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文明1(civilized)、文明2(civilization)、文明3(civitas)——论“文明”一词的三种不同含义
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作者 叶文宪 《许昌学院学报》 CAS 2024年第3期57-65,共9页
学术界对于“什么是文明”存有争议的原因,是把文明(civilized)、文明社会(civilization)和国家(civitas)三个不同的概念混为一谈造成的。“文明1”大致相当于英语civilized(文明的)。文化是人群的生活方式,但是不仅彬彬有礼、琴棋书画... 学术界对于“什么是文明”存有争议的原因,是把文明(civilized)、文明社会(civilization)和国家(civitas)三个不同的概念混为一谈造成的。“文明1”大致相当于英语civilized(文明的)。文化是人群的生活方式,但是不仅彬彬有礼、琴棋书画、轻歌曼舞、美味佳肴是文化,愚昧粗鲁、恶俗陋习、野风蛮舞、吃糠咽菜也是生活方式,所以文明1不完全等同于文化,而只有被认可与受推崇的文化才被称为文明。无论古今中外,作为文化的文明1都是褒义的,文明1即“文明”的本义,也是对文化的价值判断。“文明2”相当于英语civilization(文明社会),摩尔根用以指称继蒙昧社会与野蛮社会之后出现的、高于蒙昧与野蛮状态的社会阶段。作为社会形态的文明2当然比蒙昧与野蛮社会要进步,但是文明社会并非一切都是文明的,其中充斥着种种不文明的蒙昧与野蛮,所以不能说文明2就是“文明的”社会。“文明3”相当于英语civitas(国家),是中国学者根据恩格斯的“国家是文明社会的概括”得出的概念,系指继部落联盟或酋邦之后出现的社会组织形态。因为不同国家的国体与政体各不相同,有了国家之后并非一切都变得比野蛮社会更文明了,所以作为国家的文明3也不都是“文明的”国家。 展开更多
关键词 文明1(civilized) 文明2(civilization) 文明3(civitas)
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Civil3d技术在河道治理中的应用分析
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作者 范会平 《中文科技期刊数据库(文摘版)工程技术》 2024年第3期0114-0116,共3页
为了切实加强水环境保护及水资源管理与利用,近年来我国一直在加快和加大力度落实河道治理,要想保证河道治理达到预期效果,并最大程度提高河道治理工程生态效益,首先要确保河道治理设计与施工方案的科学合理性,可见借助现代化技术手段,... 为了切实加强水环境保护及水资源管理与利用,近年来我国一直在加快和加大力度落实河道治理,要想保证河道治理达到预期效果,并最大程度提高河道治理工程生态效益,首先要确保河道治理设计与施工方案的科学合理性,可见借助现代化技术手段,优化和改进河道治理设计与规划是很有必要的。基于此本文首先进行Civil3d技术的梳理与说明,继而详细分析Civil3D软件在某河道治理项目的具体应用,旨在与相关工作人员相互交流、共同探讨。 展开更多
关键词 civil3d技术 河道治理 技术应用
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MTTSNet:Military time-sensitive targets stealth network via real-time mask generation
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作者 Siyu Wang Xiaogang Yang +4 位作者 Ruitao Lu Zhengjie Zhu Fangjia Lian Qing-ge Li Jiwei Fan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期601-612,共12页
The automatic stealth task of military time-sensitive targets plays a crucial role in maintaining national military security and mastering battlefield dynamics in military applications.We propose a novel Military Time... The automatic stealth task of military time-sensitive targets plays a crucial role in maintaining national military security and mastering battlefield dynamics in military applications.We propose a novel Military Time-sensitive Targets Stealth Network via Real-time Mask Generation(MTTSNet).According to our knowledge,this is the first technology to automatically remove military targets in real-time from videos.The critical steps of MTTSNet are as follows:First,we designed a real-time mask generation network based on the encoder-decoder framework,combined with the domain expansion structure,to effectively extract mask images.Specifically,the ASPP structure in the encoder could achieve advanced semantic feature fusion.The decoder stacked high-dimensional information with low-dimensional information to obtain an effective mask layer.Subsequently,the domain expansion module guided the adaptive expansion of mask images.Second,a context adversarial generation network based on gated convolution was constructed to achieve background restoration of mask positions in the original image.In addition,our method worked in an end-to-end manner.A particular semantic segmentation dataset for military time-sensitive targets has been constructed,called the Military Time-sensitive Target Masking Dataset(MTMD).The MTMD dataset experiment successfully demonstrated that this method could create a mask that completely occludes the target and that the target could be hidden in real time using this mask.We demonstrated the concealment performance of our proposed method by comparing it to a number of well-known and highly optimized baselines. 展开更多
关键词 Deep learning military application Targets stealth network Mask generation Generative adversarial network
