Engineering Commons^™

Developing Compact Models For Passive Devices On Ibm 45nm Cmos Soi Technology, Yufei Feng, Yanfei Shen, Saeed Mohammadi

The Summer Undergraduate Research Fellowship (SURF) Symposium

The standard IBM 45 nm technology is widely adopted for industrial and academic purpose by integrates circuit designers. Original models provided by foundry are not accurate, which might cause inaccuracy in circuit simulations. Equivalent circuit models, using RLC elements to simulate electrical component, will effectively deliver their electrical performance. This study consists of four steps to construct these models. First, Cadence Virtuoso, the commercial circuit design software was used to run simulations and extract data for different device parameters. Second, analyzing tools, like Microsoft Excel or Matlab, are used to analyze the extracted data. Then, equations are written for each …

Microthruster Fabrication And Characterization: In Search Of The Optimal Nozzle Geometry For Microscale Rocket Engines, Katherine L. Fowee, Alina Alexeenko

The Summer Undergraduate Research Fellowship (SURF) Symposium

A major consideration in microsatellite design is the engineering of micropropulsion systems that can deliver the required thrust efficiently with tight restrictions on space, weight, and power. Cold gas thrusters are one solution to the demand for smaller propulsion systems to accommodate the advancements in technology that have allowed for a reduction in the size and thus the cost of satellites. While much research has been done in understanding the flow regimes within these microthrusters, there is a need to understand how different nozzle designs affect microthruster performance. This requires that experimental data be collected on varying nozzles shapes (orifices, …

Synthesis And Characterization Of Microporous And Mesoporous Catalysts For Shale Gas Upgrading, Danesh Contractor, Ravi Joshi, Rajamani Gounder

The Summer Undergraduate Research Fellowship (SURF) Symposium

The petroleum industry is gradually shifting from using naphtha to ethane as its feedstock and new ethane steam crackers are being built. Using ethane as a feedstock produces more ethene and less co-products such as propene, aromatics and C4 alkenes. Thus, the shift in feedstock will reduce the availability of these co-products. Developing methods for the interconversion of alkenes, and specifically using ethene as a reactant, can solve this problem.

This project focuses on synthesis and characterization of zeolites with the BEA framework topology, and their nickel exchanged versions as potential ethene dimerization catalysts. In future work, these materials will …

Energy Measurement Of Spdy Protocol On Mobile Platform, Zisheng Liao, Ashiwan Sivakumar, Sanjay Rao

The Summer Undergraduate Research Fellowship (SURF) Symposium

The past few years have witnessed an explosive growth in mobile Internet data traffic with web browsing being one of the key activities on mobile devices. There is tremendous interest in optimizing mobile web. In this regard, a new protocol called SPDY was introduced by Google to augment web browsing, however it's impact on the device energy consumption is not clearly understood. In this work we evaluate the energy characteristics of SPDY-based web browsing on mobile devices. In order to measure the energy consumption of web activities, we use AT&T’s ARO [1]. This tool is widely accepted and used by …

Radiation Measurements And Data Analysis Of Turbulent Premixed Lean Flame, Yunzhe Yang, Dong Han, Jay P. Gore

The Summer Undergraduate Research Fellowship (SURF) Symposium

An accurate understanding of the radiation transfer in turbulent premixed lean flame is critical for improving energy efficiencies and reducing emissions such as nitric oxide and soot. Radiation measurement is an effective and nonintrusive way to study the radiation properties of turbulent premixed lean flames. In this study, a high-speed infrared camera was utilized to measure the planar radiation from turbulent premixed lean flames under different conditions. Time-dependent flame images were acquired and radiation statistics were calculated and compared to investigate the effects of equivalence ratio, heat release rate, hydrogen pilot flame rate, and co-flow rate on the radiation intensity …

The Role Of Surface Area In Catalytic Gasification Of Biomass, Elizabeth A. Wachs, Nitish Kumar, Indraneel Sircar, Prithviraja Basak, Jay P. Gore Phd

