期刊文献+
共找到50,636篇文章
< 1 2 250 >
每页显示 20 50 100
远程污染自动监测报警物联网通信系统设计
1
作者 李万军 《自动化与仪器仪表》 2019年第3期144-146,共3页
在现代通信技术不断发展的过程中,物联网技术被广泛应用到多领域中,并且也为解决现代污染自动检测报警问题提出了全新的思路。基于物联网的远程污染自动监测报警联网通信系统实现传感网、计算机网络及无线网络的相互结合,能够及时监测污... 在现代通信技术不断发展的过程中,物联网技术被广泛应用到多领域中,并且也为解决现代污染自动检测报警问题提出了全新的思路。基于物联网的远程污染自动监测报警联网通信系统实现传感网、计算机网络及无线网络的相互结合,能够及时监测污染,并且还能够同步报警,提高了监测报警可靠性。 展开更多
关键词 远程 污染自动监测报警 物联网 通信系统
Potential Bands of Sentinel-2A Satellite for Classification Problems in Precision Agriculture
2
作者 Tian-Xiang Zhang Jin-Ya Su +1 位作者 Cun-Jia Liu Wen-Hua Chen 《国际自动化与计算杂志:英文版》 EI CSCD 2019年第1期16-26,共11页
Various indices are used for assessing vegetation and soil properties in satellite remote sensing applications.Some indices,such as normalized difference vegetation index(NDVI)and normalized difference water index(NDW... Various indices are used for assessing vegetation and soil properties in satellite remote sensing applications.Some indices,such as normalized difference vegetation index(NDVI)and normalized difference water index(NDWI),are capable of simply differentiating crop vitality and water stress.Nowadays,remote sensing capabilities with high spectral,spatial and temporal resolution are available to analyse classification problems in precision agriculture.Many challenges in precision agriculture can be addressed by supervised classification,such as crop type classification,disease and stress(e.g.,grass,water and nitrogen)monitoring.Instead of performing classification based on designated indices,this paper explores direct classification using different bands information as features.Land cover classification by using the recently launched Sentinel-2A image is adopted as a case study to validate our method.Four approaches of featured band selection are compared to classify five classes(crop,tree,soil,water and road)with the support vector machines(SVMs)algorithm,where the first approach utilizes traditional empirical indices as features and the latter three approaches adopt specific bands(red,near infrared and short wave infrared)related to indices,specific bands after ranking by mutual information(MI),and full bands of on-board sensors as features,respectively.It is shown that a better classification performance can be achieved by directly using the selected bands after MI ranking compared with the one using empirical indices and specific bands related to indices,while the use of all 13 bands can marginally improve the classification accuracy than MI based one.Therefore,it is recommended that this approach can be applied for specific Sentinel-2A image classification problems in precision agriculture. 展开更多
关键词 Sentinel-2A REMOTE SENSING image classification supervised learning precision AGRICULTURE
智能电子捕鼠器及远程管理平台的研究 预览
3
作者 李慧勤 陈少凡 +1 位作者 谢江林 郑丽榕 《科技创新与应用》 2019年第6期183-184,共2页
本研究为解决目前捕鼠器捕获率低和捕获后无人知晓导致动物死亡,死亡后动物将在捕鼠笼中留下浓密的动物气味将影响第二次的动物捕获。本研究产品智能投放引诱饵料可提高捕鼠成功率,可在捕获同时通过2G/3G/4G蜂窝模组连接至互联网云端,... 本研究为解决目前捕鼠器捕获率低和捕获后无人知晓导致动物死亡,死亡后动物将在捕鼠笼中留下浓密的动物气味将影响第二次的动物捕获。本研究产品智能投放引诱饵料可提高捕鼠成功率,可在捕获同时通过2G/3G/4G蜂窝模组连接至互联网云端,云端物联网平台使用微信公众号平台或者短信以及电话报警,提醒工作人员此捕鼠器的需清理维护。 展开更多
关键词 智能 电子 远程 平台化 长效
在线阅读 下载PDF
Smart Photogrammetric and Remote Sensing Image Processing for Very High Resolution Optical Images——Examples from the CRC-AGIP Lab at UNB 预览
4
作者 Yun ZHANG 《测绘学报(英文版)》 2019年第2期17-26,共10页
This paper introduces some of the image processing techniques developed in the Canada Research Chair in Advanced Geomatics Image Processing Laboratory (CRC-AGIP Lab) and in the Department of Geodesy and Geomatics Engi... This paper introduces some of the image processing techniques developed in the Canada Research Chair in Advanced Geomatics Image Processing Laboratory (CRC-AGIP Lab) and in the Department of Geodesy and Geomatics Engineering (GGE) at the University of New Brunswick (UNB), Canada. The techniques were developed by innovatively/“smartly” utilizing the characteristics of the available very high resolution optical remote sensing images to solve important problems or create new applications in photogrammetry and remote sensing. The techniques to be introduced are: automated image fusion (UNB-PanSharp), satellite image online mapping, street view technology, moving vehicle detection using single set satellite imagery, supervised image segmentation, image matching in smooth areas, and change detection using images from different viewing angles. Because of their broad application potential, some of the techniques have made a global impact, and some have demonstrated the potential for a global impact. 展开更多
