Matching Items (152)
Description
Gathering and managing software requirements, known as Requirement Engineering (RE), is a significant and basic step during the Software Development Life Cycle (SDLC). Any error or defect during the RE step will propagate to further steps of SDLC and resolving it will be more costly than any defect in other steps. In order to produce better quality software, the requirements have to be free of any defects. Verification and Validation (V&V;) of requirements are performed to improve their quality, by performing the V&V; process on the Software Requirement Specification (SRS) document. V&V; of the software requirements focused to a specific domain helps in improving quality. A large database of software requirements from software projects of different domains is created. Software requirements from commercial applications are focus of this project; other domains embedded, mobile, E-commerce, etc. can be the focus of future efforts. The V&V; is done to inspect the requirements and improve the quality. Inspections are done to detect defects in the requirements and three approaches for inspection of software requirements are discussed; ad-hoc techniques, checklists, and scenario-based techniques. A more systematic domain-specific technique is presented for performing V&V; of requirements.
ContributorsChughtai, Rehman (Author) / Ghazarian, Arbi (Thesis advisor) / Bansal, Ajay (Committee member) / Millard, Bruce (Committee member) / Arizona State University (Publisher)
Created2012
Description
The field of flexible displays and electronics gained a big momentum within the recent years due to their ruggedness, thinness, and flexibility as well as low cost large area manufacturability. Amorphous silicon has been the dominant material used in the thin film transistor industry which could only utilize it as N type thin film transistors (TFT). Amorphous silicon is an unstable material for low temperature manufacturing process and having only one kind of transistor means high power consumption for circuit operations. This thesis covers the three major researches done on flexible TFTs and flexible electronic circuits. First the characterization of both amorphous silicon TFTs and newly emerging mixed oxide TFTs were performed and the stability of these two materials is compared. During the research, both TFTs were stress tested under various biasing conditions and the threshold voltage was extracted to observe the shift in the threshold which shows the degradation of the material. Secondly, the design of the first flexible CMOS TFTs and CMOS gates were covered. The circuits were built using both inorganic and organic components (for nMOS and pMOS transistors respectively) and functionality tests were performed on basic gates like inverter, NAND and NOR gates and the working results are documented. Thirdly, a novel large area sensor structure is demonstrated under the Electronic Textile project section. This project is based on the concept that all the flexible electronics are flexible in only one direction and can not be used for conforming irregular shaped objects or create an electronic cloth for various applications like display or sensing. A laser detector sensor array is designed for proof of concept and is laid in strips that can be cut after manufacturing and weaved to each other to create a real flexible electronic textile. The circuit designed uses a unique architecture that pushes the data in a single line and reads the data from the same line and compares the signal to the original state to determine a sensor excitation. This architecture enables 2 dimensional addressing through an external controller while eliminating the need for 2 dimensional active matrix style electrical connections between the fibers.
ContributorsKaftanoglu, Korhan (Author) / Allee, David R. (Thesis advisor) / Kozicki, Michael N (Committee member) / Holbert, Keith E. (Committee member) / Kaminski, Jann P (Committee member) / Arizona State University (Publisher)
Created2012
Description
Renewable energy has been a very hot topic in recent years due to the traditional energy crisis. Incentives that encourage the renewables have been established all over the world. Ordinary homeowners are also seeking ways to exploit renewable energy. In this thesis, residential PV system, wind turbine system and a hybrid wind/solar system are all investigated. The solar energy received by the PV panels varies with many factors. The most essential one is the irradiance. As the PV panel been installed towards different orientations, the incident insolation received by the panel also will be different. The differing insolation corresponds to the different angles between the irradiance and the panel throughout the day. The result shows that for PV panels in the northern hemisphere, the ones facing south obtain the highest level insolation and thus generate the most electricity. However, with the two different electricity rate plans, flat rate plan and TOU (time of use) plan, the value of electricity that PV generates is different. For wind energy, the wind speed is the most significant variable to determine the generation of a wind turbine. Unlike solar energy, wind energy is much more regionally dependent. Wind resources vary between very close locations. As expected, the result shows that, larger wind speed leads to more electricity generation and thus shorter payback period. For the PV/wind hybrid system, two real cases are analyzed for Altamont and Midhill, CA. In this part, the impact of incentives, system cost and system size are considered. With a hybrid system, homeowners may choose different size combinations between PV and wind turbines. It turns out that for these two locations, the system with larger PV output always achieve a shorter payback period due to the lower cost. Even though, for a longer term, the system with a larger wind turbine in locations with excellent wind resources may lead to higher return on investment. Meanwhile, impacts of both wind and solar incentives (mainly utility rebates) are analyzed. At last, effects of the cost of both renewables are performed.
