Search

In June of 1994, the term "planetary defense" was first published in a white paper included in a U.S. Air Force report called SPACECAST 2020. The white paper warned of the threat of potentially hazardous asteroids to Earth and suggested methods of asteroid impact mitigation through an organized Air Force program. Today, the United States strongly contributes to the world-wide effort to find, track, characterize, and mitigate potentially hazardous objects (PHOs) via the NASA Planetary Defense Coordination Office (PDCO). This paper analyzes the evolution of U.S. planetary defense since SPACECAST 2020 and evaluates the influence of the white paper's recommendations nearly thirty years on. [ABSTRACT FROM AUTHOR]

In the event of a conflict or contingency on the Korean Peninsula, one of the five People’s Liberation Army (PLA) theater commands is responsible for implementing China’s military strategy and operations in Korea—the Northern Theater Command (NTC). What capabilities does China deploy to the NTC? How does it compare to the other theater commands? And do NTC’s military capabilities change the existing balance of power on the Korean Peninsula? Using the most up-to-date data, this paper offers, first, a theater-level comparative analysis of the PLA and, second, a quantitative assessment of how China’s NTC capabilities affect the military balance of power between North Korea on the one hand, and South Korea and the U.S. Forces Korea on the other. Of PLA’s five theater commands, the paper finds that the NTC has maintained the largest and heaviest ground force, the largest air force, and the second most powerful naval fleet. When NTC military capabilities are added to the existing military balance between North Korean forces and the U.S.– South Korean alliance forces, the United States and South Korea’s air supremacy is challenged and naval dominance is overturned. This is especially the case in the West Sea of Korea, the Yellow Sea. [ABSTRACT FROM AUTHOR]

Reasonable distribution of braking force is a factor for a smooth, safe, and comfortable braking of trains. A dynamic optimal allocation strategy of electric-air braking force is proposed in this paper to solve the problem of the lack of consideration of adhesion difference of train wheelsets in the existing high-speed train electric-air braking force optimal allocation strategies. In this method, the braking strategy gives priority to the use of electric braking force. The force model of a single train in the braking process is analyzed to calculate the change of adhesion between the wheel and rail of each wheelset after axle load transfer, and then the adhesion of the train is estimated in real time. Next, with the goal of maximizing the total adhesion utilization ratio of trailer/ motor vehicles, a linear programming distribution function is constructed. The proportional coefficient of adhesion utilization ratio of each train and the application upper limit of braking force in the function is updated according to the change time point of wheelset adhesion. Finally, the braking force is dynamically allocated. The simulation results of Matlab/Simulink show that the proposed algorithm not only uses the different adhesion limits of each trailer to reduce the total amount of braking force undertaken by the motor vehicle, but also considers the adhesion difference of each wheelset. The strategy can effectively reduce the risk and time of motor vehicles during the braking process and improve the stability of the train braking. [ABSTRACT FROM AUTHOR]

This paper is concerned with the well-posedness and asymptotic behavior of solutions for the following extensible beam equation with non-local energy damping u tt + Δ 2 u - κ ϕ (‖ ∇ u ‖ 2 ) Δ u - φ (‖ Δ u ‖ 2 + ‖ u t ‖ 2) Δ u t + f (u) = h. More specifically, this is a complementary work to the paper by Sun and Yang (Discrete Contin Dyn Syst Ser B 27(6):3101–3129, 2022), where the authors consider this model assuming the hypothesis that φ ∈ C 1 (R +) with non-degenerate condition φ (s) > 0 , s ∈ R + . They prove the existence of strong global and exponential attractors and their robustness on the perturbed extensibility parameter κ . In this paper assuming φ (s) ⪆ γ s q which contemplates the degenerate condition φ (0) = 0 , we prove the existence of weak and regular solutions to the problem proposed and employing the method given in Temam (Springer-Verlag, New York, 1998) we show that the dynamic system (X , S t) given by the weak solutions of the problem has a compact global attractor in the weak topology of the phase space X. This class of nonlinear beams arising in connection with models for flight structures with non-local energy damping is proposed by Balakrishnan and Taylor (Proceedings Damping 89, Flight Dynamics Lab and Air Force Wright Aeronautical Labs, WPAFB, 1989). [ABSTRACT FROM AUTHOR]

