288 research outputs found
Pressure Systems Energy Release Protection (Gas Pressurized Systems)
A survey of studies into hazards associated with closed or pressurized system rupture and preliminary guidelines for the performance design of primary, secondary, and protective receptors of these hazards are provided. The hazards discussed in the survey are: blast, fragments, ground motion, heat radiation, biological, and chemical. Performance guidelines for receptors are limited to pressurized systems that contain inert gas. The performance guidelines for protection against the remaining unaddressed degenerative hazards are to be covered in another study
DRONE DELIVERY OF CBNRECy – DEW WEAPONS Emerging Threats of Mini-Weapons of Mass Destruction and Disruption (WMDD)
Drone Delivery of CBNRECy – DEW Weapons: Emerging Threats of Mini-Weapons of Mass Destruction and Disruption (WMDD) is our sixth textbook in a series covering the world of UASs and UUVs. Our textbook takes on a whole new purview for UAS / CUAS/ UUV (drones) – how they can be used to deploy Weapons of Mass Destruction and Deception against CBRNE and civilian targets of opportunity. We are concerned with the future use of these inexpensive devices and their availability to maleficent actors. Our work suggests that UASs in air and underwater UUVs will be the future of military and civilian terrorist operations. UAS / UUVs can deliver a huge punch for a low investment and minimize human casualties.https://newprairiepress.org/ebooks/1046/thumbnail.jp
Aeronautical Engineering: A continuing bibliography
This bibliography lists 347 reports, articles and other documents introduced into the scientific and technical information system. Documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated compounds, equipment, and systems are included. Research and development in aerodynamics, aeronautics and ground support equipment for aeronautical vehicles are also included
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SDI: Technology, Survivability, and Software
This report is the unclassified version of a classified document delivered to Congress at the end of August 1987. In attempting to reach agreement with the Department of Defense on what information could be included in an unclassified report, OTA found the wheels of bureaucracy to turn very slowly—when they turned at all. Only through the active intervention of the Strategic Defense Initiative Organization, beginning in late in November 1987, and extending to the end of March, 1988, was a partial resolution of the problem achieved
Aeronautical Engineering: A continuing bibliography with indexes
This bibliography lists 512 reports, articles and other documents introduced into the NASA scientific and technical information system in April 1982
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Defense Technical Information Center thesaurus
This DTIC Thesaurus provides a basic multidisciplinary subject term vocabulary used by DTIC to index and retrieve scientific and technical information from its various data bases and to aid DTIC`s users in their information storage and retrieval operations. It includes an alphabetical posting term display, a hierarchy display, and a Keywork Out of Context (KWOC) display
A novel dual-spin actuation mechanism for small calibre, spin stabilised, guided projectiles
© Cranfield University 2022. All rights reserved. No part of this publication may be reproduced without the
written permission of the author and copyright holderSmall calibre projectiles are spin-stabilised to increase ballistic stability, often at
high frequencies. Due to hardware limitations, conventional actuators and meth ods are unable to provide satisfactory control at such high frequencies. With the reduced
volume for control hardware and increased financial cost, incorporating traditional guid ance methods into small-calibre projectiles is inherently difficult. This work presents a novel method of projectile control which addresses these issues and conducts a systems
level analysis of the underlying actuation mechanism. The design is shown to be a viable
alternative to traditional control methods, Firstly, a 7 Degree-of-Freedom (DoF) dynamic model is created for dual-spin pro jectiles, including aerodynamic coefficients. The stability of dual-spin projectiles, gov erned by the gyroscopic and dynamic stability factors is given, discussed and unified across
available literature. The model is implemented in a Matlab/Simulink simulation environ ment, which is in turn validated against a range of academic literature and experimental
test data. The novel design and fundamental operating principle are presented. The actuation
mechanism (AM) is then mathematically formulated from both a velocity change (∆V )
and a lateral acceleration (a˜) perspective. A set of axioms are declared and verified using
the 7-DoF model, showing that the inherently discrete system behaviour can be controlled
continuously via these control variables, ∆V or a˜. Control state switching is simplified to
be instantaneous, then expanded to be generically characterised by an arbitrarily complex
mathematical function. A detailed investigation, parametric analysis and sensitivity study
is undertaken to understand the system behaviour.
A Monte Carlo procedure is described, which is used to compare the correction cap abilities of different guidance laws (GLs). A bespoke Zero-Effort-Miss (ZEM) based GLis synthesised from the mathematical formulation of the AM, with innately more know ledge of the system behaviour, which allows superior error correction. This bespoke GL
is discussed in detail, a parametric study is undertaken, and both the GL parameters and
PID controller gains are optimised using a genetic algorithm. Artificial Intelligence (AI)
Reinforcement learning methods are used to emulate a GL, as well as controlling the AM
and operating as a GL, simultaneously.
The novel GLs are compared against a traditional proportional navigation GL in a
nominal system and all GLs were able to control the AMs, reducing the miss distance to a
satisfactory margin. The ZEM-based GL provided superior correction to the AI GL, which
in turn provided superior correction over proportional navigation. Example CAD models
are shown, and the stability analysis is conducted on the geometry. The CAD model is
then used in CFD simulations to determine aerodynamic coefficients for use in the 7-DoF
dynamic model. The novel control method was able to reduce the 95% dispersion diameter
of a traditional ballistic 7.62mm projectile from 70mm to 33mm. Statistical data analysis
showed there was no significant correlation or bias present in either the nominal or 7-DoF
dispersion patterns. This project is co-sponsored by BAE Systems and ESPRC (ref. 1700064). The con tents of this thesis are covered by patent applications GB2011850.1, GB 2106035.5 and
EP 20275128.5. Two papers are currently published (DOI: 10.1016/j.dt.2019.06.003, the
second DOI is pending) and one is undergoing peer review..PH
Department of Defense Dictionary of Military and Associated Terms
The Joint Publication 1-02, Department of Defense Dictionary of Military and Associated Terms sets forth standard US military and associated terminology to encompass the joint activity of the Armed Forces of the United States. These military and associated terms, together with their definitions, constitute approved Department of Defense (DOD) terminology for general use by all DOD components
Anti-UAV defense for ground forces and hypervelocity rocket lethality models
This thesis analyzes the threat that unmanned aerial vehicles (UAVs) pose to U.S. ground forces. The operational environment in which both lethal and non-lethal UAVs may be encountered by friendly surface forces is examined to determine the elements of UAV operation which may be exploited in defense against UAVs. Two probability models of the air defense endgame are developed to examine the potential lethality of hypervelocity rocket anti-UAV weapons. These models are used to determine the detonation distance which maximizes the probability that a single hypervelocity rocket kills a UAV. Data used in this study are synthetic to prevent disclosure of classified and proprietary information and allow wider distribution of this thesis.http://archive.org/details/antiuavdefensefo1094530603Lieutenant, United States NavyApproved for public release; distribution is unlimited
Aeronautical Engineering: A continuing bibliography with indexes (supplement 177)
This bibliography lists 469 reports, articles and other documents introduced into the NASA scientific and technical information system in July 1984
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