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Factors affecting post-release survival and dispersal of reintroduced Crested Ibis(Nipponia nippon)in Tongchuan City,China
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作者 Min Li Yilamujiang Tuohetahong +5 位作者 Feng Lin Rong Dong Huaqiang Wang Xiaoman Wu Xinping Ye Xiaoping Yu 《Avian Research》 SCIE CSCD 2022年第3期356-361,共6页
Reintroduction has become a common conservation management tool to restore endangered species in their historical range.However,many attempts have failed to establish self-sustaining populations in the wild.The succes... Reintroduction has become a common conservation management tool to restore endangered species in their historical range.However,many attempts have failed to establish self-sustaining populations in the wild.The success of reintroductions could be improved by varying release strategies.Therefore,it is vital to determine the factors influencing reintroduction outcomes.To better understand the post-release settlement and to optimize the release strategy of the Crested Ibis(Nipponia nippon),we quantified the effects of age,sex,acclimation duration,and the timing of release events on post-release survival and dispersal distance for the released Crested Ibis in Tongchuan City,Shaanxi Province,using a generalized linear mixed effect modeling approach.Our results indicate that 40–56.3%of the released individuals survived the first year following release.Mortality was attributable to flight collisions,starvation,disease,and unknown reasons.The post-release survival probability of ibises showed a negative association with age(estimate=-0.186;95%CI:-0.350 to-0.022;P=0.026),and post-release dispersal distance was affected by the timing of release event(estimate=0.718;95%CI:0.025 to1.253;P=0.042).However,sex and acclimation period duration did not cause detectable differences in postrelease survival probability and dispersal distance.Based on our results,optimal release strategies for establishing a reintroduced population of the Crested Ibis include:(1)release of sub-adults biased and sex ratio balanced initial groups;(2)release during the non-breeding season;and(3)food supplementation immediately after release. 展开更多
关键词 crested ibis Post-release dispersal Release strategy REINTRODUCTION Survival probability
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Post-fledging dispersal and habitat use of a reintroduced population of the Crested Ibis (Nipponia nippon) 被引量:4
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作者 Zhiping Huo Junfeng Guo +1 位作者 Xia Li Xiaoping Yu 《Chinese Birds》 CSCD 2014年第1期49-57,共9页