This article proposes possible solutions for the Royal Canadian Air Force (RCAF) to implement best practices, particularly in terms of the skills to be identified and developed for project managers. It has been clearly established that project performance and success are closely linked to the skills of project managers. The more skills are adapted to the characteristics and complexities of major RCAF projects, the greater the chances of success. [ABSTRACT FROM AUTHOR]

This paper presents a proximal bundle (PB) framework based on a generic bundle update scheme for solving the hybrid convex composite optimization (HCCO) problem and establishes a common iteration-complexity bound for any variant belonging to it. As a consequence, iteration-complexity bounds for three PB variants based on different bundle update schemes are obtained in the HCCO context for the first time and in a unified manner. Although two of the PB variants are universal (i.e., their implementations do not require parameters associated with the HCCO instance), the other newly (as far as the authors are aware) proposed one is not, but has the advantage that it generates simple—namely, one-cut—bundle models. The paper also presents a universal adaptive PB variant (which is not necessarily an instance of the framework) based on one-cut models and shows that its iteration-complexity is the same as the two aforementioned universal PB variants. Funding: Financial support from the Office of Naval Research [N00014-18-1-2077] and the Air Force Office of Scientific Research [Grant FA9550-22-1-0088] is gratefully acknowledged. [ABSTRACT FROM AUTHOR]

Sample average approximation (SAA), the standard approach to stochastic mixed-integer programming, does not provide guidance for cases with limited computational budgets. In such settings, variance reduction is critical in identifying good decisions. This paper explores two closely related ensemble methods to determine effective decisions with a probabilistic guarantee. (a) The first approach recommends a decision by coordinating aggregation in the space of decisions as well as aggregation of objective values. This combination of aggregation methods generalizes the bagging method and the "compromise decision" of stochastic linear programming. Combining these concepts, we propose a stopping rule that provides an upper bound on the probability of early termination. (b) The second approach applies efficient computational budget allocation for objective function evaluation and contributes to identifying the best solution with a predicted lower bound on the probability of correct selection. It also reduces the variance of the upper bound estimate at optimality. Furthermore, it adaptively selects the evaluation sample size. Both approaches provide approximately optimal solutions even in cases with a huge number of scenarios, especially when scenarios are generated by using oracles/simulators. Finally, we demonstrate the effectiveness of these methods via extensive computational results for "megascale" (extremely large scale) stochastic facility location problems. History: Accepted by Pascal Van Hentenryck, Area Editor for Computational Modeling: Methods & Analysis. Funding: This work was supported by The Office of Naval Research [Grant N00014-20-1-2077] and the Air Force Office of Scientific Research [Grant FA9550-20-1-0006]. Supplemental Material: The software that supports the findings of this study is available within the paper and its Supplemental Information (https://pubsonline.informs.org/doi/suppl/10.1287/ijoc.2021.0324) as well as from the IJOC GitHub software repository (https://github.com/INFORMSJoC/2021.0324). The complete IJOC Software and Data Repository is available at https://informsjoc.github.io/. [ABSTRACT FROM AUTHOR]

A University Affiliated Research Center (UARC) is a highly valued engineering, research, and development resource to the federal government, largely within the US Department of Defense (DoD). Only 15 exist, all under special authority of the US Code. The Systems Engineering Research Center (SERC), established in 2008, was the first UARC established as a networked research center, gradually growing to include more than two dozen university members, each offering systems engineering research capabilities. This networked model for a UARC has found support within the DoD—exemplified by the newest UARC established recently by the US Air Force. A large diverse pool of faculty and student researchers arguably delivers the most consequential academic research in systems engineering anywhere in the world. In its first few years, the SERC had to overcome challenges that single‐university UARCs did not face in exchange for the advantages that such a sizable network of universities offers. This review paper explores those challenges, offering lessons for new network‐based UARCs and other network‐based university research centers. Systems engineering communities, globally, are exploring such constructs, and this reflective paper may offer useful insights. [ABSTRACT FROM AUTHOR]

