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An Information Visualization Solution For The Analysis Of The Afm Simulation Output Data, Stuart H. Kurkowski Mar 2000

An Information Visualization Solution For The Analysis Of The Afm Simulation Output Data, Stuart H. Kurkowski

Theses and Dissertations

With the advancement of computer hardware and software computer simulations are now able to run faster and track more elements than ever before burdening the analyst with more and more data to analyze. Air Mobility Command's (AMC) Airlift Flow Model (AFM) is the Air Force's logistics simulator that simulates multi-day mobility scenarios in a matter of minutes producing megabytes of output data. Because the analysts' needs for summaries, trends, and comparisons of the data have surpassed the capabilities of current desktop spreadsheet analysis techniques new tools are needed.

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A Formal Methodology And Technique For Verifying Communication Protocols In A Multi-Agent Environment, Timothy H. Lacey Mar 2000

A Formal Methodology And Technique For Verifying Communication Protocols In A Multi-Agent Environment, Timothy H. Lacey

Theses and Dissertations

As network bandwidth increases, distributed applications are becoming increasingly prevalent. Systems using these applications are very complicated to build and must be dependable. Software agents are ideal for breaking complicated problems into manageable subtasks. Agent conversations, a series of messages passed between agents, are the cornerstone of multi-agent systems and must be deemed correct before being placed into service. The purpose of this research was to develop a formal methodology and technique to verify that the communication protocols defined in a multi-agent environment were valid. This was accomplished by examining agent conversations before deploying the system. An additional goal of …

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Toxicity Of Tolyltriazole To Bacillus Microorganisms, Christopher J. Leonard Mar 2000

Toxicity Of Tolyltriazole To Bacillus Microorganisms, Christopher J. Leonard

Theses and Dissertations

The safety of air travel in cold weather depends upon the use of aircraft deicing fluids (ADAF). The environmental and toxic effects of the ADAF component tolyltriazole are not well understood. Tolyltriazole is a potential human carcinogen and has exhibited microbial toxicity in Microtox test. This research used two methods to investigate the toxicity of tolyltriazole on bacillus shaped microorganisms. The first method compared the dissolved oxygen uptake of microcosms exposed to varying concentrations of tolyltriazole. When exposed to 1000 ppm tolyltriazole, all isolated species showed inhibition in respiration. There was no evidence that tolyltriazole at

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An Intelligent User Interface To Support Air Force Weather Product Generation And Automated Metrics, Darryl N. Leon Mar 2000

An Intelligent User Interface To Support Air Force Weather Product Generation And Automated Metrics, Darryl N. Leon

Theses and Dissertations

Air Force pilots require dependable weather reports so they may avoid unsafe flying conditions. In order to better gauge the accuracy of its weather products, Air Force Weather has established the requirement for an Air Force-wide automated weather metrics program. Under the guidelines for this program, forecasts will automatically be compared to observed weather to determine their accuracy. Statistics will be collected in the hopes of determining forecast error trends that can be corrected through education and training. In order for the statistical data produced by such a program to draw reliable conclusions about forecast accuracy, however, the correct format …

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Using Simulation To Model An Army Recruiting Station With Seasonality Effects, David C. Longhorn Mar 2000

Using Simulation To Model An Army Recruiting Station With Seasonality Effects, David C. Longhorn

Theses and Dissertations

One of the toughest jobs in the Army is that of the recruiter. Recruiters are tasked with the awesome job of convincing young men and women to lay down their lives and freedoms for their country, and oftentimes for less money than can be earned in the safer environment of America's booming economy. Recruiters face enormous pressure from commanders to meet the mandated Army manning levels set each year by Congress. As the Army begins the 21st century, it is faced with having to support an increasing number of deployments with fewer soldiers. Soldiers face long and difficult days with …

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Formal Object State Model Transformations For Automated Agent System Synthesis, David W. Marsh Mar 2000

Formal Object State Model Transformations For Automated Agent System Synthesis, David W. Marsh

Theses and Dissertations

Automated agent system synthesis is the process of generating code from a requirements specification with appropriate inputs from the software engineer. Object-oriented (OO) specifications are frequently used to model intelligent software agent systems and software requirements in general; formal representations capture precisely the intentions of the specifier. Portions of OO specifications can be classified as the structural, functional, and state (or dynamic) models; major strides have been taken in the development of transformations for creating code from formal OO specifications, specifically the structural and functional aspects, and are captured within the AFIT Wide-Spectrum Object Modeling Environment (AWSOME). This research creates …

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Space Range Scheduling And The Lean Aerospace Initiative (Lai), Alan M. Matuszak Mar 2000

