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In this paper we investigate the problem of locating multiple non-cooperative radio frequency (RF) emitters using only received signal strength (RSS) data. We assume that the number of emitters is unknown and that individual emitters cannot be distinguished in the RSS data. Moreover, we assume that the environment in which the data has been collected has not been mapped or "fingerprinted" by the prior collection of RSS data. Our primary interest is the limiting resolution that can be obtained by this type of data, and the lowest power emitters that can be detected, as a function of noise level, sensor geometry, and other variables. We formulate the recovery problem as one of sparse approximation or compressed sensing, and investigate an appropriate recovery algorithm for this setting, and use it to illustrate our conclusions. We also include a reconstruction based on sampled data we collected, to illustrate the reasonableness of our parameter choices and conclusions., Comment: 14 pages, 8 figures

Pedagogical practices in electrical engineering education have been shifting away from teacher-centered learning during the past decade. An innovation that has enabled the adoption of inquiry-based and problem-based learning into the curriculum using experimentation coupled with simulation and analysis has been the development of portable oscilloscopes and other instruments that rely on tablet or laptop computers to perform some of the data processing and to act as the display. Faculty members at six institutions of higher learning have incorporated hands-on experimental activities into existing courses and/or developed new courses that take advantage of these new tools. Assessment data collected by these faculty members have demonstrated that the change towards student-centered learning facilitated by portable electronics increased student interest in electrical engineering, built student confidence in their ability to design circuits and systems, and supported the development of a deeper understanding of the theories that the students investigate or apply in the hands-on activities. A summary of the challenges that are faced in the different implementation models and a discussion of best practices are presented.

In cognitive radio systems, the available frequency bands are usually non-contiguous, which may cause impact on the spectrum utilization efficiency (SUE).When the receiver has a limited sampling capability, the aliasing phenomenon may cause interference among the signals at different frequency points, thus causing the loss of channel capacity. Information theoretic analysis is carried out to quantify the impact of spectrum non-contiguity on the channel capacity by analyzing the SUE. Beginning from the single sampler case, the analysis is also extended to the general case of sampler arrays. Numerical results are provided to answer several important questions on the impact of spectrum non-contiguity.

Unmanned aerial vehicles (UAVs) can be used to chase radio frequency (RF) emitters by sensing the signal sent out by the RF emitters. Meanwhile, the RF emitter can evade from the UAVs, thus forming a pursuit-evasion game. In contrast to traditional pursuit-evasion games, in which the players can always observe each other, the RF emitter can stop transmitting such that the UAVs lose the target. However, stopping the transmission also incurs cost to the RF emitter since it can no longer convey information to destinations. Hence, the RF emitter can take both continuous actions, i.e., the moving direction, and discrete actions, i.e., whether to stop transmission. Meanwhile, there are both discrete states, i.e., whether the RF transmitter is transmitting, and continuous states, i.e., the locations of UAVs and RF emitter, thus forming a hybrid system. We will study the game theoretic properties of this novel game and derive the optimal strategies for both parties under certain assumptions.

There is a need at Rose-Hulman Institute of Technology (RHIT) to increase the fundamental design, measurement, and laboratory skills for both Electrical Engineering and Biomedical Engineering students. Our project aims to improve students' design and practical problem solving skills, increase student interest in Electrical and Computer Engineering (ECE), and Biomedical Engineering (BE), and strengthen students' lab skills. In this project, we will be developing a web-based repository of worked circuit design examples; real world application demos of electrical circuits which visualize active, hands-on learning; and video-based tutorials for electrical circuit laboratory exercises.

Various methods for discovering the location of radio frequency (RF) emitters using unmanned aerial vehicles (UAVs) have been the focus of research over the past several years. Our work is aimed at determining the effectiveness of lowaccuracy direction finding (DF) technology to locate RF emissions using multiple UAVs. Small, commercial-off-theshelf (COTS) antenna systems can provide a rough estimate of an emitter's location within a 90 degree or 45 degree sector. Using these DF systems, a team of inexpensive UAVs can be deployed to collect low-accuracy data from multiple positions. A ground station would combine the information. In contrast to typical angle-of-arrival (AOA) methods, this unique technique does not require precise antenna arrays, complex hardware, or significant processing time to locate RF emissions. We present simulation results that show that accurate geolocation of emitters is possible with DF systems using only low accuracy (90-20 degrees) Angle of Arrival (AOA) information.