Background: Knowledge of dispersal movement of birds and their habitat preference during the post-fledging period is fundamental to the understanding of their ecological and evolutionary processes. The Crested Ibis is... Background: Knowledge of dispersal movement of birds and their habitat preference during the post-fledging period is fundamental to the understanding of their ecological and evolutionary processes. The Crested Ibis is now being reintroduced to protected sites within its historical range, with the goal of establishing a self-sustaining population that may eventually qualify the species for delisting.Methods: We carried out an ecological study of post-fledging dispersal and habitat use of a reintroduced population of the Crested Ibis(Nipponia nippon) from 2008 to 2012 in Ningshan County, China, by using banding and radio-telemetry methods.Results: In about two weeks(an average of 14.3 days) after fledging, the activities of the fledglings were concentrated in a range of about 100 m around their natal sites, such as the oak-pine forest patches at the edge of open habitats.During this period, fledglings were still partially dependent upon parental care and fed typically on a daily basis.Siblings increasingly became independent by mid-August and then gradually moved away from their natal sites to post-fledging dispersal locations. During the period of the post-fledging dispersal process, most juveniles moving southwest were concentrated at the mean direction(μ = 254.6°, ? = 70.5°) with a mean dispersal distance of 5.1 km.It took an average of 56.4 days to disperse from the natal territory to the first wintering area. Also, forging habitats for juvenile ibis varied with time and local conditions. For example, paddy fields were used most frequently among all habitat types, while shallow rivers just from August to October. Masson pine(Pinus massoniana) was often regarded as the roosting tree species preferred by the Crested Ibis, with the highest utilization rate among all the roosting habitat types. The juveniles of the wild population dispersed four times as far as that of the reintroduced population, but the overall pattern of post-fledging dispersal is similar for the reintroduced and wild populations.Conclusions: Our results are very useful for us to predict the distance and direction of dispersal under various landscape conditions in other released sites. The project is a good example for reintroducing endangered species to their former ranges, and will be valuable for the protection of reintroduced populations of this critically and other endangered species. 展开更多
关键词 crested ibis Ningshan County Post-fledging dispersal HABITAT use Reintroduced POPULATION
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Effects of breeding success,age and sex on breeding dispersal of a reintroduced population of the Crested Ibis(Nipponia nippon)in Ningshan County,China 被引量:2
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作者 Rong Dong Xinping Ye +4 位作者 Lin Zhong Xia Li Min Li Huaqiang Wang Xiaoping Yu 《Avian Research》 CSCD 2018年第4期314-320,共7页