Space Range Scheduling And The Lean Aerospace Initiative (Lai), Alan M. Matuszak

Theses and Dissertations

This study describes how lean principles and thinking can be applied to space range operations. The "lean" concepts of the right thing, right place, and the right time are applicable and relevant to this study. The basis for the lean concepts and principles considered is the Lean Aerospace Initiative (LAI). The LAI originated from the International Motor Vehicle Program (IMVP) that was conducted by a team from the Massachusetts Institute of Technology (MIT). The LAI is a collaborative research program involving government, industry, labor, and academia (primarily MIT). The partnership began in 1993 through support of the U.S. Air Force …

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Optical Investigation Of Molecular Beam Epitaxy AlXGa1-XN To Determine Material Quality, Judith L. Mcfall Mar 2000

Optical Investigation Of Molecular Beam Epitaxy AlXGa1-XN To Determine Material Quality, Judith L. Mcfall

Theses and Dissertations

The purpose of this research was to determine the quality of AIGaN samples with various mole fractions of aluminum doped with silicon. The samples utilized for this study were composed of an AIN buffer layer sandwiched between the sapphire substrate and AIGaN epilayer grown by molecular beam epitaxy (MBE). Cathodoluminescence (CL) and photoluminescence (PL) were employed to determine the mole fraction of aluminum in each sample. These techniques also gave insight into the material's nonuniformity, defects, and impurities. CL was run at 4 different beam energies (2,5,10, & 15 keV) with four different currents (1,10,50, & 90 µA) for the …

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Investigation Into The Adaptation Of A Steam Injector For Use On A Liquid Rocket Engine, Charles B. Mcfarland Mar 2000

Investigation Into The Adaptation Of A Steam Injector For Use On A Liquid Rocket Engine, Charles B. Mcfarland

Theses and Dissertations

This thesis investigated the properties of a steam injector to see if the concept might be suitable for use on a liquid rocket engine. A steam injector is a device developed in the 1850's to inject feedwater into the boiler on a steam locomotive without any moving parts. The injectors uses a small portion of the steam generated in the boiler to increase the pressure of the feedwater to a level high than the pressure in the boiler. Previous experiments claim that condensation of steam to water was necessary for an injector to work. This experiment tested injection without condensation …

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Mechanics Of A Functionally-Graded Titanium Matrix Composite, G. Brandt Miller Mar 2000

Mechanics Of A Functionally-Graded Titanium Matrix Composite, G. Brandt Miller

Theses and Dissertations

Functionally-graded Titanium Matrix Composites, (F/G TMCs) combine the ideal properties of titanium matrix composites with the more practical machining qualities of monolithic (unreinforced) alloy. This material shows great promise in application to aerospace structural components - even in parts whose design requirements have defied the use of composite materials in the past. Successful implementation of such a material would lead to enhanced aircraft performance. However, the basic properties of a functionally-graded titanium matrix composite need to be investigated. The composite/alloy transition region, or joint area, may be less strong than its constituents and therefore determine the overall performance of the …

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Toxicity Of Tolyltriazole To Gram-Positive Coccus Microorganisms, Heather L. Mitchell Mar 2000

Toxicity Of Tolyltriazole To Gram-Positive Coccus Microorganisms, Heather L. Mitchell

Theses and Dissertations

Maintaining safe flight operations, military and civilian, in cold weather requires the use of de-icing fluids. Glycols, the primary component of de-icers, have been extensively studied. Water and additives such as corrosion inhibitors and other performance enhancing chemicals make up the remaining portion of de-icing fluids. Little research has been conducted on the additives, but several are suspected toxins to microorganisms, therefore the EPA regulates the disposal of spent de-icing fluids. Tolyltriazole, a corrosion inhibitor found in de-icing fluids, is a suspected human carcinogen. It is also known to be moderately toxic to microorganisms based on Microtox results. The purpose …

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A Method Of Focusing The Attention Of The Decision-Maker On Uncertain Information, John F. Moesner Iv Mar 2000

A Method Of Focusing The Attention Of The Decision-Maker On Uncertain Information, John F. Moesner Iv

Theses and Dissertations

Military decision-makers need to be able to synthesize large amounts of information quickly and make accurate and timely decisions. However, all too often, when a decision-maker is bombarded with important information that has an uncertainty associated with it, that information is often neglected. One method of dealing with this type of information overload is through proper data orientation. By reducing the clutter of irrelevant information, the proportions of useful and relevant data can be increased. At the same time, the attention of the decision-maker is directed to the critical tasks or centers of gravity. The WATCHDOG Decision Support Tool is …

