1,894 research outputs found
The Use of Principal Components for Creating Improved Imagery for Geometric Control Point Selection
A directed principal component (PC) analysis and its transformation was applied to 7-channel thematic mapper simulator (TMS) data and 4-channel LANDSAT multispectral scanner system (MSS) data collected over the city of Lancaster, Pennsylvania, to create improved imagery for geometric control point selection for image to image registration. Nineteen temporally stable geometric control points, such as road interactions and bridges, were selected for a 236 sq km area. The control points were visible on both the TMS and MSS imagery. On the first attempt the corresponding image control points were selected on both data sets without using the principal components transformation. Many of the road intersection locations were visible but the actual road crossings could not be distinguished. As a result, mensuration errors using raw data exceeded the equivalent of two (79 x 79 m) pixels. The application of a guided principal components transformation yielded TMS and MSS single band images showing improved detail in the scene's urban and residential infrastructure. The PC transformed data sets were then utilized for the reselection of geometric control points. By shown greater detail, control points on both the TMS and MSS imagery could be located with greater precision using the PC transformed data
The ultraviolet variability of the T Tauri star RW Aurigae
Between 1978 and 1979 the visible brightness of RW Aurigae increased by 0.9 mag. During this time (1) CIV and SiIV increased by factors of 2 to 4 while the lower ionization lines remained unchanged; (2) the fluorescent OI line increased by a factor of 8; (3) the shell spectrum changed from emission to absorption; and (4) the ultraviolet continuum brightened by 2.3 mag. On a time scale of a week the continuum varied by as much as 0.8 mag., but the MgII emission lines showed no variability over 10 percent. An active chromosphere, transition region, and envelope cooled by mass loss are hypothesized in order to explain the ultraviolet observations of RW Aur
Principal Components as a Data Reduction and Noise Reduction Technique
The potential of principal components as a pipeline data reduction technique for thematic mapper data was assessed and principal components analysis and its transformation as a noise reduction technique was examined. Two primary factors were considered: (1) how might data reduction and noise reduction using the principal components transformation affect the extraction of accurate spectral classifications; and (2) what are the real savings in terms of computer processing and storage costs of using reduced data over the full 7-band TM complement. An area in central Pennsylvania was chosen for a study area. The image data for the project were collected using the Earth Resources Laboratory's thematic mapper simulator (TMS) instrument
Thiorhodococcus mannitoliphagus sp. nov., a new purple sulfur bacterium from the White Sea
A novel purple sulfur bacterium, strain WS(T), was isolated from a microbial mat from an estuary of the White Sea. Individual cells are coccoid shaped, motile by flagella and do not contain gas vesicles. The mean cell diameter is 1.85 mum (range 1.5-2.0 mum). Cell suspensions exhibit a purple-violet colour. They contain bacteriochlorophyll a and carotenoids of the rhodopinal series as photosynthetic pigments. The novel bacterium is an anoxygenic photoautotroph, using sulfide, thiosulfate, sulfite and elemental sulfur as electron donors for photosynthesis and is capable of photoassimilating several organic carbon sources in the presence of carbonate and a reduced sulfur source (sulfide and/or thiosulfate). Sulfur globules, formed during oxidation of sulfide, are stored transiently inside the cells. Optimal salinity and pH for growth are at 0.5-2.0 % NaCl and pH 7.0-7.5. The DNA base composition of strain WS(T) is 61.8 mol% G+C. 16S rRNA gene sequence analysis showed that the new isolate belongs to the genus Thiorhodococcus, with Thiorhodococcus minor CE2203(T) as the nearest relative (sequence similarity of 97.3 %). Several distinct differences from described species necessitate the description of a novel species. Thiorhodococcus mannitoliphagus sp. nov. is the proposed name, with strain WS(T) (=ATCC BAA-1228(T)=VKM B-2393(T)) as the type strain
International Committee on Systematics of Prokaryotes. Subcommittee on the taxonomy of phototrophic bacteria. Minutes of the meetings 2000, Barcelona, Spain
Integrating Grazing with 2,4-D and Florpyrauxifen to Control Broadleaf Weeds and Maintain Red Clover Productivity in Grass-Legume Pastures
