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Articles 1 - 30 of 118

Full-Text Articles in Biomedical Engineering and Bioengineering

الگو و دستورالعمل تهيه و تدوين پايان نامه کارشناسي ارشد, Dr Alireza Zolfaghari Oct 2015

الگو و دستورالعمل تهيه و تدوين پايان نامه کارشناسي ارشد, Dr Alireza Zolfaghari

Dr Alireza Zolfaghari

No abstract provided.


Biosensing Enhancement Of Dengue Virus Using Microballoon Mixers On Centrifugal Microfluidic Platforms May 2015

Biosensing Enhancement Of Dengue Virus Using Microballoon Mixers On Centrifugal Microfluidic Platforms

Faculty of Engineering University of Malaya

Dengue is the current leading cause of death among children in several Latin American and Asian countries. Due to poverty in areas where the disease is prevalent and the high cost of conventional diagnostic systems, low cost devices are needed to reduce the burden caused by dengue infection. Centrifugal microfluidic platforms are an alternative solution to reduce costs and increase the availability of a rapid diagnostic system. The rate of chemical reactions in such devices often depends on the efficiency of the mixing techniques employed in their microfluidic networks. This paper introduces a micromixer that operates by the expansion and ...


Effect Of Ion Concentration On Mechanosynthesis Of Carbonated Chlorapatite Nanopowders May 2015

Effect Of Ion Concentration On Mechanosynthesis Of Carbonated Chlorapatite Nanopowders

Faculty of Engineering University of Malaya

Carbonated chlorapatite nanopowders (n-CCAp) with different degrees of substitution were successfully synthesized by the one-step mechanochemical process. Results demonstrated that the formation of n-CCAp was influenced strongly by the carbonate content (x). From X-ray analysis, crystallite size, crystallinity degree, and unit cell volume of n-CCAp decreased significantly as carbonate content (x) increased from 0 to 2. Conversely, the lattice strain and the volume fraction of grain boundaries grew considerably. Microscopic analysis showed the average particle size of the synthesized powders was 15 +/- 10 nm. The influence of carbonate concentration on mechanosynthesis of pure n-CCAp utilizing a facile solid-state process has ...


Classification Of Electrocardiogram And Auscultatory Blood Pressure Signals Using Machine Learning Models May 2015

Classification Of Electrocardiogram And Auscultatory Blood Pressure Signals Using Machine Learning Models

Faculty of Engineering University of Malaya

In this paper, two real-world medical classification problems using electrocardiogram (ECG) and auscultatory blood pressure (Korotkoff) signals are examined. A total of nine machine learning models are applied to perform classification of the medical data sets. A number of useful performance metrics which include accuracy, sensitivity, specificity, as well as the area under the receiver operating characteristic curve are computed. In addition to the original data sets, noisy data sets are generated to evaluate the robustness of the classifiers against noise. The 10-fold cross validation method is used to compute the performance statistics, in order to ensure statistically reliable results ...


Living Wall (Vertical Greening): Benefits And Threats, Mehdi Rakhshandehroo, Mohd Johari Mohd Yusof, Roozbeh Arabi May 2015

Living Wall (Vertical Greening): Benefits And Threats, Mehdi Rakhshandehroo, Mohd Johari Mohd Yusof, Roozbeh Arabi

mrakhshandehroo@yahoo.com

Sustainable development demands a significant approach between architecture and the environment. During the challenge of climate change, energy crisis and urban expansion, a new approach is required to address environmental problems and one of these approaches is vertical greening that can be categorized into green facade and living wall. Living wall systems (LWS) consist of plants and partly growing materials that have a number of beneficial functions, for example: increasing the outdoor and indoor comfort, ecological value, biodiversity, insulation properties, improvement of air quality mitigation of the urban heat island phenomenon, and psychological and social well-being of citizens. This paper ...


Green Façade (Vertical Greening): Benefits And Threats, Mehdi Rakhshandehroo, Mohd Johari Mohd Yusof, Meysam Deghati Najd May 2015

Green Façade (Vertical Greening): Benefits And Threats, Mehdi Rakhshandehroo, Mohd Johari Mohd Yusof, Meysam Deghati Najd

mrakhshandehroo@yahoo.com

In the challenge of development in dense urban areas and environmental preservation, sustainability is a significant requirement where green facade (vertical greening) is one of those approaches that flourished during the last decade although it is not a new concept. Hanging or vertical garden, vertical vegetable farms, balcony garden, container or planter box greening, green or eco building, green roof or rooftop garden, wall planter, and green envelop are all different aspects of this idea that demonstrate how wide this landscape can be. Greening the building envelope with vegetation can be used as a mean to restore the environmental conditions ...


