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REFINEMENTS OF THE NORM OF TWO ORTHOGONAL PROJECTIONS
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作者 Xiaohui LI Meiqi LIU Chunyuan DENG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1229-1243,共15页
In this paper,some refinements of norm equalities and inequalities of combination of two orthogonal projections are established.We use certain norm inequalities for positive contraction operator to establish norm ineq... In this paper,some refinements of norm equalities and inequalities of combination of two orthogonal projections are established.We use certain norm inequalities for positive contraction operator to establish norm inequalities for combination of orthogonal projections on a Hilbert space.Furthermore,we give necessary and sufficient conditions under which the norm of the above combination of o`rthogonal projections attains its optimal value. 展开更多
关键词 NORM orthogonal projection positive operator SPECTRAL block operator valued matrix
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How do lateral septum projections to the ventral CA1 influence sociability?
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作者 Dan Wang Di Zhao +12 位作者 Wentao Wang Fengai Hu Minghu Cui Jing Liu Fantao Meng Cuilan Liu Changyun Qiu Dunjiang Liu Zhicheng Xu Yameng Wang Yu Zhang Wei Li Chen Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1789-1801,共13页
Social dysfunction is a risk factor for several neuropsychiatric illnesses.Previous studies have shown that the lateral septum(LS)-related pathway plays a critical role in mediating social behaviors.Howeve r,the role ... Social dysfunction is a risk factor for several neuropsychiatric illnesses.Previous studies have shown that the lateral septum(LS)-related pathway plays a critical role in mediating social behaviors.Howeve r,the role of the connections between the LS and its downstream brain regions in social behavio rs remains unclea r.In this study,we conducted a three-chamber test using electrophysiological and chemogenetic approaches in mice to determine how LS projections to ventral CA1(vCA1)influence sociability.Our res ults showed that gamma-aminobutyric acid(GABA)-e rgic neuro ns were activated following social experience,and that social behavio rs were enhanced by chemogenetic modulation of these neurons.Moreover,LS GABAergic neurons extended their functional neural connections via vCA1 glutamatergic pyramidal neurons,and regulating LSGABA→vCA1Gluneural projections affected social behaviors,which were impeded by suppressing LSprojecting vCA1 neuronal activity or inhibiting GABAAreceptors in vCA1.These findings support the hypothesis that LS inputs to the vCA1 can control social prefe rences and social novelty behaviors.These findings provide new insights rega rding the neural circuits that regulate sociability. 展开更多
关键词 chemogenetics GABA receptor GABAergic neurons glutamatergic neurons lateral septum neural excitability neural projection social novelty social preference ventral CA1
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Asian Summer Monsoon Onset in Simulations and CMIP5 Projections Using Four Chinese Climate Models 被引量:9
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作者 ZOU Liwei ZHOU Tianjun 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第6期794-806,共13页
The reproducibility and future changes of the onset of the Asian summer monsoon were analyzed based on the simulations and projections under the Representative Concentration Pathways (RCP) scenario in which anthropo... The reproducibility and future changes of the onset of the Asian summer monsoon were analyzed based on the simulations and projections under the Representative Concentration Pathways (RCP) scenario in which anthropogenic emissions continue to rise throughout the 21 st century (i.e. RCP8.5) by all realizations from four Chinese models that participated in the Coupled Model Intercomparison Project Phase 5 (CMIP5). Delayed onset of the monsoon over the Arabian Sea was evident in all simulations for present-day climate, which was associated with a too weak simulation of the low-level Somali jet in May. A consistent advanced onset of the monsoon was found only over the Arabian Sea in the projections, where the advanced onset of the monsoon was accompanied by an increase of rainfall and an anomalous anticyclone over the northern Indian Ocean. In all the models except FGOALS-g2, the enhanced low-level Somali jet transported more water vapor to the Arabian