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2001

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Solving The Protein Structure Prediction Problem With Fast Messy Genetic Algorithms (Scaling The Fast Messy Genetic Algorithm To Medium-Sized Peptides By Detecting Secondary Structures), Steven R. Michaud Mar 2001

Solving The Protein Structure Prediction Problem With Fast Messy Genetic Algorithms (Scaling The Fast Messy Genetic Algorithm To Medium-Sized Peptides By Detecting Secondary Structures), Steven R. Michaud

Theses and Dissertations

The ability to accurately predict a polypeptide's molecular structure given its amino acid sequence is important to numerous scientific, medical, and engineering applications. Studies have been conducted in the application of Genetic Algorithms (GAs) to this problem with promising initial results. In this thesis report, we use the fast messy Genetic Algorithm (fmGA) to attempt to find the minimization of an empirical CHARMM energy model and generation of the associated conformation. Previous work has shown that the fmGA provided favorable results, at least when applied to the pentapeptide Met-Enkephalin. We extend these results to a larger Polyalinine peptide by utilizing …

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Software Domain Model Integration Methodology For Formal Specifications, Joel C. Nonnweiler Mar 2001

Software Domain Model Integration Methodology For Formal Specifications, Joel C. Nonnweiler

Theses and Dissertations

Using formal methods to create automatic code generation systems is one of the goals of Knowledge Based Software Engineering (KBSE) groups. The research of the Air Force Institute of Technology KBSE group has focused on the utilization of formal languages to represent domain model knowledge within this process. The code generation process centers around correctness preserving transformations that convert domain models from their analysis representations through design to the resulting implementation code. The diversity of the software systems that can be developed in this manner is limited only by the availability of suitable domain models. Therefore it should be possible …

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Air Vehicle Optimal Trajectories For Radar Exposure Minimization, Michael C. Novy Mar 2001

Air Vehicle Optimal Trajectories For Radar Exposure Minimization, Michael C. Novy

Theses and Dissertations

This study addresses the problem of analyzing the single vehicle path planning problem for radar exposure minimization. The calculus of Variations and optimal control are applied to formulate the cost function and numerical algorithms are used to solve for the optimal paths. Cost sensitivity to path length is analyzed for flight against one radar; a second radar is then included in the formulation and the optimal path for flight between the radars is found for cases of equal and unequal radar power. The costs of the optimal path, direct path, and Voronoi diagram-generated paths are compared. Results indicate low sensitivity …

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Forecasting Readiness: Using Regression To Predict The Mission Capability Of Air Force F-16 Fighter Aircraft, Steven A. Oliver Mar 2001

Forecasting Readiness: Using Regression To Predict The Mission Capability Of Air Force F-16 Fighter Aircraft, Steven A. Oliver

Theses and Dissertations

According to many, the readiness of America's forces deteriorated in the 1990s. In the Air Force, the combat readiness of its fighter aircraft has declined. One of its indicators of combat readiness, the mission capable rate, is used to identify the percentage of aircraft unable to perform their missions. From FY94-FY98, the aggregate total not mission capable rate for maintenance steadily increased from 14% to 18.2% while total not mission capable rate for supply increased from 5.5% to 17.5% between FY86 and FY00. The USAF uses the funding/Availability Multi-Method Allocator for Spares model to forecast these rates for its aircraft. …

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Selecting A Software Engineering Methodology Using Multiobjective Decision Analysis, Scott A. O'Malley Mar 2001

Selecting A Software Engineering Methodology Using Multiobjective Decision Analysis, Scott A. O'Malley

Theses and Dissertations

With the emergence of agent-oriented software engineering methodologies, software developers have a new set of tools to solve complex software requirements. One problem software developers face is to determine which methodology is the best approach to take to developing a solution. A number of factors go into the decision process. This thesis defines a decision making process that can be used by a software engineer to determine whether or not a software engineering approach is an appropriate system development strategy. This decision analysis process allows the software engineer to classify and evaluate a set of methodologies while specifically considering the …

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Information Security: Securing Smart Cards With Iris Recognition, Orval E. Phelps Mar 2001

Information Security: Securing Smart Cards With Iris Recognition, Orval E. Phelps

