1,691 research outputs found
Postural injury risk assessment for industrial processes using advanced sensory systems
The major contributions of this research delivered both advancements and novel frameworks to enhance the current methods of postural assessments within industrial environments. This included the development of load vs repetition analysis, A novel BVH Model and a low cost ergonomic scoring tool relying on pixel labelling
Application of Deep Neural Network in Healthcare data
Biomedical data analysis has been playing an important role in healthcare provision services. For decades, medical practitioners and researchers have been extracting and analyse biomedical data to derive different health-related information. Recently, there has been a significant rise in the amount of biomedical data collection. This is due to the availability of biomedical devices for the extraction of biomedical data which are more portable, easy to use and affordable, as an effect technology advancement. As the amount of biomedical data produced every day increases, the risk of human making analytical and diagnostic mistakes also increases. For example, there are approximately 40 million diagnostic errors involving medical imaging annually worldwide, hence rise a need for the development of fast, accurate, reliable and automatic means for analysis of biomedical data. Conventional machine learning has been used to assist in the analysis and interpretation of biomedical data automatically, but always limited with the need for feature extraction process to train the built models. To achieve this, three studies have been conducted. Two studies were conducted by using EEG signals and one study by using microscopic images of cancer cells. In the first study with EEG signals, our method managed to interpret motor imaginary activities from a 64 channels EEG device with 99% classification accuracy when all the 64 channels were used and 91.5% classification when the number of channels was selected to eight (8) channels. In a second study which involved steady-state visual evoked potential form of EEG signals, our method achieved an average of 94% classification accuracy by using two channels, skin like EEG sensor. In the third study for authentication of cancer cell lines by using microscopic images, our method managed to attain an average of 0.91 F1-score in the authentication of eight classes of cancer cell lines. Studies reported in this thesis, significantly shows that CNN can play a major role in the development of a computerised way in the analysis of biomedical data. Towards provision of better healthcare by using CNN in analysis of different formats of biomedical data, this thesis has three major contributions, i) introduction of a new method for EEG channels selection towards development of portable EEG sensors for real-life application, and ii) introduction of a method for cancer cell lines authentication in the laboratory environment towards development of anti-cancer drugs, and iii) Introduction of a method for authentication of isogenic cancer cell lines
Non-Contact Sleep Monitoring
"The road ahead for preventive medicine seems clear. It is the delivery
of high quality, personalised (as opposed to depersonalised) comprehensive
medical care to all." Burney, Steiger, and Georges (1964)
This world's population is ageing, and this is set to intensify over the next forty years.
This demographic shift will result in signicant economic and societal burdens (partic-
ularly on healthcare systems). The instantiation of a proactive, preventative approach
to delivering healthcare is long recognised, yet is still proving challenging. Recent work
has focussed on enabling older adults to age in place in their own homes. This may
be realised through the recent technological advancements of aordable healthcare sen-
sors and systems which continuously support independent living, particularly through
longitudinally monitoring deviations in behavioural and health metrics. Overall health
status is contingent on multiple factors including, but not limited to, physical health,
mental health, and social and emotional wellbeing; sleep is implicitly linked to each of
these factors.
This thesis focusses on the investigation and development of an unobtrusive sleep mon-
itoring system, particularly suited towards long-term placement in the homes of older
adults. The Under Mattress Bed Sensor (UMBS) is an unobstrusive, pressure sensing
grid designed to infer bed times and bed exits, and also for the detection of development
of bedsores. This work extends the capacity of this sensor. Specically, the novel contri-
butions contained within this thesis focus on an in-depth review of the state-of-the-art
advances in sleep monitoring, and the development and validation of algorithms which
extract and quantify UMBS-derived sleep metrics.
Preliminary experimental and community deployments investigated the suitability of the
sensor for long-term monitoring. Rigorous experimental development rened algorithms
which extract respiration rate as well as motion metrics which outperform traditional
forms of ambulatory sleep monitoring. Spatial, temporal, statistical and spatiotemporal
features were derived from UMBS data as a means of describing movement during sleep.
These features were compared across experimental, domestic and clinical data sets, and
across multiple sleeping episodes. Lastly, the optimal classier (built using a combina-
tion of the UMBS-derived features) was shown to infer sleep/wake state accurately and
reliably across both younger and older cohorts.
