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Air Pollution Risk Assessment Using GIS and Remotely Sensed Data in Kirkuk City,Iraq
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作者 Huda Jamal Jumaah Abed Jasim +1 位作者 Aydin Rashid Qayssar Ajaj 《Journal of Atmospheric Science Research》 2023年第3期41-51,共11页
According to World Health Organization(WHO)estimates and based on a world population review,Iraq ranks tenth among the most air-polluted countries in the world.In this study,the authors tried to evaluate the outdoor a... According to World Health Organization(WHO)estimates and based on a world population review,Iraq ranks tenth among the most air-polluted countries in the world.In this study,the authors tried to evaluate the outdoor air of Kirkuk City north of Iraq.The authors relied on two types of data:field measurements and remotely sensed data.Fifteen air quality points were determined in the study region representing the monthly average measurements im­plemented for the one-year dataset.Geographic information systems(GIS)based geo-statistic and geo-processing techniques have been applied to collected data.Spatial distribution data related to Air Quality Index(AQI),and Par­ticulate Matter(PM10 and PM2.5)were obtained by mapping collected records.Remotely sensed data of PM2.5 were analyzed and compared with the collected data.Health impacts were assessed per each air pollutant determined in the study.Spatial distribution maps revealed the hazardous air type in the study area.Overall AQI ranged between 300 and 472μg/m^(3)referring to unhealthy,very unhealthy,and hazardous classes of pollution.Also,PM10 ranged between 300 and 570μg/m^(3)indicating the same class of air pollution from unhealthy to hazardous.While PM2.5 ranged between 40 and 60μg/m^(3)which represents unhealthy air for sensitive persons and unhealthy air.The remotely sensed data re­vealed different air types for the study period ranging from 14.5 to 52.5μg/m^(3)represented in moderate and unhealthy air for sensitive persons.Significant correlations were obtained where the mean local R2(coefficient of determination)was obtained as 0.83.The assessed data were within high air pollution that requires immediate intervention for con­trolling causes and eliminating their effects. 展开更多
关键词 Air pollution risk AQI GIS Particulate matter Remote sensing
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Calibrating Remotely Sensed Ocean Chlorophyll Data: An Application of the Blending Technique in Three Dimensions (3D) 被引量:1
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作者 Mathias A. Onabid 《Open Journal of Marine Science》 2017年第1期191-204,共14页
In this article, the extension to three dimensions (3D) of the blending technique that has been widely used in two dimensions (2D) to calibrate ocean chlorophyll is presented. The results thus obtained revealed a very... In this article, the extension to three dimensions (3D) of the blending technique that has been widely used in two dimensions (2D) to calibrate ocean chlorophyll is presented. The results thus obtained revealed a very high degree of efficiency when predicting observed values of ocean chlorophyll. The mean squared difference between the predicted and observed values of ocean chlorophyll when 3D technique was used fell far below the tolerance level which was set to the difference between satellite and observed in-situ values. The resulting blended field did not only provide better predictions of the in situ observations in areas where bottle samples cannot be obtained but also provided a smooth variation of the distribution of ocean chlorophyll throughout the year. An added advantage is its computational efficiency since data that would have been treated at least four times would be treated only once. With the advent of these results, it is believed that the modelling of the ocean life cycle will become more realistic. 展开更多
关键词 IN-SITU 3D-Blending SATELLITE Over-Relaxation Method Calibration remotely Sensed Data
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Remotely Activated Nanoparticles for Anticancer Therapy
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作者 Luisa Racca Valentina Cauda 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第1期174-207,共34页