Background: Breeding dispersal is an important ecological process that affects species' population dynamics and colonization of new suitable areas. Knowledge of the causes and consequences of breeding dispersal is... Background: Breeding dispersal is an important ecological process that affects species' population dynamics and colonization of new suitable areas. Knowledge of the causes and consequences of breeding dispersal is fundamental to our understanding of avian ecology and evolution. Although breeding success for a wild and reintroduced population of the Crested Ibis(Nipponia nippon) has been reported, the relationships between individuals' breeding dispersal and their breeding success, age and sex remain unclear.Methods: Ibises' breeding dispersal distance, which is the distance moved by adults between sites of reproduction, was estimated based on the observations of consecutive breeding sites of marked ibis individuals. From observational and capture-recapture data(n as = 102) over 9 years, individuals' breeding dispersal probability in relation to age, sex, and reproductive success wanalyzed via a generalized linear mixed effect modeling approach.Results: Our results show that 55% males and 51% females keep their previous territories following nesting success. Failed breeding attempts increased dispersal probabilities. Both females and males failed in breeding were more likely to disperse with greater distances than successful birds(females: 825 ± 216 m vs 196 ± 101 m, males: 372 Crested Ibis exhibited a female-biased dispersal pattern that the mean dispersal distance± 164 m vs 210 ± 127 m). of females(435 ± 234 m) was much larger than that of males(294 ± 172 m).Conclusion: Our results are fundamental to predict the patterns of breeding dispersal related to reproductive success under different release sites. From the conservation point of view, landscape connectivity between the reintroduced populations should be taken into account in accordance with the distance of breeding dispersal. 展开更多
关键词 BREEDING dispersal BREEDING SUCCESS Generalized linear mixed effect model crested ibis Reintroduced POPULATION
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Sharing and evaluation of a new community co-management model for protecting Crested Ibis:a case study of Crested Ibis National Nature Reserve,China 被引量:5
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作者 WANG Chang-hai WEN Ya-li +2 位作者 LIU Xiao-hai KANG Kai-li LI Bing 《Ecological Economy》 2010年第4期376-386,共11页
