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Assessment of the diurnal and semidiurnal signals induced by monument thermal effect with time series of very short GPS baselines
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作者 Kaihua Wang Linsong Yang +3 位作者 Shuangping Li Tengxu Zhang Zhao Li Liansheng Deng 《Geodesy and Geodynamics》 2025年第2期158-171,共14页
The monument thermal effect(MTE)displacements could result in periodical signals with several mil-limeters magnitudes in the vertical and horizontal GPS position time series.However,the interaction ofvarious origins o... The monument thermal effect(MTE)displacements could result in periodical signals with several mil-limeters magnitudes in the vertical and horizontal GPS position time series.However,the interaction ofvarious origins of periodic signals in GPS observations makes it difficult to isolate the millimeter-levelMTE displacement from other signals and noises.In this study,to assess the diurnal and semidiurnalsignals induced by MTE,we processed 12 very short GPS baselines(VSGB)with length<150 m.Themonument pairs for each baseline differ in their heights,horizontal structure,or base foundations.Meanwhile,two zero-baselines were also processed as the control group.Results showed that the sea-sonal signals observed in VSGB time series in the horizontal and vertical directions,were mainly inducedby seasonal MTE.Time-varying diurnal and semidiurnal signals with amplitude up to 4 mm wereobserved in the vertical direction for baselines with monument height difference(MHD)larger than10 m.Horizontal diurnal signal with an amplitude of about 2 mm was also detected for baselines withnon-axisymmetric monument structure.The orientation of the detected horizontal displacement wascoherent with the direction of daily temperature variation(DTV)driven by direct solar radiation,whichindicates that the diurnal and semidiurnal signals are likely induced by MTE.The observed high-frequency MTE displacements,if not well modeled and removed,may propagate into spurious long-term signals and bias the velocity estimation in the daily GPS time series. 展开更多
关键词 Monument thermal effect Diurnal and semidiurnal signal Very short GPS baseline Monument difference
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基于改进Simple Baselines的人体姿态估计算法
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作者 周昆阳 赵梦婷 +1 位作者 张海潮 蒋雯 《电脑与电信》 2021年第3期21-25,共5页
人体姿态估计在很多领域有着十分广泛的应用。为了提高人体姿态估计准确率,提出一种基于Simple Baselines的人体姿态估计算法。首先,将Simple Baselines的特征提取网络ResNet152替换为FastHand算法中的特征提取网络,提高模型检测准确率... 人体姿态估计在很多领域有着十分广泛的应用。为了提高人体姿态估计准确率,提出一种基于Simple Baselines的人体姿态估计算法。首先,将Simple Baselines的特征提取网络ResNet152替换为FastHand算法中的特征提取网络,提高模型检测准确率。其次,引进姿态修正机以提高模型对人体关节点定位准确率。实验结果表明,在COCO test-dev上,模型达到75.8%的AP,相较于Simple Baselines,AP提高2.1%。 展开更多
关键词 人体姿态估计 Simple baselines 姿态修正机 FastHand ResNet152
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基于ESI中全球论文影响力基准值(Baselines)的科研论文奖励政策分析
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作者 于洋 《产业与科技论坛》 2018年第5期123-124,共2页
ESI(Essential Science Indicators,基本科学指标数据库)是现阶段较为认可的评价高等学校、科研机构、国家或地区的科研水平及国际学术影响力的评价分析工具,ESI数据库是基于SCIE/SSCI所收录的10,000多种学术期刊及上千万条文献记录而... ESI(Essential Science Indicators,基本科学指标数据库)是现阶段较为认可的评价高等学校、科研机构、国家或地区的科研水平及国际学术影响力的评价分析工具,ESI数据库是基于SCIE/SSCI所收录的10,000多种学术期刊及上千万条文献记录而建立的计量分析数据库。现阶段,各研究机构针对ESI推出的奖励办法基本只单纯涉及了论文的引用次数奖励,但忽视了ESI中不同学科之间的差异。本文提出的基于ESI中全球论文影响力基准值(Baselines)的科研论文奖励思想,可以有效避免不同ESI学科之间论文引用次数存在较大差异的现象。 展开更多
关键词 ESI baselines 引用奖励
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Subtracting Technique of Baselines for Capillary Electrophoresis Signals
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作者 WANGYing MOJin-yuan +1 位作者 CHENZuan-guang GAOYan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第2期134-137,共4页