Cancer has nowadays become one of the leading causes of death worldwide.Conventional anticancer approaches are associated with different limitations.Therefore,innovative methodologies are being investigated,and severa... Cancer has nowadays become one of the leading causes of death worldwide.Conventional anticancer approaches are associated with different limitations.Therefore,innovative methodologies are being investigated,and several researchers propose the use of remotely activated nanoparticles to trigger cancer cell death.The idea is to conjugate two different components,i.e.,an external physical input and nanoparticles.Both are given in a harmless dose that once combined together act synergistically to therapeutically treat the cell or tissue of interest,thus also limiting the negative outcomes for the surrounding tissues.Tuning both the properties of the nanomaterial and the involved triggering stimulus,it is possible furthermore to achieve not only a therapeutic effect,but also a powerful platform for imaging at the same time,obtaining a nano-theranostic application.In the present review,we highlight the role of nanoparticles as therapeutic or theranostic tools,thus excluding the cases where a molecular drug is activated.We thus present many examples where the highly cytotoxic power only derives from the active interaction between different physical inputs and nanoparticles.We perform a special focus on mechanical waves responding nanoparticles,in which remotely activated nanoparticles directly become therapeutic agents without the need of the administration of chemotherapeutics or sonosensitizing drugs. 展开更多
关键词 Anticancer therapy remotely activated nanomedicine Stimuli-responsive nanoparticles Physical stimulation RADIOFREQUENCY Nanoparticle-assisted ultrasound HYPERTHERMIA
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Using Boosted Regression Trees and Remotely Sensed Data to Drive Decision-Making
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作者 Brigitte Colin Samuel Clifford +2 位作者 Paul Wu Samuel Rathmanner Kerrie Mengersen 《Open Journal of Statistics》 2017年第5期859-875,共17页
Challenges in Big Data analysis arise due to the way the data are recorded, maintained, processed and stored. We demonstrate that a hierarchical, multivariate, statistical machine learning algorithm, namely Boosted Re... Challenges in Big Data analysis arise due to the way the data are recorded, maintained, processed and stored. We demonstrate that a hierarchical, multivariate, statistical machine learning algorithm, namely Boosted Regression Tree (BRT) can address Big Data challenges to drive decision making. The challenge of this study is lack of interoperability since the data, a collection of GIS shapefiles, remotely sensed imagery, and aggregated and interpolated spatio-temporal information, are stored in monolithic hardware components. For the modelling process, it was necessary to create one common input file. By merging the data sources together, a structured but noisy input file, showing inconsistencies and redundancies, was created. Here, it is shown that BRT can process different data granularities, heterogeneous data and missingness. In particular, BRT has the advantage of dealing with missing data by default by allowing a split on whether or not a value is missing as well as what the value is. Most importantly, the BRT offers a wide range of possibilities regarding the interpretation of results and variable selection is automatically performed by considering how frequently a variable is used to define a split in the tree. A comparison with two similar regression models (Random Forests and Least Absolute Shrinkage and Selection Operator, LASSO) shows that BRT outperforms these in this instance. BRT can also be a starting point for sophisticated hierarchical modelling in real world scenarios. For example, a single or ensemble approach of BRT could be tested with existing models in order to improve results for a wide range of data-driven decisions and applications. 展开更多
关键词 Boosted Regression Trees remotely Sensed DATA BIG DATA MODELLING Approach MISSING DATA
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A STUDY OF SOIL CONSERVATION MONITORING INFORMATION SYSTEM BASED ON REMOTELY SENSED DATA FOR A CATCHMENT ON THE LOESS PLATEAU
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作者 Li Rui, Li Bichen, Ma Xiaoyun (Northwesterng Institute of Soil and Water Conservation, Academia Sinica and Ministry of Water Resources) 《遥感信息》 CSCD 1990年第A02期41-42,共2页
The Soil Conservation Monitorins Information System (SCMIS) presented in this paper is oriented to soil erosion control, resources exploitation, utilization, planning and management for a small watershed (about 10 sq.... The Soil Conservation Monitorins Information System (SCMIS) presented in this paper is oriented to soil erosion control, resources exploitation, utilization, planning and management for a small watershed (about 10 sq. km.) on the Loess Plateau. It sums up Remote sensing (RS), Geographical Information System (GIS) and Expert System (ES) and consists of a integrated system. As a basic level information system of Loess Plateau, its perfection and psreading will bring about a great advance in resources exploitation and management of Loess Plateau. 展开更多
关键词 SCMIS A STUDY OF SOIL CONSERVATION MONITORING INFORMATION SYSTEM BASED ON remotely SENSED DATA FOR A CATCHMENT ON THE LOESS PLATEAU GIS data
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远程控制IE也在行——Remotely Anywhere
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作者 Smart Net 《电脑》 2004年第6期138-139,共2页
关键词 远程控制 remotely Anywhere软件 WAP手机 PDA 激活 定制 HTTP协议 性能监视