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Chromate Dissociation From Primer Paint In Simulated Lung Fluid, Tiffany J. R. Morgan Mar 2000

Chromate Dissociation From Primer Paint In Simulated Lung Fluid, Tiffany J. R. Morgan

Theses and Dissertations

OSHA has proposed a new strontium chromate exposure standard that would potentially cause Air Force paint facilities to be in violation of the proposed standard if adopted. This proposed reduction make the continued use of chromate containing primer paints very difficult. There is currently no acceptable replacements for chromate containing primer paints on AF aircraft. This study suggests that paint particles with chromate bound in primer paint may be unavailable for bodily absorption if inhaled and a reduced standard for painting applications may be unnecessary. Primer paint overspray was collected into simulated lung fluid (SLF) and allowed 6 hr, 24 …

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Temperature Determination In An I2 Gas Using Dopper-Limited Saturation Spectroscopy, James W. Myers Jr. Mar 2000

Temperature Determination In An I2 Gas Using Dopper-Limited Saturation Spectroscopy, James W. Myers Jr.

Theses and Dissertations

Saturation spectroscopy techniques were used to demonstrate the ability to make spatially resolved temperature measurements by exploiting the B3 ∏(O+u) - X1 Σ ;(O+g) electronic transition in molecular iodine (I2). Doppler-free saturation spectroscopy measurements resulted in hyperfine spectral profiles for the P(7O) 17-1 and P(53) 19-2 ro-vibrational transitions between the electronic levels. Doppler-limited saturation spectroscopy, an adaptation of the Doppler-free technique in which beams propagate in the same direction and cross within the gas sample, allowed for the measurement of spatially resolved Doppler profiles for the same transitions. The profiles were measured …

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Effects Of Jamming On Radars, Ahmet Okuyucu Mar 2000

Effects Of Jamming On Radars, Ahmet Okuyucu

Theses and Dissertations

Although jamming of radars has been in vogue for nearly 50 years there appears to be no comprehensive report on the subject matter. The purpose of this research is to fill this gap. The methodology consisted of analysis, simulation, and where feasible experimental demonstrations. Experimental equipment consisted of a digital noise generator whose output was used to modulate a high frequency carrier in various fashions. The modulated output was fed into a very sensitive super-heterodyne receiver whose Intermediate frequency (IF) bandwidth could be varied from tens of Hz to mega Hz range. The detected output was displayed on a sampling …

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Collection Of Detonation Signatures And Characterization Of Spectral Features, Jay A. Orson Mar 2000

Collection Of Detonation Signatures And Characterization Of Spectral Features, Jay A. Orson

Theses and Dissertations

The remote observations of the temporal and spectral characteristics of the infrared (IR) emissions from exploding ordnance have been correlated with explosion conditions. A Bomem MR-154 Fourier Transform Interferometer with two detectors, InSb and HgCdTe, and a 75 mrad telescope was used to record spectra in the 1.3 - 20 µm range. Data was collected at spectral resolutions of 16 cm-1 and 4 cm-1 and temporal resolutions of 0.045 s and 0.123 s respectively. Two field tests were conducted: (1) a set of dynamic drop explosions and (2) a series of static detonations. In most events, the temporal …

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Determining The Horizontal Distance Distribution Of Cloud-To-Ground Lightning, Tamara L. Parsons Mar 2000

Determining The Horizontal Distance Distribution Of Cloud-To-Ground Lightning, Tamara L. Parsons

Theses and Dissertations

This research effort attempted to quantify what constitutes a safe distance when lightning is present. The method used in this research project groups lightning flashes into clusters using spatial and temporal constraints. However, not all flashes meet the time and distance criteria for clustering and remained outside of tile grouped flashes and as such are identified as isolated flashes. These isolated flashes are outliers in the data set, but are precisely the flashes that prove most dangerous. For this reason not only were the distances between each flash and cluster center studied, but also the distances between each isolated flash …

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Dynamic Route Replanning And Retasking Of Unmanned Aerial Reconnaissance Vehicles, David E. Pritchard Mar 2000

Dynamic Route Replanning And Retasking Of Unmanned Aerial Reconnaissance Vehicles, David E. Pritchard

Theses and Dissertations

Many common operational situations in High Altitude Endurance (HAE) UAV reconnaissance necessitate more direct human involvement in the aircraft control process than is currently acknowledged or allowed. The In-Flight Replanning System (IFRS) is developed as a notional solution, with the Global Hawk HAE UAV as the reconnaissance system model. Problematic scenarios for current in-flight mission replanning systems are presented and revisited with the IFRS, demonstrating improved replanning results.

