Matching Items (155)
Description
The relationship between user experience, learning, and psychology is complex. There are many rules and concepts that guide experience design. It is likely that some of the guidance is valid whereas other guidance is not. This explores some of that guidance and evaluates how they are linked to learning. Do the guidance’s made 25, 50, 100 years ago still hold true today? Additionally, the psychological background behind the way someone holds memory is important. Knowing how information is stored and processed helps educators provide the best learning experience possible. With an eye toward perception and cognition, this paper examines the relevance of the various pieces of guidance. The results suggest that, overall, this guidance is still valid and valuable to current learning trends and designs. This suggests that user experience designers for education need to pay attention to the guidance provided by psychology when designing learning management systems, placing content in a course, and choosing which aesthetics to follow.
ContributorsLapujade, Lily Ann (Author) / Branaghan, Russell (Thesis director) / Roscoe, Rod (Committee member) / Human Systems Engineering (Contributor, Contributor) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Current technology does not allow for the full amount of power produced by solar arrays (PV) on spacecraft to be utilized. The arrays are designed with non-reconfigurable architectures and sent on fifteen to twenty year long missions. They cannot be changed once they are in space, so the arrays are designed for the end of life. Throughout their lifetime, solar arrays can degrade in power producing capabilities anywhere from 20% to 50%. Because there is such a drastic difference in the beginning and end of life power production, and because they cannot be reconfigured, a new design has been found necessary in order to increase power production. Reconfiguration allows the solar arrays to achieve maximum power producing capabilities at both the beginning and end of their lives. With the potential to increase power production by 50%, the reconfiguration design consists of a switching network to be able to utilize any combination of cells. The design for reconfiguration must meet the power requirements of the solar array. This thesis will explore different designs for reconfiguration, as well as possible switches for implementation. It will also review other methods to increase power production, as well as discuss future work in this field.
ContributorsJohnson, Everett Hope (Author) / Kitchen, Jennifer (Thesis director) / Ozev, Sule (Committee member) / School of International Letters and Cultures (Contributor) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Minimally invasive surgery is a surgical technique that is known for its reduced
patient recovery time. It is a surgical procedure done by using long reached tools and an
endoscopic camera to operate on the body though small incisions made near the point of
operation while viewing the live camera feed on a nearby display screen. Multiple camera
views are used in various industries such as surveillance and professional gaming to
allow users a spatial awareness advantage as to what is happening in the 3D space that is
presented to them on 2D displays. The concept has not effectively broken into the
medical industry yet. This thesis tests a multi-view camera system in which three cameras
are inserted into a laparoscopic surgical training box along with two surgical instruments,
to determine the system impact on spatial cognition, perceived cognitive workload, and
the overall time needed to complete the task, compared to one camera viewing the
traditional set up. The task is a non-medical task and is one of five typically used to train
surgeons’ motor skills when initially learning minimally invasive surgical procedures.
The task is a peg transfer and will be conducted by 30 people who are randomly assigned
to one of two conditions; one display and three displays. The results indicated that when
three displays were present the overall time initially using them to complete a task was
slower; the task was perceived to be completed more easily and with less strain; and
participants had a slightly higher performance rate.
patient recovery time. It is a surgical procedure done by using long reached tools and an
endoscopic camera to operate on the body though small incisions made near the point of
operation while viewing the live camera feed on a nearby display screen. Multiple camera
views are used in various industries such as surveillance and professional gaming to
allow users a spatial awareness advantage as to what is happening in the 3D space that is
presented to them on 2D displays. The concept has not effectively broken into the
medical industry yet. This thesis tests a multi-view camera system in which three cameras
are inserted into a laparoscopic surgical training box along with two surgical instruments,
to determine the system impact on spatial cognition, perceived cognitive workload, and
the overall time needed to complete the task, compared to one camera viewing the
traditional set up. The task is a non-medical task and is one of five typically used to train
surgeons’ motor skills when initially learning minimally invasive surgical procedures.
The task is a peg transfer and will be conducted by 30 people who are randomly assigned
to one of two conditions; one display and three displays. The results indicated that when
three displays were present the overall time initially using them to complete a task was
slower; the task was perceived to be completed more easily and with less strain; and
participants had a slightly higher performance rate.
