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The Middle Miocene lobe-shaped and band-shaped submarine fans in the Lingshui Sag,Qiongdongnan Basin:source-to-sink system,genesis and implication
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作者 Xingzong Yao Congjun Feng +2 位作者 Hongjun Qu Min Zhang Daming Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第4期61-79,共19页
Deepwater oil and gas exploration is the key to sustainable breakthroughs in petroleum exploration worldwide.The Central Canyon gas field has confirmed the Lingshui Sag is a hydrocarbon-generating sag,and the deepwate... Deepwater oil and gas exploration is the key to sustainable breakthroughs in petroleum exploration worldwide.The Central Canyon gas field has confirmed the Lingshui Sag is a hydrocarbon-generating sag,and the deepwater reservoirs in the Lingshui Sag still have more fabulous oil and gas exploration potential.Based on drilling data and three-dimensional(3D)seismic data,this paper uses seismic facies analysis,seismic attribute analysis,and coherence slice analysis to identify the types of submarine fans(lobe-shaped and band-shaped submarine fans)that developed in the Lingshui Sag during the Middle Miocene,clarify the source-to-sink system of the submarine fans and discuss the genesis mechanism of the submarine fans.The results show that:(1)the deepwater source-to-sink system of the Lingshui Sag in the Middle Miocene mainly consisted of a“delta(sediment supply)-submarine canyon(sediment transport channel)-submarine fan(deepwater sediment sink)”association;(2)the main factor controlling the formation of the submarine fans developed in the Lingshui Sag was on the relative sea level decline;and(3)the bottom current reworked the lobe-shaped submarine fan that developed in the northern Lingshui Sag and formed the band-shaped submarine fan with a greater sand thickness.This paper aims to provide practical geological knowledge for subsequent petroleum exploration and development in the deepwater area of the Qiongdongnan Basin through a detailed analysis of the Middle Miocene submarine fan sedimentary system developed in the Lingshui Sag. 展开更多
关键词 submarine fan source-to-sink system genesis mechanism Middle Miocene Lingshui Sag
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Sedimentary architecture of submarine channel-lobe systems under different seafloor topography:Insights from the Rovuma Basin offshore East Africa
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作者 Mei Chen Sheng-He Wu +6 位作者 Rui-Feng Wang Jia-Jia Zhang Peng-Fei Xie Min Wang Xiao-Feng Wang Ji-Tao Yu Qi-Cong Xiong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期125-142,共18页
Seafloor topography plays an important role in the evolution of submarine lobes.However,it is still not so clear how the shape of slope affects the three-dimensional(3-D)architecture of submarine lobes.In this study,w... Seafloor topography plays an important role in the evolution of submarine lobes.However,it is still not so clear how the shape of slope affects the three-dimensional(3-D)architecture of submarine lobes.In this study,we analyze the effect of topography factors on different hierarchical lobe architectures that formed during Pliocene to Quaternary in the Rovuma Basin offshore East Africa.We characterize the shape,size and growth pattern of different hierarchical lobe architectures using 3-D seismic data.We find that the relief of the topographic slope determines the location of preferential deposition of lobe complexes and single lobes.When the topography is irregular and presents topographic lows,lobe complexes first infill these depressions.Single lobes are deposited preferentially at positions with higher longitudinal(i.e.across-slope)slope gradients.As the longitudinal slope becomes higher,the aspect ratio of the single lobes increases.Lateral(i.e.along-slope)topography does not seem to have a strong influence on the shape of single lobe,but