ESTIMATION OF RESPIRATORY RATE FROM ECG

Clinical investigation of some sleep disorders, stress testing, ambulatory monitoring requires simultaneous monitoring of heart rate and respiratory rates. [3] Numerous methods have been reported for deriving respiratory information from the electrocardiogram (ECG). [1] Initially ECG signal is sent to microcontroller AT89S52 through ADC0848. The digital samples are once again transmitted to personal computer via a cable. The digital data is read with the help of graphical user interface software – Visual C++ (serial port programming). The data is stored in an array and the QRS peaks per minute are detected & heart rate is calculated. As these QRS peaks consist of respiratory information, an algorithm will be applied onto the QRS data to find the number of slopes per minute, which gives the respiratory rate. Hence the Heart Rate & Respiratory Rate per minute will be calculated and displayed real time on PC

Wearable contactless respiration sensor based on multi-material fibers integrated into textile

In this paper, we report on a novel sensor for the contactless monitoring of the respiration rate, made from multi-material fibers arranged in the form of spiral antenna (2.45 GHz central frequency). High flexibility of the used composite metal-glass-polymer fibers permits their integration into a cotton t-shirt without compromising comfort or restricting movement of the user. At the same time, change of the antenna geometry, due to the chest expansion and the displacement of the air volume in the lungs, is found to cause a significant shift of the antenna operational frequency, thus allowing respiration detection. In contrast with many current solutions, respiration is detected without attachment of the electrodes of any kind to the user’s body, neither direct contact of the fiber with the skin is required. Respiration patterns for two male volunteers were recorded with the help of a sensor prototype integrated into standard cotton t-shirt in sitting, standing, and lying scenarios. The typical measured frequency shift for the deep and shallow breathing was found to be in the range 120–200 MHz and 10–15 MHz, respectively. The same spiral fiber antenna is also shown to be suitable for short-range wireless communication, thus allowing respiration data transmission, for example, via the Bluetooth protocol, to mobile handheld devices

Evaluation of a wearable device to determine cardiorespiratory parameters from surface diaphragm electromyography

Using wearable devices in clinical routines could reduce healthcare costs and improve the quality of assessment in patients with chronic respiratory diseases. The purpose of this study is to evaluate the capability of a Shimmer3 wearable device device to extract reliable cardiorespiratory parameters from surface diaphragm electromyography (EMGdi). Twenty healthy volunteers underwent an incremental load respiratory test whilst EMGdi was recorded with a Shimmer3 wearable device (EMGdiW). Simultaneously, a second EMGdi (EMGdiL), the inspiratory mouth pressure (Pmouth) and the lead-I electrocardiogram (ECG) were recorded via a standard wired laboratory acquisition system. Different cardiorespiratory parameters have been extracted from both EMGdiW and EMGdiL signals.: heart rate, respiratory rate, respiratory muscle activity and mean frequency of EMGdi signals. Alongside these, similar parameters were also extracted from reference signals (Pmouth and ECG). High correlations were found between the data extracted from the EMGdiW and the reference signal data: heart rate (R = 0.947), respiratory rate (R = 0.940), respiratory muscle activity (R = 0.877), and mean frequency (R = 0.895). Moreover, similar increments in EMGdiW and EMGdiL activity were observed when Pmouth was raised, enabling the study of respiratory muscle activation. In summary, the Shimmer3 device is a promising and cost-effective solution for ambulatory monitoring of respiratory muscle function in chronic respiratory diseases.Postprint (author's final draft

