The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform

Sharayu Moharir - One of the best experts on this subject based on the ideXlab platform.

  • SPCOM - Age-of-Information Aware Scheduling under Markovian Energy Arrivals
    2020 International Conference on Signal Processing and Communications (SPCOM), 2020
    Co-Authors: Bejjipuram Sombabu, Sharayu Moharir
    Abstract:

    We consider the task of scheduling updates from multiple sources to a Central Monitoring Station via a shared communication channel. Each source harvests energy from nature to measure a time-varying quantity and report these measurements to the Monitoring Station. Prior work in this area focuses on the setting where energy arrivals are assumed to be independent across time. Motivated by the time-correlation in energy generated by many renewable energy sources, we use a Markov process to model the energy arrivals. The goal is to minimize the time average of the weighted sum of the ages-of-information of the sources. We use Whittle’s relaxation and propose a modification of the Whittle Index to design a scheduling policy. We show that our policy outperforms other natural policies via simulations.

  • WiOpt - You Snooze, You Lose: Minimizing Channel-Aware Age of Information
    2020
    Co-Authors: Bhishma Dedhia, Sharayu Moharir
    Abstract:

    We propose a variant of the Age of Information (AoI) metric called Channel-Aware Age of Information (CA-AoI). Unlike AoI, CA-AoI takes into account the channel conditions between the source and the intended destination to compute the “age” of the recent most update received by the destination. We design scheduling policies for multi-sensor systems in which sensors report their measurements to a Central Monitoring Station via a shared unreliable communication channel with the goal of minimizing the time-average of the weighted sum of CA-AoIs. We show that the scheduling problem is indexable and derive low complexity Whittle index based scheduling policies. We also design randomized scheduling algorithms and give optimization procedures to find the optimal parameters of the policy. Via simulations, we show that our proposed policies surpass the greedy policy in several settings. Moreover the Whittle Index based scheduling policies outperform other policies in all the settings considered.

  • You Snooze, You Lose: Minimizing Channel-Aware Age of Information
    2020
    Co-Authors: Bhishma Dedhia, Sharayu Moharir
    Abstract:

    We propose a variant of the Age of Information (AoI) metric called Channel-Aware Age of Information (CA-AoI). Unlike AoI, CA-AoI takes into account the channel conditions between the source and the intended destination to compute the "age" of the recent most update received by the destination. We design scheduling policies for multi-sensor systems in which sensors report their measurements to a Central Monitoring Station via a shared unreliable communication channel with the goal of minimizing the time-average of the weighted sum of CA-AoIs. We show that the scheduling problem is indexable and derive low complexity Whittle index based scheduling policies. We also design randomized scheduling algorithms and give optimization procedures to find the optimal parameters of the policy. Via simulations, we show that our proposed policies surpass the greedy policy in several settings. Moreover the Whittle Index based scheduling policies outperform other policies in all the settings considered.

  • On Minimizing Channel-Aware Age of Information in a Multi-Sensor Setting
    2020
    Co-Authors: Bhishma Dedhia, Sharayu Moharir
    Abstract:

    We propose a variant of the Age of Information (AoI) metric called Channel-Aware Age of Information (CA-AoI). Unlike AoI, CA-AoI takes into account the channel conditions between the source and the intended destination to compute the "age" of the recent most update received by the destination. This new metric ensures that the resource allocation is not heavily titled towards the sources with poor channel conditions. We design scheduling policies for multi-sensor systems in which sensors report their measurements to a Central Monitoring Station via a shared unreliable communication channel with the goal of minimizing the time-average of the weighted sum of CA-AoIs. We initially derive universal lower bounds for the freshness objective. We show that the scheduling problem is indexable and derive low complexity Whittle index based scheduling policies. We also design Stationary randomized scheduling algorithms and give optimization procedures to find the optimal parameters of the policy. Via simulations, we show that our proposed policies surpass the greedy policy in several settings. Moreover the Whittle Index based scheduling policies outperform other policies in all the settings considered.

