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Full-Text Articles in Engineering

High Throughput Wear Debris Detection In Lubricants Using A Resonance Frequency Division Multiplexed Sensor, Li Du, Xiaoliang Zhu, Yu Han, Jiang Zhe Apr 2015

High Throughput Wear Debris Detection In Lubricants Using A Resonance Frequency Division Multiplexed Sensor, Li Du, Xiaoliang Zhu, Yu Han, Jiang Zhe

Dr. Jiang Zhe

With a long time goal of detecting signs of potential machine failure, we demonstrate a proof-of-principle multiplexed, multichannel, inductive pulse sensor based on resonant frequency division multiplexing for high throughput detection of micro-scale metallic debris in lubricants. In the four-channel sensor, each sensing coil is connected to a specific external capacitance to form a parallel LC circuit that has a unique resonant frequency. Only one combined sinusoidal excitation signal consisting of four frequencies components that are close to the 4 sensing channels’ resonant frequencies was applied to the sensor, and only one combined voltage response was measured. Because each sensing …


On-Line Wear Debris Detection In Lubricating Oil For Condition Based Health Monitoring Of Rotary Machinery, Li Du, Jiang Zhe Apr 2015

On-Line Wear Debris Detection In Lubricating Oil For Condition Based Health Monitoring Of Rotary Machinery, Li Du, Jiang Zhe

Dr. Jiang Zhe

Condition based monitoring has become essential in maintaining and extending the health of high-speed rotating and reciprocating machinery. One effective approach to detect signs of potential failure of a rotating or reciprocating machine is to examine the wear debris in its lubricating oil. Recent patents and research articles on on-line wear debris detection in lubricating oil are reviewed in this paper, including electrical impedance detection, acoustic detection, optical detection, pressure detection, online x-ray spectrography, resonant frequency detection, and electrostatic charge detection. Advantages and limitations of each detection method are discussed.


A High Throughput Inductive Pulse Sensor For Online Oil Debris Monitoring, Li Du, Jiang Zhe Apr 2015

A High Throughput Inductive Pulse Sensor For Online Oil Debris Monitoring, Li Du, Jiang Zhe

Dr. Jiang Zhe

A high throughput inductive pulse sensor based on inductive Coulter counting principle for detecting metallic wear debris in lubrication oil is presented. The device detects the passage of metallic debris by monitoring the inductance change of a two-layer planar coil with a meso-scale fluidic pipe crossing its center, which is designed to attain high throughput without sacrificing the sensitivity. The testing results using iron and copper particles ranging in size from 50 to 150 μm have demonstrated that the device is capable of detecting and distinguishing ferrous and non-ferrous metallic debris in lubrication oil with a high throughput.


Capacitive Coulter Counting: Detection Of Metal Wear Particles In Lubricant Using A Microfluidic Device, Srinidhi Murali, Xingao Xia, Ashish Jagtiani, Joan Carletta, Jiang Zhe Apr 2015

Capacitive Coulter Counting: Detection Of Metal Wear Particles In Lubricant Using A Microfluidic Device, Srinidhi Murali, Xingao Xia, Ashish Jagtiani, Joan Carletta, Jiang Zhe

Dr. Jiang Zhe

A microfluidic device based on the capacitance Coulter counting principle to detect metal debris particles in lubricant oil is presented. The device scans each individual metal debris particle as they pass through a microfluidic channel by monitoring the capacitance change. We first proved the feasibility of using the capacitance Coulter counting principle for detecting metal particles in a fluidic channel. Next, we tested the microfluidic device with aluminum abrasive particles ranging from 10 to 25 µm; the testing results show the microfluidic device is capable of detecting metal wear particles in low-conductive lubricant oil. The design concept demonstrated here can …


A Capillary Microgripper Based On Electrowetting, Abhay Vasudev, Jiang Zhe Apr 2015

A Capillary Microgripper Based On Electrowetting, Abhay Vasudev, Jiang Zhe

Dr. Jiang Zhe

An electrowetting based capillary microgripper, which can pick up and release micro-objects, is presented. Electrowetting was utilized to dynamically change the contact angle between the liquid bridge and the gripper surface to control the capillary lifting forces. A coplanar interdigitated goldelectrode pair was employed to simplify the microfabrication. The lifting force generated by the microgripper was experimentally characterized. The pickup and release routine was demonstrated for various micro glass beads whose weight ranges from 77 to 136 μN. The design, microfabrication, and testing of the microgripper are presented.


