检索结果-南通市图书馆

Comparative Assessment of Impacts of Future Climate Change on Runoff in Upper Daqinghe Basin,China

Chinese Geographical Science 2024年第3期34卷 564-578页

作者： INGABIRE Romaine CHANG Yuru LIU Xia CAO Bo UMUGWANEZA Adeline shen yanjun Key Laboratory of Agricultural Water Resources Hebei-Key Laboratory of Water Saving AgricultureCenter for Agricultural Re-sources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050022China Uni-versity of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Desert and Oasis Ecology Xinjiang Insti-tute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China

Assessing runoff changes is of great importance especially its responses to the projected future climate change on local scale basins because such analyses are generally done on global and regional scales which may lead to generalized conclusions rather than specific ones.Climate change affected the runoff variation in the past in the upper Daqinghe Basin,however,the climate was mainly considered uncertain and still needs further studies,especially its future impacts on runoff for better water resources management and planning.Integrated with a set of climate simulations,a daily conceptual hydrological model(MIKE11-NAM)was applied to assess the impact of climate change on runoff conditions in the Daomaguan,Fuping and Zijingguan basins in the upper Daqinghe Basin.Historical hydrological data(2008–2017)were used to evaluate the applicability of the MIKE11-NAM model.After bias correction,future projected climate change and its impacts on runoff(2025–2054)were analysed and compared to the baseline period(1985–2014)under three shared social economic pathways(SSP1-2.6,SSP2-4.5,and SSP5-8.5)scenarios from Coupled Model Intercomparison Project Phase 6(CMIP6)simulations.The MIKE-11 NAM model was applicable in all three Basins,with both R^(2)and Nash-Sutcliffe Efficiency coefficients greater than 0.6 at daily scale for both calibration(2009–2011)and validation(2012–2017)periods,respectively.Although uncertainties remain,temperature and precipitation are projected to increase compared to the baseline where higher increases in precipitation and temperature are projected to occur under SSP2-4.5 and SSP5-8.5 scenarios,respectively in all the basins.Precipitation changes will range between 12%–19%whereas temperature change will be 2.0℃–2.5℃ under the SSP2-4.5 and SSP5-8.5 scenarios,respectively.In addition,higher warming is projected to occur in colder months than in warmer months.Overall,the runoff of these three basins is projected to respond to projected climate changes differently because runoff is projected to only increas

关键词： runoff climate change MIKE11-NAM model Coupled Model Intercomparison Project Phase 6(CMIP6) upper Daqinghe Basin,China

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Real-time UWOC miniaturized system based on FPGA and LED arrays and its application in MIMO

引用

Chinese Optics Letters 2024年第2期22卷 70-75页

作者：黄安殷洪玺梁彦军王建英沈众卫 School of Information and Communication Engineering Dalian University of TechnologyDalian 116024China

In order to alleviate the impact of turbulence on the performance of underwater wireless optical communication(UWOC)in real time,and achieve high-speed real-time transmission and low cost and miniaturization of equipment,a 2×2 real-time multiple-input and multiple-output(MIMO)high-speed miniaturized UWOC system based on a field-programmable gate array(FPGA)and a high-power light-emitting diode(LED)array is designed in this Letter.In terms of multiplexing gain,the imaging MIMO spatial multiplexing and high-order modulation for the first time are combined and the real-time high-speed transmission of PAM-4 signal based on the LED array light source in 12 m underwater channel at 100 Mbps rate is implemented,which effectively improves the throughput of the UWOC system with a high-power commercial LED light source.In light of diversity gain,the system employs the diversity of repeated coding scheme to receive two identical non-return-to-zero on-off keying(NRZ-OOK)signals,which can compensate the fading or flickering sublinks in real time under the bubble-like simulated turbulence condition,and has high robustness.To our knowledge,this is the first instance of a high rate and long-distance implementation of a turbulence-resistant real-time MIMO miniaturized UWOC system based on FPGA and high-power LED arrays.With spatial diversity or spatial multiplexing capabilities,its low cost,integrity,and high robustness provide the system with important practical prospects.

