The Experts below are selected from a list of 282 Experts worldwide ranked by ideXlab platform
Donald C. Hood - One of the best experts on this subject based on the ideXlab platform.
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Sites of cone System Sensitivity loss in retinitis pigmentosa.
Investigative Ophthalmology & Visual Science, 1993Co-Authors: William Seiple, Vivienne C. Greenstein, Karen Holopigian, Donald C. HoodAbstract:PURPOSE: To examine the sites of cone Sensitivity loss in patients with retinitis pigmentosa by comparing focal electroretinographic and psychophysical modulation thresholds. METHODS: Both psychophysical and electrophysiologic increment threshold curves were obtained in retinitis pigmentosa patients and a group of age-matched, normally-sighted adults. RESULTS: The majority of the retinitis pigmentosa data could be accounted for by a vertical displacement of the normal curve. The retinitis pigmentosa patients showed similar patterns of cone Sensitivity losses using both techniques. CONCLUSIONS: The combined electrophysiologic and psychophysical results provide support for an outer retina locus for these cone Sensitivity losses. The data suggest that these deficits may be caused by a spatially independent loss of cone photoreceptors with normal adaptation properties in the remaining photoreceptors.
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Sites of cone System Sensitivity loss in retinitis pigmentosa.
Investigative Ophthalmology & Visual Science, 1993Co-Authors: William Seiple, Vivienne C. Greenstein, Karen Holopigian, Donald C. HoodAbstract:PURPOSE: To examine the sites of cone Sensitivity loss in patients with retinitis pigmentosa by comparing focal electroretinographic and psychophysical modulation thresholds. METHODS: Both psychophysical and electrophysiologic increment threshold curves were obtained in retinitis pigmentosa patients and a group of age-matched, normally-sighted adults. RESULTS: The majority of the retinitis pigmentosa data could be accounted for by a vertical displacement of the normal curve. The retinitis pigmentosa patients showed similar patterns of cone Sensitivity losses using both techniques. CONCLUSIONS: The combined electrophysiologic and psychophysical results provide support for an outer retina locus for these cone Sensitivity losses. The data suggest that these deficits may be caused by a spatially independent loss of cone photoreceptors with normal adaptation properties in the remaining photoreceptors.
William Seiple - One of the best experts on this subject based on the ideXlab platform.
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Sites of cone System Sensitivity loss in retinitis pigmentosa.
Investigative Ophthalmology & Visual Science, 1993Co-Authors: William Seiple, Vivienne C. Greenstein, Karen Holopigian, Donald C. HoodAbstract:PURPOSE: To examine the sites of cone Sensitivity loss in patients with retinitis pigmentosa by comparing focal electroretinographic and psychophysical modulation thresholds. METHODS: Both psychophysical and electrophysiologic increment threshold curves were obtained in retinitis pigmentosa patients and a group of age-matched, normally-sighted adults. RESULTS: The majority of the retinitis pigmentosa data could be accounted for by a vertical displacement of the normal curve. The retinitis pigmentosa patients showed similar patterns of cone Sensitivity losses using both techniques. CONCLUSIONS: The combined electrophysiologic and psychophysical results provide support for an outer retina locus for these cone Sensitivity losses. The data suggest that these deficits may be caused by a spatially independent loss of cone photoreceptors with normal adaptation properties in the remaining photoreceptors.
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Sites of cone System Sensitivity loss in retinitis pigmentosa.
Investigative Ophthalmology & Visual Science, 1993Co-Authors: William Seiple, Vivienne C. Greenstein, Karen Holopigian, Donald C. HoodAbstract:PURPOSE: To examine the sites of cone Sensitivity loss in patients with retinitis pigmentosa by comparing focal electroretinographic and psychophysical modulation thresholds. METHODS: Both psychophysical and electrophysiologic increment threshold curves were obtained in retinitis pigmentosa patients and a group of age-matched, normally-sighted adults. RESULTS: The majority of the retinitis pigmentosa data could be accounted for by a vertical displacement of the normal curve. The retinitis pigmentosa patients showed similar patterns of cone Sensitivity losses using both techniques. CONCLUSIONS: The combined electrophysiologic and psychophysical results provide support for an outer retina locus for these cone Sensitivity losses. The data suggest that these deficits may be caused by a spatially independent loss of cone photoreceptors with normal adaptation properties in the remaining photoreceptors.
Karen Holopigian - One of the best experts on this subject based on the ideXlab platform.
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Sites of cone System Sensitivity loss in retinitis pigmentosa.
