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Study on the Environmental Impact of Oil and Gas Field Development on the Ecological Red Line Area 被引量:1
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作者 Yunshi XIONG Zhihong GUO +1 位作者 Tao LIANG Qichen GAO 《Meteorological and Environmental Research》 CAS 2020年第3期70-73,80,共5页
To cooperate with the five ministries and commissions of the state to carry out joint investigation on the environmentally sensitive areas involved in oil and gas exploration and development,for the problems found in ... To cooperate with the five ministries and commissions of the state to carry out joint investigation on the environmentally sensitive areas involved in oil and gas exploration and development,for the problems found in survey,containing complex type and numerous amount of ecologically sensitive space and ecological red line involved in oil and gas field enterprises,scientific nature of delimitation,lack of strong support of laws and regulations for forced withdrawal of oil and gas production facilities in these areas,some countermeasures and suggestions were proposed,such as further evaluating and combing scope and functional zoning of existing environmentally sensitive areas and ecological red lines,treating differently,enhancing pertinence of prohibition in ecologically sensitive regions,declining blindness of the withdrawal of oil and gas facilities in environmentally sensitive areas,strengthening seriousness of approval of exploration and mining rights of oil and gas resources,and establishing strategic reserve exploration and hierarchical development mechanism. Moreover,oil and gas field enterprises should integrate more efforts to ① accelerate to find out the current situation of environmental quality,② adhere to developing in protection,and protecting in development,③ increase attention and participation strengthen of providing technical support for national oil and gas exploration and development strategy evaluation,④ accelerate communication and docking with local governments on the ecological red line,⑤ actively strive to be included in the positive list management of local governments,⑥ accelerate to establish and perfect primary database of oil and gas production and facilities construction,and ⑦ document management information system of the ecological red line. 展开更多
关键词 Oil and gas fields Exploration and development Ecological red line Environmentally sensitive area Environmental effect
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Analysis on the Relationship between Ecological Protection Red Line and Red Lines of Other Elements
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作者 Liu Jialin Wang Xiaojun 《Meteorological and Environmental Research》 CAS 2019年第5期66-69,73,共5页