Sea, whereas in FGOALS-g2 the enhanced rainfall was determined more by the increased wind convergence. Furthermore, and again in all models except FGOALS-g2, the equatorial SST warming, with maximum increase over the eastern Pacific, enhanced convection in the central West Pacific and reduced convection over the eastern Indian Ocean and Maritime Continent region, which drove the anomalous anticyclonic circulation over the western Indian Ocean. In contrast, in FGOALS-g2, there was minimal (near-zero) warming of projected SST in the central equatorial Pacific, with decreased convection in the central West Pacific and enhanced convection over the Maritime Continent. The broader-scale differences among the models across the Pacific were related to both the differences in the projected SST pattern and in the present-day simulations. 展开更多
关键词 Asian summer monsoon ONSET climate projection Chinese climate models
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Asymmetry of Surface Climate Change under RCP2.6 Projections from the CMIP5 Models 被引量:3
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作者 辛晓歌 程彦杰 +2 位作者 汪方 吴统文 张洁 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第3期796-805,共10页
The multi-model ensemble (MME) of 20 models from the Coupled Model Intercomparison Project Phase Five (CMIP5) was used to analyze surface climate change in the 21st century under the representative con- centration... The multi-model ensemble (MME) of 20 models from the Coupled Model Intercomparison Project Phase Five (CMIP5) was used to analyze surface climate change in the 21st century under the representative con- centration pathway RCP2.6, to reflect emission mitigation efforts. The maximum increase of surface air temperature (SAT) is 1.86℃ relative to the pre-industrial level, achieving the target to limit the global warming to 2℃. Associated with the "increase-peak-decline" greenhouse gases (GHGs) concentration path- way of RCP2.6, the global mean SAT of MME shows opposite trends during two time periods: warming during 2006-55 and cooling during 2056-2100. Our results indicate that spatial distribution of the linear trend of SAT during the warming period exhibited asymmetrical features compared to that during the cool- ing period. The warming during 2006-55 is distributed globally, while the cooling during 2056-2100 mainly occurred in the NH, the South Indian Ocean, and the tropical South Atlantic Ocean. Different dominant roles of heat flux in the two time periods partly explain the asymmetry. During the warming period, the latent heat flux and shortwave radiation both play major roles in heating the surface air. During the cooling period, the increase of net longwave radiation partly explains the cooling in the tropics and subtropics, which is associated with the decrease of total cloud amount. The decrease of the shortwave radiation accounts for the prominent cooling in the high latitudes of the NH. The surface sensible heat flux, latent heat flux, and shortwave radiation collectively contribute to the especial warming phenomenon in the high-latitude of the SH during the cooling period. 展开更多
关键词 climate models climate change projectION CMIP5 RCP2.6
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HF radar sea clutter rejection by nonlinear projections 被引量:3
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作者 Zhou Gongjian Jin Yonggao +1 位作者 Dong Huachun Quan Taifan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第4期733-737,共5页
In the background of signal detection for high frequency (I/F) radar, the sea clutter is quite significant and can mask some weak target signals. A new clutter rejection method named “nonlinear projection” is give... In the background of signal detection for high frequency (I/F) radar, the sea clutter is quite significant and can mask some weak target signals. A new clutter rejection method named “nonlinear projection” is given to improve the SNR of the target. This approach is based on the recent observation that HF sea clutter may be modeled as a nonlinear deterministic dynamical system. After approximating the multidimensional reconstruction of the clutter by a low-dimensional attractor, projections onto this attractor can separate the clutter from other components. Real sea clutter, simulated target data and real target data are used to show that a nonlinear clutter rejection method is a promising technique to suppress sea clutter and enhances target detection. 展开更多
关键词 HF radar target detection clutter rejection nonlinear projection.