This paper investigates a model-free algorithm of broad interest in reinforcement learning, namely, Q-learning. Whereas substantial progress had been made toward understanding the sample efficiency of Q-learning in recent years, it remained largely unclear whether Q-learning is sample-optimal and how to sharpen the sample complexity analysis of Q-learning. In this paper, we settle these questions: (1) When there is only a single action, we show that Q-learning (or, equivalently, TD learning) is provably minimax optimal. (2) When there are at least two actions, our theory unveils the strict suboptimality of Q-learning and rigorizes the negative impact of overestimation in Q-learning. Our theory accommodates both the synchronous case (i.e., the case in which independent samples are drawn) and the asynchronous case (i.e., the case in which one only has access to a single Markovian trajectory). Q-learning, which seeks to learn the optimal Q-function of a Markov decision process (MDP) in a model-free fashion, lies at the heart of reinforcement learning. When it comes to the synchronous setting (such that independent samples for all state–action pairs are drawn from a generative model in each iteration), substantial progress has been made toward understanding the sample efficiency of Q-learning. Consider a γ-discounted infinite-horizon MDP with state space S and action space A : to yield an entry-wise ε-approximation of the optimal Q-function, state-of-the-art theory for Q-learning requires a sample size exceeding the order of | S ‖ A | (1 − γ) 5 ε 2 , which fails to match existing minimax lower bounds. This gives rise to natural questions: What is the sharp sample complexity of Q-learning? Is Q-learning provably suboptimal? This paper addresses these questions for the synchronous setting: (1) when the action space contains a single action (so that Q-learning reduces to TD learning), we prove that the sample complexity of TD learning is minimax optimal and scales as | S | (1 − γ) 3 ε 2 (up to log factor); (2) when the action space contains at least two actions, we settle the sample complexity of Q-learning to be on the order of | S ‖ A | (1 − γ) 4 ε 2 (up to log factor). Our theory unveils the strict suboptimality of Q-learning when the action space contains at least two actions and rigorizes the negative impact of overestimation in Q-learning. Finally, we extend our analysis to accommodate asynchronous Q-learning (i.e., the case with Markovian samples), sharpening the horizon dependency of its sample complexity to be 1 (1 − γ) 4 . Funding: Y. Chen is supported in part by the Alfred P. Sloan Research Fellowship, the Google Research Scholar Award, the Air Force Office of Scientific Research [Grant FA9550-22-1-0198], the Office of Naval Research (ONR) [Grant N00014-22-1-2354], and the National Science Foundation (NSF) [Grants CCF-2221009, CCF-1907661, DMS-2014279, IIS-2218713, and IIS-2218773]. Y. Wei is supported in part by the Google Research Scholar Award and the NSF [Grants CCF-2106778, DMS-2147546/2015447, and CAREER award DMS-2143215]. Y. Chi is supported in part by the ONR [Grants N00014-18-1-2142 and N00014-19-1-2404] and the NSF [Grants CCF-1806154, CCF-2007911, CCF-2106778, ECCS-2126634, and DMS-2134080]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/opre.2023.2450. [ABSTRACT FROM AUTHOR]

Program coverage customization selectively adds instrumentation to a compiled computer program so that a limited amount of directly observed data can be used to infer other program coverage information after a run. A good instrumentation plan can reduce run-time overheads while still giving software developers the information they need. Unfortunately, optimal coverage planning is NP-hard, limiting either the quality of heuristic plans or the sizes of programs that can be instrumented optimally. We exploit the monotonicity property of feasible instrumentations to formulate this problem as an intraprocedural set covering problem. Our formulation has an exponential number of constraints, and we design a polynomial-time separation algorithm to incrementally add the necessary subset of these inequalities. Our approach reduces expected run-time probing costs compared with existing methods, offers a guarantee of the optimality of the instrumentation, and has compilation-time overhead suitable for wide practical use. History: Accepted by Pascal Van Hentenryck, Area Editor for Computational Modeling: Methods & Analysis. Funding: This work was supported by the National Science Foundation [Grants CCF-1318489, CCF-1420866, and CCF-1423237] and the Air Force Research Laboratory [Grant FA8750-14-2-0270]. Supplemental Material: The software that supports the findings of this study is available within the paper and its Supplemental Information (https://pubsonline.informs.org/doi/suppl/10.1287/ijoc.2021.0349) as well as from the IJOC GitHub software repository (https://github.com/INFORMSJoC/2021.0349). The complete IJOC Software and Data Repository is available at https://informsjoc.github.io/. [ABSTRACT FROM AUTHOR]