it seems to affect the overlap of single lobes.When the lateral slope gradient is relatively high,the single lobes tend to have a larger overlap surface.Furthermore,as the average of lateral slope and longitudinal slope gets greater,the width/thickness ratio of the single lobe is smaller,i.e.sediments tend to accumulate vertically.The results demonstrate that the shape of slopes more comprehensively influences the 3-D architecture of lobes in natural deep-sea systems than previously other lobe deposits and analogue experiments,which helps us better understand the development and evolution of the distal parts of turbidite systems. 展开更多
关键词 Submarine fan Seafloor topography Sedimentary architecture Slope system SW Indian ocean
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Study of a Dual-sided Multiple Fans System with a Piezoelectric Actuator
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作者 Hsiao-Kang Ma Yi-Tseng Li Ching-Po Lin 《Journal of Thermal Science》 SCIE EI CAS CSCD 2015年第5期432-441,共10页
A dual-sided multiple fans system with a piezoelectric actuator ("D-MFPA"), which is able to drive eight passive vibrating fans and provide two-directional air flows by using only one piezoelectric actuator, has b... A dual-sided multiple fans system with a piezoelectric actuator ("D-MFPA"), which is able to drive eight passive vibrating fans and provide two-directional air flows by using only one piezoelectric actuator, has been investigated in this study. Moreover, two types of the fan designs, viz. magnetic fan (MF) and composite magnetic fan (CMF) were also explored. In the investigation of the MF, the results indicated that the resonance frequency of the D-MFPA increased from 27.6 Hz to 66 Hz as the length of the carbon fiber plate (L) decreased from 55 mm to 35 mm. It also decreased the amplitude of the D-MFPA from 12.4mm to 4.8 mm. For CMF, the results showed that the resonance frequency decreased when the length of the Mylar plate (Et) increased, and the maximum decrease was from 66 Hz to 45 Hz when L= 35 mm and Er= 30 mm. Dimensionless heat convection number (MD_MFPA) was defined to describe and quantify the improvement in the thermal performance. The results showed that the optimal MO-MFPA of the single piezoelectric fan was 1,58 for cooling one heat source. By contrast, under the same power consumption, the D-MFPA not only cooled two heat sources but also displayed better thermal performance. 展开更多
关键词 D-MFPA resonance frequency composite magnetic fan thermal performance
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Flood risk on arid alluvial fans:a case study in the Joghatay Mountains,Northeast Iran
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作者 Kaveh GHAHRAMAN Balázs NAGY 《Journal of Mountain Science》 SCIE CSCD 2023年第5期1183-1200,共18页
Among the common hazards related to alluvial fans,flooding is one of the most important.Nonetheless,in populated alluvial fans,not only the natural processes are effective in floods,but the artificial structures and m... Among the common hazards related to alluvial fans,flooding is one of the most important.Nonetheless,in populated alluvial fans,not only the natural processes are effective in floods,but the artificial structures and modifications can change the behavior of flooding and its potential risks.This study aims to indicate the flood-prone landforms in a set of populated alluvial fans in an arid region and investigate the role of anthropogenic activities in controlling/exacerbating flooding in alluvial fans.To achieve this goal,15 Ground Range Detected in High resolution(GRDH)SAR Sentinel-1 images,covering a total of 24 alluvial fans,were acquired.Pre-processing and post-processing steps were applied to all images to identify flood-prone sections of the studied alluvial fans.The results showed that feeder channels,spreading sites,and wide interfluves are the most flood-prone landforms of alluvial fans.In terms of