A Microfluidic Multichannel Resistive Pulse Sensor Using Frequency Division Multiplexing For High Throughput Counting Of Micro Particles, Ashish Jagtiani, Joan Carletta, Jiang Zhe Apr 2015

A Microfluidic Multichannel Resistive Pulse Sensor Using Frequency Division Multiplexing For High Throughput Counting Of Micro Particles, Ashish Jagtiani, Joan Carletta, Jiang Zhe

Dr. Jiang Zhe

In this work we demonstrate an on-chip multiplexed multichannel resistive pulse sensor (Coulter counter) for high throughput counting of microscale particles. The design, fabrication and testing of this device are presented. The high throughput counting is a result of using multiple parallel microfluidic channels to analyze the sample. Detection is achieved by using frequency division multiplexing; each microchannel is modulated with its own known and unique frequency, a combined measurement is made across a single pair of electrodes, and the measured signal is demodulated to determine the signal across each individual channel. Testing results using 30 µm polystyrene particles demonstrate …


Postsynthetic Surface Functionalization, Postsynthetic Surface Functionalization, Encapsulation, And Releasing Studies Of A Novel Polymer Nanocapsule, Duangruthal Sridaeng, Jacob Weingart, Nuanphun Chantarasiri, Jiang Zhe, J. Hu Apr 2015

Postsynthetic Surface Functionalization, Postsynthetic Surface Functionalization, Encapsulation, And Releasing Studies Of A Novel Polymer Nanocapsule, Duangruthal Sridaeng, Jacob Weingart, Nuanphun Chantarasiri, Jiang Zhe, J. Hu

Dr. Jiang Zhe

Postsynthetic surface functionalizations of the amphiphilic poly(allyamine)-g-poly(t-butylacrylate) nanocapsule of 50–100 nm diameters are reported. The hydrophobic poly(t-butylacrylate) surface of the polymer nanocapsules were successfully functionalized with poly(acrylate) and poly(ethylene glycol). These new nanocapsules were investigated for their water dispersibility, encapsulation and controlled releasing properties with fluorescein, an anionic fluorescence probe, and 5-fluorouacil, an anticancer drug as the model compounds. The postsynthetic surface funcitionalization approach of the cross-linked polymer nanocapsules shows promise for improving the biocompatibility and aqueous dispersibility of the nanocapules without disrupting the encapsulation and releasing properties of the polymer nanocapsules.


Novel Quantitative Macro Biomolecule Analysis Based On A Micro Coulter Counter, Y Han, H. Wu, F. Liu, Gang Cheng, Jiang Zhe Apr 2015

Novel Quantitative Macro Biomolecule Analysis Based On A Micro Coulter Counter, Y Han, H. Wu, F. Liu, Gang Cheng, Jiang Zhe

Dr. Jiang Zhe

We demonstrate quantitative biomolecule analysis using a micro coulter counter. Specific binding between antibody functionalized microparticles and target biomolecule cause large aggregates of microparticles. The micro coulter counter was employed to measure aggregation ratio, ratio of the aggregate counts to the total particle counts. Goat anti-rabbit IgG, used as a model biomarker, were tested in this paper. The experiment results showed that the aggregation ratio increases with the increasing biomolecule concentration, and the detectable concentration range from 16 to 160 ng/ml was achieved.


An Impedimetric Approach For Accurate Particle Sizing Using A Micro Coulter Counter, Ashish Jagtiani, Joan Carletta, Jiang Zhe Apr 2015

An Impedimetric Approach For Accurate Particle Sizing Using A Micro Coulter Counter, Ashish Jagtiani, Joan Carletta, Jiang Zhe

Dr. Jiang Zhe

In this paper, we present the design, impedimetric characterization and testing of a microfabricated Coulter counter for particle size measurement that uses a pair of thin film coplanar Au/Ti electrodes. An electrical equivalent circuit model of the designed device is analyzed. Accurate measurement of particle size was achieved by operating the device at a frequency for which the overall impedance is dominated by the channel resistance. A combination of design features, including the use of a pair of sensing electrodes with a surface area of 100 µm by 435 µm, a spacing of 1785 µm between the two sensing electrodes …


Wavelet Transform-Based Methods For Denoising Of Coulter Counter, Ashish Jagtiani, Rupesh Sawant, Joan Carletta, Jiang Zhe Apr 2015