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Effect of dietary supplementation with discardednutrient medium of Cordyceps militaris on layingperformance and diversity of intestinal flora in
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作者 XU Fangxu ZHANG Jinying +2 位作者 LI Bingxin LIU Yefei WANG Ze 《沈阳师范大学学报(自然科学版)》 CAS 2024年第2期186-192,共7页
The aim of the experiment was to explore the feasibility of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 100 g/kg, 200 g/kg, 300 g/kg of discarded nutrient medium of Cordy... The aim of the experiment was to explore the feasibility of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 100 g/kg, 200 g/kg, 300 g/kg of discarded nutrient medium of Cordyceps militaris were added to the basal diet of laying hens. The results showed that the optimal addition of discarded nutrient medium of Cordyceps militaris in the diet of laying hens was 10%. According to the results of measuring the conventional indicators of eggs, the weight of eggs produced by laying hens fed with discarded nutrient medium of Cordyceps militaris was higher than that of laying hens fed with ordinary laying hens. The content of interleukin^(-1)(IL-1) in the experimental group was significantly higher than that in the control group, and the concentration of IL-1 increased by 141.5 pg/mL, which indicated that the application of discarded nutrient medium of Cordyceps militaris effectively improved the immunity of laying hens. The high-throughput analysis of the intestinal contents of the two groups of laying hens showed that the microbial population abundance of the intestinal tract of the experimental group was greater than that of control group, and the application of discarded nutrient medium of Cordyceps militaris increased the diversity of bacteria in the intestinal tract of laying hens. In addition, the sensitivity of some pathogenic bacteria in the intestinal tract of chickens to drugs was also increased, thereby reducing the use of antibiotics. The secondary utilization of discarded nutrient medium of Cordyceps militaris has great development and utilization prospects, which provided a scientific reference and basic theoretical basis for the development of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 展开更多
关键词 Cordyceps militaris discarded nutrient medium drug susceptibility intestinal flora laying hens
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Medical appraisal of Chinese military aircrew with abnormal results of coronary computed tomographic angiography
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作者 Jia Zeng Yao Zhao +4 位作者 Di Gao Xiang Lu Jing-Jing Dong Yan-Bing Liu Bin Shen 《World Journal of Cardiology》 2024年第9期522-530,共9页
BACKGROUND Coronary artery diseases can cause myocardial ischemia and hypoxia,angina pectoris,myocardial infarction,arrhythmia,and even sudden death led to inflight incapacitation of aircrew.As the main cause of groun... BACKGROUND Coronary artery diseases can cause myocardial ischemia and hypoxia,angina pectoris,myocardial infarction,arrhythmia,and even sudden death led to inflight incapacitation of aircrew.As the main cause of grounding due to illness,they severe threats to the health and fighting strength of military aircrew.Early warning in an early and accurate manner and early intervention of diseases possibly resulting in inflight incapacitation are key emphases of aeromedical support in clinic.AIM To figure out the flight factors and clinical characteristics of military aircrew with abnormal results of coronary artery computed tomographic angiography(CTA),thereby rendering theoretical references for clinical aeromedical support of military flying personnel.METHODS The clinical data of 15 flying personnel who received physical examinations in a military medical center from December 2020 to June 2023 and were diagnosed with