg/L after filtration, which was lower than the critical value of the USEPA. GC-MS examination and Ames test showed that the quantity of organics and the mutngenicity in the water treated by chlorine dioxide is obviously less than that of prechlorination. 展开更多
关键词 bench scale study chlorine dioxide full scale study Mesocyclops Leukarti PREOXIDATION water treatment.
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Some results of modeling D-D seismogenic pattern by the fracture model experiment of large-scale rock samples(I) 被引量:2
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作者 陆阳泉 赵家骝 +2 位作者 钱家栋 王玉祥 刘建毅 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第2期95-102,共8页
sing the natural limestone samples taken from the field with dimension of 500 mm×500 mm×1 000 mm, the D-D (dilatancy-diffusion) seismogeny pattern was modeled under the condition of water injection, which ob... sing the natural limestone samples taken from the field with dimension of 500 mm×500 mm×1 000 mm, the D-D (dilatancy-diffusion) seismogeny pattern was modeled under the condition of water injection, which observes the time-space evolutionary features about the relative physics fields of the loaded samples from deformation, formation of microcracks to the occurrence of main rupture. The results of observed apparent resistivity show: ① The process of the deformation from microcrack to main rupture on the loaded rock sample could be characterized by the precursory spatial-temporal changes in the observation of apparent resistivity; ② The precursory temporal changes of observation in apparent resistivity could be divided into several stages, and its spatial distribution shows the difference in different parts of the rock sample; ③ Before the main rupture of the rock sample the obvious ″tendency anomaly′ and ′short-term anomaly″ were observed, and some of them could be likely considered as the ″impending earthquake ″anomaly precursor of apparent resistivity. The changes and distribution features of apparent resistivity show that they are intrinsically related to the dilatancy phenomenon of the loaded rock sample. Finally, this paper discusses the mechanism of resistivity change of loaded rock sample theoretically. 展开更多
关键词 fracture experiment of large-scale rock sample D-D seismogenic pattern apparent resistivity
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A Teaching Experiment in Modelling through Scale Reduction Methods: A Bridge to Later Trigonometric Methods
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作者 Toshikazu Ikeda Max Stephens Yuki Wada 《Journal of Mathematics and System Science》 2012年第6期359-367,共9页
In a teaching experiment, Japanese Grade 9 students investigated how to measure the height of an aerial balloon using different models involving angles and distances, and also to evaluate the models they developed. As... In a teaching experiment, Japanese Grade 9 students investigated how to measure the height of an aerial balloon using different models involving angles and distances, and also to evaluate the models they developed. As novices to mathematical modelling, they needed to decide which of several possible models were both valid and practicable, and the errors in measurement that are likely to arise. Opportunities to construct and use paper models, as scale reductions of the real situation, and discussing their results in small groups were effective in moving forward the thinking of many students on the dimensions mentioned above. While students were less able to identify different sources of errors, many came to appreciate the need to learn trigonometric techniques that are more suitable in dealing with problems of this kind. 展开更多
