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Geochronological, Sedimentary, Structural, and Metallogenic Characteristics of Southeast China during the Mesozoic: A General Review 被引量:2
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作者 Pengju Li Hongying Li 《International Journal of Geosciences》 2015年第9期1032-1047,共16页
The tectonic evolution of Southeast China during Late Mesozoic is a prominent topic. Numerous tectonic models on Late Mesozoic evolution ofSoutheast Chinahave been?published in the past 50 years. We synthesized many u... The tectonic evolution of Southeast China during Late Mesozoic is a prominent topic. Numerous tectonic models on Late Mesozoic evolution ofSoutheast Chinahave been?published in the past 50 years. We synthesized many up-to-date and precise zircon U-Pb ages, sedimentary strata, and regional structures and discussed the oxygen fugacity of magmas and related ore deposits. We also analyzed the most current tectonic models published by some scholars. A multistage tectonic stress evolution history during Late Mesozoic was constructed, which included the following stages: 1) Early-Middle Jurassic (196 - 175 Ma) extension, in which many bimodal volcanics formed;2) Middle-Late Jurassic (165 - 140 Ma) compression, which generated largescale gneissic granites, garnet-bearing granites, stratigraphic hiatus, and nappe structures;3) Early Cretaceous (140 ± 5 - 120 Ma) extension, which formed weakly deformed or undeformed granites, alkali granites, metamorphic core complexes, graben basins, and basic dike swarms;4) Early Cretaceous (120 - 110 Ma) compression, which generated nappe structures, volcanic hiatuses, and garnet-bearing granites;and 5) Early-Late Cretaceous (110 - 80 Ma) extension, which generated largescale bimodal volcanics, basic dike swarms, alkali granites, and graben basins. The Late Mesozoic tectonic evolution ofSoutheast Chinamay be attributed to the drifting history of the Paleo-Pacific plate. The drifting direction of the Paleo-Pacific plate has changed several times since 140 Ma, which led to major changes in the tectonicphenomena from Jurassic to Cretaceous and to the formation of Late Mesozoic mineral deposits. 展开更多
关键词 TECTONIC Evolution Late MESOZOIC ZIRCON u-PB Age Regional Structures se China
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Inspiration of Successful Experience of U.S. and European Enterprises Leveraging Sports Marketing on "Going Global" of Chinese Enterprises
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作者 Hailin Lu 《Journal of Sports Science》 2016年第4期250-255,共6页
With the globalization of sports event, sports marketing has become a promotion strategy of more and more enterprises. Chinese enterprises have also gradually realized the commercial val^e of sports. Sports marketing ... With the globalization of sports event, sports marketing has become a promotion strategy of more and more enterprises. Chinese enterprises have also gradually realized the commercial val^e of sports. Sports marketing has been paid increasing attention by enterprises as a means of brand promotion. Through the analysis of the sports marketing experience of five representative enterprises, Intel, Coca-cola, Herbalife, Omega and Babycare, this paper explores their successful experience, so as to assist Chinese enterprises in "going global" with the help of sports marketing. 展开更多
关键词 u.S.-Eu famous enterprises sports marketing experience inspiration.