The drifting baselines of capillary electrophoresis affect the veracity of analysis greatly. This paper presents Threshold Fitting Technique(TFT) so as to subtract the baselines from the original signals and emendate ... The drifting baselines of capillary electrophoresis affect the veracity of analysis greatly. This paper presents Threshold Fitting Technique(TFT) so as to subtract the baselines from the original signals and emendate the signals. In TFT, wavelet and curve fitting technique are applied synthetically, thresholds are decided by the computer automatically. Many experiments of signal processing indicate that TFT is simple for being used, there are few man-induced factors, and the results are satisfactory. TFT can be applied for noisy signals without any pre-processing. 展开更多
关键词 BASELINE Capillary electrophoresis(CE) Curve fitting WAVELET THRESHOLD
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Multi-GNSS Fusion Real-Time Kinematic Algorithm Based on Extended Kalman Filter Correction Model for Medium-Long Baselines
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作者 XIA Yang REN Guanghui +1 位作者 WAN Yuan MAO Xuchu 《Journal of Shanghai Jiaotong university(Science)》 2024年第6期1191-1201,共11页
In the case of a medium-long baseline, for real-time kinematic (RTK) positioning, the fixed rate of integer ambiguity is low due to the distance between the base station and the observation station. Moreover, the atmo... In the case of a medium-long baseline, for real-time kinematic (RTK) positioning, the fixed rate of integer ambiguity is low due to the distance between the base station and the observation station. Moreover, the atmospheric delay after differential processing cannot be ignored. For correcting the residual atmospheric errors, we proposed a GPS/BDS/Galileo/GLONASS four-system fusion RTK positioning algorithm, which is based on the extended Kalman filter (EKF) algorithm. After realizing the spatio-temporal unification of multiple global navigation satellite systems (GNSSs), we introduced a parameter estimation of atmospheric errors based on the EKF model, using the least-squares integer ambiguity decorrelation adjustment (LAMBDA) to calculate the integer ambiguity. After conducting experiments for different baselines, the proposed RTK positioning algorithm can achieve centimeter-level positioning accuracy in the case of medium-long baselines. In addition, the time required to solve the fixed solution is shorter than that of the traditional RTK positioning algorithm. 展开更多
关键词 real-time kinematic(RTK) extended Kalman filter(EKF) BASELINE AMBIGUITY ionospheric delay tropospheric delay
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Quantifying methane emission baselines with high-resolution satellite data to support China’s emission control
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作者 Huiru Zhong Lu Shen +3 位作者 Meng Qu Yang Ou Yuzhong Zhang Huiqin Mao 《Science Bulletin》 2025年第14期2255-2259,共5页
Methane(CH4)is a very potent greenhouse gas with a globalwarming potential of approximately 80 times that of carbon dioxide(CO_(2))on a decadal scale[1].By November 2024,159 countrieshave signed the Global Methane Ple... Methane(CH4)is a very potent greenhouse gas with a globalwarming potential of approximately 80 times that of carbon dioxide(CO_(2))on a decadal scale[1].By November 2024,159 countrieshave signed the Global Methane Pledge,committing to reduceanthropogenic emissions by at least 30%by 2030 relative to the 2020 level(https://www.globalmethanepledge.org).In November2023,the Chinese government released an action plan dedicatedto methane emission control,including specific targets in differentsource sectors(https://www.mee.gov.cn/).However,large discrepancies still exist in China’s current methane inventories,hinderingthe setting of mitigation goals.By now,the national anthropogenicmethane emission estimates still vary by at least 30%,and sectoralemission estimates may differ by a factor of 2–5(Fig.1).To supportChina’s methane emission control plan,a key priority is to determine the emission baselines,which this work aims to address. 展开更多
关键词 carbon dioxide co BASELINE China methane emission satellite data Global Methane Pledge greenhouse gas action plan
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Emission Baselines for Clean Development Mechanism Projects: Residential Heating Case in Beijing
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作者 郭京菲 马玉清 《Tsinghua Science and Technology》 EI CAS 2000年第3期328-332,共5页