关键词 remote sensing optical IMAGE very high resolution pan-sharpening online mapping STREET view moving information DETECTION IMAGE SEGMENTATION IMAGE MATCHING change DETECTION
在线阅读 免费下载
Remote sensing and geographic information systems techniques in studies on treeline ecotone dynamics 预览
5
作者 Parveen K.Chhetri Eric Thai 《林业研究:英文版》 CAS CSCD 2019年第5期1543-1553,共11页
We performed a meta-analysis on over 100 studies applying remote sensing(RS)and geographic information systems(GIS)to understand treeline dynamics.A literature search was performed in multiple online databases,includi... We performed a meta-analysis on over 100 studies applying remote sensing(RS)and geographic information systems(GIS)to understand treeline dynamics.A literature search was performed in multiple online databases,including Web of Knowledge(Thomson Reuters),Scopus(Elsevier),BASE(Bielefeld Academic Search Engine),CAB Direct,and Google Scholar using treeline-related queries.We found that RS and GIS use has steadily increased in treeline studies since 2000.Spatialresolution RS and satellite imaging techniques varied from low-resolution MODIS,moderate-resolution Landsat,to high-resolution WorldView and aerial orthophotos.Most papers published in the 1990s used low to moderate resolution sensors such as Landsat Multispectral Scanner and Thematic Mapper,or SPOT PAN(Panchromatic)and MX(Multispectral)RS images.Subsequently,we observed a rise in high-resolution satellite sensors such as ALOS,GeoEye,IKONOS,and WorldView for mapping current and potential treelines.Furthermore,we noticed a shift in emphasis of treeline studies over time:earlier reports focused on mapping treeline positions,whereas RS and GIS are now used to determine the factors that control treeline variation. 展开更多
关键词 Digital ELEVATION model GEOGRAPHIC information systems Remote SENSING TREELINE
在线阅读 下载PDF
工业APP的远程协同运维系统在铝合金轮毂生产线上的应用
6
作者 陈庚 李利清 王世东 《机械设计》 CSCD 北大核心 2019年第A01期336-339,共4页
一般设备制造商很难掌握重型机械设备在用户现场的使用情况,设备一旦出现问题,工程技术人员很难根据用户现场操作人员的描述找到问题的根源并及时有效地排除故障。为了解决上述问题,文中介绍了一种可以应用在铝合金轮毂生产线上的工业AP... 一般设备制造商很难掌握重型机械设备在用户现场的使用情况,设备一旦出现问题,工程技术人员很难根据用户现场操作人员的描述找到问题的根源并及时有效地排除故障。为了解决上述问题,文中介绍了一种可以应用在铝合金轮毂生产线上的工业APP的远程协同运维系统。该系统使用移动互联网实现对用户现场设备的在线监控与管理。 展开更多
关键词 铝合金轮毂生产线 工业APP 远程 运维系统 移动互联网
Modeling and predicting dengue fever cases in key regions of the Philippines using remote sensing data
7
作者 Maria Ruth B.Pineda-Cortel Benjie M.Clemente Pham Thi Thanh Nga 《亚太热带医药杂志:英文版》 SCIE CAS 2019年第2期60-66,共7页
Objective: To correlate climatic and environmental factors such as land surface temperature, rainfall, humidity and normalized difference vegetation index with the incidence of dengue to develop prediction models for ... Objective: To correlate climatic and environmental factors such as land surface temperature, rainfall, humidity and normalized difference vegetation index with the incidence of dengue to develop prediction models for the Philippines using remote-sensing data.Methods: Timeseries analysis was performed using dengue cases in four regions of the Philippines and monthly climatic variables extracted from Global Satellite Mapping of Precipitation for rainfall, and MODIS for the land surface temperature and normalized difference vegetation index from 2008-2015.Consistent dataset during the period of study was utilized in Autoregressive Integrated Moving Average models to predict dengue incidence in the four regions being studied.Results: The best-fitting models were selected to characterize the relationship between dengue incidence and climate variables.The predicted cases of dengue for January to December 2015 period fitted well with the actual dengue cases of the same timeframe.It also showed significantly good linear regression with a square of correlation of 0.869 5 for the four regions combined.Conclusion: Climatic and environmental variables are positively associated with dengue incidence and suit best as predictor factors using Autoregressive Integrated Moving Average models.This finding could be a meaningful tool in developing an early warning model based on weather forecasts to deliver effective public health prevention and mitigation programs. 展开更多
