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Classification of labour pain using electroencephalogram signal based on wavelet method / Sai Chong Yeh
Get PDFElectroencephalogram (EEG) is the recording of electrical activity of the cerebral cortex through electrodes placed on the scalp. EEG is used to acquire neurophysiological signals for application in clinical diagnosis and brain computer interface (BCI). However, in practical settings the EEG signals are often contaminated by signal artifacts known as the biological and environmental artifacts. These artifacts degrade EEG signals, thereby obstructing clinical diagnosis or BCI applications by distorting the observed power spectrum. Procedures for automated removal of EEG artifacts are frequently sought after in pre-processing and filtering of the EEG signals.
In recent years, a combination of independent component analysis (ICA) and discrete wavelet transform (DWT) has been introduced as standard technique for EEG artifact removal. However, in performing the wavelet-ICA procedure, visual inspection or arbitrary thresholding may be required to identify the artifactual components in the EEG signal. This study proposed an integrated system for EEG signals pre-processing by using machine learning algorithms in the identification of artifactual components during the process of Wavelet-ICA. Supervised and unsupervised machine learning algorithms particularly the Support Vector Machine (SVM) and Density Based Spatial Clustering of Application with Noise (DBSCAN) are used in this study. These methods present a robust system that enables fully automated identification and removal of artifacts from EEG signals, without the need of visual inspection or arbitrary thresholding. The training and parameters selection of the machine learning algorithms are conducted using EEG data collected from ten subjects in the laboratory. Using test data contaminated by eye blink artifacts and public dataset from EEGLAB, it was shown that these methods performed better in identifying artifactual components than did existing thresholding methods. Furthermore, wavelet-ICA in conjunction with machine learning algorithm successfully removed target artifacts, while largely retaining the EEG source signals of interest. This method is also extendable to accommodate multiple types of artifacts present in multichannel EEG.
As a practical application of this study, the developed system is used in an application to monitor pain response due to uterine contractions during labour. This part of the study aimed to assess the utility of EEG as an objective marker of pain during the first stage of labour. We obtained EEG and cardiotocography (CTG) data in ten parturient women during their first stage of labour. The study subjects reported the extent of their pain experienced due to uterine contractions, which were recorded by the CTG tracing. Simultaneous 16-channels EEG traces were obtained for spectral analysis and a subsequent classification using SVM aiming to predict the pain experienced in relation to uterine contractions. It was found that pain due to uterine contraction correlated positively with relative delta and beta band activities and negatively with relative theta and alpha band activities of the EEG signals. SVM using the spectral activities, statistical and non-linear features classified the state of pain with an accuracy of 83% using a classification model generalizable across subjects. Furthermore, dimension reduction using principal component analysis (PCA) successfully reduced the number of features used in the classification while achieving a maximum classification accuracy of 84%. The results shown that continuous EEG affords the means to assess objectively maternal pain experienced.
All in all, this study aims to design, develop, optimize and test the method of pain assessment using the EEG signal during the active contraction phase of the first stage of labour. Future studies are envisioned to investigate EEG markers of pain in other clinical states, aiming to generalize the use of EEG as an objective method of pain assessment
Synthesis and characterization of porous carbon composite derived from biomass waste for supercapacitor application / Sim Cheng Kim
Get PDFEnergy storage devices have gradually dominated human daily activities and indispensable to economy development such as supercapacitor and battery. There are few factors determining the performance of supercapacitor and active material is one of the crucial. Therefore, biomass such as pineapple peel (PP) and green waste (GW) were preferred and prior mixed with manganese and tin carbonate to synthesize carbon composite (PP/GW-ZMO and PP/GW-ZTO) via combustion. Brunauer–Emmett–Teller (BET) was employed to study the textural properties with the highest specific surface area obtained in PP-C (1765.92 m2g-1) and GW-C (1613.92 m2g-1). The existence of composite materials was examined using x-ray diffraction (XRD), energy-dispersive x-ray spectroscopy (EDX) and transmission electron microscopy (TEM). Field emission scanning electron microscopy (FESEM) results indicated weight ratio of composite materials have altered the morphology structure. Electrochemical studies implied that carbon composite materials derived from GW exhibited better specific capacitance such as GW-ZMO1 and GW-ZTO1 achieved 123 Fg-1 and 104 Fg-1 at 0.3 Ag-1, respectively. Symmetrical cells were fabricated to examine the device’s performance. Stability test implied that devices fabricated from both porous carbon and carbon composites were steady after 5000 cycles at 0.3 Ag-1 with capacitance retention more than 85 %. Nevertheless, PP-C exhibited poor durability which it dropped drastically to almost null specific capacitance while PP-ZMO1, PP-ZTO1, GW-ZMO1 and GW-ZTO1 retained 65 %, 88 %, 79 % and 106 %, accordingly after 900 cycles of varies current densities
Investigation of complex refractive index of graphene oxide using polarisation response of graphene oxide-coated planarized optical waveguide / Gan Soon Xin
Get PDFSince a single atomic layer of carbon, also as known as graphene is being successfully exfoliated from 3D graphite, intense research on graphene and its derivative begins. Among them, graphene oxide (GO) is considered one of the most prominent candidates in the category of graphene derivatives for the application of electronic, optoelectronic and photonics. However, although GO has been applied in many applications like saturable absorbers of Q-switch laser and optical limiters for eye protection, its intrinsic optical properties especially complex refractive index reported so far still has a large deviation. Also, most of the optical characterization research on GO were conducted in the visible wavelength spectrum instead of near infrared (NIR) range. Thus, this thesis aims to determine the anisotropic complex refractive index of graphene oxide (GO) at 1550 nm using optical chip-based device. We propose a planarized optical waveguide structure that facilitates strong polarization dependent light interaction. The light propagation characteristic in thin film coated planarized optical waveguide is firstly studied. Using Finite Element Method (FEM), the optical response of planarized optical waveguide coated with thin film overlays with different refractive indices is obtained. The effective index, neff of optical waveguide increases with larger refractive index of the thin film overlay but decreases when its extinction coefficient is increased. The effective extinction coefficient, keff of the thin film coated increases when both the real and imaginary part of the thin film increases. It is found that TE-mode has stronger interaction with thin film overlay as compared to TM-mode, giving the capability of determining the optical constant of the thin film overlay by cross-referencing the experimental and numerical results. Following the completion of simulation work, experiment measuring the propagation loss-to-coating thickness profile of GO-coated planarized optical waveguide is carried out. GO films with sub-micron thickness (0.1 μm to 1.0 μm) were successfully produced using drop-casting technique. As predicted by simulation, the GO-coated waveguide exhibits large polarization dependent loss which depends strongly on the coating thickness. By cross-referencing the experimental and simulation results, the GO film’s complex refractive indices of 1.66+0.17i and 1.615+0.002i for TE- and TM-polarized light, respectively, are obtained. The uncertainties for the real part of refractive index are 0.03 and 0.020 for TE- and TM-polarized light respectively, whereas the uncertainties for the imaginary part of refractive index are 0.01 and 0.001 for TE- and TM-polarized light, respectively. The results obtained will be valuable in advancing the research and development of GO photonics, especially in the development of optical telecommunication devices where NIR wavelengths are used as information carrier
Development of integrated zinc oxide nanorods coated glass substrate sensing device / Haziezol Helmi Mohd Yusof
Get PDFA simple and practical cost-effective integrated zinc oxide (ZnO) nanorods coated glass substrate sensing device for humidity and formaldehyde vapor sensing applications is reported. The developed sensor device is composed of a commercial light-emitting diode (LED) and photodiode that correspondingly served as light source and detector which precisely positioned on a 3D printed sensor platform. A receiver circuit and Arduino platform were employed for signal amplification and processing. A uniform ZnO nanorods coating were grown on the surface of glass substrate via hydrothermal method by controlling the growth durations and coating length. A standard reference for the optimum working condition of sensing device was presented by maximizing the dynamic range of the fabricated glass substrates towards humidity sensing. The first order of theoretical model was derived in which two new normalized parameters (Z and ζ) were introduced. An experimental validation was performed and showed well correlation towards the theoretical approach. The optimum sensing response of the sensor device was found to be effective by the determination of parameter Z and ζ instead of a specific growth conditions (growth duration and coating length). The fabricated sensor device was successfully characterized towards humidity and formaldehyde vapor concentrations. A significant response towards relative humidity (RH) levels between 35% and 90% was exhibited which the output voltage reduced in non-linear trend by 750 mV with average sensitivity of -12 mV/%. The sensing performance of the sensor device produced an average response time of 3.8 s for relative humidity (RH) level from 35% to 85% and showed quicker recovery time of 2.2 s. The device also demonstrated good response in detecting formaldehyde vapor concentrations with good sensing stability at small change of concentration as low as 1%
An improved bone age assessment using advanced image processing and deep learning approach / Liang Kim Meng
Get PDFPediatricians often apply bone age assessment to measure the skeletal maturity of children and to predict the future height. These discrepancies are good indicators for diagnosing growth disorders. Normally, left hand skeletal is employed in this assessment. The low quality of ossification sites of carpals deteriorates the pediatrician’s visibility in inspecting the pertinent radiographic manifestations. This in turn affects the bone age assessment. Therefore, we have to enhance the quality before assessing them. Histogram equalization is one of the contrast enhancement techniques that suit this type of enhancement. Existing histogram equalizations, however, are confronting with problems in preserving the brightness and details as well as preventing the contrast from being over-enhanced or under-enhanced simultaneously. The comprehensive histogram equalization was proposed by considering all criteria of the desired histogram-equalized image to produce moderately contrast enhanced carpals’ ossification sites. Qualitative results show that the determining features of maturity stages have been emphasized in some of the Pareto optimized image. The improvement for Pareto optimized image by bi-histogram equalization is significant for five stages from stage D to stage H with improvement accuracy of 7.16%, 12.47%, 16.03%, 21.21% and 18.51%, respectively. Findings concluded that the Pareto optimized images able to improve the classifier accuracy that estimate the maturity stage of the carpal bones
The expressive forms of Xu Bing’s Neo English calligraphy / Xie Jinfu
Get PDFXu Bing is active in the contemporary art world and a famous calligraphy artist and painter who held many individual art exhibitions in New York New Art Museum, Czech National Museum and other famous international art institutions. In 1999, he was the recipient of a MacArthur Fellowship in recognition of his "significant contribution to society, particularly in printmaking and calligraphy". Xu Bing created a kind of new square character which combined English alphabets with Chinese calligraphy strokes and named it Neo English calligraphy. A series of Neo English calligraphy artwork was produced which theoretically influenced by the Chinese traditional philosophy and transformed into Chinese calligraphy which makes many experts, scholars and even the general public interested in its "value" and "innovation". This paper focuses on the expressive form of Neo English calligraphy and analyses its social impact
The effects of song singing patterns on the vocal singing achievement among primary level students / Catherine Marie Januarius
Get PDFThe purpose of this study is to investigate the effects of song singing patterns on the vocal achievement skills of Year 3 and Year 4 students in the primary level of music education. The participants for this study comprised of 60 students (n=60) from Year 3 and Year 4 primary levels for this study. Some students have been subjected to prior singing lessons but do not possess a systemised training in interval recognition, expression and stylistic singing and vocal singing techniques. This study employed a control group design compared to treatment group in a pre-test and post-test exercise to measure the vocal achievement skills of young children by investigating the effectiveness of using intervallic singing exercises versus song singing exercises through The Sound of Music excerpts of songs. The treatment administered was 20-minute sessions per week for the duration of eight weeks with the inclusion of additional pre-test and post-tests the week before and after the treatment period. Data was collected and subjected to the critieria of four tests, Intervallic Singing Test (IST), Expression and Stylistic Singing Test (ESST), Singing Tonality Test (STT) and Vocal Singing Technique Test (VSTT). Results showed that children taught through the song singing patterns method performed the songs with significant achievement than did those taught through the intervallic singing process