In this paper, we study adjustable robust optimization (ARO) problems with discrete uncertainty. Under a very general modeling framework, we show that such two-stage robust problems can be exactly reformulated as ARO problems with objective uncertainty only. This reformulation is valid with and without the fixed recourse assumption and is not limited to continuous wait-and-see decision variables unlike most of the existing literature. Additionally, we extend an enumerative algorithm akin to a branch-and-cut scheme for which we study the asymptotic convergence. We discuss how to apply the reformulation on two variants of well-known optimization problems, a facility location problem in which uncertainty may affect the capacity values and a multiple knapsack problem with uncertain weights, and we report extensive computational results demonstrating the effectiveness of the approach. History: Accepted by Andrea Lodi, Area Editor for Design & Analysis of Algorithms – Discrete. Funding: This work was supported by the Air Force Office of Scientific Research [Grants FA8655-20-1-7012, FA8655-20-1-7019]. [ABSTRACT FROM AUTHOR]

Cooperative adaptive cruise control (CACC) is one of the control methods that improves fuel efficiency by allowing multiple vehicles to drive in groups. In this paper, we propose a robust CACC with a heterogeneous vehicle using a disturbance observer. The longitudinal vehicle dynamics, including the engine dynamics, have been modeled as a first-order model using a time constant. However, the simplified first-order model varies in accuracy depending on the dynamic driving situation due to engine performance and air drag force. Designing a more accurate higher-order model might be a solution, but this has a high computational cost. Thus, we propose an augmented state observer for model uncertainties and disturbances. The proposed method makes it possible to design a CACC using nominal parameters without considering dynamic changes to the model parameters. Also, the proposed method can directly compensate for disturbances, compared to the adaptation technique, while also satisfying string stability. The proposed method was validated via computational simulations for heterogeneous traffic and experimental evaluation. [ABSTRACT FROM AUTHOR]

Taking into account the uncertainty of the enemy's air actions during the organization of assets protection from their strikes is a decisive factor in the successful task fulfillment by air defense forces. The impact of the enemy's air actions uncertainty is assessed by the task non-fulfillment risks by air defense forces to protect assets from enemy's strikes. The article describes the method of determining the task non-fulfillment risks by air defense forces based on the use of a fuzzy-multiple approach. The risk is advisable to be taken into account together with the results of evaluating the combat effectiveness of air defense forces when making decisions on the organization of assets protection from the enemy's air attack. [ABSTRACT FROM AUTHOR]

The interest in flying wings dates as far as the early years of the aviation age. Early investigations of the feasibility of the concept demonstrated increased aerodynamic efficiency and reduced fuel consumption. However, structural, engine integration, and stability and control issues prevented further development. In the 1990s, a new concept, the blended wing body (BWB), was created to alleviate some of the concerns of flying wings while maintaining increased efficiency and adding further benefits, such as reduced pollutant and noise emissions. Despite the promise, technical hurdles once again proved to be a deal breaker and, as of 2024, the only successful flying wing is the B-2 Spirit, an extremely complex and expensive aircraft. Nowadays, with the world quickly transitioning towards cleaner energy, the interest in the BWB has been renewed. The latest technological advancements in the aerospace industry should make its development more plausible; however, passenger comfort issues remain. Surprisingly, the BWB development may come from an unexpected application, as a tanker aircraft. As the U.S. Air Force is seeking a replacement to hundreds of aging tankers, a startup company was recently funded to develop the concept and build a prototype. In this study, we explore the history of blended designs from its early days, highlighting its opportunities and challenges—and why the design is an intriguing fit for application as a tanker aircraft. [ABSTRACT FROM AUTHOR]

