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...Anything My Friend Shares, I Would Want to Support Them by Clicking on It : Co-Designing Story-Based Interventions Against Clickbait for Teenagers
No full textTeenagers\u27 lack of digital sophistication and cyber hygiene makes them vulnerable to social engineering attacks, especially as they start using social media. Clickbait, one of such attacks, is primarily performed through social media to trick users into clicking on malicious links. With teenagers\u27 increasing use of social media, clickbait poses a substantial threat to their online safety. The existing online safety measures for teens mainly focus on parental mediation, which can be perceived as restrictive and privacy-invasive. To this end, researchers recommended empowering teens to deal with online risks. In order to design such interventions for clickbait, we conducted co-design sessions with 27 teenagers aimed at understanding their perceptions of clickbait and co-designing countermeasures against it. Our findings suggest that teenagers are vulnerable to clickbait due to relevance and peer influence, where co-design activities reveal variations of interventions presenting their unique perspectives through storytelling. Overall, our study provides valuable insights into understanding teenagers\u27 needs and expectations around clickbait and interventions designed against it. We offer guidelines for future research in these directions based on our findings
Discrete Time Series Forecasting in Non-Invasive Monitoring of Managed Honey Bee Colonies: Part II: Are Hive Weight and In-Hive Temperature Seasonal and Colony-Specific
Get PDFWe explored the stationarity, trend, and seasonality of the hive weight and in-hive temperature of ten managed honey bee (Apis mellifera) colonies at a research apiary of the Carl Hayden Bee Research Center in Tucson, Arizona, USA. The hives were monitored with electronic scales and in-hive temperature sensors from June to October 2022. The weight and temperature were recorded every five minutes around the clock. The collected data were curated into 2160 timestamped weight and 2160 timestamped temperature observations. We performed a systematic autoregressive integrated moving average (ARIMA) time series analysis to answer three fundamental questions: (a) Does seasonality matter in the ARIMA forecasting of hive weight and in-hive temperature? (b) To what extent do the best forecasters of one hive generalize to other hives? and (c) Which time series type (i.e., hive weight or in-hive temperature) is better predictable? Our principal findings were as follows: (1) The hive weight and in-hive temperature series were not white noise, were not normally distributed, and, for most hives, were not difference- or trend-stationary; (2) Seasonality matters, in that seasonal ARIMA (SARIMA) forecasters outperformed their ARIMA counterparts on the curated dataset; (3) The best hive weight and in-hive temperature forecasters of the ten monitored colonies appeared to be colony-specific; (4) The accuracy of the hive weight forecasts was consistently higher than that of the in-hive temperature forecasts; (5) The weight and temperature forecasts exhibited common qualitative patterns
Privacy Rights: Their Evolution, Expansion, And Narrowing
No full textPrivacy rights in the United States have evolved significantly through judicial interpretation, with reproductive rights playing a central role in their expansion and contraction. This paper examines how the Supreme Court\u27s treatment of reproductive rights has shaped the broader understanding of constitutional privacy rights, focusing on landmark cases from Griswold v. Connecticut (1965) to Dobbs v. Jackson Women\u27s Health Organization (2022). The analysis begins by exploring how the Court first established privacy rights through penumbras found within various constitutional amendments, particularly in Griswold\u27s protection of contraceptive access for married couples. The paper traces the expansion of these rights through subsequent cases such as Eisenstadt v. Baird (1972), which extended contraceptive rights to unmarried individuals, and Roe v. Wade (1973), which established abortion as a constitutional right. These cases demonstrate how reproductive rights served as a vehicle for broadening privacy protections and expanding judicial review. The paper then examines how Planned Parenthood v. Casey (1992) modified Roe\u27s framework while preserving its essential holding, replacing the trimester system with an undue burden test that gave states greater latitude to regulate abortion while maintaining constitutional protections. This evolution shows how reproductive rights cases helped develop more sophisticated frameworks for balancing individual rights against state interests. The analysis culminates with an examination of Dobbs v. Jackson (2022), which overturned Roe and fundamentally reshaped the landscape of reproductive rights and privacy protections in the United States. The paper argues that this reversal highlights the instability of relying solely on judicial interpretation to protect fundamental rights and