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Assessment of Urban Heat Island Using Remotely Sensed Imagery over Greater Cairo, Egypt 被引量:8
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作者 Khaled Abutaleb Adeline Ngie +3 位作者 Ahmed Darwish Mahmoud Ahmed Sayed Arafat Fathi Ahmed 《Advances in Remote Sensing》 2015年第1期35-47,共13页
The Urban Heat Island (UHI) results in significant and sometimes dramatic increases in air temperature differences between the urban environment and its surrounding areas. The heat island structure may extend from the... The Urban Heat Island (UHI) results in significant and sometimes dramatic increases in air temperature differences between the urban environment and its surrounding areas. The heat island structure may extend from the ground to the top of roofs and canopy levels above ground. The Urban Heat Island effect is a leading factor in a long list of human health problems which are expected to increase with the rapid growth of urban populations and projected future climate change. Urban heat island studies can be conducted through either direct measurements of air temperature using automobile transects and weather station networks or through measuring surface temperature using airborne or satellite remote sensing. In this study, UHI was investigated over the Greater Cairo during both summer and winter seasons over two different dates. Landsat 7 ETM+ data were used and the mono-window algorithm was applied in the study. Results emphasis that both types of heat islands exist in the study area i.e. the surface and the atmospheric heat islands. Temperature differences ranged between 0.5°C to 3.5°C and these are much related to the existing land use/covers. It could be concluded that expansion of urban areas in Greater Cairo has led to increased thermal radiation of land surface on the highly populated areas. 展开更多
关键词 UHI Landsat Remote Sensing Mono-Window GREATER CAIRO
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A Review on Extraction of Lakes from Remotely Sensed Optical Satellite Data with a Special Focus on Cryospheric Lakes 被引量:4
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作者 Shridhar D. Jawak Kamana Kulkarni Alvarinho J. Luis 《Advances in Remote Sensing》 2015年第3期196-213,共18页
Water on the Earth’s surface is an essential part of the hydrological cycle. Water resources include surface waters, groundwater, lakes, inland waters, rivers, coastal waters, and aquifers. Monitoring lake dynamics i... Water on the Earth’s surface is an essential part of the hydrological cycle. Water resources include surface waters, groundwater, lakes, inland waters, rivers, coastal waters, and aquifers. Monitoring lake dynamics is critical to favor sustainable management of water resources on Earth. In cryosphere, lake ice cover is a robust indicator of local climate variability and change. Therefore, it is necessary to review recent methods, technologies, and satellite sensors employed for the extraction of lakes from satellite imagery. The present review focuses on the comprehensive evaluation of existing methods for extraction of lake or water body features from remotely sensed optical data. We summarize pixel-based, object-based, hybrid, spectral index based, target and spectral matching methods employed in extracting lake features in urban and cryospheric environments. To our knowledge, almost all of the published research studies on the extraction of surface lakes in cryospheric environments have essentially used satellite remote sensing data and geospatial methods. Satellite sensors of varying spatial, temporal and spectral resolutions have been used to extract and analyze the information regarding surface water. Multispectral remote sensing has been widely utilized in cryospheric studies and has employed a variety of electro-optical satellite sensor systems for characterization and extraction of various cryospheric features, such as glaciers, sea ice, lakes and rivers, the extent of snow and ice, and icebergs. It is apparent that the most common methods for extracting water bodies use single band-based threshold methods, spectral index ratio (SIR)-based multiband methods, image segmentation methods, spectral-matching methods, and target detection methods (unsupervised, supervised and hybrid). A Synergetic fusion of various remote sensing methods is also proposed to improve water information extraction accuracies. The methods developed so far are not generic rather they are specific to either the location or satellite imagery or to the type of the feature to be extracted. Lots of factors are responsible for leading to inaccurate results of lake-feature extraction in cryospheric regions, e.g. the mountain shadow which also appears as a dark pixel is often misclassified as an open lake. The methods which are working well in the cryospheric environment for feature extraction or landcover classification does not really guarantee that they will be working in the same manner for the urban environment. Thus, in coming years, it is expected that much of the work will be done on object-based approach or hybrid approach involving both pixel as well as object-based technology. A more accurate, versatile and robust method is necessary to be developed that would work independent of geographical location (for both urban and cryosphere) and type of optical sensor. 展开更多