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VB12负载纳米零价镍固定地下水中U(Ⅵ)/Se(Ⅳ)的效能研究
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作者 吴兴农 李小燕 +6 位作者 温馨 王澜 付晓辉 刘小亮 黄希 张益硕 刘波 《环境化学》 CAS CSCD 北大核心 2023年第11期4032-4042,共11页
本研究用液相还原法制备了VB12负载纳米零价镍(VB12@nZVNi)复合材料,通过动态试验探讨了复合材料原位固定地下水中U(Ⅵ)/Se(Ⅳ)的固定效果.运用Thomas、Yoon-Nelson模型对所得试验数据进行拟合,讨论VB_(12)@nZVNi固定U(Ⅵ)/Se(Ⅳ)的性能... 本研究用液相还原法制备了VB12负载纳米零价镍(VB12@nZVNi)复合材料,通过动态试验探讨了复合材料原位固定地下水中U(Ⅵ)/Se(Ⅳ)的固定效果.运用Thomas、Yoon-Nelson模型对所得试验数据进行拟合,讨论VB_(12)@nZVNi固定U(Ⅵ)/Se(Ⅳ)的性能.结果表明,VB_(12)@nZVNi材料对模拟U(Ⅵ)/Se(Ⅳ)污染地下水有着较好的固定效果,对U(Ⅵ)/Se(Ⅳ)的最大吸附量分别为106.96 mg·g^(-1)、103.92 mg·g^(-1).Yoon-Nelson、Thomas模型符合其动态吸附过程,且理论吸附量和半穿透率与实际值比较接近.因此,VB_(12)@nZVNi可以作为一种有前景的固定材料,用于含U(Ⅵ)/Se(Ⅳ)地下水的固定和净化处理. 展开更多
关键词 维生素B12 纳米零价镍 负载 铀(Ⅵ) 硒(Ⅳ) 地下水
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U-Pb Dating of Volcanic Rocks and Granites along the Wuyishan Belt:Constraints on Timing of Late Mesozoic Tectonic Events in Southeast China 被引量:14
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作者 XU Xianbing ZHANG Yueqiao +1 位作者 JIA Dong SHU Liangshu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第1期130-144,共15页
Five volcanic rock samples and two granite samples taken from the volcanic basins in western Fujian and southern Jiangxi were dated by using the zircon laser albation-inductively coupled plasma mass spectrometry U-Pb ... Five volcanic rock samples and two granite samples taken from the volcanic basins in western Fujian and southern Jiangxi were dated by using the zircon laser albation-inductively coupled plasma mass spectrometry U-Pb method. Together with previously dated ages, the dates obtained provide important constraints on the timing of late Mesozoic tectonic events in SE China. The volcanic rock samples yield ages of 183.1±3.5 Ma, ca. 141 Ma to 135.8±1.1 Ma, 100.4±1.5 to 97.6±1.1 Ma, confirming three episodes of late Mesozoic volcanic activities, which peaked at 180±5 Ma, 140±5 Ma and 100±5 Ma, respectively, along the Wuyishan belt. Moreover, based on field investigations of these volcano-sedimentary basins, we have recognized two compressional tectonic events along this belt. The early one was characterized by Upper Triassic to Middle Jurassic NNE-trending folds that were intruded by late Jurassic granites; and the late one caused the Lower Cretaceous volcano-sedimentary layer to be tilted. The dated age 152.9±1.4 Ma of the granitic samples from the Hetian granitic pluton in the Changting Basin and that from the Baishiding granitic pluton, 100.2±1.8 Ma, in the Jianning Basin, give the upper boundaries of these two tectonic events respectively. Hence, the late Mesozoic tectonic evolution of SE China was alternated between extension and compression. 展开更多