ContributorsAn, Wen (Author) / Holbert, Keith E. (Thesis advisor) / Karady, George G. (Committee member) / Tylavsky, Daniel (Committee member) / Arizona State University (Publisher)
Created2012
Description
In this thesis, an issue is post at the beginning, that there is limited experience in connecting a battery analytical model with a battery circuit model. Then it describes the process of creating a new battery circuit model which is referred to as the kinetic battery model. During this process, a new general equation is derived. The original equation in the kinetic battery model is only valid at a constant current rate, while the new equation can be used for not only constant current but also linear or nonlinear current. Following the new equation, a circuit representation is built based on the kinetic battery model. Then, by matching the two sets of differential equations of the two models together, the ability to connect the analytical model with the battery circuit model is found. To verify the new battery circuit model is built correctly, the new circuit model is implemented into PSpice simulation software to test the charging performance with constant current, and Matlab/Simulink is also employed to simulate a realistic battery charging process with two-stage charging method. The results have shown the new circuit model is available to be used in realistic scenarios. And because the kinetic battery model can describe different types of rechargeable batteries, the new circuit model is also capable to be used for various battery types.
ContributorsKong, Dexinghui (Author) / Holbert, Keith E. (Thesis advisor) / Karady, George G. (Committee member) / Ayyanar, Raja (Committee member) / Arizona State University (Publisher)
Created2012
Description
Power generation in remote isolated places is a tough problem. Presently, a common source for remote generation is diesel. However, diesel generation is costly and environmental unfriendly. It is promising to replace the diesel generation with some clean and economical generation sources. The concept of renewable generation offers a solution to remote generation. This thesis focuses on evaluation of renewable generation penetration in the remote isolated grid. A small town named Coober Pedy in South Australia is set as an example. The first task is to build the stochastic models of solar irradiation and wind speed based on the local historical data. With the stochastic models, generation fluctuations and generation planning are further discussed. Fluctuation analysis gives an evaluation of storage unit size and costs. Generation planning aims at finding the relationships between penetration level and costs under constraint of energy sufficiency. The results of this study provide the best penetration level that makes the minimum energy costs. In the case of Coober Pedy, cases of wind and photovoltaic penetrations are studied. The additional renewable sources and suspended diesel generation change the electricity costs. Results show that in remote isolated grid, compared to diesel generation, renewable generation can lower the energy costs.
ContributorsZhu, Yujia (Author) / Holbert, Keith E. (Thesis advisor) / Karady, George G. (Committee member) / Tylavsky, Daniel J (Committee member) / Arizona State University (Publisher)
Created2012
Description
This undergraduate thesis explores the efficacy of developing a translator generator in the Prolog programming language using Lexical Functional Grammars. A bidirectional machine translator between English and Hungarian, developed as a proof-of-concept case study, is discussed and assessed. The benefits and drawbacks of this approach as generalized to Machine Translation systems are also discussed, along with possible areas of future work.
ContributorsLane, Ryan Andrew (Author) / Bansal, Ajay (Thesis director) / Bansal, Srividya (Committee member) / Barrett, The Honors College (Contributor)
Created2015-05
Description
Recently, electric and magnetic field sensing has come of interest to the military for a variety of applications, including imaging circuitry and detecting explosive devices. This thesis describes research at the ASU's Flexible Electronics and Display Center (FEDC) towards the development of a flexible electric and magnetic field imaging blanket. D-dot sensors, which detect changes in electric flux, were chosen for electric field sensing, and a single D-dot sensor in combination with a lock-in amplifier was used to detect individuals passing through an oscillating electric field. This was then developed into a 1 x 16 array of D-dot sensors used to image the field generated by two parallel wires. After the fabrication of a two-dimensional array, it was discovered that commercial field effect transistors did not have a high enough off-resistance to isolate the sensor form the column line. Three alternative solutions were proposed. The first was a one-dimensional array combined with a mechanical stepper to move the array across the E-field pattern. The second was a 1 x 16 strip detector combined with the techniques of computed tomography to reconstruct the image of the field. Such techniques include filtered back projection and algebraic iterative reconstruction (AIR). Lastly, an array of D-dot sensors was fabricated on a flexible substrate, enabled by the high off-resistance of the thin film transistors produced by the FEDC. The research on magnetic field imaging began with a feasibility study of three different types of magnetic field sensors: planar spiral inductors, Hall effect sensors, and giant magnetoresistance (GMR). An experimental array of these sensors was designed and fabricated, and the sensors were used to image the fringe fields of a Helmholtz coil. Furthermore, combining the inductors with the other two types of sensors resulted in three-dimensional sensors. From these measurements, it was determined that planar spiral inductors and Hall effect sensors are best suited for future imaging arrays.