关键词 DENGUE FEVER Climate change REMOTE SENSING data AUTOREGRESSIVE Integrated Moving AVERAGE models
用于水下金属探测成像的压电式微机械超声波换能器 预览
8
作者 杨晋玲 《中国测试》 CAS 北大核心 2019年第9期84-88,共5页
为满足目前对水下金属、蛙人等检测的应用需要,设计一种用于水下金属探测成像的压电式微机械超声换能器。在该结构中,在顶部电极和下电级之间插入AlN层,用于发射和接收超声。当测试距离达到10 m以上就可以满足实际应用需求,而该换能器... 为满足目前对水下金属、蛙人等检测的应用需要,设计一种用于水下金属探测成像的压电式微机械超声换能器。在该结构中,在顶部电极和下电级之间插入AlN层,用于发射和接收超声。当测试距离达到10 m以上就可以满足实际应用需求,而该换能器经过实验得出最远的测试距离为12.8 m,且在12.8 m处测试值与理论值误差仅为0.67 cm,完全可以达到实际检测需要。在一个标准大气压下,利用微系统激光分析仪MSA400对该传感器进行膜位移测量,其测量值为0.28μm,与理论结果误差为1%。并且详细介绍该传感器的工艺实现过程。利用该传感器实现二维水下超声成像,证明水下存在金属矩形物体。该实验有利于水下超声成像系统的建立。 展开更多
关键词 PMUT C-V测试 超声成像 远距离
在线阅读 下载PDF
Towards reliable Arctic sea ice prediction using multivariate data assimilation
9
作者 Jiping Liu Zhiqiang Chen +11 位作者 Yongyun Hu Yuanyuan Zhang Yifan Ding Xiao Cheng Qinghua Yang Lars Nerger Gunnar Spreen Radley Horton Jun Inoue Chaoyuan Yang Ming Li Mirong Song 《科学通报:英文版》 SCIE EI CSCD 2019年第1期63-72,共10页
Rapid declines in Arctic sea ice have captured attention and pose significant challenges to a variety of stakeholders.There is a rising demand for Arctic sea ice prediction at daily to seasonal time scales,which is pa... Rapid declines in Arctic sea ice have captured attention and pose significant challenges to a variety of stakeholders.There is a rising demand for Arctic sea ice prediction at daily to seasonal time scales,which is partly a sea ice initial condition problem,Thus,a multivariate data assimilation that integrates sea ice observations to generate realistic and skillful model initialization is needed to improve predictive skill of Arctic sea ice.Sea ice data assimilation is a relatively new research area,In this review paper,we focus on two challenges for implementing multivariate data assimilation systems for sea ice forecast,First,to address the challenge of limited spatiotemporal coverage and large uncertainties of observations,we discuss sea ice parameters derived from satellite remote sensing that (1)have been utilized for improved model initialization,including concentration,thickness and drift,and (2)are currently under develop- ment with the potential for enhancing the predictability of Arctic sea ice,including melt ponds and sea ice leads.Second,to strive to generate the "best"estimate of sea ice initial conditions by combining model simulations]forecasts and observations,we review capabilities and limitations of different data assimilation techniques that have been developed and used to assimilate observed sea ice parameters in dynamical models. 展开更多
关键词 ARCTIC sea ice PREDICTION Remote sensing Data ASSIMILATION
The Influences and Measures on Children of Family Language Policy in Autocratic Family 预览
10
作者 TANG Hong 《海外英语》 2019年第14期106-110,共5页
As the smallest unit of social group, family language policy(FLP) plays a guide role, such as its making, implementationand evaluation are influenced among the family members and children’s grow-up. However, parents ... As the smallest unit of social group, family language policy(FLP) plays a guide role, such as its making, implementationand evaluation are influenced among the family members and children’s grow-up. However, parents who are in remote area thinkonly under their FLP can children obey them and be protected well. But the reality is that FLP in autocratic family has bad influence on children because of lacking science. In terms of the research on FLP, this thesis tries to analyze the effect and measures ofFLP in autocratic family on kids in remote rural areas according to language acquisition, intergenerational differences and bilingualinfluences which come from different writers or articles. 展开更多