Ecological protection red line is the minimum spatial area and territorial boundary line to be protected to realize the unification of economic,social and ecological benefits by increasing the national and regional ec... Ecological protection red line is the minimum spatial area and territorial boundary line to be protected to realize the unification of economic,social and ecological benefits by increasing the national and regional ecological capital stock,maintaining ecological security,improving people's livelihood,promoting the sustainable development of economy and society,and upgrading the function of natural ecosystem.There are connections and differences between ecological protection red line and the red lines of cultivated land,forestry ecology,water resources control and marine ecology.Essentially speaking,they are all to maintain national ecological security and social stability,and create a good living environment for the people. 展开更多
关键词 ECOLOGICAL protection red line CULTIVATED land red line Marine ECOLOGY red line
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Game Analysis and Mechanism Design of Ecological Protection Red Line for Ecologically Vulnerable Areas in Western China
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作者 LIU Jialin ZHU Qiang 《Journal of Landscape Research》 2018年第5期73-78,共6页
Drawing the ecological protection red line is to maintain the integrity and benign operation of the ecosystem within the area,and to ensure that the ecological environment is within the boundary of controllable ecolog... Drawing the ecological protection red line is to maintain the integrity and benign operation of the ecosystem within the area,and to ensure that the ecological environment is within the boundary of controllable ecological security.Taking the ecologically vulnerable areas in western China as the research object and using the game theory and literature analysis,this paper studied the game behavior of ecological protection red line in these areas.In addition,this paper also analyzed the stakeholders such as government,enterprises and the masses in the drawing of the ecological protection red line,and comprehensively analyzed the game strategies between the government and the masses,the government and enterprises,and the central and local governments and enterprises.On the basis of the analysis,it came up with a safeguard mechanism for the coordination of the interests of the ecological protection red line. 展开更多
关键词 Ecological y vulnerable areas Ecological protection red line GAME MECHANISM
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Study on the Delineation of Ecological Protection Red Line in Ecological Fragile Region of the West
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作者 Liu Jialin 《Meteorological and Environmental Research》 CAS 2018年第4期19-23,29,共6页
Ecological protection red line is one of the main contents in system construction of ecological civilization in China, and also reflects the trend and the will of the national eco-environment protection system refor... Ecological protection red line is one of the main contents in system construction of ecological civilization in China, and also reflects the trend and the will of the national eco-environment protection system reform. In this paper, taking ecological fragile area of the west as the research object, and using literature analysis, comparative analysis and other methods, the characteristics in ecological fragile area of the west are compre-hensively elaborated, and the relationship between ecological vulnerability and ecological protection red line is clarified, and the delineation theory and methods of ecological protection red line are analyzed, such as ecological suitability analysis, regional ecological security pattern and DPSIR model. Finally, key issues of ecological protection red line delineation in ecological fragile zone of the west are proposed. 展开更多
