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The Rise of Islamic Values in Media: A Three Dimensions Analysis of Film Industry in Indonesia
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作者 Muhamad Fadhil Nurdin Fitaha Aini +1 位作者 Vina E ffendi Mohamad Saleeh Bin Rahamad 《Journalism and Mass Communication》 2016年第8期455-468,共14页
This article focuses on the rise of Islamic values in media with concern to the film industry in Indonesia. In this nation, 88.22% of 254 million of the population are Muslims. However, this substantial quantity is bu... This article focuses on the rise of Islamic values in media with concern to the film industry in Indonesia. In this nation, 88.22% of 254 million of the population are Muslims. However, this substantial quantity is burden some if Muslims have a lack of appreciation to history and are intellectually weak. In addition, cultural degradation due to the rapid changes in information & communication technology diminishes moral and ethics of society. The growth of film industry in the Soeharto era which curb freedom of expression and media resulted in films which were more oriented to comedy, horror, and vulgar. The aims of this study specifically are: (1) to identify the film industry (macro) in the context of challenge of Indonesian Muslim in social and culture; (2) to analyze the political interests of film production company owner (meso) in his films; (3) to conduct textual analysis (micro) of two films which include Islamic values in the dialogues. Two films, Nagabonar Jadi 2 (Nagabonar Become 2) and Alangkah Lucunya Negeri lni (How Funny This Country ls), were selected as samples for their contents that fearlessly criticize corrupt governance and promote integrity and good deeds. The three dimensions of critical discourse which was proposed by Norman Fairlough (1992) was used to evaluate the local film industry from the perspective of macro, meso, and micro. The macro-analysis found that Indonesian films act should be modified to keep up with modernized and recent trends in media and film industry. The meso analysis showed that competition between film companies are very though, however, film quality determines the popularity of the company in public. According to the company owner's agenda, Deddy Mizwar determines the quality of films produced, instead of quantity, as apriority. Thus, in post-reform era, the freedom of expression which enforced by the Act No. 9 of 1998, the company start producing Islamic films. Deddy Mizwar concerns for society are not only through the media but also political. He recently elected as the deputy governor of West Java province with the full support of an Islamic Party (Partai Keadilan Sejahtera). The textual studies have found similarities of the Islamic values in the content of the two films which are tawaqal (trust and reliance on God) and Taqwa, the pursuit of knowledge, respecting for the elderly, and belief in the Hereafter. 展开更多
关键词 film studies Islamic values macro analysis meso analysis miso analysis Indonesia
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A Study on the Impact of PEST Analysis on the Pharmaceutical Sector: The Bangladesh Context
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作者 Mohammad Nayeem Abdullah Robaka Shamsher 《Journal of Modern Accounting and Auditing》 2011年第12期1446-1456,共11页
PEST (Political, Economic, Social, and Technological) analysis of any industry sector investigates the important factors that are affecting the industry and influencing the companies operating in that sector. The pu... PEST (Political, Economic, Social, and Technological) analysis of any industry sector investigates the important factors that are affecting the industry and influencing the companies operating in that sector. The purpose of this study is to analyze the pharmaceutical sector of Bangladesh using the framework of PEST. This report brings to light the current state of the sector its progress and its problems. Through this study the researchers try to discuss the affect of various macro-economic factors of political, economic, social, and technological aspect on the industry and its related problems and prospects for the future. 展开更多
