Spectrum Of Threats Research Articles

THE ROLE OF EPITHELIAL β-DEFENSINS AND CATHELICIDINS IN HOST DEFENSE OF THE LUNG

The continuous exposure of the epithelial surface of the conducting airways to inhaled pathogens requires the presence of an efficient innate immune system to prevent infections. The innate immune system of the lung provides protection against a broad spectrum of microbial threats through a variety of effector mechanisms. The antimicrobial peptides and proteins form important elements of this defence system in the lung. Defensins and cathelicidins are the main families of antimicrobial peptides (AMPs) that are present in airway secretions and that are expressed by the airway epithelium. Expression and release of these small (3–5 kDa) cationic peptides is regulated by exposure of epithelial cells to a wide variety of substances, including microbial products, cytokines and growth factors. More recently, also active vitamin D3 has been implicated as a major regulator of AMPs expression. AMPs contribute to host defence through direct antimicrobial activity, as well as by modulating innate and adaptive immunity, and wound repair. Novel insight into the mechanism of action of these peptides and the regulation of their expression may lead to innovative approaches for treatment of infectious and inflammatory lung disorders.

Guest Editorial for the Special Issue on the 2005 IEEE/IFIP Conference on Dependable Systems and Networks, including the Dependable Computing and Communications and Performance and Dependability Symposia

NOW more than ever, dependable computing systems, along with secure networking and communication infrastructures, are essential to critical applications and services. This is due, in particular, to the emergence of very large-scale systems made up of myriads of ever-evolving and often mobile computerized devices with numerous and complex interactions and interdependencies. Moreover, the increasingly broad spectrum of threats—physical or human-made, accidental or malevolent—to these various layers and interfaces adds another difficult facet to the challenge. The people in charge of designing intricate computing systems are concerned with developing and implementing resilient components, architectures, networks, protocols, software algorithms, and applications. In addition, topics related to the assessment of the properties achieved both during the development process and in operation are also critical. Verification (proving and testing) and evaluation, including analytical modeling, simulation, field measurements, and controlled experiments, are necessary for the successful exploitation and monitoring of these systems. This special issue aims to serve researchers, designers, and implementers of dependable and secure systems and infrastructures. It includes a set of papers presented at the Dependable Computing and Communication Symposium (DCCS) and the Performance and Dependability Symposium (PDS) that were part of the sixth edition of the annual IEEE/IFIP Dependable Systems and Networks (DSN) Conference held in Yokohama, Japan, in 2005. The technical program of DSN-2005 included 77 regular papers covering a wide range of relevant issues and showing the depth and breadth of our community’s research efforts. This collection was the result of the tough and thorough selection process that characterizes this conference in both symposia. For DCCS, from the 205 submissions, with contributions originating from 35 countries from all continents, 50 regular papers were accepted by the program committee based on a total of 846 reviews with an average of 4.13 reviews per paper. PDS received 94 submissions from 19 countries from all continents and 27 papers were accepted by the PC based on a total of 435 reviews with an average of 4.63 reviews per paper. Two subcommittees were formed to select a small number of papers from each symposium to form this DSN special issue. We want to thank the members of these subcommittees, chaired by the guest editors: for DCCS, Christian Cachin, Farnam Jahanian, Carl Landwehr, Raimundo Macedo and Nirmal Saxena, and, for PDS, Nuno Neves, Aad van Moorsel, and Markus Siegle. Their dedication in carrying out this selection on a tight schedule was outstanding. Out of a total of 77 regular papers, six papers were selected from DCCS and three from PDS and the authors were invited to submit properly extended versions of their contributions. Each paper went through another two rounds of review by qualified experts, some of them already familiar with these papers because they had been reviewers for DSN and others specifically invited to perform this review. In the end, seven papers successfully went through this selection process and will be archived in TDSC as a sample of the excellent program of DSN-2005. These papers cover a broad subset of the symposia themes. They include contributions on architecting systems, devising procedures and protocols, modeling and measuring systems, covering hardware and software layers, and coping with threats ranging from accidental to malicious faults. IEEE TRANSACTIONS ON DEPENDABLE AND SECURE COMPUTING, VOL. 3, NO. 3, JULY-SEPTEMBER 2006 169