关键词 Late Mesozoic volcanic rocks LA-ICP-MS u-Pb compressional events Wuyishan Belt se China
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填料水泥导热性能实验及对U型地热井取热影响的数值模拟研究 被引量:1
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作者 齐治虎 姬玉平 +4 位作者 王迪 徐影 李亚辉 刘文强 刘均荣 《能源与环保》 2024年第2期70-76,共7页
地层与井筒之间的导热性能是以热传导为主的U型地热井技术取得成功应用的关键因素之一。针对U型地热井如何提升固井水泥的导热性能问题,采用室内实验和数值模拟方法研究了导热填料对固井水泥导热性能和取热效果的影响。研究结果表明,石... 地层与井筒之间的导热性能是以热传导为主的U型地热井技术取得成功应用的关键因素之一。针对U型地热井如何提升固井水泥的导热性能问题,采用室内实验和数值模拟方法研究了导热填料对固井水泥导热性能和取热效果的影响。研究结果表明,石墨相比于实验所用其他填料而言具有更好的提升固井水泥导热性能的潜力;随着石墨掺入比例的增加,固井水泥的导热系数近似线性增加,而抗压强度近似线性下降;高掺入比例的石墨固井水泥能显著提高工作介质在U型井水平段入口处的温度,但由于U型井换热主要发生在较长的水平段上,从长期运行来看过高的掺入比例并不能显著提高取热效果,建议固井材料中石墨掺入比例控制在10%左右。研究结果对U型地热井固井水泥导热填料类型筛选和掺入参数确定具有重要意义。 展开更多
关键词 u型地热井 固井水泥 导热性能 室内实验 数值模拟 取热效果
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Seed and Wasp Production in the Mutualism of Figs and Fig Wasps 被引量:1
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作者 YaoJin-yan ZhaoNan-xian +3 位作者 ChenYi-zhu JiaXiao-cheng DengYuan YuHui 《Forestry Studies in China》 CAS 2005年第1期25-28,共4页
Figs (Moracea: Ficus) and fig wasps (Hymenoptera: Chlocloids: Agaonideae) depend on each other to complete their reproduction. Monoecious fig species and their pollinating wasps are in conflict over the use of fig ov... Figs (Moracea: Ficus) and fig wasps (Hymenoptera: Chlocloids: Agaonideae) depend on each other to complete their reproduction. Monoecious fig species and their pollinating wasps are in conflict over the use of fig ovaries which can either produce one seed or one wasp. From observation on Ficus virens Ait., we showed that female flowers with outer layer of ovaries (near to the wall of syconium) had no significant difference from that with inner and interval layer of ovaries (near to the syconium cavity), in which most seeds and wasps were produced. This meant that fig tree provided the same potential resource for seed and wasps production. Observation indicated that there was usually only one foundress in syconium at female flower phase and no com- petition pollinators. Measurement of the style length of female flowers and the ovipositor of pollinators indicated that most ovaries could be reached by pollinator’s ovipositor. However, at the male flower phase, production of seeds was significantly more than that of wasps including non-pollinating wasps but there was no significant difference between seed and pollinating wasp production when without non-pollinating wasps