In grass-legume pastures, 2,4-D-amine + florpyrauxifen-benzyl controls broadleaf weeds but red clover (Trifolium pratense L.) is eliminated. Grazing within a week prior to herbicide application is likely to reduce leaf surface area and may reduce red clover injury and maintain productivity. Experiments were conducted in 2020 and in 2021 to determine if red clover could be productive when 560 g ae ha-1 2,4-D-amine + 6.3 g ae ha-1 of florpyrauxifen-benzyl with 1% v/v methylated seed oil applied in the spring was grazed before or after herbicide application. Grazing timings occurred 6, 4, or 2 days prior to herbicide application, the day of application, or 6 days after application. Grazing timing did not affect productivity or cover of red clover, white clover, forage grasses, broadleaf weeds, or annual grasses. In contrast, aboveground biomass of broadleaf weeds, red clover, and white clover was \u3e 55, 56, and 44% less, respectively, in 2,4-D-amine + florpyrauxifenbenzyl treated pasture than nontreated pasture. Less clover and broadleaf weed biomass in herbicide treated pasture was associated with 16% more perennial grass biomass and no changes in total forage productivity. Results suggest that all grazing timings applied with 2,4-D-amine + florpyrauxifen-benzyl provided effective weed control that persisted more than 1 year with only partial injury to red clover populations. Grazing in concert with herbicide applications improves herbicide selectivity of preferentially grazed species, while improved from conventional standards practicality to producers is still unknown
Analysis of High Dimensional Data from Intensive Care Medicine
As high dimensional data occur as a rule rather than an exception in critical care today, it is of utmost importance to improve acquisition, storage, modelling, and analysis of medical data, which appears feasable only with the help of bedside computers. The use of clinical information systems offers new perspectives of data recording and also causes a new challenge for statistical methodology. A graphical approach for analysing patterns in statistical time series from online monitoring systems in intensive care is proposed here as an example of a simple univariate method, which contains the possibility of a multivariate extension and which can be combined with procedures for dimension reduction
Integrating Grazing with 2,4-D and Florpyrauxifen to Control Broadleaf Weeds and Maintain Red Clover Productivity in Grass-Legume Pastures
In grass-legume pastures, 2,4-D-amine + florpyrauxifen-benzyl controls broadleaf weeds but red clover (Trifolium pratense L.) is eliminated. Grazing within a week prior to herbicide application is likely to reduce leaf surface area and may reduce red clover injury and maintain productivity. Experiments were conducted in 2020 and in 2021 to determine if red clover could be productive when 560 g ae ha-1 2,4-D-amine + 6.3 g ae ha-1 of florpyrauxifen-benzyl with 1% v/v methylated seed oil applied in the spring was grazed before or after herbicide application. Grazing timings occurred 6, 4, or 2 days prior to herbicide application, the day of application, or 6 days after application. Grazing timing did not affect productivity or cover of red clover, white clover, forage grasses, broadleaf weeds, or annual grasses. In contrast, aboveground biomass of broadleaf weeds, red clover, and white clover was \u3e55, 56, and 44% less, respectively, in 2,4-D-amine + florpyrauxifenbenzyl treated pasture than nontreated pasture. Less clover and broadleaf weed biomass in herbicide treated pasture was associated with 16% more perennial grass biomass and no changes in total forage productivity. Results suggest that all grazing timings applied with 2,4-D-amine + florpyrauxifen-benzyl provided effective weed control that persisted more than 1 year with only partial injury to red clover populations. Grazing in concert with herbicide applications improves herbicide selectivity of preferentially grazed species, while improved from conventional standards practicality to producers is still unknown
The role of space borne imaging radars in environmental monitoring: Some shuttle imaging radar results in Asia
The synoptic view afforded by orbiting Earth sensors can be extremely valuable for resource evaluation, environmental monitoring and development planning. For many regions of the world, however, cloud cover has prevented the acquisition of remotely sensed data during the most environmentally stressful periods of the year. This paper discusses how synthetic aperture imaging radar can be used to provide valuable data about the condition of the Earth's surface during periods of bad weather. Examples are given of applications using data from the Shuttle Imaging Radars (SIR) A and B for agriculture land use and crop condition assessment, monsoon flood boundary and flood damage assessment, water resource monitoring and terrain modeling, coastal forest mapping and vegetation penetration, and coastal development monitoring. Recent SIR-B results in Bangladesh are emphasized, radar system basics are reviewed and future SAR systems discussed
Reducing False Alarms of Intensive Care Online-Monitoring Systems: An Evaluation of Two Signal Extraction Algorithms
Online-monitoring systems in intensive care are affected by a high rate of false threshold alarms. These are caused by irrelevant noise and outliers in the measured time series data. The high false alarm rates can be lowered by separating relevant signals from noise and outliers online, in such a way that signal estimations, instead of raw measurements, are compared to the alarm
limits. This paper presents a clinical validation study for two recently developed online signal filters. The filters are based on robust repeated median regression in moving windows of varying width. Validation is done offline using a large annotated reference database. The performance criteria are sensitivity and the proportion of false alarms suppressed by the signal filters
- …