We describe how we used contextual teaching and learning principles to build a graph theory project for mathematics courses at the U.S. Air Force Academy. We leveraged an Air Force targeting scenario to make the mathematics relevant to our students. We explain the details of the project, the mathematics behind it, and how we incorporated contextual teaching and learning to improve the learning experience of our students. Although our project focused on an Air Force application, due to the ubiquitous nature of graph matchings, the project could be easily modified for other audiences. [ABSTRACT FROM AUTHOR]

Military pilot education, including flight training, is a long, expensive, and complex process. The main goal is to produce as many skilled professionals as possible ready to perform flight tasks on the front-line aircraft and push them to their workload limits with complete control. To achieve this goal, it is necessary to select and educate young people with the aptitude and abilities to perform the most demanding military flight tasks. The creation of a model for the education and training of military pilots depends on the requirements of the Czech Air Force Command and the teaching capacities of the University of Defence and the Aviation Training Centre in Pardubice. Rearmament of the Czech Air Force and the required number of pilots requires a change in the new military pilot training model. This contribution describes a new approach to Czech Air Force pilot education and training in the current security conditions in the world. [ABSTRACT FROM AUTHOR]

The article is a review of the television series "Masters of the Air," specifically focusing on season 1, episode 3. The reviewer compares the series to the film "Twelve O' Clock High" and discusses the similarities and differences between the two. The review also provides background information on the Eighth Air Force and the challenges they faced during World War II. It highlights the tension between the crews and the leadership of the Eighth Air Force and discusses the planning and execution of a bombing mission. The review concludes by mentioning episode 4, which shifts the focus to the contributions of women and other support personnel in the war effort. [Extracted from the article]

Scholarship of analytic standards generally focuses on their application in strategic intelligence assessments. Yet analytic standards are underexplored in other environments, particularly tactical and operational military intelligence analyses. These environments challenge many assumptions that generally underpin the implementation of analytic standards, including multi-analyst quality control chains and a focus on rigor as the primary measure of quality. The US Air Force’s implementation of analytic standards offers an illustration of how such standards can be applied in military intelligence environments. To successfully employ analytic standards in tactical and operational intelligence environments, emphasis must be placed on accrediting analysts themselves as well as their output. The rigor-led model of analytic standards must also be broadened to give greater weight to other attributes of quality intelligence analysis. [ABSTRACT FROM AUTHOR]

Combat air forces tacticians and operational planners have yet to understand the B-21 Raider’s potential capability. Leadership’s vision is clear, but service-level parochial interests, insular platform cultures, and competition for resources are creating unhealthy tensions within the combat air forces, Department of the Air Force, and across the Joint force. Such tensions could severely hamper tactical creativity, operational planning, and strategic competition, ultimately undermining the US Air Force’s effectiveness against a peer adversary. Amid the move toward pulsed operations, a rift has emerged between standoff and stand-in tactical philosophies. Yet the B-21 Raider’s family of systems at a minimum operates in both areas, likely demanding a reconsideration of these concepts. Such a reconsideration can also help the Air Force transcend stealth/nonstealth and fighter/bomber debates to embrace new levels of tactical creativity. [ABSTRACT FROM AUTHOR]

Objective: Chronic kidney disease (CKD) is one of the most common diseases worldwide. The increasing prevalence and incidence of CKD have contributed to the critical problem of high medical costs. Due to stressful environments, aircrew members may have a high risk of renal dysfunction. A better strategy to prevent CKD progression in Air Force personnel would be to diagnosis CKD at an early stage. Since few studies have been conducted in Taiwan to examine the long-term trends in early CKD in Air Force aircrew members, this study is highly important. We investigated the prevalence of CKD and established a predictive model of disease variation among aircrew members. Materials and Methods: In this retrospective study, we included all subjects who had received physical examinations at a military hospital from 2004 to 2010 and who could be tracked for four years. The Abbreviated Modification of Diet in Renal Disease Formula (aMDRD) was used to estimate the glomerular filtration rate (GFR) and was combined with the National Kidney Foundation/ Kidney Disease Outcomes Quality Initiative (NKF-K/DOQI) to identify CKD patients. Results: A total of 212 aircrew members were assessed. The results showed that the prevalence of CKD was 3.8%, 9.4%, 9.0%, and 9.4% in each of the four years. According to the logistic regression analysis, abnormal urobilinogen levels, ketones, and white blood cell (WBC) counts in urine and a positive urine occult blood test increased the risk of CKD. A positive urine occult blood test can be used to predict the future risk of CKD. Moreover, the generalized estimating equation (GEE) model showed that a greater risk of CKD with increased examination time, age and seniority had a negative effect. In conclusion, abnormal urobilinogen levels, ketones, and urine WBC counts in urine as well as a positive urine occult blood test might serve as independent predictors for CKD. Conclusion: In the future, we can focus not only on annual physical examinations but also on simple and accurate examinations, such as urine occult blood testing, to determine the risk of CKD and prevent its progression in our aircrew members. [ABSTRACT FROM AUTHOR]