Wavelet Transform-Based Methods For Denoising Of Coulter Counter, Ashish Jagtiani, Rupesh Sawant, Joan Carletta, Jiang Zhe

Dr. Jiang Zhe

A process based on discrete wavelet transforms is developed for denoising and baseline correction of measured signals from Coulter counters. Given signals from a particular Coulter counting experiment, which detect passage of particles through a fluid-filled microchannel, the process uses a cross-validation procedure to pick appropriate parameters for signal denoising; these parameters include the choice of the particular wavelet, the number of levels of decomposition, the threshold value and the threshold strategy. The process is demonstrated on simulated and experimental single channel data obtained from a particular multi-channel Coulter counter processing. For these example experimental signals from 20 µm polymethacrylate …


Real-Time Monitoring Of Wear Debris In Lubrication Oil Using A Microfluidic Inductive Coulter Counting Device, Li Du, Jiang Zhe, Joan Carletta, Robert Veillette, Fred Choy Apr 2015

Real-Time Monitoring Of Wear Debris In Lubrication Oil Using A Microfluidic Inductive Coulter Counting Device, Li Du, Jiang Zhe, Joan Carletta, Robert Veillette, Fred Choy

Dr. Jiang Zhe

A microfluidic device based on an inductive Coulter counting principle to detect metal wear particles in lubrication oil is presented. The device detects the passage of ferrous and nonferrous particles by monitoring the inductance change of an embedded coil. The device was tested using iron and copper particles ranging in size from 50 to 125 μm. The testing results have demonstrated that the device is capable of detecting and distinguishing ferrous and nonferrous metal particles in lubrication oil; such particles can be indicative of potential machine faults in rotating and reciprocating machinery.


Soft Microgripping Using Ionic Liquid Droplet For High Temperature And Vacuum Applications, Abdullah Amin, Ashish Jagtiani, Abhay Vasudev, Jun Hu, Jiang Zhe Apr 2015

Soft Microgripping Using Ionic Liquid Droplet For High Temperature And Vacuum Applications, Abdullah Amin, Ashish Jagtiani, Abhay Vasudev, Jun Hu, Jiang Zhe

Dr. Jiang Zhe

Aqueous droplet-based micro-gripper has been used for micro-assembly. However they cannot be used for high temperature and vacuum applications. Ionic liquids, organic salts that have a lower melting point temperature, appear suitable for droplet-based micro-gripping application in high temperature and vacuum environments because of their nonvolatility and thermal stability. In this paper, we demonstrated the use of ionic liquid as the operating liquid for micro-gripping applications in high temperatures (up to 110 °C) and vacuum (up to 24 inch Hg) environments. Electrowetting was utilized to dynamically change the contact angle of a 1-butyl-3-methylimidazolium hexafluorophosphate (BmimPF6) liquid bridge to control the …


Static And Dynamic Responsive Behavior Of Polyelectrolyte Brushes Under External Electrical Field, Hui Ouyang, Zhenhai Xia, Jiang Zhe Apr 2015

Static And Dynamic Responsive Behavior Of Polyelectrolyte Brushes Under External Electrical Field, Hui Ouyang, Zhenhai Xia, Jiang Zhe

Dr. Jiang Zhe

The static and dynamic behaviors of partially charged and end-grafted polyelectrolyte brushes in response to electric fields were investigated by means of molecular dynamics simulation. The results show that the polymer brushes can be partially or fully stretched by applying an external electric field. Moreover, the brushes can switch reversibly from collapsed to stretched states, fully responding to the AC electric stimuli, and the gating response frequency can reach a few hundred MHz. The effects of the grafting density, the charge fraction of the brushes and the strength of the electric field on the average height of the polymer brushes …


A Microfluidic Mixer Utilizing Electrokinetic Relay Switching And Asymmetric Flow Geometries, Yiou Wang, Jiang Zhe, Prashanta Dutta, Benjamin Chung Apr 2015

A Microfluidic Mixer Utilizing Electrokinetic Relay Switching And Asymmetric Flow Geometries, Yiou Wang, Jiang Zhe, Prashanta Dutta, Benjamin Chung

Dr. Jiang Zhe

No abstract provided.