NIH Countermeasures Against Chemical Threats (CounterACT) Research Program

The NIH is taking a leadership role in pursuing the development of new and improved medical countermeasures designed to prevent, diagnose, and treat the conditions caused by potential and existing chemical agents of terrorism. In addition, many of the same chemicals posing a threat as terrorist agents may also be released from transportation and storage facilities by industrial accidents or during a natural disaster. The NIH has developed a comprehensive Countermeasures Against Chemical Threats (CounterACT) Research Network that includes Research Centers of Excellence, individual research projects, Small Business Grants and Contracts, and other programs (see http://www.ninds.nih.gov/funding/research/counterterrorism/index.htm ). The network will conduct basic, translational, and clinical research aimed at the discovery and/or identification of better therapeutic and diagnostic medical countermeasures against chemical threat agents. The overarching goal of this research program is to enhance our diagnostic and treatment response capabilities during an emergency. The civilian chemical threat spectrum now includes chemical warfare agents, toxic industrial chemicals, toxins and other chemicals. Many of the highest priority chemical threat agents target the nervous system and require new and improved neurotherapeutics that can be used as safe and rapid medical countermeasures during a mass casualty situation. Examples of these chemical agents include anticholinesterase nerve “gases” such as sarin or VX, metabolic poisons such as cyanide, and biological neurotoxins such as saxitoxin. The type of research supported within the CounterACT research program includes: (1) mechanistic research to identify targets for therapeutic/diagnostic development, (2) development of in vitro and animal models for efficacy screening of therapeutics and diagnostic tools, (3) efficacy screening of therapeutics/diagnostics using new and validated in vitro and animal models, (4) advanced efficacy studies with appropriate animal models including nonhuman primates, and (5) clinical studies, including trials, when appropriate. Special consideration will be given to research relevant to people who are particularly vulnerable, including the young, the elderly, and individuals with pre-existing medical conditions. Interested parties are encouraged to contact Dr. David A. Jett, via email at jettd@ninds.nih.gov or by telephone at (301) 496-6035 for more information and funding opportunities within the NIH CounterACT research program.

Network-centric emergency response: The challenges of training for a new command and control paradigm

The last two decades have seen technological innovations that have revolutionized the collection and transfer of information, permitting access to and dissemination of massive amounts of data with unprecedented speed and efficiency. These innovations have been incorporated into virtually every aspect of modern society, from personal communications, to commercial and business processes, to governmental function and military operations. The concept of network-centric warfare (NCW) grew out of these new capabilities and has been a prominent topic in strategic and operational discussions in the US military since the late 1990s.In recent years, the concepts behind NCW have been increasingly applied to emergency response, particularly as responders prepare for an increasingly complex threat spectrum in a post-9/11 world. As emergency responders adopt the technological innovations and organizational concepts that enable network-centric operations, attention should be paid to the lessons learned by the US armed forces in the application of the network-centric approach to war-fighting. Emergency operations centers (EOCs), incident command centers (ICCs), and field personnel will require extensive training and experimentation to sort out the impact of this new technology. They must develop protocols and procedures to leverage maximum advantage, while avoiding the undesirable and damaging effects of that technology improperly applied. Because most emergency response organizations lack the vast training resources of the US military, they must be innovative and adaptable in taking advantage of every opportunity to train their personnel in the assimilation of this new technology.