关键词 PEST analysis pharmaceutical sector industry and macro economic factors
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Static inelastic analysis of RC shear walls
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作者 陈勤 钱稼茹 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2002年第1期94-99,共6页
A macro-model of a reinforced concrete (RC) shear wall is developed for static inelastic analysis.The model is composed of RC column elements and RC membrane elements.The column elements are used to model the boundary... A macro-model of a reinforced concrete (RC) shear wall is developed for static inelastic analysis.The model is composed of RC column elements and RC membrane elements.The column elements are used to model the boundary zone and the membrane elements are used to model the wall panel.Various types of constitutive relationships of concrete could be adopted for the two kinds of elements.To perform analysis,the wall is divided into layers along its height.Two adjacent layers are connected with a rigid beam.There are only three unknown displacement components for each layer.A method called single degree of freedom compensation is adopted to solve the peak value of the capacity curve.The post-peak stage analysis is performed using a forced iteration approach.The macro-model developed in the study and the complete process analysis methodology are verified by the experimental and static inelastic analytical results of four RC shear wall specimens. 展开更多
关键词 RC shear wall macro-model static inelastic analysis EXPERIMENT
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EVOLUTION FILTRATION PROBLEMS WITH SEAWATER INTRUSION: TWO-PHASE FLOW DUAL MIXED VARIATIONAL ANALYSIS 被引量:1
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作者 Gonzalo ALDUNCIN 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1142-1162,共21页
Tow-phase flow mixed variational formulations of evolution filtration problems with seawater intrusion are analyzed. A dual mixed fractional flow velocity-pressure model is considered with an air-fresh water and a fre... Tow-phase flow mixed variational formulations of evolution filtration problems with seawater intrusion are analyzed. A dual mixed fractional flow velocity-pressure model is considered with an air-fresh water and a fresh water-seawater characterization. For analysis and computational purposes, spatial decompositions based on nonoverlapping multidomains, above and below the sea level, are variationally introduced with internal boundary fluxes dualized as weak transmission constraints. Further, parallel augmented and exactly penalized duality algorithms, and proximation semi-implicit time marching schemes, are established and analyzed. 展开更多
关键词 two-phase flow in coastal aquifers fractional two-phase flow dual mixed variational analysis macro-hybrid variational formulations augmented exactly penalized duality algorithms proximation semi-implicit time marching schemes
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Genre Analysis of English Abstracts in petroleum Articles
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作者 孙萍 《海外英语》 2010年第6X期139-140,142,共3页
Abstract:This article endeavors to investigate the difference and similarities between English abstracts in the field of petroleum written by native academicians and Chinese scholars by means of comparison.It is resea... Abstract:This article endeavors to investigate the difference and similarities between English abstracts in the field of petroleum written by native academicians and Chinese scholars by means of comparison.It is researched from two aspects:macro-genre structure and micro-linguistic features based on corpus study in order to find out the reason why some articles are good enough to be employed in the international research organization such as EI or SCI,and propose constructive instructions for informative abstract writing. 展开更多
关键词 GENRE analysis ABSTRACT macro-genre structure micro-linguistic features
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吊索猝断下钢桁拱桥的时变体系抗连续倒塌性能
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作者 王晓明 杨文杰 +3 位作者 邹杰 邓华 高泽亮 张浩楠 《工程力学》 北大核心 2026年第2期209-222,共14页