  • Age-of-Information Based Scheduling for Multi-Channel Systems
    IEEE Transactions on Wireless Communications, 2020
    Co-Authors: Bejjipuram Sombabu, Sharayu Moharir
    Abstract:

    We consider a system consisting of multiple sensors, a Central Monitoring Station, and multiple orthogonal frequency channels. The sensors measure heterogeneous time-varying signals and report their measurements to the Central Monitoring Station which uses them to make control decisions. Due to limited communication capacity, not all sensors can send updates to the Monitoring Station at all times. The cost the system pays is a function of the weighted sum of the ages-of-information of the various sensors over time. The goal is to design scheduling policies which minimize the time-average of this cost. We propose a policy called SQRT-Weight which fetches updates from sensors at a frequency proportional to the square-root of the corresponding weights and show that this policy is asymptotically 8-optimal. In addition, we compare the performance of the SQRT-Weight policy with other natural scheduling policies via simulations and through analysis for certain special cases.

Cristian Rotariu - One of the best experts on this subject based on the ideXlab platform.

  • A wireless sensor network for remote Monitoring of bioimpedance
    2015 38th International Spring Seminar on Electronics Technology (ISSE), 2015
    Co-Authors: Cristian Rotariu, Alexandru Păsărică, Radu Gabriel Bozomitu, Vlad Cehan, Hariton Costin
    Abstract:

    This paper describes the research for the design and realization of a flexible, scalable and cost-effective medical wireless measurement system for remote Monitoring of changes in patient's electrical bioimedance, based on wireless sensor networks. The bioimpedance is continuously measured using a custom developed wireless sensor node and then is wirelessly transferred to a remote Central Monitoring Station through a wireless sensor network. A user-friendly graphical user interface running on Monitoring Station was developed, to display the value received from the selected patient, and also the sensor node status. The proposed system may be used in many medical applications for remote Monitoring of patient's psycho-physiological processes, respiration frequency, assessing hydration status and visceral fat accumulation, or other skin related diseases, within healthcare institutes or their homes, with a high degree of accuracy similar to widely used commercial systems. The described system has been developed, implemented, and tested.

  • Real-Time System for Continuous and Remote Monitoring of Respiration during Sleep Using Wireless Sensors Networks
    International Conference on Advancements of Medicine and Health Care through Technology; 5th – 7th June 2014 Cluj-Napoca Romania, 2014
    Co-Authors: Cristian Rotariu, Alexandru Păsărică, Hariton Costin, Razvan Ciobotariu, Ciprian Cristea
    Abstract:

    Sleep represents a dynamic physiological process having an important role in the restoration of the Central nervous system. Nowadays, because a significant part of the population suffers of sleep disorders, the dynamic long time continuous Monitoring of human respiration has an important role in diagnosis and treatment. This paper proposes a flexible, scalable and cost-effective integrated system for respiration frequency Monitoring during sleep. The described system may be used to monitor especially patients suffering from obstructive sleep apnea episodes, within healthcare institutes or their homes, with a degree of accuracy similar to the most expansive commercial systems. Usually the long time continuous Monitoring requires the use of sensors attached by wires to the medical devices, but they are very uncomfortable for patient during sleep. As an alternative, the patient’s respiration frequency is continuously measured by using wireless sensor nodes and then transferred to a Central Monitoring Station via a wireless sensor network. The sensor nodes use devices based on the impedance pneumography technique to measure the patient respiration frequency connected to wireless modules. On the Central Monitoring Station a software application receives the patient’s respiration frequency from wireless sensors network, displays it on its graphical user interface and activates the alerts in interface when obstructive sleep apnea episodes are detected. A prototype of the described system has been developed, implemented and tested.

