The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform
B Bauduceau - One of the best experts on this subject based on the ideXlab platform.
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screening of cardiovascular autonomic neuropathy in patients with diabetes using non invasive quick and simple assessment of sudomotor function
Diabetes & Metabolism, 2013Co-Authors: Chittaranjan S Yajnik, V Kantikar, Amol J Pande, J P Deslypere, J Dupin, J H Calvet, B BauduceauAbstract:Abstract Aim Cardiovascular autonomic neuropathy (CAN) is a common but often overlooked complication of diabetes. Sympathetic C-fibers innervating sweat glands can be impaired early on in patients with diabetes. In this study, SUDOSCAN, a new non-invasive device that assesses sudomotor function was compared to methods generally used for the investigation of CAN. Patients A total of 232 patients with diabetes were measured for heart rate variability (HRV) at rest and during moderate activity. Time and frequency Domain analysis techniques, including measurement of the low-frequency (LF) Domain Component, were assessed during HRV testing. Ewing tests, as recommended by the French Health Authority, were also done. Electrochemical sweat conductance (ESC) was measured on the hands and feet, and a risk-score was calculated. Results Using two abnormal Ewing tests as a reference for the area under the curve (AUC) of the receiver operating characteristics (ROC) curve for SUDOSCAN, the risk-score was 0.74, with a sensitivity of 92% and specificity of 49% for a risk-score cut-off value of 35%. For the ROC curve analysis using the LF power Component during moderate activity at a threshold of 90 ms 2 (first quartile) as reference, the AUC was higher for the SUDOSCAN risk-score (0.77) compared with the standard Ewing tests [E:I ratio (0.62), 30:15 ratio (0.76) and blood pressure change on standing (0.55)]. Using a cut-off value of 35%, risk-score sensitivity and specificity were 88 and 54%, respectively. Conclusion SUDOSCAN, which allows quick quantitative assessment of sudomotor function, may be used for early screening of CAN in everyday clinical practice before resorting to the more sophisticated and specific, but ultimately more time-consuming, Ewing tests.
Vahid Tarokh - One of the best experts on this subject based on the ideXlab platform.
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Near Shannon Limit and Low Peak to Average Power Ratio Turbo Block Coded OFDM
IEEE Transactions on Communications, 2011Co-Authors: Maryam Sabbaghian, Yongjun Kwak, Besma Smida, Vahid TarokhAbstract:In this paper, we present an advanced solution for the long standing problem of large peak to average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM) systems. Although the design of low PAPR codewords has been extensively studied and the existence of asymptotically good codes with low PAPR is also proven, still no code has been constructed to satisfy all requirements. The main goal of the paper is to develop a coding scheme that not only generates low PAPR codewords, but it also performs relatively close to the Shannon limit. We achieve this goal by implementing a time-frequency turbo block coded OFDM. In this scheme, we design the frequency Domain Component to have a tightly bounded PAPR. The time Domain Component code is designed to obtain good performance while the decoding algorithm has reasonable complexity. Through comparative performance evaluation we show that utilizing the proposed method, we achieve considerable improvement in terms of PAPR while we slightly loose the performance compared to capacity achieving codes with similar overall block length.
Hiroshi Amano - One of the best experts on this subject based on the ideXlab platform.
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the fourier transform of controlled source time Domain electromagnetic data by smooth spectrum inversion
Geophysical Journal International, 2001Co-Authors: Yuji Mitsuhata, Toshihiro Uchida, Yutaka Murakami, Hiroshi AmanoAbstract:SUMMARY In controlled-source electromagnetic measurements in the near zone or at low frequencies, the real (in-phase) frequency-Domain Component is dominated by the primary field. However, it is the imaginary (quadrature) Component that contains the signal related to a target deeper than the source–receiver separation. In practice, it is difficult to measure the imaginary Component because of the dominance of the primary field. In contrast, data acquired in the time Domain are more sensitive to the deeper target owing to the absence of the primary field. To estimate the frequency-Domain responses reliably from the time-Domain data, we have developed a Fourier transform algorithm using a least-squares inversion with a smoothness constraint (smooth spectrum inversion). In implementing the smoothness constraint as a priori information, we estimate the frequency response by maximizing the a posteriori distribution based on Bayes' rule. The adjustment of the weighting between the data misfit and the smoothness constraint is accomplished by minimizing Akaike's Bayesian Information Criterion (ABIC). Tests of the algorithm on synthetic and field data for the long-offset transient electromagnetic method provide reasonable results. The algorithm can handle time-Domain data with a wide range of delay times, and is effective for analysing noisy data.