Through long-term deployment, it is envisaged that the UMBS-derived features (in-
cluding spatial, temporal, statistical and spatiotemporal features, respiration rate, and
sleep/wake state) may be used to provide unobtrusive, continuous insights into over-
all health status, the progression of the symptoms of chronic conditions, and allow the
objective measurement of daily (sleep/wake) patterns and routines
Information technologies for pain management
Millions of people around the world suffer from pain, acute or chronic and this raises the
importance of its screening, assessment and treatment. The importance of pain is attested by
the fact that it is considered the fifth vital sign for indicating basic bodily functions, health
and quality of life, together with the four other vital signs: blood pressure, body
temperature, pulse rate and respiratory rate. However, while these four signals represent an
objective physical parameter, the occurrence of pain expresses an emotional status that
happens inside the mind of each individual and therefore, is highly subjective that makes
difficult its management and evaluation. For this reason, the self-report of pain is considered
the most accurate pain assessment method wherein patients should be asked to periodically
rate their pain severity and related symptoms. Thus, in the last years computerised systems
based on mobile and web technologies are becoming increasingly used to enable patients to
report their pain which lead to the development of electronic pain diaries (ED). This approach
may provide to health care professionals (HCP) and patients the ability to interact with the
system anywhere and at anytime thoroughly changes the coordinates of time and place and
offers invaluable opportunities to the healthcare delivery. However, most of these systems
were designed to interact directly to patients without presence of a healthcare professional
or without evidence of reliability and accuracy. In fact, the observation of the existing
systems revealed lack of integration with mobile devices, limited use of web-based interfaces
and reduced interaction with patients in terms of obtaining and viewing information. In
addition, the reliability and accuracy of computerised systems for pain management are
rarely proved or their effects on HCP and patients outcomes remain understudied.
This thesis is focused on technology for pain management and aims to propose a monitoring
system which includes ubiquitous interfaces specifically oriented to either patients or HCP
using mobile devices and Internet so as to allow decisions based on the knowledge obtained
from the analysis of the collected data. With the interoperability and cloud computing
technologies in mind this system uses web services (WS) to manage data which are stored in a
Personal Health Record (PHR).
A Randomised Controlled Trial (RCT) was implemented so as to determine the effectiveness
of the proposed computerised monitoring system. The six weeks RCT evidenced the
advantages provided by the ubiquitous access to HCP and patients so as to they were able to
interact with the system anywhere and at anytime using WS to send and receive data. In
addition, the collected data were stored in a PHR which offers integrity and security as well
as permanent on line accessibility to both patients and HCP. The study evidenced not only
that the majority of participants recommend the system, but also that they recognize it
suitability for pain management without the requirement of advanced skills or experienced users. Furthermore, the system enabled the definition and management of patient-oriented
treatments with reduced therapist time. The study also revealed that the guidance of HCP at
the beginning of the monitoring is crucial to patients' satisfaction and experience stemming
from the usage of the system as evidenced by the high correlation between the
recommendation of the application, and it suitability to improve pain management and to
provide medical information. There were no significant differences regarding to
improvements in the quality of pain treatment between intervention group and control group.
Based on the data collected during the RCT a clinical decision support system (CDSS) was
developed so as to offer capabilities of tailored alarms, reports, and clinical guidance. This
CDSS, called Patient Oriented Method of Pain Evaluation System (POMPES), is based on the
combination of several statistical models (one-way ANOVA, Kruskal-Wallis and Tukey-Kramer)
with an imputation model based on linear regression. This system resulted in fully accuracy
related to decisions suggested by the system compared with the medical diagnosis, and
therefore, revealed it suitability to manage the pain. At last, based on the aerospace systems
capability to deal with different complex data sources with varied complexities and
accuracies, an innovative model was proposed. This model is characterized by a qualitative
analysis stemming from the data fusion method combined with a quantitative model based on
the comparison of the standard deviation together with the values of mathematical
expectations. This model aimed to compare the effects of technological and pen-and-paper
systems when applied to different dimension of pain, such as: pain intensity, anxiety,
catastrophizing, depression, disability and interference. It was observed that pen-and-paper
and technology produced equivalent effects in anxiety, depression, interference and pain
intensity. On the contrary, technology evidenced favourable effects in terms of
catastrophizing and disability. The proposed method revealed to be suitable, intelligible, easy
to implement and low time and resources consuming. Further work is needed to evaluate the
proposed system to follow up participants for longer periods of time which includes a
complementary RCT encompassing patients with chronic pain symptoms. Finally, additional
studies should be addressed to determine the economic effects not only to patients but also
to the healthcare system
A Large-Scale Study of a Sleep Tracking and Improving Device with Closed-loop and Personalized Real-time Acoustic Stimulation
Various intervention therapies ranging from pharmaceutical to hi-tech
tailored solutions have been available to treat difficulty in falling asleep
commonly caused by insomnia in modern life. However, current techniques largely
remain ill-suited, ineffective, and unreliable due to their lack of precise
real-time sleep tracking, in-time feedback on the therapies, an ability to keep
people asleep during the night, and a large-scale effectiveness evaluation.