coronary artery diseases by coronary artery CTA were collected and retrospectively analyzed,and a descriptive statistical analysis was conducted on their onset age,aircraft type and clinical data.RESULTS The 15 military flying personnel diagnosed with coronary artery diseases by coronary artery CTA were composed of 9 pilots,1 navigator and 5 air combat service workers.Multi-vessel disease was detected in 9 flying personnel,among which 8(88.9%)were pilots.Flying personnel with multi-vessel disease had higher content of cholesterol,low-density lipoprotein cholesterol and apolipoprotein B than those with single-vessel disease.CONCLUSION Coronary artery diseases are the major heart disease for the grounding of flying personnel due to illness,which can lead to inflight incapacitation.Coronary artery CTA is conducive to early detection and early intervention treatment of such diseases in clinic. 展开更多
关键词 military Flying personnel Coronary artery disease Medical appraisal
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Ultra reliability and massive connectivity provision in integrated internet of military things(IoMT)based on tactical datalink
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作者 Li Bing Yating Gu +4 位作者 Lanke Hu Li Bowen Yang Lihua Jue Wang Yue Yin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期386-398,共13页
One of the major challenges arising in internet of military things(IoMT)is accommodating massive connectivity while providing guaranteed quality of service(QoS)in terms of ultra-high reliability.In this regard,this pa... One of the major challenges arising in internet of military things(IoMT)is accommodating massive connectivity while providing guaranteed quality of service(QoS)in terms of ultra-high reliability.In this regard,this paper presents a class of code-domain nonorthogonal multiple accesses(NOMAs)for uplink ultra reliable networking of massive IoMT based on tactical datalink such as Link-16 and joint tactical information distribution system(JTIDS).In the considered scenario,a satellite equipped with Nr antennas servers K devices including vehicles,drones,ships,sensors,handset radios,etc.Nonorthogonal coded modulation,a special form of multiple input multiple output(MIMO)-NOMA is proposed.The discussion starts with evaluating the output signal to interference-plus-noise(SINR)of receiver filter,leading to the unveiling of a closed-form expression for overloading systems as the number of users is significantly larger than the number of devices admitted such that massive connectivity is rendered.The expression allows for the development of simple yet successful interference suppression based on power allocation and phase shaping techniques that maximizes the sum rate since it is equivalent to fixed-point programming as can be proved.The proposed design is exemplified by nonlinear modulation schemes such as minimum shift keying(MSK)and Gaussian MSK(GMSK),two pivotal modulation formats in IoMT standards such as Link-16 and JITDS.Numerical results show that near capacity performance is offered.Fortunately,the performance is obtained using simple forward error corrections(FECs)of higher coding rate than existing schemes do,while the transmit power is reduced by 6 dB.The proposed design finds wide applications not only in IoMT but also in deep space communications,where ultra reliability and massive connectivity is a keen concern. 展开更多
关键词 Satellite network Deep space communications Internet of military things Non-orthogonal multiple access MIMO LINK-16 JITDS
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基于Civil 3D部件编辑器的矿山排土场参数化设计研究
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作者 苏高飞 梁耀 侯亚博 《现代矿业》 CAS 2024年第2期100-103,共4页