ContributorsSchroll, Katelyn (Author) / Cooke, Nancy J. (Thesis advisor) / Chiou, Erin (Committee member) / Craig, Scotty (Committee member) / Arizona State University (Publisher)
Created2019
Description
Portable health diagnostic systems seek to perform medical grade diagnostics in non-ideal environments. This work details a robust fault tolerant portable health diagnostic design implemented in hardware, firmware and software for the detectionof HPV in low-income countries. The device under device under test (DUT) is a fluorescence based lateral flow assay (LFA) point-of-care (POC) device. This work’s contributions are: firmware and software development, calibration routine implementation, device performance characterization and a proposed method of in-software fault detection. Firmware was refactored from the original implementation of the POC fluorescence reader to expose an application programming interface (API) via USB. Companion software available for desktop environments (Windows, Mac and Linux) was created to interface with this firmware API and conduct macro level routines to request and receive fluorescence data while presenting a user-friendly interface to clinical technicians. Lastly, an environmental chamber was constructed to conduct sequential diagnostic reads in order to observe sensor drift and other deviations that might present themselves in real-world usage. The results from these evaluations show a standard deviation of less than 1% in fluorescence readings in nominal temperature environments (approx. 25C) suggesting that this system will have a favorable signal-to-noise (SNR) ratio in such a setting. In non-ideal over heated environments (≥38C), the evaluation results showed performance degradation with standard deviations as large as 15%.
ContributorsLue Sang, Christopher David (Author) / Blain Christen, Jennifer M (Thesis advisor) / Ozev, Sule (Committee member) / Goryll, Michael (Committee member) / Raupp, Gregory (Committee member) / Arizona State University (Publisher)
Created2022
Description
The world has seen a revolution in cellular communication with the advent of 5G, which enables gigabits per second data speed with low latency, massive capacity, and increased availability. Complex modulated signals are used in these moderncommunication systems to achieve high spectral efficiency, and these signals exhibit high peak to average power ratios (PAPR). Design of cellular infrastructure hardware to support these complex signals therefore becomes challenging, as the transmitter’s radio frequency power amplifier (RF PA) needs to remain highly efficient at both peak and backed off power conditions. Additionally, these PAs should exhibit high linearity and support continually increasing bandwidths. Many advanced PA configurations exhibit high efficiency for processing legacy communications signals. Some of the most popular architectures are Envelope Elimination and Restoration (EER), Envelope Tracking (ET), Linear Amplification using Non-linear Component (LINC), Doherty Power Amplifiers (DPA), and Polar Transmitters. Among these techniques,
the DPA is the most widely used architecture for base-station applications because of its simple configuration and ability to be linearized using simple digital pre-distortion (DPD) algorithms. To support the cellular infrastructure needs of 5G and beyond, RF PAs, specifically DPA architectures, must be further enhanced to support broader bandwidths as well as smaller form-factors with higher levels of integration. The following four novel works are presented in this dissertation to support RF PA requirements for future cellular infrastructure:
1. A mathematical analysis to analyze the effects of non-linear parasitic capacitance (Cds) on the operation of continuous class-F (CCF) mode power amplifiers and identify their optimum operating range for high power and efficiency.
2. A methodology to incorporate a class-J harmonic trapping network inside the PA package by considering the effect of non-linear Cds, thus reducing the DPA footprint while achieving high RF performance.
3. A novel method of synthesizing the DPA’s output combining network (OCN) to realize an integrated two-stage integrated LDMOS asymmetric DPA.
4. A novel extended back-off efficiency range DPA architecture that engineers the mutual interaction between combining load and peaking off-state impedance. The theory and architecture are verified through a GaN-based DPA design.