anthropogenic modifications to mitigate flooding,a rampart system is distributed in the study area.Ramparts are levee like structures formed from the fan material.They aim to mitigate flood hazard on residential areas,infrastructures,and agricultural lands of the study area.Results show that the rampart system can reduce the danger of floods,but it cannot be considered a long-term solution.Therefore,a comprehensive flood protection system distributed throughout the whole alluvial fan system is needed.Results also reveal that in regions where flood monitoring is challenging,SAR images can be used as a freely available data set to monitor and identify flooding hotspots. 展开更多
关键词 Alluvial fan FLOOD Anthropogenic activities Rampart Sentineli SAR
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Sedimentary Processes and Depositional Characteristics of Coarse-grained Subaqueous Fans along Steep Slopes in a Lacustrine Rift Basin:A Case Study from the Dongying Depression,Bohai Bay Basin,China
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作者 YANG Baoliang QIU Longwei +3 位作者 YANG Yongqiang Kouassi Louis KRA DONG Daotao Danish KHAN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第2期526-547,共22页
Coarse-grained subaqueous fans are vital oil and gas exploration targets in the Bohai Bay basin,China.The insufficient understanding of their sedimentary processes,depositional patterns,and controlling factors restric... Coarse-grained subaqueous fans are vital oil and gas exploration targets in the Bohai Bay basin,China.The insufficient understanding of their sedimentary processes,depositional patterns,and controlling factors restricts efficient exploration and development.Coarse-grained subaqueous fans in the Yong′an area,Dongying Depression,are investigated in this study.These fans include nearshore subaqueous fans,and sublacustrine fans,and their sedimentary processes,depositional patterns and distribution characteristics are mainly controlled by tectonic activity and paleogeomorphology.Nearshore subaqueous fans developed near the boundary fault during the early–middle deposition stage due to strong tectonic activity and large topographic subsidence.Early sublacustrine fans developed at the front of the nearshore subaqueous fans in the area where the topography changed from gentle to steep along the source direction.While the topography was gentle,sublacustrine fans did not develop.During the late weak tectonic activity stage,late sublacustrine fans developed with multiple stages superimposed.Frequent fault activity and related earthquakes steepened the basin margin,and the boundary fault slopes were 25.9°–34°.During the early–middle deposition stage,hyperpycnal flows triggered by outburst floods developed.During the late deposition stage,with weak tectonic activity,seasonal floods triggered hyperpycnal flows,and hybrid event beds developed distally. 展开更多
关键词 sedimentary processes depositional characteristics paleogeomorphology coarse-grained subaqueous fan lacustrine rift basin Dongying Depression
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Diversity of depositional architecture and sandbody distribution of sublacustrine fans during forced regression: A case study of Paleogene Middle Sha 3 Member in Dongying Sag, Bohai Bay Basin, East China
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作者 WU Qianran XIAN Benzhong +5 位作者 GAO Xianzhi TIAN Rongheng ZHANG Haozhe LIU Jianping GAO Yukun WANG Pengyu 《Petroleum Exploration and Development》 SCIE 2023年第4期894-908,共15页
