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Cancer mortality trends in China from 2013-2021 and projections to 2030
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作者 Xin Liang Yifei Yao +2 位作者 Xiang Li Ting Gao Xiaoqiu Dai 《Cancer Biology & Medicine》 2025年第10期1223-1239,I0023-I0036,共31页
Objective:This study aimed to analyze the temporal trends in cancer mortality in China from 2013-2021 and project the future trends through 2030.Methods:This study was based on the China Causes of Death Surveillance D... Objective:This study aimed to analyze the temporal trends in cancer mortality in China from 2013-2021 and project the future trends through 2030.Methods:This study was based on the China Causes of Death Surveillance Dataset,which covers 2.37 billion person-years.Age-standardized mortality rates(ASMRs)were calculated using Segi’s world standard population and the trends were evaluated via Joinpoint regression.Bayesian age-period-cohort models were used for mortality projections.Contributions of demographic changes(population size and age structure)and risk factors to the mortality burden were quantified using the decomposition analysis.Results:The combined ASMRs for all cancers decreased annually by 2.3%,driven by significant declines in esophageal(4.8%),stomach(4.5%),and liver cancers(2.7%).In contrast,the pancreatic and prostate cancer ASMRs increased by 2.0% and 3.4% annually,respectively.Urban areas demonstrated a more rapid decline in the combined ASMRs for all cancers[average annual percent change(AAPC)=-3.0% in urban areas vs.-2.0% in rural areas],highlighting persistent disparities.Population aging contributed 20%-50% to death increases between 2013 and 2021.The combined ASMRs for all cancers,like the findings of temporal trend analyses,will continue to decrease and the regional(urban and rural)difference is projected to simulate that of the temporal trend through 2030.In fact,cancer deaths are projected to reach 2.4 million by 2030.Conclusions:The cancer burden in China is facing the dual challenges of population aging and urban-rural disparities.It is necessary to prioritize rural screening,control risk factors,such as smoking and diet,and integrate more efficacious cancer prevention and control programmes into the policy to reduce mortality in the future. 展开更多
关键词 Cancer mortality TRENDS projections 2030 China
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Global burden of cervical cancer:current estimates,temporal trend and future projections based on the GLOBOCAN 2022 被引量:3
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作者 Jie Wu Qianyun Jin +10 位作者 Yunmeng Zhang Yuting Ji Jingjing Li Xiaomin Liu Hongyuan Duan Zhuowei Feng Ya Liu Yacong Zhang Zhangyan Lyu Lei Yang Yubei Huang 《Journal of the National Cancer Center》 2025年第3期322-329,共8页
Background Cervical cancer is the only cancer that can be eliminated worldwide.Tracking the latest burden of cervical cancer is critical toward the targets set by World Health Organization(WHO)to eliminate cervical ca... Background Cervical cancer is the only cancer that can be eliminated worldwide.Tracking the latest burden of cervical cancer is critical toward the targets set by World Health Organization(WHO)to eliminate cervical cancer as a major public health problem.Methods All data were extracted from the Global Cancer Observatory(GLOBOCAN)2022.Age-standardized incidence rate(ASIR)and mortality rates(ASMR)of cervical cancer were compared and linked to Human Development Index(HDI)between populations.The estimated annual percentage changes(EAPCs)were used to characterize the temporal trend in ASIR/ASMR,and demographic estimates were projected up to 2050.Results Globally,an estimated 662,044 cases(ASIR:14.12/100,000)and 348,709 deaths(ASMR:7.08/100,000)from cervical cancer occurred in 2022,corresponding to the fourth cause of cancer morbidity and mortality in women worldwide.Specifically,42%of cases and 39%of deaths occurred in China(23%and 16%)and India(19%and 23%).Both ASIR and ASMR of cervical cancer decreased with HDI,and similar decreasing links were observed for both early-onset(0–39 years)and late-onset(≥40 years)cervical cancer.Both ASIR and ASMR of overall cervical cancer showed decreasing trends during 2003–2012(EAPC:0.04%and-1.03%);however,upward trends were observed for early-onset cervical cancer(EAPC:1.16%and 0.57%).If national rates in 2022 remain stable,the estimated cases and deaths from cervical cancer are projected to increase by 56.8%and 80.7%up to 2050.Moreover,the projected increase of early-onset cervical cancer is mainly observed in transitioning countries,while decreased burden is expected in transitioned countries.Conclusions Cervical cancer remains a common cause of cancer death in many countries,especially in transitioning countries.Unless scaling-up preventive interventions,human papillomavirus(HPV)vaccination and cervical cancer screening,as well as systematic cooperation within government,civil societies,and private enterprises,the global burden of cervical cancer would be expected to increase in the future. 展开更多
关键词 Cervical cancer INCIDENCE MORTALITY Temporal trend Future projection
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Predictable and Unpredictable Modes of Northern Hemisphere Atmospheric Circulation in CMIP6:Evaluation and Projections
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作者 Kairan YING Dabang JIANG Linhao ZHONG 《Advances in Atmospheric Sciences》 2026年第1期135-156,共22页
Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both g... Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both global and regional climates.This study assesses the performance of models participating in phase 6 of the Coupled Model Intercomparison Project in simulating interannual variability modes of Northern Hemisphere 500-hPa geopotential height during winter and summer,distinguishing predictable(potentially predictable on seasonal or longer timescales)and unpredictable(intraseasonal and essentially unpredictable at long range)components,using reanalysis data and a variance decomposition method.Although most models effectively capture unpredictable modes in reanalysis,their ability to reproduce dominant predictable modes-specifically the Pacific-North American pattern,Arctic Oscillation,and Western Pacific Oscillation in winter,and the East Atlantic and North Atlantic Oscillations in summer-varies notably.An optimal ensemble is identified to distinguish(a)predictable-external modes,dominated by external forcing,and(b)predictable-internal modes,associated with slow internal variability,during the historical period(1950-2014)and the SSP5-8.5 scenario(2036-2100).Under increased radiative forcing,the leading winter/summer predictable-external mode exhibits a more uniform spatial distribution,remarkably larger trend and annual variance,and enhanced height-sea surface temperature(SST)covariance under SSP5-8.5 compared to historical conditions.The dominant winter/summer predictable-internal modes also exhibit increased variance and height-SST covariance under SSP5-8.5,along with localized changes in spatial configuration.Minimal changes are observed in spatial distribution or variance for dominant winter/summer unpredictable modes under SSP5-8.5.This study,from a predictive perspective,deepens our understanding of model uncertainties and projected changes in circulations. 展开更多
关键词 interannual mode of atmospheric circulation CMIP6 predictable unpredictable EVALUATION PROJECTION
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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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Face recognition using illuminant locality preserving projections
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作者 刘朋樟 沈庭芝 林健文 《Journal of Beijing Institute of Technology》 EI CAS 2011年第1期111-116,共6页
A novel supervised manifold learning method was proposed to realize high accuracy face recognition under varying illuminant conditions. The proposed method, named illuminant locality preserving projections (ILPP), e... A novel supervised manifold learning method was proposed to realize high accuracy face recognition under varying illuminant conditions. The proposed method, named illuminant locality preserving projections (ILPP), exploited illuminant directions to alleviate the effect of illumination variations on face recognition. The face images were first projected into low dimensional subspace, Then the ILPP translated the face images along specific direction to reduce lighting variations in the face. The ILPP reduced the distance between face images of the same class, while increase the dis tance between face images of different classes. This proposed method was derived from the locality preserving projections (LPP) methods, and was designed to handle face images with various illumi nations. It preserved the face image' s local structure in low dimensional subspace. The ILPP meth od was compared with LPP and discriminant locality preserving projections (DLPP), based on the YaleB face database. Experimental results showed the effectiveness of the proposed algorithm on the face recognition with various illuminations. 展开更多
关键词 locality preserving projections LPP illuminant direction illuminant locality preser ving projections (ILPP) face recognition
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The Cartography of Focus and Interrogative Projections inǸjò`-Kóo
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作者 Simeon Olaogun 《宏观语言学》 2022年第1期77-100,共24页
Researches on cartography have made universal predictions on the hierarchies of functional projections in language.Based on this assumption,the structural maps established by Rizzi(1997,2001b)for the left-peripheral e... Researches on cartography have made universal predictions on the hierarchies of functional projections in language.Based on this assumption,the structural maps established by Rizzi(1997,2001b)for the left-peripheral elements suggest very strongly that Interrogative dominates Focus.Nevertheless,a straight-jacket adoption of this proposed hierarchical order to account for these left-peripheral projections inǸjò`-Kóo would be counterintuitive.Therefore,leaning on empirical and theoretical evidence,the paper calls to question the universality of the cartographers’claim,and argues that the opposite of the view is true ofǸjò`-Kóo.The paper adopts fieldwork method for data elicitation and descriptive approach as well as minimalist program for analysis of data.Data used in this study were elicited from purposively selected native speakers based on language proficiency.Data were acquired with syntactic checklist and structured interviews,and were subjected to interlinear and qualitative analysis. 展开更多
关键词 CARTOGRAPHY functional projections left-peripheral elements focus and interrogative projections Ǹjò`-Kóo
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Onto Orthogonal Projections in the Space of Polynomials Pn[x]
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作者 Jean-Francois Niglio 《Journal of Applied Mathematics and Physics》 2023年第1期22-45,共24页
In this article, I consider projection groups on function spaces, more specifically the space of polynomials P<sub>n</sub>[x]. I will show that a very similar construct of projection operators allows us to... In this article, I consider projection groups on function spaces, more specifically the space of polynomials P<sub>n</sub>[x]. I will show that a very similar construct of projection operators allows us to project into the subspaces of P<sub>n</sub>[x] where the function h &#8712;P<sub>n</sub>[x] represents the closets function to f &#8712;P<sub>n</sub>[x] in the least square sense. I also demonstrate that we can generalise projections by constructing operators i.e. in R<sup>n+1</sup> using the metric tensor on P<sub>n</sub>[x]. This allows one to project a polynomial function onto another by mapping it to its coefficient vector in R<sup>n+1</sup>. This can be also achieved with the Kronecker Product as detailed in this paper. 展开更多
