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Articles 61 - 90 of 522
Full-Text Articles in Aerospace Engineering
Program And Proceedings: Nebraska Academy Of Sciences 1880–2025, 145th Anniversary Year, One Hundred-Thirty-Fifth Annual Meeting
Nebraska Academy of Sciences: Programs and Proceedings
Program
Aeronautics and Space Science
Biological and Medical Sciences
Biology
Chemistry
Earth Sciences
Science Education
Anthropology
Applied Science and Technology
Physics and Engineering
Forensic Sciences
Ecology, Sustainability, and Environmental Science
Maiben Lecture: Mary Ann Vinton, "State of the Academy"
Friends of Science Awards: David Crouse and Daniel Sitzman
Factors Contributing To Fatalities In Helicopter Emergency Medical Service Accidents, Jenna Korentsides, Joseph R. Keebler, Mihhail Berezovski, Alex Chaparro
Factors Contributing To Fatalities In Helicopter Emergency Medical Service Accidents, Jenna Korentsides, Joseph R. Keebler, Mihhail Berezovski, Alex Chaparro
Publications
INTRODUCTION: T his study aimed to update and reinforce previous research on helicopter emergency medical service accidents in the United States. By investigating predictors of fatalities after helicopter emergency medical service crashes through the application of machine learning techniques, we updated existing data sets and sought to uncover patterns that traditional analysis might not reveal.
METHODS: Using the National Transportation Safety Board database, the authors analyzed a dataset of 267 helicopter emergency medical service accidents between 1991–2022. We first calculated fatalities odds ratios for each condition. We then plotted geospatial locations of all reported accidents. Finally, we used XGBoost regression …
Integrating Satellite-Based Precipitation Analysis: A Case Study In Norfolk, Virginia, Imiya M. Chathuranika, Dalya Ismael
Integrating Satellite-Based Precipitation Analysis: A Case Study In Norfolk, Virginia, Imiya M. Chathuranika, Dalya Ismael
Engineering Technology Faculty Publications
In many developing cities, the scarcity of adequate observed precipitation stations, due to constraints such as limited space, urban growth, and maintenance challenges, compromises data reliability. This study explores the use of satellite-based precipitation products (SbPPs) as a solution to supplement missing data over the long term, thereby enabling more accurate environmental analysis and decision-making. Specifically, the effectiveness of SbPPs in Norfolk, Virginia, is assessed by comparing them with observed precipitation data from Norfolk International Airport (NIA) using common bias adjustment methods. The study applies three different methods to correct biases caused by sensor limitations and calibration discrepancies and then …
Security Enhancement In Uav Swarms: A Case Study Using Federated Learning And Shap Analysis, Sushmitha Halli Sudhakara, Lida Haghnegahdar
Security Enhancement In Uav Swarms: A Case Study Using Federated Learning And Shap Analysis, Sushmitha Halli Sudhakara, Lida Haghnegahdar
School of Cybersecurity Faculty Publications
As cyber-physical systems (CPSs) increasingly integrate physical and digital realms, securing critical infrastructure, such as the Port of Virginia, becomes paramount. Among CPSs, Unmanned Aerial Vehicles (UAVs) are vital for monitoring, communication, and supporting the command and control through remote reconnaissance and surveillance missions. These UAV applications often require coordination, planning, and runtime reconfiguration, traditionally managed by human decision-makers. However, this approach has limitations, as extensively documented in the literature. Artificial Intelligence (AI) has emerged as a pivotal tool to address these limitations, enhancing risk mitigation and informed decision-making. This research proposes a machine learning (ML) based security mechanism, leveraging …
Sex-Dependent Changes In Risk-Taking Predisposition Of Rats Following Space Radiation Exposure, Elliot Smits, Faith E. Reid, Ella N. Tamgue, Paola Alvarado Arriaga, Charles Nguyen, Richard A. Britten
Sex-Dependent Changes In Risk-Taking Predisposition Of Rats Following Space Radiation Exposure, Elliot Smits, Faith E. Reid, Ella N. Tamgue, Paola Alvarado Arriaga, Charles Nguyen, Richard A. Britten
Department Radiation Oncology & Biophysics Faculty Publications
The Artemis missions will establish a sustainable human presence on the Moon, serving as a crucial steppingstone for future Mars exploration. Astronauts on these ambitious missions will have to successfully complete complex tasks, which will frequently involve rapid and effective decision making under unfamiliar or high-pressure conditions. Exposure to low doses of space radiation (SR) can impair key executive functions critical to decision making. This study examined the effects of exposure to 10 cGy of Galactic Cosmic Ray simulated radiation (GCRsim) on decision-making performance in male and female rats with a naturally low predisposition for risk-taking (RTP) prior to exposure. …
