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Compact Laser Communication Terminal Architecture And In-Orbit Demonstration, P. Johan Du Plooy, Steven Engelen, Jacob J. Hejderup, Tushar Goyal Aug 2023

Compact Laser Communication Terminal Architecture And In-Orbit Demonstration, P. Johan Du Plooy, Steven Engelen, Jacob J. Hejderup, Tushar Goyal

Small Satellite Conference

Satellites are generating more data than ever due to more demanding payloads, although communications Down To Earth (DTE) have not experienced the same growth in data rates. Compact Laser Communication Terminals are a promising technology that will increase bandwidths (10 Gbit+) and pave the way for larger data volumes to be transmitted which will increase the relevance of small and CubeSats in space data as service offerings. The in-orbit demonstrator is targeting a downlink data rate of 1 Gbit/s with a range of up to 1000km. A downlink wavelength of 1545nm is used while 1590nm is used for the ground …


Mechanical Aeration And Liquid Dairy Manure: Application Impacts On Grassland Runoff Water Quality And Yield, T. J. Basden, S. B. Shah, J. L. Miller Aug 2023

Mechanical Aeration And Liquid Dairy Manure: Application Impacts On Grassland Runoff Water Quality And Yield, T. J. Basden, S. B. Shah, J. L. Miller

IGC Proceedings (1977-2023)

Wet weather on heavy soils reduces oxygen availability in the root zone and reduces forage yields. Mechanical aeration can improve forage yield in these soil conditions. Research has shown that under certain conditions, mechanical aeration can increase yield by improving drainage and aeration (Davies et al., 1989); aeration can also increase depression, storage and infiltration thus reducing surface runoff and improving nutrient distribution in the root zone. Aeration on sloping, fertilised grassland can provide environmental (Douglas et al., 1995) and agronomic benefits. The objectives of this study were to evaluate the runoff water quality and agronomic impacts of …


Qualification Of Inter-Satellite Link Laser Communication Terminals On Cubesats - Cubeisl, Benjamin Rödiger, Jorge Rosano Nonay, Christian Roubal, René Rüddenklau, Christopher Schmidt, Jan Paul Jakobs Aug 2023

Qualification Of Inter-Satellite Link Laser Communication Terminals On Cubesats - Cubeisl, Benjamin Rödiger, Jorge Rosano Nonay, Christian Roubal, René Rüddenklau, Christopher Schmidt, Jan Paul Jakobs

Small Satellite Conference

Free Space Optical (FSO) communications on the rise to replace classic Radio-Frequency (RF) systems in many sectors of satellite communication. DLR has a long heritage in developing Laser Communication Terminals (LCT’s) for LEO satellites. Major requirement for the design of the terminals is the optical characterization. Beside the verification in the laboratory, the terminals must withstand the harsh conditions of launch and space and fulfil all functionalities.

To characterize the LCT’s optical properties, DLR developed and built an Optical Ground Support Equipment (OGSE) which mirrors the functionalities of an Optical Ground Station (OGS), in a small scale, to test and …


Commercial Data Relay Services In The Cis-Lunar Environment With Sstl’S Lunar Pathfinder, Ramy Kozman, Alex Da Silva Curiel Aug 2023

Commercial Data Relay Services In The Cis-Lunar Environment With Sstl’S Lunar Pathfinder, Ramy Kozman, Alex Da Silva Curiel

Small Satellite Conference

Many missions are planned for the lunar environment in the coming decades. Traditionally, all missions would receive telecommands direct-from-Earth and send payload data and telemetry direct-to-Earth. However, missions can benefit from reduced size, weight, power and costs and increased data rates if they forgo space-borne direct-to/from-Earth communications hardware and instead communicate with a nearby cis-lunar data relay orbiter.