produced. This result indicated that non-pollinating wasps competed ovaries not with seeds but with pollinating wasps for ovipositing. Bagged experiment showed that the sampling fig species was not self-sterile which was important for figs and wasps to survive bad season. Seed production in self-pollinated figs was not significantly different from total wasps in- cluding non-pollinating ones. This might be related with the weaker competition among wasps since bagged figs were not easy to reach by wasps from outside. 展开更多
关键词 FICuS Ficus wasp mutualism conflicts seed and wasp production seed and Wasp Production in the Mutualism of Figs and Fig Wasps Yao Jin-yan1 2 Zhao Nan-xian1 Chen Yi-zhu1%MuL% Jia Xiao-cheng1 2 Deng Yuan1 2 Yu Hui1 2 1South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 P. R. China 2Graduate School of the Chinese Academy of Sciences Beijing 100039 P. R. China ABSTRACT Figs (Moracea: Ficus) and fig wasps (Hymenoptera: Chlocloids: Agaonideae) depend on each other to complete their reproduction. Monoecious fig species and their pollinating wasps are in conflict over the use of fig ovaries which can either produce one seed or one wasp. from observation on Ficus virens Ait. we showed that female flowers with outer layer of ovaries (near to the wall of syconium) had no significant difference from that with inner and interval layer of ovaries (near to the syconium cavity) in which most seeds and wasps were produced. This meant that fig tree provided the same potential resource for seed and wasps production. Observation indicated that there was usually only one foundress in syconium at female flower phase and no com- petition pollinators. Measurement of the style length of female flowers and the ovipositor of pollinators indicated that most ovaries could be reached by pollinator’s ovipositor. However at the male flower phase production of seeds was significantly more than that of wasps including non-pollinating wasps but there was no significant difference between seed and pollinating wasp production when without non-pollinating wasps produced. This result indicated that non-pollinating wasps competed ovaries not with seeds but with pollinating wasps for ovipositing. Bagged experiment showed that the sampling fig species was not self-sterile which was important for figs and wasps to survive bad season. seed production in self-pollinated figs was not significantly different from total wasps in- cluding non-pollinating
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A numerical experiment for the simulating effects of Kuwait oil fire and volcanoes in Philippines and Japan on the general circulation and climate