The purpose of this article is to analyse the process of equipping the Polish Air Force with the F-16 aircraft. The Polish F-16 programme serves as an essential source of knowledge for avoiding errors that may occur when introducing new weapon systems in Poland, or other post-communist countries that are still reliant on Soviet-designed military technologies. Due to various external and internal factors, not all elements of the F-16 programme are suitable for replication in the acquisition of new weapon systems; however, some solutions have been applied in Poland's F-35 and WISŁA air defence programmes. The authors examined selected aspects of the F-16 programme, including its historical background, legal and organisational framework, personnel training, infrastructure, logistics, and the economic implications of the offset agreement. [ABSTRACT FROM AUTHOR]

This article argues that while India is preparing for the contingency of a two-front war against China and Pakistan, its procurement and arms production policies make it problematic for the Indian Air Force (IAF) and Indian Navy (IN) to meet these challenges. IAF doctrine is not aligned to its current capabilities and is, therefore, largely speculative. Further, due to budgetary shortfalls in its modernization efforts, the IAF will find it difficult to fulfill its stated doctrinal role against China or Pakistan. On the other hand, the Indian Navy's doctrine is better aligned with its objectives and capabilities. The IN can carry out its doctrine of sea control against the Pakistani Navy, but will have to adopt a sea denial posture against China because of the rapid growth of the PLA Navy's force and capabilities. Given their slow pace of modernization, neither service will be able to decisively counter the Chinese military. [ABSTRACT FROM AUTHOR]

This article takes the reader on a journey from the foundation of the world's first independent air service to the contemporary operating environment, as space is recognised as a unique strategic domain. Using the Smuts Report, and a framework of culture, concepts and capabilities, Clifford Fletcher-Jones shows how the conditions that led to the requirement for an independent air force are present today–thus requiring an independent space service. The research grounds the argument for an independent space service in space power theory before articulating a set of recommendations to the British government to enable the UK to achieve its 'Galactic Britain' ambition.◼ [ABSTRACT FROM AUTHOR]

Star copolymer films were produced by using spin-coating, drop-casting, and casting deposition techniques, thus obtaining ultrathin and thick films, respectively. The morphology is generally flat, but it becomes substrate-dependent for ultrathin films where the planarization effect of films is not efficient. The indentation hardness of films was investigated by Force Volume Maps in both the air and liquid. In the air, ultrathin films are in the substrate-dominated zone and, thus, the elastic modulus E is overestimated, while E reaches its bulk value for drop-casted ultrathin and thick films. In liquid (water), E follows an exponential decay for all films with a minimum soaked time t0 of 0.37 and 2.65 h for ultrathin and drop-casted ultrathin and thick films, respectively. After this time, E saturates to a value on average 92% smaller than that measured in the air due to film swelling. Such results support the role of film morphology in the antimicrobial activity envisaged in the literature, suggesting also an additional role of film hardness. [ABSTRACT FROM AUTHOR]