The Crested Ibis(Nipponia Nippon) is endemic to Qinling Mountains of China and was once abundant over vast areas of north-east of Asia habitat.During the 20th century,however,the population declined greatly in numbers... The Crested Ibis(Nipponia Nippon) is endemic to Qinling Mountains of China and was once abundant over vast areas of north-east of Asia habitat.During the 20th century,however,the population declined greatly in numbers.Habitat quality used to be the main threat to this species but recent actions by the government and wildlife protection organizations have brought this under control.With the establishment of Crested Ibis Nature Reserve in China,conflicts between socio-economic development and Crested Ibis conservation have become more acute.How do we deal with the relation between Crested Ibis conservation and community development? In this study,the Crested Ibis Nature Reserve co-management model namely "companies + farmers + Nature Reserve" model is proposed and evaluated with demonstration investigation methods,including continuous six-year fixed-site socio-economic development data of surrounding community,company sales revenue data and monitored data of Crested Ibis Nature Reserve.The results show that farmers' income and conservation awareness increased greatly from 2003 to 2008;company sales revenue has increased by about 20% annually in the recent years;management level has noticeably improved in Nature Reserve,the scope of Crested Ibis habitat has expanded 50 hm2;chemical composition of habitat reduced year after year;and the number of Crested Ibis had been growing annually.At the end,the success of the model is evaluated,and problems in implementation of the model are discussed from the following aspects:management system,co-management concept,economic base of partners,marketing mechanism,technical capacity and so on. 展开更多
关键词 国家级自然保护区 社区管理 合作伙伴 朱鹮 模式评价 中国 社会经济发展 共享
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BACK FROM THE BRINK:Once thought extinct,the population of the crested ibis is growing after four decades of conservation efforts in China
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作者 Zuo Lin 《China Report ASEAN》 2020年第8期37-39,共3页
About 200 kilometers south of Xi’an,capital of southwest China’s Shaanxi Province,along the H anjiang River in the Hanzhong Basin,is Yangxian County.Abundant rainfall brings lush vegetation by early summer,making th... About 200 kilometers south of Xi’an,capital of southwest China’s Shaanxi Province,along the H anjiang River in the Hanzhong Basin,is Yangxian County.Abundant rainfall brings lush vegetation by early summer,making the area attractive to the crested ibis(Nipponia nippon),a medium-sized,white-plumaged wading bird with bright red on its face,legs,and tip of bill. 展开更多
关键词 CREST sized ATTRACTIVE
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A Novel Method for Forecasting Freak Wave Occurrence in A Short Crested Coastal Sea
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作者 WANG Ying-guang 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期104-116,共13页