关键词 Teaching experiment scale reduction methods trigonometric methods validation and modification of the model spatialgeometrical thinking.
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Density disturbance of small-scale fieldaligned irregularities in the ionosphere heating experiments
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作者 Xiang WANG Chen ZHOU +2 位作者 Moran LIU Binbin NI Zhengyu ZHAO 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第12期9-18,共10页
A theoretical model which describes the small-scale irregularities excited by powerful high frequency (3–30 MHz) electromagnetic wave in ionosphere heating is investigated quantitatively in this paper. The model is... A theoretical model which describes the small-scale irregularities excited by powerful high frequency (3–30 MHz) electromagnetic wave in ionosphere heating is investigated quantitatively in this paper. The model is based on the transport equation in magnetic plasma and mode conversion from electromagnetic wave to electrostatic wave in ionospheric modification.Threshold electric field for exciting small-scale (meter scale) irregularities and spatial spectra of irregularities are analytically calculated by this model. The results indicate that background electron density and geomagnetic field play an important role for the threshold electric field and the spatial scale of the electron density irregularities. The results demonstrate that the electric field threshold increases with the decrease of the spatial scale of the irregularities. For exciting meter scale irregularities, the threshold electric field is about tens of mV m^(-1). The theoretical results are consistent with those of the experiments. 展开更多
关键词 small-scale irregularities ionosphere heating experiment thermal parametric instability resonant instability
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Analysis on River Bed Changes in Weir Downstream by Real-Scale Experiment
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作者 Dongwoo Ko Joongu Kang 《Engineering(科研)》 2018年第8期505-513,共9页
Flood damage has aggravated recently owing to artificial structures in high flow rare areas such as small rivers, which can lead to secondary damage. In this regard, studies are required to examine the conventional de... Flood damage has aggravated recently owing to artificial structures in high flow rare areas such as small rivers, which can lead to secondary damage. In this regard, studies are required to examine the conventional design criteria formulas to secure the stability of structures such as weirs and drop structures. Although studies on the stability of these structures have been conducted through small-scale experiments, few empirical studies have investigated the hydraulic phenomena occurring near actual artificial structures. In