Currently, the differences in gravity flow deposits within different systems tracts in continental lacustrine basins are not clear. Taking the middle submember of the third member of Paleogene Shahejie Formation(Sha 3... Currently, the differences in gravity flow deposits within different systems tracts in continental lacustrine basins are not clear. Taking the middle submember of the third member of Paleogene Shahejie Formation(Sha 3 Member) in the Shishen 100 area of the Dongying Sag in the Bohai Bay Basin as an example, the depositional architecture of sublacustrine fans during forced regression and the impact of the fourth-order base-level changes on their growth were investigated using cores, well logs and 3D seismic data. Sublacustrine fans were mainly caused by hyperpycnal flow during the fourth-order base-level rise, while the proportion of slump-induced sublacustrine fans gradually increased during the late fourth-order base-level fall. From rising to falling of the fourth-order base-level, the extension distance of channels inside hyperpycnal-fed sublacustrine fans reduced progressively, resulting in the transformation in their morphology from a significantly channelized fan to a skirt-like fan. Furthermore, the depositional architecture of distributary channel complexes in sublacustrine fans changed from vertical aggradation to lateral migration, and the lateral size of individual channel steadily decreased. The lobe complex's architectural patterns evolved from compensational stacking of lateral migration to aggradational stacking, and the lateral size of individual lobe steadily grew. This study deepens the understanding of depositional features of gravity flow in high-frequency sequence stratigraphy and provides a geological foundation for the fine development of sublacustrine fan reservoirs. 展开更多
关键词 Bohai Bay Basin Dongying Sag Paleogene Shahejie Formation sublacustrine fan hyperpycnal flow gravity flow base-level depositional architecture
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基于云边协同的通用板级自动测试系统方案设计
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作者 林连冬 于化男 +2 位作者 朱贺 蓝润泽 陈滨 《黑龙江大学自然科学学报》 CAS 2024年第4期485-495,共11页
针对当前数字电路自动测试领域,对通用板级自动测试系统进行了设计,完成了系统方案的设计开发和测试验证。为了解决通用板级自动测试系统的测试数据量大、本地存储容量不足、测试向量与被测试目标无法自动化匹配、无法进行批量快速测试... 针对当前数字电路自动测试领域,对通用板级自动测试系统进行了设计,完成了系统方案的设计开发和测试验证。为了解决通用板级自动测试系统的测试数据量大、本地存储容量不足、测试向量与被测试目标无法自动化匹配、无法进行批量快速测试等问题,采用云边协同架构设计了通用板级自动测试系统,避免了大量数据传输和数据集中式处理,使得云端计算资源能够集中解决关键数据处理任务。为了提高板级测试平台的通用性,使平台适配不同接口的电路板,同时具有高速网络数据处理能力,系统选用精简命令集处理器和现场可编程门阵列(Advanced RISC machines,Filed programmable gate array,ARM+FPGA)的异构计算平台作为边缘设备。为了提高系统的测试效率,采用模块化的设计思想,系统硬件测试平台设计了多总线分布式结构。系统采用扇出导向(Fan-out-oriented,FAN)算法生成测试向量,并基于浏览器/服务器(Brower/Server,B/S)架构设计了用户操作界面,用户可通过浏览器进行测试操作,完成板级自动故障测试,并自动生成故障诊断报告。实验结果表明,对两个待测板卡进行测试验证,通用板级自动测试系统可以自动识别目标板卡,自动匹配测试向量,进行自动测试,生成测试报表。基于云边协同的通用板级自动测试系统提高了测试效率,满足数字电路板卡出厂前批量测试的需求,具有实际应用价值。 展开更多
关键词 云边协同 通用板级自动测试 FAN算法 异构计算平台
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粉丝(Fans)在中国的接受流变研究 被引量:7
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作者 马孝幸 辛红娟 《理论月刊》 CSSCI 北大核心 2013年第2期88-91,共4页
人类文明的发展在于各文明之间的交流与互动,在于从其他民族借用一些观念和物质。不同语言对外来语词的吸收主要发生在语言接触、文化接触的过程中。本文依据爱德华.赛义德关于理论旅行的创见,对后现代大众文化语词之一的"fans&qu... 人类文明的发展在于各文明之间的交流与互动,在于从其他民族借用一些观念和物质。不同语言对外来语词的吸收主要发生在语言接触、文化接触的过程中。本文依据爱德华.赛义德关于理论旅行的创见,对后现代大众文化语词之一的"fans"在汉语语境的接受与消化进行历时描述,分析fans在不同时期的汉语翻译,力图揭示典型外来大众娱乐文化语词在中国的接受与变形。文章分析指出,"fans"一词从英语语境来到汉语语境,在发音、意义、用法等方面一直在与接受语文化相调适,"粉丝"一词的语义转换与流行,不仅体现当下人们求新求变的审美心理需求,也从一个侧面体现了异质文化接受从完全陌生的比附释义阶段向体认他者之"异"的宏观过程。 展开更多
关键词 fans 旅行理论 接受
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基于FANS的温室风机通风性能测试 被引量:2
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作者 张智 Steven E Ford +1 位作者 Richard S Gates 邹志荣 《农业机械学报》 EI CAS CSCD 北大核心 2014年第11期311-316,共6页
试验采用Fansassessmentnumerationsystem(FANs)为现场监测系统,利用位置上下移动持续运行的螺旋桨风速计和静压传感器对风机通风性能进行测试。试验共测定3个玻璃温室内3种类型共9个排风风机在不同工况下静压5.O~61.5Pa范围内的... 试验采用Fansassessmentnumerationsystem(FANs)为现场监测系统,利用位置上下移动持续运行的螺旋桨风速计和静压传感器对风机通风性能进行测试。试验共测定3个玻璃温室内3种类型共9个排风风机在不同工况下静压5.O~61.5Pa范围内的通风量和能源消耗。结果显示,风机防护网的存在及清洁状况对通风量的影响低于5%;塑料百叶窗风机比相同配置的铝制百叶窗风机通风量和能效分别平均高13.1%、15.1%;参数完全相同的风机能效差异最高达12.7%;胶带驱动的风机转速减少16.1%时通风量平均降低38.7%;温室内静压超过30Pa时风机能耗显著增加。 展开更多
关键词 温室 风机性能 fans 通风量 能效
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Platform Evolution in an Oligo-Miocene Back-arc Basin:An Example from the Central Iran Basin