The Summer Undergraduate Research Fellowship (SURF) Symposium

Gasification of biomass has the potential to provide a carbon-negative source of liquid fuels. The current limited use of gasification is due in part to the high temperatures necessary to achieve high conversion levels. These temperatures can be lowered by the use of catalysts, but the mechanisms by which catalysts affect the reaction rate are not fully understood. Here, the structural component of potassium carbonate’s role in the gasification process was examined. Samples of pinewood sawdust were impregnated with potassium carbonate, then pyrolyzed with N2 in a fixed bed reactor at 750°C (heater thermocouple reading). Half of the char was …

Engineering Leadership Assessment Tool Profile, Karan Sharma, Monique Ross, Monica F. Cox

The Summer Undergraduate Research Fellowship (SURF) Symposium

Numerous studies have been conducted stressing the importance of developing the professional skillset of engineers. This need has been further highlighted by the Engineering Criteria 2000 and by the National Academy of Engineers (Kumar and Hsiao, 2007, p. 19). Having realised the need to develop the professional skillset of engineers such as leadership, interpersonal skills, teamwork and communication, universities have started incorporating methods to hone these skills in their courses. However in today’s competitive world, every practice needs to be assessed and measured for accountability and effectiveness. Engineering education is no exception to this rule. There needs to be a …

Investigation Of Fracture And Healing Behavior Of Thermoreversible Gels Via Oscillation Rheology, Krithika Subramaniam, Travis Thornell, Kendra Erk

The Summer Undergraduate Research Fellowship (SURF) Symposium

Thermoreversible gels have the unique ability to self-heal, or repair themselves, once they are fractured. They are physically cross-linked, thus providing them with the capability to reform their broken bonds as a function of temperature. The objective of this project is to determine the extent of the gels’ recovery. If self-healing does in fact occur, these gels can be applied in various industries, including medicine for drug delivery or paints and coatings. The tri-block polymer poly(methyl methacrylate)-poly(n-butyl acrylate)-poly(methyl methacrylate) (PMMA-PnBA-PMMA) was heated and stirred with 2-ethyl-1-hexanol to create a polymer gel. Through the use of a rheometer, a shear stress …

Simulating Nanoscale Optics In Photovoltaics With The S-Matrix Method, Dalton Chaffee, Xufeng Wang, Peter Bermel

The Summer Undergraduate Research Fellowship (SURF) Symposium

In the push to build high-efficiency solar cells with less materials usage, thin-film solar cells have attracted an increasing amount of interest. Thin films are particularly attractive if they could exhibit light trapping and photon recycling capabilities exceeding those of traditional wafer-based cells. Recent work by Alta Devices demonstrating a record single-junction efficiency of 28.8% with a gallium arsenide thin film cell shows the potential. However, most existing simulation tools do not handle these properties well -- particularly photon recycling. In this work, we develop an improved solar cell simulation tool to accurately predict thin-film performance. It is based on …

Preliminary Testing Of Plasma-Induced Combustion, Ahmed Thalib Razi, Carson Slabaugh, Robert Lucht

The Summer Undergraduate Research Fellowship (SURF) Symposium

Plasma-induced combustion (PIC) has been shown to improve the reliability, efficiency, and delay time of ignition in flight systems like augmentors and scramjets. These high-velocity systems are mostly used in military applications, and improvement may help commercial viability. To understand this chemical process, the concentration of radicals, particularly H radicals, must be tracked through the flame using laser diagnostics. This requires a steady source of plasma-assisted combustion to be secured and well-understood. A plasma torch flowing partially premixed air and methane was installed and successfully operated, and preliminary testing was carried out. Primarily it was observed that PIC created stable …

Synthesis And Thermoelectric Properties Of Cusbs2, Tianyue Gao, Haiyu Fang, Yue Wu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Copper antimony sulfide, CuSbS2 nanoparticles have a large potential of being a good thermoelectric material because they are made up of earth abundant elements. Thermoelectric materials can convert thermal energy into electricity, so that the wasted energy can be saved. Also, by using this earth abundant material, we can make thermoelectric materials much cheaper. The hypothesis of this study is that CuSbS2 could have a large Seebeck coefficient, one of the most important factors of thermoelectric materials, because of the complexity of its band structure. The other hypothesis is that thermal transport could be significantly suppressed through nanostructuring. There are …