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作者 Wang Jian(Beijing Meteorological College, Beijing 100081, China)Zhao Zongci(Chinese Academy of Meteorological Scienes, Beijing 100081, China)Sun Churong(National Meteorological Center, Beijing 100081, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1994年第2期189-199,共11页
With an AGCM/ mixed-layer ocean model, a numerical experiment to investigate the ef-fects of Kuwait oil fire and volcanoes in Philippines and Japan on atmospheric general cireulationand climate is camed out. It is sho... With an AGCM/ mixed-layer ocean model, a numerical experiment to investigate the ef-fects of Kuwait oil fire and volcanoes in Philippines and Japan on atmospheric general cireulationand climate is camed out. It is shown from the simulation that the effect of smoke on climate issignificant near the smoke sources, and quite weak-and-indirect in the distant areas. In the experi-ment, it is not found that the smoke had a significant effect on SST anomialy along the tropicaloceans and flood in Yangtze-Huaihe river's basin of China in the spring and summer of 1991. 展开更多
关键词 prediction smoke sensitive experiment (se) control experiment (CE).
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基于U-G-S合作的地方师范类院校教师教育模式研究
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作者 周华丽 孙晓鲲 张志斌 《北京联合大学学报》 CAS 2024年第6期25-29,43,共6页
高校—政府—中小学(university-government-school,U-G-S)合作是各国高度重视的教师教育模式,该模式由高校、政府和中小学结成战略合作伙伴关系,协同促进未来教师的培养。基于U-S合作的内涵分析,梳理了美国教师“专业发展学校”模式、... 高校—政府—中小学(university-government-school,U-G-S)合作是各国高度重视的教师教育模式,该模式由高校、政府和中小学结成战略合作伙伴关系,协同促进未来教师的培养。基于U-S合作的内涵分析,梳理了美国教师“专业发展学校”模式、英国“以中小学为基地的教师培训学校”模式、法国教师教育“职前职后一体化”模式、芬兰“研究本位”的教师培养模式等国外有代表性的未来教师教育模式,阐述了基于U-G-S合作的未来教师教育模式在中国的发展状况。结合应用型大学关于教师教育的探索实践,对基于U-G-S合作的地方师范类院校教师教育模式优化提出建议。 展开更多
关键词 u-G-S合作 未来教师 教师教育模式 国际经验 应用型大学 地方师范类院校
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新疆511铀矿床7号采区U-Se-Re-Mo等元素分布特点 被引量:4
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作者 曾爱花 《矿床地质》 CAS CSCD 北大核心 2012年第1期139-150,共12页
Re、Se是中国急需的紧缺矿种,对国家的资源战略与环境安全保障具有重要影响。新疆伊犁盆地511矿床在开采铀的过程中,发现了Re、Se和Mo等元素存在富集的现象。文章以511矿床7号采区为例,采取野外地质调查与室内分析测试及综合研究相结合... Re、Se是中国急需的紧缺矿种,对国家的资源战略与环境安全保障具有重要影响。新疆伊犁盆地511矿床在开采铀的过程中,发现了Re、Se和Mo等元素存在富集的现象。文章以511矿床7号采区为例,采取野外地质调查与室内分析测试及综合研究相结合的技术路线,以探求Re、Se、Mo等元素的分布特点及其与U元素富集之间的关系。研究表明,Re和Se在空间上与砂岩铀矿体密切共生,说明在511矿床中矿源等条件具备的情况下,7号采区内的层间氧化作用促使Re和Se富集成矿,证实了511铀矿床中与U密切相关的Se、Re等元素具有线状分布的特点。 展开更多
关键词 地球化学 RE se MO u 7号采区 511铀矿床 新疆
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基于Serv-U的文件传输程序(FTP)服务器在医学院校计算机实验教学中的应用 被引量:4