In order to forecast the distribution of crest amplitudes and the occurrence of freak waves in a short crested coastal sea,a novel transformed linear simulation method is initially proposed in this paper.A Hermite tra... In order to forecast the distribution of crest amplitudes and the occurrence of freak waves in a short crested coastal sea,a novel transformed linear simulation method is initially proposed in this paper.A Hermite transformation model expressed as a monotonic cubic polynomial serves as the foundation for the novel simulation technique.The wave crest amplitude exceedance probabilities of two sea states-one with a directional wave spectrum based on the measured wave elevation data at the Yura coast and the other with a typical directional JONSWAP wave spectrum-have been predicted using the novel simulation method that has been proposed.The likelihood that a particular critical wave crest amplitude will be exceeded is directly correlated with the probability that freak waves will occur.It is shown that the novel simulation approach suggested can provide predictions that are more precise than those obtained from the Rayleigh crest amplitude distribution model,the Jahns and Wheeler crest amplitude distribution model,or the conventional linear simulation method.This study also demonstrated that the nonlinear simulation method is less effective than the novel simulation method in terms of efficiency. 展开更多
关键词 wave crest amplitude freak waves short crested sea transformed linear simulation
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串行链路IBIS-AMI模型信号完整性分析及优化
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作者 杨云普 王青 曾燕萍 《无线电工程》 2024年第4期882-891,共10页
为解决高速串行链路通信时由于均衡器未精细配置导致的信号完整性问题,通过研究IBIS-AMI模型均衡结构对信号完整性的影响,使用田口试验法建立仿真试验,实现各均衡参数优化,解决了均衡器参数需要精细配置的问题。建立并分析一阶线性模型... 为解决高速串行链路通信时由于均衡器未精细配置导致的信号完整性问题,通过研究IBIS-AMI模型均衡结构对信号完整性的影响,使用田口试验法建立仿真试验,实现各均衡参数优化,解决了均衡器参数需要精细配置的问题。建立并分析一阶线性模型,对最佳参数组合下的眼图做出预测,并将仿真值与预测值进行对比,验证了最佳参数组合的准确性。在最佳均衡参数下,发射端与接收端得到的预测值和仿真值最大偏差不超过6%,证明了该最佳参数组合是准确的。眼图扩张程度提升了25%,信号质量明显变好,为系统驱动程序设置与信号完整性研究提供了较好的指导与参考。 展开更多
关键词 信号完整性 ibis-AMI 田口试验 高速串行链路 眼图
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Sex-related gene and sex identification of Crested Ibis Nipponia nippon (Ciconiifor-mes: Threskiornithidae) 被引量:2
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作者 LI Ming DING Changqing +3 位作者 WEI Fuwen MENG Shijie XI Yongmei LU Baozhong 《Chinese Science Bulletin》 SCIE EI CAS 2001年第8期669-671,共3页
The Crested Ibis (Nipponia nippon) is a critical endangered species of the world. At present, a reintroduction program will be conducted to save this species essentially. However, because the Crested Ibise is a sexual... The Crested Ibis (Nipponia nippon) is a critical endangered species of the world. At present, a reintroduction program will be conducted to save this species essentially. However, because the Crested Ibise is a sexual alike bird, it is very difficult to identify the sex from the morphological character. In order to identify the sex easily and select the right