吊索猝断下在役钢桁拱桥体系的抗连续倒塌性能为结构应对非对称极端作用提供了必要的内部缓冲机制,材料劣化会改变体系抗连续倒塌过程中的再平衡格局。基于等效卸载的AP法模拟吊索猝断下应力波的传递与叠加效应,建立了吊索猝断下体系时... 吊索猝断下在役钢桁拱桥体系的抗连续倒塌性能为结构应对非对称极端作用提供了必要的内部缓冲机制,材料劣化会改变体系抗连续倒塌过程中的再平衡格局。基于等效卸载的AP法模拟吊索猝断下应力波的传递与叠加效应,建立了吊索猝断下体系时变连续倒塌易损性评估方法。基于MATLAB/OpenSEES编制了单元纤维的时变演化参数组管理程序,建立了基于纤维宏单元的时变体系连续倒塌数值模拟方法,并通过动力试验数据验证了数值模拟的准确性;采用增量动力分析(IDA)法,开展了吊索猝断下钢桁拱桥的连续倒塌易损性分析,研究了材料劣化对吊索猝断下体系抗连续倒塌性能的影响规律。结果表明:吊索猝断会引起钢桁拱桥主要承载构件响应增大,其中猝断吊索相邻范围内受影响最大;材料劣化会降低钢桁拱桥体系的抗连续倒塌能力;基于IDA法的时变连续倒塌模型,可有效评估钢桁拱桥服役年限内的抗连续倒塌性能。 展开更多
关键词 钢桁拱桥 连续倒塌 纤维宏单元 易损性 IDA法
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Unveiling first self-healing in metallised film capacitor:A macro-micro analysis
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作者 Yushuang He Feipeng Wang +6 位作者 Guoqiang Du Lei Pan Jian Li Hongming Yang Xiao Zhang Zhicheng Zhang Kaizheng Wang 《High Voltage》 2025年第2期362-373,共12页
Metallised film capacitors(MFCs)are renowned for their unique self-healing(SH)properties,which bestow them with exceptional reliability and stability in the face of intense electric fields,high voltages,and pulse powe... Metallised film capacitors(MFCs)are renowned for their unique self-healing(SH)properties,which bestow them with exceptional reliability and stability in the face of intense electric fields,high voltages,and pulse power applications.Nonetheless,the exploration of SH characteristics concerning single-layer dielectric film remains insufficient for advancing MFC reliability evaluation.To establish the theoretical correlation of SH characteristics from the device to the film in the MFCs,this work developed a simulation model to analyse the SH dynamic behaviour in the MFCs.The effects of coupling capacitors,arc resistance and insulation resistance on the macroscopic characteristics(voltage drop and pulse current)are focused during the SH process in MFCs.The results indicate that SH is primarily associated with the voltage drop duration rather than the sampling current.Consequently,the SH process in MFC is characterised as an abrupt decrease in voltage to its minimum value.This refinement enhances the SH energy dissipation model of MFC.The quantified relationship between the macroscopic characteristics and microstructure evolution(polypropylene decomposition and aluminium electrode vaporisation)is established in MFCs under diverse SH energy levels.As SH energy and duration increase,the proportion of energy attributed to polypropylene decomposition increases,resulting in multi-layer ablation and adhesion within the metallised film and a pronounced deterioration in MFC electrical performance.The examination of macro-micro perspectives sheds new light on the intricate mechanisms governing the SH behaviour in MFCs,offering valuable insights for the advancement of their design,reliability evaluation,and performance optimisation in diverse electrical applications. 展开更多
关键词 pulse current reliability evaluation polypropylene decomposition aluminium electrode vaporisation voltage drop metallised film capacitors macro micro analysis metallised film capacitors mfcs
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Turbulence,aeration and bubble features of air-water flows in macro-and intermediate roughness conditions 被引量:2
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作者 Stefano PAGLIARA Thendiyath ROSHNI Iacopo CARNACINA 《Water Science and Engineering》 EI CAS 2011年第2期170-184,共15页
Free surface flows aeration potential causing the in macro- and intermediate flow characteristics to vary roughness conditions have a high with slopes and discharges. The underlying mechanism of two-phase flow charact... Free surface flows aeration potential causing the in macro- and intermediate flow characteristics to vary roughness conditions have a high with slopes and discharges. The underlying mechanism of two-phase flow characteristics in macro- and intermediate roughness conditions were analyzed in an experimental setup assembled at the Laboratory of Hydraulic Protection of the Territory (PITLAB) of the University of Pisa, Italy. Crushed angular rocks and hemispherical boulders were used to intensify the roughness of the bed. Flow rates per unit width ranging between 0.03 m^2/s and 0.09 m^2/s and slopes