Defense Transformation and the 2005 Quadrennial Defense Review

At the end of the Cold War, America entered a new and unfamiliar global security environment. As the Department of Defense began to alter strategies and plans, it quickly became apparent that changes might have to be made across the defense establishment. This led in 1993 to the Bottom-Up Review, and, starting in 1997, to the Quadrennial Defense Review (QDR) process. As the Department of Defense enters its third QDR this year, it is important to understand how central the QDR has become to the work of the department--and how different this QDR is, compared to its predecessors. With a yearly budget in excess of $400 billion, the Department of Defense is perhaps the largest single bureaucracy in the world. Sheer size, as well as vested interests and old ways of thinking, tend to give large bureaucracies an inertial resistance to change. One of the tasks in the department this year is to ensure that the QDR can instead be an engine of continued transformation. The need to transform our military has elevated the role of the QDR from a tool of periodic refinement to a fulcrum of transition to a post-9/11 world. This article will explore what the QDR has become, how it is being processed, and what the Defense Department hopes it will achieve. The Modern History of US Defense Transformations It is rare in history for institutions at the height of their success to transform themselves in anticipation of new challenges, but the armed forces of the United States have done it before. Looking back at major defense transformations through our history, we can see that periods of concerted national effort to transform the military have tracked a cyclical pattern: New challenges lead the defense establishment to develop new strategies, which in turn leads to investments in capabilities appropriate to that strategy. In the 1930s, faced with the rise of aggressively expansionist regimes in Japan and Europe, the United States needed to prepare for the possibility of a new kind of conflict, and on a huge scale. We devised a strategy of both mass and speed, one that emphasized destroying the enemy's industrial capacity as much as its forces in the field. Accordingly, the United States invested heavily in amphibious warfare, carrier-based air power, a strategic bombing force, and an industrial base to support mechanized warfare. In the nuclear age, faced with a global threat from the Soviet Union, we had to transform the military to integrate nuclear and conventional forces, dramatically increasing its power and scope to maintain a strategy of containment and the capability for massive retaliation. In the 1980s, America embarked on a series of competitive strategies meant to expose fissures in the military establishment and strategic posture of the Soviet Union, in the hopes--successfully as it turned out--of stressing them beyond their breaking point in their competition with the United States. In each of these cases, a new set of strategic problems led to new strategic thinking and then to sweeping transformation in the structure, posture, weapon systems, and tactical doctrines of our military. Since 9/11, the Defense Department has gained sufficient insight into the new problem-set we face that the time is again ripe for new strategic thinking and for transforming the force. The QDR provides a unique lever with which to translate these insights into action. When the Defense Department began its work under a new Administration nearly five years ago, President Bush charged it with preparing the military for the challenges of the 21st century. This was to be no easy task: if we knew anything about those challenges, it was that we didn't know enough about them. Because we can no longer make confident predictions about the specific threats we will face, we must be able to provide for national defense across a broad spectrum of threats. This has required a change in planning methodology, using new tools for thinking about developing needed capabilities. …