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作者 刘文艳 潘清 +2 位作者 杜菁 王珂 杨淼 《中国医学装备》 2017年第6期120-124,共5页
目的:基于Serv-U软件搭建实验室文件传输程序(FTP)服务器,加强学校计算机实验教学中文件存储、访问及数据共享。方法:在校园局域网中,利用Serv-U软件搭建实验室FTP服务器,通过创建和设置域、群组和用户并设置其属性值,实现数据文件存储... 目的:基于Serv-U软件搭建实验室文件传输程序(FTP)服务器,加强学校计算机实验教学中文件存储、访问及数据共享。方法:在校园局域网中,利用Serv-U软件搭建实验室FTP服务器,通过创建和设置域、群组和用户并设置其属性值,实现数据文件存储和方便访问和快速查看。结果:基于Serv-U的FTP服务器,为医学院校师生提供一个数据共享和自由访问的存储平台,能够满足对移动数据的使用需求,促进实验课程高效地开展,提高教学质量及教学效率。结论:搭建基于Serv-U的FTP服务器,在校园网内为师生提供了一个文件存储和访问平台,可有效促进计算机实验教学方式的改革和学生综合能力培养。 展开更多
关键词 seRV-u软件 文件传输程序 服务器 实验教学
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蓝牙功率放大器SE2425U及其应用
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作者 刘军 赵旭 《国外电子元器件》 2008年第1期52-54,共3页
SE2425U是SiGe半导体公司专为标准蓝牙和增强型数据速率应用而优化的微型功率放大器。符合蓝牙2.0规范和EDR协议,旨在提高性能和降低电流消耗量。介绍了SE2425U的特点、性能指标及引脚功能,并给出了便携式产品设计中的对比解决方案。
关键词 se2425u 功率放大器 蓝牙 评估板
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U型热管换热器对冷凝除湿机性能影响的实验研究 被引量:1
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作者 王莹 刘岳 +1 位作者 庞云凤 吴昊天 《冷藏技术》 2023年第1期48-52,共5页
传统冷凝除湿机因能耗较大发展受限,本文通过在冷凝除湿机上加装一组U型热管换热器,提高除湿机的除湿性能,达到节能目的。为验证改装效果分别进行预冷和再热实验,得到空气流经U型热管换热器的蒸发端与冷凝端温度变化的绝对值基本一致,说... 传统冷凝除湿机因能耗较大发展受限,本文通过在冷凝除湿机上加装一组U型热管换热器,提高除湿机的除湿性能,达到节能目的。为验证改装效果分别进行预冷和再热实验,得到空气流经U型热管换热器的蒸发端与冷凝端温度变化的绝对值基本一致,说明U型热管换热器在能耗不变的条件下可对能量进行回收并充分利用。在这一基础上本文进行不同入口空气温度下,加装U型热管换热器前、后除湿机性能影响实验,即控制入口空气温度分别为24℃、26℃、28℃、30℃、32℃、34℃,测定改装前后除湿机的除湿量,并计算单位功率除湿量。实验结果表明,能耗不变的情况下,加装U型热管换热器后的除湿机每小时除湿量提升8%,单位功率除湿量提升7.8%。 展开更多
关键词 冷凝除湿机 u型热管换热器 除湿性能影响实验
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切顶沿空留巷U+L型通风采场煤自燃风险判定研究 被引量:2
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作者 李宗翔 李宇航 胡东杰 《自然灾害学报》 CSCD 北大核心 2023年第6期240-246,共7页
为探究切顶沿空留巷首采面U+L型通风采空区煤自燃危险性,以蒙西棋盘井煤矿东区9-1#层11101工作面为工程背景开展研究。通过封闭耗氧实验,测定得出煤样的耗氧能力弱、不同氧体积分数下煤样的耗氧速度慢、窒熄氧气体积分数(煤耗氧临界值)... 为探究切顶沿空留巷首采面U+L型通风采空区煤自燃危险性,以蒙西棋盘井煤矿东区9-1#层11101工作面为工程背景开展研究。通过封闭耗氧实验,测定得出煤样的耗氧能力弱、不同氧体积分数下煤样的耗氧速度慢、窒熄氧气体积分数(煤耗氧临界值)为15%。通过现场实测确定切顶沿空留巷和工作面的两端压差和漏风分布,现场埋管实测得到回风侧的氧分布数据,搭建了切顶沿空留巷采场相似模拟实验台,得到采场的漏风移动规律。运用CFD仿真探究了切顶沿空留巷采空区的漏风与自燃氧化分布特征,得到采空区可能具有自燃危险的3个区域分别位于开切眼附近、靠近沿空留巷的5~10 m内和工作面后方。提出在尾巷注氮和沿空留巷边界注浆堵漏防灭火措施条件下,可将U+L型通风采空区自燃模式转化为U型通风采空区自燃模式的危险性判定,得到棋盘井矿采空区自燃氧化带的最大宽度为80 m,最低安全推进速度1.2 m/d,无自燃风险,为工程防灭火做出指导。 展开更多
关键词 切顶沿空留巷 封闭耗氧实验 窒熄氧体积分数 u%PLuS%L型自燃模式 自燃风险判定
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基于改进的3D U-Net骨盆CT影像多类分割 被引量:1
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作者 刘志 李兴春 +4 位作者 郑斌 谢小山 肖林 李迎新 秦传波 《现代电子技术》 2023年第3期47-51,共5页