Investigative Ophthalmology & Visual Science, 1993Co-Authors: William Seiple, Vivienne C. Greenstein, Karen Holopigian, Donald C. HoodAbstract:PURPOSE: To examine the sites of cone Sensitivity loss in patients with retinitis pigmentosa by comparing focal electroretinographic and psychophysical modulation thresholds. METHODS: Both psychophysical and electrophysiologic increment threshold curves were obtained in retinitis pigmentosa patients and a group of age-matched, normally-sighted adults. RESULTS: The majority of the retinitis pigmentosa data could be accounted for by a vertical displacement of the normal curve. The retinitis pigmentosa patients showed similar patterns of cone Sensitivity losses using both techniques. CONCLUSIONS: The combined electrophysiologic and psychophysical results provide support for an outer retina locus for these cone Sensitivity losses. The data suggest that these deficits may be caused by a spatially independent loss of cone photoreceptors with normal adaptation properties in the remaining photoreceptors.
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Sites of cone System Sensitivity loss in retinitis pigmentosa.
Investigative Ophthalmology & Visual Science, 1993Co-Authors: William Seiple, Vivienne C. Greenstein, Karen Holopigian, Donald C. HoodAbstract:PURPOSE: To examine the sites of cone Sensitivity loss in patients with retinitis pigmentosa by comparing focal electroretinographic and psychophysical modulation thresholds. METHODS: Both psychophysical and electrophysiologic increment threshold curves were obtained in retinitis pigmentosa patients and a group of age-matched, normally-sighted adults. RESULTS: The majority of the retinitis pigmentosa data could be accounted for by a vertical displacement of the normal curve. The retinitis pigmentosa patients showed similar patterns of cone Sensitivity losses using both techniques. CONCLUSIONS: The combined electrophysiologic and psychophysical results provide support for an outer retina locus for these cone Sensitivity losses. The data suggest that these deficits may be caused by a spatially independent loss of cone photoreceptors with normal adaptation properties in the remaining photoreceptors.
Vivienne C. Greenstein - One of the best experts on this subject based on the ideXlab platform.
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Sites of cone System Sensitivity loss in retinitis pigmentosa.
Investigative Ophthalmology & Visual Science, 1993Co-Authors: William Seiple, Vivienne C. Greenstein, Karen Holopigian, Donald C. HoodAbstract:PURPOSE: To examine the sites of cone Sensitivity loss in patients with retinitis pigmentosa by comparing focal electroretinographic and psychophysical modulation thresholds. METHODS: Both psychophysical and electrophysiologic increment threshold curves were obtained in retinitis pigmentosa patients and a group of age-matched, normally-sighted adults. RESULTS: The majority of the retinitis pigmentosa data could be accounted for by a vertical displacement of the normal curve. The retinitis pigmentosa patients showed similar patterns of cone Sensitivity losses using both techniques. CONCLUSIONS: The combined electrophysiologic and psychophysical results provide support for an outer retina locus for these cone Sensitivity losses. The data suggest that these deficits may be caused by a spatially independent loss of cone photoreceptors with normal adaptation properties in the remaining photoreceptors.
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Sites of cone System Sensitivity loss in retinitis pigmentosa.
Investigative Ophthalmology & Visual Science, 1993Co-Authors: William Seiple, Vivienne C. Greenstein, Karen Holopigian, Donald C. HoodAbstract:PURPOSE: To examine the sites of cone Sensitivity loss in patients with retinitis pigmentosa by comparing focal electroretinographic and psychophysical modulation thresholds. METHODS: Both psychophysical and electrophysiologic increment threshold curves were obtained in retinitis pigmentosa patients and a group of age-matched, normally-sighted adults. RESULTS: The majority of the retinitis pigmentosa data could be accounted for by a vertical displacement of the normal curve. The retinitis pigmentosa patients showed similar patterns of cone Sensitivity losses using both techniques. CONCLUSIONS: The combined electrophysiologic and psychophysical results provide support for an outer retina locus for these cone Sensitivity losses. The data suggest that these deficits may be caused by a spatially independent loss of cone photoreceptors with normal adaptation properties in the remaining photoreceptors.