demonstrates the need for congressional action to establish stable, democratic protections for reproductive freedom. Throughout the discussion, the paper examines how the Court\u27s treatment of reproductive rights has influenced its approach to other privacy and autonomy rights. It argues that while judicial review has been crucial in protecting individual liberties, Congress should take the lead in establishing federal protections for reproductive rights. This would provide more stable and democratically legitimate safeguards while helping restore proper institutional roles in the constitutional system. The paper concludes that abortion rights are fundamental to human rights and civil liberties, deeply rooted in principles of personal autonomy, bodily integrity, and gender equality. It contends that protecting reproductive rights through federal legislation rather than judicial interpretation would better serve democratic values while ensuring consistent protection of these essential freedoms across the United States
Lightsheet Anomaly Resolution and Debris Observation (LARADO)
No full textSpace objects in the size range of 0.1 mm to 3 cm are not currently trackable but have enough kinetic energy for lethal consequences to spacecraft. Small orbital debris poses a risk to most space missions; the detection of this debris requires a combination of a large sensor area and large time coverage. For example, a sensor with a time area product of 3 m2years can make a significant contribution to our understanding of the near-Earth small debris population. Deploying large sensors like physical witness plates is resource intensive, due to their size and weight. The light sheet sensor concept allows the creation of a “virtual witness plate”, which needs no supporting physical structure and therefore presents a novel method for the detection of small debris anywhere from low Earth orbit to interplanetary space. Recent technology maturation efforts in the laboratory successfully demonstrated detection of small debris (1.6 mm diameter) moving at 6.38 km/s in support of the NRL-built, NASA-funded LARADO instrument, which itself is a technology maturation effort for a flight demonstration of the sensor on STPSat-7. In this paper, we will describe the instrument, present the laboratory data and analysis, and describe the autodetection algorithms for the DoD Space Test Program STPSat-7 launch in February of 2026
Analytical Method to Design and Develop 2-Stage Passive Vibration Isolator for Spacecrafts and Its On-Board Payloads
Get PDFSpacecrafts experience significant vibrations primarily during launch and sometimes in orbit, posing challenges to structural integrity and instrument performance. The methods to mitigate these vibrations, (or vibrations) in general primarily fall into two categories: disturbance absorption and source or receiver isolation. Among these two, isolation is preferred as fundamentally this is an additional system that either separates the source of the disturbance or the receiver effected in comparison to absorbers that reduce the magnitude of disturbance. Furthermore, its ability to provide greater control across varying frequency ranges relevant to spacecraft systems, provides the option of developing isolation systems with high efficiency. Isolation systems are further divided into passive and active approaches. Passive systems, which rely on mechanical components, are favored for their simplicity, reliability, and cost efficiency. Active systems, while offering finer control, are more complex, consume more power, and are relatively less reliable.
This research presents an analytical framework for designing passive isolation systems that address both transmitting and receiving elements. By systematically evaluating parameters such as mass, damping, and spring stiffness, the framework enables more targeted and efficient isolation system designs that align with spacecraft constraints. The study also compares the behavior of single-stage and two-stage isolators, offering insights into overcoming performance limitations associated with the former. By replacing traditional manual design methods with a structured analytical approach, this research simplifies the design process and broadens the practical integration of vibration isolation in small spacecraft
Novel Pressure-Based Electric Propulsion Discovery
Get PDFThis paper presents a novel electric propulsion system that uses pulsed plasma and ion- electron recombination to generate thrust primarily from internal pressure, using water vapor as propellant. In-space testing of the Poseidon™ thruster demonstrated 37.49 mN average thrust and over 4,800 seconds specific impulse at under 1.5 W input power. A physics-based model captures the full mass, energy, and momentum balances and matches experimental results, supporting pressure as the dominant thrust mechanism. Experimental detection of proton–boron fusion in the exhaust plume further validates the system\u27s plasma behavior and confirms a key element of its operating cycle
Qualification Testing and Initial Flights of the Payload Release Module – PRM™ 4-Point Dispensing Mechanism