between 0.26 and 0.46 were tested over different arrangements of a rough bed. Analyses were mainly carried out in the inner flow region, which consists of both bubbly and intermediate flow regions. The findings revealed that the two-phase flow properties over the rough bed were much affected by rough bed arrangements. Turbulence features of two-phase flows over the rough bed were compared with those of the stepped chute data under similar flow conditions. Overall, the results highlight the flow features in the inner layers of the two-phase flow, showing that the maximum turbulence intensity decreases with the relative submergence, while the bubble frequency distribution is affected by the rough bed elements. 展开更多
关键词 turbulent flow aeration characteristics BOULDER macro- and intermediate roughness correlation analysis two-phase flow
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Three-Dimensional Nonlinear Dynamic Model and Macro Control of Real Estate
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作者 Dan Ma Shengwu Zhou Haojin Lv 《Intelligent Information Management》 2010年第5期325-328,共4页
In this paper, according to economics of real estate and macro-control theory, combine with the characteristics of the real estate market, macro-control of the real estate market is studied. After giving the dynamic m... In this paper, according to economics of real estate and macro-control theory, combine with the characteristics of the real estate market, macro-control of the real estate market is studied. After giving the dynamic model of three-dimensional nonlinear differential equations based on the total number of houses on the real estate business, the government’s averages housing investment funds and the standard price, systematically established the stability conditions of equilibrium point for this model. What’s more, through the use of extreme value analysis model, government funds have been invested in real estate business building devotion principles and the construction base of the real estate businessmen has also been estimated successfully. This provides the corresponding theoretical basis for government macro control policy-making. 展开更多
关键词 REAL ESTATE macro Control THREE-DIMENSIONAL Dynamic Model EXTREME Value analysis
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The Concept of MDSA (Macro Demand Spatial Approach) on Spatial Demand Forecasting for Main Development Area in Transmission Planning
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作者 Djoko Darwanto Sudarmono Sasmono Ngapuli Irmea Sinisuka Mukmin Widyanto Atmopawiro 《Journal of Energy and Power Engineering》 2014年第6期1124-1131,共8页
MDSA (macro demand spatial approach) is an approach introduced in long time electricity demand forecasting considering location. It will be used at transmission planning and policy decision on electricity infrastruc... MDSA (macro demand spatial approach) is an approach introduced in long time electricity demand forecasting considering location. It will be used at transmission planning and policy decision on electricity infrastructure development in a region. In the model, MDSA combined with PCA (principal component analysis) and QA (qualitative analysis) to determine main development area in region and the variables that affecting electricity demand in there. Main development area is an area with industrial domination as a driver of economic growth. The electricity demand driver variables are different for type of electricity consumer. However, they will be equal for main development areas. The variables which have no significant effect can be reduced by using PCA. The generated models tested to assess whether it still at the range of confidence level of electricity demand forecasting. At the case study, generated model for main development areas at South Sumatra Subsystem as a part of Sumatra Interconnection System is still in the range of confidence level. Thus, MDSA can be proposed as alternative approach in transmission planning that considering location. 展开更多
关键词 Electricity demand forecasting macro demand spatial approach principal component analysis qualitative analysis maindevelopment area transmission planning.