关键词 Ecological fragile region Ecological protection red line MECHANISM WEST
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通用正式发布新款土星Vue Red Line
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《世界汽车》 北大核心 2005年第12期12-12,共1页
在今年加利福尼亚车展上,通用正式亮相新款土星Vue Red Line,并公布了采用前轮驱动的新款土星Vue Red Line的市场售价为24485美元,比老款车型降低了1240美元。该车标配3.5L V6发动机,最大输出功率187KW,百公里油耗则在8.4L左右。
关键词 line red 土星 通用 最大输出功率 加利福尼亚 V6发动机 百公里油耗 前轮驱动 市场售价
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大众高尔夫GTI敞篷——Red Line
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作者 李文斌(图) 《汽车测试报告》 2013年第7期72-75,共4页
作为全世界大众粉最热爱的三个字母——GTI,它已经深深地印刻在“大众教徒”的心中,如果你也是其中一份子的话,那么你一定要来试试GTI家族的这位新成员。或许你没有听过R的大名,但你一定已经久仰了GTI的神威,虽然激进程度略逊一筹... 作为全世界大众粉最热爱的三个字母——GTI,它已经深深地印刻在“大众教徒”的心中,如果你也是其中一份子的话,那么你一定要来试试GTI家族的这位新成员。或许你没有听过R的大名,但你一定已经久仰了GTI的神威,虽然激进程度略逊一筹,但价格也的确更加诱人,它可以让普通人也有权利享受那强烈的推背感,并且还有着巨大的改装潜力,这让GTI成为了各大改装店的常客, 展开更多
关键词 大众高尔夫 GTI line red 改装
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基于Node-red的云端智能生产线控制系统设计与实现
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作者 陈玄烨 张鑫 +2 位作者 张景翔 文世华 李红利 《山东工业技术》 2024年第3期58-62,共5页
针对传统生产线在刚性生产过程中面临的成本过高、远程实施难、兼容性低等关键问题,基于目前中小企业的技术基础相对薄弱,无法将云计算平台、数据存储和处理等设备及技术运用到实际生产中的现状,本文利用西门子S7-1200 PLC作为核心控制... 针对传统生产线在刚性生产过程中面临的成本过高、远程实施难、兼容性低等关键问题,基于目前中小企业的技术基础相对薄弱,无法将云计算平台、数据存储和处理等设备及技术运用到实际生产中的现状,本文利用西门子S7-1200 PLC作为核心控制器,基于Node-red平台设计了成本低、兼容性高的云端智能生产线监控系统,便于实现对于生产线的监视和控制,提高生产效率与产品质量。现场运行表明,该系统运行稳定,满足智能生产线的设计要求,同时具备部署成本低、兼容性高的突出优势。 展开更多
关键词 工业物联网 Node-red 智能生产线 云端控制系统
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A Workable Solution for Reducing the Large Number of Vehicle and Pedestrian Accidents Occurring on a Yellow Light
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作者 Pranav Gupta Silki Arora 《Journal of Transportation Technologies》 2024年第1期82-87,共6页
Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the U.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada... Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the U.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada, during 2019, the National Collision Database shows that 28% of traffic fatalities and 42% of serious injuries occurred at intersections. Likewise, the U.S. National Highway Traffic Administration (NHTSA) found that about 40% of the estimated 5,811,000 accidents in the U.S. during the year studied were intersection-related crashes. In fact, a major survey by the car insurance industry found that nearly 85% of drivers could not identify the correct action to take when approaching a yellow traffic light at an intersection. One major reason for these accidents is the “yellow light dilemma,” the ambiguous situation where a driver