Here, we introduce a novel sleep aid system, called Earable, that can
continuously sense multiple head-based physiological signals and simultaneously
enable closed-loop auditory stimulation to entrain brain activities in time for
effective sleep promotion. We develop the system in a lightweight, comfortable,
and user-friendly headband with a comprehensive set of algorithms and dedicated
own-designed audio stimuli. We conducted multiple protocols from 883 sleep
studies on 377 subjects (241 women, 119 men) wearing either a gold-standard
device (PSG), Earable, or both concurrently. We demonstrate that our system
achieves (1) a strong correlation (0.89 +/- 0.03) between the physiological
signals acquired by Earable and those from the gold-standard PSG, (2) an 87.8
+/- 5.3% agreement on sleep scoring using our automatic real-time sleep staging
algorithm with the consensus scored by three sleep technicians, and (3) a
successful non-pharmacological stimulation alternative to effectively shorten
the duration of sleep falling by 24.1 +/- 0.1 minutes. These results show that
the efficacy of Earable exceeds existing techniques in intentions to promote
fast falling asleep, track sleep state accurately, and achieve high social
acceptance for real-time closed-loop personalized neuromodulation-based home
sleep care.Comment: 33 pages, 8 figure
Digital Twin of Cardiovascular Systems
Patient specific modelling using numerical methods is widely used in understanding diseases and disorders. It produces medical analysis based on the current state of patient’s health. Concurrently, as a parallel development, emerging data driven Artificial Intelligence (AI) has accelerated patient care. It provides medical analysis using algorithms that rely upon knowledge from larger human population data. AI systems are also known to have the capacity to provide a prognosis with overallaccuracy levels that are better than those provided by trained professionals. When these two independent and robust methods are combined, the concept of human digital twins arise. A Digital Twin is a digital replica of any given system or process. They combine knowledge from general data with subject oriented knowledge for past, current and future analyses and predictions. Assumptions made during numerical modelling are compensated using knowledge from general data. For humans, they can provide an accurate current diagnosis as well as possible future outcomes. This allows forprecautions to be taken so as to avoid further degradation of patient’s health.In this thesis, we explore primary forms of human digital twins for the cardiovascular system, that are capable of replicating various aspects of the cardiovascular system using different types of data. Since different types of medical data are available, such as images, videos and waveforms, and the kinds of analysis required may be offline or online in nature, digital twin systems should be uniquely designed to capture each type of data for different kinds of analysis. Therefore, passive, active and semi-active digital twins, as the three primary forms of digital twins, for different kinds of applications are proposed in this thesis. By the virtue of applications and the kind of data involved ineach of these applications, the performance and importance of human digital twins for the cardiovascular system are demonstrated. The idea behind these twins is to allow for the application of the digital twin concept for online analysis, offline analysis or a combination of the two in healthcare. In active digital twins active data, such as signals, is analysed online in real-time; in semi-active digital twin some of the components being analysed are active but the analysis itself is carried out offline; and finally, passive digital twins perform offline analysis of data that involves no active component.For passive digital twin, an automatic workflow to calculate Fractional Flow Reserve (FFR) is proposed and tested on a cohort of 25 patients with acceptable results. For semi-active digital twin, detection of carotid stenosis and its severity using face videos is proposed and tested with satisfactory results from one carotid stenosis patient and a small cohort of healthy adults. Finally, for the active digital twin, an enabling model is proposed using inverse analysis and its application in the detection of Abdominal Aortic Aneurysm (AAA) and its severity, with the help of a virtual patient database. This enabling model detected artificially generated AAA with an accuracy as high as 99.91% and classified its severity with acceptable accuracy of 97.79%. Further, for active digital twin, a truly active model is proposed for continuous cardiovascular state monitoring. It is tested on a small cohort of five patients from a publicly available database for three 10-minute periods, wherein this model satisfactorily replicated and forecasted patients’ cardiovascular state. In addition to the three forms of human digital twins for the cardiovascular system, an additional work on patient prioritisation in pneumonia patients for ITU care using data-driven digital twin is also proposed. The severity indices calculated by these models are assessed using the standard benchmark of Area Under Receiving Operating Characteristic Curve (AUROC). The results indicate that using these models, the ITU and mechanical ventilation can be prioritised correctly to an AUROC value as high as 0.89
On Deep Machine Learning Methods for Anomaly Detection within Computer Vision