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我国科研论文国内外发表状况与比较分析——以工程与材料科学、社会科学宏观主题为例
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作者 卢军霞 陈振英 《高等工程教育研究》 北大核心 2025年第1期122-126,共5页
本文通过统计2012-2023年期间,分析和比较国内工程与材料科学、社会科学领域研究人员在国内外发表科研论文的状况,研判我国科研论文在国外发表的现状以及趋势。借助Citation Topics基于论文引用的分类算法,以及论文间相互引用关系,将相... 本文通过统计2012-2023年期间,分析和比较国内工程与材料科学、社会科学领域研究人员在国内外发表科研论文的状况,研判我国科研论文在国外发表的现状以及趋势。借助Citation Topics基于论文引用的分类算法,以及论文间相互引用关系,将相关文献汇聚形成离散文献集群,从工程与材料科学、社会科学两个领域近12年的总论文数量、高质量研究论文占比,分析了国内科研论文在国外发表的趋势,并比较了国内发表状况。从数量上看,国内研究人员选择将科研论文在国外发表的趋势还在持续增加,国外发表的科研论文增幅是国内发表的增幅的两倍,且绝对数量相差悬殊;尤其是社科领域的科研论文,在国外发表占比超过98%。同时,从质量上分析,2015年以来,高质量科研论文在国外发表的增势出现了缓解和回落迹象,与国家持续出台重要政策时间可能关联,可佐证政策的有效导向。 展开更多
关键词 科研论文 国外发表 宏观主题 比较分析
原文传递
基于非房室模型的药代动力学参数计算SAS宏工具
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作者 张莉 娄冬华 《中国临床药理学与治疗学》 北大核心 2025年第5期608-621,共14页
目的:通过开发SAS宏工具,以适用于不同给药方式和给药频率的非房室模型分析(NCA)药代动力学(PK)参数计算。方法:结合非房室模型分析PK参数计算原理,设计SAS宏程序结构并编制SAS宏程序,结合模拟实例演示宏程序的用法。结果:本研究基于非... 目的:通过开发SAS宏工具,以适用于不同给药方式和给药频率的非房室模型分析(NCA)药代动力学(PK)参数计算。方法:结合非房室模型分析PK参数计算原理,设计SAS宏程序结构并编制SAS宏程序,结合模拟实例演示宏程序的用法。结果:本研究基于非房室模型分析,通过SAS宏语言编程,实现单次和稳态完整PK参数的计算,并且支持血管外、静脉输注和静脉注射3种给药方式以及4种曲线下面积(AUC)算法。该方法通过与权威计算软件比较,在各种计算场景下的结果均高度一致,且首次可测量浓度之前的观测时间(Tlag)的计算结果更为准确。结论:%M_CREATE_PK_PARAMETERS宏是支持NCA PK完整参数计算的SAS宏,为PK参数的计算提供了一种准确、高效、灵活的解决方案,具备广泛的应用前景。 展开更多
关键词 非房室模型分析(NCA) SAS宏 PK参数
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跨尺度微纳米三坐标测量机研制及误差分析
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作者 黄强先 刘慧洁 +4 位作者 张祖杨 李红莉 程荣俊 张连生 李瑞君 《光学精密工程》 北大核心 2025年第19期3058-3069,共12页
为解决三维超精密测量中大行程运动与高精度测量之间的矛盾,研制了一种新型的跨尺度微纳米三坐标测量机(Cross-Scale Micro-Nano Coordinate Measuring Machine,CSMN-CMM),测量体积为100 mm×100 mm×100 mm。不同于传统坐标测... 为解决三维超精密测量中大行程运动与高精度测量之间的矛盾,研制了一种新型的跨尺度微纳米三坐标测量机(Cross-Scale Micro-Nano Coordinate Measuring Machine,CSMN-CMM),测量体积为100 mm×100 mm×100 mm。