Transforming Defense Basic Research Strategy

The US armed forces currently enjoy an unprecedented level of technological superiority across the full spectrum of military threats. These advances were primarily funded through US government and Department of Defense support of basic science and technology throughout the 50 years of relative peace experienced during the Cold War. A long-term investment in research has allowed the military to field key enabling technologies such as radar, jet engines, nuclear weapons, night vision, precision-guided munitions, stealth, the Global Positioning System, unmanned air vehicles, and information management systems that have dramatically changed warfare. Technological superiority will continue to be a cornerstone of our national military strategy. (1) While today's technological edge allows us to dominate the broad spectrum of conflict and win with relatively few casualties, maintaining a technological edge has become a key component of the vision to transform the US joint forces by relying on the development and fielding of high-technology weapons that enable a smaller force to be more effective. (2) The catalyst that created today's generation of technological advances was a post-World War II decision to create a huge national engine of public science. The blueprints of this engine were drafted in a report to President Truman by Vannevar Bush, who was the Director of the Office of Scientific Research and Development. The foundation of Dr. Bush's plan was to fund investigator-initiated projects, largely conducted in academic laboratories, by civilians independent of the military establishment. (3) Under this construct, universities did fundamental research work--the R in R&D. Government laboratories and arsenals would then take some of that research and, with the cooperation of industry, develop it into military technologies. The vision Bush proposed clearly recognized that the applications developed from basic research often appeared many years after the work was initiated, and that there may be no clear benefit realized from much of this work. In the 50 years since the end of World War II, changes have occurred that might call for a major adjustment in our strategy for defense funding of scientific research. The two most important are the end of the Cold War and the emergence of a global technological marketplace. (4) Public funding of basic research for the Department of Defense during the Cold War was successful because it minimized risk by taking maximum advantage of long-term research projects that produced rather mature technologies for development. The Global Positioning System (GPS) is an example of a technology that has given US forces an incredible advantage on the modern battlefield. Research on satellites and a global positioning system began in 1946 after the publication of an article on geo-stationary orbits by physicist Arthur C. Clarke, more widely known for writing 2001: A Space Odyssey. The first GPS satellite was launched in 1978, with the full 24-satellite constellation completed on 9 March 1994. (5) In a way our science and technology capability has acted as an additional form of deterrence against our adversaries. However, in today's fast-paced and dynamic environment, the Department of Defense cannot afford 48 years to research, develop, and deploy critical technologies to the warfighter. Many critical defense technologies are now readily available in the global marketplace. Therefore advanced technology is as readily available to our adversaries and allies alike. This makes the in-house development of new capabilities ever more important. The Department of Defense is relying on an investment in science and technology to provide the foundation for transformational joint warfighting capabilities. However, the DOD has maintained the same basic research infrastructure and funding policies that were developed for the Cold War. In order Lo stay ahead of adversaries with access to technologies available in the global marketplace, the DOD needs to shorten the time-frame from concept to fielding. …

Issues in chemical and biological terrorism.

This manuscript describes the overview presented at the 23rd Annual Meeting of the American College of Toxicology in 2002. Although it is recognized that weapons of mass destruction that can be used against our military and civilian populations include chemical, biological, radiological, and nuclear (CBRN) agents, this overview is limited primarily to chemical and biological (CB) agents. The issues of CB terrorism are discussed in terms of When, What, How, and Who. The US Army has been providing chemical and biological solutions since 1917, and has since 1996 applied these solutions to homeland defense and domestic preparedness. The use of chemical and biological agents as terrorist weapons both in the United States and elsewhere in the world is reviewed. The CB threat spectrum is presented, as is the further categorization of biological threat agents by the Centers for Disease Control and Prevention (CDC). In addition, the CB agents considered to be a potential threat to our water supply are also presented. These are agents that are water soluble, stable, and resistant to water treatment and/or disinfection. The overview concludes with the chronological accomplishments of ECBC since 1917.

Issues in Chemical and Biological Terrorism

This manuscript describes the overview presented at the 23rd Annual Meeting of the American College of Toxicology in 2002. Although it is recognized that weapons of mass destruction that can be used against our military and civilian populations include chemical, biological, radiological, and nuclear (CBRN) agents, this overview is limited primarily to chemical and biological (CB) agents. The issues of CB terrorism are discussed in terms of When, What, How, and Who. The US Army has been providing chemical and biological solutions since 1917, and has since 1996 applied these solutions to homeland defense and domestic preparedness. The use of chemical and biological agents as terrorist weapons both in the United States and elsewhere in the world is reviewed. The CB threat spectrum is presented, as is the further categorization of biological threat agents by the Centers for Disease Control and Prevention (CDC). In addition, the CB agents considered to be a potential threat to our water supply are also presented. These are agents that are water soluble, stable, and resistant to water treatment and/or disinfection. The overview concludes with the chronological accomplishments of ECBC since 1917.

New Challenges in Critical Infrastructures: A US Perspective

The emergence of a larger spectrum of threats – terrorism, sabotage, local conflicts, political unrest, and natural disasters – combined with the growing globalisation of economic activities, makes networks highly vulnerable. Rethinking national vulnerabilities requires the creation and the improvement of long‐term public‐private partnerships. This article discusses the US Presidential initiative launched in 1996 –the first initiative world wide to put these issues on the top‐level agenda– as well as the national structure of developed partnerships. It might constitute a starting point for other countries to develop their own national strategy, adapting it of course to their own national particularities. Terrorist attacks in 2001 show, however, that such an initiative is nothing but a first step in a general process to build preparedness nation wide; America still remains highly vulnerable. I conclude with a few myths that must be confronted to deal more efficiently with these new large‐scale risks at an international level.