ContributorsLarsen, Brett William (Author) / Allee, David (Thesis director) / Papandreou-Suppappola, Antonia (Committee member) / Barrett, The Honors College (Contributor) / Department of Physics (Contributor) / Electrical Engineering Program (Contributor)
Created2015-05
DescriptionThis is a project to create an electric field sensing system which is fully portable. This system should provide accurate electric field readings from transmission lines allowing abstraction to find the voltage on the transmission line.
ContributorsScowen, Kegan (Co-author) / Vora, Sandeep (Co-author) / Ye, Weidong (Co-author) / Sciacca, Jacob (Co-author) / Allee, David (Thesis director) / Karady, George (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Electrical Engineering Program (Contributor)
Created2014-12
Description
Acetaminophen, commonly found in Tylenol and other over the counter (OTC) pharmaceuticals, was electrochemically characterized on custom made, flexible, screen printed electrodes (SPEs) to serve as a model target pharmaceutical found in flowing water lines. Carbon, silver/silver chloride, and insulator paste inks were printed onto polyethylene naphthalateolyester (PEN) using custom made stencils for a 4x1 array of 3-electrode electrochemical cells. Cyclic voltammetry was performed to find the electrical potential corresponding to the greatest current response and the experiments were conducted using amperometric current-time mode (AMP*i-t). The physical limitations of SPEs as well as the detection limitations of the target, such as pH and temperature were tested. A concentration gradient of the target was fitted with a linear curve (R2 0.99), and a lower limit of detection of 14.5 μM. It was also found that both pH and temperature affect the current produced by acetaminophen at a fixed concentration, and that the sensors can detect target in a continuous flow. A flow apparatus consisting of an inlet and effluent pipe served as the flow model into which a rolled up flexible electrode array was inserted. The broader goal of this research is to develop a highly sensitive electrode array on flexible substrates which can detect multiple targets simultaneously. Acetaminophen was chosen due to its electro-active properties and its presence in most public water lines in the United States.
ContributorsMaxwell, Stephanie Ann (Author) / LaBelle, Jeffrey (Thesis director) / Allee, David (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
NGExtract 2 is a complete transistor (MOSFET) parameter extraction solution based upon the original computer program NGExtract by Rahul Shringarpure written in February 2007. NGExtract 2 is written in Java and based around the circuit simulator NGSpice. The goal of the program is to be used to produce accurate transistor models based around real-world transistor data. The program contains numerous improvements to the original program:
• Completely rewritten with performance and usability in mind
• Cross-Platform vs. Linux Only
• Simple installation procedure vs. compilation and manual library configuration
• Self-contained, single file runtime
• Particle Swarm Optimization routine
NGExtract 2 works by plotting the Ids vs. Vds and Ids vs. Vgs curves of a simulation model and the measured, real-world data. The user can adjust model parameters and re-simulate to attempt to match the curves. The included Particle Swarm Optimization routine attempts to automate this process by iteratively attempting to improve a solution by measuring its sum-squared error against the real-world data that the user has provided.
• Completely rewritten with performance and usability in mind
• Cross-Platform vs. Linux Only
• Simple installation procedure vs. compilation and manual library configuration
• Self-contained, single file runtime
• Particle Swarm Optimization routine
NGExtract 2 works by plotting the Ids vs. Vds and Ids vs. Vgs curves of a simulation model and the measured, real-world data. The user can adjust model parameters and re-simulate to attempt to match the curves. The included Particle Swarm Optimization routine attempts to automate this process by iteratively attempting to improve a solution by measuring its sum-squared error against the real-world data that the user has provided.
ContributorsVetrano, Michael Thomas (Author) / Allee, David (Thesis director) / Gorur, Ravi (Committee member) / Bakkaloglu, Bertan (Committee member) / Barrett, The Honors College (Contributor) / Computer Science and Engineering Program (Contributor)
Created2013-05