Thermal Properties Of Soft Nanomaterials: Thermal Measurement Design, Yu Han, Meng Pan, Amy Marconnet, Collier Miers

The Summer Undergraduate Research Fellowship (SURF) Symposium

Soft materials like hydrogels have multiple tunable material properties because of their unique structures. Due to the ability to respond to stimuli like temperature or chemical environment, they have numerous applications in different fields like delivering drugs inside the human body and other medical uses. Details of the thermal transport mechanisms, as well as the overall thermal properties, are critical for a variety of applications. Multi-property measurements elucidate the underlying transport mechanisms in the soft materials. This research demonstrates a new methodology of measuring thermal properties of soft materials. This work uses the 3w method [1,2] for measuring the thermal …

Social Media Analytics Reporting Toolkit, Yuchen Cui, Junghoon Chae, David Ebert

The Summer Undergraduate Research Fellowship (SURF) Symposium

With the fast growth of social media services, vast amount of user-generated content with time-space stamps are produced everyday. Considerable amount of these data are publicly available online, some of which collectively convey information that are of interest to data analysts. Social media data are dynamic and unstructured by nature, which makes it very hard for analysts to efficiently and effectively retrieve useful information. Social Media Analytics Reporting Toolkit (SMART), a system developed at Purdue VACCINE lab, aims to support such analyzing. The current framework collects real-time Twitter messages and visualizes volume densities on a map. It uses Latent Dirichilet …

Comparison Of Thermal And Γ-Photon Induced Degradation In Polylactic Acid For Potential As A Solid-State Radiation Detector, Nathan M. Boyle, Alex Bakken, Rusi P. Taleyarkhan

The Summer Undergraduate Research Fellowship (SURF) Symposium

Degradation of the biopolymer Polylactic Acid, both thermally and through irradiation will cause physical changes in the material. These changes can be used in applications such as adhesives and sealants or in medical applications, but the primary focus of this study is for use as a solid-state radiation detector. A literature review shows that current research has been focused on thermal and γ-photon degradation in PLA but the physical characteristics such as melting temperature, latent heat of fusion, and composition of molecular bonds have not been compared in the same study. This study focuses on how thermal properties of PLA …

The Role Of Metal Oxide Layers In The Sensitivity Of Lactate Biosensors Subjected To Oxygen-Limited Conditions, Elizabeth Andreasen, Lia Stanciu, Aytekin Uzunoglu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Amperometric lactate biosensors are used to detect lactate concentration in blood and tissues, which is integral in identifying cyanide poisoning, septic shock, and athletic condition. The construction of lactate biosensors with high sensitivity, selectivity, and stability is imperative to diagnose and determine these medical conditions. Lactate detection is currently limited to oxygen-rich environments due to the fact that oxygen is a limiting factor in the lactate reaction. To circumvent this problem, researchers have developed mediators or alternate, oxygen-free enzymes to improve sensitivity. In our study, ceria (CeO₂) with high oxygen storage capacity (OSC) was introduced to the enzyme …

College Of Engineering News, Georgia Southern University

College of Engineering & Computing: News & Publications (2010-2023)

• Dr. Danda Rawat (EE) receives NSF grant

Pengaruh Berbagai Komposisi Kompos Dalam Tiga Jenis Media Pembibitan Terhadap Pertumbuhan Bibit Asparagus Dalam Polibeg, F. Kholifah, Tino Mutiarawati Onggo, Wawan Sutari

Jurnal Kultivasi

Asparagus seeding need suitable medium composition in order that seedlings can grow well and proper to be planted.The experiment aims to study the effect of different seedlings medium and various compost compositions within the medium on growth of asparagus seedlings planted in polybag.The experiment was conducted in research station of Agriculture Faculty, Universitas Padjadjaran, Jatinangor, Sumedang, located at 730 m above the sea level, conducted from May 2013 up to August 2013. A factorial randomized blocks design was used with four replications. The First factor was different seedlings medium, which consisted of three levels: rice husk, rice husk charcoal and …

