The Experts below are selected from a list of 279 Experts worldwide ranked by ideXlab platform

Ramesh P Singh - One of the best experts on this subject based on the ideXlab platform.

  • enhancement of oceanic parameters associated with dust storms using satellite data
    Journal of Geophysical Research, 2008
    Co-Authors: Vinay K Kayetha, Anup K Prasad, Ramesh P Singh, Menas Kafatos
    Abstract:

    over the Arabian Sea causes chlorophyll blooming (usually 10–22.43 mg/m 3 ) within a period of 1–2 to up to 3–4 days. However, we have also found significant anomalous cooling of the ocean surface (SST) and relatively higher ocean wind speeds (QuikSCAT) during dust storms that may lead to favorable conditions for blooming. Exact nature and cause of chlorophyll bloom in the semienclosed northern Arabian Sea, surrounded by one of the world’s major sources of dust storms (Africa, Middle East, Iran, and Afghanistan), are very important in understanding the productivity and the biogeochemical cycles of the marine ecosystem. The results have been validated using the Indian Remote Sensing Polar-4 Ocean Color Monitor (IRS P4 OCM) data.

  • Comparison of aerosol radiative forcing over the Arabian Sea and the Bay of Bengal
    Advances in Space Research, 2004
    Co-Authors: Sagnik Dey, Sudipta Sarkar, Ramesh P Singh
    Abstract:

    Abstract Aerosols play an important role in controlling the earth’s radiation budget, which influence the climatic processes. Marine aerosols are the single largest contributor of the aerosol optical depth. Ocean Color Monitor data onboard Indian Remote Sensing Satellite Polar Series 4 (IRS-P4) has been analyzed to retrieve the aerosol parameters over the Arabian Sea and the Bay of Bengal. Top of the Atmosphere (TOA) and the surface forcing have been deduced over the Arabian Sea and the Bay of Bengal. The nature of the aerosol forcing and seasonal effects over the Bay of Bengal and the Arabian Sea have been compared. Surface forcing shows strong seasonal influence, which has not been found on the TOA forcing. In general, higher forcing over the atmosphere has been observed over the Bay of Bengal (−30 to −54 W/m2) compared to those over the Arabian Sea (−26 to −48 W/m2). During the winter season, the surface forcing over the Arabian Sea (−28 to −45 W/m2) is observed to be higher than the Bay of Bengal (−25 to −38 W/m2).

  • Comparison of chlorophyll distributions in the northeastern Arabian Sea and southern Bay of Bengal using IRS-P4 Ocean Color Monitor data
    Remote Sensing of Environment, 2003
    Co-Authors: Sagnik Dey, Ramesh P Singh
    Abstract:

    Water masses of different temperature and salinity partially govern the distributions of chlorophyll concentration. In the present paper, chlorophyll concentration has been deduced over the northeastern Arabian Sea and the southern Bay of Bengal using Ocean Color Monitor (OCM) data onboard Indian Remote Sensing Series Polar satellite (IRS-P4). The chlorophyll concentration is found to be higher in the northeastern Arabian Sea compared to those in the southern Bay of Bengal. The higher chlorophyll concentration is found during the northeast monsoon compared to those during the pre- and post-monsoon period and also in the coastal water compared to the open ocean. Higher spatial and seasonal chlorophyll distributions in the northeastern Arabian Sea compared to the southern Bay of Bengal is attributed to the shallow depth of the shelf in the Arabian Sea.

Kristina Hellén-halme - One of the best experts on this subject based on the ideXlab platform.

  • Effect of two X-ray tube voltages on detection of approximal caries in digital radiographs. An in vitro study
    Clinical Oral Investigations, 2011
    Co-Authors: Kristina Hellén-halme
    Abstract:

    This study evaluated the effect of two different tube voltages on clinicians’ ability to diagnose approximal carious lesions in digital radiographs. One hundred extracted teeth were radiographed twice at two voltage settings, 60 and 70 kV, using a standardized procedure. Seven observers evaluated the radiographs on a standard Color Monitor pre-calibrated according to DICOM part 14. Evaluations were made at ambient light levels below 50 lx. All observations were analyzed with receiver operating characteristic curves. A histological examination of the teeth served as the criterion standard. A paired t test compared the effects of the two voltages. The significance level was set to p  

  • Effect of Monitors on approximal caries detection in digital radiographs--standard versus precalibrated DICOM part 14 displays: an in vitro study.
    Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 2009
    Co-Authors: Kristina Hellén-halme, Mats Nilsson, Arne Petersson
    Abstract:

    Objectives The aim of this study was to evaluate if different ways of adjusting brightness and contrast of Monitors with different technical standards influence the diagnosis of carious lesions in digital radiographs. Study design One hundred extracted teeth (premolars and molars) were radiographed. Seven observers evaluated images for approximal carious lesions on 3 Monitors: a standard Color Monitor with brightness and contrast manually adjusted for viewing radiographs, a Digital Imaging and Communication in Medicine (DICOM) part 14 precalibrated Color Monitor, and a DICOM part 14 precalibrated monochromatic Monitor. All evaluations were made in ambient light Results No significant difference in accuracy of approximal carious lesion diagnosis was found between the Monitors. Intraobserver agreement varied between fair and good. Conclusion No differences that could affect clinicians' abilities to detect carious lesions in digital radiographs existed between the standard Monitor and the Color and monochrome DICOM part 14 precalibrated Monitors.

Menas Kafatos - One of the best experts on this subject based on the ideXlab platform.

  • enhancement of oceanic parameters associated with dust storms using satellite data
    Journal of Geophysical Research, 2008
    Co-Authors: Vinay K Kayetha, Anup K Prasad, Ramesh P Singh, Menas Kafatos
    Abstract:

    over the Arabian Sea causes chlorophyll blooming (usually 10–22.43 mg/m 3 ) within a period of 1–2 to up to 3–4 days. However, we have also found significant anomalous cooling of the ocean surface (SST) and relatively higher ocean wind speeds (QuikSCAT) during dust storms that may lead to favorable conditions for blooming. Exact nature and cause of chlorophyll bloom in the semienclosed northern Arabian Sea, surrounded by one of the world’s major sources of dust storms (Africa, Middle East, Iran, and Afghanistan), are very important in understanding the productivity and the biogeochemical cycles of the marine ecosystem. The results have been validated using the Indian Remote Sensing Polar-4 Ocean Color Monitor (IRS P4 OCM) data.

Shigeru Saito - One of the best experts on this subject based on the ideXlab platform.

Koichi Nishikawa - One of the best experts on this subject based on the ideXlab platform.