To explore emission baseline, technically the most difficult issue for Clean Development Mechanism (CDM) project development, as well as to examine whether CDM is a possible way to help Beijing restructure its heating... To explore emission baseline, technically the most difficult issue for Clean Development Mechanism (CDM) project development, as well as to examine whether CDM is a possible way to help Beijing restructure its heating energy consumption, this paper conducts a CDM baseline case study on residential heating in Beijing. Based on investigation, energy consumption forecast and economic analysis of future technology options, the technology benchmark and site specific baselines for both retrofit projects and new heating projects have been discussed. The results indicate that fuel switching from coal to natural gas can meet the additionality criteria in many cases and will be the main type of CDM project. In addition, it also proves that the technology benchmark and the case by case baseline setting approach are applicable for future CDM cooperation projects on heating in Beijing. 展开更多
关键词 clean development mechanism district heating baseline determination
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Standards as the foundation of innovation and cooperation
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作者 Christopher Millward 《China Standardization》 2025年第5期43-43,共1页
Basic communication standards that we rely upon reduce friction for consumers,customers and businesses,speed innovation and allow for cross-border collaboration among companies.That is critical for establishing global... Basic communication standards that we rely upon reduce friction for consumers,customers and businesses,speed innovation and allow for cross-border collaboration among companies.That is critical for establishing global baselines of trust.What standards can do that politics cannot is to bring people together,encourage collaboration,and encourage trusting relationships and the ability to share and develop interoperable communication systems.Today we are building roads that lead to quantum technologies,artificial intelligence and blockchain technologies,but the rules of those roads are yet to be written.The industry has an important role to play in developing rules of the road.Those rules need to start with a very basic foundation,such as data identification secured by design standards,standards for privacy protection,and watermarking,tracing and accountability of AI technologies and algorithms.These are all very achievable objectives,and they form together a foundation of trust that customers and governments worldwide can rely upon. 展开更多
关键词 STANDARDS INNOVATION establishing global baselines trustwhat communication standards communication quantum technologiesartificial friction bring people
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Baseline establishment,susceptibility monitoring and risk assessment of cyproflanilide,a novel meta-diamide insecticide,against Chilo suppressalis(Lepidoptera:Crambidae)in China
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作者 Wenchao Ge Songtao Qiao +7 位作者 Chong Liu Fangrui Guo Shuai Wang Hao Sun Yan Liu Fengxia Yang Shunfan Wu Congfen Gao 《Journal of Integrative Agriculture》 2025年第11期4342-4354,共13页
The rice stem borer,Chilo suppressalis(Walker)(Lepidoptera:Crambidae),is one of the most serious pests in rice-growing areas,and it has developed resistance to most insecticides currently used in the field.Cyproflanil... The rice stem borer,Chilo suppressalis(Walker)(Lepidoptera:Crambidae),is one of the most serious pests in rice-growing areas,and it has developed resistance to most insecticides currently used in the field.Cyproflanilide is a novel meta-diamide insecticide that has shown high activities to multiple pests.Evaluating the risk of resistance to cyproflanilide in C.suppressalis is necessary for its preventive resistance management.Here we established the baseline susceptibility of C.suppressalis to cyproflanilide by the rice-seedling dipping method and topical application,and the LC_(50) and LD_(50) values were 0.026 mg L^(-1) and 0.122 ng/larva,respectively.The