ContributorsAhmed, Maruf Newaz (Author) / Kitchen, Jennifer (Thesis advisor) / Aberle, James (Committee member) / Bakkaloglu, Bertan (Committee member) / Ozev, Sule (Committee member) / Arizona State University (Publisher)
Created2022
Description
Team communication facilitates team coordination strategies and situations, and how teammates perceive one another. In human-machine teams, these perceptions affect how people trust and anthropomorphize their machine counterparts, which in turn affects future team communication, forming a feedback loop. This thesis investigates how personifying and objectifying contents in human-machine team communication relate to team performance and perceptions in a simulated remotely piloted aircraft system task environment. A total of 46 participants grouped into teams of two were assigned unique roles and teamed with a synthetic pilot agent that in reality was a trained confederate following a script. Quantities of verbal personifications and objectifications were compared to questionnaire responses about participants’ perceived trust and anthropomorphism of the synthetic pilot, as well as team performance. It was hypothesized that verbal personifications would positively correlate with reflective trust, anthropomorphism, and team performance, and that verbal objectifications would negatively correlate with the same measures. It was also predicted that verbal personifications would decrease over time as human teammates interact more with the machine teammate, and that verbal objectifications would increase. Verbal personifications were not found to be correlated with trust and anthropomorphism outside of perceptions related to gender, albeit patterns of change in the navigator’s personifications coincided with a co-calibration of trust among the navigator and the photographer. Results supported the prediction that verbal objectifications are negatively correlated with trust and anthropomorphism of a teammate. Significant relationships between verbal personifications and objectifications and team performance were not found. This study provides support to the notion that people verbally personify machines to ease communication when necessary, and that the same processes that underlie tendencies to personify machines may be reciprocally related to those that influence team trust. Overall, this study provides evidence that personifying and objectifying language in human-machine team communication is a viable candidate for measuring the perceptions and states of teams, even in highly restricted communication environments.
ContributorsCohen, Myke C. (Author) / Cooke, Nancy J. (Thesis advisor) / Chiou, Erin K. (Committee member) / Amazeen, Polemnia G. (Committee member) / Arizona State University (Publisher)
Created2022
Description
This work presents two balanced power amplifier (PA) architectures, one at X-band and the other at K-band. The presented balanced PAs are designed for use in small satellite and cube satellite applications.The presented X-band PA employs wideband hybrid couplers to split input power to two commercial off-the-shelf (COTS) Gallium Nitride (GaN) monolithic microwave integrated circuit (MMIC) PAs and combine their output powers. The presented X-band balanced PA manufactured on a Rogers 4003C substrate yields increased small signal gain and saturated output power under continuous wave (CW) operation compared to the single MMIC PA used in the design under pulsed operation. The presented PA operates from 7.5 GHz to 11.5 GHz, has a maximum small signal gain of 36.3 dB, a maximum saturated power out of 40.0 dBm, and a maximum power added efficiency (PAE) of 38%.
Both a Wilkinson and a Gysel splitter and combiner are designed for use at K-band and their performance is compared. The presented K-band balanced PA uses Gysel power dividers and combiners with a GaN MMIC PA that is soon to be released in production.
ContributorsPearson, Katherine Elizabeth (Author) / Kitchen, Jennifer (Thesis advisor) / Bakkaloglu, Bertan (Committee member) / Ozev, Sule (Committee member) / Arizona State University (Publisher)
Created2023
Description
It is difficult to imagine a society that does not utilize teams. At the same time, teams need to evolve to meet today’s challenges of the ever-increasing proliferation of data and complexity. It may be useful to add artificial intelligent (AI) agents to team up with humans. Then, as AI agents are integrated into the team, the first study asks what roles can AI agents take? The first study investigates this issue by asking whether an AI agent can take the role of a facilitator and in turn, improve planning outcomes by facilitating team processes. Results indicate that the human facilitator was significantly better than the AI facilitator at reducing cognitive biases such as groupthink, anchoring, and information pooling, as well as increasing decision quality and score. Additionally, participants viewed the AI facilitator negatively and ignored its inputs compared to the human facilitator. Yet, participants in the AI Facilitator condition performed significantly better than participants in the No Facilitator condition, illustrating that having an AI facilitator was better than having no facilitator at all. The second study explores whether artificial social intelligence (ASI) agents can take the role of advisors and subsequently improve team processes and mission outcome during a simulated search-and-rescue mission. The results of this study indicate that although ASI advisors can successfully advise teams, they also use a significantly greater number of taskwork interventions than teamwork interventions. Additionally, this study served to identify what the ASI advisors got right compared to the human advisor and vice versa. Implications and future directions are discussed.