A multicriteria aware optimal routing approach for enhancing quality of service in device to device communication / Valmik Tilwari
Get PDFAs the world is moving towards the digitalization era, increasing demands of higher data rates, energy effiffifficiency, and seamless connectivity are skyrocketing. Device-to-Device (D2D) communication is one of the key technologies for future Fifth Generation (5G) network. D2D communication technology enhances network coverage, boosts spectral efficiency, has low latency, and enables the devices to communicate with each other, with partial or none involvement of network infrastructure. Therefore, factors of such nature make D2D communication a promising medium guarantying reliability to several telecommunications scenarios. D2D caters to all the needs of it’s users, from the high demand of peer-to-peer users for data transmissions in Ultra-Dense Network (UDN) to building up a network that is resilient against natural disasters. In the orthodox cellular network, all the users are directly connected with a one-hop link to the network infrastructure. In contrast, for the D2D communication, a relay device is needed due to the multi-hop link between source and destination device for data transmission. For this, a routing approach plays a significant role in achieving efficient and reliable data transmission to the end-users. This study proposed three routing approaches in three main D2D communication scenarios. In the conventional D2D communication scenario, the network topology is highly dynamic and changes in an unpredictable manner due to the high displacement of devices in the network. This scenario affected the stability of the network and established routes which significantly degrades the network performance. Therefore, the Mobility, Residual energy, and Link quality Aware Multipath (MRLAM) routing approach is proposed to optimize the network and route stability for the conventional D2D communication scenario. Meanwhile, in the D2D communication UDN scenario, traffic congestion occurs on a single mobile device when there is an excessive flow of packets, and it carries most of the network traffic. This scenario induces data packets transmission end-to-end delay in the network. Therefore, Multipath Battery, Mobility, and Queue length Aware (MBMQA) routing approach is proposed in order to balanced data traffic load among the mobile devices in the D2D communication UDN scenario. Whereas, in the D2D communication-based Disaster Management Scenario (DMS), the mobile devices are equipped with limited energy resources for their vital operation of data transmission. Thus, the connectivity of the devices suffers from packets drops as soon as the device's energy gets exhausted. Similarly, the mobile devices in the network, change their position frequently, which induces the chance of link failure in the established route. Therefore, Energy, Mobility, Backpressure, and Link quality Routing (EMBLR) approach is proposed in the D2D communication based on DMS to balance the energy consumption load among the devices and ensure reliable data transmission. Extensive simulations have been conducted that illustrate that proposed routing approaches significantly enhanced Quality of Service (QoS) network performance metrics for different D2D communication scenarios as compared with other well-known routing approaches. It is evident that the findings presented in the study are useful for designing the routing approach in future D2D communication.
Index terms: 5G network, D2D communication; Internet of things; Routing; Multi criteria decision makin
Anticancer activity of Ficus deltoidea and Tualang honey on oral cancer cells: An in vivo study / May Ameen Saeed Alkoshab
Get PDFThe use of natural products have been gaining interest, notably in the area of cancer therapy
and in this study, natural products rich in antioxidants such as Tualang Honey (Malaysian
wild local honey) and Ficus deltoidea (Malaysian local herbal plant), were selected to assess
their chemo-preventive and chemotherapeutic activities on oral cancer. The aim of this study
is to evaluate the chemo-preventive and chemotherapeutic activities of Ficus deltoidea (FD)
and Tualang Honey (TH) in an animal model induced for oral cancer using 4-Nitroquinoline1-oxide (4NQO). A total of 70 male Sprague-Dawley (SD) rats were distributed into ten
groups (n=7 per group); Group 1, (untreated group), Group 2, (control cancer group) received
4NQO only during 8 weeks in drinking water. Groups 3, 4, 5 and 6 (chemo-preventive)
received 4NQO for 8 weeks and were simultaneously treated with FD extract at 250 and 500
mg/kg and TH at 1000 and 2000 mg/kg respectively by oral gavage. Group 7, 8, 9 and 10
(chemotherapeutic) received 4NQO for 8 weeks followed by the administration of FD extract
at 250 and 500 mg/kg and TH at 1000 and 2000 mg/kg respectively, for another 10 weeks.