近年来,民用建筑行业BIM技术得到迅速发展,将其应用于有色冶金矿山设计工作势在必行,改变以往人工计算、应用AutoCAD插件出图的现状。为实现排土场参数化设计,结合排土场设计经验和计算机语言,基于Civil 3D部件编辑器(SAC)研究了参数化... 近年来,民用建筑行业BIM技术得到迅速发展,将其应用于有色冶金矿山设计工作势在必行,改变以往人工计算、应用AutoCAD插件出图的现状。为实现排土场参数化设计,结合排土场设计经验和计算机语言,基于Civil 3D部件编辑器(SAC)研究了参数化设计流程;针对排土场横断面形式,创建了多级边坡部件参数化模型,实现了快速建模、三维模型到二维图纸的转换以及排土场库容精确计算。基于SAC的排土场三维参数化设计技术促进了设计效率和精度的提升,总结形成了参数化设计技术在排土场设计过程中的应用流程,为类似项目提供参考。 展开更多
关键词 civil 3D部件编辑器 排土场 参数化设计
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基于Civil3D在道路交叉口正向设计的研究与应用
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作者 刘帮 《山东工业技术》 2024年第2期92-96,共5页
针对目前BIM正向设计所存在的出图效率低、设计工具操作不习惯、数据互通丢失率高等问题,结合某二级公路交叉口,将Civil 3D作为其正向设计的工具,开展基于Civil 3D在道路交叉口正向设计的研究,对道路交叉设计、道路优化、三维可视化等... 针对目前BIM正向设计所存在的出图效率低、设计工具操作不习惯、数据互通丢失率高等问题,结合某二级公路交叉口,将Civil 3D作为其正向设计的工具,开展基于Civil 3D在道路交叉口正向设计的研究,对道路交叉设计、道路优化、三维可视化等方面进行关键技术研究。研究结果表明,通过对地形数据优化分析,生成三维地形曲面,结合Civil 3D智能化、智慧化设计的特点,生成施工图级别的正向设计成果。工程应用结果表明,使用Civil 3D进行道路交叉口的正向设计,可以提高设计效率、减少设计错误、考虑不全面等问题,减少后期因为施工、地质突发情况对设计变更的影响。 展开更多
关键词 BIM正向设计 道路交叉口 civil 3D 关键技术研究
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Exploring the Applications of Digital Twin Technology in Enhancing Sustainability in Civil Engineering:A Review
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作者 Jiamin Huang Ping Wu +2 位作者 Wangxin Li Jun Zhang Yidong Xu 《Structural Durability & Health Monitoring》 EI 2024年第5期577-598,共22页
With the advent of the big data era and the rise of Industrial Revolution 4.0,digital twins(DTs)have gained sig-nificant attention in various industries.DTs offer the opportunity to combine the physical and digital wor... With the advent of the big data era and the rise of Industrial Revolution 4.0,digital twins(DTs)have gained sig-nificant attention in various industries.DTs offer the opportunity to combine the physical and digital worlds and aid the digital transformation of the civil engineering industry.In this paper,605 documents obtained from the search werefirst analysed using CiteSpace for literature visualisation,and an author co-occurrence network,a keyword co-occurrence network,and a keyword clustering set were obtained.Next,through a literature review of 86 papers,this paper summarises the current status of DT application in civil engineering based on a review of the origins,concepts,and implementation techniques of DTs,and it introduces the application of DTs in the full project lifecycle.This study shows that DTs have great potential to address many of the challenges faced by civil engineering.In this regard,the paper also presents some thoughts on the future directions of DT research. 展开更多
关键词 Digital twins civil engineering full lifecycle literature visualisation analysis
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基于Civil 3D进行符合国标的超高加宽设计
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作者 王振宇 康宁 《河南建材》 2024年第1期4-7,共4页
BIM的快速发展为道路设计提供了新的发展契机。作为一款成熟的道路设计BIM软件,无论是设计规范,还是装配部件,Civil 3D都支持自主定义,这为道路行业BIM的发展提供了一个很好的设计平台。在各等级道路中,道路的超高加宽设计对于行车的安... BIM的快速发展为道路设计提供了新的发展契机。作为一款成熟的道路设计BIM软件,无论是设计规范,还是装配部件,Civil 3D都支持自主定义,这为道路行业BIM的发展提供了一个很好的设计平台。在各等级道路中,道路的超高加宽设计对于行车的安全性与舒适性至关重要,但是在进行路线超高加宽设计时,Civil 3D所依托的是美国标准规范。为了让设计更适合中国道路实际情况,根据中国路线设计规范修编Civil 3D的超高加宽设计文件是至关重要的,可以为中国标准下的公路行业BIM设计发展提供一定的帮助。 展开更多
关键词 BIM civil 3D 道路设计 超高加宽 中国标准
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The Positive Significance of Confucian Civilization in Peace Building
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作者 PU Jingxin ZHENG Hongju 《International Relations and Diplomacy》 2024年第1期18-25,共8页