this study, we fabricated real-size models of weir and drop structure at the Andong River Experiment Center and investigated the flow patterns around the structures by applying the particle image velocimetry analysis technique with a flow tracker. We also measured the scour length in the waterspout section when the structures are overflowing, and compared it with the values calculated using the formula. Consequently, as the supply flow increases, the result is different from the value calculated using the formula given in the existing design standard, and it is judged to be inappropriate for a small stream area with high flow rate. Thus, it is necessary to consider the design factors such as energy gradient and the flow amount per unit width into weir and drop structure as well as the existing design factors in designing an apron section for a weir and drop structure. 展开更多
关键词 WEIR Drop Structure Real-scale experiment RIVER BED SCOUR Characteristic
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深层页岩压裂多级裂缝内支撑剂运移与分布规律 被引量:1
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作者 郭建春 唐堂 +4 位作者 张涛 周航宇 刘彧轩 李明峰 杨若愚 《天然气工业》 EI CAS CSCD 北大核心 2024年第7期1-11,共11页
深层页岩天然裂缝与层理缝发育,经体积改造后易形成“主缝+支缝+次微缝”的多级裂缝结构,但受高垂向应力和高水平应力差条件的影响,深层页岩压裂裂缝开度极窄且主次缝开度差异较大。为了明确多级裂缝内支撑剂运移机制与分布规律,搭建了... 深层页岩天然裂缝与层理缝发育,经体积改造后易形成“主缝+支缝+次微缝”的多级裂缝结构,但受高垂向应力和高水平应力差条件的影响,深层页岩压裂裂缝开度极窄且主次缝开度差异较大。为了明确多级裂缝内支撑剂运移机制与分布规律,搭建了大型可视化支撑剂输送实验系统,研究了泵注排量、液体黏度、支撑剂粒径、支撑剂浓度、裂缝特征参数对支撑剂运移与分布的影响规律,最后基于水电相似原理计算了裂缝整体导流能力并开展了评价分析。研究结果表明:①缝内支撑剂存在多种堆积模式,其形成由流体对支撑剂的携带能力决定;②支撑剂分流效率受多种因素影响,增大排量与减小支撑剂粒径均可提高分流效率;③多级裂缝内,增大排量与压裂液黏度均在一定程度上改善了支撑剂非均匀分布,但裂缝导流能力表现为先增大后减小;④综合支撑剂分流结果与多级裂缝内支撑剂分布规律,推荐坚持“大排量+低黏度”泵注思想,以保证大粒径支撑剂占比,适当混合小粒径支撑剂,构建“近井区高导流+远井区有支撑”的高导流裂缝体。结论认为,基于含多级裂缝的大型可视化支撑剂输送实验系统,全面系统研究了不同条件下多级裂缝内支撑剂运移与堆积的模式,研究成果可为深层页岩压裂泵注工艺参数设计与优化提供理论支撑。 展开更多
关键词 深层页岩 体积压裂 多级裂缝 水平裂缝 支撑剂运移 缝内分布 室内实验系统
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基于QoE理论的智慧医院平台可用性量表开发
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作者 贾培培 王潇伟 +4 位作者 李美华 陆连芳 冯娟 郎晗旭 魏丽丽 《中国医院管理》 北大核心 2024年第11期70-73,共4页
目的基于体验质量(Quality of Experience,QoE)理论构建智慧医院平台可用性量表,为智慧医院建设提供科学测量工具。方法采用文献回顾、焦点会议法、预调查对量表条目进行筛选、修订,形成正式量表。便利选取山东省8所智慧医院平台的1000... 目的基于体验质量(Quality of Experience,QoE)理论构建智慧医院平台可用性量表,为智慧医院建设提供科学测量工具。方法采用文献回顾、焦点会议法、预调查对量表条目进行筛选、修订,形成正式量表。便利选取山东省8所智慧医院平台的1000名用户进行调查,评价量表的信度和效度。结果智慧医院平台可用性量表包括6个维度24个条目。探索性因子提取出6个公因子:安全性、易用性、影响性、响应性、可靠性、灵活性。累计方差贡献率为64.045%,总体Cronbach’sα系数为0.941,6个维度的Cronbach’sα系数为0.782~0.963,重测信度为0.967。平均内容效度指数为0.972,条目水平内容效度指数为0.86~1.00。量表6个维度和系统可用性量表相关性系数为0.606~0.653,总体相关系数为0.647。结论基于QoE理论的智慧医院平台可用性量表具有较好的信度和效度,可作为用户对智慧医院平台体验情况的测量工具。 展开更多
关键词 体验质量 智慧医院平台 量表 信度 效度
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PEMFC空气系统流量和压力协同控制策略设计
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作者 王志红 王向光 颜伏伍 《太阳能学报》 EI CAS CSCD 北大核心 2024年第7期218-223,共6页
为提高质子交换膜燃料电池(PEMFC)空气系统的动态响应性能,避免局部缺气而导致其输出性能降低等问题的出现,针对空气系统存在流量和压力耦合的问题,分别采用PID、前馈解耦控制和模型预测控制(MPC)对空气系统进行控制,通过仿真和台架测试... 为提高质子交换膜燃料电池(PEMFC)空气系统的动态响应性能,避免局部缺气而导致其输出性能降低等问题的出现,针对空气系统存在流量和压力耦合的问题,分别采用PID、前馈解耦控制和模型预测控制(MPC)对空气系统进行控制,通过仿真和台架测试,验证控制算法的有效性。结果表明,两种控制算法相比较PID均具有较好的控制效果,空气流量和空气压力均能快速跟随设定值,PEMFC发动机的输出性能平稳。 展开更多
关键词 质子交换膜燃料电池 空气供应系统 解耦控制 台架试验
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长期模拟失重实验中医证候诊断量表的研究