A Two-Hit Model Of Executive Dysfunction: Simulated Galactic Cosmic Radiation Primes Latent Deficits Revealed By Sleep Fragmentation, Richard A. Britten, Ella N. Tamgue, Paola Arriaga Alvarado, Arriyam S. Fesshaye, Larry D. Sanford
A Two-Hit Model Of Executive Dysfunction: Simulated Galactic Cosmic Radiation Primes Latent Deficits Revealed By Sleep Fragmentation, Richard A. Britten, Ella N. Tamgue, Paola Arriaga Alvarado, Arriyam S. Fesshaye, Larry D. Sanford
Department Radiation Oncology & Biophysics Faculty Publications
Future Artemis-class missions to Mars will expose astronauts to prolonged space radiation (SR), sleep disruption, and operational demands requiring greater autonomy, placing decision making and executive function at heightened risk. Both SR and sleep fragmentation (SF) independently impair cognition, yet their combined effects remain poorly understood. Using the Associative Recognition Memory and Interference (ARMIT) task, we assessed cognitive performance in male rats exposed to 10 cGy of Galactic Cosmic Ray simulation (GCRsim), SF, or both. Under well-rested conditions, GCRsim-exposed rats exhibited overt deficits in the C.1.2 stage, performing at chance when reinforcement contingencies shifted, consistent with impaired cognitive flexibility. In …
The Interacting Roles Of Attention Allocation And Trust In Highly Automated Aam Environments, Yusuke Yamani
The Interacting Roles Of Attention Allocation And Trust In Highly Automated Aam Environments, Yusuke Yamani
Psychology Faculty Publications
[First slide]
Mechanisms of attentive visual processing
- Attention control
- Visual search
- Eye movement
- Aging and individual differences
Limits of human performance in applied environment
- Complex displays
- Machine operation
- Surface transportation
- Advanced air mobility
- Nuclear operation
Methods to ameliorate human cognitive performance
- Human-machine interface
- Human autonomy/AI teaming
- Human-systems integration
- Training
Ai, American Politics, And Modern Warfare, Madisen Campbell
Ai, American Politics, And Modern Warfare, Madisen Campbell
Space and Defense
As artificial intelligence (AI) transforms modern warfare, it will pose profound ethical challenges for America’s constitutional democracy.
Technological advancements in the world today, particularly the field of artificial intelligence (AI), impact the current political system in the United States. The importance of understanding and addressing the complex challenges and opportunities of incorporating AI into American politics is key to developing a profound understanding of AI in modern warfare and the implications it has for policy making in America. The need for policy makers and military leaders to receive insight on the development of AI and to develop strategic approaches for …
U.S. 5g Technology Policy: Competition Or Boycott?, Wes Ferguson, Kyle Vargus
U.S. 5g Technology Policy: Competition Or Boycott?, Wes Ferguson, Kyle Vargus
Space and Defense
Rather than corral allies and partners across the globe into boycotting Chinese 5G telecommunication systems, U.S. officials should embrace free-and-fair trade competition against China, even in products and services where China may enjoy a technological lead.
The race for technological supremacy has emerged as a defining characteristic of the newest era of great power competition. China and the United States compete to become the dominant world power. Each side is racing to create the latest and most elite technologies to catapult themselves into the lead and give them the edge over their adversary. The fifth generation of wireless technology, called …
Atomic Assurance: Funding A Modern U.S. Test Readiness Program, Mark Tang
Atomic Assurance: Funding A Modern U.S. Test Readiness Program, Mark Tang
Space and Defense
To address intensified strategic competition with Russia and China, the United States should reinstate funding for a modern nuclear Test Readiness Program.
The U.S. has never faced the threat of two adversarial powers with nuclear arsenals that equal our own. With the emphasis on great power competition and mounting aggression by both China and Russia, the risk of conflict with either or both powers is growing. Currently, the U.S. is ill prepared for the possible existential challenge that is deterring conflict with two major nuclear peer adversaries. America’s defense strategy and approach towards the international order must change to protect …
Earth To Orbit: Three Models For Strengthening Space Deterrence, Anton Dahm
Earth To Orbit: Three Models For Strengthening Space Deterrence, Anton Dahm
Space and Defense
Nuclear, cyber, and integrated deterrence models hold lessons for space deterrence strategy, including declared thresholds, resilient space architecture, and the embrace of international competition in technological innovation.