should stop or proceed forward when unexpectedly faced with a yellow light. This situation is even further exacerbated by the tendency of aggressive drivers to inappropriately speed up on the yellow just to get through the traffic light. A survey of Canadian drivers conducted by the Traffic Injury Research Foundation found that 9% of drivers admitted to speeding up to get through a traffic light. Another reason for these accidents is the increased danger of making a left-hand turn on yellow. According to the National Highway Traffic Safety Association (NHTSA), left turns occur in approximately 22.2% of collisions—as opposed to just 1.2% for right turns. Moreover, a study by CNN found left turns are three times as likely to kill pedestrians than right turns. The reason left turns are so much more likely to cause an accident is because they take a driver against traffic and in the path of oncoming cars. Additionally, most of these left turns occur at the driver’s discretion—as opposed to the distressingly brief left-hand arrow at busy intersections. Drive Safe Now proposes a workable solution for reducing the number of accidents occurring during a yellow light at intersections. We believe this fairly simple solution will save lives, prevent injuries, reduce damage to public and private property, and decrease insurance costs. 展开更多
关键词 Traffic Accidents Yellow Light Traffic Light Signals INTERSECTION Crashes Collision Traffic Fatalities Traffic Injuries Vehicles SAFETY Speed Limit Driving Pedestrians Bicyclists MOTORCYCLISTS Caution line Yellow Light Dilemma Left Hand Turn on Yellow Distance Smart Road Technology Signs Signage Autonomous Vehicles AVs Road Safety IoT Internet of Things Infrastructure Accident reduction Driving Habits Stop line red Light Jumping Pedestrian Safety Caution Light Stopping at Intersection Safety at Intersections
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基于单调链的Red/Blue扫描线求交算法 被引量:5
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作者 杨崇俊 任应超 李津平 《武汉大学学报(信息科学版)》 EI CSCD 北大核心 2006年第9期835-838,共4页
提出了一种基于单调链的Red/Blue平面扫描线算法。该算法针对GIS中线段之间具有连接关系的特性,将平面连接线段集分解为一组单调链,通过对单调链的粗扫描过滤和对线段的精扫描求交,减少了扫描过程中的冗余计算,提高了线段集求交点的效... 提出了一种基于单调链的Red/Blue平面扫描线算法。该算法针对GIS中线段之间具有连接关系的特性,将平面连接线段集分解为一组单调链,通过对单调链的粗扫描过滤和对线段的精扫描求交,减少了扫描过程中的冗余计算,提高了线段集求交点的效率。实验证明,该算法对于处理具有连接关系的线段集的求交点问题具有很高的效率。 展开更多
关键词 单调链 red/Blue扫描线法 交点 两次扫描
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远红荧光蛋白HcRed基因的原核和真核表达及鉴定
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作者 何志强 薛渊 +8 位作者 石燕 杨恒 赵银霞 王楷文 周成林 王胜军 邵启祥 焦志军 许化溪 《江苏大学学报(医学版)》 CAS 2010年第1期17-20,共4页
目的:分别构建携带HcRed基因的PET28a(+)原核和PIRES真核载体,并分别在大肠埃希菌和鼠树突状细胞系(DC2.4)中表达、鉴定,为后续基因及蛋白的转染提供基础。方法:参照基因库中HcRed1基因序列,设计HcRedCDS全长引物,以含有HcRed的质粒为模... 目的:分别构建携带HcRed基因的PET28a(+)原核和PIRES真核载体,并分别在大肠埃希菌和鼠树突状细胞系(DC2.4)中表达、鉴定,为后续基因及蛋白的转染提供基础。方法:参照基因库中HcRed1基因序列,设计HcRedCDS全长引物,以含有HcRed的质粒为模板,通过PCR获得目的基因,并分别连接于PET28a(+)原核载体和PIRES真核载体。经PCR、酶切鉴定后,原核载体转化大肠埃希菌,经IPTG诱导表达;真核载体用脂质体转染DC2.4,G418筛选出克隆后,应用RT-PCR和流式细胞仪进行检测。结果:扩增出687 bp的HcRedCDS区序列,构建了原核和真核表达载体PET28a(+)/HcRed和PIRES/HcRed,分别于大肠埃希菌和DC2.4细胞系中成功表达。结论:成功构建HcRed基因的原核、真核表达载体,并分别在工程菌和细胞系中成功表达,为后续基因及融合蛋白的筛选、示踪和体内观测奠定了基础。 展开更多