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作者 石宏志 徐冲 +9 位作者 许家佗 范全春 刘军莲 屠立平 胡晓娟 张成普 赵爽 米涛 李勇枝 李莹辉 《航天医学与医学工程》 CAS 2024年第1期8-14,共7页
目的制订适用于长期模拟失重实验受试者整体健康状态评价的中医证候诊断量表,并对其信度与效度进行初步评价。方法本研究基于对长期航天飞行不同阶段中的人体中医病机的认识,通过文献调研结合专家咨询的方法制订量表。采用重测信度和内... 目的制订适用于长期模拟失重实验受试者整体健康状态评价的中医证候诊断量表,并对其信度与效度进行初步评价。方法本研究基于对长期航天飞行不同阶段中的人体中医病机的认识,通过文献调研结合专家咨询的方法制订量表。采用重测信度和内部一致性系数来检验量表信度;进行为期90 d的头低位卧床实验,采用项目分析和因子分析法评价量表的效度,采用旋转成分矩阵分析各条目与维度间的相关性。结果长期模拟失重实验中医证候诊断量表包含8个维度、57个条目。信度分析结果:30名受试者前后两次量表评分总分相关系数为0.889,表明量表的稳定性很高;量表的克龙巴赫α系数为0.934,表明量表内部一致性非常好;分半信度校正后为0.858,表明量表的信度很高。效度分析结果:57个条目在高分组和低分组的差异均有统计学意义(P<0.01),各条目与量表总分的皮尔逊相关系数均>0.4(P<0.001);采用主成分因子分析法提取8个公因子,累积贡献率为55.293%;旋转成分矩阵分析结果经医理分析和专家反馈显示,与初始8个维度的重合度高达87.5%,表明量表的结构效度良好。结论量表具有良好的信度和效度,能够进行中医证候诊断,适用于长期模拟失重实验,可为受试者主观感受的评价提供客观量化新方法。 展开更多
关键词 长期模拟失重实验 中医 证候 诊断 量表
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钢管输电塔挂线节点足尺模型失效模式与承载力提升分析
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作者 翟彬 李素超 +3 位作者 张丽娟 徐再根 王志远 毛晨曦 《地震研究》 CSCD 北大核心 2024年第1期1-9,共9页
针对特高压钢管输电塔挂线位置节点在极端荷载下的安全性,提出了挂线节点双侧挂线板协同受力的构造改进措施,并对比研究两种挂线节点的极限承载力与失效模式。通过足尺挂线节点处的承载力试验与有限元分析,比较挂线节点在单侧板受力、... 针对特高压钢管输电塔挂线位置节点在极端荷载下的安全性,提出了挂线节点双侧挂线板协同受力的构造改进措施,并对比研究两种挂线节点的极限承载力与失效模式。通过足尺挂线节点处的承载力试验与有限元分析,比较挂线节点在单侧板受力、双侧板受力情况下的应力分布与承载能力,分析传力螺母与挂线板之间的合理初始间距。结果表明:双侧受力时两侧挂线板均发生弯曲破坏,受力形式更加合理,节点板应力分布更加均匀,挂线点的屈服承载力可以提升一倍以上,传力螺母与挂线板之间的合理初始间隙为2~4 mm。 展开更多
关键词 特高压输电塔 挂线节点 承载力 足尺试验 有限元模拟 传力螺母
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基于缩尺模型试验的船舶沉浮系统压载特性研究
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作者 万新斌 于姝雯 +1 位作者 李胜博 杨卫英 《舰船科学技术》 北大核心 2024年第11期1-5,共5页
船舶沉浮系统通过重力浸水、压载泵注水等不同方式完成预压载、快速压载等不同压载过程,进而调整船舶姿态,以满足快速沉浮的任务要求。建立精确的沉浮系统管网仿真模型是分析船舶压排载特性与优化沉浮系统管网设计的基础。然而,复杂的... 船舶沉浮系统通过重力浸水、压载泵注水等不同方式完成预压载、快速压载等不同压载过程,进而调整船舶姿态,以满足快速沉浮的任务要求。建立精确的沉浮系统管网仿真模型是分析船舶压排载特性与优化沉浮系统管网设计的基础。然而,复杂的管网流路以及部件的非线性阻力特性均给管网仿真模型的精度带来了巨大挑战。本文首先采用缩尺模型试验结果,修正管网仿真模型中的关键部件阻力特性参数,使得管网模型仿真精度达到95.7%以上。基于修正后的沉浮系统管网模型,研究了预压载与快速压载顺序执行以及联合执行2种方案的船舶压载特性,其中联合压载时间相较于顺序压载过程缩短了26.75 min,为沉浮和姿态平衡系统的设计和控制策略的优化提供重要参考。 展开更多
关键词 模型试验 沉浮系统 模型修正 压载特性
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贯穿实验过程的电路实验考核评价方法
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作者 陈灵敏 陈安 +2 位作者 曾思明 杜宇上 杨汝 《实验室科学》 2024年第5期164-170,共7页
线上线下协同的多时间尺度实践教学是提高学生实践能动性和工程创新能力的有效措施。基于电路实验线上线下协同多维度、多时间尺度的实验教学内容和多空间、多时间尺度的教学模式,以学生实践能力和综合素质培养为目标,合理设计贯穿每个... 线上线下协同的多时间尺度实践教学是提高学生实践能动性和工程创新能力的有效措施。基于电路实验线上线下协同多维度、多时间尺度的实验教学内容和多空间、多时间尺度的教学模式,以学生实践能力和综合素质培养为目标,合理设计贯穿每个实验过程的多维度实验考核评价内容,提炼每个实验项目的课前-课中-课后的考核评价指标和量化各项指标的梯度权重,提出贯穿实验过程的电路实验考核评价方法,全面、科学地评价学生该门课程的综合成绩。该考核评价方法推动了电路实验教学的改革,提高了教与学的质量和效率,培养了学生的创新能力。 展开更多
关键词 实验过程 电路实验考核 创新能力 多时间尺度
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延长油田低渗油藏分层注水缓蚀阻垢剂的制备及性能研究
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作者 李军 杜科宇 +1 位作者 任春燕 吴利超 《化学工程师》 CAS 2024年第7期41-45,共5页
本文以丙烯酸(AA)、顺丁烯二酸钠(MAH-Na)、乙烯吡咯烷酮(NVP)及自合成的季铵化咪唑啉(QIM)为单体,采用偶二异丁眯盐酸盐(V50)紫外光引发体系合成了四元共聚缓蚀阻垢剂。通过正交实验筛选出最佳单体配比为18∶6∶3.5∶2.5,结合静态结垢... 本文以丙烯酸(AA)、顺丁烯二酸钠(MAH-Na)、乙烯吡咯烷酮(NVP)及自合成的季铵化咪唑啉(QIM)为单体,采用偶二异丁眯盐酸盐(V50)紫外光引发体系合成了四元共聚缓蚀阻垢剂。通过正交实验筛选出最佳单体配比为18∶6∶3.5∶2.5,结合静态结垢实验、动态腐蚀实验以及分子量测试得出最佳合成条件为:V50加量为0.6wt%、反应时间为8h、单体浓度为35wt%,此最佳条件合成的缓蚀阻垢剂的缓蚀率达86.1%,CaCO_(3)阻垢率达91.2%,CaSO_(4)阻垢率达96.1%,BaSO_(4)阻垢率达73.2%,各项性能优于市场采购的单一功能缓蚀剂与阻垢剂。 展开更多
关键词 四元共聚 单体配比 正交实验 缓蚀阻垢剂
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