LC_(50) values of cyproflanilide in 37 field populations ranged from 0.012 to 0.061 mg L^(-1),and 25 field populations exhibited resistance to chlorantraniliprole with the highest LC_(50) value of 3,770.059 mg L^(-1).In addition,a logistic distribution model analysis indicated that only 0.048 mg L^(-1) of cyproflanilide was required to kill 90% field chlorantraniliprole-resistant populations of C.suppressalis,compared to 2,087.764 mg L^(-1) of chlorantraniliprole for a similar level of control.Resistance screening over 19 generations did not result in resistance to cyproflanilide(RR=3.1-fold).The realized heritability(h^(2))of resistance was estimated as 0.067 by using threshold trait analysis,suggesting a low risk of cyproflanilide resistance development in susceptible strains.The Cypro-SEL population(F_(10))had no obvious fitness cost(relative fitness=0.96),and no significant changes in sensitivity to seven tested insecticides.These findings suggested that cyproflanilide is a promising insecticide for the management of chlorantraniliprole-resistant C.suppressalis.Moreover,this integrated risk assessment provides scientific application guidelines for the sustainable resistance management of cyproflanilide for controlling C.suppressalis. 展开更多
关键词 cyproflanilide Chilo suppressalis susceptibility baseline risk assessment realized heritability
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Constructing Optimal Baseline Designs from Regular Designs
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作者 Shiyu Li 《Open Journal of Applied Sciences》 2025年第2期463-479,共17页
This paper delves into the baseline design under the baseline parameterization model in experimental design, focusing on the relationship between the K-aberration criterion and the word length pattern (WLP) of regular... This paper delves into the baseline design under the baseline parameterization model in experimental design, focusing on the relationship between the K-aberration criterion and the word length pattern (WLP) of regular two-level designs. The paper provides a detailed analysis of the relationship between K5and the WLP for regular two-level designs with resolution t=3, and proposes corresponding theoretical results. These results not only theoretically reveal the connection between the orthogonal parameterization model and the baseline parameterization model but also provide theoretical support for finding the K-aberration optimal regular two-level baseline designs. It demonstrates how to apply these theories to evaluate and select the optimal experimental designs. In practical applications, experimental designers can utilize the theoretical results of this paper to quickly assess and select regular two-level baseline designs with minimal K-aberration by analyzing the WLP of the experimental design. This allows for the identification of key factors that significantly affect the experimental outcomes without frequently changing the factor levels, thereby maximizing the benefits of the experiment. 展开更多
关键词 Baseline Parameterization K-Aberration Criterion Regular Design Word Length Pattern
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Large-scale and long-term spatiotemporal patterns of disturbances in primary beech-dominated forests in the Carpathian Mountains of Europe
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作者 Pavel Janda Arne Buechling +22 位作者 Marek Svitok Thomas A.Nagel Martin Mikolas Radek Bace Kresimir Begovic Martin Dusatko Daniela Duhova Matej Ferencik Michal Frankovic Rhiannon Gloor Ondrej Kameniar Tomas Knir Daniel Kozak Jana Agh Labusova Katarina Markuljakova Jakob Pavlin Ion Catalin Petritan Catalin-Constantin Roibu Audrey Rose Salerno Karol Ujhazy Antonin Veber Lucie Vitkova Miroslav Svoboda 《Forest Ecosystems》 2025年第5期987-997,共11页