High School Bridge Program: A Multidisciplinary Stem Research Program, Jiang Zhe, Dennis Doverspike, Julie Zhao, Paul C. Lam, Craig C. Menzemer Apr 2015

High School Bridge Program: A Multidisciplinary Stem Research Program, Jiang Zhe, Dennis Doverspike, Julie Zhao, Paul C. Lam, Craig C. Menzemer

Dr. Jiang Zhe

A Science, Technology, Engineering and Math (STEM) summer Bridge Program was developed for high school students. The program was designed to encourage students to consider choosing an engineering major in college and to explore STEM as a future career. This was accomplished through a 10-week program involving multidisciplinary research activities. The participants in the program included 33 high school students. Among former participants in position to make a choice in terms of attending college, 100% had chosen to continue on in college, and 86% had chosen to major in a STEM area. The results indicated that that the program had …


An Evaluation Of A Stem Program For Middle School Students On Learning Disability Related Ieps, Paul C. Lam, Dennis Doverspike, Julie Zhao, Jiang Zhe, Craig C. Menzemer Apr 2015

An Evaluation Of A Stem Program For Middle School Students On Learning Disability Related Ieps, Paul C. Lam, Dennis Doverspike, Julie Zhao, Jiang Zhe, Craig C. Menzemer

Dr. Jiang Zhe

A year long Science, Technology, Engineering and Math (STEM) program was developed for middle schools students on Individualized Education Programs (IEPs) involving learning disabilities. The workshops were designed to encourage students both on IEPs and not on IEPs to explore STEM as a future career choice by building their knowledge and confidence. The participants in the workshops included 11 students on IEPs and 15 students not on IEPs. Parents also provided feedback regarding their attitudes toward the program. The results indicated that there were increases in student participant knowledge and career interest for both the students not on IEPs and …


Passive Continuous Particle Focusing In A Microchannel With Symmetric Sharp Corner Structures, Liang-Liang Fan, Liang Zhao, Xu-Kun He, Hand Yu, Qing-Yu Wei, Jiang Zhe Apr 2015

Passive Continuous Particle Focusing In A Microchannel With Symmetric Sharp Corner Structures, Liang-Liang Fan, Liang Zhao, Xu-Kun He, Hand Yu, Qing-Yu Wei, Jiang Zhe

Dr. Jiang Zhe

We report a continuous passive particle focusing method using a novel microchannel with symmetric sharp corners which induce curved streamlines and large centrifugal force on particles. At appropriate flow rate, the centrifugal force generated on particles exceeds the inertial lift force; particles driven by the centrifugal force migrate toward the center of the microchannel, achieving continuous particle focus-ing. With simple structure and operation, this method can be potentially used in particle focusing and ex-traction processes in a variety of lab-on-a chip applications.


A Low-Voltage Droplet Microgripper For Micro-Object Manipulation, Abhay Vasudev, Ashish Jagtiani, Li Du, Jiang Zhe Apr 2015

A Low-Voltage Droplet Microgripper For Micro-Object Manipulation, Abhay Vasudev, Ashish Jagtiani, Li Du, Jiang Zhe

Dr. Jiang Zhe

We present a low-voltage microgripper utilizing a liquid droplet to pick up and release micro-objects. Lifting force is generated by a liquid bridge formed between the gripper surface and an object. Electrowetting was used to dynamically change the capillary lifting forces and enable easy object release. The driving voltage was applied to a pair of coplanar interdigitated electrodes, eliminating the need for an electrode on top of the droplet and thus significantly facilitating object manipulation. A barium strontium titanate insulation layer was used to lower the driving voltage. Experiments indicated that the lifting forces can be as high as 213 …


Inductive Coulter Counting: Detection And Differentiation Of Metal Wear Particles In Lubricant, Li Du, Jiang Zhe, Robert Veillette Apr 2015

Inductive Coulter Counting: Detection And Differentiation Of Metal Wear Particles In Lubricant, Li Du, Jiang Zhe, Robert Veillette

Dr. Jiang Zhe

A device based on an inductive Coulter counting principle for detecting metal particles in lubrication oil is presented. The device detects the passage of ferrous and nonferrous particles by monitoring the inductance change in a coil. First, the sensing principle is demonstrated at the mesoscale using a solenoid. Next, a small planar coil suitable for use in a microscale device is tested. Static tests are conducted on the planar coil using iron and aluminum particles ranging from 80 to 500 µm. The testing results show that the coil can be used to detect and distinguish ferrous and nonferrous metal particles …