骨盆CT影像精确分割是骨盆骨疾病的临床诊断和手术规划中非常重要的环节。针对目前2D骨盆分割方法对三维医学影像进行切片处理时损失空间信息的问题,提出了改进3D U-Net网络实现对骨盆CT影像3D自动分割。实验数据为公开数据集CTPelvic1K... 骨盆CT影像精确分割是骨盆骨疾病的临床诊断和手术规划中非常重要的环节。针对目前2D骨盆分割方法对三维医学影像进行切片处理时损失空间信息的问题,提出了改进3D U-Net网络实现对骨盆CT影像3D自动分割。实验数据为公开数据集CTPelvic1K共1184名患者骨盆CT影像,其中包含骶骨、左髋骨、右髋骨和腰椎四个部位标签。以3D U-Net骨干网络为基础,结合自注意力机制提出3D多类分割模型3D Trans U-Net,并使用迁移学习训练3D U-Net、V-Net、Attention U-Net作为对照实验。实验结果表明:3D Trans U-Net在测试集上整个骨盆区域、骶骨、左髋骨、右髋骨、腰椎Dice系数分别达到97.99%,96.70%,97.96%,97.95%,96.89%;Dice系数、豪斯多夫距离等评价指标均优于现有经典网络3D U-Net、V-Net、Attention U-Net。因此,改进的3D Trans U-Net对骨盆不同部位具有较好的分割效果,为精准医治骨盆骨疾病提供了一条有效的技术途径。 展开更多
关键词 骨盆CT影像 多类分割 3D Trans u-Net 数据采集 自注意力 实验测试
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U形槽防护燃气管道爆炸对下方隧道安全影响有效性分析 被引量:1
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作者 马佳惠 张泽文 +1 位作者 侯鑫 杨小彬 《科学技术与工程》 北大核心 2023年第25期10957-10964,共8页
铁路隧道的线路建设常与城市地下燃气管线有所交叉,以某市铁路下穿天然气管道为背景,为分析隧道上方天然气管道爆炸对隧道结构的影响,提出在燃气管道周围设立U形槽的隔离防护措施。通过理论计算燃气管道爆炸三硝基甲苯(trinitrotoluene,... 铁路隧道的线路建设常与城市地下燃气管线有所交叉,以某市铁路下穿天然气管道为背景,为分析隧道上方天然气管道爆炸对隧道结构的影响,提出在燃气管道周围设立U形槽的隔离防护措施。通过理论计算燃气管道爆炸三硝基甲苯(trinitrotoluene, TNT)当量,建立ABAQUS有限元三维数值模型的方法研究爆炸情况下隧道的结构响应及U形槽防护有效性。结果表明:在爆炸冲击作用下,隧道出现较严重拉伸损伤,在隧道上部圆拱部分出现较大位移变形,且已超出工程容许标准;爆源上部土体抛掷范围较大,位移云图分层明显;设立U形槽防护之后,隧道基本无塑性损伤,结构变形程度明显减小;U形槽阻碍了爆炸波在土体中传播,上部土体抛掷范围主要集中在U形槽内上方区域,且隧道上部土体位移情况有所改善。可见U形槽的设立在天然气爆炸时可以对隧道起到有效的防护作用,数值模拟结果可为类似工程案例提供参考。 展开更多
关键词 天然气爆炸 隧道 u形槽防护 数值试验 ABAQuS
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U-model Enhanced Dynamic Control of a Heavy Oil Pyrolysis/Cracking Furnace 被引量:1
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作者 Quanmin Zhu Dongya Zhao +1 位作者 Shuzhan Zhang Pritesh Narayan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第2期577-586,共10页
This paper proposes a case study in the control of a heavy oil pyrolysis/cracking furnace with a newly extended U-model based pole placement controller(U-PPC). The major work of the paper includes: 1) establishing a c... This paper proposes a case study in the control of a heavy oil pyrolysis/cracking furnace with a newly extended U-model based pole placement controller(U-PPC). The major work of the paper includes: 1) establishing a control oriented nonlinear dynamic model with Naphtha cracking and thermal dynamics; 2) analysing a U-model(i.e., control oriented prototype) representation of various popular process model sets; 3)designing the new U-PPC to enhance the control performance in pole placement and stabilisation; 4) taking computational bench tests to demonstrate the control system design and performance with a user-friendly step by step procedure. 展开更多
关键词 Index Terms-Computational experiments heavy oil crackingfurnace Kumar molecular dynamics model for Naphtha crack-ing pole placement controller stabilising controller u-model u-model enhanced controller design.