Extreme disturbance activity is a signature of anthropogenic environmental change. Empirical information describing the historical normative limits of disturbance regimes provides baseline data that facilitates the de... Extreme disturbance activity is a signature of anthropogenic environmental change. Empirical information describing the historical normative limits of disturbance regimes provides baseline data that facilitates the detection of contemporary trends in both disturbances and community-level responses. Quantifying the attributes of historical disturbances is challenging due to their transient episodic nature, with decades-to centurieslong intervals between recurrences. Unmanaged primary forests that support centuries-old trees therefore serve as unique reference systems for quantifying past disturbance regimes. We surveyed relict stands of primary beech-dominated forests over wide environmental gradients in the Carpathian Mountains of Europe. We collected core samples from 3,026 trees in 208 field survey plots distributed across 13 forest stands in two countries. We used dendrochronological methods to analyze time-series of annually-resolved ring-width variation and to identify anomalous growth patterns diagnostic of past forest canopy removal. A 180-year record(1810–1990) of spatially and temporally explicit disturbance events(n =333) was compiled and used to derive s tatistical attributes of the disturbance regime. We quantified disturbance severity(canopy area lost), patch size, and return intervals. Our analyses describe a complex regime where a background of relatively frequent, smallscale, low-to intermediate-severity disturbance was punctuated by episodic large-scale high-severity events. Even the most severe events were non-catastrophic at a stand level, leaving significant residual tree cover that supported a continuity of ecological function. We did not detect evidence for an expected climate-induced intensification of disturbance with time, but methodological limitations precluded an assessment of disturbance activity in the decades since 1990. 展开更多
关键词 Canopy gap Climate change Disturbance regime Ecosystem resilience Natural range of variability Baseline conditions Tree mortality
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Toroidal torques due to n=1 magnetic perturbations in ITER baseline scenario
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作者 Jingwei LI Li LI +5 位作者 Yueqiang LIU Yunfeng LIANG Yanfei WANG Lu TIAN Zhongqing LIU Fangchuan ZHONG 《Plasma Science and Technology》 2025年第1期39-51,共13页
Toroidal torques,generated by the resonant magnetic perturbation(RMP)and acting on the plasma column,are numerically systematically investigated for an ITER baseline scenario.The neoclassical toroidal viscosity(NTV),i... Toroidal torques,generated by the resonant magnetic perturbation(RMP)and acting on the plasma column,are numerically systematically investigated for an ITER baseline scenario.The neoclassical toroidal viscosity(NTV),in particular the resonant portion,is found to provide the dominant contribution to the total toroidal torque under the slow plasma flow regime in ITER.While the electromagnetic torque always opposes the plasma flow,the toroidal torque associated with the Reynolds stress enhances the plasma flow independent of the flow direction.A peculiar double-peak structure for the net NTV torque is robustly computed for ITER,as the toroidal rotation frequency is scanned near the zero value.This structure is found to be ultimately due to a non-monotonic behavior of the wave-particle resonance integral(over the particle pitch angle)in the superbanana plateau NTV regime in ITER.These findings are qualitatively insensitive to variations of a range of factors including the wall resistivity,the plasma pedestal flow and the assumed frequency of the rotating RMP field. 展开更多
关键词 toroidal torques resonant magnetic perturbation fieds plasma flow ITER baseline scenario
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Regional geochemical baseline establishment,heavy metal pollution assessment and investigation of its variation in response to human activities in mangrove intertidal sediments in Hainan,China
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作者 Fang LU Yong CHEN +1 位作者 Wenquan LIU Jichao YANG 《Journal of Oceanology and Limnology》 2025年第6期1792-1808,共17页
