Photoplethysmography and its application in clinical physiological measurement

http://www.kresttechnology.com/krest-academic-projects/krest-major-projects/ECE/B-Tech%20Papers/67.pdf

ECG signal denoising and baseline wander correction based on the empirical mode decomposition

Oscillating-water-column wave energy converters and air turbines: A review

McDonaldʼs Blood Flow in Arteries

Photoplethysmography (PPG) is a noninvasive optical technique for detecting microvascular blood volume changes in tissues. Its ease of use, low cost and convenience make it an attractive area of research in the biomedical and clinical communities. Nevertheless, its single spot monitoring and the need to apply a PPG sensor directly to the skin limit its practicality in situations such as perfusion mapping and healing assessments or when free movement is required. The introduction of fast digital cameras into clinical imaging monitoring and diagnosis systems, the desire to reduce the physical restrictions, and the possible new insights that might come from perfusion imaging and mapping inspired the evolution of the conventional PPG technology to imaging PPG (IPPG). IPPG is a noncontact method that can detect heart-generated pulse waves by means of peripheral blood perfusion measurements. Since its inception, IPPG has attracted significant public interest and provided opportunities to improve personal healthcare. This study presents an overview of the wide range of IPPG systems currently being introduced along with examples of their application in various physiological assessments. We believe that the widespread acceptance of IPPG is happening, and it will dramatically accelerate the promotion of this healthcare model in the near future.

/pdf/photoplethysmography-revisited-from-contact-to-noncontact-2jla840amb.pdf

Photoplethysmography Revisited: From Contact to Noncontact, From Point to Imaging

Steering ship models are important for the study of autonomous ship manoeuverability and design of ship motion control system. It is always a difficult task to find the mathematical model by first ...

Steering model identification and control design of autonomous ship: a complete experimental study

To administer regional block (local anesthesia) prior to an eye surgery, the anesthetist must insert the needle at the correct position and angle to avoid unnecessary injury to the eye. A training module wherein an anesthetist can be trained to properly administer anesthesia would avoid the risks involved in real life training. Such a training system, where the position and angle of insertion of the needle used to administer anesthesia are determined employing a capacitive sensor array with suitable signal conditioning and sensing logic is described in this paper. Simulation studies and test results on a prototype built and tested demonstrated the practicality of the proposed scheme. The proposed scheme is designed such that the sensing system can be installed easily into a commercially available mannequin and the mannequin used for training, thus dispensing with the need for custom fabrication.

A capacitive array sensing based training system for ophthalmic anesthesia

A successive approximation type direct displacement to digital converter suitable for a floating-wiper inductive displacement sensor is proposed here. The topology of a successive approximation type digital converter (SADC) is suitably altered so that a floating-wiper inductive displacement sensor becomes an integral part of the SADC. The successive approximation logic results in the final digital output directly proportional to the displacement of the floating wiper. The hardware and logic are so designed that the final digital output is independent of the interfering inputs. The results obtained from simulation studies establish the efficacy of the proposed technique.

Successive approximation type digital converter for floating-wiper inductive displacement sensor

A sensitive rapid Gas Chromatography with mass spectrometry (GC-MS) method has been developed and validated for the determination of 1-Bromopropane content in Divalproex sodium drug substance. 1-Bromopropane has been considered as a potential genotoxic impurity. The lower level of detection was achieved on fused silica capillary column coated with 100% dimethylpolysiloxane stationary phase with Electron Impact ionization (EI) in Selective Ion Monitoring (SIM) mode. GC runtime was 25min employing programmed temperature with split mode using head-space injection technique. The developed method was validated for specificity, linearity, accuracy and precision. The detection and quantitation limits of 1-Bromopropane obtained were 0.05 μg/g and 0.10 μg/g respectively. The method was found to be linear in the range between 0.10 μg/g and 0.75 μg/g with correlation coefficient 0.9999. The average recovery obtained in Divalproex sodium drug substance was 97.3%. The developed method was found to be rugged for the determination of 1-Bromopropane in divalproex sodium drug substance. The detailed approach of experiments is discussed in the paper

/pdf/quantification-of-potential-genotoxic-impurity-in-divalproex-4jaoxfweba.pdf

Quantification of potential genotoxic impurity in Divalproex sodium drug substance by GC-MS method.

Magneto plethysmo gram (MPG), like the Photo plethysmo gram (PPG) is a signal that carries information on blood volume flow and is obtained noninvasively. Unlike PPG, MPG is obtained from a peripheral artery, such as radial, carotid or brachial. The magnetic flux required for obtaining an MPG is generated by a permanent magnet placed on the wrist surface such that the generated flux couples with the blood flow in the artery. In this work it is shown that maximum coupling of flux with the blood flow in radial artery occurs when the distance between the open end of the U shaped probe is 12 mm. In order to attain this result, first the probe is simulated using the finite element method. The distance between the pole faces is varied in steps of 1 mm. Simulation results clearly indicate that the optimal distance is 12mm. Next experiments were conducted with prototype probes of varying distances between the pole faces on 20 volunteers of different age and gender. The experimental results validate the result obtained by the simulation study.

V. Jagadeesh Kumar

Papers

Steering model identification and control design of autonomous ship: a complete experimental study

A capacitive array sensing based training system for ophthalmic anesthesia

Successive approximation type digital converter for floating-wiper inductive displacement sensor

Quantification of potential genotoxic impurity in Divalproex sodium drug substance by GC-MS method.

Optimal Design to Ensure Maximum Coupling Between Magnetic Flux and Arterial Blood in a Magneto Plethysmo Gram Sensor Head