  • Wireless skin temperature measurement system for circadian rhythm Monitoring
    2013 E-Health and Bioengineering Conference (EHB), 2013
    Co-Authors: Cristian Rotariu, Harito Costi, Alexandru Păsărică, Cipria Cristea, Ogda Dionisie
    Abstract:

    Nowadays a significant part of the population suffers of sleep disorders, so the dynamic long term Monitoring of skin temperature during sleep is very useful for analysis and understanding the circadian rhythm. In this paper we describe the realization of a patient skin temperature Monitoring system, based on wireless devices, capable to measure and transmit the patient's skin temperature to a Central Monitoring Station. The use of the proposed system is suitable for remote continuous long-time patient Monitoring, in-hospital or at-home, as a part of a diagnostic procedure or during recovery. The described system uses custom developed wireless temperature measurement devices that perform the temperature measurements and wirelessly transmit them to the Monitoring Station. A graphical user interface running on the Central Monitoring Station was developed, used for displaying the measurements and alerts, when patient temperature values exceed the preset limits.

  • Remote respiration Monitoring system for sleep apnea detection.
    Revista medico-chirurgicală̆ a Societă̆ţ̜ii de Medici ş̧i Naturaliş̧ti din Iaş̧i, 2013
    Co-Authors: Cristian Rotariu, Hariton Costin
    Abstract:

    UNLABELLED Sleep is a dynamic physiological process, its primary function being the restoration of the Central nervous system. Because sleep disorders affect a significant part of the population the dynamic long term Monitoring of human respiration plays a very important role in diagnosis and treatment. MATERIAL AND METHODS We describe a remote Monitoring system designed for in-hospital or at-home detection with a high degree of accuracy of sleep-related disorders in patients experiencing episodes of obstructive sleep apnea. Patient's respiratory rate is continuously measured by using wireless devices and then transfered to a Central Monitoring Station via a wireless sensor network. The Central Monitoring Station runs a respiration Monitoring application that receives the patient's respiratory rate from the network and activates an alert upon detection of a sleep apnea episode. RESULTS A user-friendly graphical user interface was designed for the respiration Monitoring application that displays patient's respiratory rates and sleep apnea alerts. A prototype of the system has been developed, implemented and tested. CONCLUSIONS The described system allows persons with respiratory diseases or elderly to be monitored at their homes, as an alternative to medical supervision in hospitals.

  • FedCSIS - Wireless system for remote Monitoring of oxygen saturation and heart rate
    2012
    Co-Authors: Cristian Rotariu, Vasile Manta
    Abstract:

    This paper describes the realization of a wireless oxygen saturation and heart rate system for patient Monitoring in a limited area. The proposed system will allow the automatic remote Monitoring in hospitals, at home, at work, in real time, of persons with chronic illness, of elderly people, and of those having high medical risk. The system can be used for long-time continuous patient Monitoring, as medical assistance of a chronic condition, as part of a diagnostic procedure, or recovery from an acute event. The blood oxygen saturation level (SpO 2 ) and heart rate (HR) are continuously measured using commercially available pulse oximeters and then transferred to a Central Monitoring Station via a wireless sensor network (WSN). The Central Monitoring Station runs a patient monitor application that receives the SpO 2 and HR from WSN, processes these values and activates the alarms when the results exceed the preset limits. A user-friendly Graphical User Interface was developed for the patient monitor application to display the received measurements from all monitored patients. A prototype of the system has been developed, implemented and tested.

Hariton Costin - One of the best experts on this subject based on the ideXlab platform.

  • A wireless sensor network for remote Monitoring of bioimpedance
    2015 38th International Spring Seminar on Electronics Technology (ISSE), 2015
    Co-Authors: Cristian Rotariu, Alexandru Păsărică, Radu Gabriel Bozomitu, Vlad Cehan, Hariton Costin
    Abstract:

    This paper describes the research for the design and realization of a flexible, scalable and cost-effective medical wireless measurement system for remote Monitoring of changes in patient's electrical bioimedance, based on wireless sensor networks. The bioimpedance is continuously measured using a custom developed wireless sensor node and then is wirelessly transferred to a remote Central Monitoring Station through a wireless sensor network. A user-friendly graphical user interface running on Monitoring Station was developed, to display the value received from the selected patient, and also the sensor node status. The proposed system may be used in many medical applications for remote Monitoring of patient's psycho-physiological processes, respiration frequency, assessing hydration status and visceral fat accumulation, or other skin related diseases, within healthcare institutes or their homes, with a high degree of accuracy similar to widely used commercial systems. The described system has been developed, implemented, and tested.