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作者 Masoud SHARIFI-YAZDI Amirhossein ENAYATI +2 位作者 Jamal SALEHI AGHDAM Mohammad BAHREHVAR Seyed Mustafa REZAEI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期185-206,共22页
The Qom Formation is the most important hydrocarbon reservoir target in Central Iran.The Qom platform developed in a back-arc basin during the Oligo-Miocene due to the closing of the Tethyan Seaway.This formation cons... The Qom Formation is the most important hydrocarbon reservoir target in Central Iran.The Qom platform developed in a back-arc basin during the Oligo-Miocene due to the closing of the Tethyan Seaway.This formation consists of a variety of carbonate and non-carbonate facies deposited on a platform ranging from supratidal to basin.A combination of tectonic and eustatic events led to some lateral and vertical facies variations in the study area.Six third-order depositional sequences and related surfaces were identified regarding vertical facies changes in the studied sections of this Oligo-Miocene succession.According to all results and data,this succession was initially deposited during the Chattian upon a distally steepened ramp of siliciclastic-carbonate composition,including the Bouma sequence.Then,from the late Chattian to the Aquitanian,the platform changed into a homoclinal carbonate ramp with a gentle profile.With respect to tectonic activity,this phase was a calm period during the deposition of the Qom Formation.Finally,a drowned carbonate platform and a rimmed shelf emerged during the Burdigalian,terminated by the continental deposits of the Upper Red Formation.Regarding all geological characteristics,three main tectono-eustatic evolutionary phases have been recognized in the Qom back-arcbasin. 展开更多
关键词 carbonate ramp depositional facies submarine fan EUSTASY basement faults back-arc basin
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Effects of desert plant communities on soil enzyme activities and soil organic carbon in the proluvial fan in the eastern foothills of the Helan Mountain in Ningxia,China
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作者 SHEN Aihong SHI Yun +8 位作者 MI Wenbao YUE Shaoli SHE Jie ZHANG Fenghong GUO Rui HE Hongyuan WU Tao LI Hongxia ZHAO Na 《Journal of Arid Land》 SCIE CSCD 2024年第5期725-737,共13页
It is of great significance to study the effects of desert plants on soil enzyme activities and soil organic carbon(SOC)for maintaining the stability of the desert ecosystem.In this study,we studied the responses of s... It is of great significance to study the effects of desert plants on soil enzyme activities and soil organic carbon(SOC)for maintaining the stability of the desert ecosystem.In this study,we studied the responses of soil enzyme activities and SOC fractions(particulate organic carbon(POC)and mineral-associated organic carbon(MAOC))to five typical desert plant communities(Convolvulus tragacanthoides,Ephedra rhytidosperma,Stipa breviflora,Stipa tianschanica var.gobica,and Salsola laricifolia communities)in the proluvial fan in the eastern foothills of the Helan Mountain in Ningxia Hui Autonomous Region,China.We recorded the plant community information mainly including the plant coverage and herb and shrub species,and obtained the aboveground biomass and plant species diversity through sample surveys in late July 2023.Soil samples were also collected at depths of 0–10 cm(topsoil)and 10–20 cm(subsoil)to determine the soil physicochemical properties and enzyme activities.The results showed that the plant coverage and aboveground biomass of S.laricifolia community were significantly higher than those of C.tragacanthoides,S.breviflora,and S.tianschanica var.gobica communities(P<0.05).Soil enzyme activities varied among different plant communities.In the topsoil,the enzyme activities of alkaline phosphatase(ALP)andβ-1,4-glucosidas(βG)were significantly higher in E.rhytidosperma and S.tianschanica var.gobica communities than in other