关键词 remote rural areas autocratic family FLP measures
在线阅读 免费下载
Improving remote sensing-based net primary production estimation in the grazed land with defoliation formulation model
11
作者 YE Hui HUANG Xiao-tao +3 位作者 LUO Ge-ping WANG Jun-bang ZHANG Miao WANG Xin-xin 《山地科学学报:英文版》 SCIE CSCD 2019年第2期323-336,共14页
Remote sensing(RS) technologies provide robust techniques for quantifying net primary productivity(NPP) which is a key component of ecosystem production management. Applying RS, the confounding effects of carbon consu... Remote sensing(RS) technologies provide robust techniques for quantifying net primary productivity(NPP) which is a key component of ecosystem production management. Applying RS, the confounding effects of carbon consumed by livestock grazing were neglected by previous studies, which created uncertainties and underestimation of NPP for the grazed lands. The grasslands in Xinjiang were selected as a case study to improve the RS based NPP estimation. A defoliation formulation model(DFM) based on RS is developed to evaluate the extent of underestimated NPP between 1982 and 2011. The estimates were then used to examine the spatiotemporal patterns of the calculated NPP. Results show that average annual underestimated NPP was 55.74 gC·m-2yr-1 over the time period understudied, accounting for 29.06% of the total NPP for the Xinjiang grasslands. The spatial distribution of underestimated NPP is related to both grazing intensity and time. Data for the Xinjiang grasslands show that the average annual NPP was 179.41 gC·m-2yr-1, the annual NPP with an increasing trend was observed at a rate of 1.04 gC·m-2yr-1 between 1982 and 2011. The spatial distribution of NPP reveals distinct variations from high to low encompassing the geolocations of the Tianshan Mountains, northern and southern Xinjiang Province and corresponding with mid-mountain meadow, typical grassland, desert grassland, alpine meadow, and saline meadow grassland types. This study contributes to improving RS-based NPP estimations for grazed land and provides a more accurate data to support the scientific management of fragile grassland ecosystems in Xinjiang. 展开更多
关键词 Remote SENSING DEFOLIATION FORMULATION model Net primary production Grazed LAND Spatial-temporal patterns XINJIANG
Haptic based teleoperation with master-slave motion mapping and haptic rendering for space exploration
12
作者 Guanyang LIU Xuda GENG +1 位作者 Lingzhi LIU Yan WANG 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第3期723-736,共14页
This paper presents a new solution to haptic based teleoperation to control a large-sized slave robot for space exploration, which includes two specially designed haptic joysticks, a hybrid master-slave motion mapping... This paper presents a new solution to haptic based teleoperation to control a large-sized slave robot for space exploration, which includes two specially designed haptic joysticks, a hybrid master-slave motion mapping method, and a haptic feedback model rendering the operating resistance and the interactive feedback on the slave side. Two devices using the 3 R and DELTA mechanisms respectively are developed to be manipulated to control the position and orientation of a large-sized slave robot by using both of a user’s two hands respectively. The hybrid motion mapping method combines rate control and variable scaled position mapping to realize accurate and efficient master-slave control. Haptic feedback for these two mapping modes is designed with emphasis on ergonomics to improve the immersion of haptic based teleoperation. A stiffness estimation method is used to calculate the contact stiffness on the slave side and play the contact force rendered by using a traditional spring-damping model to a user on the master side stably. Experiments by using virtual environments to simulate the slave side are conducted to validate the effectiveness and efficiency of the proposed solution. 展开更多