Prediction Of Speech Intelligibility Using A Neurogram Orthogonal Polynomial Measure (Nopm) Apr 2015

Prediction Of Speech Intelligibility Using A Neurogram Orthogonal Polynomial Measure (Nopm)

Faculty of Engineering University of Malaya

Sensorineural hearing loss (SNHL) is an increasingly prevalent condition, resulting from damage to the inner ear and causing a reduction in speech intelligibility. This paper proposes a new speech intelligibility prediction metric, the neurogram orthogonal polynomial measure (NOPM). This metric applies orthogonal moments to the auditory neurogram to predict speech intelligibility for listeners with and without hearing loss. The model simulates the responses of auditory-nerve fibers to speech signals under quiet and noisy conditions. Neurograms were created using a physiologically based computational model of the auditory periphery. A well-known orthogonal polynomial measure, Krawtchouk moments, was applied to extract features from ...


Tribological Investigation Of Ultra-High Molecular Weight Polyethylene Against Advanced Ceramic Surfaces In Total Hip Joint Replacement Apr 2015

Tribological Investigation Of Ultra-High Molecular Weight Polyethylene Against Advanced Ceramic Surfaces In Total Hip Joint Replacement

Faculty of Engineering University of Malaya

The aim of the study was to investigate whether a modified ceramic head surface could reduce the friction and wear rate of simulated ceramic-on-polyethylene hip joints. To address this aim, ultra-high molecular weight polyethylene (UHMWPE) was made to slide on aluminium oxide (Al2O3), dimpled Al2O3, diamond-like carbon (DLC) coated and DLC-coated dimpled substrates. The experiment condition was replicated to simulate artificial hip joints in terms of contact pressure, speed and temperature. UHMWPE on non-dimpled Al2O3 showed lower friction coefficient and wear rate compared to other advanced surfaces. Lower wettability, and higher hardness and surface adhesion of DLC resulted in increased ...


Effect Of High-Energy Ball Milling On The Formation And Micro Structural Features Of Carbonated Chlorapatite Nanopowders Apr 2015

Effect Of High-Energy Ball Milling On The Formation And Micro Structural Features Of Carbonated Chlorapatite Nanopowders

Faculty of Engineering University of Malaya

Carbonated chlorapatite nanopowders (n-CCAp) were synthesized by mechanochemical process from calcite (CaCO3), phosphorus pentoxide (P2O5), and calcium chloride (CaCl2) as raw materials. Results demonstrated that the formation of n-CCAp was influenced strongly by the milling time. At the beginning of milling (up to 15 min), CaCO3 and CaCl2 were the dominant phases, while P2O5 disappeared entirely due to its very high deliquescent nature. With increasing the milling time to 600 min, the progressive mechanochemical reaction was completed which resulted in the formation of nanostructured carbonated chlorapatite. According to the X-ray diffraction data, crystallite size of the product decreased from 24 ...


Fabrication And Characterization Of Poly(Octanediol Citrate)/Gallium-Containing Bioglass Microcomposite Scaffolds Mar 2015

Fabrication And Characterization Of Poly(Octanediol Citrate)/Gallium-Containing Bioglass Microcomposite Scaffolds

Faculty of Engineering University of Malaya

Bone can be affected by osteosarcomae requiring surgical excision of the tumor as part of the treatment regime. Complete removal of cancerous cells is difficult and conventionally requires the removal of a margin of safety around the tumor to offer improved patient prognosis. This work considers a novel series of composite scaffolds based on poly(octanediol citrate) (POC) impregnated with gallium-based bioglass microparticles for possible incorporation into bone following tumor removal. The objective of this research was to fabricate and characterize these scaffolds and subsequently report on their mechanical and biological properties. The porous microcomposite scaffolds with various concentrations of ...


A Glass Polyalkenoate Cement Carrier For Bone Morphogenetic Proteins Mar 2015

A Glass Polyalkenoate Cement Carrier For Bone Morphogenetic Proteins

Faculty of Engineering University of Malaya

This work considers a glass polyalkenoate cement (GPC)-based carrier for the effective delivery of bone morphogenetic proteins (BMPs) at an implantation site. A 0.12 CaO-0.04 SrO-0.36 ZnO-0.48 SiO2 based glass and poly(acrylic acid) (PAA, Mw 213,000) were employed for the fabrication of the GPC. The media used for the water source in the GPC reaction was altered to produce a series of GPCs. The GPC liquid media was either 100 % distilled water with additions of albumin at 0, 2, 5 and 8 wt% of the glass content, 100 % formulation buffer (IFB), and 100 ...