关键词 Cryospehere REMOTE Sensing SEMI-AUTOMATIC EXTRACTION LAKES SPECTRAL Index Ratio
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Quantification of Sand Dune Movements in the South Western Part of Egypt, Using Remotely Sensed Data and GIS 被引量:3
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作者 Islam Abou El-Magd Osman Hassan Sayed Arafat 《Journal of Geographic Information System》 2013年第5期498-508,共11页
Sand dune movement is a hazardous phenomenon in Egypt and creates major threat on the existing land use and land cover as well as developmental plans. This paper studied the sand dune morphology and quantified the rat... Sand dune movement is a hazardous phenomenon in Egypt and creates major threat on the existing land use and land cover as well as developmental plans. This paper studied the sand dune morphology and quantified the rate of sand dune movements and direction in a newly developed project in the southwest of Egypt. Two dates of satellite imageries were used to trace the Barchan dunes at various sites with different morphological properties to estimate the annual movement rate based on point to point geo-correlations. 149 dunes of the common sand dunes in the area of study including barchans and transverse dunes were studied to accurately determine their rate of movements, which ranged from 1.3 to 19.3 my-1. The direction of sand dune movements was mainly to the south and slightly southeast with range from 265 to 295 degrees. The quantification of sand dune movement and direction has, indeed, enabled to determine the major threat on the exiting land use and land cover as well as the newly developmental projects. 展开更多
关键词 SAND DUNE Natural Hazards REMOTE Sensing GIS EGYPT
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Coupling numerical simulation with remotely sensed information for the study of frozen soil dynamics 被引量:2
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作者 HuiRan Gao WanChang Zhang 《Research in Cold and Arid Regions》 CSCD 2020年第6期404-417,共14页
The acquisition of spatial-temporal information of frozen soil is fundamental for the study of frozen soil dynamics and its feedback to climate change in cold regions.With advancement of remote sensing and better unde... The acquisition of spatial-temporal information of frozen soil is fundamental for the study of frozen soil dynamics and its feedback to climate change in cold regions.With advancement of remote sensing and better understanding of frozen soil dynamics,discrimination of freeze and thaw status of surface soil based on passive microwave remote sensing and numerical simulation of frozen soil processes under water and heat transfer principles provides valuable means for regional and global frozen soil dynamic monitoring and systematic spatial-temporal responses to global change.However,as an important data source of frozen soil processes,remotely sensed information has not yet been fully utilized in the numerical simulation of frozen soil processes.Although great progress has been made in remote sensing and frozen soil physics,yet few frozen soil research has been done on the application of remotely sensed information in association with the numerical model for frozen soil process studies.In the present study,a distributed numerical model for frozen soil dynamic studies based on coupled water-heat transferring theory in association with remotely sensed frozen soil datasets was developed.In order to reduce the uncertainty of the simulation,the remotely sensed frozen soil information was used to monitor and modify relevant parameters in the process of model simulation.The remotely sensed information and numerically simulated spatial-temporal frozen soil processes were validated by in-situ field observations in cold regions near the town of Naqu on the East-Central Tibetan Plateau.The results suggest that the overall accuracy of the algorithm for discriminating freeze and thaw status of surface soil based on passive microwave remote sensing was more than 95%.These results provided an accurate initial freeze and thaw status of surface soil for coupling and calibrating the numerical model of this study.The numerically simulated frozen soil processes demonstrated good performance of the distributed numerical model based on the coupled water-heat transferring theory.The relatively larger uncertainties of the numerical model were found in alternating periods between freezing and thawing of surface soil.The average accuracy increased by about 5%after integrating remotely sensed information on the surface soil.The simulation accuracy was significantly improved,especially in transition periods between freezing and thawing of the surface soil. 展开更多