Recent Advances In Particle And Droplet Manipulation For Lab-On-A-Chip Devices Based On Surface Acoustic Wave, Zhuochen Wang, Jiang Zhe Apr 2015

Recent Advances In Particle And Droplet Manipulation For Lab-On-A-Chip Devices Based On Surface Acoustic Wave, Zhuochen Wang, Jiang Zhe

Dr. Jiang Zhe

Manipulation of microscale particles and fluid liquid droplets is an important task for lab-on-a-chip devices for numerous biological researches and applications, such as cell detection and tissue engineering. Particle manipulation techniques based on surface acoustic waves (SAWs) appear effective for lab-on-a-chip devices because they are non-invasive, compatible with soft lithography micromachining, have high energy density, and work for nearly any type of microscale particles. Here we review the most recent research and development of the past two years in SAW based particle and liquid droplet manipulation for lab-on-a-chip devices including particle focusing and separation, particle alignment and patterning, particle directing, …


A Rapid Magnetic Particle Driven Micromixer, Yiou Wang, Jiang Zhe, Benjamin Chung, Prashanta Dutta Apr 2015

A Rapid Magnetic Particle Driven Micromixer, Yiou Wang, Jiang Zhe, Benjamin Chung, Prashanta Dutta

Dr. Jiang Zhe

Performances of a magnetic particle driven micromixer are predicted numerically. This micromixer takes advantages of mixing enhancements induced by alternating actuation of magnetic particles suspended in the fluid. Effects of magnetic actuation force, switching frequency and channel’s lateral dimension have been investigated. Numerical results show that the magnetic particle actuation at an appropriate frequency causes effective mixing and the optimum switching frequency depends on the channel’s lateral dimension and the applied magnetic force. The maximum efficiency is obtained at a relatively high operating frequency for large magnetic actuation forces and narrow microchannels. If the magnetic particles are actuated with a …


A New Look At Optimum Design For Convecting-Radiating Annular Fins Of Trapezoidal Profile, Benjamin T.F. Chung Apr 2015

A New Look At Optimum Design For Convecting-Radiating Annular Fins Of Trapezoidal Profile, Benjamin T.F. Chung

Dr. Benjamin T.F. Chung

This paper deals with a controversial problem in answering the question “Does the optimum fin design always exist? If not, what are the optimization ranges and limitations?” These authors employ a general example of convecting-radiating trapezoidal annular fin with heat transfer at the tip and wall resistance at the interface. The present results indicate that the answer to the above first question is negative. The ranges of fin optimum design under different thermal and physical conditions are proposed. The effects of Biot number, radiation number, the heat loss at the tip, fin profile and overall wall resistance on fin optimization …


Ranges And Limitations Of Optimum Design For Convecting-Radiating Annular Fins Of Trapezoidal Profile, Benjamin T.F. Chung, Y. Zhou, Y. Wang, L. T. Yeh Apr 2015

Ranges And Limitations Of Optimum Design For Convecting-Radiating Annular Fins Of Trapezoidal Profile, Benjamin T.F. Chung, Y. Zhou, Y. Wang, L. T. Yeh

Dr. Benjamin T.F. Chung

This paper deals with a controversial problem in answering the question “Does the optimum fin design always exist? If not, what are the optimization ranges and limitations?” These authors employ a general example of convecting-radiating trapezoidal annular fin with heat transfer at the tip and wall resistance at the interface. The present results indicate that the answer to the above first question is negative. The ranges of fin optimum design under different thermal and physical conditions are proposed. The effects of Biot number, radiation number, the heat loss at the tip, fin profile and overall wall resistance on fin optimization …


A Cell Model For Ductile Fracture With Applications, C. Fong Shih, Li Cheng, J. Faleskog, Xiaosheng Gao Apr 2015

A Cell Model For Ductile Fracture With Applications, C. Fong Shih, Li Cheng, J. Faleskog, Xiaosheng Gao

Dr. Xiaosheng Gao

No abstract provided.