不同于传统坐标测量机的结构形式,CSMN-CMM采用独立的、三维方向都符合阿贝原则的计量系统布局,既消除了运动系统对计量系统的影响,又避免阿贝误差。其运动系统由三维气浮宏动台和六自由度微动台构成,宏微协同的运动模式在提高测量效率的同时完成高精度触发及测量任务。测头系统方面,采用高精度三维接触式测头或谐振式触发测头完成测量,谐振式触发测头的光纤探针测球直径可达70μm以下。针对测量机存在的主要误差来源,基于坐标转换建立空间误差补偿模型并完成误差分离。依据ISO 10360-2,对CSMN-CMM整机测量性能进行检验,得到其最大允许误差优于±(250 nm+3.6×10^(-6)×L)。实验结果表明,CSMN-CMM具有亚微米三维测量精度,可以实现低至100μm内尺寸的测量,其结构设计及关键技术对高精度三维测量具有重要意义。 展开更多
关键词 微纳米测量机 无阿贝误差 宏微运动系统 精密测量 误差分析
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现代能源化工过程涉氢环境中金属氢脆研究的多尺度现状分析与展望
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作者 蒋小霞 李营 +4 位作者 尤佳乐 张涛 刘浩伟 李永红 白红存 《洁净煤技术》 北大核心 2025年第12期125-141,共17页
氢脆是现代化工和能源加工过程中涉氢环境下的关键材料失效问题,其复杂性横跨从原子行为到宏观断裂的多尺度耦合过程,直接影响氢能基础设施和化工设备的安全性与服役寿命。然而,目前尚缺乏针对金属材料氢脆的系统多尺度现状分析与展望... 氢脆是现代化工和能源加工过程中涉氢环境下的关键材料失效问题,其复杂性横跨从原子行为到宏观断裂的多尺度耦合过程,直接影响氢能基础设施和化工设备的安全性与服役寿命。然而,目前尚缺乏针对金属材料氢脆的系统多尺度现状分析与展望。借助多尺度研究思想,系统梳理并分析了金属材料中氢脆现象及其作用机制的相关研究,提出未来研究方向与展望。在宏观尺度层面,重点探讨了掺氢比、温度、湿度及外加载荷等服役参数对氢脆敏感性的协同作用规律,揭示这些外部因素如何通过非线性耦合方式调控材料的氢脆失效行为。在介观尺度上,深入揭示了晶粒尺寸、晶界类型及相界面特性对氢扩散与聚集行为的调控机制,阐明不同介观结构特征如何影响氢的局域富集与裂纹萌生路径。在微观尺度上,系统解析了氢原子与位错、晶界、孪晶界及纳米析出物等晶格缺陷的交互作用机制,阐明氢在缺陷处的俘获、迁移与富集行为及其对材料脆化的原子级起源。进一步提出了微观原子–介观晶界–宏观裂纹的多尺度耦合研究方法。通过跨尺度关联揭示多场共同作用下金属材料氢致失效的链式传递机制,构建从氢原子局域富集到介观结构演化再到宏观裂纹扩展的完整失效图景。基于上述多尺度现状分析与展望,可为现代化工和能源加工过程涉氢环境中抗氢脆材料的设计与优化,以及氢能工程的安全评估与寿命预测提供重要的理论依据和科学参考。 展开更多
关键词 氢能 氢脆 多尺度分析 宏观结构 介观结构 微观结构 氢安全
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排水沥青路面抗滑性能衰变室内模拟研究 被引量:1
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作者 官志桃 何兆益 +3 位作者 黄昭东 郭剑辉 张权 刘奕 《武汉大学学报(工学版)》 北大核心 2025年第6期903-912,共10页
采用小型4轮加速加载试验装置,根据传统抗滑性能测试方法并结合激光轮廓测量技术探究了不同级配排水沥青混合料的抗滑性能衰变规律,通过统计软件(statistical package for social sciences,SPSS)和分析软件(data processing system,DPS... 采用小型4轮加速加载试验装置,根据传统抗滑性能测试方法并结合激光轮廓测量技术探究了不同级配排水沥青混合料的抗滑性能衰变规律,通过统计软件(statistical package for social sciences,SPSS)和分析软件(data processing system,DPS)对其抗滑性能与宏观纹理指标的相关性进行了分析研究,并构建了多指标抗滑回归模型。结果表明:级配对抗滑性能影响很大;在标准轴载作用下,摆值与平均构造深度在加速加载作用下的衰减幅度与衰减速度存在差异,但均满足Asymptotic指数模型;根据抗滑性能与宏观纹理指标平均断面深度、轮廓算术平均波长、偏度等3个指标可建立显著的多元二次多项式回归模型。 展开更多
