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Articles 1 - 14 of 14
Full-Text Articles in Mechanical Engineering
Concurrent Detection And Isolation Of Cellular And Molecular Biomarkers, Wanfeng Huang
Concurrent Detection And Isolation Of Cellular And Molecular Biomarkers, Wanfeng Huang
Open Access Dissertations
Detection of cancer markers such as protein biomolecules and cancer cells in bodily fluids is of great importance in early diagnosis, prognosis as well as evaluation of therapy efficacy. Numerous devices have been developed for detecting either cellular or molecular targets, however there has not yet been a system that can simultaneously detect both cellular and molecular targets effectively. Molecule and cell-based assays are important because each type of target can tell a different story about the state of the disease and the two types of information can potentially be combined and/or compared for more accurate biological or clinical assessments. …
Nonlinear Dynamics Of Electrostatically Actuated M/Nems Plates To Include Casimir And Van Der Waals Effects, Reynaldo Oyervides
Nonlinear Dynamics Of Electrostatically Actuated M/Nems Plates To Include Casimir And Van Der Waals Effects, Reynaldo Oyervides
Theses and Dissertations - UTB/UTPA
The amplitude-frequency response and voltage-amplitude response of electrostatically actuated micro and nano-electromechanical systems (M/NEMS) clamped circular plates are investigated. The system is actuated by soft AC voltage at frequency near half natural frequency of the plate, and another case near natural frequency of the plate, they resulting in primary and parametric resonances of the system, respectively. The system is first analytically modeled using the Method of Multiple Scales (MMS). MMS results are then compared to Reduced Order Model (ROM) method frequency response numerical simulations. Besides MMS and ROM, time response simulations are conducted. The agreement of the frequency responses of …
Swelling-Etching Characterization Of Copper (I) Oxide - Pdms For The Development Of Micro/Nano - Particles Composite Mems Corrosion Sensor, Abdoul Kader Maiga
Swelling-Etching Characterization Of Copper (I) Oxide - Pdms For The Development Of Micro/Nano - Particles Composite Mems Corrosion Sensor, Abdoul Kader Maiga
Graduate Theses and Dissertations
The primary objective for this thesis is to contribute to the understanding of the oxide removal process for a corrosion sensing device. The goal for designing such a device is for monitoring corrosion on metallic structures. The sensing material (6.35mm x 1mm discs) of the device is composed of copper (I) oxide particles mixed in some polydimethylsiloxane (PDMS). The PDMS, “housing,” is meant for controlling the oxidation rate through the sensing material. A solvent was used to facilitate the etchant diffusion through the PDMS matrix. Toluene and acetic acid were the ideal solvent and etchant, respectively, for carrying out the …
Mems Lab Simulation Tool, Oluwatosin D. Adeosun, Sambit Palit, Ankit Jain, Muhammad A. Alam
Mems Lab Simulation Tool, Oluwatosin D. Adeosun, Sambit Palit, Ankit Jain, Muhammad A. Alam
The Summer Undergraduate Research Fellowship (SURF) Symposium
MEMS actuators have multiple design applications. Understanding their behavior as well as the ability to predict their actuation characteristics and voltage response is important when designing these actuators. In order to know these devices will behave, designers have to solve multiple analytical equations and experiments that can be very time consuming. Over the course of the summer a tool was created on nanoHUB that will allow users to enter information about a MEMS actuator and provide the voltage response of the actuator. To create the tool, scaling equations were first provided for various geometry configurations and the equations were next …
Design, Fabrication, Testing Of Cnt Based Isfet And Characterization Of Nano/Bio Materials Using Afm, Zhuxin Dong
Design, Fabrication, Testing Of Cnt Based Isfet And Characterization Of Nano/Bio Materials Using Afm, Zhuxin Dong
Graduate Theses and Dissertations