Get PDFPoster presented during the 2025 SmallSat Conference
Development of a Compact Optical Communications Terminal for the PULSE-A CubeSat
No full textThe Polarization-modUlated Laser Satellite Experiment (PULSE-A) at the University of Chicago aims to demonstrate the feasibility of circular polarization shift keyed (CPolSK) satellite-to-ground laser communication links. The project aims to advance high-speed optical satellite-to-ground communications as an alternative to the traditionally used radio frequencies. PULSE-A thus requires the development of a compact, low-loss optical communications terminal capable of emitting collimated and high-power circularly polarized light modulated at high frequencies. Here we present a design for an optical communications terminal capable of achieving output powers of up to 230 mW at modulation frequencies from 1 to 10 MHz with a maximum coupled pointing error of less than 1 mrad. The optical communications terminal consists of two primary interrelated paths: (1) a collection path to gather, filter, and detect a 1064 nm beacon laser from the optical ground station and (2) a transmission path to emit, modulate, and amplify an outgoing 1550 nm transmission beam. During a pass, body-pointing aims the satellite’s optical aperture towards the ground station. The collection path gathers and focuses beacon light via a Keplerian beam condenser, blocks irrelevant wavelengths with a filter stack, and focuses the remaining light onto a quadrant photodiode detector. This detector supplies feedback to a fine steering mirror, which performs slight adjustments to center the beacon on the detector. The transmission path begins with two linear, orthogonally polarized seed lasers which encode data by alternately turning ON and OFF at a frequency of 1–10 MHz. This signal is then amplified to 250 mW using a random polarization erbium-doped fiber amplifier (EDFA) and passed through a quarter wave plate to convert the signal to circular polarization states. The collection and transmission paths are combined via an 1180 nm-cutoff shortpass dichroic mirror into a single optical path as they approach the fine steering mirror (FSM). This FSM- and detector-based feedback loop, pioneered by MIT’s CLICK-A and DLR’s OSIRIS4CubeSat missions for the CubeSat form factor, allows for a simple fine-pointing scheme where when the received beacon is aimed at the center of the quadrant photodiode in the collection path, the transmission beam and the ground station beacon are co-boresight. A 638 nm beacon subassembly with a significantly wider divergence assists the optical ground station with tracking the satellite’s location throughout transmission. Structurally, the use of fiber-optic connections and a baffling system will mitigate stray light and reduce the overall volume of the communications terminal. Current development includes optical component selection, simulation in Zemax OpticStudio, and testing of fiber-optic systems and the quadrant photodiode on the bench. The optical terminal design, along with its driving requirements, simulations and testing, and our approaches to various hurdles in creating a small form factor CPolSK optical communications terminal are presented here
Development and Qualification of an E Ink Thermal Control System for Tactically Responsive Satellites
No full textThe United States Space Force (USSF)\u27s objective to establish Tactically Responsive Space (TacRS) capabilities — the ability to integrate and launch a satellite within 24 hours — is hindered by the inflexible and time-consuming nature of conventional Thermal Control Systems (TCS). Current industry-standard design approach is a mission-specific process that relies on static materials with fixed thermo-optical properties, such as paints, silver teflon tapes, and multi-layer insulation blankets.
This traditional approach creates a significant bottleneck, as the development of the TCS cannot begin until a customer\u27s payload and orbit details are confirmed. This introduces an incompressible 3-6 month lead time for hardware procurement, fabrication, and integration into the critical path of the satellite build. The resulting thermal system is permanently configured for a single mission profile, making it impractical to adapt to evolving requirements or different orbits without a complete and costly redesign. This legacy methodology is fundamentally incompatible with the need for rapid, versatile, and reconfigurable satellite buses required for TacRS missions
ChantSat-1 Ground Station Planning, Design and Installation - Experiences Gained
No full textPlanning, designing, and implementing the ground station for ChantSat-1, Coastal Carolina University’s first small sat mission program, was the first major milestone of the University’s space program. CCU’s ChantSat-1 ground station team presents the experiences gained during the process from inception to completion of the ground station at a liberal arts public University in the southeastern United States with approximately 11,000 students. By sharing both our challenges and successes, our goal is to support others by providing experiences gained in the process