Development Of Novel Passive Check Valves For The Microfluidic Cd Platform Feb 2015

Development Of Novel Passive Check Valves For The Microfluidic Cd Platform

Faculty of Engineering University of Malaya

Microfluidic CD platforms are utilized to perform different biological processes and chemical analyses. In general, a microfluidic CD implements the centrifugal force that is created by the spinning of the platform to pump liquid through the microfluidic network of chambers and channels. Over the last few decades, a wide range of active and passive valving methods were proposed and tested on various microfluidic platforms. Most of the presented valves are too complex to design and involve lengthy fabrication processes. In this paper, easy to fabricate air and liquid check valves for centrifugal microfluidic platforms are presented: a Terminal Check Valve ...


Probabilistic Ensemble Fuzzy Artmap Optimization Using Hierarchical Parallel Genetic Algorithms Feb 2015

Probabilistic Ensemble Fuzzy Artmap Optimization Using Hierarchical Parallel Genetic Algorithms

Faculty of Engineering University of Malaya

In this study, a comprehensive methodology for overcoming the design problem of the Fuzzy ARTMAP neural network is proposed. The issues addressed are the sequence of training data for supervised learning and optimum parameter tuning for parameters such as baseline vigilance. A genetic algorithm search heuristic was chosen to solve this multi-objective optimization problem. To further augment the ARTMAP's pattern classification ability, multiple ARTMAPs were optimized via genetic algorithm and assembled into a classifier ensemble. An optimal ensemble was realized by the inter-classifier diversity of its constituents. This was achieved by mitigating convergence in the genetic algorithms by employing ...


Ultrasound-Based Tissue Characterization And Classification Of Fatty Liver Disease: A Screening And Diagnostic Paradigm Feb 2015

Ultrasound-Based Tissue Characterization And Classification Of Fatty Liver Disease: A Screening And Diagnostic Paradigm

Faculty of Engineering University of Malaya

Fatty Liver Disease (FLD) is a progressively prevalent disease that is present in about 15% of the world population. Normally benign and reversible if detected at an early stage, FLD, if left undetected and untreated, can progress to an irreversible advanced liver disease, such as fibrosis, cirrhosis, liver cancer and liver failure, which can cause death. Ultrasound (US) is the most widely used modality to detect FLD. However, the accuracy of US-based diagnosis depends on both the training and expertise of the radiologist. US-based Computer Aided Diagnosis (CAD) techniques for FLD detection can improve accuracy, speed and objectiveness of the ...


Activation And Inhibition Of Retinal Ganglion Cells In Response To Epiretinal Electrical Stimulation: A Computational Modelling Study Feb 2015

Activation And Inhibition Of Retinal Ganglion Cells In Response To Epiretinal Electrical Stimulation: A Computational Modelling Study

Faculty of Engineering University of Malaya

Objective. Retinal prosthetic devices aim to restore sight in visually impaired people by means of electrical stimulation of surviving retinal ganglion cells (RGCs). This modelling study aims to demonstrate that RGC inhibition caused by high-intensity cathodic pulses greatly influences their responses to epiretinal electrical stimulation and to investigate the impact of this inhibition on spatial activation profiles as well as their implications for retinal prosthetic device design. Another aim is to take advantage of this inhibition to reduce axonal activation in the nerve fibre layer. Approach. A three-dimensional finite-element model of epiretinal electrical stimulation was utilized to obtain RGC activation ...


Advances In Smartphone-Based Point-Of-Care Diagnostics Feb 2015

Advances In Smartphone-Based Point-Of-Care Diagnostics

Faculty of Engineering University of Malaya

Point-of-care (POC) diagnostics is playing an increasingly important role in public health, environmental monitoring, and food safety analysis. Smartphones, alone or in conjunction with add-on devices, have shown great capability of data collection, analysis, display, and transmission, making them popular in POC diagnostics. In this article, the state-of-the-art advances in smartphone-based POC diagnostic technologies and their applications in the past few years are outlined, ranging from in vivo tests that use smartphone's built-in/external sensors to detect biological signals to in vitro tests that involves complicated biochemical reactions. Novel techniques are illustrated by a number of attractive examples, followed ...