Leveraging the nation's anti-bioterrorism investments: foundation efforts to ensure a revitalized public health system.

The emerging potential threats of bioterrorism combined with critical existing epidemics facing the United States call for immediate and urgent attention to the U.S. public health system. The foundation world is helping to answer that call and is sounding the alarm that our health defenses must be able to do "double duty" to protect us from the full spectrum of modern health threats. This Special Report presents a selective sample of recent and ongoing grant activities designed to revitalize and modernize the public health infrastructure, which is vital to protecting the nation's health and ensuring its safety.

The role of neutron based inspection techniques in the post 9/11/01 era

Non-intrusive inspection of objects of all sizes, from luggage to shipping containers and from postal parcels to trucks is a vital component of any national security from aviation to the control of all land and sea ports of entries. The paramount importance of these inspections is more obvious now, in the post 9/11 era, as the spectrum of threats is wider and the probability of occurrence more real. The urgent need for reliable inspection underscores the key attributes they must possess: • High specificity • High sensitivity • Provide automatic decision The technologies being currently employed in the field, such as standard X-ray, X-ray based computed tomography, and trace detection (for luggage), and X-ray or γ-ray based radiography (for containers) are inherently deficient for lacking some or all of these attributes. The neutron based technologies, on the other hand, possess all three. They provide therefore accurate, rapid and automatic detection of a wide array of threats: explosives, chemical agents, nuclear materials and devices, other hazardous materials, drugs, etc. The nuclear based techniques achieve this feat through the production of characteristic elemental gamma rays by nuclear reactions, primarily (n,γ) with thermal neutrons and (n,n ′γ) with fast neutrons. The principles and status of neutron based inspection techniques are reviewed below.

Terrorist use of weapons of mass destruction: How serious is the threat?

This article examines the extent to which terrorist use of nuclear, chemical, and biological weapons poses a tangible threat to international security. In the literature on terrorism and weapons of mass destruction (WMD) some analysts have tended to exaggerate the scope of the threat and assumed that large-scale terrorist acts involving WMD are only 'a matter of time'. In short, there is a tendency among observers to converge on analogous assessments at the higher end of the threat spectrum. In this article I argue that although WMD terrorism remains a real prospect, the ease with which such attacks can be carried out has been exaggerated; acquiring WMD capabilities for delivery against targets is a lot more problematic for terrorists than is generally acknowledged in the literature. However, this is not to say that the possibility of such attacks can (or should) be ruled out. The rise of a 'new' brand of terrorism that operates across transnational networks and whose operations aim to inflict mass casualties, coupled with the destructive threshold crossed on 11 September 2001, mean that terrorist attacks using WMD will continue to be a realistic prospect in the future.

Mass spectrometric identification of toxins of biological origin

The chemical/biological (CB) threat spectrum encompasses a wide range of potential agents including chemical warfare agents, biological warfare agents and toxins of biological origin that fall between these two main agent categories. These proteinaceous and non-proteinaceous toxins, commonly referred to as mid-spectrum agents, range in molecular mass from a few hundred to more than a hundred thousand daltons. The large number of potential candidates as well as the structural diversity of possible mid-spectrum agents makes identification of these compounds a challenge. The NATO defense community has recognized these challenges and has a working group that is developing identification protocols and evaluating methods through a series of international analytical exercises. Identification strategies rely heavily on recent advances that have been made in both mass spectrometry (MS) and liquid chromatography (LC), with LC–MS typically being employed as the primary method for separation/identification. While this paper focuses on the application of these and related instrumental analytical techniques for the identification of mid-spectrum agents, the approach described could be applied in the fields of toxicology, forensic science and environmental analysis. Areas for future research have been identified and application of developed mid-spectrum identification methods to the ongoing biological and toxin weapons convention (BTWC) are anticipated.