plant communities(P<0.05).The topsoil had higher POC and MAOC contents than the subsoil.Specifically,the content of POC in the topsoil was 18.17%–42.73%higher than that in the subsoil.The structural equation model(SEM)indicated that plant species diversity,soil pH,and soil water content(SWC)were the main factors influencing POC and MAOC.The soil pH inhibited the formation of POC and promoted the formation of MAOC.Conversely,SWC stimulated POC production and hindered MAOC formation.Our study aimed to gain insight into the effects of desert plant communities on soil enzyme activities and SOC fractions,as well as the drivers of SOC fractions in the proluvial fan in the eastern foothills of the Helan Mountain and other desert ecosystems. 展开更多
关键词 proluvial fan desert plant community soil enzyme activity particulate organic carbon mineral-associated organic carbon Helan Mountain
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Coupling relationship and genetic mechanisms of shelf-edge delta and deep-water fan source-to-sink:A case study in Paleogene Zhuhai Formation in south subsag of Baiyun Sag,Pearl River Mouth Basin,China
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作者 TANG Wu XIE Xiaojun +5 位作者 XIONG Lianqiao GUO Shuai XU Min XU Enze BAI Haiqiang LIU Ziyu 《Petroleum Exploration and Development》 SCIE 2024年第3期589-603,共15页
The coupling relationship between shelf-edge deltas and deep-water fan sand bodies is a hot and cutting-edge field of international sedimentology and deep-water oil and gas exploration.Based on the newly acquired high... The coupling relationship between shelf-edge deltas and deep-water fan sand bodies is a hot and cutting-edge field of international sedimentology and deep-water oil and gas exploration.Based on the newly acquired high-resolution 3D seismic,logging and core data of Pearl River Mouth Basin(PRMB),this paper dissected the shelf-edge delta to deep-water fan(SEDDF)depositional system in the Oligocene Zhuhai Formation of Paleogene in south subsag of Baiyun Sag,and revealed the complex coupling relationship from the continental shelf edge to deep-water fan sedimentation and its genetic mechanisms.The results show that during the deposition of the fourth to first members of the Zhuhai Formation,the scale of the SEDDF depositional system in the study area showed a pattern of first increasing and then decreasing,with deep-water fan developed in the third to first members and the largest plane distribution scale developed in the late stage of the second member.Based on the development of SEDDF depositional system along the source direction,three types of coupling relationships are divided,namely,deltas that are linked downdip to fans,deltas that lack downdip fans and fans that lack updip coeval deltas,with different depositional characteristics and genetic mechanisms.(1)Deltas that are linked downdip to fans:with the development of shelf-edge deltas in the shelf area and deep-water fans in the downdip slope area,and the strong source supply and relative sea level decline are the two key factors which control the development of this type of source-to-sink(S2S).The development of channels on the continental shelf edge is conducive to the formation of this type of S2S system even with weak source supply and high sea level.(2)Deltas that lack downdip fans:with the development of shelf edge deltas in shelf area,while deep water fans are not developed in the downdip slope area.The lack of“sources”and“channels”,and fluid transformation are the three main reasons for the formation of this type of S2S system.(3)Fans that lack updip coeval deltas:with the development of deep-water fans in continental slope area and the absence of updip coeval shelf edge deltas,which is jointly controlled by the coupling of fluid transformation at the shelf edge and the“channels”in the continental slope area. 展开更多
关键词 shelf-edge delta deep-water fan source-to-sink system Paleogene Zhuhai Formation Baiyun Sag Pearl River Mouth Basin