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Active Multispectral Bidirectional Reflectance Distribution Function Measurement System, Mark J. Proctor Mar 2000

Active Multispectral Bidirectional Reflectance Distribution Function Measurement System, Mark J. Proctor

Theses and Dissertations

Today's highly technical battlefield environment dictates the need for a method of standoff target identification, which reduces risk to personnel and equipment. It is widely known that a given material will react differently to incident radiation than a dissimilar material. Certain materials may respond specularly while others tend to be diffuse. By measuring these responses, materials can be identified by comparison with a known database. One method of building such a database for target recognition is by employing an active multi spectral bidirectional reflectance distribution function (BRDF) measurement system. In the following text, such a system is developed and tested …

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A Validation Assessment Of The Storm Air-To-Air Prototype Algorithm, David M. Pugh Mar 2000

A Validation Assessment Of The Storm Air-To-Air Prototype Algorithm, David M. Pugh

Theses and Dissertations

A validation assessment of the new STORM air-to-air prototype algorithm is accomplished using structural and output validation techniques. In the structural validation phase, the algorithms, code, and assumptions are evaluated to determine if the implementation of the model will match the intent of the designers. The components of the algorithm are compared to its predecessor, THUNDER, to evaluate if the prototype nnproves upon the weaknesses of THUNDER. In the output validation phase, the results of the model are evaluated to determine the extent to which the implementation of the model matches expected outcomes. Sensitivity analysis is presented to provide insight …

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Knowledge Base Support For Design And Synthesis Of Multi-Agent Systems, Marc J. Raphael Mar 2000

Knowledge Base Support For Design And Synthesis Of Multi-Agent Systems, Marc J. Raphael

Theses and Dissertations

AgentTool is an AFIT-produced, AFOSR-sponsored multi-agent system (MAS) development tool intended for production of MASs that meet military requirements. This research focuses on enabling MAS design and synthesis tools like agentTool to store, retrieve, and filter persistent, reusable, and reliable agent domain knowledge. This "enabling" is vital if such tools are expected to produce consistent, maintainable, and verifiable agent applications on short timetables. Enabling requires: 1) modeling the agent knowledge domain, 2) designing and employing a persistent knowledge base, and 3) bridging that domain model to the knowledge base with an extensible domain interchange grammar. The achieved interchange grammar, called …

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Timing Of Thunderstorm Occurrence For Cape Canaveral, Florida, Thomas G. Renwick Mar 2000

Timing Of Thunderstorm Occurrence For Cape Canaveral, Florida, Thomas G. Renwick

Theses and Dissertations

This research is concerned with improving an existing algorithm to accurately forecast thunderstorm starting times for Cape Canaveral, Florida. This was accomplished by investigating different linear regression techniques than those used in the existing algorithm. The result is three new thunderstorm start time algorithms. The forecast start times of these new algorithms were then compared to actual thunderstorm start times to determine which method produced the most accurate results. The average thunderstorm starting time was also calculated from the data. This time was also compared to actual thunderstorm starting time. Upon examination of the various start times produced, it was …

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Nonuniformly Spaced Array Elements, Daniel R. Richards Jr. Mar 2000

Nonuniformly Spaced Array Elements, Daniel R. Richards Jr.

Theses and Dissertations

This thesis provides a method to reduce physical resource requirements along with cost reduction in Space Based Radar (SBR) platforms, and provides a rule of thumb for randomization effects on arrays. A trend analysis is performed on 4, 8, 12, and 16 square meter arrays. Three aperiodic thinning approaches are examined. They are an equal current density element distribution, a random periodic grid of elements, and random element distribution based a peak sidelobe indicator. According to the metrics used, the statistical and deterministic array thinning approaches performed best for these small arrays. However, the statistical arrays have a scan angle …

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A Component Based Approach To Agent Specification, David J. Robinson Mar 2000

A Component Based Approach To Agent Specification, David J. Robinson

Theses and Dissertations

The Air Force, as well as all of industry, is currently faced with the problem of having to produce larger and more complex software systems that run efficiently and reliably as well as being extensible and maintainable. This research addresses this problem by developing a knowledge representation language that can be used to unambiguously specify and design software systems in a verifiable, efficient, and understandable manner. The language is a combination of object-oriented and component-based methodologies and makes use of both graphics and text to represent information. Although designed for the development of any type of software system, the language …

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Atmospheric Temperature Profiles By Ground-Based Infrared Spectrometer Measurements, Jon M. Saul Mar 2000