ContributorsBuchanan, Verica (Author) / Cooke, Nancy J. (Thesis advisor) / Gutzwiller, Robert S. (Committee member) / Roscoe, Rod D. (Committee member) / Arizona State University (Publisher)
Created2023
Description
Impedance is one of the fundamental properties of electrical components, materials, and waves. Therefore, impedance measurement and monitoring have a wide range of applications. The multi-port technique is a natural candidate for impedance measurement and monitoring due to its low overhead and ease of implementation for Built-in Self-Test (BIST) applications. The multi-port technique can measure complex reflection coefficients, thus impedance, by using scalar measurements provided by the power detectors. These power detectors are strategically placed on different points (ports) of a passive network to produce unique solution. Impedance measurement and monitoring is readily deployed on mobile phone radio-frequency (RF) front ends, and are combined with antenna tuners to boost the signal reception capabilities of phones. These sensors also can be used in self-healing circuits to improve their yield and performance under process, voltage, and temperature variations. Even though, this work is preliminary interested in low-overhead impedance measurement for RF circuit applications, the proposed methods can be used in a wide variety of metrology applications where impedance measurements are already used. Some examples of these applications include determining material properties, plasma generation, and moisture detection. Additionally, multi-port applications extend beyond the impedance measurement. There are applications where multi-ports are used as receivers for communication systems, RADARs, and remote sensing applications. The multi-port technique generally requires a careful design of the testing structure to produce a unique solution from power detector measurements. It also requires the use of nonlinear solvers during calibration, and depending on calibration procedure, measurement. The use of nonlinear solvers generates issues for convergence, computational complexity, and resources needed for carrying out calibrations and measurements in a timely manner. In this work, using periodic structures, a structure where a circuit block repeats itself, for multi-port measurements is proposed. The periodic structures introduce a new constraint that simplifies the multi-port theory and leads to an explicit calibration and measurement procedure. Unlike the existing calibration procedures which require at least five loads and various constraints on the load for explicit solution, the proposed method can use three loads for calibration. Multi-ports built with periodic structures will always produce a unique measurement result. This leads to increased bandwidth of operation and simplifies design procedure. The efficacy of the method demonstrated in two embodiments.
In the first embodiment, a multi-port is directly embedded into a matching network to measure impedance of the load.
In the second embodiment, periodic structures are used to compare two loads without requiring any calibration.
ContributorsAvci, Muslum Emir (Author) / Ozev, Sule (Thesis advisor) / Bakkaloglu, Bertan (Committee member) / Kitchen, Jennifer (Committee member) / Trichopoulos, Georgios (Committee member) / Arizona State University (Publisher)
Created2023
Description
The implementation of chatbots in customer service is widely prevalent in today’s world with insufficient research to appropriately refine all of their conversational abilities. Chatbots are favored for their ability to handle simple and typical requests made by users, but chatbots have proven to be prone to conversational breakdowns. The study researched how the use of repair strategies to combat conversational breakdowns in a simple versus complex task setting affected user experience. Thirty participants were collected and organized into six different groups in a two by three between subjects factorial design. Participants were assigned one of two tasks (simple or complex) and one of three repair strategies (repeat, confirmation, or options). A Wizard-of-Oz approach was used to simulate a chatbot that participants interacted with to complete a task in a hypothetical setting. Participants completed the task with this researcher-controlled chatbot as it intentionally failed the conversation multiple times, only to repair it with a repair strategy. Participants recorded their user experience regarding the chatbot afterwards. An Analysis of Covariance statistical test was run with task duration being a covariate variable. Findings indicate that the simple task difficulty was significant in improving the user experience that participants recorded whereas the particular repair strategy had no effect on the user experience. This indicates that simpler tasks lead to improved positive user experience and the more time that is spent on a task, the less positive the user experience. Overall, results associated with the effects of task difficulty and repair strategies on user experience were only partially consistent with previous literature.
ContributorsRios, Aaron (Author) / Cooke, Nancy J. (Thesis advisor) / Gutzwiller, Robert S. (Committee member) / Chiou, Erin K. (Committee member) / Arizona State University (Publisher)
Created2022