关键词 远红荧光蛋白Hcred 树突状细胞系2.4 原核表达
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CHARACTERIZATION OF LACTATE DEHYDROGENASE ISOZYME PATTERN AND MORPHOLOGY OF THREE MARINE FISH CELL LINES 被引量:1
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作者 郭华荣 张士璀 +2 位作者 李红岩 童裳亮 相建海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第3期226-231,共6页
Three continuous marine fish cell lines of FG (i.e., Flounder Gill) from flounder ( Paralichthys olivaceus) gill, SPH (i.e., Sea Perch Heart) from sea perch ( Lateolabrax japonicus ) heart and RSBF (i.e., Red Sea... Three continuous marine fish cell lines of FG (i.e., Flounder Gill) from flounder ( Paralichthys olivaceus) gill, SPH (i.e., Sea Perch Heart) from sea perch ( Lateolabrax japonicus ) heart and RSBF (i.e., Red Sea Bream Fin) from red sea bream ( Pagrosomus major ) fin, were characterized by lactate dehydrogenase (LDH) isozyme and morphological analysis. The LDH isozyme patterns of these three cell lines and their corresponding tissues of origin were investigated and compared. The results showed: (1) No difference was found in the LDH isozyme patterns of FG and flounder gill tissue. However, the LDH isozyme patterns of SPH and RSBF were significantly different from their corresponding tissues of origin; (2) LDH isozyme patterns of FG, SPH and RSBF were markedly different from each other and could serve as genetic markers for species identification and detection of cross contamination. Morphological change analysis of these three cell lines in comparison to their original tissues indicated that FG cells still appeared epithelioid without morphological transformation. However, morphological changes were found in SPH and RSBF compared to their original tissues. Therefore, the cellular morphology was still plastic in the relatively stable culture conditions, and it was possible that change of LDH patterns was related to morphological changes of fish cells in vitro . 展开更多
关键词 cell line lactate dehydrogenase cellular morphology FLOUNDER sea perch red sea bream
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适用于异质网络的RED算法的改进与分析
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作者 吕杰 滕少华 朱朝晖 《计算机工程与设计》 CSCD 北大核心 2008年第17期4458-4460,4464,共4页
设计、分析和评价主动队列管理(AQM)算法成为近来网络拥塞问题研究的一个热点。随机提前探测(RED)算法作为AQM算法的典型代表,得到了较为广泛的应用。为了提高它的稳定性和公平性相继又开发出了ARED(adaptive RED),GRED(gentle RED),FRE... 设计、分析和评价主动队列管理(AQM)算法成为近来网络拥塞问题研究的一个热点。随机提前探测(RED)算法作为AQM算法的典型代表,得到了较为广泛的应用。为了提高它的稳定性和公平性相继又开发出了ARED(adaptive RED),GRED(gentle RED),FRED(flow RED)和WRED(weighted RED)等多种改进算法。在分析了RED算法及3种变种算法的基础上,比较了它们的优缺点,给出了适用于不同性质网络连接点处的WRED改进算法,用仿真试验证明了WRED改进算法在处理异质网络拥塞问题方面具有优势。 展开更多
关键词 拥塞控制 主动队列管理 随机提前探测算法 带权重的随机提前探测算法 链路算法
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Formulation Method and Management Principle for the Safety Base-line of Atmospheric Environmental Quality
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作者 Wang Wei 《Meteorological and Environmental Research》 CAS 2015年第8期33-39,共7页