关键词： underwater wireless optical communication MIMO spatial diversity spatial multiplexing

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Finite-time control of linear parameter-varying systems with norm-bounded exogenous disturbance

引用

控制理论与应用（英文版） 2008年第2期6卷 184-188页

作者： yanjun shen Institute of Nonlinear Complex System China Three Gorges University Yi＇chang Hubei 443002 China

In this paper, a new approach is presented for finite-time control problems for linear systems subject to time-varying parametric uncertainties and exogenous disturbance. The disturbance is assumed to be time varying and bounded. Sufficient conditions are obtained for the existence of a linear parameter-dependent state feedback gain, which can ensure that the closed-loop system is finite-time bounded （FTB）. The conditions can be reduced to feasibility problems involving LMIs. Numerical examples show the validity of the proposed methodology.

关键词： Finite time stability Polytopic system LMI Norm-bounded exogenous disturbance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Molecular phylogeny and divergence time estimates using the mitochondrial genome for the hadal snailfish from the Mariana trench

引用

Science Bulletin 2017年第16期62卷 1106-1108页

作者： yanjun shen Wei Dai Zhaoming Gao Guoyong Yan Xiaoni Gan Shunping He The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of Sciences Beijing 100039China Institute of Deep-sea Science and Engineering Chinese Academy of SciencesSanya 572000China

Snailfishes are an important component of the hadal fish fauna[1].Based on osteological and other morphological characters,Kido[2]recognized the Cyclopteridae as a sister group to the Liparidae and the superfamily Cot... 详细信息

关键词：狮子鱼分子系统发育马里亚纳海沟线粒体基因组时间估计超深分化分子数据

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Enlarged fins of Tibetan catfish provide new evidence of adaptation to high plateau

引用

Science China(Life Sciences) 2023年第7期66卷 1554-1568页

作者： Liandong Yang Ning Sun Honghui Zeng Ying Wang Wenjun Chen Zufa Ding Yang Liu Jing Wang Minghui Meng yanjun shen Jingliang Kang Xiuhui Ma Wenqi Lv Juan Chen Axel Meyer Baocheng Guo Shunping He State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan430072China Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing100101China Academy of Plateau Science and Sustainability Qinghai Normal UniversityXining810016China Hubei Engineering Research Center for Protection and Utilization of Special Biological Resources in the Hanjiang River Basin School of Life SciencesJianghan UniversityWuhan430056China State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunming650223China University of Chinese Academy of Sciences Beijing100049China Department of Biology University of Konstanz78457KonstanzGermany Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunming650223China

The uplift of the Tibetan Plateau significantly altered the geomorphology and climate of the Euroasia by creating large mountains and rivers.Fishes are more likely to be affected relative to other organisms,as they are largely restricted to river systems.Faced with the rapidly flowing water in the Tibetan Plateau,a group of catfish has evolved greatly enlarged pectoral fins with more numbers of fin-rays to form an adhesive apparatus.However,the genetic basis of these adaptations in Tibetan catfishes remains elusive.In this study,we performed comparative genomic analyses based on the chromosome-level genome of Glyptosternum maculatum in family Sisoridae and detected some proteins with conspicuously high evolutionary rates in particular in genes involved in skeleton development,energy metabolism,and hypoxia response.We found that the hoxd12a gene evolved faster and a loss-of-function assay of hoxd12a supports a potential role for this gene in shaping the enlarged fins of these Tibetan catfishes.Other genes with amino acid replacements and signatures of positive selection included proteins involved in low temperature(TRMU)and hypoxia(VHL)responses.Functional assays reveal that the G.maculatum TRMU allele generates more mitochondrial ATP than the ancestral allele found in low-altitude fishes.Functional assays of VHL alleles suggest that the G.maculatum allele has lower transactivation activity than the low-altitude forms.These findings provide a window into the genomic underpinnings of physiological adaptations that permit G.maculatum to survive in the harsh environment of the Tibetan Himalayas that mirror those that are convergently found in other vertebrates such as humans.

关键词： Glyptosternum maculatum enlarged fins adaptation Tibetan Plateau

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

小浪底水库运用以来黄河下游时空冲淤规律与模拟

引用

Journal of Geographical Sciences 2024年第3期34卷 591-609页

作者：沈逸吴保生王彦君覃超郑珊 State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing100084China Key Laboratory of Hydrosphere Sciences of the Ministry of Water Resources Tsinghua UniversityBeijing100084China Department of Hydraulic Engineering Tsinghua UniversityBeijing100084China Key Laboratory of River Regulation and Flood Control of Ministry of Water Resources Yangtze River Scientific Research InstituteWuhan430010China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China