The intertidal zone of mangroves has a significant impact on the ecological environment by serving as a crucial habitat for a wide range of organisms.When assessing heavy metal contamination in sediments within this z... The intertidal zone of mangroves has a significant impact on the ecological environment by serving as a crucial habitat for a wide range of organisms.When assessing heavy metal contamination in sediments within this zone,it is essential to establish a regional geochemical baseline that accounts for natural variations.In this study,regional geochemical baselines of heavy metals were established based on core sediment samples collected from Dongzhai Harbor in November 2015.Linear regression analysis was employed to examine the correlations between heavy metals and potential normalized elements.Subsequently,the sediment quality and intensity of pollutant input in the sediments of a mangrove intertidal zone were evaluated with enrichment factor(EF)and excessive influx of heavy metals.The EF values for Cr,Cd,Pb,Zn,and Ni in the study area were all below 1.5,indicating minimal levels of contamination;however,minor Cu contamination was observed in the high tidal flat area due to potential terrestrial inputs.These findings suggest that the overall environmental quality about heavy metals was good within the intertidal zone of mangroves.Moreover,as for the excess fluxes of heavy metals in intertidal sediments,there was consistency between influence and intervention of human activities on sedimentary environment during the selected period when examining variation trends. 展开更多
关键词 mangrove intertidal zone SEDIMENT geochemical baseline heavy metal contamination risk assessment
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Numerical simulation for large baseline interferometric imaging altimeter
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作者 Jie Liu Bo Liu +2 位作者 Xiaonan An Haifeng Kou Bing Li 《Geodesy and Geodynamics》 2025年第1期111-126,共16页
Sea topography information holds significant importance in oceanic research and the climate change detection.Radar imaging altimetry has emerged as the leading approach for global ocean observation,employing synthetic... Sea topography information holds significant importance in oceanic research and the climate change detection.Radar imaging altimetry has emerged as the leading approach for global ocean observation,employing synthetic aperture radar(SAR)interferometry to enhance the spatial resolution of Sea topography.Nevertheless,current payload capacity and satellite hardware limitations prevent the extension of the interferometric baseline by enlarging the physical antenna size.This constraint hinders achieving centimeter-level accuracy in interferometric altimetry.To address this challenge,we conducted a numerical simulation to assess the viability of a large baseline interferometric imaging altimeter(LB-IIA).By controlling the baseline within the range of 600-1000 m through spiral orbit design in two satellites and mitigating baseline de-correlation with the carrier frequency shift(CFS)technique,we aimed to overcome the above limitations.Our findings demonstrate the efficacy of the CFS technique in compensating for baseline decoherence,elevating coherence from less than 0.1 to over 0.85.Concurrently.The height difference accuracy between neighboring sea surfaces reaches 1 cm within a 1 km resolution.This study is anticipated to serve as a foundational reference for future interferometric imaging altimeter development,catering to the demand for high-precision sea topography data in accurate global bathymetry inversion. 展开更多
关键词 Sea topography Numerical simulation Carrier frequency shift(CFS) Large baseline interferometric imaging altimeter(LB-IIA)
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A novel baseline perspective visibility graph for time series analysis
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作者 Huang-Jing Ni Zi-Jie Song +3 位作者 Jiao-Long Qin Ye Wu Shi-Le Qi Ming Song 《Chinese Physics B》 2025年第8期530-538,共9页