Accordingly, SSTL has been working with the European Space Agency under the auspices of the Commercial Lunar Missions Support Services partnership agreement to provide Lunar communications and navigations services. This agreement will see SSTL design, build, test and operate the Lunar Pathfinder …


Design And Build Process Of A Small Satellite Deployable Uhf Antenna, Alejandro Castro, David Sadowski, Dmitriy Obukhov, Ryan Hiser, Nazia Mozaffar, Brendan Hill Aug 2023

Design And Build Process Of A Small Satellite Deployable Uhf Antenna, Alejandro Castro, David Sadowski, Dmitriy Obukhov, Ryan Hiser, Nazia Mozaffar, Brendan Hill

Small Satellite Conference

This article presents a design, development, and testing process of a deployable right-hand circular polarization (RHCP) helical antenna for a small satellite in the UHF band. In the stowed configuration the antenna is 5cm and deploys to an operational length of 74cm. Deployment of the antenna is controlled by a DC motor and once released, extends to its full shape under spring power, a 3-turn jack-in-the-box design. The antenna is tuned and matched to correct frequency bandwidth and features an optical deployment confirmation circuit. The antenna produces an axial mode, with an average beamwidth of 60° and this is achieved …


Complete Issue - Vol. 82, No. 3 And 4 Aug 2023

Complete Issue - Vol. 82, No. 3 And 4

Journal of Mississippi History

No abstract provided.


Recent Manuscript Accessions To Repositories At Mississippi Universities And The Mississippi Department Of Archives And History, Mona Vance-Ali Aug 2023

Recent Manuscript Accessions To Repositories At Mississippi Universities And The Mississippi Department Of Archives And History, Mona Vance-Ali

Journal of Mississippi History

No abstract provided.


Beeson Academy/Hattiesburg Prep: A History In Context, Stuart J. Levin Aug 2023

Beeson Academy/Hattiesburg Prep: A History In Context, Stuart J. Levin

Journal of Mississippi History

No abstract provided.


Photographic Documentation Of Brierfield: "The House Jeff Built", Gary Mcquarrie, Brooks C. Place Aug 2023

Photographic Documentation Of Brierfield: "The House Jeff Built", Gary Mcquarrie, Brooks C. Place

Journal of Mississippi History

No abstract provided.


A Digital Risk Twin For The Design And Certification Of A Distributed Space Based Space Surveillance System, Samuel Hilton Aug 2023

A Digital Risk Twin For The Design And Certification Of A Distributed Space Based Space Surveillance System, Samuel Hilton

Small Satellite Conference

Objectives

  • Development of a Digital Risk Twin (DRT) of a Distributed Satellite System Mission to perform Preliminary Mission Reliability Estimates
  • Quantify mission reliability considering platform reliability and required System of System s (SoS) configuration for mission assurance
  • Provide ability to perform rapid trade studies on Mission Reliability given varied SmallSat platform and distributed configuration requirements


Towards Comprehensive Ai-Based Onboard Fdir: System Design And First Results, Luca Manca, Gianluca Campagna, Riccardo Maderna, Gabriele Giordana Aug 2023

Towards Comprehensive Ai-Based Onboard Fdir: System Design And First Results, Luca Manca, Gianluca Campagna, Riccardo Maderna, Gabriele Giordana

Small Satellite Conference

Health monitoring of spacecrafts is a crucial task in Space operations. Fault Detection, Isolation and Recovery (FDIR) plays a critical role in ensuring the safety and successful operation of a spacecraft by detecting and isolating faults, and then executing recovery actions. Currently, the FDIR process is carried out mostly on ground, with only anomaly detection typically performed onboard the spacecraft using out-of-limit (OOL) threshold techniques, whereas fault isolation and recovery is managed by operators on the ground.