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Projections of Wind Changes for 21st Century in China by Three Regional Climate Models 被引量:13
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作者 JIANG Ying Luo Yong +3 位作者 ZHAO Zongci SHI Ying XU Yinlong ZHU Jinhong 《Chinese Geographical Science》 SCIE CSCD 2010年第3期226-235,共10页
This paper examines the capability of three regional climate models (RCMs), i.e., RegCM3 (the International Centre for Theoretical Physics Regional Climate Model), PRECIS (Providing Regional Climates for Impacts Studi... This paper examines the capability of three regional climate models (RCMs), i.e., RegCM3 (the International Centre for Theoretical Physics Regional Climate Model), PRECIS (Providing Regional Climates for Impacts Studies) and CMM5 (the fifth-generation Pennsylvania State University-the National Center for Atmospheric Research of USA, NCAR Mesoscale Model) to simulate the near-surface-layer winds (10 m above surface) all over China in the late 20th century. Results suggest that like global climate models (GCMs), these RCMs have the certain capability of imitating the distribution of mean wind speed and fail to simulate the greatly weakening wind trends for the past 50 years in the country. However, RCMs especially RegCM3 have the better capability than that of GCMs to simulate the distribution and change feature of mean wind speed. In view of their merits, these RCMs were used to project the variability of near-surface-layer winds over China for the 21st century. The results show that 1) summer mean wind speed for 2020-2029 will be lower compared to those in 1990-1999 in most area of China; 2) annual and winter mean wind speed for 2081-2100 will be lower than those of 1971-1990 in the whole China; and 3) the changes of summer mean wind speed for 2081-2100 are uncertain. As a result, although climate models are absolutely necessary for projecting climate change to come, there are great uncertainties in projections, especially for wind speed, and these issues need to be further explored. 展开更多
关键词 wind speed projectION regional climate model global climate model
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Thailand's economic growth and structural development projections in the context of environmental control 被引量:1
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作者 Sompote Kunnoot 《Chinese Journal of Population,Resources and Environment》 2015年第3期272-280,共9页
Projections for 20 years of economic growth and change in the structure of the Thai economy were made for 180 sectors using a computable general equilibrium(CGE) model to compare the following four scenarios:(1) stand... Projections for 20 years of economic growth and change in the structure of the Thai economy were made for 180 sectors using a computable general equilibrium(CGE) model to compare the following four scenarios:(1) standard growth with infinite supply of factors,(2) finite land supply,(3) fixed use of agricultural chemicals,and(4) combined finite land supply with fixed use of agricultural chemicals.The computable projections suggest that the economic cost of hypothetical environmental control in agriculture is small and further weakened by urbanization.The computed structural development points to efficiency improvements specific to sectors to return the economy to balanced growth. 展开更多
关键词 STRUCTURAL development ENVIRONMENTAL control ECONOMIC growth projectION
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Discontinuous element pressure gradient stabilizations for compressible Navier-Stokes equations based on local projections 被引量:2
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作者 骆艳 冯民富 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第2期171-183,共13页
A pressure gradient discontinuous finite element formulation for the compressible Navier-Stokes equations is derived based on local projections. The resulting finite element formulation is stable and uniquely solvable... A pressure gradient discontinuous finite element formulation for the compressible Navier-Stokes equations is derived based on local projections. The resulting finite element formulation is stable and uniquely solvable without requiring a B-B stability condition. An error estimate is Obtained. 展开更多
关键词 discontinuous finite element methods pressure gradient projection methods compressible Navier-Stokes equations error estimation
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BERGMAN TYPE PROJECTIONS ON L^p SPACES 被引量:1
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作者 Kehe Zhu 《Analysis in Theory and Applications》 2005年第2期157-165,共9页
The paper is a survey on the action of Bergman type projections on various Lp on three types of holomorphic function spaces: weighted Bergman spaces, the Bloch spaces. The focus is space, and diagonal Besov spaces.