individuals for captive breeding and reintroduction, the sex related gene on W chromosome was amplified and the sex of three Crested Ibises were also identified in the present study. The 262bp fragment was also sequenced, and we found that there were 13 different nucleotide sites with 2.25 of transition/transversion based on the comparison with that of the Oriental White Stork. The sequence will also provide a theoretic base for further designing specific primer for sex related gene in the Crested Ibis. 展开更多
关键词 crested ibis Nipponia NIPPON SEX-RELATED GENE SEX identification.
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基于IBIS模型的FPGA总剂量效应建模方法
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作者 张晓鹏 刘锦辉 +3 位作者 梁博 谭雯丹 张馨丹 刘刚 《单片机与嵌入式系统应用》 2023年第7期44-48,共5页
提出了一种基于输入/输出缓冲区信息规范的FPGA的TID效应建模方法。将FPGA电路结构划分为3部分:输入缓冲区、输出缓冲区、逻辑功能区。缓冲区模型基于IBIS模型使用VHDLAMS建立,功能区模型基于特定需求采用VHDL建立。针对基于IBIS模型的... 提出了一种基于输入/输出缓冲区信息规范的FPGA的TID效应建模方法。将FPGA电路结构划分为3部分:输入缓冲区、输出缓冲区、逻辑功能区。缓冲区模型基于IBIS模型使用VHDLAMS建立,功能区模型基于特定需求采用VHDL建立。针对基于IBIS模型的建模需要,测量了FPGA在0 krad(Si)、820 krad(Si)和2.52 Mrad(Si)的IBIS模型和端口电平数据。通过对比仿真结果和试验结果,验证了所建模型能够反映FPGA受TID效应影响后的电平转换时间变长现象,结果误差在30%以内。所提建模方法为评估数字器件的TID效应提供了模型支撑,对数字系统抗辐射加固具有一定参考意义。 展开更多
关键词 FPGA 总剂量效应 ibis模型 混合信号模型 电平转换时间
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IBIS-S干涉雷达技术在特大跨径桥梁动态形变规律监测中的应用
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作者 张国卿 王兵 +3 位作者 刘志勇 刘胜震 陈景涛 张国建 《北京测绘》 2023年第12期1585-1589,共5页
特大跨径桥梁的建设技术趋于成熟,但是对于特大跨径桥梁的变形规律却有待研究。本文利用干涉测量雷达技术对特大跨径桥梁进行监测,并分析其变形规律。实验以济南黄河凤凰大桥为例,在大桥南岸架设仪器呈水平5°的夹角,并采用20 Hz采... 特大跨径桥梁的建设技术趋于成熟,但是对于特大跨径桥梁的变形规律却有待研究。本文利用干涉测量雷达技术对特大跨径桥梁进行监测,并分析其变形规律。实验以济南黄河凤凰大桥为例,在大桥南岸架设仪器呈水平5°的夹角,并采用20 Hz采样频率对桥梁的挠度进行监测。实验结果表明:最大形变在监测点位500 m处(跨中),竖向挠度达到了218.67 mm,并呈现出主跨中心形变较大,塔桥位置形变较小的特性,为以后特大跨径桥梁监测提供了思路。 展开更多
关键词 雷达干涉测量 安全监测 特大跨径桥梁 挠度变形 动态监测
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神经嵴发育异常相关眼病
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作者 李晶 马忠旭 《国际眼科杂志》 2024年第1期53-57,共5页
神经嵴是一个动态的胚胎干细胞群体,在眼部发育中起着关键作用。神经嵴与周围的神经外胚层、表面外胚层和中胚层相互作用,发育成眼球及其附属器的多种组织结构,包括角膜基质及内皮、小梁网、虹膜基质、睫状肌、玻璃体和脉络膜血管、M... 神经嵴是一个动态的胚胎干细胞群体,在眼部发育中起着关键作用。神经嵴与周围的神经外胚层、表面外胚层和中胚层相互作用,发育成眼球及其附属器的多种组织结构,包括角膜基质及内皮、小梁网、虹膜基质、睫状肌、玻璃体和脉络膜血管、Müller细胞等。眼部神经嵴细胞迁移和发育异常会引起一系列复杂的眼部疾病,包括影响眼前段的疾病,如Axenfeld-Rieger综合征、Peters异常、无虹膜、原发性先天性青光眼和指甲-髌骨综合征,以及影响眼后段的缺陷性疾病,如CHARGE综合征和鳃-眼-面综合征,此外还有一些罕见的神经嵴疾病的眼部异常,如Waardenburg综合征、Treacher-Collins综合征和Char综合征等。在这里我们将神经嵴细胞发育异常导致的眼部相关疾病做一综述,探讨与神经嵴迁移和发育相关的基因,以及这些基因的突变和缺陷如何导致眼部疾病。 展开更多
关键词 神经嵴 神经嵴发育异常相关眼病 基因突变
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基于IBIS模型的1960-2006年中国陆地生态系统碳收支格局研究 被引量:31
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作者 杨延征 马元丹 +3 位作者 江洪 朱求安 刘金勋 彭长辉 《生态学报》 CAS CSCD 北大核心 2016年第13期3911-3922,共12页