This approach has two major limitations. Firstly, OOL approach is not capable of identifying subtle anomalies that occur within the parameters’ nominal operational …


Toward Autonomous Guidance And Control: A Robust Ai-Based Solution For Low-Thrust Orbit Transfers, Matteo Stoisa, Luca Romanelli, Federica Paganelli Azza, Pietro De Marchi, Mattia Varile Aug 2023

Toward Autonomous Guidance And Control: A Robust Ai-Based Solution For Low-Thrust Orbit Transfers, Matteo Stoisa, Luca Romanelli, Federica Paganelli Azza, Pietro De Marchi, Mattia Varile

Small Satellite Conference

The focus of our initial application scenario centers around a low-thrust orbit transfer in Low-Earth Orbit (LEO). This specific use-case has been chosen due to its inherent challenges, including the requirements for robustness and real-time computation.

We propose an AI-based solution capable of autonomous and robust on-board G&C. The core of our approach leverages a Deep Neural Network (DNN) trained through Reinforcement Learning (RL) techniques. Our method aims at enhancing a traditional guidance approach by managing environmental perturbations, it processes the on-board navigation coordinates and provides the thrust to be imposed by the propulsion subsystem.

Our approach demonstrates effectiveness in …


Development Of Monopropellant 98% Htp Thrusters For Small Satellite Propulsion Modules: Technical Challenges And Solutions, Pawel Surmacz, Adrian Parzybut, Zbigniew Gut, Mariusz Rosiak, Michal Alaszkiewicz Aug 2023

Development Of Monopropellant 98% Htp Thrusters For Small Satellite Propulsion Modules: Technical Challenges And Solutions, Pawel Surmacz, Adrian Parzybut, Zbigniew Gut, Mariusz Rosiak, Michal Alaszkiewicz

Small Satellite Conference

No abstract provided.


Signal-Agnostic Technique For Satellite Doppler Correction, Salwan Damman, Nazia Mozaffar, Brendan Hill Aug 2023

Signal-Agnostic Technique For Satellite Doppler Correction, Salwan Damman, Nazia Mozaffar, Brendan Hill

Small Satellite Conference

Low Earth Orbit satellites impart a Doppler shift on transmitted signals. This Doppler shift imposes challenges on the receiver design. Optimum band-edge filters can measure the Doppler offset, and frequency-locked loops (FLLs) containing them can correct the Doppler offset. However, optimum band-edge filters require knowledge of the structure of the signal of interest in order to compute the filter coefficients. Prefilter delay-multiply elements can be used to generate a Doppler tone that can be placed in an FLL, but this technique also requires knowledge of the signal structure and is not well suited for frequency shift keyed signals. It is …


Breaking The Smallsat Barriers To Sub-50cm Imaging, Hamilton Law, Alex Da Silva Curiel, Andrew Haslehurst, Steven Knox, Victoria Irwin, Martin Sweeting Aug 2023

Breaking The Smallsat Barriers To Sub-50cm Imaging, Hamilton Law, Alex Da Silva Curiel, Andrew Haslehurst, Steven Knox, Victoria Irwin, Martin Sweeting

Small Satellite Conference

New cutting-edge imaging sensors can now reduce instrument size and mass, leading to mission cost savings, and bring sub-50cm imaging capability into the realm of small satellites. Whilst aperture is essential to achieving resolution, half-pixel shifted sensor architectures decouple achievable Ground Sampling Distance (GSD) from the native ground projected pixel. This facilitates the deployment of Very High Resolution (VHR) small satellite constellations featuring improved Signal-to-Noise performance and increased area collection rates compared to push-frame systems.