关键词 Polynomials and projections projections The Kronecker Product Idempotent Operators
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Surface Detection of Continuous Casting Slabs Based on Curvelet Transform and Kernel Locality Preserving Projections 被引量:19
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作者 AI Yong-hao XU Ke 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2013年第5期80-86,共7页
Longitudinal cracks are common defects of continuous casting slabs and may lead to serious quality accidents. Image capturing and recognition of hot slabs is an effective way for on-line detection of cracks, and recog... Longitudinal cracks are common defects of continuous casting slabs and may lead to serious quality accidents. Image capturing and recognition of hot slabs is an effective way for on-line detection of cracks, and recognition of cracks is essential because the surface of hot slabs is very complicated. In order to detect the surface longitudinal cracks of the slabs, a new feature extraction method based on Curvelet transform and kernel locality preserving projections (KLPP) is proposed. First, sample images are decomposed into three levels by Curvelet transform. Second, Fourier transform is applied to all sub-band images and the Fourier amplitude spectrum of each sub-band is computed to get features with translational invariance. Third, five kinds of statistical features of the Fourier amplitude spectrum are computed and combined in different forms. Then, KLPP is employed for dimensionality reduction of the obtained 62 types of high-dimensional combined features. Finally, a support vector machine (SVM) is used for sample set classification. Experiments with samples from a real production line of continuous casting slabs show that the algorithm is effective to detect longitudinal cracks, and the classification rate is 91.89%. 展开更多
关键词 surface detection continuous casting slab Curvelet transform feature extraction kernel locality preserving projections
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The continuous wavelet projections algorithm: A practical spectral-feature-mining approach for crop detection 被引量:4
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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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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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Full-viewpoint 3D Space Object Recognition Based on Kernel Locality Preserving Projections 被引量:2
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作者 孟钢 姜志国 +2 位作者 刘正一 张浩鹏 赵丹培 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2010年第5期563-572,共10页
Space object recognition plays an important role in spatial exploitation and surveillance, followed by two main problems: lacking of data and drastic changes in viewpoints. In this article, firstly, we build a three-... Space object recognition plays an important role in spatial exploitation and surveillance, followed by two main problems: lacking of data and drastic changes in viewpoints. In this article, firstly, we build a three-dimensional (3D) satellites dataset named BUAA Satellite Image Dataset (BUAA-SID 1.0) to supply data for 3D space object research. Then, based on the dataset, we propose to recognize full-viewpoint 3D space objects based on kernel locality preserving projections (KLPP). To obtain more accurate and separable description of the objects, firstly, we build feature vectors employing moment invariants, Fourier descriptors, region covariance and histogram of oriented gradients. Then, we map the features into kernel space followed by dimensionality reduction using KLPP to obtain the submanifold of the features. At last, k-nearest neighbor (kNN) is used to accomplish the classification. Experimental results show that the proposed approach is more appropriate for space object recognition mainly considering changes of viewpoints. Encouraging recognition rate could be obtained based on images in BUAA-SID 1.0, and the highest recognition result could achieve 95.87%. 展开更多
关键词 SATELLITES object recognition THREE-DIMENSIONAL image dataset full-viewpoint kernel locality preserving projections
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Whole-Brain Direct Inputs to and Axonal Projections from Excitatory and Inhibitory Neurons in the Mouse Primary Auditory Area 被引量:2
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作者 Mengting Zhao Miao Ren +6 位作者 Tao Jiang Xueyan Jia Xiaojun Wang Anan Li Xiangning Li Qingming Luo Hui Gong 《Neuroscience Bulletin》 SCIE CAS CSCD 2022年第6期576-590,共15页
Neurons in the primary auditory area(AUDp)innervate multiple brain regions with long-range projections while receiving informative inputs for diverse functions.However,the brain-wide connections of these neurons have ... Neurons in the primary auditory area(AUDp)innervate multiple brain regions with long-range projections while receiving informative inputs for diverse functions.However,the brain-wide connections of these neurons have not been comprehensively investigated.Here,we simultaneously applied virus-based anterograde and retrograde tracing,labeled the connections of excitatory and inhibitory neurons in the mouse AUDp,and acquired whole-brain information using a dual-channel fuorescence micro-optical sectioning tomography system.Quantified results showed that the two types of neurons received inputs with similar patterns but sent heterogeneous projections to downstream regions.In the isocortex,functionally different areas consistently sent feedback-dominated projections to these neurons,with concomitant laterallydominated projections from the sensory and limbic cortices to inhibitory neurons.In subcortical regions,the dorsal and medial parts of the non-lemniscal auditory thalamus(AT)were reciprocally connected to the AUDp,while the ventral part contained the most fibers of passage from the excitatory neurons and barely sent projections back,indicating the regional heterogeneity of the AUDp-AT circuit.Our results reveal details of the whole-brain network and provide new insights for further physiological and functional studies of the AUDp. 展开更多