The Confucian emphasis on benevolence and empathy can be applied in conflict resolution processes.When parties in conflict embrace these values,it becomes easier to find common ground,compromise,and work towards peace... The Confucian emphasis on benevolence and empathy can be applied in conflict resolution processes.When parties in conflict embrace these values,it becomes easier to find common ground,compromise,and work towards peaceful solutions.Confucian civilization,with its emphasis on ethics,harmony,and diplomacy,offers valuable contributions to peace-building efforts in the contemporary world.By promoting virtuous leadership,fostering cross-cultural understanding,and emphasizing ethical governance,Confucianism can play a positive role in achieving and maintaining global peace.Confucianism continues to exert significant influence in the contemporary world,particularly in the context of peace-building efforts.This article explores the positive significance of Confucian civilization in contributing to peace-building endeavors globally. 展开更多
关键词 Confucian civilization CONFUCIANISM BENEVOLENCE peace-building HARMONY cross-cultural understanding
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Association between Mental Health Literacy and Workplace Well-Being of Chinese Grassroots Civil Servants:The Chain Mediating Effects of Regulatory Emotional Self-Efficacy and Resilience
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作者 Yi Tang Yajun Zhao +4 位作者 Zihan Jin Shengnan Wu Zhijun Zhang Ju Zhou Ling Zhou 《International Journal of Mental Health Promotion》 2024年第7期559-568,共10页
This study aimed to investigate the relationship between mental health literacy(MHL)and workplace well-being(WWB)of Chinese grassroots civil servants,with regulatory emotional self-efficacy(RESE)and resilience as media... This study aimed to investigate the relationship between mental health literacy(MHL)and workplace well-being(WWB)of Chinese grassroots civil servants,with regulatory emotional self-efficacy(RESE)and resilience as mediating variables.A questionnaire survey was conducted among Chinese grassroots civil servants,with a valid sample size of 2673 after excluding missing values and conducting relevant data processing.The PROCESS was used to examine the relationship between MHL,RESE,resilience,and WWB.The study found that MHL among grassroots civil servants was positively and significantly correlated with WWB(r=0.73,p<0.01).RESE partially mediated the relationship between MHL and WWB(β=0.25,95%CI[0.22,0.28]).Resilience partially mediated the relationship between MHL and WWB(β=0.22,95%CI[0.19,0.26]).MHL had a positive effect on WWB through the chain mediating effect of RESE and resilience(β=0.05,95%CI[0.03,0.07]).There is a close relationship between MHL and WWB,where Chinese grassroots civil servants with higher levels of MHL can develop stronger RESE and resilience,leading to higher WWB.The results of this study remind organizational institutions of Chinese grassroots civil servants that enhancing MHL,RESE,and resilience is an important pathway to promoting their WWB. 展开更多
关键词 Mental health literacy workplace well-being regulatory emotional self-efficacy RESILIENCE Chinese grassroots civil servants
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基于Midas Civil的桥梁承载力检算分析
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作者 唐颖林 汤维 《北方交通》 2024年第3期14-17,21,共5页
文章以衡山路跨陇海立交桥第1联边跨、中跨受力最不利梁为工程研究案例,基于Midas Civil有限元软件对桥梁承载力进行检算分析,并介绍桥梁工程检算参数取值。通过Midas Civil建立桥梁模型,模拟桥梁结构和荷载,对比分析桥梁元结构的承载... 文章以衡山路跨陇海立交桥第1联边跨、中跨受力最不利梁为工程研究案例,基于Midas Civil有限元软件对桥梁承载力进行检算分析,并介绍桥梁工程检算参数取值。通过Midas Civil建立桥梁模型,模拟桥梁结构和荷载,对比分析桥梁元结构的承载能力和桥梁实际承载能力,结果表明该桥梁结构满足规范荷载等级使用要求。研究可为同类型工程提供经验参考。 展开更多
关键词 桥梁工程 承载能力 荷载 Midas civil
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基于Midas Civil在大型履带吊车作用下的钢栈桥结构设计
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作者 杨林 孙广 +1 位作者 李潇 张泽明 《建筑安全》 2024年第7期47-51,61,共6页
为保证钢栈桥可以在大型履带吊车作用下安全使用,以四川省成都市某景观人行桥项目为例,对钢栈桥进行针对性的结构设计,采用Midas Civil有限元软件进行钢栈桥建模和结构分析,并简要阐述了钢栈桥的施工要点。通过模型建立过程的加载方式... 为保证钢栈桥可以在大型履带吊车作用下安全使用,以四川省成都市某景观人行桥项目为例,对钢栈桥进行针对性的结构设计,采用Midas Civil有限元软件进行钢栈桥建模和结构分析,并简要阐述了钢栈桥的施工要点。通过模型建立过程的加载方式、工况的介绍,计算分析了各个工况的钢栈桥的变形值、应力、稳定性,计算结果均满足容许值,为工程的实施提供了理论数据支持。 展开更多
关键词 桥梁工程 钢栈桥 Midas civil