关键词 Bergman projection Bergman kernel integral operator
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Climate Change Projections and the Associated Potential Impacts for Somalia 被引量:1
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作者 Linda Ajuang Ogallo Philip Omondi +1 位作者 Gilbert Ouma Gordon Wayumba 《American Journal of Climate Change》 2018年第2期153-170,共18页
Somalia has faced severe challenges linked to climate variability, which has been exacerbated by conflict and limited governance that persisted for decades. Today climate extremes such as floods, drought, and coastal ... Somalia has faced severe challenges linked to climate variability, which has been exacerbated by conflict and limited governance that persisted for decades. Today climate extremes such as floods, drought, and coastal marine severe systems among others are always associated with the destruction of property and livelihoods;losses of lives lost, migrations, and resource based conflicts among many other miseries. Intergovernmental Panel on Climate Change (IPCC) has shown that climate change is real and requires sound knowledge of local future climate change scenarios. The study attempted to provide projected rainfall and temperature change scenarios over Lower Jubba, Somalia. This was done using the downscaled Coordinated Regional Downscaling Experiment (CORDEX) RCMs data. The simulated temperature and rainfall data derived from the CORDEX RCMs ensemble were compared with the observed data. The study focused on the IPCC projected periods of 2030, 2050 and 2070 benchmarks. Analysis of the projected rainfall indicated a decreasing trend in rainfall leading up to 2030 followed by an increase in rainfall with the 2050 and 2070 scenarios. In the case of temperature, the projections from all the models showed increase in minimum and maximum temperatures in all seasons and sub periods, like being observed by temperature projection over other parts of the world. The 2030, 2050 and 2070 projected rainfall and temperature change scenarios show that Somalia future development and livelihoods will in future face increased threats of climate extremes unless effective climate smart adaptation systems form integral components of national development strategies. 展开更多
关键词 CLIMATE CHANGE CLIMATE MODELING SOMALIA projections CORDEX
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Approximately Conformal,Equivalent and Equidistant Map Projections 被引量:1
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作者 Miljenko LAPAINE Nedjeljko FRANCULA 《Journal of Geodesy and Geoinformation Science》 2022年第3期33-40,共8页
If geodetic coordinates from an ellipsoid are included in the equations of a projection for mapping a sphere instead of geographical coordinates,the result will be a projection of the ellipsoid into a plane.This will ... If geodetic coordinates from an ellipsoid are included in the equations of a projection for mapping a sphere instead of geographical coordinates,the result will be a projection of the ellipsoid into a plane.This will slightly change the distortion distribution of the initial map projection.The question is to what extent the replacement of geographical with geodetic coordinates will affect this change.In this paper,we deal with conformal,equal-area and equidistant projections of the sphere,which we modify by using geodetic coordinates instead of geographical ones.The result will be an approximately conformal,approximately equal-area and approximately equidistant projection.It is shown that in this case the maximum distortion of the angles in approximately conformal projections will be approximately 23.09′,the maximum distortion of the area in approximately equal-area projections less than 0.7% and the maximum distortion of lengths in approximately equidistant projections less than 0.7%,therefore on the maps imperceptible. 展开更多
关键词 map projections double mapping approximately conformal projection approximately equal-area projection approximately equidistant projection
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Downscaled climate change projections for the Hindu Kush Himalayan region using CORDEX South Asia regional climate models 被引量:3
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作者 Jayanarayanan SANJAY Raghavan KRISHNAN +2 位作者 Arun Bhakta SHRESTHA Rupak RAJBHANDARI REN Guo-Yu 《Advances in Climate Change Research》 SCIE CSCD 2017年第3期185-198,共14页