关键词 frozen soil water-heat coupled model passive microwave remote sensing COUPLING frozen soil dynamics
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Spatial Pattern of Land Cover Change Using Remotely Sensed Imagery and GIS: A Case Study of Omo-Shasha-Oluwa Forest Reserve, SW Nigeria (1986-2002) 被引量:1
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作者 Oludare H. Adedeji Clement O. Adeofun 《Journal of Geographic Information System》 2014年第4期375-385,共11页
Spatial patterns of land cover changes in the Omo-Shasha-Oluwa Forest Reserves were conducted on Landsat TM and ETM+ imageries of 1986 and 2002 using remote sensing and GIS techniques. Extent of tree plantation (Gmeli... Spatial patterns of land cover changes in the Omo-Shasha-Oluwa Forest Reserves were conducted on Landsat TM and ETM+ imageries of 1986 and 2002 using remote sensing and GIS techniques. Extent of tree plantation (Gmelina arborea) grew from about 145 sq. km in 1986 to about 322 sq. km in 2002 (122% increase). The natural forest declined from about 2569 sq. km in 1986 to about 2253 sq. km by 2002, while the non-forest areas increased by some 5% from 341 km2?in 1986 to about 490 km2?by 2002. Land cover pattern and its changes in the study area are linked to both natural and anthropogenic processes such as illegal logging, demand for soft wood for industries and expansion of settlements. The conversion of natural forest into monoculture plantations should be discouraged because they do not give room for biodiversity. Specific forestry and environmental laws and regulations that significantly address landscape changes in reserved and protected areas should be enforced to reduce activities that negatively affect the forest reserves. There is also the need to develop a wider and more integrated GIS system of the forest and other land resources in the country to assist different kinds of planning and management activities. 展开更多
关键词 Classification Land COVER CHANGE Change-Detection GIS Landsat TM and ETM+ Remote Sensing Omo-Shasha-Oluwa Forest RESERVE
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Remotely sensed estimation and mapping of soil moisture by eliminating the effect of vegetation cover
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作者 WU Cheng-yong CAO Guang-chao +6 位作者 CHEN Ke-long E Chong-yi MAO Ya-hui ZHAO Shuangkai WANG Qi SU Xiao-yi WEI Ya-lan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第2期316-327,共12页
Soil moisture(SM), which plays a crucial role in studies of the climate, ecology, agriculture and the environment, can be estimated and mapped by remote sensing technology over a wide region. However, remotely sensed ... Soil moisture(SM), which plays a crucial role in studies of the climate, ecology, agriculture and the environment, can be estimated and mapped by remote sensing technology over a wide region. However, remotely sensed SM is constrained by its estimation accuracy, which mainly stems from the influence of vegetation cover on soil spectra information in mixed pixels. To overcome the low-accuracy defects of existing surface albedo method for estimating SM, in this paper, Qinghai Lake Basin, an important animal husbandry production area in Qinghai Province, China, was chosen as an empirical research area. Using the surface albedo computed from moderate resolution imaging spectroradiometer(MODIS) reflectance products and the actual measured SM data, an albedo/vegetation coverage trapezoid feature space was constructed. Bare soil albedo was extracted from the surface albedo mainly containing information of soil, vegetation, and both albedo models for estimating SM were constructed separately. The accuracy of the bare soil albedo model(root mean square error=4.20, mean absolute percent error=22.75%, and theil inequality coefficient=0.67) was higher than that of the existing surface albedo model(root mean square error=4.66, mean absolute percent error=25.46% and theil inequality coefficient=0.74). This result indicated that the bare soil albedo greatly improved the accuracy of SM estimation and mapping. As this method eliminated the effect of vegetation cover and restored the inherent soil spectra, it not only quantitatively estimates and maps SM at regional scales with high accuracy, but also provides a new way of improving the accuracy of soil organic matter estimation and mapping. 展开更多
关键词 SOIL moisture remote sensing BARE SOIL ALBEDO TRAPEZOID feature space QINGHAI Lake Basin
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Detecting remotely triggered temporal changes around the Parkfield section of the San Andreas fault
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作者 Peng Zhao Zhigang Peng Karim Ghazi Sabra 《Earthquake Science》 CSCD 2010年第5期497-509,共13页