关键词 排水沥青路面 抗滑性能 衰变特性 宏观纹理 回归分析
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废弃全钢胎颗粒热解过程中质量和形态变化研究
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作者 王树宇 薛志亮 +4 位作者 朱静 付鑫 周永刚 胡一鸣 黄群星 《化工学报》 北大核心 2025年第7期3459-3467,F0002,共10页
热解是废轮胎高值资源化利用的重要途径,研究废轮胎颗粒热解过程中质量及形态变化对于优化设计热解反应装置具有重要意义。基于自行搭建设计的光学图像分析可视化热解实验装置,开展了不同温度下轮胎颗粒热解过程中的质量及形态变化实验... 热解是废轮胎高值资源化利用的重要途径,研究废轮胎颗粒热解过程中质量及形态变化对于优化设计热解反应装置具有重要意义。基于自行搭建设计的光学图像分析可视化热解实验装置,开展了不同温度下轮胎颗粒热解过程中的质量及形态变化实验。研究结果表明,反应温度对热解反应速率具有显著影响。当温度从400℃升高至600℃时,最大热解反应速率提高了约1.9倍。此外,轮胎颗粒在热解过程中经历了先膨胀、再开裂、后塌缩的动态变化过程,开裂阶段伴随着质量的快速下降。同时,热解温度对膨胀倍率和失重速率峰值出现的时间间隔具有显著影响。 展开更多
关键词 废物处理 轮胎颗粒 污染 热解 失重 光学图像分析 形态变化
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滇西T_(2)h砂化白云岩空间分布特征及宏微观形成机理研究
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作者 龚欣月 董家兴 +4 位作者 刘文连 许汉华 眭素刚 槐以高 金克盛 《工程地质学报》 北大核心 2025年第4期1354-1365,共12页
砂化白云岩具有岩体结构破碎,强度低等特殊的物理力学特性,不同地层岩性、不同地质构造背景下的砂化白云岩,其地质特性及形成机理存在差异。为揭示滇西三叠系河湾街组(T_(2)h)的砂化白云岩的宏微观形成机理,本文分析总结了研究区内砂化... 砂化白云岩具有岩体结构破碎,强度低等特殊的物理力学特性,不同地层岩性、不同地质构造背景下的砂化白云岩,其地质特性及形成机理存在差异。为揭示滇西三叠系河湾街组(T_(2)h)的砂化白云岩的宏微观形成机理,本文分析总结了研究区内砂化白云岩的空间分布特征,同时选取了不同砂化等级的砂化白云岩岩样进行电镜扫描和能谱分析试验,探讨分析其宏微观形成机理。研究结果表明:(1)滇西T_(2)h砂化白云岩在空间分布上呈现垂直分带性,在构造应力的作用下形成裂隙和结构面,为溶蚀作用提供了条件;(2)根据电镜扫描试验,分析得到砂化白云岩的微观溶蚀机理为:沿晶体表面和裂隙溶蚀-晶体崩解脱落-溶孔和溶缝不断扩大,同时可说明滇西T_(2)h砂化白云岩在微观形成机理方面是溶蚀作用占主导;(3)通过化学成分分析得到,在微砂化到剧烈砂化白云岩的演化过程中,Mg元素不断在迁移,且流失速度较快。 展开更多
关键词 砂化白云岩 宏微观形成机理 扫描电镜 能谱分析 岩石微观结构
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面向数控加工仿真的数控指令统一解析及匹配方法
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作者 梁彬 丁国富 +2 位作者 魏俊 李瑞 江磊 《机床与液压》 北大核心 2025年第13期39-46,共8页