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Effects of early diabetic retinopathy on rod System Sensitivity
Optometry and vision science : official publication of the American Academy of Optometry, 1993Co-Authors: Vivienne C. Greenstein, Shari R. Thomas, Howard Blaustein, Karen L. Koenig, Ronald E. CarrAbstract:Previous studies have shown that S-cone pathway Sensitivity is selectively decreased in the early stages of diabetic retinopathy. In the present study, rod System Sensitivity was evaluated in a group of diabetic patients using psychophysical techniques. The course of dark adaptation was first determined, then absolute thresholds were measured in the horizontal and vertical meridians. For all patients, although the recovery of the initial portions of rod dark adaptation were normal, absolute thresholds were increased in both the horizontal and vertical meridians. The findings provide evidence that patients with early diabetic retinopathy show a generalized dysfunction of the rod System.
Junbo Zhang - One of the best experts on this subject based on the ideXlab platform.
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IECON - Power System Sensitivity Matrix Estimation by Multivariable Least Squares Considering Mitigating Data Saturation
IECON 2020 The 46th Annual Conference of the IEEE Industrial Electronics Society, 2020Co-Authors: Yingqi Liang, Junbo Zhang, Dipti SrinivasanAbstract:To online estimate the power System Sensitivity matrix considering mitigating data saturation, a series of multivariable least-squares (MLS) algorithms are proposed and compared, including the ordinary MLS (OMLS), the weighted MLS (WMLS), the memory-limited OMLS (ML-ORMLS), the memory-limited WRMLS (ML-WRMLS), and the memory-fading ML-WRMLS (MF-ML-WRMLS). Considering enhancing computational efficiency and accuracy by mitigating data saturation, the last three of them are specifically derived for Sensitivity matrix online estimation using online-measured data. The effectiveness of the presented algorithms is verified and compared in the Nordic 32 System for voltage Sensitivity matrix estimation. The results illustrate the prime algorithm in practice.
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Power System Sensitivity Matrix Estimation by Multivariable Least Squares Considering Mitigating Data Saturation
2020Co-Authors: Yingqi Liang, Junbo Zhang, Dipti SrinivasanAbstract:<div>To data-driven estimate power System Sensitivity matrix considering mitigating data saturation, a series of multivariable least squares (MLS) algorithms are proposed and compared, including the ordinary MLS (OMLS), the weighted MLS (WMLS), the memory-limited OMLS (ML-ORMLS), the memory-limited WRMLS (ML-WRMLS), and the memoryfading ML-WRMLS (MF-ML-WRMLS). Considering enhancing computational efficiency and accuracy by mitigating data saturation, the last three of them are specifically derived for Sensitivity matrix estimation based on time-varying online-measured data. The effectiveness of the presented algorithms is verified and compared in the Nordic 32 System for voltage Sensitivity matrix estimation. The results illustrate the prime algorithm in practice.</div>
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power System Sensitivity identification inherent System properties and data quality
IEEE Transactions on Power Systems, 2017Co-Authors: Junbo Zhang, Xiangtian Zheng, Zejing Wang, Lin Guan, Chi Yung ChungAbstract:The increasing amount of data recorded during power System operations and recently developed data-driven methods make online Sensitivity identification (SI) a possibility. However, due to the inherent properties of power Systems—nonlinearity, time variance, and collinearity—the effective data that carry the Sensitivity information are insufficient. Consequently, the online SI information collected with existing methods may result in unexpected estimates. In this paper, a sufficient effective data condition that guarantees the success of online SI is proposed. The inherent properties of power Systems and their impacts on this condition are then investigated. A series of metrics to qualify online whether the data meet the condition is put forward to assess the online SI results. A method is also proposed to select the effective data to improve the online computational efficiency. Finally, the findings and methods are validated in an eight-generator 36-node bus System with operations data recorded from actual power Systems.
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Power System Sensitivity Identification—Inherent System Properties and Data Quality
IEEE Transactions on Power Systems, 2017Co-Authors: Junbo Zhang, Xiangtian Zheng, Zejing Wang, Lin Guan, Chi Yung ChungAbstract:The increasing amount of data recorded during power System operations and recently developed data-driven methods make online Sensitivity identification (SI) a possibility. However, due to the inherent properties of power Systems—nonlinearity, time variance, and collinearity—the effective data that carry the Sensitivity information are insufficient. Consequently, the online SI information collected with existing methods may result in unexpected estimates. In this paper, a sufficient effective data condition that guarantees the success of online SI is proposed. The inherent properties of power Systems and their impacts on this condition are then investigated. A series of metrics to qualify online whether the data meet the condition is put forward to assess the online SI results. A method is also proposed to select the effective data to improve the online computational efficiency. Finally, the findings and methods are validated in an eight-generator 36-node bus System with operations data recorded from actual power Systems.