Analysis Of Ductile To Cleavage Transition In Part-Through Cracks Using The Cell Model Incorporating Statistics, Xiaosheng Gao, J. Faleskog, C. Fong Shih Apr 2015

Analysis Of Ductile To Cleavage Transition In Part-Through Cracks Using The Cell Model Incorporating Statistics, Xiaosheng Gao, J. Faleskog, C. Fong Shih

Dr. Xiaosheng Gao

This paper describes an approach to study ductile/cleavage transition in ferritic steels using the methodology of a cell model for ductile tearing incorporating weakest link statistics. The model takes into account the constraint effects and puts no restriction on the extent of plastic deformation or amount of ductile tearing preceding cleavage failure. The parameters associated with the statistical model are calibrated using experimental cleavage fracture toughness data, and the effect of threshold stress on predicted cleavage fracture probability is investigated. The issue of two approaches to compute Weibull stress, the ‘history approach’ and the ‘current approach’, is also addressed. The …


A Mechanism-Based Approach For Predicting Ductile Fracture Of Metallic Alloys, Xiaosheng Gao Apr 2015

A Mechanism-Based Approach For Predicting Ductile Fracture Of Metallic Alloys, Xiaosheng Gao

Dr. Xiaosheng Gao

Ductile fracture in metallic alloys often follows a multi-step failure process involving void nucleation, growth and coalescence. Because of the difference in orders of magnitude between the size of the finite element needed to resolve the microscopic details and the size of the engineering structures, homogenized material models, which exhibits strain softening, are often used to simulate the crack propagation process. Various forms of porous plasticity models have been developed for this purpose. Calibration of these models requires the predicted macroscopic stress-strain response and void growth behavior of the representative material volume to match the results obtained from detailed finite …


Enabling And Understanding Failure Of Engineering Structures Using The Technique Of Cohesive Elements, H. Jiang, Xiaosheng Gao, T. S. Srivatsan Apr 2015

Enabling And Understanding Failure Of Engineering Structures Using The Technique Of Cohesive Elements, H. Jiang, Xiaosheng Gao, T. S. Srivatsan

Dr. Xiaosheng Gao

In this paper, we describe a cohesive zone model for the prediction of failure of engineering solids and/or structures. A damage evolution law is incorporated into a three-dimensional, exponential cohesive law to account for material degradation under the influence of cyclic loading. This cohesive zone model is implemented in the finite element software ABAQUS through a user defined subroutine. The irreversibility of the cohesive zone model is first verified and subsequently applied for studying cyclic crack growth in specimens experiencing different modes of fracture and/or failure. The crack growth behavior to include both crack initiation and crack propagation becomes a …


Numerical Modeling Of The Constraint Effects On Cleavage Fracture Toughness, Sunil Prakash, Xiaosheng Gao, T. S. Srivatsan Apr 2015

Numerical Modeling Of The Constraint Effects On Cleavage Fracture Toughness, Sunil Prakash, Xiaosheng Gao, T. S. Srivatsan

Dr. Xiaosheng Gao

Cleavage fracture has been an important subject for engineers primarily because of its catastrophic nature and consequences. Experimental studies of cleavage fracture did reveal a considerable amount of scatter and provided evidence of noticeable constraint effects. This did provide the motivation for the development of statistical-based and micromechanics-based methods in order to both study and analyze the problem. The Weibull stress model, which is based on the weakest link statistics, uses two parameters (m and σ u) to effectively describe the inherent distribution of the micro-scale cracks once plastic deformation has occurred and to concurrently define the relationship between the …


Analysis Of Loading Rate Effects On Cleavage Fracture Toughness Of Ferritic Steels, Xiaosheng Gao, Robert H. Dodds Jr. Apr 2015

Analysis Of Loading Rate Effects On Cleavage Fracture Toughness Of Ferritic Steels, Xiaosheng Gao, Robert H. Dodds Jr.

Dr. Xiaosheng Gao

No abstract provided.


Intelligent Identification Of Childhood Musical Murmurs, Yuerong Chen, Shengyong Wang, Chia-Hsuan Shen, Fred Choy Apr 2015

Intelligent Identification Of Childhood Musical Murmurs, Yuerong Chen, Shengyong Wang, Chia-Hsuan Shen, Fred Choy

Fred K. Choy

Heart murmurs are often the first signs of heart valvular disorders. However, most heart murmurs detected in children are innocent musical murmurs (also called Still's murmurs), which should be distinguished from other murmur types that are mostly pathological, such as regurgitant, obstructive, and flow murmurs. In order to reduce both unnecessary healthcare expenditures and parental anxiety, this study aims to develop algorithms for intelligently identifying musical murmurs in children. Discrete wavelet transform was applied to phonocardiographic signals to extract features. Singular value decomposition was applied on the matrix derived from continuous wavelet transform to extract extra features. The sequential forward …