Army installation commanders need timely weather information to make installation closure decisions before or during adverse weather events (e.g., hail, thunderstorms, snow, and floods). We worked with the military installation in Fort Carson, CO, and used their Weather Warning, Watch, and Advisory (WWA) criteria list to establish the foundation for our algorithm. We divided the Colorado Springs area into 2300 grids (2.5 square kilometers areas) and grouped the grids into ten microclimates, geographically and meteorologically unique regions, per pre-defined microclimate regions provided by the Fort Carson Air Force Staff Weather Officers (SWOs). Our algorithm classifies each weather event in the WWA list using the National Weather Service's and National Digital Forecast Database's data. Our algorithm assigns each event a criticality level: none, advisory, watch, or warning. The traffic network data highlight the importance of each road segment for travel to and from Fort Carson. The algorithm also uses traffic network data to assign weight to each grid, which enables the aggregation to the region and installation levels. We developed a weather dashboard in ArcGIS Pro to verify our algorithm and visualize the forecasted warnings for the grids and regions that are or may be affected by weather events. [ABSTRACT FROM AUTHOR]

A comparative study was conducted on Levitation Frame with Mid-set Air Spring (LFMAS) and Levitation Frame with End-set Air Spring (LFEAS). First of all, the work done by air spring force and by track excitation on two levitation frames were analysed, respectively, and the mechanism of the low dynamic interaction of LFMAS with guideway was explained theoretically; then, dynamics simulation and coupled vibration test on LFEAS and LFMAS were carried out using coupled vibration test bench of single levitation frame. Theoretical equations show that both the work done by the air spring forces and by track excitation on LFMAS are less than those on LFEAS under the same vibration condition, demonstrating that LFMAS has better levitation stability than LFEAS. Simulation and test results show that the fluctuation of levitation gap as well as the vibration acceleration of track beam platform, levitation frame and car-body of LFMAS are all smaller than those of LFEAS; with the increase of sine excitation frequency or vehicle speed, the superiority of LFMAS in dynamics performance is more obvious. [ABSTRACT FROM AUTHOR]

One of the largest public sector operations in the world is within the United States of America military, with over 2 million service members and approximately 1.4 million full-time equivalent civilian workers, with bases and operations in at least 80 different nations. The US military made COVID-19 vaccinations (COVAX) mandatory among all members but allows for requests to accommodate refusals for reasons of personal beliefs. These can be beliefs of conscience, personal morality or religious expression, whether from organized or individual tenets. Multiple articles have been produced during the COVID-19 pandemic identifying willingness to receive COVAX or reasons for COVAX reluctance and refusal, but almost all data has been obtained from short-response surveys. Taking a departure from that, this study reviews the qualitative data from over 100 extensive interviews conducted with individual military members (from the US Air Force) who requested COVAX exemption. Their reasons given to refuse vaccination are also provided in a letter written by the member, regardless of rank, directly to the general at the top of their particular command. Examination of the reasons given provides unique insights into the thought processes of requestors. Regardless of the request’s outcome, this data demonstrates the administrative and policy importance placed by the US military on at least considering personal beliefs, even in a pandemic, and protecting individual freedoms, even of military members with curtailed rights. By far, disproportionate requests came from lower ranks with some mid-level leadership making formal requests to refuse the COVAX. In this sample, no top leadership requested exemptions. The analysis finds evidence for pressure exerted on members to not submit an exemption request. For those who did, the 111 requests were not a static or set doctrinal view. Arising from at least 29 distinct religious traditions, all requests showed signs of an emerging or developing sense of belief praxis in the face of new situations. Other dominant patterns also emerged. The study found critical objections to the use of fetal stem lines in developing available vaccines and concerns about potential vaccine side effects to the requestor’s body. Trust in the process and a sense of autonomy in participation also were found to be critically import to most requests. [ABSTRACT FROM AUTHOR]

The article provides a detailed account of the Canadian Armed Forces' role in the 2021 Kabul Air Evacuation, known as Operation Aegis. It discusses the challenges faced during the operation, including limited landing slots and strict time constraints at the overcrowded airport. Despite these obstacles, Canadian forces worked closely with their allied partners to maximize the number of evacuees. The conditions on the ground were described as tenuous, chaotic, and desperate, with Canadian military personnel going above and beyond to assist evacuees. The operation involved procuring necessary supplies locally and ensuring the safety and well-being of the evacuees. The Canadian military's mission was driven by the purpose of helping evacuate as many people as possible, providing them with opportunities for education and a better future. [Extracted from the article]