Detecting temporal changes in fault zone properties at seismogenic depth have been a long-sought goal in the seismological community for many decades.Recent studies based on waveform analysis of repeating earthquakes ... Detecting temporal changes in fault zone properties at seismogenic depth have been a long-sought goal in the seismological community for many decades.Recent studies based on waveform analysis of repeating earthquakes have found clear temporal changes in the shallow crust and around active fault zones associated with the occurrences of large nearby and teleseismic earthquakes.However,repeating earthquakes only occur in certain locations and their occurrence times cannot be controlled,which may result in inadequate sampling of the interested regions or time periods.Recent developments in passive imaging via auto-and cross-correlation of ambient seismic wavefields (e.g.,seismic noise,earthquake coda waves) provide an ideal source for continuous monitoring of temporal changes around active fault zones.Here we conduct a systematic search of temporal changes along the Parkfield section of the San Andreas fault by cross-correlating relatively high-frequency (0.4-1.3 Hz) ambient noise signals recorded by 10 borehole stations in the High Resolution Seismic Network.After using stretch/compressed method to measure the delay time and the decorrelation-index between the daily noise cross-correlation functions (NCCFs),we find clear temporal changes in the median seismic velocity and decorrelation-index associated with the 2004 M6.0 Parkfield earthquake.We also apply the same procedure to the seismic data around five regional/teleseismic events that have triggered non-volcanic tremor in the same region,but failed to find any clear temporal changes in the daily NCCFs.The fact that our current technique can detect temporal changes from the nearby but not regional and teleseismic events,suggests that temporal changes associated with distance sources are very subtle or localized so that they could not be detected within the resolution of the current technique (~0.2%). 展开更多
关键词 temporal changes remote triggering seismic noise CROSS-CORRELATION INTERFEROMETRY seismic coda
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A 2D GIS Approach for Mapping Aquiferous Zones Using Remotely Sensed Data within Obubra, Southeast-Nigeria
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作者 Ebenezer A. Kudamnya Ruth O. Sylvanus +2 位作者 Mary T. Essien Adamu A. Vulegbo Benjamin O. Omang 《Journal of Water Resource and Protection》 2019年第6期758-776,共19页
Groundwater is vital to the sustenance and well-being of man-kind, although it is constantly under immense pressure. For this reason, there is need to develop an effective, reliable, scientific and sustainable means o... Groundwater is vital to the sustenance and well-being of man-kind, although it is constantly under immense pressure. For this reason, there is need to develop an effective, reliable, scientific and sustainable means of delineating zones of groundwater occurrence and distribution with high precision in other to effectively explore for this resource. In this study, remote sensing (RS) and geographical information system (GIS) have been combined to develop thematic maps of the zones of groundwater occurrence and distribution based on variable factors such as;elevation, drainage, lineament, slope, lithology and soil. The analytical hierarchy procedure (AHP) was employed to classify and subsequently assign weight to each variable factor through weighted overlay analysis. Integration of these factors with their relative classes defined was used to produce a 2D-model for predicting surface aquifers mapped within Obubra. The study delineated three (3) surface aquifer zones representing groundwater potential zones. Zones representing high groundwater potential cover an area of approximately 331.94 Km2, accounting for 29.58% of the study area. The region that represents moderate to good groundwater occurrence and distribution covers an estimated area of approximately 648.42 Km2, occupying 57.78% of the study area. Zones with groundwater of low potential account for a total surface area of approximately 141.81 Km2 which is about 12.64% of the entire study area. Regions that show good to moderate and high groundwater potentials, have a wider distribution all across the study area except at the southernmost part. The study therefore shows that it is effective in delineating surface potential zones and hitherto a 2D surface aquifer model for groundwater exploration campaigns within Obubra and its environs. 展开更多
关键词 GROUNDWATER AQUIFER Mapping AHP REMOTE Sensing ZONES
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Soil Moisture Retrieval Quantitatively with Remotely Sensed Data and Its Crucial Factors Analysis
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作者 Ji JIAN Peifen PAN +1 位作者 Yuanyuan CHEN Wunian YANG 《Journal of Water Resource and Protection》 2009年第6期439-447,共9页
