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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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基于宏微观摩擦接触模型的湿式摩擦元件温度场失效概率分析
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作者 吴健鹏 丁奥 +3 位作者 马彪 李和言 王立勇 杨成冰 《中国机械工程》 北大核心 2026年第1期40-50,59,共12页
为精确量化湿式摩擦元件的温度场失效概率问题,先建立热-机械耦合仿真与单对粗糙峰接触模型实时交互的宏微观摩擦模型获取温度,再构建温度场失效概率统计模型。利用核密度估计建立失效参数的概率密度函数,采用蒙特卡罗模拟进行了概率计... 为精确量化湿式摩擦元件的温度场失效概率问题,先建立热-机械耦合仿真与单对粗糙峰接触模型实时交互的宏微观摩擦模型获取温度,再构建温度场失效概率统计模型。利用核密度估计建立失效参数的概率密度函数,采用蒙特卡罗模拟进行了概率计算。试验结果表明,仿真与试验的数据高度吻合,所建立的统计模型能有效且精确计算湿式摩擦元件的失效概率。 展开更多
关键词 湿式摩擦副 失效概率分析 宏微观交互 核密度函数 蒙特卡罗模拟
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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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煤炭行业“十五五”发展展望
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作者 朱拴成 杜立科 +3 位作者 秦容军 郭建利 李丽英 袁俊林 《煤炭经济研究》 2026年第1期6-11,共6页
系统回顾了“十四五”期间煤炭行业在产量增长、进口提升、消费攀升及经济效益波动等方面的发展情况,分析了“十五五”时期煤炭行业面临的宏观经济放缓、人口结构变化、生态环境约束、信息技术革新以及新能源加速替代等多重宏观环境变... 系统回顾了“十四五”期间煤炭行业在产量增长、进口提升、消费攀升及经济效益波动等方面的发展情况,分析了“十五五”时期煤炭行业面临的宏观经济放缓、人口结构变化、生态环境约束、信息技术革新以及新能源加速替代等多重宏观环境变革。研究指出,“十五五”期间煤炭行业将进入深刻转型阶段,呈现兜底保障作用突出、供应西移特点进一步凸显、消费达峰趋势明显、清洁低碳利用成为发展重点等趋势特点。面对当前供大于求、企业普遍亏损的现状,建议行业建立供给侧响应机制、构建以成本为核心的生产体系,推动煤炭行业在保障能源安全的同时实现高质量转型。 展开更多
关键词 煤炭行业 “十五五”趋势特点 宏观环境分析
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宏微运动平台导轨架模态分析及优化设计
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作者 张璐凡 姜薄士 +1 位作者 张鹏启 张相锋 《机械设计与制造》 北大核心 2026年第2期97-100,106,共5页
导轨架作为超高加速度宏微运动平台的关键机构,导轨架的共振会严重影响平台的定位精度。这里通过SolidWorks和ANSYS Workbench联合仿真,对导轨架进行研究分析,首先在SolidWorks中建立模型并使模型参数化,导入到ANSYS Workbench中进行模... 导轨架作为超高加速度宏微运动平台的关键机构,导轨架的共振会严重影响平台的定位精度。这里通过SolidWorks和ANSYS Workbench联合仿真,对导轨架进行研究分析,首先在SolidWorks中建立模型并使模型参数化,导入到ANSYS Workbench中进行模态分析,获得导轨架的前六阶固有频率和振型,然后利用ANSYS Workbench的DM模块,设计质量最轻和一阶固有频率最大的优化目标,对模型进行直接优化和响应面优化。最后,将得到的优化方案进行对比分析,结果表明,导轨架一阶固有频率增加了4.0%,质量减少了4.55%。通过对导轨架进行优化设计,达到了指定优化目标,研究结果对宏微运动平台超精密定位实现具有重要意义。 展开更多
关键词 宏微运动平台 导轨架 模态分析 优化设计
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短纤纱力学性能的宏细观耦合分析与数值模拟
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作者 赵泽文 吕宽 +1 位作者 苏旭中 孙丰鑫 《纺织学报》 北大核心 2026年第1期106-114,共9页
环锭短纤纱的力学柔性与强度主要源于其独特的交缠捻曲结构和纤维丛微尺度效应与细观力学的耦合,但当前其力学性能研究仍主要基于宏观唯象表征或定性分析阶段。为阐明低应力下的短纤纱细观结构对其宏观力学性能的影响规律并简化模拟计... 环锭短纤纱的力学柔性与强度主要源于其独特的交缠捻曲结构和纤维丛微尺度效应与细观力学的耦合,但当前其力学性能研究仍主要基于宏观唯象表征或定性分析阶段。为阐明低应力下的短纤纱细观结构对其宏观力学性能的影响规律并简化模拟计算复杂度,构建了等效模型纱线系统,从纤维尺度效应、成纱纤维取向及纱线捻度3个维度开展有限元模拟分析与实验验证。结果表明:短纤纱拉伸断裂强度与其捻度、纤维搭接长度呈非线性正相关,且捻度和搭接长度对短纤纱断裂失效模式转变存在逾渗阈值;纤维取向角与纱线力学强度呈准线性负相关。该研究结果有利于揭示短纤纱的力学宏细观关联规律与力学强度机制,可为纱线超结构设计和力学性能调控提供理论参考。 展开更多
关键词 短纤纱 数值模拟 纱线力学性能 细观结构 宏细观关联规律 有限元分析
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基于PEST方法的我国船舶制造业外部宏观环境分析
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作者 刘慧菊 刘飞飞 +4 位作者 韩涛 易海霞 饶靖 董亮 黄敏健 《造船技术》 2026年第1期87-92,共6页
基于政治、经济、社会和技术分析(Political,Economic,Social,and Technological Analysis,PEST)方法,从政治因素、经济因素、社会因素和技术因素等4个维度研究我国船舶制造业智能化改造和数字化转型的外部宏观环境。研究表明,政策红利... 基于政治、经济、社会和技术分析(Political,Economic,Social,and Technological Analysis,PEST)方法,从政治因素、经济因素、社会因素和技术因素等4个维度研究我国船舶制造业智能化改造和数字化转型的外部宏观环境。研究表明,政策红利释放、市场需求升级、社会基础夯实和技术创新突破共同构成我国船舶制造业智能化改造和数字化转型的多维动力机制。研究结果可为相关部门制定产业政策和船舶制造业实施智能化改造和数字化转型提供理论参考。 展开更多
关键词 船舶制造业 外部宏观环境 PEST 船舶企业 智能化改造 数字化转型
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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
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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:2
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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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