This study assessed the regional climate models (RCMs) employed in the Coordinated Regional climate Downscaling Experiment (CORDEX) South Asia framework to investigate the qualitative aspects of future change in seaso... This study assessed the regional climate models (RCMs) employed in the Coordinated Regional climate Downscaling Experiment (CORDEX) South Asia framework to investigate the qualitative aspects of future change in seasonal mean near surface air temperature and precipitation over the Hindu Kush Himalayan (HKH) region. These RCMs downscaled a subset of atmosphere ocean coupled global climate models (AOGCMs) in the Coupled Model Intercomparison Project phase 5 (CMIP5) to higher 50 km spatial resolution over a large domain covering South Asia for two representation concentration pathways (RCP4.5 and RCP8.5) future scenarios. The analysis specifically examined and evaluated multi-model and multi-scenario climate change projections over the hilly sub-regions within HKH for the near-future (2036e2065) and far-future (2066e2095) periods. The downscaled multi-RCMs provide relatively better confidence than their driving AOGCMs in projecting the magnitude of seasonal warming for the hilly sub-region within the Karakoram and northwestern Himalaya, with higher projected change of 5.4 C during winter than of 4.9 C during summer monsoon season by the end of 21st century under the high-end emissions (RCP8.5) scenario. There is less agreement among these RCMs on the magnitude of the projected warming over the other sub-regions within HKH for both seasons, particularly associated with higher RCM uncertainty for the hilly sub-region within the central Himalaya. The downscaled multi-RCMs show good consensus and low RCM uncertainty in projecting that the summer monsoon precipitation will intensify by about 22% in the hilly subregion within the southeastern Himalaya and Tibetan Plateau for the far-future period under the RCP8.5 scenario. There is low confidence in the projected changes in the summer monsoon and winter season precipitation over the central Himalaya and in the Karakoram and northwestern Himalaya due to poor consensus and moderate to high RCM uncertainty among the downscaled multi-RCMs. Finally, the RCM related uncertainty is found to be large for the projected changes in seasonal temperature and precipitation over the hilly sub-regions within HKH by the end of this century, suggesting that improving the regional processes and feedbacks in RCMs are essential for narrowing the uncertainty, and for providing more reliable regional climate change projections suitable for impact assessments in HKH region. 展开更多
关键词 CMIP5 CORDEX SOUTH ASIA REGIONAL CLIMATE models HINDU Kush HIMALAYAN CLIMATE change projections
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The continuous wavelet projections algorithm: A practical spectral-feature-mining approach for crop detection 被引量:2
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作者 Xiaohu Zhao Jingcheng Zhang +3 位作者 Ruiliang Pu Zaifa Shu Weizhong He Kaihua Wu 《The Crop Journal》 SCIE CSCD 2022年第5期1264-1273,共10页
Spectroscopy can be used for detecting crop characteristics. A goal of crop spectrum analysis is to extract effective features from spectral data for establishing a detection model. An ideal spectral feature set shoul... Spectroscopy can be used for detecting crop characteristics. A goal of crop spectrum analysis is to extract effective features from spectral data for establishing a detection model. An ideal spectral feature set should have high sensitivity to target parameters but low information redundancy among features.However, feature-selection methods that satisfy both requirements are lacking. To address this issue,in this study, a novel method, the continuous wavelet projections algorithm(CWPA), was developed,which has advantages of both continuous wavelet analysis(CWA) and the successive projections algorithm(SPA) for generating optimal spectral feature set for crop detection. Three datasets collected for crop stress detection and retrieval of biochemical properties were used to validate the CWPA under both classification and regression scenarios. The CWPA generated a feature set with fewer features yet achieving accuracy comparable to or even higher than those of CWA and SPA. With only two to three features identified by CWPA, an overall accuracy of 98% in classifying tea plant stresses was achieved, and high coefficients of determination were obtained in retrieving corn leaf chlorophyll content(R^(2)= 0.8521)and equivalent water thickness(R^(2)= 0.9508). The mechanism of the CWPA ensures that the novel algorithm discovers the most sensitive features while retaining complementarity among features. Its ability to reduce the data dimension suggests its potential for crop monitoring and phenotyping with hyperspectral data. 展开更多
关键词 HYPERSPECTRAL Crop parameters Crop phenotyping Continuous wavelet analysis Successive projections algorithm
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Model Projections of East Asian Summer Climate under the ‘Free Arctic’ Scenario 被引量:11
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作者 Wang Hui-Jun Zhang Ying 《Atmospheric and Oceanic Science Letters》 2010年第3期176-180,共5页