The Ts/NDVI method was adopted to retrieve soil moisture with multi-temporal and multi-sensor remotely sensed data f ETM+ and ASTER in study area. The retrieved soil moisture maps were consistent with the soil type an... The Ts/NDVI method was adopted to retrieve soil moisture with multi-temporal and multi-sensor remotely sensed data f ETM+ and ASTER in study area. The retrieved soil moisture maps were consistent with the soil type and vegetation, which were also the two main factors determining the distribution of soil moisture. 展开更多
关键词 Soil MOISTURE QUANTITATIVE REMOTE Sensing NDVI
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Riverine Flood Damage Assessment of Cultivated Lands along Chenab River Using GIS and Remotely Sensed Data: A Case Study of District Hafizabad, Punjab, Pakistan
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作者 Khurram Chohan Sajid Rashid Ahmad +1 位作者 Zia ul Islam Muhammad Adrees 《Journal of Geographic Information System》 2015年第5期506-526,共21页
Flood is one of a kind of disasters which harms human and animal life around the globe. Pakistan has been observing massive floods for many years because of daily and seasonal variation in the temperature levels. Whea... Flood is one of a kind of disasters which harms human and animal life around the globe. Pakistan has been observing massive floods for many years because of daily and seasonal variation in the temperature levels. Wheat, rice, sugarcane and cotton are major crops cultivated in Punjab region of Pakistan in which rice and sugarcane are mostly effected by floods. In this research paper, damage assessment of cultivated land in district Hafizabad along Chenab River has been calculated. Supervised Classification and Soil Adjusted Vegetation Index (SAVI) methods are applied. Pre-flood 2014, post-flood 2014, and pre-flood 2015 Landsat 8 images have been used to calculate the extent of damages to cultivated lands. Water, sand, silt, bare soil and vegetation are classified to identify damage. Results show that vegetation cover has plummeted to 50% after the arrival of flood 2014 in the Chenab. Similarly, 6.7047% of sand and 15.7339% of bare soil deposits have surfaced which have not yet been removed from fertile lands in 2015. 18.4376% standing crop damage has been analyzed under this study. 14.0245% silt deposits have been calculated as post-flood effects. 46.4260% land has been cultivated in 2015 which is 15.5024% lower than 2014 cultivated land. Furthermore, field verification survey has given promising results and has a great correlation with satellite based recovery results. 展开更多
关键词 FLOOD SAVI Supervised Classification GIS Remote Sensing Damage ASSESSMENT Sand
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Simplistic Universal Protocols for Remotely Preparing Arbitrary Equatorial States
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作者 MA Song-ya LI Xiang LI Qi 《Chinese Quarterly Journal of Mathematics》 2022年第3期260-273,共14页
We first put forward a deterministic protocol to realize the remote preparation of arbitrary multi-qubit equatorial states via EPR pairs.A set of useful measurement basis is constructed which plays a key role.The rece... We first put forward a deterministic protocol to realize the remote preparation of arbitrary multi-qubit equatorial states via EPR pairs.A set of useful measurement basis is constructed which plays a key role.The receiver just needs to perform Pauli Z operations to recover the target state.Comparing with the previous protocols,the recovery operation is simplified and expressed by a general formula.As there are no universal protocols for high-dimensional systems,we further generalize to the case of multi-qudit equatorial states by means of Fourier transformation.It is worth mentioning that the proposed schemes can be extended to multi-party controlled remote state preparation.Moreover,we consider the effect of two-type decoherence noises. 展开更多
关键词 Remote state preparation Multi-qudit equatorial state Fourier transformation Recovery operation State-independent average fidelity
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Using GIS for Time Series Analysis of the Dead Sea from Remotely Sensing Data
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作者 Maher A. El-Hallaq Mohammed O. Habboub 《Open Journal of Civil Engineering》 2014年第4期386-396,共11页