All rats from all experiments were sacrificed after 22 weeks, and the histopathological
changes and incidence of oral cancer were microscopically evaluated. An
immunohistochemical evaluation was conducted to determine the effects of the FD extract and
TH on the expression of tumour markers; cyclin D1, bcl2, p53, β- catenin and e-cadherin using
a computerised image analyser system, while the RT2 Profiler PCR Array method was
employed in this study for gene expression analysis of TP53, RAC1, COX-2, TWIST 1, CCND1
and EGFR. The results of the present study showed a beneficial regression effect of the FD
extract and TH on tumour progression, especially in the chemo-preventive groups. The FD
extract and TH significantly reduced the incidence of oral squamous cell carcinoma (OSCC)
iv
from 100% to 14.3% in the high dose groups. The immunohistochemical analysis showed
that the FD extract and TH had significantly decreased the expression of the key tumour
marker cyclin D1 and had significantly increased the expression of the β-catenin and ecadherin proteins that are associated with enhanced cellular adhesion. Based on the gene
expression analysis, TH and FD extract had reduced the expression of the TWIST1 and RAC1
genes associated with epithelial-mesenchymal transition (EMT) and had significantly downregulate the COX-2 and EGFR genes associated with cancer angiogenesis, metastasis and
chemo resistance. In conclusion, our data suggest that the FD extract and TH exert chemopreventive and chemotherapeutic activities in an animal model induced for oral cancer using
4NQO and thus, have the potential to be developed as chemo-preventive and chemotherapeutic
agent
Synthesis and characterization of self-cleaning hydrophobic organic coating / Amirul Syafiq Abdul Jaafar
No full textThree self-cleaning coating systems namely Polydimethylsiloxane (PDMS)/Sylgard, PDMS/3-Aminopropyltriethoxysilane (APTES) (tagged as A1) and A1 blended with nano-Calcium Carbonate (CaCO3) have been synthesised on glass substrates via dip-coating and spray-coating techniques. All of the prepared coatings were dried under ambient condition before being subjected to characterisations and testing(s). The effect of various weight percentages of Sylgard resin that are 5wt.% (S1 coating), 10wt.% (S2 coating), 15wt.% (S3 coating), and 20 wt.% (S4 coating) on the hydrophobicity, self-cleaning property, anti-fog performance and mechanical property of PDMS/Sylgard coating have been discussed in the first section of this thesis. The PDMS/Sylgard coated glass substrates exhibit transmittance above 94% in UV-Vis region, indicating high transparency. From the micro-scratch and micro-hardness tests, it was observed that the PDMS/Sylgard coating possess of stronger adhesion to glass substrate as the Sylgard concentration increased suggesting that the surface became stiffer with greater Sylgard concentration in PDMS matrix. The Water Contact Angle (WCA) showed that hydrophobicity of PDMS/Sylgard coated glass increased with increasing weight percentage of Sylgard up to 10 wt. %. When the weight percentage was above 15 wt. %, the WCA started to decrease due to saturated Si-O-Si crosslinking. In addition, the S2 coating showed an excellent anti-fog performance and great self-cleaning behavior where its transparency was above 64% after exposed to outdoor environment for 4 months. Thereafter, the best composition of S2 resin (10 wt.% Sylgard) was blended with the APTES ( A1 matrix) and different weight ratios of nano-Calcium Carbonate (CaCO3) that are 0.2wt.% (C1 coating), 0.4wt.% (C2 coating), 0.6wt.% (C3 coating), 0.8wt.% (C4 coating), 1.0wt.% (C5 coating) and 1.2wt.% (C6 coating) that have been discussed in the second section of this work. Both A1 coating and A1 blended with nano-CaCO3 coating systems exhibit high transmission above 83% in UV-VIS region. The consolidation of nano-CaCO3 in A1 matrix significantly improved the WCA of coating system since embedded nano-CaCO3 intensifies A1 surface roughness. The hydrophobicity of A1 blended with nano-CaCO3 coating systems increases with increasing of wt. % of nano-CaCO3 up to 0.8 wt. %. As the weight percentages was increased above 0.8wt%, WCA of A1/nano-CaCO3 coating system reduces to lower value due to agglomerations of nanoparticles at high nano-CaCO3 loading rates. The A1 blended with nano-CaCO3 coating systems exhibit stronger adhesion to glass substrate as weight percentages of nano-CaCO3 increased up to 0.8 wt.%. However, the A1 blended with nano-CaCO3 coating systems displayed weaker adhesion at high loading rates of nano-CaCO3 mainly above 0.8wt.% because higher loading rates of nanoparticles in A1 matrix lead to more crystalline surface and more crystalline surface make the surface become more brittle. Due to high hydrophobicity, the C4 coating exhibit the best anti-fog performance and achieves great self-cleaning effect among A1 blended with nano-CaCO3 coating systems under outdoor environment where its transparency was above 74% after exposed to outdoor environment for 4 months. Overall, all three coating systems retained their hydrophobicity after prolonged outdoor environment, revealed that prepared coatings systems have strong durability against rainfall impact.