A Mechanical Testing Methodology For Additive Manufacturing Processes, Sujitkumar Dongare, Todd E. Sparks, Joseph William Newkirk, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Most additive manufacturing processes are layer-by-layer deposition, thus its mechanical properties could be very different than those made from traditional manufacturing processes. This paper summarizes a mini-tensile testing methodology for additive manufacturing. Research concerning the tensile testing of metallic material has been conducted and test methods have been defined. It encompasses the methods for determination of yield strength, yield point elongation, tensile strength, elongation, and reduction of area. The study of positional variation and cooling-rate dependency in case of additive manufacturing proves to be expensive and time consuming with the full-size test specimens. Thus, this paper discussed a technique for …

Investigation Of Forged-Like Microstructure Produced By A Hybrid Manufacturing Process, Romy Francis, Joseph William Newkirk, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Laser Metal Deposition (LMD) is an additive manufacturing technique for manufacturing complex near net shaped components. The grain size of the typical deposition microstructure in case of Ti-6Al-4V can range between 100µm-600µm, which is much larger than that of forged-like microstructures. Friction Stir Processing (FSP) has been investigated as a method for surface modification to form refined microstructure at the surface of the Ti-6Al-4V components manufactured from the LMD method. Integration of FSP and LMD can greatly improve the product properties. Friction stir processing of the laser deposited Ti-6Al-4V deposits was performed and optimum processing parameters were obtained using this …

Thermographic Investigation Of Laser Metal Deposition, Sreekar Karnati, Todd E. Sparks, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Primitive stages of studies on and with additive manufacturing techniques popularly involve thin wall geometry. In the current effort attempts were made to capture various thermal aspects during deposition of a thin wall geometry. The thermo-graphic data was captured using a FLIR A615 infrared camera. Post processing using edge detection algorithms and image processing techniques, the geometric and thermal aspects of meltpool and tail of the meltpool were obtained. The effect of geometry and power on shape of the meltpool and its tail were obtained. The depositions of SS 316 with varying power. These observations were discussed and analyzed in …

Stereo Vision Based Hybrid Manufacturing Of Ti-6al-4v In Component Repair Process, Renwei Liu, Zhiyuang Wang, Todd E. Sparks, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Parts or products from high performance metal are very expensive, partly due to the processing complexities during manufacturing. Recent studies have indicated that hybrid processes of additive manufacturing and machining process can be used to repair titanium parts, thus extending the service life. In order to implement these methods automatically, it is necessary to obtain the spatial geometry information of component with defects to generate the tool path. The purpose of this paper is to summarize the research on hybrid manufacturing with stereo vision function which can be applied to the component repair process. Stereo vision is adopted to detect …

Investigation Of Sparse-Build Rapid Tooling By Fused Deposition Modeling, Osman Iyibilgin, Ming-Chuan Leu, Gregory Taylor, H. Li, K. Chandrashekhara

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper describes the investigation of sparse-build tooling by Fused Deposition Modeling (FDM®) aimed at rapid tooling with reduction in the amount of material. Sparse-build test coupons having ULTEM as the material and varying air gap (sparse spacing), wall thickness, and cap thickness were fabricated using the sparse and sparse-double dense build styles of the Stratasys Fortus machine. The strengths and moduli of these coupons were measured in compression and flexure tests. The strength/mass ratio and modulus/mass ratio were compared among the various coupons, as well as with solid coupons, to investigate the effects of the two build styles and …

In Vitro Assessment Of Laser Sintered Bioactive Glass Scaffolds With Different Pore Geometries, Krishna C. R. Kolan, Albin Thomas, Ming-Chuan Leu, Greg Hilmas

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The pore geometry of bioactive glass scaffolds intended for use in bone repair or replacement is one of the most important parameters that could determine the rate of bone regeneration. The pore geometry would also affect the mechanical properties of the scaffolds and their rate of degradation. Scaffolds with five different architectures, having ~50% porosity, were fabricated with silicate (13–93) and borate (13–93B3) based bioactive glasses using a laser sintering process. An established, late-osteoblasts/early-osteocytes cell line was used to perform cell proliferation tests on the scaffolds. The results indicated that the cells proliferate significantly more on the scaffolds which mimic …