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SECU-Net:一种结合SE和CRF的皮肤病图像分割网络 被引量:3
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作者 陈旋 蔡宇佳 +1 位作者 冉文兵 张利 《智能计算机与应用》 2022年第11期71-77,86,共8页
皮肤癌是一种广泛的、可能致命的疾病。针对皮肤病病灶与背景对比度低、面积和形状变化大等特点,本文提出一种新的皮肤病病灶分割模型(SECU-Net),该模型结合“挤压和激励”机制(Squeeze and Excitation,SE)并引入条件随机场(Conditional... 皮肤癌是一种广泛的、可能致命的疾病。针对皮肤病病灶与背景对比度低、面积和形状变化大等特点,本文提出一种新的皮肤病病灶分割模型(SECU-Net),该模型结合“挤压和激励”机制(Squeeze and Excitation,SE)并引入条件随机场(Conditional Random Fields,CRF)做分割后处理,是一种将概率图形模型纳入神经网络的深度学习分割框架。SECU-Net通过SE模块建模通道之间的相互依赖性,自适应地重新校准通道特性响应。同时,CRF作为U-Net网络中端到端的可训练层,通过对相邻像素进行建模,使得相同属性的像素最大概率分配到相同的标签,产生与图像视觉特征一致的结构化输出。本文通过在具有挑战的ISIC2017皮肤病数据集上进行测试,实验结果表明,SECU-Net与其它医学图像分割模型相比,有更好的效果。 展开更多
关键词 深度学习 皮肤病图像分割 u-Net se CRF
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超频很简单:映泰Tforce4 U SE主板
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《微型计算机》 北大核心 2006年第16期81-81,共1页
为了纪念成立20周年,映泰推出了纪念版TForce4 U SE主板。作为T系列主板,该主板更加注重超频性能,做工和用料得到了加强。在规格上,它与之前上市的DFI VENUS主板很相似。
关键词 超频性能 主板 VENuS DFI 映泰Tforce4 u se
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SE2571U:前端Wi-Fi/蓝牙模块
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《世界电子元器件》 2009年第8期40-40,共1页
SiGe半导体公司现已扩展其Wi-Fi产品系列,推出SE2571U前端模块,面向包括手机、游戏、数码相机和个人媒体播放器(PMP)的嵌入式应用。SE2571U专为应对OEM厂商面临的特定挑战而设计,其特点包括实现电池直接供电运作、提升性能,并满... SiGe半导体公司现已扩展其Wi-Fi产品系列,推出SE2571U前端模块,面向包括手机、游戏、数码相机和个人媒体播放器(PMP)的嵌入式应用。SE2571U专为应对OEM厂商面临的特定挑战而设计,其特点包括实现电池直接供电运作、提升性能,并满足消费者对便携设备内建通用移动通信系统(UMTS)连线能力的需求。 展开更多
关键词 se2571u 蓝牙模块 WI-FI 连线能力
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多尺度注意力融合与视觉Transformer方法优化的电阻抗层析成像深度学习方法
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作者 王琦 张涛 +2 位作者 徐超炜 卢梦凡 王子辰 《仪器仪表学报》 EI CAS CSCD 北大核心 2024年第7期52-63,共12页
电阻抗层析成像(EIT)具有显著的可视化和非侵入性等特点,在工业和生物医学工程领域展现了其广阔的应用潜力。由于其逆问题存在高度非线性和病态性特点,导致了数值成像方法在空间分辨率上的局限性,尤其是在多相介质分布情况下,现有EIT技... 电阻抗层析成像(EIT)具有显著的可视化和非侵入性等特点,在工业和生物医学工程领域展现了其广阔的应用潜力。由于其逆问题存在高度非线性和病态性特点,导致了数值成像方法在空间分辨率上的局限性,尤其是在多相介质分布情况下,现有EIT技术在成像过程中出现边界失真和电导率误差,从而影响最终的成像精度。本文提出了一种基于卷积注意力机制的U型深度成像方法——MAT-UNet,将卷积块注意力模块(CBAM)与U-Net结构相结合,在特征提取与融合过程中嵌入卷积块注意力模块,以增强模型的注意力定向和特征表征能力,同时跳跃连接引入了压缩-激励(SE)注意力机制与视觉Transformer(ViT)来优化全局特征的学习,使用多头交叉注意力模块(MHCA)实现编码器与解码器的多尺度信息融合。MAT-UNet通过大量的仿真数据训练获得最优模型参数,并在多样化复杂形状和肺部仿真模型进行了实验验证。定量评估指标表明,该方法在重建图像中的均方根误差(RMSE)结果为2.3156,结构相似性指数(SSIM)结果为0.9437,可视化结果与真实分布和边界具有很好的一致性。实验结果表明,本文提出的MAT-UNet模型展现出良好的鲁棒性和泛化能力,相较于传统的单一卷积结构,集成Transformer结构提供了更精准的EIT图像重建效果,在无损测量与检测应用中存在很大的潜力和价值。 展开更多
关键词 电阻抗层析成像 卷积注意力机制 se-ViT连接 多头交叉注意力模块 u型卷积网络 无损测量
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