A combination of Carbon Nanotubes (CNTs) and Ion Selective Field Effect Transistor (ISFET) is designed and experimentally verified in order to develop the next generation ion concentration sensing system. Micro Electro-Mechanical System (MEMS) fabrication techniques, such as photolithography, diffusion, evaporation, lift-off, packaging, etc., are required in the fabrication of the CNT-ISFET structure on p-type silicon wafers. In addition, Atomic Force Microscopy (AFM) based surface nanomachining is investigated and used for creating nanochannels on silicon surfaces. Since AFM based nanomanipulation and nanomachining is highly controllable, nanochannels are precisely scratched in the area between the source and drain of the FET where …
Computational Design Of The Electrical And Mechanical Performance Of Steerable Mems Antennas, Morgan Andrew Roddy
Computational Design Of The Electrical And Mechanical Performance Of Steerable Mems Antennas, Morgan Andrew Roddy
Graduate Theses and Dissertations
This thesis describes the origins, improvements, and variations of a broadband microwave antenna that can be beam-steered by a micro-electromechanical system (MEMS). The steerable MEMS antenna of this work was comprised of a planar antenna on top of a Silicon membrane. The membrane is etched to create a gimbal hinge structure and a platform which supported the antenna and gave it one or two degrees of freedom of rotation. The antennas presented were broadband and fed by a coplanar waveguide (CPW) transmission line which traversed the hinge structure. The antenna's orientation in space was designed to be changed through electrostatic …
Simulation Of A Capacitive Micromachined Ultrasonic Transducer With A Parylene Membrane And Graphene Electrodes, David Sadat
Simulation Of A Capacitive Micromachined Ultrasonic Transducer With A Parylene Membrane And Graphene Electrodes, David Sadat
Electronic Theses and Dissertations
Medical ultrasound technology accounts for over half of all imaging tests performed worldwide. In comparison to other methods, ultrasonic imaging is more portable and lower cost, and is becoming more accessible to remote regions where traditionally no medical imaging can be done. However, conventional ultrasonic imaging systems still rely on expensive PZT-based ultrasound probes that limit broader applications. In addition, the resolution of PZT based transducers is low due to the limitation in hand-fabrication methods of the piezoelectric ceramics. Capacitive Micromachined Ultrasonic Transducers (CMUTs) appears as an alternative to the piezoelectric (PZT) ceramic based transducer for ultrasound medical imaging. CMUTs …
A Solid State Nitrogen Gas Generating Chip And Applications For Picosatellites, Kyle Godin
A Solid State Nitrogen Gas Generating Chip And Applications For Picosatellites, Kyle Godin
Graduate Theses and Dissertations
A microscale gas generating chip has many applications; in this study, applications relating to picosatellites have been considered. Cube satellites, a type of picosatellite, are of mass around one kilogram and side length 10cm x 10cm x 10cm. Their launches are becoming more numerous since their debut ten years ago. Their low cost and deployment system makes space accessible to agencies hitherto barred from it, such as universities and small governments. However, their power, mass, and volume budget is extremely tight. A microscale gas chip could compete with other designs for attitude control devices, most not flown yet as cube …
Investigation Of The Design Of A Bistable Micro-Chemical-Mechanical Device Utilizing Lateral Buckling, Susan Lyn Barnes
Investigation Of The Design Of A Bistable Micro-Chemical-Mechanical Device Utilizing Lateral Buckling, Susan Lyn Barnes
Honors Theses
The Gracias Laboratory at Johns Hopkins University has developed microgrippers which utilize chemically-actuated joints to be used in micro-surgery. These grippers, however, take up to thirty minutes to close fully when activated biochemicals in the human body. This is very problematic and could limit the use of the devices in surgery. It is the goal of this research to develop a gripper that uses theGracias Laboratory's existing joints in conjunction with mechanical components to decrease the closing time. The purpose of including the mechanical components is to induce a state of instability at which time a small perturbation would cause …
Measuring Skeletal Kinematics With Accelerometers On The Skin Surface, Kevin Curtis Ayer