This thesis concerns deep learning approaches for anomaly detection in images. Anomaly detection addresses how to find any kind of pattern that differs from the regularities found in normal data and is receiving increasingly more attention in deep learning research. This is due in part to its wide set of potential applications ranging from automated CCTV surveillance to quality control across a range of industries. We introduce three original methods for anomaly detection applicable to two specific deployment scenarios. In the first, we detect anomalous activity in potentially crowded scenes through imagery captured via CCTV or other video recording devices. In the second, we segment defects in textures and demonstrate use cases representative of automated quality inspection on industrial production lines. In the context of detecting anomalous activity in scenes, we take an existing state-of-the-art method and introduce several enhancements including the use of a region proposal network for region extraction and a more information-preserving feature preprocessing strategy. This results in a simpler method that is significantly faster and suitable for real-time application. In addition, the increased efficiency facilitates building higher-dimensional models capable of improved anomaly detection performance, which we demonstrate on the pedestrian-based UCSD Ped2 dataset. In the context of texture defect detection, we introduce a method based on the idea of texture restoration that surpasses all state-of-the-art methods on the texture classes of the challenging MVTecAD dataset. In the same context, we additionally introduce a method that utilises transformer networks for future pixel and feature prediction. This novel method is able to perform competitive anomaly detection on most of the challenging MVTecAD dataset texture classes and illustrates both the promise and limitations of state-of-the-art deep learning transformers for the task of texture anomaly detection
Severity scoring approach using modified optical flow method and lesion identification for facial nerve paralysis assessment
The facial nerve controls facial movement and expression. Hence, a patient with facial nerve paralysis will experience affected social interactions, psychological distress, and low self-esteem. Upon the first presentation, it is crucial to determine the severity level of the paralysis and take out the possibility of stroke or any other serious causes by recognising the type of lesion in preventing any mistreatment of the patient. Clinically, the facial nerve is assessed subjectively by observing voluntary facial movement and assigning a score based on the deductions made by the clinician. However, the results are not uniform among different examiners evaluating the same patients. This is extremely undesirable for both medical diagnostic and treatment considerations. Acknowledging the importance of this assessment, this research was conducted to develop a facial nerve assessment that can classify both the severity level of facial nerve function and also the types of facial lesion, Upper Motor Neuron (UMN) and Lower Motor Neuron (LMN), in facial regional assessment and lesion assessment, respectively. For regional assessment, two optical flow techniques, Kanade-Lucas-Tomasi (KLT) and Horn-Schunck (HS) were used in this study to determine the local and global motion information of facial features. Nevertheless, there is a problem with the original KLT which is the inability of the Eigen features to distinguish the normal and patient subjects. Thus, the KLT method was modified by introducing polygonal measurements and the landmarks were placed on each facial region. Similar to the HS method, the multiple frames evaluation was proposed rather than a single frame evaluation of the original HS method to avoid the differences between frames becoming too small. The features of these modified methods, Modified Local Sparse (MLS) and Modified Global Dense (MGD), were combined, namely the Combined Modified Local-Global (CMLG), to discover both local (certain region) and global (entire image) flow features. This served as the input into the k-NN classifier to assess the performance of each of them in determining the severity level of paralysis. For the lesion assessment, the Gabor filter method was used to extract the wrinkle forehead features. Thereafter, the Gabor features combined with the previous features of CMLG, by focusing only on the forehead region to evaluate both the wrinkle and motion information of the facial features. This is because, in an LMN lesion, the patient will not be able to move the forehead symmetrically during the rising eyebrows movement and unable to wrinkle the forehead due to the damaged frontalis muscle. However, the patient with a UMN lesion exhibits the same criteria as a normal subject, where the forehead is spared and can be lifted symmetrically. The CMLG technique in regional assessment showed the best performance in distinguishing between patient and normal subjects with an accuracy of 92.26% compared to that of MLS and MGD, which were 88.38% and 90.32%, respectively. From the results, some assessment tools were developed in this study namely individual score, total score and paralysis score chart which were correlated with the House-Brackmann score and validated by a medical professional with 91.30% of accuracy. In lesion assessment, the combined features of Gabor and CMLG on the forehead region depicted a greater performance in distinguishing the UMN and LMN lesion of the patient with an accuracy of 89.03% compared to Gabor alone, which was 78.07%. In conclusion, the proposed facial nerve assessment approach consisting of both regional assessment and lesion assessment is capable of determining the level of facial paralysis severity and recognising the type of facial lesion, whether it is a UMN or LMN lesion
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