The formulation of the safety base-line for atmospheric environmental quality is not only basic needs of mankind maintaining the quality of survival environment but also concrete measures of red line system for nation... The formulation of the safety base-line for atmospheric environmental quality is not only basic needs of mankind maintaining the quality of survival environment but also concrete measures of red line system for national ecological protection. It is urgent to solve the problem in current environmental management how to draft the safety basa-line of atmospheric environmental quality. To solve this problem, the connotation of safety base-line for atmospheric environmental quality is defined firstly, and then the indexes for atmospheric importance, sensitivity and vulnerability are generalized. Moreover, formulation methods for red, yellow and green lines of the safety base-line for atmospheric environmental quality are put forward ,and corresponding division principle and management principle are put forward finally. 展开更多
关键词 Atmospheric environment Safety base-line Ecological red line Management and countermeasure China
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Node-RED用于简化调整传送系统运行逻辑 被引量:3
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作者 林冬骁 沈嘉晨 +1 位作者 姜友相 胡浩林 《现代信息科技》 2023年第18期31-35,41,共6页
生产线运行逻辑更改时通常需要对其PLC程序进行调整,该任务一般需受过培训的工程师使用专业的工程电脑来完成。面对专业技术人员培养周期较长的现状,如何简化生产线运行逻辑调整难度,降低现场自动化编程的学习成本成为当务之急。对Node-... 生产线运行逻辑更改时通常需要对其PLC程序进行调整,该任务一般需受过培训的工程师使用专业的工程电脑来完成。面对专业技术人员培养周期较长的现状,如何简化生产线运行逻辑调整难度,降低现场自动化编程的学习成本成为当务之急。对Node-RED这一面向对象的编程工具在某药瓶传送系统运行逻辑调整时进行应用,使操作者通过较低的学习成本即可完成对该传送系统运行逻辑的调整,可以极大提高现场工作的效率。 展开更多
关键词 自动化编程 Node-red 智能生产线
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^(12)CO emission from the Red Rectangle
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作者 Pham Tuan Anh Pham Ngoc Diep +4 位作者 Do Thi Hoai Pham Tuyet Nhung Nguyen Thi Phuong Nguyen Thi Thao Pierre Darriulat 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第12期2213-2228,共16页
Observations of an unprecedented quality made by ALMA on the Red Rectangle of CO(3-2) and CO(6-5) emissions are analysed jointly with the aim of obtaining as simple as possible a description of the gas morphology ... Observations of an unprecedented quality made by ALMA on the Red Rectangle of CO(3-2) and CO(6-5) emissions are analysed jointly with the aim of obtaining as simple as possible a description of the gas morphology and kinematics. Evidence is found for polar conical outflows and for a broad equatorial torus in rotation and expansion. Simple models of both are proposed. Comparing CO(6-5) and CO(3-2) emissions provides evidence for a strong temperature enhancement over the polar outflows. Continuum emission (dust) is seen to be enhanced in the equatorial region. Observed asymmetries are briefly discussed. 展开更多
关键词 stars: AGB and post-AGB -- circumstellar matter -- radio-lines: stars-- planetary nebulae: individual red Rectangle)
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新时代“红色交通线”价值可视化设计研究
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作者 罗显怡 陈涛 宋珊 《包装工程》 CAS 北大核心 2024年第10期460-468,共9页