The natural visibility graph method has been widely used in physiological signal analysis,but it fails to accurately handle signals with data points below the baseline.Such signals are common across various physiologi... The natural visibility graph method has been widely used in physiological signal analysis,but it fails to accurately handle signals with data points below the baseline.Such signals are common across various physiological measurements,including electroencephalograph(EEG)and functional magnetic resonance imaging(fMRI),and are crucial for insights into physiological phenomena.This study introduces a novel method,the baseline perspective visibility graph(BPVG),which can analyze time series by accurately capturing connectivity across data points both above and below the baseline.We present the BPVG construction process and validate its performance using simulated signals.Results demonstrate that BPVG accurately translates periodic,random,and fractal signals into regular,random,and scale-free networks respectively,exhibiting diverse degree distribution traits.Furthermore,we apply BPVG to classify Alzheimer’s disease(AD)patients from healthy controls using EEG data and identify non-demented adults at varying dementia risk using resting-state fMRI(rs-fMRI)data.Utilizing degree distribution entropy derived from BPVG networks,our results exceed the best accuracy benchmark(77.01%)in EEG analysis,especially at channels F4(78.46%)and O1(81.54%).Additionally,our rs-fMRI analysis achieves a statistically significant classification accuracy of 76.74%.These findings highlight the effectiveness of BPVG in distinguishing various time series types and its practical utility in EEG and rs-fMRI analysis for early AD detection and dementia risk assessment.In conclusion,BPVG’s validation across both simulated and real data confirms its capability to capture comprehensive information from time series,irrespective of baseline constraints,providing a novel method for studying neural physiological signals. 展开更多
关键词 baseline perspective visibility graph degree distribution entropy time series analysis
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SBAS-InSAR技术监测青藏高原季节性冻土形变 被引量:129
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作者 李珊珊 李志伟 +2 位作者 胡俊 孙倩 俞晓莹 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2013年第5期1476-1486,共11页
冻土的冻结和融化的反复交替会造成地质环境与结构的破坏,从而导致房屋和道路等地面工程建筑物的地基破裂或者塌陷,还会引起山体滑坡、洪水暴发以及冰川移动等.因此,监测冻土形变对确保冻土区工程建筑的稳定性和安全性,同时保证冻土区... 冻土的冻结和融化的反复交替会造成地质环境与结构的破坏,从而导致房屋和道路等地面工程建筑物的地基破裂或者塌陷,还会引起山体滑坡、洪水暴发以及冰川移动等.因此,监测冻土形变对确保冻土区工程建筑的稳定性和安全性,同时保证冻土区社会经济可持续发展具有重要的意义.目前,在冻土监测方面并没有能大面积监测冻土形变时间演化情况的有效方法,本文提出将InSAR技术中的小基线集方法(SBAS-InSAR)应用于监测冻土来获取其形变时间序列中.考虑到冻土形变呈现明显的季节性特征,本文提出利用周期形变模型来代替传统SBAS方法中的线性形变模型,从而更好地分离出高程残差和大气误差.利用ENVISAT卫星获取的21景ASAR影像图作为实验数据,采用改进的SBAS技术成功获取了青藏高原从羊八井站至当雄站铁路段冻土区的地表形变时间序列图,揭示了该冻土区从2007年到2010年的季节性形变演化情况.通过与研究地区温度变化的联合分析,发现所得到的地表形变结果与冻土的物理变化规律非常吻合,证明了SBAS-InSAR技术在冻土形变监测中具有良好的发展应用前景. 展开更多
关键词 冻土 INSAR SBAS (Small BASELINE subset) 青藏高原 形变监测
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基于短基线集方法(SBAS-INSAR)技术的山区城市地面沉降监测研究——以攀枝花为例 被引量:21
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作者 孟庆凯 汪宝存 苗放 《科学技术与工程》 北大核心 2016年第13期12-17,共6页
基于合成孔径雷达干涉(interferometric synthetic aperture radar,INSAR)技术的山区城市地面沉降研究,因地形复杂、植被覆盖等因素开展较少。首次在攀枝花市,利用12景2009-2010ENVISAT ASAR数据,采用短基线集方法开展大范围、长时间监... 基于合成孔径雷达干涉(interferometric synthetic aperture radar,INSAR)技术的山区城市地面沉降研究,因地形复杂、植被覆盖等因素开展较少。首次在攀枝花市,利用12景2009-2010ENVISAT ASAR数据,采用短基线集方法开展大范围、长时间监测。结果表明,攀枝花市东区地面沉降较大,沉降的平均速率高达48 mm/年;西区沉降较小,沉降平均速率10 mm/年。推测原因多为城市化建设所致地面荷载;而市东北方向的露天矿区,因连续开采所致,不同时期同一地点的地表变化,导致高相干点在此区域分散稀疏,不能表明是否有沉降现象。 展开更多
关键词 地面沉降 短基线集(sinall BASELINE subset SBAS) 时序分析 攀枝花
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Finite element model updating and validating of Runyang Suspension Bridge based on SHMS 被引量:7
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作者 王浩 李爱群 缪长青 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期474-479,共6页