The United States depends heavily on space capabilities, significantly more than any other country. Not only does space enable navigation, communications, environmental monitoring, and other vital capabilities, but space has also been described as the most essential warfighting domain. However, the U.S. space architecture mirrors its early days: relying on important, expensive payloads on a limited number of satellites. While providing important capabilities to U.S. decision-makers, kinetic and non-kinetic weapons can easily target …
The German Zeitenwende: Turning Point Or Blind Alley?, Savannah Hollen
The German Zeitenwende: Turning Point Or Blind Alley?, Savannah Hollen
Space and Defense
The Zeitenwende, or turning point, announced by Chancellor Olaf Scholz after Russia’s invasion of Ukraine in February 2022, may end up leaving Germany with few good defense policy options.
After Russia’s invasion of Ukraine in 2022, Germany vowed to change course, to expand and modernize its military, which for decades has been weak relative to the size of Europe’s leading economy. As bold as Germany’s declarations have been, German leaders may well have walked into a blind alley, unsure of exactly how Zeitenwende will happen, what the final results will be, or the consequences if they never come close to …
Strategic Space Cooperation: U.S. Space Command And The National Guard’S State Partnership Program, David Moore, Jesse Morehouse, Patrick Mitchell
Strategic Space Cooperation: U.S. Space Command And The National Guard’S State Partnership Program, David Moore, Jesse Morehouse, Patrick Mitchell
Space and Defense
In 2022, the U.S. Space Command (USSPACECOM) and the National Guard's State Partnership Program (SPP) began pursuing security cooperation objectives while integrating the space domain into greater deterrence efforts. As the newest combatant command (CCMD) with space as its Area of Responsibility (AOR), USSPACECOM has global strategic partnership interests and recognizes the value of the enduring relationships inherent in SPP. This cooperation allows the National Guard to offer its strong relationships, space expertise, and industry knowledge to USSPACECOM. This provides a foundation for USSPACECOM's security cooperation efforts. This article discusses the SPP's role in supporting USSPACECOM's engagement strategy and the …
Arms Control Optimism And Great Power Competition, Damon Coletta
Arms Control Optimism And Great Power Competition, Damon Coletta
Space and Defense
In its unjust war, Russia rakes at Ukrainian civilian targets using dual-capable missiles. China meanwhile tightens the screws on Taiwan as it cements its friendship with Russia and continues its buildup of strategic nuclear warheads.1 Conventional wisdom and U.S. policy under such tense conditions unduly discount expectations for arms control.2 Arms control, in the popular mind, centers on bans in testing or deployment, and is therefore terminally associated with disarmament. Trepidation about disarmament fuels assumptions in polarized democracy, and the United States in particular, about the narrow political conditions under which arms control can succeed during great power competition. Conventional …
Drone-Based, Boost-Phase Intercept Of North Korean Icbms, James D. Wells, William Priedhorsky, Frederick Lamb, Laura Grego
Drone-Based, Boost-Phase Intercept Of North Korean Icbms, James D. Wells, William Priedhorsky, Frederick Lamb, Laura Grego
Space and Defense
North Korea currently has an adversarial relationship with the United States and has successfully tested both nuclear weapons and intercontinental-range ballistic missiles (ICBMs) capable of striking the continental United States.1 There are several ways the United States could attempt to address the threat posed by North Korea’s nuclear-armed ICBMs. Historically, the United States has relied on a policy of projecting military strength, fostering strong alliances, and maintaining a credible threat of retaliation to deter adversaries, including those with nuclear weapons, from initiating hostilities. Some have argued that this approach has been instrumental in preventing conflict between nuclear-armed nations, including North …
A Premature Obituary For Conventional Deterrence, Jeffery S. Lehmkuhl
A Premature Obituary For Conventional Deterrence, Jeffery S. Lehmkuhl
Space and Defense
As the United States (US) continues to shift its weight of effort towards great power competition, some scholars and practitioners have questioned the relevance of conventional forces and their ability to deter. Chief among them is Sean McFate, who asserts that “conventional war is unicorn hunting” and that “no one fights that way anymore.”1 Jim Sciutto echoes McFate’s claims in his book The Shadow War and states that the US is losing to Russia and China in a new way of warfare that is conducted below the threshold of conventional warfare.2 Leading Russian General Valery Gerasimov furthered this claim when …
Nuclear Regimes In The 21st Century, Stephen J. Cimbala, Adam Lowther
Nuclear Regimes In The 21st Century, Stephen J. Cimbala, Adam Lowther
Space and Defense
The modern nuclear operations practitioner is facing a more complex future than at any point since the height of the Cold War. Understanding the past, present, and possible future of nuclear force structure and doctrine offers the policy maker a useful way to make sense of unfolding events and place them within a broader context. With China, Russia, and North Korea all posing a growing nuclear risk to the United States, a strong grasp on the available options for countering these threats is certainly important.