定量评估区域陆地生态系统碳收支是生态系统与全球变化科学研究的重要科学问题之一。利用集成生物圈模型(IBIS)对中国陆地生态系统历史时期(1960—2006年)气候及CO2浓度变化条件下碳收支时空变异特征和发展趋势进行了模拟分析。结果表明... 定量评估区域陆地生态系统碳收支是生态系统与全球变化科学研究的重要科学问题之一。利用集成生物圈模型(IBIS)对中国陆地生态系统历史时期(1960—2006年)气候及CO2浓度变化条件下碳收支时空变异特征和发展趋势进行了模拟分析。结果表明,1960—2006年间,中国陆地生态系统净初级生产力(NPP)总量水平约为2.46 Gt C/a,总体呈上升趋势,在东南及西南地区最高,其次是长白山及大小兴安岭地区,西北内陆地区的净初级生产力水平最低;1960—2006年间,中国陆地生态系统净生态系统生产力(NEP)总量水平约为0.11 Gt C/a,总体呈上升趋势,绝大部分区域表现为碳汇效应,大兴安岭、小兴安岭、长白山、东南地区及西南部分地区碳汇效应较强,西北内陆区表现出弱碳源效应,温带湿润区、高原温带区和高原寒带区碳汇效应呈显著上升趋势;中国11个气候区,NPP与降水均为正相关,除了中温带湿润区、寒温带湿润区、高原温带和高原寒带外,降水是限制植被生长的主要因子。除了高原寒带外,NEP同样表现出与降水的更强相关性,与气温的相关性较弱。经验证,IBIS模型对于中国陆地生态系统碳收支的模拟结果合理,可以为科学预测生态系统的固碳潜力和制定区域碳管理政策提供科学依据。 展开更多
关键词 陆地生态系统 碳收支 NPP NEP ibis模型 中国
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基于IBIS模型的1955~2006年中国土壤温度模拟及时空演变分析 被引量:8
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作者 朱求安 江洪 +2 位作者 刘金勋 方秀琴 余树全 《地理科学》 CSCD 北大核心 2010年第3期355-362,共8页
基于IBIS模型对中国1955~2006年的土壤上层1m的年平均与月平均土壤温度进行模拟,并利用全国气象站点土壤温度观测数据对模拟结果进行验证,结果显示中国南方区的模拟效果优于北方及青藏高原区,春、夏、秋三季模拟效果优于冬季,总体而言... 基于IBIS模型对中国1955~2006年的土壤上层1m的年平均与月平均土壤温度进行模拟,并利用全国气象站点土壤温度观测数据对模拟结果进行验证,结果显示中国南方区的模拟效果优于北方及青藏高原区,春、夏、秋三季模拟效果优于冬季,总体而言取得了较满意的效果。基于模拟结果,利用Mann-Kendall方法对中国1955~2006年年平均和月平均土壤温度进行趋势分析的结果表明,年平均土壤温度,中国北方呈显著上升趋势,南方呈非显著上升趋势,四川盆地、贵州中部、藏东南及天山地区等小部分区域呈现显著或非显著下降趋势;月平均土壤温度,北方基本保持显著上升趋势,南方地区7~9月份总体呈现出下降的趋势,8月份最为显著。 展开更多
关键词 土壤温度 ibis模型 MANN-KENDALL 趋势分析 中国
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IBIS模拟东北东部森林NPP主要影响因子的敏感性 被引量:14
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作者 刘曦 国庆喜 刘经伟 《生态学报》 CAS CSCD 北大核心 2011年第7期1772-1782,共11页
IBIS(Integrated Biosphere Simulator)模型是生态系统过程模型,运行过程需要大量输入变量,包括植被、土壤和气候等。基于2004-2005年帽儿山不同植被类型净初级生产力(NPP)实测数据,修改了模型内部参数,使其更适合于我国东北东部地区NP... IBIS(Integrated Biosphere Simulator)模型是生态系统过程模型,运行过程需要大量输入变量,包括植被、土壤和气候等。基于2004-2005年帽儿山不同植被类型净初级生产力(NPP)实测数据,修改了模型内部参数,使其更适合于我国东北东部地区NPP模拟。还展开了NPP对模型主要输入变量变化敏感程度的研究。结果表明:IBIS模型的输入变量中,叶面积指数(LAI)对模拟结果影响较大,且NPP对LAI增加/降低5%敏感性最强;在气候情景范围内,仅考虑单一气象因子作用,NPP对温度变化敏感性最小;对降水量反应敏感,并随降水量增多而升高。 展开更多
关键词 净初级生产力 ibis模型 敏感性分析 叶面积指数 温度 降水量
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严寒地区拱坝溢流表孔三维有限元数值模拟分析
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作者 王莉艳 《红水河》 2024年第2期32-36,共5页
溢流表孔作为拱坝重要的泄水建筑物,对大坝安全运行具有重要的作用。以某拱坝溢流表孔为例,该表孔地处高纬度严寒地区、结构复杂且地震烈度高,通过三维有限元法对表孔在不同工况下的静、动力应力进行计算分析,根据计算结果,对表孔结构... 溢流表孔作为拱坝重要的泄水建筑物,对大坝安全运行具有重要的作用。以某拱坝溢流表孔为例,该表孔地处高纬度严寒地区、结构复杂且地震烈度高,通过三维有限元法对表孔在不同工况下的静、动力应力进行计算分析,根据计算结果,对表孔结构进行配筋设计,确定受拉钢筋的布置方式及配筋量,使表孔结构钢筋布置满足承载力及正常使用要求。研究结果可为类似工程配筋设计提供参考依据。 展开更多
关键词 溢流表孔 泄水建筑物 三维有限元法 数值模拟 严寒地区
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IBIS-L系统检测方法研究 被引量:4
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作者 邢诚 徐亚明 +1 位作者 周校 王鹏 《工程勘察》 2013年第12期37-40,52,共5页
介绍了基于地基干涉测量技术的微变形监测系统——IBIS-L系统的工作原理及关键技术。根据生产商给定的系统精度标称参数,设计了相应的精度检测方案,通过实验验证了IBIS-L系统对目标物变形量监测所能达到的精度及分辨率。实验表明,IBIS-... 介绍了基于地基干涉测量技术的微变形监测系统——IBIS-L系统的工作原理及关键技术。根据生产商给定的系统精度标称参数,设计了相应的精度检测方案,通过实验验证了IBIS-L系统对目标物变形量监测所能达到的精度及分辨率。实验表明,IBIS-L系统可以实现高精度的目标物微变形监测。 展开更多
关键词 ibis—L 变形监测 干涉测量 精度检测
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基于IBIS模型的高速数字I/O缓冲器的瞬态行为建模 被引量:5
