In this innovative practice work-in-progress paper, enrollment data from five institutions was used to examine equity in undergraduate research through Vertically Integrated Projects (VIP) programs. VIP is a model for...
详细信息
ISBN:
(纸本)9798350336429
In this innovative practice work-in-progress paper, enrollment data from five institutions was used to examine equity in undergraduate research through Vertically Integrated Projects (VIP) programs. VIP is a model for undergraduate research in which large student teams are embedded in faculty-driven projects. The American Association of Colleges and Universities recognizes undergraduate research as a high-impact experience, associated with higher graduation rates and greater learning gains in college. Participation in multiple high-impact experiences yields cumulative gains to students from all backgrounds, and compensatory gains for minoritized and marginalized students. Nationally however, minoritized students, first-generation college students, and transfer students participate in undergraduate research at lower rates than their peers. In this study, VIP enrollments at five institutions (N = 6,651 over two semesters) were compared to demographics of the institutions to determine the degree to which programs achieved equity among historically underserved minorities, transfer students, first-generation college students, and by gender. Analysis accounted for demographics and level of participation of the academic units involved, comparing enrollments with what would be expected under equitable enrollment. Analyses were done for each institution and across the pooled sample. By institution, equity across categories varied. Across the pooled sample, results show small effects sizes for status as a historically underserved minority, very small effect sizes for first-generation students and transfer students, and slightly higher participation among women than men. The large-scale nature of VIP teams enables institutions to scale-up their undergraduate research offerings. This paper begins answering the question of whether this scaling increases access for marginalized populations, and the results are encouraging. The paper is a work-in-progress, because data needs to be
Sags and swells are types of power quality disturbances that involve fluctuations in voltage. Sags are decreases in a voltage’s magnitude while swells are increases in a voltage’s magnitude. There are a number of di...
Sags and swells are types of power quality disturbances that involve fluctuations in voltage. Sags are decreases in a voltage’s magnitude while swells are increases in a voltage’s magnitude. There are a number of different techniques to identify and classify these power quality disturbances, however in an industrial setting power utilities typically employ the use of the CBEMA and ITIC curves to classify the power quality disturbances they encounter. The CBEMA and ITIC curves utilize RMS voltage to denote whether a disturbance is expected to impact the system it occurs on, however there are a number of ambiguities surrounding the use of both curves. One such ambiguity is the lack of specification surrounding the window size used to calculate RMS values. This paper proposes MATLAB scripts that can synthesize waveforms with sags and swells according to a variety of user-defined parameters and provide their RMS voltages. This paper also presents a MATLAB function that can plot the RMS voltage magnitude and durations of transient events onto the ITIC curve. This paper explores the effect of varying the window size used to calculate RMS voltage for each disturbance across different parameters. Moreover, the paper presents an analysis of the RMS voltage of a real-world voltage sag in a three-phase system.
Radio frequency energy harvesting has attracted considerable interest as a technique of enabling self-powered wireless networks. This technique faces several challenges, such as the receiving and the rectifying module...
详细信息
This paper demonstrates the seamless fabrication of optoelectronic memory by integrating HfSe 2 as a charge-trapping layer in a MOS memory structure. Through a spin coating technique, solution-processable HfSe 2 fla...
This paper demonstrates the seamless fabrication of optoelectronic memory by integrating HfSe 2 as a charge-trapping layer in a MOS memory structure. Through a spin coating technique, solution-processable HfSe 2 flakes with average thicknesses of 2 nm were deposited between the tunneling and blocking oxide layers. The charge-trapping material distribution and thickness were explored by Atomic Force Microscopy and X-ray Diffraction Spectroscopy. The electrical characterization of MOS memory revealed a memory window of 5.5 Volts under ±16 Volts biasing. Furthermore, the memory endurance exceeds 10 4 electricalprogramming and erasing cycles. The retention test performed at room temperature showed that the memory device is expected to lose only 10% of the stored charges after 10 years. Under light stimuli (405nm wavelength and output power ~ 20 mW) with electrical readout voltage, the MOS memory showed an increase in the memory window from 5.5 Volts to 6.5 Volts.
Recently, techniques for fabricating micro-sized deep ultraviolet light-emitting diodes (DUV LEDs) have been gaining attention. In this work, we propose a selective thermal oxidation (STO) process to fabricate ultra-s...