Editor's Note, Damon Coletta
Table Of Contents Vol. 15 No. 2
Space And Defense Vol. 15 No. 2 Fall 2024 (Whole Issue)
Space And Defense Vol. 15 No. 2 Fall 2024 (Whole Issue)
Space and Defense
No abstract provided.
Impact Of Weather Systems On Uav Parameters Using Computational Fluid Dynamics, Saif Aljuhaishi, Yaseen K. Al-Timimi, Basim I. Wahab
Impact Of Weather Systems On Uav Parameters Using Computational Fluid Dynamics, Saif Aljuhaishi, Yaseen K. Al-Timimi, Basim I. Wahab
Karbala International Journal of Modern Science
Since drones cannot fly in any kind of weather, they are not safe for time-sensitive activities. The study examines how the passage of weather systems in Iraq leads to the ban on drone flights, and how these weather conditions impact the aerodynamic forces of the drone. Hourly climate data for the study area were obtained from ECMWF ERA5 and CAMS in NetCDF format for four climate stations (Erbil, Baghdad, Rutbah, and Basrah). A ScanEagle drone was chosen for this study. The Python programming language was used to perform mathematical operations to calculate the ban on drone flights. ArcGIS 10.8 was …
Notes For Contributors To Space & Defense
Front Matter, Damon Coletta
Reflections On Improving Industrial Investment And Financing Environment To Promote Healthy Development Of Commercial Aerospace, Cuilin Wu, Chao Zhang, Quan Cheng, Hongyu Wu
Reflections On Improving Industrial Investment And Financing Environment To Promote Healthy Development Of Commercial Aerospace, Cuilin Wu, Chao Zhang, Quan Cheng, Hongyu Wu
Bulletin of Chinese Academy of Sciences (Chinese Version)
As a new frontier in global technological competition, the sustainable development of the commercial aerospace industry highly depends on a sound and efficient investment and financing environment. Although China’s commercial aerospace investment and financing system has achieved initial progress, it still faces multiple challenges, including imbalanced capital structure, insufficient risk-sharing mechanisms, and weakened market incentives, which constrain industrial innovation and competitiveness. This study systematically analyzes the current status and main challenges of China’s commercial aerospace investment and financing environment and draws on international experience to propose following optimization strategies. First, improve the structure of capital supply and expand diversified financing …
Benefits And Challenges Of Constructing Low-Altitude Air Route Network Infrastructure For Developing Low-Altitude Economy, Xiaohan Liao, Chenchen Xu, Huping Ye
Benefits And Challenges Of Constructing Low-Altitude Air Route Network Infrastructure For Developing Low-Altitude Economy, Xiaohan Liao, Chenchen Xu, Huping Ye
Bulletin of Chinese Academy of Sciences (Chinese Version)
Low-altitude airspace is a resource that needs to be fully explored, and the low-altitude economy is a new type of economic activity resulted from low-altitude airspace exploration and utilization. As the primary players of low-altitude flight activities, the commercialization and wide applications of unmanned aerial vehicles (UAVs) are promoting the prosperity of the low-altitude economy. A low-altitude air route network is an effective means to ensure the safe and efficient operations of a large number of UAVs, and it is also a new key infrastructure hosting low-altitude traffic. The history shows that the investment on public transport infrastructure as a …
Beyond Innovation Paradox: Practices And Reflections On Promoting High-Quality Development Of Commercial Aerospace With Low Costs, Chao Zhang, Qianshu Shi, Binbin Meng, Quan Cheng, Jun Zhao, Weitao Wu
Beyond Innovation Paradox: Practices And Reflections On Promoting High-Quality Development Of Commercial Aerospace With Low Costs, Chao Zhang, Qianshu Shi, Binbin Meng, Quan Cheng, Jun Zhao, Weitao Wu
Bulletin of Chinese Academy of Sciences (Chinese Version)
Commercial spaceflight, as a national strategic emerging industry, is critical for seizing the high ground of the space economy and fostering new quality productive forces through its low-cost and high-quality development. Currently, international enterprises represented by SpaceX have gained a leading advantage through technological breakthroughs and business model innovations, posing severe challenges to China’s aerospace security and development. This study first analyzes the evolutionary trajectory of low-cost development in commercial spaceflight, then delves into the “low-cost vs. high-quality” innovation paradox faced by the traditional aerospace industry and its root causes. Building on this analysis, it examines the experiences of international …