关键词 TELEOPERATION HAPTIC device REMOTE control HAPTIC RENDERING Space EXPLORATION
能耗远程在线监测系统在工业节能中的应用 预览
13
作者 何召辉 罗孝美 孙翼 《上海节能》 2019年第8期714-716,共3页
为保证企业实现节能减排目标,设计和使用远程在线监测系统势在必行。远程在线监测系统是基于传感器与网络技术的优势,在企业区域各个位置针对性安装传感器,对实时数据进行采集、编码传输到远程管理系统。远程管理系统对采集的数据进行分... 为保证企业实现节能减排目标,设计和使用远程在线监测系统势在必行。远程在线监测系统是基于传感器与网络技术的优势,在企业区域各个位置针对性安装传感器,对实时数据进行采集、编码传输到远程管理系统。远程管理系统对采集的数据进行分析,计算出生产性能指标指导运行人员优化运行。 展开更多
关键词 工业 远程 在线 监测系统 技术
在线阅读 下载PDF
Three Decades of Sea-Ice Variability in Jiaozhou Bay Revealed by Landsat Observations 预览
14
作者 HUANG Jue GUO Lianjie +1 位作者 JIANG Tao ZHU Hongchun 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第2期349-357,共9页
In this study,we used Landsat images and meteorological data to examine the spatiotemporal distribution and variability of sea ice in Jiaozhou Bay(JZB)between 1986 and 2016.The results show that JZB is not always cove... In this study,we used Landsat images and meteorological data to examine the spatiotemporal distribution and variability of sea ice in Jiaozhou Bay(JZB)between 1986 and 2016.The results show that JZB is not always covered by sea ice in winter,but in some extreme cases,sea ice has covered more than one-third of the sea area of the bay.Sea ice in JZB has generally formed between January 1 and February 5,primarily along the coast,and gradually expanding to the central area of the bay.Both meteorological and artificial factors have played important roles in modulating the sea ice distribution.We found sea ice coverage to have been strongly correlated with the accumulated freezing-degree days nine days before the occurrence of sea ice(R2=0.767).North-northwest surface winds have dominated the freezing period of sea water in the JZB,and wind speed has exerted a more significant influence on the formation of sea ice when the sea ice coverage has been generally small.Additionally,artificial factors began to affect the expansion of sea ice in JZB since 2007.The construction of the Jiao-Zhou-Bay Bridge(JZBB)is believed to have retarded water flow and reduced the tidal prism,thereby leading to the formation of an ice bridge along the JZBB,which effectively prevents the southward expansion of sea ice. 展开更多
关键词 sea ice Jiaozhou BAY remote sensing LANDSAT
在线阅读 下载PDF
船载远程电子通信设备异常信号识别方法 预览
15
作者 刘雪春 《舰船科学技术》 北大核心 2019年第8期163-165,共3页
传统的船载远程电子通信设备异常信号识别方法存在着识别性能差的缺陷,为此提出船载远程电子通信设备异常信号识别方法研究。利用比较判别法对采集的船载远程电子通信设备信号进行判别,对异常信号特征进行提取并组成异常信号特征集合,... 传统的船载远程电子通信设备异常信号识别方法存在着识别性能差的缺陷,为此提出船载远程电子通信设备异常信号识别方法研究。利用比较判别法对采集的船载远程电子通信设备信号进行判别,对异常信号特征进行提取并组成异常信号特征集合,以异常信号特征集合为依据采用异常信号识别算法对异常信号进行识别,实现了船载远程电子通信设备异常信号的识别。通过实验得到,提出的船载远程电子通信设备异常信号识别方法识别正确率比传统方法高出24%,说明提出的船载远程电子通信设备异常信号识别方法具备更好的识别性能。 展开更多
关键词 船载 远程 电子通信设备 异常信号 识别
在线阅读 下载PDF
A study of the spatial-temporal distribution and propagation characteristics of internal waves in the Andaman Sea using MODIS 预览
16
作者 Lina Sun Jie Zhang Junmin Meng 《海洋学报:英文版》 SCIE CAS CSCD 2019年第7期121-128,共8页
This paper describes investigations of the internal waves in the Andaman Sea using Moderate Resolution Imaging Spectroradiometer(MODIS)imagery over the period of June 2010 to May 2016.Results of the spatial and tempor... This paper describes investigations of the internal waves in the Andaman Sea using Moderate Resolution Imaging Spectroradiometer(MODIS)imagery over the period of June 2010 to May 2016.Results of the spatial and temporal distribution,generation sources and propagation characteristics of internal waves are presented.The statistical analysis shows that internal waves can be observed in almost the entire area of the Andaman Sea.Most internal waves are observed in the northern,central and southern regions of the Andaman Sea.A significant number of internal waves between 7°N and 9°N in the East Indian Ocean are also observed.Internal waves can be observed year-round in the Andaman Sea,while most of internal waves are observed between February and April,with a maximum frequency of 15.03%in March.The seasonal distribution of the internal waves shows that the internal waves have mostly been observed in the dry season(February to April),and fewer