Based on the finite element (FE) program ANSYS, a three-dimensional model for the Runyang Suspension Bridge (RSB) is established. The structural natural frequency, vibration mode, stress and displacement response ... Based on the finite element (FE) program ANSYS, a three-dimensional model for the Runyang Suspension Bridge (RSB) is established. The structural natural frequency, vibration mode, stress and displacement response under various load cases are given. A new method of FE model updating is presented based on the physical meaning of sensitivity and the penalty function concept. In this method, the structural model is updated by modifying the parameters of design, and validated by structural natural vibration characteristics, stress response as well as displacement response. The design parameters used for updating are bounded according to measured static response and engineering judgment. The FE model of RSB is updated and validated by the measurements coming from the structural health monitoring system (SHMS), and the FE baseline model reflecting the current state of RSB is achieved. Both the dynamic and static results show that the method is effective in updating the FE model of long span suspension bridges. The results obtained provide an important research basis for damage alarming and health monitoring of the RSB. 展开更多
关键词 suspension bridge finite element model updating model validating baseline model structural health monitoring system (SHMS)
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Cooperative navigation and localization for multiple UUVs 被引量:4
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作者 张立川 徐德民 +1 位作者 刘明雍 严卫生 《Journal of Marine Science and Application》 2009年第3期216-221,共6页
The authors proposed a moving long baseline algorithm based on the extended Kalman filter (EKF) for cooperative navigation and localization of multi-unmanned underwater vehicles (UUVs). Research on cooperative nav... The authors proposed a moving long baseline algorithm based on the extended Kalman filter (EKF) for cooperative navigation and localization of multi-unmanned underwater vehicles (UUVs). Research on cooperative navigation and localization for multi-UUVs is important to solve navigation problems that restrict long and deep excursions. The authors investigated improvements in navigation accuracy. In the moving long base line (MLBL) structure, the master UUV is equipped with a high precision navigation system as a node of the moving long baseline, and the slave UUV is equipped with a low precision navigation system. They are both equipped with acoustic devices to measure relative location. Using traditional triangulation methods to calculate the position of the slave UUV may cause a faulty solution. An EKF was designed to solve this, combining the proprioceptive and exteroceptive sensors. Research results proved that the navigational accuracy is improved significantly with the MLBL method based on EKF. 展开更多
关键词 navigation system moving long baseline multi-UUVs cooperative navigation and localization extended Kalman filter (EKF)
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Baseline Sensitivity of Botrytis cinerea from Liaoning Province to Boscalid 被引量:3
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作者 刘妍 祁之秋 +2 位作者 韩宝艳 赵铂锤 纪明山 《Agricultural Science & Technology》 CAS 2015年第11期2531-2534,共4页
[Objective] This study aimed to avoid and delay the generation of resis- tance in Botrytis cinerea to boscalid. [Method] The sensitivity of Botrytis cinerea to boscalid was tested by the mycelial growth rate method. T... [Objective] This study aimed to avoid and delay the generation of resis- tance in Botrytis cinerea to boscalid. [Method] The sensitivity of Botrytis cinerea to boscalid was tested by the mycelial growth rate method. The distribution of sensitivity variation of B. cinerea to boscalid in different regions was cleared, and the sen- sitivity baseline of B. cinerea from Liaoning Province to boscalid was established. [Result] The ECso values of B. cinerea strains from Liaoning Province ranged from 0.080 0 to 7.787 2μg/ml, and the highest ECho value was 97.34 times higher than the minimum. The average EC50 value (1.973μg/ml) of the 158 strains was treated as the baseline sensitivity of B. cinerea from Liaoning Province to boscalid. [Conclu- sion] It is essential to conduct a risk assessment of drug resistance in B. cinerea to boscalid. 展开更多
关键词 TOMATO Botrytis cinerea BOSCALID Sensitivity Baseline sensitivity
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