The Electrical Engineering curriculum is often coupled with extensive laboratory practice. The primary objectives of these laboratory experiences are to develop measurement and testing skills, draw relationships between classroom theory and real world applications and increase students' interest in the practice of the engineering profession. Traditionally, laboratory exercises that instruct students on the operation of instruments and basic measurement techniques are presented in a written format. For a novice student unfamiliar with the equipment, these written instructions can be confusing and frustrating. In this project, we are creating a web-based repository of video tutorials for electrical circuit laboratory exercises in a sophomore-level Introduction to Electrical Circuits class. We will study the effectiveness of the video-based lab tutorials on improving students' lab skills. In addition, this study will examine the students' preference between the video-based lab tutorials and text-based lab tutorials.

In various studies, it has been demonstrated that instructional media plays an important role in instructors' teaching and students' learning. The purpose of this study is to assess the students' preferences for different instructional media and the impact of different instructional media on the students' learning and course-related behavior in an undergraduate electrical circuit's course. The instructional media under study were: Computer-based PowerPoint presentation, whiteboard only, combination of PowerPoint and whiteboard and combination of printed handouts and whiteboard. Two schools participated in this study: Rose-Hulman Institute of Technology (RHIT), Terre Haute, IN and Qingdao University, Qingdao, P. R. China. At RHIT, two midterm exams and one final exam were used to assess the learning effectiveness of different instructional media. To understand the course related behavior, each of the instructors were asked to assess their students' behavior in terms of attendance, amount of classroom interaction, percent of homework completion and web logins. At the end of the quarter, a questionnaire was collected from participating students to measure their preference for the instructional media. The same questionnaire was given to the students at Qingdao University to study their preference for different instructional media.

Studies have demonstrated that instructional media play an important role in instructorspsila teaching and studentspsila learning. The purpose of this study is to assess the studentspsila preferences for different instructional media and the impact of different instructional media on the studentspsila learning and course-related behavior in an undergraduate electrical circuitpsilas course. The instructional media under study are: computer-based PowerPoint presentation, whiteboard only, combination of PowerPoint and whiteboard and combination of printed handouts and whiteboard. In this study, nine sections of Introduction to Electrical Circuits sections were taught by 6 instructors using different instructional media. All the instructors used a common syllabus, labs, homework, and tests. Two midterm exams and one final exam were used to assess the learning effectiveness of different instructional media. At the end of the quarter, a questionnaire was collected from participating students to measure their preference for the instructional media. To understand the course related behavior, each of the instructors were asked to assess their studentspsila behavior in terms of attendance, amount of classroom interaction, percent of homework completion and Web logins.

As digital ink technology continues to make an impact on the technical classroom, faculty members are exploring the different strategies for using this technology to improve student learning. The purpose of this panel is to demonstrate how faculty members are implementing this technology in engineering and science classrooms at three different institutions: Rose-Hulman Institute of Technology, University of Texas at Austin, and University of Vermont. The panel is designed to show both experienced pen computing users and those who are new to the field the different ways this versatile technology may be employed. In addition to the demonstrations, the presenters will discuss the pedagogical implications that result from the implementations. Faculty who are interested in both the pedagogy and assessment of pen-based computing in the classroom should find the session informative and useful.

This special session is organized to provide a highly interactive forum for a spirited exchange of varied ideas and teaching techniques between presenters and audience. Six presenters have been invited in advance by the session chairs with each presenter limited to 5 minutes and 3 slides followed by 3 minutes of discussion with the audience. Members of the audience are encouraged to bring a 1 paragraph summary for a random selection of up to three additional presenters. A 12 minute, informal exchange between all participants will follow the speakers. Under ideal conditions, the rapid, paced presentations and exchanges with the audience will make it difficult to distinguish between the presenters and the audience.

Dose is becoming increasingly important for computed tomography clinical practice. It is of general interest to understand the impact that system design can have on dose and image quality. This study addresses the effect of bowtie shape on the dose and contrast-to-noise across the field of view. Simulation of the CT acquisition is used to calculate the energy deposition throughout a numerical phantom for a set of relevant system operating parameters and bowtie shapes. Mean absorbed dose is calculated by summing over the phantom volume and is compared with other typical dose specifications. A more aggressive attenuation profile of the bowtie which offers higher attenuation in the periphery of the field of view can offer the benefit of lower dose but at the expense of reduced contrast-to-noise at the edge of the cross-sectional image.