This paper addresses the ‘ice-free Arctic’ issue under the future global warming scenario. Four coupled climate models used in the third phase of the Coupled Model Intercomparison Project (CMIP3) were selected to pr... This paper addresses the ‘ice-free Arctic’ issue under the future global warming scenario. Four coupled climate models used in the third phase of the Coupled Model Intercomparison Project (CMIP3) were selected to project summer climate conditions over East Asia once the Arctic becomes ice-free. The models project that an ice-free Arctic summer will begin in the 2060s under the SRESA1B (according to IPCC Special Reports on Emissions Scenarios) simulations. Our results show that the East Asian summer monsoons will tend to be stronger and that the water vapor transport to central northern China will be strengthened, leading to increased summer precipitation in central northern China. The models also project an intensified Antarctic Oscillation, a condition which favors increased precipitation in South China’s Yangtze River Valley. The overall precipitation in Northwest China is projected to increase under ice-free Arctic summer conditions. 展开更多
关键词 ice-free Arctic East Asian monsoon global warming projections
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Supervised local and non-local structure preserving projections with application to just-in-time learning for adaptive soft sensor 被引量:4
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作者 邵伟明 田学民 王平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期1925-1934,共10页
In soft sensor field, just-in-time learning(JITL) is an effective approach to model nonlinear and time varying processes. However, most similarity criterions in JITL are computed in the input space only while ignoring... In soft sensor field, just-in-time learning(JITL) is an effective approach to model nonlinear and time varying processes. However, most similarity criterions in JITL are computed in the input space only while ignoring important output information, which may lead to inaccurate construction of relevant sample set. To solve this problem, we propose a novel supervised feature extraction method suitable for the regression problem called supervised local and non-local structure preserving projections(SLNSPP), in which both input and output information can be easily and effectively incorporated through a newly defined similarity index. The SLNSPP can not only retain the virtue of locality preserving projections but also prevent faraway points from nearing after projection,which endues SLNSPP with powerful discriminating ability. Such two good properties of SLNSPP are desirable for JITL as they are expected to enhance the accuracy of similar sample selection. Consequently, we present a SLNSPP-JITL framework for developing adaptive soft sensor, including a sparse learning strategy to limit the scale and update the frequency of database. Finally, two case studies are conducted with benchmark datasets to evaluate the performance of the proposed schemes. The results demonstrate the effectiveness of LNSPP and SLNSPP. 展开更多
关键词 Adaptive soft sensor Just-in-time learning Supervised local and non-local structure preserving projections Locality preserving projections Database monitoring
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Robustness of Precipitation Projections in China:Comparison between CMIP5 and CMIP3 Models 被引量:1
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作者 CHEN Huo-Po SUN Jian-Qi 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第1期67-73,共7页
Three sources of uncertainty in model projections of precipitation change in China for the 21st century were separated and quantified: internal variability,inter-model variability,and scenario uncertainty.Simulations ... Three sources of uncertainty in model projections of precipitation change in China for the 21st century were separated and quantified: internal variability,inter-model variability,and scenario uncertainty.Simulations from models involved in the third phase and the fifth phase of the Coupled Model Intercomparison Project(CMIP3 and CMIP5) were compared to identify improvements in the robustness of projections from the latest generation of models.No significant differences were found between CMIP3 and CMIP5 in terms of future precipitation projections over China,with the two datasets both showing future increases.The uncertainty can be attributed firstly to internal variability,and then to both inter-model and internal variability.Quantification analysis revealed that the uncertainty in CMIP5 models has increased by about 10%–60% with respect to CMIP3,despite significant improvements in the latest generation of models.The increase is mainly due to the increase of internal variability in the initial decades,and then mainly due to the increase of inter-model variability thereafter,especially by the end of this century.The change in scenario uncertainty shows no major role,but makes a negative contribution to begin with,and then an increase later. 展开更多
