Data base systems for remote sensing

1980 ◽  
pp. 299-318 ◽  
Author(s):  
Fred C. Billingsley
Keyword(s):  
Remote Sensing ◽  
Data Base

Methodological approach to creating a catalog of test objects for evaluating the space survey materials quality

2021 ◽  
Vol 976 (10) ◽  
pp. 33-41
Author(s):  
E.V. Bragina
Keyword(s):  
Remote Sensing ◽  
Data Base ◽  
Work Experience ◽  
Information Quality ◽  
Methodological Approach ◽  
A Priori ◽  
Test Site ◽  
The Earth ◽  
Test Objects

The necessity of solving a number of methodological tasks is substantiated, aimed at ensuring the objectivity of estimating the visual, measuring and information quality of materials for remote sensing the Earth on the basis of test sites. The results of generalization of the accumulated practical work experience on creating test sections, which are formalized as a methodological approach to creating a priori data base for assessing the space survey materials quality, are presented. As part of the proposed methodological approach to arranging a priori data base for assessing the Earth remote sensing materials quality, a set of issues related to the requirements for selecting test sites, sampling and justification of test objects at sites, determining the characteristics of these objects, the content of the test site, requirements to the site passport and passports of test objects, to the content of the database in the form of a geoinformation system of the test site is reflected. The urgency of developing a network of test sites for control, calibration and estimating the quality of the obtained materials from space survey systems, the main elements of which are typical objects of natural and anthropogenic origin, is substantiated. A set of issues related to maintaining the test sites up-to-date is considered.

scholarly journals On-line Fault Detection and Diagnosis for Greenhouse Environmental Control

2001 ◽  
Author(s):  
Ido Seginer ◽  
Louis D. Albright ◽  
Robert W. Langhans
Keyword(s):  
Remote Sensing ◽  
Water Stress ◽  
Fault Detection ◽  
Early Detection ◽  
Data Base ◽  
Crop Rotation ◽  
Hyperspectral Remote Sensing ◽  
Sugar Beets ◽  
Detection And Identification ◽  
Wide Range

Background Early detection and identification of faulty greenhouse operation is essential, if losses are to be minimized by taking immediate corrective actions. Automatic detection and identification would also free the greenhouse manager to tend to his other business. Original objectives The general objective was to develop a method, or methods, for the detection, identification and accommodation of faults in the greenhouse. More specific objectives were as follows: 1. Develop accurate systems models, which will enable the detection of small deviations from normal behavior (of sensors, control, structure and crop). 2. Using these models, develop algorithms for an early detection of deviations from the normal. 3. Develop identifying procedures for the most important faults. 4. Develop accommodation procedures while awaiting a repair. The Technion team focused on the shoot environment and the Cornell University team focused on the root environment. Achievements Models: Accurate models were developed for both shoot and root environment in the greenhouse, utilizing neural networks, sometimes combined with robust physical models (hybrid models). Suitable adaptation methods were also successfully developed. The accuracy was sufficient to allow detection of frequently occurring sensor and equipment faults from common measurements. A large data base, covering a wide range of weather conditions, is required for best results. This data base can be created from in-situ routine measurements. Detection and isolation: A robust detection and isolation (formerly referred to as 'identification') method has been developed, which is capable of separating the effect of faults from model inaccuracies and disturbance effects. Sensor and equipment faults: Good detection capabilities have been demonstrated for sensor and equipment failures in both the shoot and root environment. Water stress detection: An excitation method of the shoot environment has been developed, which successfully detected water stress, as soon as the transpiration rate dropped from its normal level. Due to unavailability of suitable monitoring equipment for the root environment, crop faults could not be detected from measurements in the root zone. Dust: The effect of screen clogging by dust has been quantified. Implications Sensor and equipment fault detection and isolation is at a stage where it could be introduced into well equipped and maintained commercial greenhouses on a trial basis. Detection of crop problems requires further work. Dr. Peleg was primarily responsible for developing and implementing the innovative data analysis tools. The cooperation was particularly enhanced by Dr. Peleg's three summer sabbaticals at the ARS, Northem Plains Agricultural Research Laboratory, in Sidney, Montana. Switching from multi-band to hyperspectral remote sensing technology during the last 2 years of the project was advantageous by expanding the scope of detected plant growth attributes e.g. Yield, Leaf Nitrate, Biomass and Sugar Content of sugar beets. However, it disrupted the continuity of the project which was originally planned on a 2 year crop rotation cycle of sugar beets and multiple crops (com and wheat), as commonly planted in eastern Montana. Consequently, at the end of the second year we submitted a continuation BARD proposal which was turned down for funding. This severely hampered our ability to validate our findings as originally planned in a 4-year crop rotation cycle. Thankfully, BARD consented to our request for a one year extension of the project without additional funding. This enabled us to develop most of the methodology for implementing and running the hyperspectral remote sensing system and develop the new analytical tools for solving the non-repeatability problem and analyzing the huge hyperspectral image cube datasets. However, without validation of these tools over a ful14-year crop rotation cycle this project shall remain essentially unfinished. Should the findings of this report prompt the BARD management to encourage us to resubmit our continuation research proposal, we shall be happy to do so.  