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The Historical Position and Value Dimensions of Human Rights Civilization
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作者 鲁广锦 PAN Yingzhao 《The Journal of Human Rights》 2024年第1期11-41,共31页
Human beings are the mainstay and the ultimate goal of civilization.The history of human civilization is a continuous struggle to realize the respect,liberation,protection,and development of humanity.Human rights are ... Human beings are the mainstay and the ultimate goal of civilization.The history of human civilization is a continuous struggle to realize the respect,liberation,protection,and development of humanity.Human rights are an achievement of humanity and a symbol of progress,and the human rights civilization is an important component of human civilization.Understanding and interpreting human rights from the perspective of human rights civilization means that human rights are not only a concept or an idea but also a grand historical and long-term social practice.Up to now,the development of human rights civilization has roughly experienced four awakening eras:initialization,revolution,popularization,and globalization.In terms of its value dimensions,it has the characteristics of progressiveness,diversity,commonality,inclusiveness,indivisibility,openness,and so on.The historical position of human rights civilization and the development of its value dimensions have shown to the world that human rights are the common wealth of humanity,and human rights belong to all mankind;human rights are historical,concrete,and developmental;the concept of human rights is constantly evolving,and its connotations and categories are constantly expanding;achieving the free and well-rounded development of every person is the highest value realm of human rights civilization.The Chinese modernization endows Chinese civilization with modern strength and opens up new horizons for human rights civilization.The new pattern of human rights civilization to be created by Chinese modernization not only possesses the common characteristics of human rights civilization but also enjoys Chinese characteristics based on its own national conditions,enriching and developing the diversity of human rights civilization for all mankind. 展开更多
关键词 human rights civilization four awakening eras of human rights value dimensions of human rights Chinese modernization new pattern of human rights civilization with Chinese characteristics
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基于MIDAS Civil的连续梁桥偏心桥墩受力分析探讨
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作者 李强 《山西交通科技》 2024年第2期86-90,共5页
在桥梁的设计中,偏心桥墩对总体设计有着较大影响,合理的桥墩形式不仅可以使整体结构受力更加合理,而且也能使上、下部结构的造型协调一致、轻巧美观。魏榆路左转匝道9号墩采用了偏心桥墩设计,为了探讨合理的偏心桥墩结构形式,运用MIDAS... 在桥梁的设计中,偏心桥墩对总体设计有着较大影响,合理的桥墩形式不仅可以使整体结构受力更加合理,而且也能使上、下部结构的造型协调一致、轻巧美观。魏榆路左转匝道9号墩采用了偏心桥墩设计,为了探讨合理的偏心桥墩结构形式,运用MIDAS Civil有限元软件对9号墩进行了建模分析,计算结果表明采用盖梁两侧做不对称悬挑的桥墩形式可进一步提高结构的安全系数,可为今后类似的偏心结构体系桥墩的设计提供参考。 展开更多
关键词 连续梁桥 下部结构 偏心桥墩 有限元分析 MIDAS civil
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Civil 3D在某砂石料场运输道路设计中的应用
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作者 胡锦峰 《云南水力发电》 2024年第8期170-172,共3页
为提高道路的设计质量及工作效率,依据现场实测高程数据及相关资料,针对性地研究了Civil 3d在道路设计中的应用。获取实测高程数据建立原始地形曲面,直观地表达了现场地形的变化情况。通过Civil 3D软件的横、纵断面设计功能,建立了道路... 为提高道路的设计质量及工作效率,依据现场实测高程数据及相关资料,针对性地研究了Civil 3d在道路设计中的应用。获取实测高程数据建立原始地形曲面,直观地表达了现场地形的变化情况。通过Civil 3D软件的横、纵断面设计功能,建立了道路的三维模型。利用Civil 3D参数化设计对象联动的功能,对道路进行动态调整,提高了设计效率,对比不同设计方案下的开挖量情况,对方案进行迭代优化。 展开更多
关键词 civil 3D 数字地面模型 道路三维设计 动态更新
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BDSec:Security Authentication Protocol for BeiDou-Ⅱ Civil Navigation Message
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作者 Wu Zhijun Zhang Yuan +2 位作者 Yang Yiming Wang Peng Yue Meng 《China Communications》 SCIE CSCD 2024年第6期206-218,共13页