关键词 Primary auditory area EXCITATORY Inhibitory Direct inputs Axonal 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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Approximately Conformal,Equivalent and Equidistant Map Projections 被引量:2
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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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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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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 and 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 project... 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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The functional roles of feedback projections in the visual system
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作者 寿天德 《Neuroscience Bulletin》 SCIE CAS CSCD 2010年第5期401-410,共10页
Neurons in the nervous system make connections with ascending feedforward projections and descending feedback projections,as well as projections from neural structures at the identical hierarchical level.These neurons... Neurons in the nervous system make connections with ascending feedforward projections and descending feedback projections,as well as projections from neural structures at the identical hierarchical level.These neurons form extremely complicated neural networks and pathways.Compared with the role of the feedforward projection,much less is known concerning the functional roles of the feedback projection.Visual cortex is a good model for studying functional roles of cortical feedback projections which involve many high functions,such as attention,searching and cognition.The present review mainly focused on the functional roles of feedback projections in the visual system. 展开更多
关键词 feedback projection feedforward projection visual system visual attention oblique effect
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Co-localization of two-color rAAV2-retro confirms the dispersion characteristics of efferent projections of mitral cells in mouse accessory olfactory bulb
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作者 Ning Zheng Zhi-Zhong Wang +6 位作者 Song-Wei Wang Fang-Jia Yang Xu-Tao Zhu Chen Lu Anne Manyande Xiao-Ping Rao Fu-Qiang Xu 《Zoological Research》 SCIE CAS CSCD 2020年第2期148-156,共9页
The accessory olfactory bulb(AOB), located at the posterior dorsal aspect of the main olfactory bulb(MOB), is the first brain relay of the accessory olfactory system(AOS), which can parallelly detect and process volat... The accessory olfactory bulb(AOB), located at the posterior dorsal aspect of the main olfactory bulb(MOB), is the first brain relay of the accessory olfactory system(AOS), which can parallelly detect and process volatile and nonvolatile social chemosignals and mediate different sexual and social behaviors with the main olfactory system(MOS). However, due to its anatomical location and absence of specific markers, there is a lack of research on the internal and external neural circuits of the AOB. This issue was addressed by singlecolor labeling and fluorescent double labeling using retrograde rAAVs injected into the bed nucleus of the stria terminalis(BST), anterior cortical amygdalar area(ACo), medial amygdaloid nucleus(MeA), and posteromedial cortical amygdaloid area(PMCo) in mice. We demonstrated the effectiveness of this AOB projection neuron labeling method and showed that the mitral cells of the AOB exhibited efferent projection dispersion characteristics similar to those of the MOB. Moreover, there were significant differences in the number of neurons projected to different brain regions, which indicated that each mitral cell in the AOB could project to a different number of neurons in different cortices. These results provide a circuitry basis to help understand the mechanism by which pheromone information is encoded and decoded in the AOS. 展开更多
关键词 Accessory OLFACTORY bulb Efferent projections RETROGRADE rAAVs Projection neuron labeling Dispersion characteristics CIRCUITRY basis
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Effects of Sunspot on the Multi-Decadal Climate Projections
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作者 ZHAO Zong-Ci LUO Yong HUANG Jian-Bin 《Advances in Climate Change Research》 SCIE 2014年第1期51-56,共6页
Most model generated projections of climate change for the future decades only consider anthro- pogenic activities. It is hard to think about the effects of solar activity and volcano effects, because the pre- diction... Most model generated projections of climate change for the future decades only consider anthro- pogenic activities. It is hard to think about the effects of solar activity and volcano effects, because the pre- dictions of both solar activity and volcano effects are difficult. But as we know, the sun is the source of en- ergy for the Earth's climate system, and observations show it to be a variable star. 展开更多
关键词 RCP Effects of Sunspot on the Multi-Decadal Climate projections QBO cycle CESM Figure
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