scholarly journals A Microphysics Guide to Cirrus – Part II: Climatologies of Clouds and Humidity from Observations

2020 ◽  
Author(s):  
Martina Krämer ◽  
Christian Rolf ◽  
Nicole Spelten ◽  
Armin Afchine ◽  
David Fahey ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Data Base ◽  
Asian Monsoon ◽  
Satellite Observations ◽  
Cirrus Clouds ◽  
The Arctic ◽  
In Situ Data ◽  
Geographical Regions ◽  
The Tropics

Abstract. This study presents airborne in-situ and satellite remote sensing climatologies of cirrus clouds and humidity. The climatologies serve as a guide to the properties of cirrus clouds, with the new in-situ data base providing detailed insights into boreal mid-latitudes and the tropics, while the satellite-borne data set offers a global overview. To this end, an extensive, quality checked data archive, the Cirrus Guide II in-situ data base, is created from airborne in-situ measurements during 150 flights in 24 campaigns. The archive contains meteorological parameters, IWC, Nice, Rice, RHice and H2O for each of the flights (IWC: ice water content, Nice: number concentration of ice crystals, Rice: ice crystal mean mass radius, RHice: relative humidity with respect to ice, H2O: water vapor mixing ratio). Depending on the specific parameter, the data base has extended by about a factor of 5–10 compared to the previous studies of Schiller et al. (2008), JGR, and Krämer et al. (2009), ACP. One result of our investigations is, that across all latitudes, the thicker liquid origin cirrus predominate at lower altitudes, while at higher altitudes the thinner in-situ cirrus prevail. Further, exemplary investigations of the radiative characteristics of in-situ and liquid origin cirrus show that the in-situ origin cirrus only slightly warm the atmosphere, while liquid origin cirrus have a strong cooling effect. An important step in completing the Cirrus Guide II is the provision of the global cirrus Nice climatology, derived by means of the retrieval algorithm DARDAR-Nice from ten years of cirrus remote sensing observations from satellite. The in-situ data base has been used to evaluate and adjust the satellite observations. We found that the global median Nice from satellite observations is almost two times higher than the in-situ median and increases slightly with decreasing temperature. Nice medians of the most frequentl occuring cirrus sorted by geographical regions are highest in the tropics, followed by austral/boreal mid-latitudes, Antarctica and the Arctic. Since the satellite climatologies enclose the entire spatial and temporal Nice occurrence, we could deduce that half of the cirrus are located in the lowest, warmest cirrus layer and contain a significant amount of liquid origin cirrus. A specific highlight of the study is the in-situ observations of tropical tropopause layer (TTL) cirrus and humidity in the Asian monsoon anticyclone and the comparison to the surrounding tropics. In the convectively very active Asian monsoon, peak values of Nice and IWC of 30 ppmv and 1000 ppmv are detected around the cold point tropopause (CPT). Above the CPT, ice particles that are convectively injected can locally add a significant amount of water available for exchange with the stratosphere. We found IWCs of up to 8 ppmv in the Asian monsoon in comparison to only 2 ppmv in the surrounding tropics. Also, the highest RHice inside of the clouds as well as in clear sky (120–150 %) are observed around and above the CPT. We attribute this to the high amount of H2O (3–5 ppmv) in comparison to 1.5–3 ppmv in other tropical regions. The supersaturations above the CPT suggest that the water exchange with the stratosphere is 10–20 % higher than expected in regions of weak convective activity and up to about 50 % in the Asian monsoon.

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