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Full-Text Articles in Engineering
Near-Optimal Control Of Switched Systems With Continuous-Time Dynamics Using Approximate Dynamic Programming, Tohid Sardarmehni
Near-Optimal Control Of Switched Systems With Continuous-Time Dynamics Using Approximate Dynamic Programming, Tohid Sardarmehni
Mechanical Engineering Research Theses and Dissertations
Optimal control is a control method which provides inputs that minimize a performance index subject to state or input constraints [58]. The existing solutions for finding the exact optimal control solution such as Pontryagin’s minimum principle and dynamic programming suffer from curse of dimensionality in high order dynamical systems. One remedy for this problem is finding near optimal solution instead of the exact optimal solution to avoid curse of dimensionality [31]. A method for finding the approximate optimal solution is through Approximate Dynamic Programming (ADP) methods which are discussed in the subsequent chapters.
In this dissertation, optimal switching in switched …
Circularly Polarized Two-Dimensional Microstrip Standing-Wave Array Antenna, Yang Fan
Circularly Polarized Two-Dimensional Microstrip Standing-Wave Array Antenna, Yang Fan
Electrical Engineering Theses and Dissertations
This dissertation reviews current designs of single-fed circularly polarized microstrip antennas and proposes a novel design concept with improved performance. The structure is similar to a regular microstrip patch antenna and the design procedure is relatively simple. By extending this SF scheme to an array structure based on the standing-wave array concept, a novel circular polarized array antenna can be realized by using one SF CP patch with standing-wave feeding networks. The standing-wave array antenna developed at SMU has a low-profile planar configuration and a simple feeding network structure and thus can be fabricated easily and cheaply with relatively high …
A Low Power High Speed Mobile Memory I/O Interface Using Reconfigurable Multi-Band Multi-Modulation Signaling, Yue Yu
Electrical Engineering Theses and Dissertations
This research mainly focuses on the design of a novel memory I/O interface with high bandwidth and high energy-efficient for mobile computing systems in order to dramatically enhance the circuit and system bandwidth and power efficiency. The proposed memory I/O interface, exploiting multi-modulation and multi-band signaling, is capable of supporting simultaneous bidirectional data transition of 4 separate data streams across a single-ended off-chip transmission line to achieve both high speed data rate and low power consumption. This multi-band multi-modulation interface (MMI) consists of multiple RF-band transceivers which utilize ASK modulation, and baseband transceivers which utilize 4-PAM modulation to increase the …
Spatial Division Multiplexing Using Ince-Gaussian Beams, Sahil Sakpal
Spatial Division Multiplexing Using Ince-Gaussian Beams, Sahil Sakpal
Electrical Engineering Theses and Dissertations
In space division multiplexing (SDM) the spatial modes of a multimode optical fiber are used as individual data channels. SDM gives another degree of freedom over wavelength for increasing data transmission rates. As a result, SDM is a potential solution for more than 400Gbit/s requirements in data centers where scaling data transmission rates with parallel single mode optical fibers is currently ubiquitous. However, due to mode coupling, i.e., spatial modes exchange of power, SDM may require multiple inputs multiple output digital signal processing (MIMO-DSP) to mitigate resulting mode crosstalk, the cost and complexity of which may be prohibited in data …
Securing Database Users From The Threat Of Sql Injection Attacks, Nisharg Shah
Securing Database Users From The Threat Of Sql Injection Attacks, Nisharg Shah
Electrical Engineering Theses and Dissertations
In the 21st century, there has been a significant rise in dependency on the Internet for daily activities. Web applications such as online banking, web-based emails, social networking, and many more services have become an instant means of communication. These web applications and the data to which they have access are often targeted using malicious attacks, including SQL (Structured Query Language) Injection Attacks (from now on referenced as SQLIAs), which may cause serious damage. In particular, attackers use SQLIAs to target interactive web applications that incorporate database services. In a SQLIA, an attacker can insert malicious SQL code as …