详细信息
Recently, techniques for fabricating micro-sized deep ultraviolet light-emitting diodes (DUV LEDs) have been gaining attention. In this work, we propose a selective thermal oxidation (STO) process to fabricate ultra-small DUV micro-LEDs. Annealed in the air at 900°C for 2 h, the p-layers without SiO protection are oxidized into insulating oxides, and oxygen penetrates into parts of the quantum wells. In contrast, the patterned SiO protects the LED structure in the pixel regions. Therefore, micro-LED pixels are formed by the patterned SiO and thermal oxidation process rather than the conventional reactive ion etching. The formed oxide in the unprotected region can function as the insulation layer between p-n electrodes. Meanwhile, the boundary between the pixel and the surrounding oxide is naturally formed during thermal oxidation, which is a "self-aligned" process. Dielectric deposition, precise lithography alignment, and aperture etching in the conventional process are no longer required in STO-based micro-LED fabrication, which reduces production complexity and cost. Based on the STO process, we have achieved 2.3-µm DUV micro-LED standalone pixels and arrays with a 270-nm emission wavelength. The standalone DUV micro-LED is possibly the smallest reported in the literature to date, which has a low-operation voltage of 4.9 and 6.75 V at 10 and 1000 A/cm. Meanwhile, the fabricated DUV micro-LED arrays show leakage current density 4 × 10 A/cm at -5 V and a peak EQE of 0.77% under unpackaged conditions. We hope this work provides a new insight into micro-LED fabrication and further promotes future performance growth of DUV LEDs.
We report a simple, vacuum-compatible fiber attach process for in situ study of grating-coupled photonic devices. The robustness of this technique is demonstrated on grating-coupled waveguides exposed to multiple X-ra...
详细信息
ISBN:
(纸本)9798350369311
We report a simple, vacuum-compatible fiber attach process for in situ study of grating-coupled photonic devices. The robustness of this technique is demonstrated on grating-coupled waveguides exposed to multiple X-ray irradiations for aerospace studies.
Due to the intermittent characteristics of solar radiation, the integration of large-scale photovoltaic (PV) systems into the power grid raises many power quality problems such as voltage drop, unstable grid frequency...
Due to the intermittent characteristics of solar radiation, the integration of large-scale photovoltaic (PV) systems into the power grid raises many power quality problems such as voltage drop, unstable grid frequency, and harmonics. Despite these drawbacks, the integration of large-scale PV systems into the grid definitely has several advantages. This paper investigates the positive impact of integrating large-scale PV systems into the electric power grid. In this study, the PV system contributes 10%-20% of the power to the grid. Load flow analysis based on the Newton Raphson model is used to calculate grid losses when the PV system is connected at different positions along the feeder line. The results showed that there was a decrease in power losses that occurred in the network from 29.4 kW to 29.2 kW when the PV system was injected into the network at the start of the power line. Then losses can be reduced from 29.4 kW to 29.1 kW when the PV system is integrated in the midfield. The reduction in power losses becomes more significant when the PV system is injected at the end of the line from 29.4 to 28.6 kW. In conclusion, integration of the PV system into the power grid can improve the power loss and voltage profile.
This study is related to a system that enables elderly people to communicate interactively with young people who use existing message exchange services by simply speaking to an avatar on a tablet PC, without having to...
详细信息
As a novel 2D material, MoS 2 has shown excellent electrical properties and resistive switching characteristics to work as a switching layer for non-volatile memory. In this work, we drop cast the MoS 2 solution to ...
As a novel 2D material, MoS 2 has shown excellent electrical properties and resistive switching characteristics to work as a switching layer for non-volatile memory. In this work, we drop cast the MoS 2 solution to prepare the thin film and deposit an interfacial layer of Al 2 O 3 . We demonstrate the proposed memristive device with Cu/Al 2 O 3 /MoS 2 /Pt structure to work as an artificial synapse. The device shows a steady resistive switching behavior with the SET and RESET voltages of 1.3 V and -0.5 V, respectively. We further demonstrate the synapse behavior via a Hopfield Neural Network (HNN) and achieve image recognition and reconstruction with a high accuracy of 96% after 15 training epochs.
A discontinuous Galerkin time-domain scheme is formulated and implemented to analyze three-dimensional transient lasing dynamics. The proposed scheme solves a coupled system of the Maxwell and the rate equations. The ...
A discontinuous Galerkin time-domain scheme is formulated and implemented to analyze three-dimensional transient lasing dynamics. The proposed scheme solves a coupled system of the Maxwell and the rate equations. The atomic transitions through different energy levels are quantum-mechanically described by a four-level two-electron model, while the electro-magnetic interactions are treated using the Maxwell equations. The resulting solver accounts for the Pauli Exclusion Principle and permits robust simulation of lasing dynamics under optical pumping. Numerical results are presented to demonstrate the applicability and the accuracy of the proposed scheme.
暂无评论