目的基于交通文化资源传播的多样性、泛在性、共享性与有效性需求,将红色交通线在特定历史时期及当代的价值引领作用以资源可视化的方式呈现,促进对交通文化的传承和发扬。方法以“可视化文化符号+产品载体”的形式,借助数字化技术实现... 目的基于交通文化资源传播的多样性、泛在性、共享性与有效性需求,将红色交通线在特定历史时期及当代的价值引领作用以资源可视化的方式呈现,促进对交通文化的传承和发扬。方法以“可视化文化符号+产品载体”的形式,借助数字化技术实现数据可视化及文化资源物化衍生,以揭示红色交通文化的发展脉络和新时代交通的变迁。涵盖了文化重构、品牌构建、可视化表达、产品设计、周边开发及营销管理等方面,以及系统化的交通文化产品研发途径。结果通过红色交通文化视觉性创意设计实践研究,探寻有效的文化重塑设计方法,以物化手段助力文化推广,实现对红色交通文化当代传承、价值传播的补充。结论以数字化手段提高抽象文化精神在社会普及过程中的接受度。有利于弘扬爱国主义传统、构建集体记忆,对深入研究和探讨红色交通文化,使其在当代得以活化、物化地发扬,以及增强文化自信都具有重要的理论和实践意义。 展开更多
关键词 红色交通线 价值性 可视化 设计方法 研究实践
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“三道红线”政策的房地产企业债务结构调整效应研究——基于双重差分法的经验证据
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作者 曹飞 马元恒 《技术经济》 CSSCI 北大核心 2024年第11期89-104,共16页
利用双重差分法考察“三道红线”政策的实施如何影响上市房企的债务结构。实证结果表明,“三道红线”政策对企业的流动负债有显著的负向影响,对长期负债有正向作用,优化调整了公司债务结构。进一步研究发现:①对于固定资产占比较低的企... 利用双重差分法考察“三道红线”政策的实施如何影响上市房企的债务结构。实证结果表明,“三道红线”政策对企业的流动负债有显著的负向影响,对长期负债有正向作用,优化调整了公司债务结构。进一步研究发现:①对于固定资产占比较低的企业而言,“三道红线”政策的实施对固定资产占比较高的企业债务结构的调整效应更明显;②国有企业和非东部地区的房企债务结构受到政策的冲击更大;③盈利能力较差,杠杆率较高的企业受到政策的冲击更大,其债务结构的调整效果更好;④政策出台使房地产企业加快营运资本流转,并有针对性地使用长债置换短债。本文在“房住不炒”的政策背景下识别出“三道红线”政策与房地产企业负债结构之间的因果关系,厘清了“三道红线”政策的作用机理,对优化房地产金融政策、降低房地产企业金融化水平有较好的借鉴意义。 展开更多
关键词 三道红线 债务结构 负债融资 双重差分法
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基于无迹卡尔曼滤波的液体火箭发动机故障诊断
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作者 许亮 芦弘炜 +1 位作者 王闻浩 薛薇 《载人航天》 CSCD 北大核心 2024年第4期516-525,共10页
针对火箭发动机故障数据难以获取的问题,设计了一种基于无迹卡尔曼滤波(UKF)的液体火箭发动机故障诊断算法。采用MATLAB/Simulink平台搭建了液体火箭发动机故障仿真模型,实现发动机正常运行仿真和预燃室氧阀门故障、氧主泵汽蚀、氢主涡... 针对火箭发动机故障数据难以获取的问题,设计了一种基于无迹卡尔曼滤波(UKF)的液体火箭发动机故障诊断算法。采用MATLAB/Simulink平台搭建了液体火箭发动机故障仿真模型,实现发动机正常运行仿真和预燃室氧阀门故障、氧主泵汽蚀、氢主涡轮叶片脱落3种故障仿真。将正常运行仿真值与设计值、试车值进行了对比。结果表明:模型参数与设计值最大误差不超过5%,仿真精度较高;仿真参数变化趋势与试车值基本一致,且稳态值误差较小。使用UKF算法求取发动机正常运行阈值范围,并对故障序列进行滤波处理,若故障数据连续3次超出阈值区间,且在0.1 s内有至少2个涡轮泵发出报警,则判定故障发生,故障发生时间为第2个涡轮泵报警时间。使用设计算法对3种故障序列进行诊断,判定故障发生时间分别为20.08 s、20.05 s、20.18 s。相比于传统红线阈值算法,文中所设计算法响应更为及时,且误报率较低。 展开更多
关键词 故障诊断 液体火箭发动机 无迹卡尔曼滤波 故障仿真 红线阈值算法
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大范围生态保护红线定标布局方法
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作者 马红 刘浩 +1 位作者 高林营 刘昌振 《城市勘测》 2024年第3期16-20,共5页
生态保护红线勘界定标是生态保护红线划定落实之后的又一项重要工作,是常态化监管的基础和前提。当前,生态保护红线勘界定标处于摸索试点阶段,国家层面缺乏具体指导细则,省市作为生态保护红线勘界定标工作的责任主体,只能结合实地因地... 生态保护红线勘界定标是生态保护红线划定落实之后的又一项重要工作,是常态化监管的基础和前提。当前,生态保护红线勘界定标处于摸索试点阶段,国家层面缺乏具体指导细则,省市作为生态保护红线勘界定标工作的责任主体,只能结合实地因地制宜开展,缺乏系统性、标准性。定标布局是勘界定标的关键环节,主要解决生态保护红线区域内界桩和标识牌的数量确定、拟埋设位置选择等问题。本文提出一种大范围生态保护红线定标布局方法,先将生态保护红线区域按一定尺度划分为格网单元,筛选出涉及生态保护红线边界的格网单元,再引入行政区域、人口数量、道路交通、地形类别等特征因子构建度量模型,进一步开展度量特征计算,根据特征阈值最终选定格网单元,并以最终选定的格网单元作为定标布局方案,指导界桩和标识牌数量设定及埋设点位选址。以重庆市为例开展大范围生态保护红线定标布局应用,为重庆全市域生态保护红线勘界定标工作提供了第一手资料,同时,验证了本文方法在指导省市实施生态保护红线定标布局的科学性和实用性。 展开更多
关键词 生态保护红线 国土空间规划 勘界定标 布局方案
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体外生产红细胞:进展与挑战 被引量:1
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作者 王辉 张进进 +1 位作者 陈立力 邢颜超 《协和医学杂志》 CSCD 北大核心 2024年第1期166-171,共6页
目前临床用血供不应求,尽管自体输血等血液保护技术可部分缓解此类情况,但红细胞作为主要的血液成分需求量巨大,而体外生产安全的红细胞则可解决这一难题。目前研究显示,可从胚胎干细胞、人诱导多能干细胞、脐带血、外周血和永生化红系... 目前临床用血供不应求,尽管自体输血等血液保护技术可部分缓解此类情况,但红细胞作为主要的血液成分需求量巨大,而体外生产安全的红细胞则可解决这一难题。目前研究显示,可从胚胎干细胞、人诱导多能干细胞、脐带血、外周血和永生化红系祖细胞系几种来源分化出成熟红细胞。本文就体外生产红细胞的来源及应用进行综述,并分析目前所面临的挑战,以期为输血治疗提供新思路。 展开更多
关键词 体外生产红细胞 胚胎干细胞 永生化红系祖细胞系 输血
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