关键词 PRECIPITATION projectION UNCERTAINTY CMIP3 CMIP5
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Extreme climate projections over the transboundary Koshi River Basin using a high resolution regional climate model 被引量:1
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作者 Rupak RAJBHANDARI Arun Bhakta SHRESTHA +2 位作者 Santosh NEPAL Shahriar WAHID REN Guo-Yu 《Advances in Climate Change Research》 SCIE CSCD 2017年第3期199-211,共13页
The high-resolution climate model Providing REgional Climates for Impacts Studies (PRECIS) was used to project the changes in futureextreme precipitation and temperature over the Koshi River Basin for use in impact as... The high-resolution climate model Providing REgional Climates for Impacts Studies (PRECIS) was used to project the changes in futureextreme precipitation and temperature over the Koshi River Basin for use in impact assessments. Three outputs of the Quantifying Uncertaintiesin Model Prediction (QUMP) simulations using the Hadley Centre Couple Model (HadCM3) based on the IPCC SRES A1B emission scenario were used to project the future climate. The projections were analysed for three time slices, 2011e2040 (near future), 2041e2070 (mid-century), and 2071e2098 (distant future). The results show an increase in the future frequency and intensity of climate extremes events such as dry days, consecutive dry days, and very wet days (95th percentile), with greater increases over the southern plains than in the mountainous area to the north. A significant decrease in moderate rainfall days (75th percentile) is projected over the middle (high) mountain and trans-Himalaya areas. Increases are projected in both the extreme maximum and extreme minimum temperature, with a slightly higher rate in minimum temperature. The number of warm days is projected to increase throughout the basin, with more rapid rates in the trans-Himalayan and middle mountain areas than in the plains. Warm nights are also projected to increase, especially in the southern plains. A decrease is projected in cold days and cold nights indicating overall warming throughout the basin. 展开更多
关键词 CLIMATE change CLIMATE projectION Koshi basin PRECIS EXTREME CLIMATE
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Projections of changes in marine environment in coastal China seas over the 21^st century based on CMIP5 models 被引量:6
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作者 TAN Hongjian CAI Rongshuo +1 位作者 HUO Yunlong GUO Haixia 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第6期1676-1691,共16页
The increases of atmospheric carbon dioxide and other greenhouse gases have caused fundamental changes to the physical and biogeochemical properties of the oceans,and it will continue to occur in the foreseeable futur... The increases of atmospheric carbon dioxide and other greenhouse gases have caused fundamental changes to the physical and biogeochemical properties of the oceans,and it will continue to occur in the foreseeable future.Based on the outputs of nine Earth System Models from the fifth phase of the Coupled Model Intercomparison Project(CMIP5),in this study,we provided a synoptic assessment of future changes in the sea surface temperature(SST),salinity,dissolved oxygen(DO),seawater pH,and marine net primary productivity(NPP)in the coastal China seas over the 21st century.The results show that the mid-high latitude areas of the coastal China seas(East China Seas(ECS),including the Bohai Sea,Yellow Sea,and East China Sea)will be simultaneously exposed to enhanced warming,deoxygenation,acidification,and decreasing NPP as a consequence of increasing greenhouse gas emissions.The magnitudes of the changes will increase as the greenhouse gas concentrations increase.Under the high emission scenario(Representative Concentration Pathway 8.5),the ECS will experience an SST increase of 3.24±1.23℃,a DO concentration decrease of 10.90±3.92μmol/L(decrease of 6.3%),a pH decline of 0.36±0.02,and a NPP reduction of-17.7±6.2 mg/(m2·d)(decrease of 12.9%)relative to the current levels(1980-2005)by the end of this century.The co-occurrence of these changes and their cascade effects are expected to induce considerable biological and ecological responses,thereby making the ECS among the most vulnerable ocean areas to future climate change.Despite high uncertainties,our results have important implications for regional marine assessments. 展开更多
关键词 Coupled Model Intercomparison project(CMIP5) sea surface temperature(SST) dissolved oxygen(DO) seawater pH net primary productivity
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Multidecadal Trends in Large-Scale Annual Mean SATa Based on CMIP5 Historical Simulations and Future Projections 被引量:4
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作者 Nan Xing Jianping Li Lanning Wang 《Engineering》 SCIE EI 2017年第1期136-143,共8页