Conventional analytical methods for chemical warfare agents

Abstract Analytical methods that are currently used for the detection and identification of chemical warfare agents are reviewed and classified by the number of dimensions of information they provide. Single dimensional sensors target specific compounds or classes of compounds. Although they can be less expensive and more portable than multidimensional sensors, multidimensional sensors detect a broader threat spectrum with greater precision and accuracy. The recommendation for analytical field verification during inspections under the Chemical Weapons Convention (CWC) is to use simple two-dimensional analytical methods, such as gas chromatography (GC) or ion mobility spectrometry (IMS), for on-site screening of chemical weapons (CW) agents or to fully equip a modern, mobile analytical laboratory located in an airplane, which can be moved rapidly throughout the world to each inspection site and provide high-quality analytical data on-site.

Root-mean-square miss distance of proportional navigation missile against sinusoidal target

The performance of a proportional navigation homing missile against a target performing a sinusoidal weave maneuver is evaluated. The missile's effectiveness is measured in terms of the root-mean-square miss distance over a set of engagements in which the initial phase of the target weave is uniformly distributed. Closed form solutions for the root-mean-square miss are derived for the case where the missile guidance system is modeled by a first-order lag and the lateral acceleration is unlimited. The analysis is then extended to include the effects of acceleration saturation and higher order missile dynamics. Comparisons are made between a first-order and a fifth-order guidance system, and the root-mean-square miss is determined numerically as a function of the interceptor's effective navigation gain, time constant and acceleration limit, and the target's weave amplitude and frequency. UTURE homing interceptor missiles will face new and unique challenges as the sophistication of the threat spectrum in- creases. Engagements against air targets can occur at both very low and very high altitudes, with the threats accidentally or intentionally performing weaving or spiraling maneuvers during their midcourse and terminal phases.14 The lateral displacement, acceleration ca- pability, and weave frequency of the target maneuver can greatly enhance the threat's ability to survive a counterattack. To counter this, the defensive missile must have sufficient lateral acceleration, guidance system time constant, and terminal homing time to achieve a high probability of intercept. Whereas the per- formance of the interceptor will be influenced by many scenario- dependent factors,58 a major consideration will be the fundamental response of the proportional navigation (PN) guidance system to the postulated target weave motion.9'10 In the general case, the target dynamics may involve arbitrary periodic motion in three dimensions. A useful starting point for analysis, however, is the response of the PN homing system to a single plane sinusoidal maneuver of constant amplitude and fre- quency. The phase angle of target weave, which is associated with initial conditions at the start of the missile's terminal guidance, can be treated as a random variable, uniformly distributed between 0 and 2n over a set of engagements. The missile's dynamics are approxi- mated by a simple first-order transfer function, and unlimited lateral acceleration capability is assumed. The miss distance can then be parameterized in terms of the effective PN navigation gain N, the missile time constant T, and the amplitude AT and frequency co of the target weave. This paper focuses on root-mean-square (rms) miss distance as a recommended measure of effectiveness in analyzing missile perfor- mance against weaving targets. This measure allows uncertainties in target phase characteristics to be accounted for in the terminal per- formance results. The weaving target problem was first addressed by Chadwick, 9 who determined analytical expressions for the rms miss distance of the single lag PN missile for values of N =2 and 3. Zarchan 10 employed adjoint theory and transfer function tech- niques to determine formulas for the peak miss distance against a weaving target for values of N between 3 and 6. The present paper derives general closed-form expressions for the rms miss distance against a sinusoidal target. New results are obtained for arbitrary