A fundamental limitation to the theoretical performance of an optical system is imposed by its aperture diameter; hence, for a given aperture, the aim is …


Confronting Or Linking Csp And Ccsds? A View On How To Operate Small Satellites Today, Pierre-Alexis Lagadrillière, Tobias Brügge, Kay Müller Aug 2023

Confronting Or Linking Csp And Ccsds? A View On How To Operate Small Satellites Today, Pierre-Alexis Lagadrillière, Tobias Brügge, Kay Müller

Small Satellite Conference

CubeL was launched early 2021 and is the first COTS cubesat which the German Space Operations Center (GSOC) of DLR is operating. It carries 3 of the most typical space-to-ground communication systems with its UHF transceiver, its S-band transceiver and its laser terminal. Main aim is to demonstrate the capabilities of the miniaturized laser terminal for high speed communications up to 100Mbps. The second aim of this cubesat is to test operations between the on-board S-band transceiver with its native CSP and GSOC’s multi-mission environment based on CCSDS and ECSS protocols and standards, e.g. the CCSDS space packet protocols.

In …


Moon Orbiter "Izumi" For Lunar Water Exploration, Kentaro Taniguchi, Miwa Tsurumi, Ryusei Komatsu Aug 2023

Moon Orbiter "Izumi" For Lunar Water Exploration, Kentaro Taniguchi, Miwa Tsurumi, Ryusei Komatsu

Small Satellite Conference

NASA's Artemis program focuses on the water resources on the Moon. As lunar exploration probes with high spatial resolutions can identify potential drilling points on the lunar surface, this study proposes a mission that focuses on neutrons generated by galatic cosmic rays that leak into space and contain information regarding the amount of water within the lunar subsurface. Neutron detectors used in previous lunar exploration mission probes have encountered challenges in achieving both high spatial resolution and statistical reliability. To overcome these challenges, the proposed mission satellite is equipped with the world's first imager proposed for thermal neutrons. The satellite …


Lost: An Open-Source Suite Of Star Tracking Software, Mark Polyakov, Edward Zhang, Karen Haining Aug 2023

Lost: An Open-Source Suite Of Star Tracking Software, Mark Polyakov, Edward Zhang, Karen Haining

Small Satellite Conference

We present LOST: Open-source Star Tracker (LOST), a suite of star tracking software particularly suitable for small satellite missions with limited computing resources and low-cost cameras. LOST contains implementations of a number of previously-proposed star tracking algorithms and a flexible framework for running and evaluating these algorithms. Our evaluation finds that LOST's algorithms are simultaneously able to maintain a strong combination of accuracy, runtime, and memory usage. In scenarios representative of a low-cost star tracker, LOST correctly identifies over 95% of images, and importantly, performs the entire star tracking pipeline in less than 35 milliseconds on a Raspberry Pi while …


Responding To Disproportionate Skin Cancer Rates Affecting Adult Men Aged 18-60, Aaron Thompson Aug 2023

Responding To Disproportionate Skin Cancer Rates Affecting Adult Men Aged 18-60, Aaron Thompson

Capstone Collection

Skin cancer is a deadly disease that kills significantly more men than women every year. At the same time, women are more than twice as likely to apply daily sun protection factor (SPF) than men. This research study explores how key stakeholders within the skin care industry have responded to the data showing increasing disparities between male and female skin cancer rates. To fulfill the objectives of this research study, qualitative data was collected from six semi-structured interviews with adult males between the ages of 18 and 60. The interviews were intentionally designed to engage with the American, adult male’s …


Static Malware Family Clustering Via Structural And Functional Characteristics, David George, Andre Mauldin, Josh Mitchell, Sufiyan Mohammed, Robert Slater Aug 2023

Static Malware Family Clustering Via Structural And Functional Characteristics, David George, Andre Mauldin, Josh Mitchell, Sufiyan Mohammed, Robert Slater

SMU Data Science Review

Static and dynamic analyses are the two primary approaches to analyzing malicious applications. The primary distinction between the two is that the application is analyzed without execution in static analysis, whereas the dynamic approach executes the malware and records the behavior exhibited during execution. Although each approach has advantages and disadvantages, dynamic analysis has been more widely accepted and utilized by the research community whereas static analysis has not seen the same attention. This study aims to apply advancements in static analysis techniques to demonstrate the identification of fine-grained functionality, and show, through clustering, how malicious applications may be grouped …