Compact Verilog-A Modeling Of Silicon Traveling-Wave Modulator For Hybrid Cmos Photonic Circuit Design, Kehan Zhu, Vishal Saxena, Wan Kuang

Electrical and Computer Engineering Faculty Publications and Presentations

A compact Verilog-A model of silicon-based junction traveling-wave Mach-Zehnder modulator (MZM) is developed for hybrid CMOS and photonic system-level simulation in Cadence environment. Critical device functions such as the voltage dependent change of refractive index, small-signal RLGC parameters for the MZM arms are extracted from the photonic device characterization from OpSIS foundry. Thermo-optical coefficient is also considered in the model. Simulation results including electro-optic S21 is characterized for the phase modulator's bandwidth. Also, transient MZM operation with non-return to zero (NRZ) data transmission at 10 Gb/s and 20 Gb/s rates are demonstrated.

Our Decade In Space Plug-And-Play Avionics (Spa), James Lyke, Quinn Young, Jacob Christensen, David Anderson

Space Dynamics Laboratory Publications

Outline

• History / Background
• Overview of Plug-and-Play Technology
• Current Status
• Road Ahead

Towards Highly-Integrated Stereovideoscopy For In Vivo Surgical Robots, Jay Carlson

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

When compared to traditional surgery, laparoscopic procedures result in better patient outcomes: shorter recovery, reduced post-operative pain, and less trauma to incisioned tissue. Unfortunately, laparoscopic procedures require specialized training for surgeons, as these minimally-invasive procedures provide an operating environment that has limited dexterity and limited vision. Advanced surgical robotics platforms can make minimally-invasive techniques safer and easier for the surgeon to complete successfully. The most common type of surgical robotics platforms -- the laparoscopic robots -- accomplish this with multi-degree-of-freedom manipulators that are capable of a diversified set of movements when compared to traditional laparoscopic instruments. Also, these laparoscopic robots …

Optical Properties Of Nanostructured Dielectric Coatings, Brandon Giatti

Dissertations and Theses

Solar cells have extrinsic losses from a variety of sources which can be minimized by optimization of the design and fabrication processes. Reflection from the front surface is one such loss mechanism and has been managed in the past with the usage of planar antireflection coatings. While effective, these coatings are each limited to a single wavelength of light and do not account for varying incident angles of the incoming light source. Three-dimensional nanostructures have shown the ability to inhibit reflection for differing wavelengths and angles of incidence. Nanocones were modeled and show a broadband, multi-angled reflectance decrease due to …

Predicting Bicyclist Comfort In Protected Bike Lanes, Nicholas Mark-Andrew Foster

Dissertations and Theses

Long popular in northern Europe, protected bike lanes, also known as "cycle tracks" or "separated bike lanes," are seeing increased interest in the United States. One of the primary benefits of protected bike lanes is that they may provide a higher level of comfort than a standard bike lane that is only delineated by an inches-wide painted stripe. Several methods exist for quantifying the quality of service provided by a roadway for a bicyclist; however, many of these models do not consider protected bike lanes and of those that do, none are based on empirical data from the US. This …

Communication: Using Multiple Tethers To Stabilize Proteins On Surfaces, Brandon K. Loong, Thomas A. Knotts Iv

Faculty Publications

Protein surface interactions are important in many applications in biotechnology including protein arrays, but these technologies have not lived up to their transformative potential because it is difficult to attach proteins to surfaces in a manner that preserves function and theoretical understanding of the relevant phenomena remains limited. Here is reported the effect of using multiple tethers to attach a protein (lysozyme) to a surface and the effects on the structure and stability of the molecule. The simulations show how using two tethers can drastically change the folding mechanism such that a protein that is initially unstable and inactive when …

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering: News & Publications (2013-2023)

• Georgia Southern hosts prestigious National Science Foundation Research Experience for Undergraduates (REU) in Green- Engineered Transportation Technologies