Developed tools of Remote Sensing and Geographic Information System are rapidly spread in recent years in order to manage natural resources and to monitor environmental changes. This research aims to study the spatial... Developed tools of Remote Sensing and Geographic Information System are rapidly spread in recent years in order to manage natural resources and to monitor environmental changes. This research aims to study the spatial behavior of the Dead Sea through time. To achieve this aim, time series analysis has been performed to track this behavior. For this purpose, fifteen satellite imageries are collected from 1972 to 2013 in addition to 2011-ASTGTM-DEM. Then, the satellite imageries are radiometrically and atmospherically corrected. Geographic Information system and Remote Sensing techniques are used for the spatio-temporal analysis in order to detect changes in the Dead Sea area, shape, water level, and volume. The study shows that the Dead Sea shrinks by 2.9 km2/year while the water level decreases by 0.65 m/year. Consequently, the volume changes by –0.42 km3/year. The study has also concluded that the direction of this shrinkage is from the north, northwest and from the south direction of the northern part due to the nature of the bathymetric slopes. In contrast, no shrinkage is detected from the east direction due to the same reason since the bathymetric slope is so sharp. The use of the Dead Sea water for industrial purposes by both Israel and Jordan is one of the essential factors that affect the area of the Dead Sea. The intensive human water consumption from the Jordan and Yarmouk Rivers for other usages is another main reason of this shrinkage in the area as well. 展开更多
关键词 DEAD SEA TIME Series Analysis REMOTE SENSING GIS
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Remotely Controlled Automated Horse Jump
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作者 Ibrahim Al-Bahadly Joel White 《Circuits and Systems》 2011年第1期25-33,共9页
With the application of automation, a horse jump can be controlled with the push of a button, or even a remote control. This enables the rider to adjust the jump to suit their needs while still on their horse. The obj... With the application of automation, a horse jump can be controlled with the push of a button, or even a remote control. This enables the rider to adjust the jump to suit their needs while still on their horse. The objective of this work is to design and build a wireless remote motor controller which will be applied to a prototype horse jump. The user will be able to control the forward and reverse direction of the motor by pushing a button or switch via RF remote control. A horse jump prototype consisting of a single jump stand will be constructed. 展开更多
关键词 AUTOMATION HORSE JUMP Dc MOTOR RF REMOTE Control
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Analysis of Mountain Rangeland Changes, Using Remotely-Sensed Data, (Case Study: Dehdez Area, Iran)
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作者 Ali A. Torahi Elham Manuchehri 《Journal of Geoscience and Environment Protection》 2016年第1期100-106,共7页
The land-cover dynamics has been quite conspicuous over the last three decades in Dehdez area, Iran. Therefore, the present study was undertaken in the Dehdez area to assess the trends of rangelands dynamics in the st... The land-cover dynamics has been quite conspicuous over the last three decades in Dehdez area, Iran. Therefore, the present study was undertaken in the Dehdez area to assess the trends of rangelands dynamics in the study area during the period 1990-2006. Two clear, cloud-free Landsat and one ASTER images were selected to classify the study area. All images were rectified to UTM zone 39, WGS84 using at least 25 well distributed ground control points and nearest neighbor resampling. Land-use/cover mapping is achieved through interpretation of Landsat TM satellite images of 1990, 1998 and ASTER image of 2006. Fieldwork was carried out to collect data for training and validating land-use/cover interpretation from satellite image of 2006, and for qualitative description of the characteristics of each land-use/cover class. In order to create a testing sample set, first of all, a set of testing points was selected randomly. A supervised classification technique with Maximum Likelihood Algorithm was applied based on 48 training samples for the image of 2006, and 42 samples for the images of 1990 and 1998 and the land-use/cover maps were produced. Error matrices were used to assess classification accuracy. The results showed rangeland covers about 30.8%, 36.7% and 45% of the total geographical area of the Dehdez area in 1990, 1998 and 2006, respectively. Overall accuracies of land-use/cover classification for 1990, 1998 and 2006 were 89.37%, 75.24% and 71.14%, respectively. Kappa values obtained were of 78.71%, 55.61% and 51.41% of accuracy for the 1990, 1998 and 2006, respectively. During 16 years span period (1990-2006) about 1738.4 ha, 383.7 ha, 32.8 ha and 890.1 ha of rangelands were converted to forest, agriculture, water and settlement. The total rich rangelands in the area, accounted for 38.5%, 44% and 42.2% in 1990, 1998 and 2006, respectively. The total poor rangeland in the area accounted for 61.5%, 56% and 57.8% in 1990, 1998 and 2006, respectively. Satellite Remote Sensing enabled the generation of a detailed rangeland map and the separation of grazing intensity levels in rangelands could be generated with the relatively little effort in areas that were difficult to access. 展开更多
关键词 RANGELAND CHANGES Remote Sensing Dehdez Iran
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