Atmospheric Temperature Profiles By Ground-Based Infrared Spectrometer Measurements, Jon M. Saul

Theses and Dissertations

A method to recover atmospheric temperature profiles using a ground-based Fourier Transform Infrared spectrometer was investigated. The method used a difference form of the radiative transfer equation, a Bomem MR series Fourier Transform Infrared Spectrometer to collect atmospheric radiance values, and the Phillips Laboratory Expert- assisted User Software (PLEXUS) atmospheric radiance model, to recover an atmospheric temperature profile. The method researched uses radiance values from both the spectrometer measurements and the atmospheric model, along with kernel functions calculated by the atmospheric model as input to a difference form of the radiation transfer equation. From this the change in brightness temperatures …

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Investigation Of Conformal High-Impedance Ground Planes, Michael A. Saville Mar 2000

Investigation Of Conformal High-Impedance Ground Planes, Michael A. Saville

Theses and Dissertations

Applique antennas are a long range vision for military vehicles because they are lighter, quicker to replace, less expensive, and can have better performance than conventional antennas. Two newly reported high-impedance ground planes have potential to begin the realization of the applique antenna vision and each is investigated for use with thin conformal antenna structures. Bistatic reflection measurements completely characterize the high-impedance region of planar, thumbtack high-impedance ground planes, and periodic moment method models validate the measurement results. Rigorous planar and conformal surface wave coupling measurements clarity the reported photonic band gap behavior of the thumbtack high-impedance ground plane, and …

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Computational Fluid Dynamics Testing For Drag Reduction Of An Aircraft Laser Turret, Gregory J. Schwabacher Mar 2000

Computational Fluid Dynamics Testing For Drag Reduction Of An Aircraft Laser Turret, Gregory J. Schwabacher

Theses and Dissertations

A computational study was conducted on the use of aft-mounted fairings for passive drag reduction on a sphere at Re=866,000. The sphere dimensions and operating Reynolds number were selected to approximate the flow around a proposed aircraft laser turret for which experimental data was available. To establish the validity of the computational model, flow predictions were compared to sphere data available in the open literature. The model, exercised in both the laminar and turbulent modes, showed good agreement with the published data. Two proposed laser turret fairings were then evaluated computationally: a large fairing (beginning at 49.5 degrees past the …

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Mission Route Planning With Multiple Aircraft & Targets Using Parallel A* Algorithm, Ergin Sezer Mar 2000

Mission Route Planning With Multiple Aircraft & Targets Using Parallel A* Algorithm, Ergin Sezer

Theses and Dissertations

The general Mission Route Planning (MRP) Problem is the process of selecting an aircraft flight path in order to fly from a starting point through defended terrain to target(s), and return to a safe destination. MRP is a three-dimensional, multi-criteria path search. Planning of aircraft routes involves an elaborate search through numerous possibilities, which can severely task the resources of the system being used to compute the routes. Operational systems can take up to a day to arrive at a solution due to the combinatorial nature of the problem, which is not acceptable, because time is critical in aviation. Also, …

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Mixed Layer Height Estimates – A Statistical Analysis Of Algorithm Performance, Lisa C. Shoemaker Mar 2000

Mixed Layer Height Estimates – A Statistical Analysis Of Algorithm Performance, Lisa C. Shoemaker

Theses and Dissertations

The Air Force Technical Applications Center (AFTAC) conducts dispersion transport modeling as part of their mission support for the United States Atomic Energy Detection System. Part of that modeling effort requires knowledge of the height of the mixed layer in the lower atmosphere to determine the vertical extent through which particulates can be distributed. The mixed layer can be estimated by analyzing atmospheric profiles of parameters obtained from observations (e.g., upper air soundings) or atmospheric models. Six mixed layer algorithms were evaluated: Gradient Richardson Number (RICH), Potential Temperature (POTEMP), Potential Instability Mixing Depth (PIMIX), and three variations of the PIMIX …

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Leontief Metamodeling For Military Strategic Effects, Anthony W. Snodgrass Mar 2000

Leontief Metamodeling For Military Strategic Effects, Anthony W. Snodgrass

Theses and Dissertations

In this research, we propose and demonstrate an approach to incorporate currently un-modeled interactions into an existing or a new combat model or simulation. We apply the Leontief Input-Output model, which is a macro-economic model that measures the interactions between major industrial sectors of an economy, as a metamodel that periodically assesses the status of various combat units and support functions. If needed resources are insufficient, appropriate degrades are input into the combat model. As a result, dependencies that are not in the combat model are incorporated. Hence, we can assess the strategic or cascading effects of destroying a set …

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