Huiyou Chang - One of the best experts on this subject based on the ideXlab platform.
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reusable Components retrieval based on faceted classification with sem library in Domain Component library
International Conference on Interoperability for Enterprise Software and Applications China, 2009Co-Authors: Huiyou ChangAbstract:Faceted classification with strong extensibility has been widely used in the classification and retrieval of Component library. However, owing to its hierarchy structure, it lacks of understanding of the Domain knowledge in Domain Component library. Aimed at solving this problem, this paper proposes a Sem-library to provide effective keyword proximity queries to express abundant Domain knowledge in Domain Component library and release the users from esoteric vocabulary. Sem-Library supports basic semantic relationships and incremental query construction. Moreover, it is feasible and extensible for more complicated semantic relationships.
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IESA - Reusable Components Retrieval Based on Faceted Classification with Sem-library in Domain Component Library
2009 International Conference on Interoperability for Enterprise Software and Applications China, 2009Co-Authors: Huiyou ChangAbstract:Faceted classification with strong extensibility has been widely used in the classification and retrieval of Component library. However, owing to its hierarchy structure, it lacks of understanding of the Domain knowledge in Domain Component library. Aimed at solving this problem, this paper proposes a Sem-library to provide effective keyword proximity queries to express abundant Domain knowledge in Domain Component library and release the users from esoteric vocabulary. Sem-Library supports basic semantic relationships and incremental query construction. Moreover, it is feasible and extensible for more complicated semantic relationships.
Chittaranjan S Yajnik - One of the best experts on this subject based on the ideXlab platform.
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screening of cardiovascular autonomic neuropathy in patients with diabetes using non invasive quick and simple assessment of sudomotor function
Diabetes & Metabolism, 2013Co-Authors: Chittaranjan S Yajnik, V Kantikar, Amol J Pande, J P Deslypere, J Dupin, J H Calvet, B BauduceauAbstract:Abstract Aim Cardiovascular autonomic neuropathy (CAN) is a common but often overlooked complication of diabetes. Sympathetic C-fibers innervating sweat glands can be impaired early on in patients with diabetes. In this study, SUDOSCAN, a new non-invasive device that assesses sudomotor function was compared to methods generally used for the investigation of CAN. Patients A total of 232 patients with diabetes were measured for heart rate variability (HRV) at rest and during moderate activity. Time and frequency Domain analysis techniques, including measurement of the low-frequency (LF) Domain Component, were assessed during HRV testing. Ewing tests, as recommended by the French Health Authority, were also done. Electrochemical sweat conductance (ESC) was measured on the hands and feet, and a risk-score was calculated. Results Using two abnormal Ewing tests as a reference for the area under the curve (AUC) of the receiver operating characteristics (ROC) curve for SUDOSCAN, the risk-score was 0.74, with a sensitivity of 92% and specificity of 49% for a risk-score cut-off value of 35%. For the ROC curve analysis using the LF power Component during moderate activity at a threshold of 90 ms 2 (first quartile) as reference, the AUC was higher for the SUDOSCAN risk-score (0.77) compared with the standard Ewing tests [E:I ratio (0.62), 30:15 ratio (0.76) and blood pressure change on standing (0.55)]. Using a cut-off value of 35%, risk-score sensitivity and specificity were 88 and 54%, respectively. Conclusion SUDOSCAN, which allows quick quantitative assessment of sudomotor function, may be used for early screening of CAN in everyday clinical practice before resorting to the more sophisticated and specific, but ultimately more time-consuming, Ewing tests.