This study focuses on the Lower Yellow River(LYR),which has experienced continuous erosion since the operation of Xiaolangdi Reservoir in 1999,and its spatiotemporal variation process is complex.Based on the single-step mode of the Delayed Response Model(DRM),we proposed a calculation method for simulating the accumulated erosion and deposition volume in the LYR.The coefficient of determination R^(2)between the calculated and measured values from 2000 to 2020 is 0.99.Currently,the LYR is undergoing continuous erosion,however the erosion rate is gradually slowing down,and the difference between the equilibrium and calculated values of accumulated erosion and deposition volume gradually decreases,which means riverbed erosion has a tendency towards equilibrium.Additionally,we derive a formula to simulate the spatial distribution of the main channel accumulated erosion volume per unit river length in the LYR based on the non-equilibrium suspended sediment transport equation.The coefficient of determination R^(2)between the fitted values and measured values from 2003 to 2015 is approximately 0.98-0.99,with a relative error of approximately 6.2%.The findings in this research suggest that under the current background of decreasing sediment inflow and continuous erosion in the LYR,it takes approximately 3.0 years for the riverbed to achieve half of the erosion and deposition adjustment and approximately 13.0 years to achieve 95%of the adjustment.Moreover,the spatial distribution of accumulated main channel erosion volume in the LYR tends to become uniform with the continuous development of erosion.These results could provide a valuable reference for analysing the complex spatiotemporal variation process in the LYR.

关键词： Lower Yellow River erosion and deposition adjustment Delayed Response Model non-equilibrium sediment transport equation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

An improved approach to H-two control withregional stability constraints

引用

控制理论与应用（英文版） 2007年第4期5卷 380-384页

作者： yanjun shen Tingsong DU Institute of Nonlinear Complex System Three Gorges University Yichang Hubei 443002 China College of Science Three Gorges University Yichang Hubei 443002 China

This paper presents an improved method for H-two control with regional stability constraints for the closedloop system. The controller is given by the convex combination of a set of fixed gains. Both continuous and discrete-time systems in a known polytopic domain are investigated. New LMI-based sufficient conditions for the existence of parameterdependent Lyapunov functions are proposed. Numerical examples are given to show the proposed conditions provide useful and less conservative results for the problems of H-two control with regional stability constraints.

关键词： H2 control Regional stability constraints Polytopic domains LMI

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

气候变化对中国东北三省主要粮食作物影响研究综述

引用

中国生态农业学报（中英文） 2024年第6期32卷 970-985页

作者：于水张晓龙王妍沈彦军中国科学院遗传与发育生物学研究所农业资源研究中心/中国科学院农业水资源重点实验室/河北省节水农业重点实验室石家庄050022 中国科学院大学北京100049 河北师范大学地理科学学院/河北省环境演变与生态建设实验室石家庄050024

全球气候变化已经成为事实,并且导致全球粮食危机和饥饿风险增加。东北三省作为我国主要的粮食生产基地,对气候变化十分敏感。本文梳理了当前及未来气候变化对东北三省玉米、水稻和大豆生产影响的相关研究,概括了当前主要研究方法、东... 详细信息

全球气候变化已经成为事实,并且导致全球粮食危机和饥饿风险增加。东北三省作为我国主要的粮食生产基地,对气候变化十分敏感。本文梳理了当前及未来气候变化对东北三省玉米、水稻和大豆生产影响的相关研究,概括了当前主要研究方法、东北三省主要作物对气候变化的响应以及应对措施,并进一步评述了当前主要研究方法和研究领域的不足:1)研究气候变化和极端气候事件对作物生长发育和产量影响的主要方法包括田间试验法、统计分析法以及作物模型法,其中田间试验法结果最直观,统计分析法可操作强、应用范围最广,作物模型法机理性强。2)东北三省气候变化明显,并且随着气候变化,干旱逐渐取代低温冷害成为当地主要灾害。3)气候变化对东北三省作物生产整体是有利的。气候变暖改善了东北三省热量资源,不仅使作物种植区域逐渐北移,作物品种也逐渐从早中熟向中晚熟转变。4)随着气候变暖不断加剧,未来东北地区作物应选择耐高温、抗旱和抗寒等抗逆性强的品种;加强农田水利设施建设,增强应对干旱洪涝灾害的能力;采用新的农业管理措施,保护土壤健康以及粮食生产安全。5)未来需要加强对CO_(2)补偿效应以及病虫害等的研究,加强对作物模型的完善,以更好地应对气候变化对粮食安全的不利影响。

关键词：东北三省气候变化气象灾害主要粮食作物热量资源 CO_(2)补偿效应

来源：

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Sandstone-concrete interface transition zone (ITZ) damage and debonding micromechanisms under freeze-thaw