Processing And Analysis Of Chitosan Nanocomposites Reinforced With Chitin Whiskers And Tannic Acid As A Crosslinker Jan 2015

Processing And Analysis Of Chitosan Nanocomposites Reinforced With Chitin Whiskers And Tannic Acid As A Crosslinker

Faculty of Engineering University of Malaya

Chitosan film reinforced with nano-sized chitin whiskers and crosslinked using tannic acid was synthesized by the casting-vaporation method. The mechanical and physicochemical properties of several film samples (consisting of different ratio of chitin and tannic acid) were compared with neat chitosan. Tensile tests show that the addition of chitin improves the nanocomposite films mechanical properties up to 137% compared to neat chitosan, but this is slightly degraded when tannic acid is introduced. However, tannic acid and chitin whisker content greatly reduced moisture content by 294% and water solubility by 13%. Transmission electron microscopy (TEM) and Fourier-transform-infrared spectroscopy (FTIR) were used ...


Synthesis Of Well-Crystalline Lattice Carbon Nanotubes Via Neutralized Cooling Method Jan 2015

Synthesis Of Well-Crystalline Lattice Carbon Nanotubes Via Neutralized Cooling Method

Faculty of Engineering University of Malaya

In this contribution, vertically aligned carbon nanotubes were synthesized by chemical vapor deposition (CVD). The effects of intrinsic disorders constructed by mobile surface contaminants on the structural perfection of carbon nanotubes (CNTs) were investigated. The results indicated a complete picture on the effect of the involved parameters on the lattice defects of modulated CNTs based on the cooling step. Raman scattering showed that the different cooling methods of the CVD preforms altered the bound complex defects of the structure of the CNTs. Moreover, an array of CNTs was removed from the silicon substrate by applying the neutralized cooling method on ...


Guided Routing On Spinning Microfluidic Platforms Jan 2015

Guided Routing On Spinning Microfluidic Platforms

Faculty of Engineering University of Malaya

Flow directionality, valving and liquid routing in centrifugal microfluidics (Lab-on-CD) are typically controlled by applying centrifugal and Coriolis forces and have been the subject of active research interest in recent years. Determining and switching the flow direction at a T-junction is a common fluidic operation important for implementing several chemical and clinical assays for Lab-on-CDs. The present work describes a novel approach to route samples and control flow direction on a spinning disc that employs a guiding microstructure that relies on a two-stage valve comprised of an auxiliary inlet, which is a recess embedded at a T-junction, and a bent ...


Improved Friction And Wear Performance Of Micro Dimpled Ceramic-On-Ceramic Interface For Hip Joint Arthroplasty Jan 2015

Improved Friction And Wear Performance Of Micro Dimpled Ceramic-On-Ceramic Interface For Hip Joint Arthroplasty

Faculty of Engineering University of Malaya

The purpose of this study is to investigate the tribological effect of micro-dimpled surface textures for application in ceramic-on-ceramic hip prostheses. A rectangular array of circular dimples was selected as the texture pattern. A CNC micro drilling machine was used to fabricate these dimples on a flat ceramic substrate. Tribology tests were performed by using a pin-on-disk method with selected hertzian contact pressures and speeds based on normal gait of a hip joint, and results compared with non-dimpled surface. A dimpled surface with large dimple diameters and a high dimple density (phi 400 mu m and density 15%) showed significant ...


Interface Stress In Socket/Residual Limb With Transtibial Prosthetic Suspension Systems During Locomotion On Slopes And Stairs Jan 2015

Interface Stress In Socket/Residual Limb With Transtibial Prosthetic Suspension Systems During Locomotion On Slopes And Stairs

Faculty of Engineering University of Malaya

OBJECTIVE: This study aimed to compare the effects of different suspension methods on the interface stress inside the prosthetic sockets of transtibial amputees when negotiating ramps and stairs. DESIGN: Three transtibial prostheses, with a pin/lock system, a Seal-In system, and a magnetic suspension system, were created for the participants in a prospective study. Interface stress was measured as the peak pressure by using the F-socket transducers during stairs and ramp negotiation. RESULTS: Twelve individuals with transtibial amputation managed to complete the experiments. During the stair ascent and descent, the greatest peak pressure was observed in the prosthesis with the ...


Signal Quality Measures On Pulse Oximetry And Blood Pressure Signals Acquired From Self-Measurement In A Home Environment Jan 2015

Signal Quality Measures On Pulse Oximetry And Blood Pressure Signals Acquired From Self-Measurement In A Home Environment

Faculty of Engineering University of Malaya

Recently, decision support system (DSSs) have become more widely accepted as a support tool for use with telehealth systems, helping clinicians to summarize and digest what would otherwise be an unmanageable volume of data. One of the pillars of a home telehealth system is the performance of unsupervised physiological self-measurement by patients in their own homes. Such measurements are prone to error and noise artifact, often due to poor measurement technique and ignorance of the measurement and transduction principles at work. These errors can degrade the quality of the recorded signals and ultimately degrade the performance of the DSS system ...