internal waves are observed in the rainy season(May to October).The double peak distribution for the occurrence frequency of internal waves is found.With respect to the lunar influence,more internal waves are observed after the spring tide,which implies the spring tide may play an important role in internal wave generation in the Andaman Sea.Generation sources of internal waves are explored based on the propagation characteristics of internal waves.The results indicate that six sources are located between the Andaman Islands and the Nicobar Islands,and one is located in the northern Andaman Sea.Four regions with active internal wave phenomenon in the Andaman Sea were presented during the MODIS survey,and the propagation speed of internal waves calculated based on the semidiurnal generation period is smaller than the results acquired from pairs of the images with short time intervals. 展开更多
关键词 INTERNAL WAVES REMOTE SENSING Andaman SEA MODIS
在线阅读 下载PDF
Perspectives on mechanisms underlying remote ischemic conditioning against ischemic stroke 预览
17
作者 Changqing Xia Xunming Ji 《转化神经科学电子杂志(英文)》 2019年第1期1-14,共14页
Ischemic stroke is a major neurological disease with limited effective therapeutic options except for thrombolysis and thrombectomy. Remote ischemic conditioning (RIC) is an approach that promises an alternative to th... Ischemic stroke is a major neurological disease with limited effective therapeutic options except for thrombolysis and thrombectomy. Remote ischemic conditioning (RIC) is an approach that promises an alternative to the current treatment portfolio. As an easy-handled, non-invasive regimen, it takes advantage of transient ischemia (currently often made through inflation and deflation of limb blood pressure cuff) to enhance the tolerance of vital organs to ischemia. RIC can be executed before, during and after the onset of stroke. The mechanisms of action of RIC employed at different stroke stages are similar and may involve humoral, neurological and inflammatory pathways. As new mechanisms underlying RIC-induced neuroprotection continue to be revealed, we review in this article some of the latest development in this field, including:① RIC and RIC-induced fundamental change, hypoxia, as well as the role of hypoxia inducible factors against stroke;② Potential role of RIC-induced extracellular vesicles in neuroprotection;③ RIC-induced metabolic changes in tissue protection;④ Potential effect of RIC on red blood cells (RBC) oxygen delivery;and ⑤ RIC and its anti-inflammatory potential. 展开更多
关键词 REMOTE ISCHEMIC CONDITIONING (RIC) stroke hypoxia INDUCIBLE factors (HIF) EXOSOME oxygen delivery inflammation metabolomics microRNA
在线阅读 下载PDF
基于S7-1200的煤矿自动化排水系统设计
18
作者 唐辉辉 《煤矿机械》 北大核心 2019年第7期182-185,共4页
以PLC控制器作为核心,设计煤矿自动化排水系统,实现井下排水系统的自动化。通过交换机传递控制器处理过的传感器采集的信息,主机系统监控井下各设备的实时状态,并控制设备自动化运行。该系统具有自动、半自动、手动、远程等多种控制模... 以PLC控制器作为核心,设计煤矿自动化排水系统,实现井下排水系统的自动化。通过交换机传递控制器处理过的传感器采集的信息,主机系统监控井下各设备的实时状态,并控制设备自动化运行。该系统具有自动、半自动、手动、远程等多种控制模式。应用实践证明,该系统安全可靠、功能完善,可满足不同环境的要求。 展开更多
关键词 自动化 控制 远程 泵房
Assessment of High-standard Farmland Construction Effectiveness in Liaoning Province During 2011–2015 预览
19
作者 PU Luoman ZHANG Shuwen +2 位作者 YANG Jiuchun YAN Fengqin CHANG Liping 《中国地理科学:英文版》 SCIE CSCD 2019年第4期667-678,共12页
At present, the large-scale construction of high-standard farmland in China has improved the quality of cropland and crop production and enhanced the eco-environmental security. To obtain a comprehensive understanding... At present, the large-scale construction of high-standard farmland in China has improved the quality of cropland and crop production and enhanced the eco-environmental security. To obtain a comprehensive understanding of high-standard farmland construction in Liaoning Province of China during the 12 th five-year period(2011–2015), through on-the-spot investigations and remote sensing monitoring, this study assessed the construction effectiveness of ten typical sampling projects in Liaoning Province and then presented practical suggestions. The main conclusions were as follows. 