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Debris Fan Produced by Failure of Canyon-Blocking Pyroclastic Flows
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作者 Michael L. Cummings 《Journal of Water Resource and Protection》 CAS 2024年第5期328-360,共33页
Ash-rich pyroclastic flows from the cataclysmic eruption of Mount Mazama (~7700 yr. B. P.), Cascade volcanic arc, Oregon, entered and blocked the narrow, bedrock-lined canyon of the Williamson River approximately 35 t... Ash-rich pyroclastic flows from the cataclysmic eruption of Mount Mazama (~7700 yr. B. P.), Cascade volcanic arc, Oregon, entered and blocked the narrow, bedrock-lined canyon of the Williamson River approximately 35 to 44 km from the source volcano. The blockage impounded a body of water which then released producing four stratigraphic units in the downstream debris fan. The four stratigraphic units are a boulder core comprised of locally sourced bedrock boulders and three sand-rich units including a fine-grained sand unit, a sandy pumice gravel (±basalt/hydrovolcanic tuff) unit, and a pumice pebble-bearing, crystal-rich sand unit. Hand-drilled auger holes up to ~1.6 m deep were used to obtain samples of the sand-rich units. Units were delimited using surface and down-hole observations, composition and texture, estimated density, statistical parameters of grain size, and vertical and lateral distribution of properties. Overtopping followed by rapid incision into the ash-rich pyroclastic flows progressively cleared the canyon, but a bedrock knickpoint near the head of the canyon limited the volume of debris available for transport to about 0.04 km<sup>3</sup> to 0.08 km<sup>3</sup>. Co-deposition of bedrock boulders and lithic-rich sand was followed by rapid deposition with minimal reworking of remobilized pyroclastics. Continued draining of the impounded lake sent hyperconcentrated flows onto the debris fan depositing pumice-rich gravels that graded upward to crystal-rich sands. 展开更多
关键词 Outburst Flood Mount Mazama Debris Fan Canyon Blockage Pyroclastic Flows
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G^1端点约束的Bézier曲线曲面的Ribs和Fans
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作者 黄伟贤 王国瑾 《计算机研究与发展》 EI CSCD 北大核心 2011年第9期1781-1787,共7页
为了得到Bézier曲线曲面的更加适用于网络传输的分解和重构算法,研究了带1阶端点(角点)约束的Bézier曲线曲面的Ribs和Fans,并且得到了相应的曲线曲面的光滑部分和细节部分.反过来,给定Bézier曲线的光滑部分和细节部分,... 为了得到Bézier曲线曲面的更加适用于网络传输的分解和重构算法,研究了带1阶端点(角点)约束的Bézier曲线曲面的Ribs和Fans,并且得到了相应的曲线曲面的光滑部分和细节部分.反过来,给定Bézier曲线的光滑部分和细节部分,给出了重构原曲线的算法.另外,还把Ribs和Fans的概念与算法推广到三角Bézier曲面.1张n次的三角Bézier曲面能够分解为1张n-1次的Rib、1张n-3次的Fan和3条n-4次Bézier曲线(Fans).数值例子表明对曲线曲面的光滑部分和细节部分的分解是更优与更有效的. 展开更多
关键词 BÉZIER曲线 BÉZIER曲面 三角BÉZIER曲面 Ribs和fans 端点约束
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广义的Ky Fan定理
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作者 何秋锦 李永刚 《周口师范学院学报》 CAS 2024年第2期1-4,共4页
矩阵行列式是矩阵分析学中一个很重要的分支,利用矩阵外代数,可以把行列式的计算转换成矩阵的迹算子。首先,从典型的Ky Fan定理出发,给出了该定理的一个等价形式,并且利用Brunn-Minkowski不等式给出了定理的证明。其次,利用凸函数的性质... 矩阵行列式是矩阵分析学中一个很重要的分支,利用矩阵外代数,可以把行列式的计算转换成矩阵的迹算子。首先,从典型的Ky Fan定理出发,给出了该定理的一个等价形式,并且利用Brunn-Minkowski不等式给出了定理的证明。其次,利用凸函数的性质,得到了Ky Fan定理的一个更一般的表示形式。 展开更多
关键词 外代数 凸函数 BRUNN-MINKOWSKI不等式 Ky Fan定理
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双星图的LI矩阵的Ky Fan k-范数
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作者 郑馨 戴浩波 金启宇 《哈尔滨商业大学学报(自然科学版)》 CAS 2024年第3期342-345,共4页
树是连通的无圈图,研究树的拉普拉斯矩阵具有重要的图论和实际意义.设G是一个有n个点和m个边的图,A(G)和D(G)分别是图G的邻接矩阵和对角度矩阵,那么G的拉普拉斯矩阵定义为L(G)=D(G)-A(G).LI矩阵定义为LI(G)=L(G)-(2m/n)I_(n),其中I_(n)... 树是连通的无圈图,研究树的拉普拉斯矩阵具有重要的图论和实际意义.设G是一个有n个点和m个边的图,A(G)和D(G)分别是图G的邻接矩阵和对角度矩阵,那么G的拉普拉斯矩阵定义为L(G)=D(G)-A(G).LI矩阵定义为LI(G)=L(G)-(2m/n)I_(n),其中I_(n)是单位矩阵.图的LI矩阵的Ky Fan k-范数代表了拉普拉斯特征值和拉普拉斯特征值平均值之间距离的有序和.研究了双星图的LI矩阵的Ky Fan k-范数,证明了双星图的LI矩阵的Ky Fan k-范数满足文献[6]中提出的猜想. 展开更多
关键词 双星图 拉普拉斯矩阵 LI矩阵 Ky Fan k-范数 能量 奇异值
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FAN1基因c.1799A>T突变与巨核细胞性间质性肾炎的关联