Integration Of Biosensors Based On Microfluidic: A Review Jan 2015

Integration Of Biosensors Based On Microfluidic: A Review

Faculty of Engineering University of Malaya

Purpose - Biotechnology is closely associated to microfluidics. During the last decade, designs of microfluidic devices such as geometries and scales have been modified and improved according to the applications for better performance. Numerous sensor technologies existing in the industry has potential use for clinical applications. Fabrication techniques of microfluidics initially rooted from the electromechanical systems (EMS) technology. Design/methodology/approach - In this review, we emphasized on the most available manufacture approaches to fabricate microchannels, their applications and the properties which make them unique components in biological studies. Findings - Major fundamental and technological advances demonstrate the enhancing of capabilities and improving ...


Classification Of Eyelid Position And Eyeball Movement Using Eeg Signals Jan 2015

Classification Of Eyelid Position And Eyeball Movement Using Eeg Signals

Faculty of Engineering University of Malaya

Contamination of EOG activities in EEG signals remains a significant problem in designing the hybrid BCI system. Since EEG signals have always been contaminated by EOG artifacts, we employ these artifacts as inputs into our system. Therefore, in this study we utilized theEEG and its EOG artifacts as inputs to the hybrid BCI and evaluated the classification performance between thresholding and classifier techniques to determine the eyelid position and eyeball movement from EEG signals and its EOG artifacts in real-time. The EEG signals are recorded from the occipital (channel O2) and motor cortex (channel C3 and C4) on the scalp ...


Performance Comparison Of Windowing Techniques For Ecg Signal Enhancement, Innovative Research Publications Irp India, K.Sravan Kumar, Babak Yazdanpanah, Dr.G.S.N Raju Dec 2014

Performance Comparison Of Windowing Techniques For Ecg Signal Enhancement, Innovative Research Publications Irp India, K.Sravan Kumar, Babak Yazdanpanah, Dr.G.S.N Raju

Innovative Research Publications IRP India

Electrocardiogram (ECG) signal is generally corrupted by various artifacts like baseline wander, power line interference (50/60 Hz) and electromyography noise and these must be removed before diagnosis. The task propounded in this article is removal of low frequency interference i.e. baseline wandering and high frequency noise i.e. electromyography in ECG signal and digital filters are implemented to delete it. The digital filters accomplished are FIR with various windowing methods as of Rectangular, Hann, Blackman, Hamming, and Kaiser. The results received are at order of 300,450,600.The signal taken of the MIT-BIH database which contains the ...


Perspectives For Titanium-Derived Fillers Usage On Denture Base Composite Construction, Nidal Elshereksi Jul 2014

Perspectives For Titanium-Derived Fillers Usage On Denture Base Composite Construction, Nidal Elshereksi

Nidal Elshereksi

Poly(methyl methacrylate) (PMMA) is an extensively used material in dentistry because of its aesthetics, processability, and reparability. However, PMMA is still far from being ideal in fulfilling the mechanical requirements of prosthesis. PMMA-based denture base polymers exhibit low fracture resistance and radiopacity behavior. Efforts to improve the mechanical and radiopacity properties of denture base materials through inclusion of silica-based fillers are ongoing. Although silane-treated siliceous fillers are commonly used, they are not sufficiently strong.They also exhibit cracks, which either cut through the glass fillers or propagate around the filler particles. This defect occurs when the dental composites are ...


My Cv (2014), Hossein Gholizadeh Apr 2014

My Cv (2014), Hossein Gholizadeh

Hossein Gholizadeh

No abstract provided.


Vicon Motion System, Arezoo Eshraghi Mar 2014

Vicon Motion System, Arezoo Eshraghi

AREZOO ESHRAGHI

No abstract provided.


Cv, Arezoo Eshraghi Feb 2014

Cv, Arezoo Eshraghi

AREZOO ESHRAGHI

No abstract provided.


Correlation Between Energy Distribution Profile And Lev El Of Consciousness, D. K. Chaturvedi Dr. Jan 2014

Correlation Between Energy Distribution Profile And Lev El Of Consciousness, D. K. Chaturvedi Dr.

D. K. Chaturvedi Dr.

The purpose of this experimental study was to determine the energy levels corresponding to the different focal points (Chakras or centers) of the body, which is related with consciousness. In this experiment, the energy level is measured at four different centers, namely, the navel center, the heart center, the throat center and the eye center of the Human beings. The measurements have been taken using Energy Measurement System (EMS) developed at Department of Electrical Engineering, Dayalbagh Education Institute, Dayalbagh, Agra, India, which works on the principle of tissue resistance of body. The probe was placed at different centers and subsequent ...