Israel's Unauthorized Arms Transfers

Israel confronts a spectrum of security threats. Given that harsh reality and America`s firm commitment to the Jewish state as reiterated by successive presidents, Israel requires, and rightly receives, unique attention and support from the United States (U.S). Indeed, Israel`s welfare, even survival, is dependent on its `special` relationship with Washington. Thus far, U.S.-Israel ties have weathered America`s post-Cold War retrenchment in world affairs. Israel retains its customary level of foreign aid, for example, even as the overall foreign assistance budget shrinks. Yet below the surface, the relationship is threatened by Israel`s repeated contraventions of American law. Evidence shows that Israel has systematically circumvented U.S. restrictions on the re-export of U.S. defense products, components, and technical data. Other countries have been caught evading U.S. re-export controls, but Israel`s case appears unique. The author examines the details and implications of the Israel transgressions.

Conservation of Aquatic Insects: Worldwide Crisis or Localized Threats?

An overview is presented on the current worldwide status of aquatic insect conservation. Despite extensive habitat destruction or modification, aquatic insects as a whole do not appear to have suffered as great a proportional loss of species over the last century as members of other groups. In North America, for example, only 204 species are considered at risk out of a total fauna of over 10,000 species, and no species has been documented as having gone extinct. Even so, aquatic insect diversity is subject to a broad spectrum of threats, including chemical pollution of waters from industry and agriculture, physical destruction of habitat from impoundments or drainage, and introduction of alien aquatic biota, primarily sport or aquarium fishes. Adequate legislation exists in the United States and Europe to provide protection to aquatic insect taxa at risk, but the implementation of this legislation is often hampered by a lack of taxonomic and distributional knowledge, and by a concentration of recovery efforts on more highly visible vertebrate taxa. The case of the Ash Meadows Naucorid, the only aquatic species currently protected under the Endangered Species Act, is examined in detail. It is concluded that the listing of this species has had no discernable effect in halting its population decline, partly due to the fact that recovery efforts for endangered fishes have proven deleterious to the insect. It is recommended that future listing efforts be conducted in the context of national biological surveys, and that an ecosystem rather than single species approach be applied to aquatic conservation efforts.

Gigaflop (billion floating point operations per second) performance for computational electromagnetics

Accurate and rapid evaluation of radar signature for alternative aircraft/store configurations would be of substantial benefit in the evolution of integrated designs that meet radar cross-section (RCS) requirements across the threat spectrum. Finite-volume time domain methods offer the possibility of modeling the whole aircraft, including penetrable regions and stores, at longer wavelengths on today's gigaflop supercomputers and at typical airborne radar wavelengths on the teraflop computers of tomorrow. A structured-grid finite-volume time domain computational fluid dynamics (CFD)-based RCS code has been developed at the Rockwell Science Center, and this code incorporates modeling techniques for general radar absorbing materials and structures. Using this work as a base, the goal of the CFD-based CEM effort is to define, implement and evalute various code development issues suitable for rapid prototype signature prediction.

Wing size vs radome compensation in aerodynamically controlled radar homing missiles

The aerodynamic configuration of a homing missile is usually based on aerodynamic studies against the spectrum of threats to be engaged. The most aerodynamically efficient missile is often selected from single fly-out studies not specifically related to guidance. This paper delineates a tradeoff related to guidance system performance that can affect the aerodynamic configuration. This tradeoff is between radome compensation and wing size. It is shown that radome compensation can be used to reduce wing size, and thereby a missile's drag and weight. A quantitative example is presented for a representative design.

A Framework for Evaluating the Effectiveness of Nuclear Safeguards Systems

This paper describes an analytical tool for evaluating the effectiveness of safeguards that protect special nuclear material (SNM). The tool quantifies the effectiveness using several measures, including probabilities and expected times to detect and respond to malevolent attempts against the facility. These measures are computed for a spectrum of threats involving outsiders, insiders, collusion, falsification, and deceit. Overall system effectiveness is judged using performance indices aggregated over all threats. These indices can be used by designers and regulators when comparing costs and benefits of various safeguards. The framework is demonstrated with an example in which we assess vulnerabilities of a safeguards system and identify cost-effective design modifications.