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作者 刘珍玉 张俊宁 +2 位作者 杨雪丽 王广宇 侯显良 《华夏医学》 CAS 2024年第3期48-53,共6页
目的探究巨核细胞性间质性肾炎(KIN)与FAN1基因突变的关联性。方法2022年10月,发现一个家族聚集性肾炎家系。对家系成员进行全外显子组测序以确定候选基因,并通过Alpine分析、遗传变异判读和Sanger测序分析该基因。结果肾病家系先证者... 目的探究巨核细胞性间质性肾炎(KIN)与FAN1基因突变的关联性。方法2022年10月,发现一个家族聚集性肾炎家系。对家系成员进行全外显子组测序以确定候选基因,并通过Alpine分析、遗传变异判读和Sanger测序分析该基因。结果肾病家系先证者临床表型为肾炎,先证者母亲检出FAN1基因c.1799A>T突变。对家系中杂合性成员采用Sanger测序,也检测到相同的突变基因,依据美国医学遗传学与基因组学学会(ACMG)推荐指南,将其归类为意义不明的基因突变。本研究中的家系性肾炎表型与KIN部分相符。结论本研究中家系性肾炎的表型与FAN1基因c.1799A>T位点突变有密切关联。 展开更多
关键词 肾炎 FAN1基因 巨核细胞性间质性肾炎 全外显子组测序
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“fans”汉译语素构词的组合方法及其理据
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作者 刘禀诚 《井冈山大学学报(社会科学版)》 2019年第1期108-114,共7页
"fans"汉译语素构词在组合形态上包括内部组合形态与外部组合形态,前者又可分为音译、意译系列;在理据上包括词源理据、社会文化理据与认知理据。"fans"汉译语素构造的词语多为粉丝团名称,它们一般为非贬义的主观... "fans"汉译语素构词在组合形态上包括内部组合形态与外部组合形态,前者又可分为音译、意译系列;在理据上包括词源理据、社会文化理据与认知理据。"fans"汉译语素构造的词语多为粉丝团名称,它们一般为非贬义的主观量名词或知名事物。 展开更多
关键词 fans 汉译 构词 组合方法 理据
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Sedimentary Facies Characteristics of Chang 6 and Chang 7 Members of Yanchang Formation in Heshui Area, China
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作者 Xinyuan Liu Shunzhi Yang +1 位作者 Shunchao Gou Sen Chang 《Journal of Geoscience and Environment Protection》 2024年第9期182-197,共16页
This paper takes Chang 6 and Chang 7 of Yanchang Formation in Heshui area of China as the research object. This study first divides the strata of Chang 6 and Chang 7. According to the review data, significant geologic... This paper takes Chang 6 and Chang 7 of Yanchang Formation in Heshui area of China as the research object. This study first divides the strata of Chang 6 and Chang 7. According to the review data, significant geological activities have caused a large settlement of the strata in this area. During the Chang 6 period, a lacustrine basin sedimentary system developed, reaching its peak in the Chang 7 period. The Chang 6 and Chang 7 members primarily feature deep-water gravity flow sedimentary systems, which can be categorized into three subfacies: outer fan, middle fan, and inner fan. These systems also exhibit turbidite fan sedimentary patterns, ranging from deep lake to semi-deep lake facies. By examining these sedimentary models, we can identify different types of turbidite deposits. Understanding the process of gravity flow deposition and the evolution of ancient lakes is crucial for guiding oil and gas exploration and conducting paleogeographic research. 展开更多
关键词 Stratigraphic Division Gravity Flow Deposition Turbidity fans Oil and Gas Exploration
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Capturing CO2 Emissions in the George C. Wallace Tunnel: A Case Study
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作者 Gabe Canitz Cole Ciesta +4 位作者 Klint Green Justin Sanders Jason Valencia Jeremy Willingham Daniel Fonseca 《Intelligent Control and Automation》 2024年第3期83-94,共12页
This paper describes the design of a ventilation system to be paired with a carbon capture system. The ventilation system utilizes the geometry of the George C. Wallace tunnel, located in the City of Mobile, Alabama, ... This paper describes the design of a ventilation system to be paired with a carbon capture system. The ventilation system utilizes the geometry of the George C. Wallace tunnel, located in the City of Mobile, Alabama, USA to capture and redirect emissions to a direct air capture (DAC) device to sequester 25% of the total CO2 mass generated from inside the tunnel. The total CO2 mass rate for the westbound traffic between the week-day hours of 7 a.m. and 6 p.m. has been estimated between 2,300 to 3,000 lbs./hr. By sequestering these emissions, the overall surrounding air quality was shown to be improved to a level that mirrors that from the pre-US industrial era of 270 ppm. 展开更多
关键词 CO2 Capture Tunnel Ventilation Air Flow Analysis Jet Fan Sizing
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