Using Geographic Information To Explore Player-Specific Movement And Its Effects On Play Success In The Nfl, Hayley Horn, Eric Laigaie, Alexander Lopez, Shravan Reddy Aug 2023

Using Geographic Information To Explore Player-Specific Movement And Its Effects On Play Success In The Nfl, Hayley Horn, Eric Laigaie, Alexander Lopez, Shravan Reddy

SMU Data Science Review

American Football is a billion-dollar industry in the United States. The analytical aspect of the sport is an ever-growing domain, with open-source competitions like the NFL Big Data Bowl accelerating this growth. With the amount of player movement during each play, tracking data can prove valuable in many areas of football analytics. While concussion detection, catch recognition, and completion percentage prediction are all existing use cases for this data, player-specific movement attributes, such as speed and agility, may be helpful in predicting play success. This research calculates player-specific speed and agility attributes from tracking data and supplements them with descriptive …


Traditional Vs Machine Learning Approaches: A Comparison Of Time Series Modeling Methods, Miguel E. Bonilla Jr., Jason Mcdonald, Tamas Toth, Bivin Sadler Aug 2023

Traditional Vs Machine Learning Approaches: A Comparison Of Time Series Modeling Methods, Miguel E. Bonilla Jr., Jason Mcdonald, Tamas Toth, Bivin Sadler

SMU Data Science Review

In recent years, various new Machine Learning and Deep Learning algorithms have been introduced, claiming to offer better performance than traditional statistical approaches when forecasting time series. Studies seeking evidence to support the usage of ML/DL over statistical approaches have been limited to comparing the forecasting performance of univariate, linear time series data. This research compares the performance of traditional statistical-based and ML/DL methods for forecasting multivariate and nonlinear time series.


A Hybrid Ensemble Of Learning Models, Bivin Sadler, Dhruba Dey, Duy Nguyen, Tavin Weeda Aug 2023

A Hybrid Ensemble Of Learning Models, Bivin Sadler, Dhruba Dey, Duy Nguyen, Tavin Weeda

SMU Data Science Review

Statistical models in time series forecasting have long been challenged to be superseded by the advent of deep learning models. This research proposes a new hybrid ensemble of forecasting models that combines the strengths of several strong candidates from these two model types. The proposed ensemble aims to improve the accuracy of forecasts and reduce computational complexity by leveraging the strengths of each candidate model.


Development Of Tactical And Strategic Operations Software For Nasa's Lunar Flashlight Mission, Mason Starr Aug 2023

Development Of Tactical And Strategic Operations Software For Nasa's Lunar Flashlight Mission, Mason Starr

Small Satellite Conference

Lunar Flashlight (LF) is an interplanetary CubeSat mission designed to demonstrate the use of a novel green monopropellant propulsion system and characterize lunar surface ice with a near-infrared laser array and reflectometer. LF is also the first Jet Propulsion Laboratory (JPL) mission to be operated entirely by students. While JPL provided baseline tools to Georgia Tech (GT), bespoke tools and software were developed by GT operators. Four tools developed by the author are discussed in this paper: (1) Downlink Helper is a Graphical User Interface (GUI) tool which improves the tactical downlink of recorded spacecraft telemetry. The tool automatically creates …


Cost-Effective Payload Operations Planning Software For Complex Small Spacecraft Mission Operations, Willard Farmer Aug 2023

Cost-Effective Payload Operations Planning Software For Complex Small Spacecraft Mission Operations, Willard Farmer

Small Satellite Conference

As small spacecraft become more capable, so does the complexity of their operations. Searching for potential concurrent observation or access opportunities and ensuring they are compatible with one another may become tedious and repetitive for operators to manually compute. Currently available commercial-off-the-shelf tools that automate this process are capable but expensive. To address this problem, a new payload operations planning tool has been developed by the Space Flight Laboratory to handle the deterministic aspects of mission planning, such as: detecting observation opportunities, validating observations in a schedule, and generating lists of commands to be sent to satellites. This lightweight tool …