Unobtrusive Monitoring of Heart Rate and Respiration Rate during Sleep

Sleep deprivation has various adverse psychological and physiological effects. The effects range from decreased vigilance causing an increased risk of e.g. traffic accidents to a decreased immune response causing an increased risk of falling ill. Prevalence of the most common sleep disorder, insomnia can be, depending on the study, as high as 30 % in adult population. Physiological information measured unobtrusively during sleep can be used to assess the quantity and the quality of sleep by detecting sleeping patterns and possible sleep disorders. The parameters derived from the signals measured with unobtrusive sensors may include all or some of the following: heartbeat intervals, respiration cycle lengths, and movements. The information can be used in wellness applications that include self-monitoring of the sleep quality or it can also be used for the screening of sleep disorders and in following-up of the effect of a medical treatment. Unobtrusive sensors do not cause excessive discomfort or inconvenience to the user and are thus suitable for long-term monitoring. Even though the monitoring itself does not solve the sleeping problems, it can encourage the users to pay more attention on their sleep. While unobtrusive sensors are convenient to use, their common drawback is that the quality of the signals they produce is not as good as with conventional measurement methods. Movement artifacts, for example, can make the detection of the heartbeat intervals and respiration impossible. The accuracy and the availability of the physiological information extracted from the signals however depend on the measurement principle and the signal analysis methods used. Three different measurement systems were constructed in the studies included in the thesis and signal processing methods were developed for detecting heartbeat intervals and respiration cycle lengths from the measured signals. The performance of the measurement systems and the signal analysis methods were evaluated separately for each system with healthy young adult subjects. The detection of physiological information with the three systems was based on the measurement of ballistocardiographic and respiration movement signals with force sensors placed under the bedposts, the measurement of electrocardiographic (ECG) signal with textile electrodes attached to the bed sheet, and the measurement of the ECG signal with non-contact capacitive electrodes. Combining the information produced by different measurement methods for improving the detection performance was also tested. From the evaluated methods, the most accurate heartbeat interval information was obtained with contact electrodes attached to the bed sheet. The same method also provided the highest heart rate detection coverage. This monitoring method, however, has a limitation that it requires a naked upper body, which is not necessarily acceptable for everyone. For respiration cycle length detection, better results were achieved by using signals recorded with force sensors placed under a bedpost than when extracting the respiration information from the ECG signal recorded with textile bed sheet electrodes. From the data quality point of view, an ideal night-time physiological monitoring system would include a contact ECG measurement for the heart rate monitoring and force sensors for the respiration monitoring. The force sensor signals could also be used for movement detection

Obstrüktif uyku apne teşhisi için makine öğrenmesi tabanlı yeni bir yöntem geliştirilmesi

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Obstrüktif Uyku Apne (OSA) uykuda solunumun durmasına bağlı olarak ortaya çıkan bir hastalıktır. Hastalığın teşhisi polisomnografi (PSG) cihazı kullanılarak uyku evreleme ve solunum skorlama adımları ile gerçekleştirilir. Sistem yapısı gereği teşhis sırasında hastaya birçok rahatsızlık vermektedir. Verilen rahatsızlıklara çözüm olabilecek, PSG cihazına alternatif sistemlere ihtiyaç duyulmaktadır. Bu tez çalışmasında, PSG cihazına alternatif yeni bir yaklaşım geliştirilmiştir. Bu yaklaşım ile PSG'ye alternatif, hastaya daha az rahatsızlık veren ve PSG kadar güvenilir bir cihazın oluşturulabileceği ispatlanmıştır. Çalışmada, 10 bireyden alınan Fotopletismografi (PPG) sinyali kullanılmıştır. Teşhis için PPG sinyali ve bu sinyalden türetilen Kalp Hızı Değişkeni (HRV) kullanılarak yapay zeka tabanlı teşhis algoritması tasarlanmıştır. Çalışma için PPG'den 46, HRV'den 40 adet olmak üzere toplam 86 özellik çıkarılmıştır. Çıkarılan özelliklerin, Mann-Whitney U Testi yöntemiyle, istatistiksel olarak, uyku uyanıklık ve anormal solunumsal olaylar (apne var - yok) için ayırt edici olup olmadığı tespit edilmeye çalışılmıştır. Ayrıca, özellikler, F-score özellik seçme yöntemleriyle 2 defa azaltılmış ve sınıflandırılmıştır. İstatistiksel sonuçlara göre, uyku evreleme işlemi için, 86 özellikten 75'inin uyku uyanıklık için anlamlı olduğu (p<0,05), solunum skorlamada ise 58 özelliğin anlamlı olduğu (p<0,05) tespit edilmiştir. Sınıflandırma sonuçlarına göre uyku evreleme 11 özellik ile, %84,93 duyarlılık, %97,40 özgüllük ve %91,09 sınıflandırma doğruluk oranı ile topluluk sınıflandırıcısı yardımıyla başarı ile sınıflandırılmıştır. Solunum skorlama işlemi, 86 özellik ile, %87,78 duyarlılık, %95,46 özgüllük ve %92,54 doğruluk oranı ile başarıyla gerçekleştirilmiştir. Bu çalışmada elde edilen sonuçlara göre, PPG sinyali ve bu sinyalden türetilen HRV özelliklerinin uyku evreleme ve solunum skorlama işleminde kullanılabileceği ve anlamlı sonuçlar vereceği kanısına varılmıştır. PPG sinyalinin kolay elde edilebilmesi ve HRV'nin PPG sinyalinden türetilmesi tek sinyal ile uyku evreleme ve solunum skorlama işleminin yapılabilmesinin önünü açmaktadır. Gerçek zamanlı çalışabilecek sistemlerde sinyalin kolay ölçülebilir ve kolay işlenebilir olması sistemlerin pratikliğini arttıracaktır.Obstructive Sleep Apnea (OSA) is a disease caused by breathlessness in sleep. Diagnosis of the disease is performed by polysomnography (PSG) device with sleep staging and respiratory scoring steps. The system structure causes many discomfort to the patient during diagnosis. Alternative systems are needed for the PSG device, which can be a solution to the inconveniences. In this thesis study, a new approach was developed to PSG device. This approach has been proven that an alternative to PSG is to create a device that is less disturbing to the patient and as reliable as PSG. In the study, a Photoplethysmography (PPG) signal from 10 individuals was used. For diagnosis, an artificial intelligence-based diagnostic algorithm is designed using PPG signal and Heart Rate Variable (HRV) derived from PPG. For the study, 86 features were extracted, 46 of PPG and 40 of HRV. Statistically, the Mann-Whitney U test was used to determine whether the extracted features were discriminatory for sleep – wakefulness and abnormal respiratory events (apnea present - absent). In addition, features are reduced by F-score property selection methods 2 times and classified. According to the statistical results, 75 of the 86 features were significant for sleep awake (p<0,05) and 58 for respiratory scoring (p<0,05). According to the classification results, the sleep classification was successfully classified with the help of ensemble classifier with 11 features, 84,93% sensitivity, 97,40% specificity and 91,09% classification accuracy. Respiratory scoring was successfully performed with 86 features with 87,78% sensitivity, 95.46% specificity and 92.54% classification accuracy. According to the results obtained in this study, it was concluded that features of the PPG signal and the HRV derived from PPG can be used in the sleep staging and respiratory scoring process and have meaningful results. The easy acquisition of the PPG signal and the derivation of the HRV from the PPG signal opens up the possibility of performing sleep staging and respiratory scoring with a single signal. In systems that can operate in real time, easy measurement and easy handling of the signal will increase the practicality of the systems