  • Real-Time System for Continuous and Remote Monitoring of Respiration during Sleep Using Wireless Sensors Networks
    International Conference on Advancements of Medicine and Health Care through Technology; 5th – 7th June 2014 Cluj-Napoca Romania, 2014
    Co-Authors: Cristian Rotariu, Alexandru Păsărică, Hariton Costin, Razvan Ciobotariu, Ciprian Cristea
    Abstract:

    Sleep represents a dynamic physiological process having an important role in the restoration of the Central nervous system. Nowadays, because a significant part of the population suffers of sleep disorders, the dynamic long time continuous Monitoring of human respiration has an important role in diagnosis and treatment. This paper proposes a flexible, scalable and cost-effective integrated system for respiration frequency Monitoring during sleep. The described system may be used to monitor especially patients suffering from obstructive sleep apnea episodes, within healthcare institutes or their homes, with a degree of accuracy similar to the most expansive commercial systems. Usually the long time continuous Monitoring requires the use of sensors attached by wires to the medical devices, but they are very uncomfortable for patient during sleep. As an alternative, the patient’s respiration frequency is continuously measured by using wireless sensor nodes and then transferred to a Central Monitoring Station via a wireless sensor network. The sensor nodes use devices based on the impedance pneumography technique to measure the patient respiration frequency connected to wireless modules. On the Central Monitoring Station a software application receives the patient’s respiration frequency from wireless sensors network, displays it on its graphical user interface and activates the alerts in interface when obstructive sleep apnea episodes are detected. A prototype of the described system has been developed, implemented and tested.

  • Remote respiration Monitoring system for sleep apnea detection.
    Revista medico-chirurgicală̆ a Societă̆ţ̜ii de Medici ş̧i Naturaliş̧ti din Iaş̧i, 2013
    Co-Authors: Cristian Rotariu, Hariton Costin
    Abstract:

    UNLABELLED Sleep is a dynamic physiological process, its primary function being the restoration of the Central nervous system. Because sleep disorders affect a significant part of the population the dynamic long term Monitoring of human respiration plays a very important role in diagnosis and treatment. MATERIAL AND METHODS We describe a remote Monitoring system designed for in-hospital or at-home detection with a high degree of accuracy of sleep-related disorders in patients experiencing episodes of obstructive sleep apnea. Patient's respiratory rate is continuously measured by using wireless devices and then transfered to a Central Monitoring Station via a wireless sensor network. The Central Monitoring Station runs a respiration Monitoring application that receives the patient's respiratory rate from the network and activates an alert upon detection of a sleep apnea episode. RESULTS A user-friendly graphical user interface was designed for the respiration Monitoring application that displays patient's respiratory rates and sleep apnea alerts. A prototype of the system has been developed, implemented and tested. CONCLUSIONS The described system allows persons with respiratory diseases or elderly to be monitored at their homes, as an alternative to medical supervision in hospitals.

Dinesh Bhatia - One of the best experts on this subject based on the ideXlab platform.

  • A Wireless Telemedicine System with Extended Reporting Range and Priority Messaging
    2007 IEEE Dallas Engineering in Medicine and Biology Workshop, 2007
    Co-Authors: Todd Polk, William Walker, Dinesh Bhatia
    Abstract:

    Extensions and enhancements are proposed for a previously developed system to remotely monitor patient vital signs. This previously developed network utilizes Crossbow MICAz motes to create a wireless network to gather data, which is sent to a Central Monitoring Station. It includes a graphical user interface to store and display incoming measurements for all patients being monitored. Here the range of the network is extended by interfacing a GSM modem to the wireless sensor base Station, allowing critical data to be forwarded anywhere in the world and providing a remote query mechanism via the existing cellular infrastructure. Text messaging using short message service is used as the communication interface. A priority message handling layer is added to the current protocol to insure delivery of critical data to the Monitoring Station and from there to medical personnel via the existing cellular infrastructure.