Evaluating Rotation-Equivariant Deep Learning Models For On-Orbit Cloud Segmentation, Alex Meredith Aug 2023

Evaluating Rotation-Equivariant Deep Learning Models For On-Orbit Cloud Segmentation, Alex Meredith

Small Satellite Conference

Cloud detection in satellite imagery is key for autonomously taking and downlinking cloud-free images of a target region as well as studying cloud-climate interactions and calibrating microwave radiometers. We propose a C8-equivariant dense U-Net, a rotation-equivariant deep learning model, trained on visible-spectrum, long-wave infrared (LWIR), and short-wave infrared (SWIR) imagery for on-orbit cloud detection. We train this model on the SPARCS1 dataset of Landsat 8 images and compare it to three related deep learning models, two rule-based algorithms, and to the literature. Additionally, we compare a C8-equivariant dense U-Net trained on VIS, LWIR, and SWIR …


T Cell Receptor Engineering Targeting Foxm1 For The Treatment Of Lung Cancer, Isabel M. Perez-Sandi, Alexandre Reuben, Minying Zhang, Hui Nie, Peixin Jiang, Cassian Yee, Gregory Lizee, John V. Heymach Aug 2023

T Cell Receptor Engineering Targeting Foxm1 For The Treatment Of Lung Cancer, Isabel M. Perez-Sandi, Alexandre Reuben, Minying Zhang, Hui Nie, Peixin Jiang, Cassian Yee, Gregory Lizee, John V. Heymach

Summer Experience 2023

No abstract provided.


Data On Deck: A Case Study Of A Historic Undersea Film And Video Digitization Project, Karen Urbec Mlis, Ca, Audrey Mickle Mlis, Lisa Raymond Aug 2023

Data On Deck: A Case Study Of A Historic Undersea Film And Video Digitization Project, Karen Urbec Mlis, Ca, Audrey Mickle Mlis, Lisa Raymond

Journal of Contemporary Archival Studies

In 2021, the Woods Hole Oceanographic Institution (WHOI) Data Library and Archives (DLA), a part of the MBLWHOI (Marine Biological Laboratory Woods Hole Oceanographic Institution) Library, received a grant from the Council on Library and Information Resources (CLIR) Recordings at Risk (RAR) program to catalog, digitize, preserve, and make available historic films and videos of Alvin, the first-of-its-kind manned submersible vessel that has shown us more of the deep ocean than had ever been possible and transformed our understanding of life on Earth.

These moving images have not been accessible to researchers and were far past the intended life cycle …


Functional Connectivity Varies Across Scales In A Fragmented Landscape, Kate I. T. Bird, Daniel R. Uden, Craig R. Allen Aug 2023

Functional Connectivity Varies Across Scales In A Fragmented Landscape, Kate I. T. Bird, Daniel R. Uden, Craig R. Allen

School of Natural Resources: Faculty Publications

Species of different sizes interact with the landscape differently because ecological structure varies with scale, as do species movement capabilities and habitat requirements. As such, landscape connectivity is dependent upon the scale at which an animal interacts with its environment. Analyses of landscape connectivity must incorporate ecologically relevant scales to address scale-specific differences. Many evaluations of landscape connectivity utilize incrementally increasing buffer distances or other arbitrary spatial delineations as scales of analysis. Instead, we used a mammalian body mass discontinuity analysis to objectively identify scales in the Central Platte River Valley (CPRV) of Nebraska, U.S.A. We implemented a graph-theoretic network …


Convergence: Eos News And Updates, August 2023, Unh Institute For The Study Of Earth, Oceans And Space Aug 2023

Convergence: Eos News And Updates, August 2023, Unh Institute For The Study Of Earth, Oceans And Space

Convergence: EOS News and Updates

No abstract provided.