引用

Research in Cold and Arid Regions 2021年第2期13卷 133-149页

作者： yanjun shen Huan Zhang JinYuan Zhang HongWei Yang Xu Wang Jia Pan School of Geology and Environment Xi'an University of Science and TechnologyXi'anShaanxi 710054China Geological Research Institute for Coal Green Mining Xi'an University of Science and TechnologyXi'anShaanxi 710054China Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation Xi'anShaanxi 710054China School of Architecture and Civil Engineering Xi'an University of Science and TechnologyXi'anShaanxi 710054China

The sufficient bond between concrete and rock is an important prerequisite to ensure the effect of shotcrete support. However, in cold regions engineering protection system, the bond condition of rock and concrete surface is easily affected by freeze-thaw cycles, resulting in interface damage, debonding and even supporting failure. Understanding the micromechanisms of the damage and debonding of the rock-concrete interface is essential for improving the interface protection.Therefore, the micromorphology, micromechanical properties, and microdebonding evolution of the sandstone-concrete interface transition zone(ITZ) under varying freeze-thaw cycles(0, 5, 10, 15, 20) were studied using scanning electron microscope, stereoscopic microscope, and nano-indentation. Furthermore, the distribution range and evolution process of ITZ affected by freeze-thaw cycles were defined. Major findings of this study are as follows:(1) The microdamage evolution law of the ITZ under increasing freeze-thaw cycles is clarified, and the relationship between the number of cracks in the ITZ and freeze-thaw cycles is established;(2) As the number of freeze-thaw cycles increases, the ITZ's micromechanical strength decreases, and its development width tends to increase;(3) The damage and debonding evolution mechanisms of sandstone-concrete ITZ under freeze-thaw cycles is revealed, and its micromechanical evolution model induced by freeze-thaw cycles is proposed.

关键词： sandstone-concrete interface transition zone(ITZ) freeze-thaw cycles nano-indentation damage and debonding

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Comparison of winter wheat yield sensitivity to climate variables under irrigated and rain-fed conditions

引用

Frontiers of Earth Science 2016年第3期10卷 444-454页

作者： Dengpan XIAO yanjun shen He ZHANG Juana P. MOIWO Yongqing QI Rende WANG Hongwei PEI Yucui ZHANG Huitao shen Key Laboratory for Agricultural Water Resources Hebei Key Laboratory for Agricultural Water-Saving Center for Agricultural Resources Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences Shijiazhuang 050021 China Institute of Geographical Sciences Hebei Academy of Sciences Shijiazhuang 050011 China Institute of Geographical Sciences and Resources Research Chinese Academy of Sciences Beijing 100101 China School of Technology Njala University Njala Sierra Leone

Crop simulation models provide alternative, less time-consuming, and cost-effective means of deter- mining the sensitivity of crop yield to climate change. In this study, two dynamic mechanistic models, CERES （Crop Environment Resource Synthesis） and APSIM （Agricultural Production Systems Simulator）, were used to simulate the yield of wheat （Triticum aestivum L.） under well irrigated （CFG） and rain-fed （YY） conditions in relation to different climate variables in the North China Plain （NCP）. The study tested winter wheat yield sensitivity to different levels of temperature, radiation, precipitation, and atmospheric carbon dioxide （COa） concentration under CFG and YY conditions at Luancheng Agro-ecosystem Experimental Stations in the NCR The results from the CERES and APSIM wheat crop models were largely consistent and suggested that changes in climate variables influenced wheat grain yield in the NCR There was also significant variation in the sensitivity of winter wheat yield to climate variables under different water （CFG and YY） conditions. While a temperature increase of 2℃ was the threshold beyond which temperature negatively influenced wheat yield under CFG, a temperature rise exceeding 1℃ decreased winter wheat grain yield under YY. A decrease in solar radiation decreased wheat grain yield under both CFG and YY conditions. Although the sensitivity of winter wheat yield to precipitation was small under the CFG, yield decreased significantly with decreasing precipitation under the rain- fed YY treatment. The results also suggest that wheat yield under CFG linearly increased by ≈ 3.5% per 60 ppm （parts per million） increase in CO2 concentration from 380 to560ppm, and yield under YY increased linearly by ≈ 7.0% for the same increase in CO2 concentration.

关键词： winter wheat yield sensitivity climate vari-ables crop model North China Plain

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：