Application priority framework for fixed mobile converged communication networks

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.The current prospects in wired and wireless access networks, it is becoming increasingly important to address potential convergence in order to offer integrated broadband services. These systems will need to offer higher data transmission capacities and long battery life, which is the catalyst for an everincreasing variety of air interface technologies targeting local area to wide area connectivity. Current integrated industrial networks do not offer application aware context delivery and enhanced services for optimised networks. Application aware services provide value-added functionality to business applications by capturing, integrating, and consolidating intelligence about users and their endpoint devices from various points in the network. This thesis mainly intends to resolve the issues related to ubiquitous application aware service, fair allocation of radio access, reduced energy consumption and improved capacity. A technique that measures and evaluates the data rate demand to reduce application response time and queuing delay for multi radio interfaces is proposed. The technique overcomes the challenges of network integration, requiring no user intervention, saving battery life and selecting the radio access connection for the application requested by the end user. This study is split in two parts. The first contribution identifies some constraints of the services towards the application layer in terms of e.g. data rate and signal strength. The objectives are achieved by application controlled handover (ACH) mechanism in order to maintain acceptable data rate for real-time application services. It also looks into the impact of the radio link on the application and identifies elements and parameters like wireless link quality and handover that will influence the application type. It also identifies some enhanced traditional mechanisms such as distance controlled multihop and mesh topology required in order to support energy efficient multimedia applications. The second contribution unfolds an intelligent application priority assignment mechanism (IAPAM) for medical applications using wireless sensor networks. IAPAM proposes and evaluates a technique based on prioritising multiple virtual queues for the critical nature of medical data to improve instant transmission. Various mobility patterns (directed, controlled and random waypoint) has been investigated and compared by simulating IAPAM enabled mobile BWSN. The following topics have been studied, modelled, simulated and discussed in this thesis: 1. Application Controlled Handover (ACH) for multi radios over fibre 2. Power Controlled Scheme for mesh multi radios over fibre using ACH 3. IAPAM for Biomedical Wireless Sensor Networks (BWSN) and impact of mobility over IAPAM enabled BWSN. Extensive simulation studies are performed to analyze and to evaluate the proposed techniques. Simulation results demonstrate significant improvements in multi radios over fibre performance in terms of application response delay and power consumption by upto 75% and 15 % respectively, reduction in traffic loss by upto 53% and reduction in delay for real time application by more than 25% in some cases