数控指令解析作为数控加工仿真过程的关键步骤之一,直接影响数控加工仿真系统的兼容性、准确性、灵活性等性能指标。由于数控指令种类繁多、格式互异,常见的解析方法难以保证对变化参数、数学运算以及逻辑运算的准确解析,同时也难以将... 数控指令解析作为数控加工仿真过程的关键步骤之一,直接影响数控加工仿真系统的兼容性、准确性、灵活性等性能指标。由于数控指令种类繁多、格式互异,常见的解析方法难以保证对变化参数、数学运算以及逻辑运算的准确解析,同时也难以将数控指令匹配到仿真宏指令。为此,提出数控指令统一解析及匹配方法。首先,基于数控指令特性,建立可拓展的词法、功能、语法及匹配规则;然后,通过将规则作用于解析过程的方式,设计可拓展的指令和参数解析算法,并实现了对包含数学和逻辑运算的数控指令解析;再基于匹配规则将解析后所形成的指令集和参数集匹配到仿真宏指令,形成可执行的仿真宏指令流。最后,在VC++平台上开发数控指令解析模块,通过加工仿真验证了该方法的有效性和兼容性。 展开更多
关键词 数控指令解析 数控加工仿真 数控系统 仿真宏指令 匹配方法
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全球蓝莓贸易趋势与市场动态分析
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作者 冯奕煊 李亚男 +2 位作者 王颖 李金英 吴林 《中国果树》 2025年第7期124-130,共7页
通过对2013—2022年全球蓝莓产业贸易数据进行详细分析,揭示其在国际市场上的贸易动态和发展趋势。运用描述性统计分析方法,结合FAO、联合国商品贸易统计数据库以及美国农业市场服务局(AMS)网站等权威机构提供的长期贸易和价格数据,描... 通过对2013—2022年全球蓝莓产业贸易数据进行详细分析,揭示其在国际市场上的贸易动态和发展趋势。运用描述性统计分析方法,结合FAO、联合国商品贸易统计数据库以及美国农业市场服务局(AMS)网站等权威机构提供的长期贸易和价格数据,描述全球蓝莓贸易的总体趋势,包括进口量与进口额、出口量与出口额的增长情况;分析主要蓝莓出口国的国际市场占有率和贸易竞争力指数,以评估各国在蓝莓国际贸易中的地位和表现;探讨蓝莓价格的动态变化及其背后原因,包括季节性供需变化、有机与非有机产品之间的价格差异等。研究结果对了解全球蓝莓产业贸易现状、预测未来市场趋势以及为政策制定者提供决策支持具有重要意义。 展开更多
关键词 贸易 市场分析 宏观环境 机遇与挑战
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基于新型侧板加强型组合节点宏观模型的框架抗震性能
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作者 熊清清 周筱淋 +2 位作者 张旺 吴文博 刘奥华 《科学技术与工程》 北大核心 2025年第16期6879-6889,共11页
为实现对新型侧板加强型连接组合节点的高效分析,提出梁-柱-板组合节点宏观力学模型,确定楼板与钢梁连接的最优实现方法,验证了组合节点宏观模型的准确性和可靠性。建立6层3跨的传统侧板加强型梁柱连接节点框架模型(TSP)、新型侧板加强... 为实现对新型侧板加强型连接组合节点的高效分析,提出梁-柱-板组合节点宏观力学模型,确定楼板与钢梁连接的最优实现方法,验证了组合节点宏观模型的准确性和可靠性。建立6层3跨的传统侧板加强型梁柱连接节点框架模型(TSP)、新型侧板加强型梁柱连接节点框架模型(FBSP)和新型侧板加强型梁柱连接组合节点框架模型(CJ-FBSP),对3种考虑实际节点性能的框架模型开展了弹塑性时程分析,获得不同框架模型在地震波作用下的顶点位移时程曲线、层间位移角、塑性耗能及塑性铰分布等。结果表明:根据所提的弹簧刚度计算方法,可以很好地模拟TSP和FBSP裸钢梁节点的性能;同时,考虑栓钉剪切滑移和抗拔性能的连接方法,可准确地模拟组合节点的受力性能;3种节点框架模型的层间位移角均未超过规范限值(1/50);FBSP框架模型的最大层间位移角小于TSP框架模型但大于CJ-FBSP框架模型,且塑性耗能能力最强;CJ-FBSP框架由于有楼板的加强作用,塑性铰出铰率最小,塑性耗能能力较弱。 展开更多
关键词 新型侧板加强型连接组合节点 宏观力学模型 层间位移角 弹塑性时程分析
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