Suggestions On Expanding Application Scenarios Of Commercial Aerospace Market, Mengru Dong, Chaofeng Huang, Ningyi Yang, Yu Yao, Yafeng Qin
Suggestions On Expanding Application Scenarios Of Commercial Aerospace Market, Mengru Dong, Chaofeng Huang, Ningyi Yang, Yu Yao, Yafeng Qin
Bulletin of Chinese Academy of Sciences (Chinese Version)
Expanding the application scenarios of the commercial aerospace market is an inevitable requirement for promoting the transformation and upgrading of the space industry and achieving the strategic goal of becoming a leading space power. Currently, the development of China’s commercial aerospace is in a critical transition period from technological breakthroughs to market expansion. However, there are still problems such as insufficient participation of private enterprises, low penetration of consumer markets, and insufficient competitiveness in the international market, and a sustainable and benign commercial closed loop has not yet been formed. The study analyzes the current situation of commercial aerospace market …
Disciplinary Policy Research On Science Development Strategies For Crewed Lunar Exploration, Wei Yang, Yuyang He, Jinting Kang, Ruiyi Chen, Huihong Cheng, Li Sun, Pan Deng, Yong Wei, Yangting Lin, Xianhua Li
Disciplinary Policy Research On Science Development Strategies For Crewed Lunar Exploration, Wei Yang, Yuyang He, Jinting Kang, Ruiyi Chen, Huihong Cheng, Li Sun, Pan Deng, Yong Wei, Yangting Lin, Xianhua Li
Bulletin of Chinese Academy of Sciences (Chinese Version)
In order to better serve China’s crewed lunar exploration, this study researched and analyzed the current status of lunar exploration and planetary science research in China and the United States. Additionally, we conducted interviews and a questionnaire survey with experts in planetary science and deep-space exploration, and formed the following four policy recommendations: 1) Strengthening the layout and management of the disciplines of lunar and planetary sciences, and setting up a long-term and stable funding mechanism; 2) Improving the system of talent cultivation, and encouraging young talents to participate in deep-space exploration missions; 3) Strengthening the protection of original ideas, …
Situation And Challenges In Development Of China’S Commercial Aerospace, Chaofeng Huang, Chao Zhang, Jinge Li, Mengru Dong
Situation And Challenges In Development Of China’S Commercial Aerospace, Chaofeng Huang, Chao Zhang, Jinge Li, Mengru Dong
Bulletin of Chinese Academy of Sciences (Chinese Version)
Commercial aerospace is an important support for the national aerospace power strategy and a “new growth engine” for economic development, serving as a strategic pivot to win the future competitive landscape. Currently, China’s commercial aerospace industry is facing a mixed and urgent situation. On the one hand, the international competition situation is severe, with frequency track resources being seized and squeezed, international rules being passively constrained, and global market breakthroughs being hindered. On the other hand, domestic development opportunities are highlighted. The multidimensional support of central local cooperation is constantly strengthening, and the development prospects driven by industrial demand are …
Analysis Of Status, Challenges, And Optimization Recommendations For China’S Commercial Space Policy Support System, Liming Ge, Zixuan Liu, Mingda Yang, Wenbin Ma
Analysis Of Status, Challenges, And Optimization Recommendations For China’S Commercial Space Policy Support System, Liming Ge, Zixuan Liu, Mingda Yang, Wenbin Ma
Bulletin of Chinese Academy of Sciences (Chinese Version)
As a strategic pillar in building a space power, commercial space has become a new frontier for global technological competition. The Chinese government and relevant regulatory authorities have introduced a series of multi-level policy documents, propelling the commercial space sector into a phase of vigorous development. This study systematically reviews the background, evolution, and implementation outcomes of China’s policy support system for commercial space. It is indicates that, in light of the goal of becoming a “space power” and the future industrial competition, China’s policy support system for commercial space still faces challenges such as ineffective policy implementation mechanisms, lack …