  • Remote Cardiac Activity Monitoring Using Multi-Hop Wireless Sensor Networks
    2007 IEEE Dallas Engineering in Medicine and Biology Workshop, 2007
    Co-Authors: J.p. Shah, Abhiman Hande, P. Aroul, Dinesh Bhatia
    Abstract:

    Pervasive human Monitoring of various biological parameters is a growing field of interest. The focus of this research is to provide a step forward towards pervasive health Monitoring. We describe a system to remotely monitor data from a patient's electrocardiogram (ECG). The data is transferred to a Central Monitoring Station via a wireless sensor network for display. Crossbow MICAz motes are used as the network nodes. One of the nodes is interfaced with a commercial 3-lead ECG module and others are used to route the data through the network. A graphical user interface is designed for Monitoring the cardiac rhythm. The primary objective of this experiment is to wirelessly transmit streaming ECG data in real-time with high reliability and minimal packet loss. Test results indicate a high reception ratio while transmitting ECG data over multiple hops.

  • Wireless telemetry for oxygen saturation measurements
    2006 IEEE Biomedical Circuits and Systems Conference, 2006
    Co-Authors: Todd Polk, William Walker, Abhiman Hande, Dinesh Bhatia
    Abstract:

    A system to remotely monitor a patient’s oxygen saturation (%SpO 2 ) levels is described. The data was continuously measured using a pulse oximeter and then transferred to a Central Monitoring Station via a wireless sensor network for storage and display. Crossbow MICAz motes were programmed to serve as the network nodes. One mote was interfaced to the pulse oximeter for data acquisition and the others were utilized to route the %SpO 2 data to the Monitoring Station. A user-friendly graphical user interface was developed to capture and display incoming measurements for all patients being monitored. Test results indicated high accuracy in the measurements.

N. Matsui - One of the best experts on this subject based on the ideXlab platform.

  • DSP- and GPS-based synchronized measurement system of harmonics in wide-area distribution system
    IEEE Transactions on Industrial Electronics, 2003
    Co-Authors: Hiroyuki Ukai, K. Nakamura, N. Matsui
    Abstract:

    With the recent progress in power electronics devices, harmonic pollution in the power system becomes a significant problem. Therefore, a great deal of attention has been paid to harmonic regulations and suppression technologies. As the utility power distribution system becomes broader and more complex, advanced harmonic measurement and analysis technologies are required. This paper presents the advanced measurement system of harmonics in a wide-area distribution system. The proposed measurement system has the following features. The measurement unit at each point in the distribution system consists of a digital signal processor as a high-speed processor and a global positioning system as a synchronization measurement. These units as terminals at multipoints in the distribution system are connected to the Central Monitoring Station by the Internet. By using this system, the harmonic flows in the distribution system are measured and, hence, harmonic modeling can be realized in real time.

  • Advanced synchronized measurement system of harmonics using DSP and GPS
    2000 26th Annual Conference of the IEEE Industrial Electronics Society. IECON 2000. 2000 IEEE International Conference on Industrial Electronics Contr, 2000
    Co-Authors: Hiroyuki Ukai, K. Nakamura, S. Nishigaki, Y. Ohta, N. Matsui
    Abstract:

    A great deal of attention has been paid to harmonic regulations and suppression technologies in power systems. For this purpose many-researchers with respect to passive and active filters have been reported. As utility power distribution systems become broader and more complex, however, advanced harmonic measurement and analysis technologies are required. This paper presents the developed measurement system of harmonics. The system consists of DSP (digital signal processor) as the high speed processor and GPS (Global Positioning System) as synchronization measurement. The broad measurement system is proposed by assigning these systems as terminals at multi-points in the power distribution system and connecting those and Central Monitoring Station by the Internet.