1) The ranges of increase in productivity of the ten sampling projects in Liaoning Province all surpassed the goal of 1500 kg/ha. 2) Among all sampling project areas, the levels of productivity stability of nine sampling projects were higher than that of the surrounding farmland in a severe drought year. However, the productivity stability of the high-standard farmland construction project in Faku County, Yiniupu Town, declined by 1.04% compared with the surrounding farmland. 3) Except for the high-standard farmland construction project in Dengta City, Dengta Irrigation Region, the productivity uniformity of the other nine sampling projects increased by 3.30%–88.10%. 4) Eight of the ten sampling projects belonged to Class 1, and two projects belonged to Class 2, showing that the effectiveness of high-standard farmland construction in Liaoning Province was quite good.There were some suggestions for high-standard farmland construction in the future. All departments should strengthen cooperation and formulate corresponding protection and development strategies suitable for local conditions. Additionally, lasting management mechanisms should also be established. Using remote sensing monitoring to assess the high-standard farmland construction effectiveness during the 12 th five-year period could provide experience and decision-making support for high-standard farmland construction in the future. 展开更多
关键词 high-standard FARMLAND remote sensing monitoring PRODUCTIVITY stability PRODUCTIVITY UNIFORMITY LIAONING Province China
在线阅读 下载PDF
Spatio-temporal Characteristics of Area Coverage and Observation Geometry of the MISR Land-surface BRF Product: A Case Study of the Central Part of Northeast Asia 预览
20
作者 LI Jian CHEN Shengbo +4 位作者 QIN Wenhan Mike MUREFU WANG Yufei YU Yan ZHEN Zhijun 《中国地理科学:英文版》 SCIE CSCD 2019年第4期679-688,共10页
The Multi-angle imaging spectroradiometer(MISR) land-surface(LS) bidirectional reflectance factor(BRF) product(MILS_BRF) has unique semi-simultaneous multi-angle sampling and global coverage. However, unlike on-satell... The Multi-angle imaging spectroradiometer(MISR) land-surface(LS) bidirectional reflectance factor(BRF) product(MILS_BRF) has unique semi-simultaneous multi-angle sampling and global coverage. However, unlike on-satellite observations, the spatio-temporal characteristics of MILS_BRF data have rarely been explicitly and comprehensively analysed. Results from 5-yr(2011–2015) of MILS_BRF dataset from a typical region in central Northeast Asia as the study area showed that the monthly area coverage as well as MILS_BRF data quantity varies significantly, from the highest in October(99.05%) through median in June/July(78.09%/75.21%) to lowest in January(18.97%), and a large data-vacant area exists in the study area during four consecutive winter months(December through March). The data-vacant area is mainly composed of crop lands and cropland/natural vegetation mosaic. The amount of data within the principal plane(PP)±30°(nPP) or cross PP ±30°(nCP), varies intra-annually with significant differences from different view zeniths or forward/backward scattering directions. For example, multiple off-nadir cameras have nPP but no nCP data for up to six months(September through February), with the opposite occurring in June and July. This study provides explicit and comprehensive information about the spatio-temporal characteristics of product coverage and observation geometry of MILS_BRF in the study area. Results provide required user reference information for MILS_BRF to evaluate performance of BRDF models or to compare with other satellite-derived BRF or albedo products. Comparing this final product to on-satellite observations, what was found here reveals a new perspective on product spatial coverage and observation geometry for multi-angle remote sensing. 展开更多
关键词 multi-angle remote sensing Multi-angle Imaging SPECTRORADIOMETER (MISR) bidirectional reflectance factor (BRF) SPATIO-TEMPORAL characteristics OBSERVATION GEOMETRY
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部 意见反馈