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作者 蔡兴建 毛军发 +1 位作者 陈建华 李征帆 《上海交通大学学报》 EI CAS CSCD 北大核心 2001年第1期5-9,共5页
引入了一种基于最新版本的 IBIS模型给出的信息构造高速数字 I/O缓冲器的瞬态行为模型的方法 .阐述了从 IBIS建模数据中得到这种瞬时状态转换行为模型的推导过程 ,同时获得了建模所需要的充分条件 .与相应的晶体管级模型相比 ,该方法在... 引入了一种基于最新版本的 IBIS模型给出的信息构造高速数字 I/O缓冲器的瞬态行为模型的方法 .阐述了从 IBIS建模数据中得到这种瞬时状态转换行为模型的推导过程 ,同时获得了建模所需要的充分条件 .与相应的晶体管级模型相比 ,该方法在获得了更高仿真精度的同时 ,提高了具有大量同步开关器件芯片互连的仿真速度 .最后 ,为了验证模型的有效性 ,给出了该模型和晶体管级模型 (SPICE模型 ) 展开更多
关键词 数字集成电路 ibis模型 高速数字I/O缓冲器 瞬态行为模型 同步开关器件芯片互连
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IBIS模型验证与东北东部森林NPP季节变化模拟研究 被引量:3
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作者 刘曦 国庆喜 刘经伟 《森林工程》 2010年第4期1-7,10,共8页
IBIS(Integrated Biosphere Simulator)模型是生态系统过程模型,代表着全球碳循环模拟的研究方向。基于2004和2005年帽儿山不同植被类型净初级生产力(NPP)实测数据,修改IBIS模型参数,使其更适合于我国东北东部地区NPP模拟,并从点至面展... IBIS(Integrated Biosphere Simulator)模型是生态系统过程模型,代表着全球碳循环模拟的研究方向。基于2004和2005年帽儿山不同植被类型净初级生产力(NPP)实测数据,修改IBIS模型参数,使其更适合于我国东北东部地区NPP模拟,并从点至面展开区域范围内NPP的模拟。结果如下:IBIS模型能够较好的模拟生长季温度和降水,但对非生长季尤其是初春和冬季温度和降雨(雪)模拟不足,对不同植被类型NPP模拟误差均小于众文献,表明该模型在本区域内的适用性。NPP表现出比较明显的季节变化特征,夏季NPP是全年最高的季节,占全年NPP的53%~70%;NPP最低值出现在冬季,2004年和2005年NPP均以春季变化最剧烈。 展开更多
关键词 ibis 净初级生产力 季节变化
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太湖底栖动物时空分布特征及基于底栖动物完整性指数的水生态健康评价
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作者 陶艳茹 董稳静 +3 位作者 罗明科 李则婵 庞燕 许秋瑾 《环境科学研究》 CAS CSCD 北大核心 2024年第4期752-763,共12页
太湖地处长江三角洲核心区域,面对经济发展,其富营养化威胁到水生态健康.为摸清太湖底栖动物时空分布特征及其水生态健康状况,于2023年枯水期(2月)、平水期(5月)、丰水期(8月),在太湖北部、西部、南部、东部和中部湖区的16个采样点进行... 太湖地处长江三角洲核心区域,面对经济发展,其富营养化威胁到水生态健康.为摸清太湖底栖动物时空分布特征及其水生态健康状况,于2023年枯水期(2月)、平水期(5月)、丰水期(8月),在太湖北部、西部、南部、东部和中部湖区的16个采样点进行水样、底泥及底栖动物的分析鉴定.太湖共采集到1116个底栖动物,包含3门7纲15目18科38种.结果表明:太湖东部湖区底栖动物多样性较好,Shannon-Wiener指数平均值(4.86)和丰富度指数平均值(6.82)明显高于其他湖区,软体动物最多,节肢动物最少;北部湖区的霍甫水丝蚓(Limnodrilus hoffmeistteri)、寡鳃齿吻沙蚕(Nephtys oligobranchia)以及摇蚊科等耐污物种个数显著高于其他湖区,摇蚊类的数量受水期变化的波动较大.太湖丰水期常见种最多,摇蚊类种类和数量明显降低,生物多样性较低.在构建底栖动物完整性指数(B-IBI)体系过程中,选出均匀度指数、丰富度指数、腹足纲相对丰度、耐污类群百分比、生物指数(BI)和粘附者相对丰度6个核心指标,采用三分法对太湖水生态健康结果进行评估.B-IBI值显示,太湖北部湖区的水生态状况相对较差(B-IBI平均值为18),东部湖区水生态较健康(B-IBI平均值为25);平水期的生态状况最好,枯水期次之,丰水期最差,三个时期健康点位占比分别为43.75%、62.50%和25.00%.冗余分析显示,水体和底泥中的氮、磷以及Chl-a是影响B-IBI值的关键因子.研究显示,太湖底栖动物群落和水生态健康状况在东部湖区明显优于其他湖区,西部湖区的水生态健康状况在枯水期和丰水期明显下降,对特定湖区在特定水期加强保护对太湖湖泊环境保护具有重要意义. 展开更多
关键词 太湖 底栖动物 时空分布 B-IBI 健康评价
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IBIS模型在微机系统时钟设计中的应用 被引量:1
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作者 蒋建军 项湜伍 《中北大学学报(自然科学版)》 EI CAS 2006年第4期306-309,共4页
介绍了在移动微机系统设计中引入IB IS(Inpu t/O u tpu t Bu ffer In form ation Spec ification)模型的重要性和必要性,以及IB IS模型在移动微机系统时钟设计中的应用方法,给出了时钟信号仿真的原理与波形.仿真结果表明,IB IS模型在微... 介绍了在移动微机系统设计中引入IB IS(Inpu t/O u tpu t Bu ffer In form ation Spec ification)模型的重要性和必要性,以及IB IS模型在移动微机系统时钟设计中的应用方法,给出了时钟信号仿真的原理与波形.仿真结果表明,IB IS模型在微机系统时钟设计、错误预防中所起的重要作用,可以缩短微机系统设计周期,提高设计的成功率. 展开更多
关键词 ibis模型 高速线路 设计 系统时钟 仿真
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