The article provides a comprehensive overview of the Royal Canadian Air Force (RCAF) from its establishment in 1924 to its involvement in World War II. It discusses the initial lack of understanding of the purpose of an air force and the RCAF's focus on civilian tasks. The article highlights the significance of the British Commonwealth Air Training Plan (BCATP) in gaining recognition for the RCAF. It also explores the challenges faced by the RCAF, including limited resources and the integration of Canadian graduates into RAF squadrons. The article concludes by discussing the RCAF's role in various conflicts throughout history, including World War II and the Cold War. It mentions the limitations in the number of RCAF squadrons formed and the challenges of integrating women into the force. Despite these challenges, the RCAF's mission continues into the future. [Extracted from the article]

Air Force Historical Foundation Awards for 2023 Air Command and Staff College: the 2023 award at ACSC went to Mr. Philip R. Povolish Jr., for his paper 'An Analysis of [...]

INTRODUCTION: The diagnosis of gender dysphoria has specific requirements per the psychiatric diagnostic manual. This presentation will elaborate upon these criteria and use an anonymized example patient case as a demonstration. TOPIC: One case representing an example of a gender dysphoria presentation will be discussed. Particular attention will be given to the application of diagnostic criteria for the condition, as well as the childhood and young adult experiences reported by our patient that contributed to the recognition of this condition. This discussion will build on the earlier panel presentations and highlight the ACS' experience as well as observations about trends within the cohort. APPLICATION: The discussion will be applicable primarily to U.S. Air Force flight surgeons and mental health providers. The concepts and process may be interesting to those administering waivers and or treating flyers in other military services and in civil aviation. RESOURCES: 1. American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders: Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision. 2. U.S. Air Force Aeromedical Waiver Guide Learning Objectives 1. The participant will be able to analyze and interpret a case study representing an individual with gender dysphoria, applying the diagnostic criteria to understand their condition. 2. The participant will be able to discuss the childhood and young adult experiences that may contribute to the recognition of gender dysphoria in individuals, using the anonymized case study as an example. [ABSTRACT FROM AUTHOR]

BACKGROUND: Summer 2023 was an unprecedented forest fire season in Canada. Mid-august, the city of Yellowknife, North West Territories, was evacuated due to fast spreading fires threatening the community. 68 inpatients remained in the local hospital, and the closest receiving facility was >1500 km by road. There was no Canadian civilian agency capable of transporting this volume of patients in a short time frame. The Canadian Government requested the assistance of the Canadian Armed Forces to evacuate by air an unknown number of inpatients > 2000 km to the city of Vancouver. OVERVIEW: The Canadian Forces Aeromedical Evacuation (CF AE) flight is based in Trenton, Ontario and has the mandate of providing strategic aeromedical evacuation to CAF members anywhere in the world. Care or transport of civilians is only provided if requested and approved by the Minister of National Defence. The Royal Canadian Air Force (RCAF) does not have dedicated AE aircraft and instead uses a platform of opportunity. The vastness of Canadian geography creates a tyranny of distance, and in this case, the providers and aircraft were located 5000km from the area in need. With careful but quick consideration of aircraft, crew composition and size, equipment, load plan, communication and coordination, a crew was launched for the remaining 39 patients (23 stretcher, 6 wheelchairs, 10 ambulatory). The CC177 departed CYZF with all patients less than 36 hours after the initial request was approved. DISCUSSION: This was the first time the RCAF and CF AE flight conducted a mass civilian hospital evacuation. Serendipitously, these groups had just participated in Mobility Guardian 2023 and had exercised some larger scale, interoperable, unregulated evacuations. Lessons learned for discussion include; importance of a liaison officer and unrestricted comms between sending, transporting and receiving facility; integration of military and civilian care teams; prolonged care requirements to include medication administration and hygiene; ramp access for medical transport and medical teams; and aircraft equipment to facilitate load plan. It is hoped that the lessons learned during this event can be of use to other organizations who may be required to preform a similar task in the future. Learning Objectives 1. The audience will understand planning factors which are of importance during large-scale time-bound aeromedical evacuations. 2. The audience will explore the potential challenges and considerations when integrating military and civilian care teams/facilities for joint missions. [ABSTRACT FROM AUTHOR]