Based on observations and Coupled Model lntercomparison Project Phase 5 (CMIP5) results, multidecadal variations and trends in annual mean surface air temperature anomalies (SATa) at global, hemispheric, and hemis... Based on observations and Coupled Model lntercomparison Project Phase 5 (CMIP5) results, multidecadal variations and trends in annual mean surface air temperature anomalies (SATa) at global, hemispheric, and hemispheric land and ocean scales in the past and under the future scenarios of two representative concentration pathways (RCPs) are analyzed. Fifteen models are selected based on their performances in capturing the temporal variability, long-term trend, multidecadal variations, and trends in global annual mean SATa. Observational data analysis shows that the multidecadal variations in annual mean SATa of the land and ocean in the northern hemisphere (NH) and of the ocean in the southern hemisphere (SH) are similar to those of the global mean, showing an increase during the 1900-1944 and 1971-2000 periods, and flattening or even cooling during the 1945-1970 and 2001-2013 periods. These observed characteristics are basically reproduced by the models. However, SATa over SH land show an increase during the 1945-1970 period, which differs from the other hemispheric scales, and this feature is not captured well by the models. For the recent hiatus period (2001-2013), the projected trends of BCC-CSM1-1-m, CMCC-CM, GFDL-ESM2M, and NorESM1-ME at the global and hemispheric scales are closest to the observations based on RCP4.5 and RCP8.5 scenarios, suggesting that these four models have better projection capability in SATa. Because these four models are better at simulating and projecting the multidecadal trends of SATa, they are selected to analyze future SATa variations at the global and hemispheric scales during the 2006-2099 period. The selected multi-model ensemble (MME) projected trends in annual mean SATa for the globe, NH, and SH under RCP4.5 (RCP8.5) are 0.17 (0.29) ℃, 0.22 (0.36) ℃, and 0.11 (0.23) ℃-decade-1 in the 21st century, respectively. These values are significantly lower than the projections of CMIP5 MME without model selection. 展开更多
关键词 Surface air temperature anomalies (SATa) Multidecadal trend Coupled Model lntercomparison project Phase 5 (CMIPS) projection
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Global and Regional Trends and Projections of Infective Endocarditis-Associated Disease Burden and Attributable Risk Factors from 1990 to 2030 被引量:1
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作者 Lijin Lin Yemao Liu +10 位作者 Juanjuan Qin Fang Lei Wenxin Wang Xuewei Huang Weifang Liu Xingyuan Zhang Zhigang She Peng Zhang Xiaojing Zhang Zhaoxia Jin Hongliang Li 《Chinese Medical Sciences Journal》 CAS CSCD 2022年第3期181-194,I0003,共15页
Objective To forecast the future burden and its attributable risk factors of infective endocarditis(IE).Methods We analyzed the disease burden of IE and its risk factors from 1990 to 2019 using the Global Burden of Di... Objective To forecast the future burden and its attributable risk factors of infective endocarditis(IE).Methods We analyzed the disease burden of IE and its risk factors from 1990 to 2019 using the Global Burden of Disease 2019 database and projected the disease burden from 2020 to 2030 using a Bayesian age-period-cohort model.Results By 2030,the incidence of IE will increase uncontrollably on a global scale,with developed countries having the largest number of cases and developing countries experiencing the fastest growth.The affected population will be predominantly males,but the gender gap will narrow.The elderly in high-income countries will bear the greatest burden,with a gradual shift to middle-income countries.The incidence of IE in countries with middle/high-middle social-demographic indicators(SDI) will surpass that of high SDI countries.In China,the incidence rate and the number of IE will reach 18.07 per 100,000 and 451,596 in 2030,respectively.IEassociated deaths and heart failure will continue to impose a significant burden on society,the burden on women will increase and surpass that on men,and the elderly in high-SDI countries will bear the heaviest burden.High systolic blood pressure has become the primary risk factor for IE-related death.Conclusions This study provides comprehensive analyses of the disease burden and risk factors of IE worldwide over the next decade.The IE-associated incidence will increase in the future and the death and heart failure burden will not be appropriately controlled.Gender,age,regional,and country heterogeneity should be taken seriously to facilitate in making effective strategies for lowering the IE disease burden. 展开更多
关键词 infective endocarditis disease burden risk factors Bayesian age-period-cohort model projectION
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