Due to the lack of authentication mechanism in BeiDou navigation satellite system(BDS),BD-Ⅱ civil navigation message(BDⅡ-CNAV) are vulnerable to spoofing attack and replay attack.To solve this problem,we present a s... Due to the lack of authentication mechanism in BeiDou navigation satellite system(BDS),BD-Ⅱ civil navigation message(BDⅡ-CNAV) are vulnerable to spoofing attack and replay attack.To solve this problem,we present a security authentication protocol,called as BDSec,which is designed by using China’s cryptography Shangyong Mima(SM) series algorithms,such as SM2/4/9 and Zu Chongzhi(ZUC)algorithm.In BDSec protocol,both of BDⅡ-CNAV and signature information are encrypted using the SM4 algorithm(Symmetric encryption mechanism).The encrypted result is used as the subject authentication information.BDSec protocol applies SM9 algorithm(Identity-based cryptography mechanism) to protect the integrity of the BDⅡ-CNAV,adopts the SM2 algorithm(Public key cryptosystem) to guarantee the confidentiality of the important session information,and uses the ZUC algorithm(Encryption and integrity algorithm) to verify the integrity of the message authentication serial number and initial information and the information in authentication initialization sub-protocol respectively.The results of the SVO logic reasoning and performance analysis show that BDSec protocol meets security requirements for the dual user identity authentication in BDS and can realize the security authentication of BDⅡ-CNAV. 展开更多
关键词 BDII civil navigation messages(BDIICNAV) BeiDou navigation satellite system(BDS) identity-based cryptography mechanism navigation message authentication protocol(BDSec)
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The Path,Trends,and Approaches of the Civilization Evolution of Rural Marriage Forms
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作者 Renxiu Chen 《Review of Educational Theory》 2024年第1期6-9,共4页
Rural marriage has characteristics such as close relationship with labor production,deep integration of traditional culture,shy and introverted expression of subjective emotions,and illegal and rough marriage.The civi... Rural marriage has characteristics such as close relationship with labor production,deep integration of traditional culture,shy and introverted expression of subjective emotions,and illegal and rough marriage.The civilization evolution of rural marriage forms is moving towards a path that is conducive to the development of production and the pursuit of happiness for farmers,the construction of rural spiritual civilization,and the comprehensive development of rural society.This study analyzes the direction of the evolution of rural marriage form civilization,predicts the trend of rural marriage form civilization evolution,and proposes the future path of rural marriage form civilization evolution,including adhering to human’s most original value expectations of marriage life,drawing nourishment from excellent traditional Chinese culture,and continuously adjusting marriage and family policy tools to keep up with changes in the world of life. 展开更多
关键词 Rural Marriage Forms civilization Evolution Marriage Squeeze civilized Rationality
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基于Civil 3D和MIKE 21耦合的全二维溃堤洪水动态模拟应用
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作者 郭文 马梦梦 鲍珊珊 《水利规划与设计》 2024年第7期57-62,共6页
为探究基于Civil 3D和MIKE 21耦合的全二维水动力模型在溃堤洪水动态模拟中的实际应用效果,文章采用实测地形资料,利用Civil 3D创建河道内、外全二维高精度地形曲面,结合MIKE 21构建全二维水动力模型,计算得到不同溃口工况下提防沿线的... 为探究基于Civil 3D和MIKE 21耦合的全二维水动力模型在溃堤洪水动态模拟中的实际应用效果,文章采用实测地形资料,利用Civil 3D创建河道内、外全二维高精度地形曲面,结合MIKE 21构建全二维水动力模型,计算得到不同溃口工况下提防沿线的淹没深度及流场分布。结果表明,采用Civil 3D创建河道内地形曲面较横断面数据概化更为精准,更能直观展示河道内洪水演进变化。该研究为工程设计提供了科学可靠的数据支持,对于指导防洪工程建设具有重要意义。 展开更多
关键词 civil 3D MIKE21 溃堤洪水 防洪工程
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