Measuring Skeletal Kinematics With Accelerometers On The Skin Surface, Kevin Curtis Ayer
LSU Master's Theses
The most common motion analysis method uses cameras to track the position of markers on bodily surfaces over time. Although each species has a common skeletal frame to reference recorded motions, the soft tissue covering each is not rigid. Markers, therefore, experience motion relative to the bone and do not accurately portray underlying bone activity. This limits clinical use of motion studies and the understanding of joint motion. Use of MEMS accelerometers for removing soft tissue artifact, motion relative to the bone, from surface measurements and determining the position of the underlying bone was investigated. An animal limb was modeled …
Rapid Prototyping Of Microfluidic Packages, Michael Pepper
Rapid Prototyping Of Microfluidic Packages, Michael Pepper
Electronic Theses and Dissertations
In the area of MEMS there exists a tremendous need for communication between the micro-device and the macro world. A standard protocol or at least multiple standards would be of great use. Electrical connections have been standardized for many uses and configurations by the integrated circuit industry. Standardization in the IC industry has created a marketplace for digital devices unprecedented. In addition to the number of "off the shelf" products available, there exists the possibility for consumers to mix and match many devices from many different manufacturers. This research proposes some similar solutions as those for integrated circuits for fluid …
Fabrication Of High Aspect Ratio Vibrating Cylinder Microgyroscope Structures By Use Of The Liga Process, Yohannes Mamo Desta
Fabrication Of High Aspect Ratio Vibrating Cylinder Microgyroscope Structures By Use Of The Liga Process, Yohannes Mamo Desta
LSU Doctoral Dissertations
Inertial grade microgyroscopes are of great importance to improve and augment inertial navigation systems based on GPS for industrial, automotive, and military applications. The efforts by various research groups worldwide to develop inertial grade microgyroscopes have not been successful to date. In 1994, the Department of Mechanical Engineering at Louisiana State University and SatCon Technology Corporation (Boston, Massachusetts) proposed a series of shock tolerant micromachined vibrating cylinder rate gyroscopes with aspect ratios of up to 250:1 to meet the needs of inertial navigation systems based on existing conventional vibrating cylinder gyroscopes. Each microgyroscope consisted of a tall thin shell metallic …
Ultra Deep Su-8 Manufacturing And Characterization For Mems Applications, Charles Joseph Becnel
Ultra Deep Su-8 Manufacturing And Characterization For Mems Applications, Charles Joseph Becnel
LSU Master's Theses
The Micro Systems Engineering Team (mSET) at Louisiana State University (LSU) utilizes microfabrication for a number of heat and mass transfer devices. These include cross flow heat exchangers, mechanical seals with integrated micro heat exchangers, catalytic converters, and micro reactors. In all of these applications, micro honeycomb arrays provide increased surface area per unit volume which significantly enhances heat and mass transfer. In the past, it was only possible to fabricate SU-8 structures approximately 1.5 mm tall. Furthermore, qualitatively, it is much more difficult to fabricate close packed feature arrays than sparse arrays. For many of the previously mentioned applications, …
Tribological Behavior Of Nanostructured Nickel, Dean Joseph Guidry
Tribological Behavior Of Nanostructured Nickel, Dean Joseph Guidry
LSU Master's Theses
The present study reports the effects of electroplating parameters on the microstructure, and thus the mechanical and tribological properties, of nanostructured nickel. Electroplating was conducted in a Watt's type bath with a pH of 3.0 carried out using direct current in galvanostatic mode at current densities of 30 mA/cm2 and 15 mA/cm2 in electroplating bath temperatures of 30°C and 50°C. Grain size and distributions were determined from TEM (Transmission Electron Microscope) and SEM (Scanning Electron Microscope) micrographs. Tribological tests were carried out on a pin-on-disc type tribometer. The same tests were conducted on Ni-200 for the purpose of …