Theses and Dissertations

This thesis examines the application of iris recognition technology to the problem of keeping smart cards secure. In order to understand the technology, a comprehensive literature review was conducted. The biological components of the iris were examined to ensure that they were truly random in development and static through the lifetime of the individual. Specifically, the physical structure of what comprises the iris was examined in detail. The data gathered indicates that the iris is formed early in development, random in structure, and stable throughout the person's lifetime. Next, the iris recognition process and resulting recognition code was examined to …

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Using A Distributed Object-Oriented Database Management System In Support Of A High-Speed Network Intrusion Detection System Data Repository, Phillip W. Polk Mar 2001

Using A Distributed Object-Oriented Database Management System In Support Of A High-Speed Network Intrusion Detection System Data Repository, Phillip W. Polk

Theses and Dissertations

The Air Force has multiple initiatives to develop data repositories for high-speed network intrusion detection systems (IDS). All of the developed systems utilize a relational database management system (RDBMS) as the primary data storage mechanism. The purpose of this thesis is to replace the RDBMS in one such system developed by AFRL, the Automated Intrusion Detection Environment (AIDE), with a distributed object-oriented database management system (DOODBMS) and observe a number of areas: its performance against the RDBMS in terms of IDS event insertion and retrieval, the distributed aspects of the new system, and the resulting object-oriented architecture. The resulting system, …

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A Model To Predict Diffraction Attenuation Resulting From Signal Propagation Over Terrain In Low Earth Orbit Satellite Systems, Peter R. Pollock Mar 2001

A Model To Predict Diffraction Attenuation Resulting From Signal Propagation Over Terrain In Low Earth Orbit Satellite Systems, Peter R. Pollock

Theses and Dissertations

This study focused on multipath communication propagation impairments to the LEOSAT communications channel. Two terrain diffraction models, based on the geometric theory of diffraction (GTD), were developed and applied to the space-to-ground communications channel. These models were used to predict the impact of terrain on the performance of three LEOSAT communication systems with designs based on the Iridium, Globalstar and Orbcomm implementations. The study verified the feasibility of applying models based on the GTD rather than empirical or statistical models, to approximate the effect of propagating signals over terrain. Both models confirm that signal blockage and multipath propagation, due to …

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Revising R & D Program Budgets When Considering Funding Curtailment With A Weibull Model, Paul H. Porter Mar 2001

Revising R & D Program Budgets When Considering Funding Curtailment With A Weibull Model, Paul H. Porter

Theses and Dissertations

This research develops an analytical technique to estimate the impact of funding curtailment on an R&D program. The method quickly produces a revised budget by year for an on-going R&D program when funding in one year is reduced. We assume program requirements remain unchanged. The program duration may be unchanged or "stretched" to a later completion date. We use the Rayleigh and Weibull functions to model expenditure profiles, which forms basis of the analytical approach. Our proposed methodology accounts for budget outlay rates and inflation. We validate the proposed analytical technique using historical cost data from several programs.

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Determining The Value Of Groundwater Contamination Source Removal: A Methodology, Benjamin C. Recker Mar 2001

Determining The Value Of Groundwater Contamination Source Removal: A Methodology, Benjamin C. Recker

Theses and Dissertations

Subsurface contamination by industrial chemicals is one of the most prevalent and costly environmental problems facing the United States government. This contamination problem must be managed to protect human health and the environment. Two basic strategies are used to deal with subsurface contamination: source removal and contaminant containment. While much cost and performance data are available for individual technologies associated with each of these strategies, there have been very few studies that have examined the benefits of implementing source removal technologies in order to reduce contaminant containment (and hopefully total) costs. This study examines the tradeoff between extent of source …

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Modeling Chlorinated Ethene Removal In The Methanogenic Zone Of Constructed Wetlands: A System Dynamics Approach, Randall L. Roberts Mar 2001

Modeling Chlorinated Ethene Removal In The Methanogenic Zone Of Constructed Wetlands: A System Dynamics Approach, Randall L. Roberts

Theses and Dissertations

The purpose of this study is to gain understanding of the dynamics of the processes that degrade Perchloroethene (PCE) to ethene, within the confines of the methanogenic zone of a constructed wetland. A system dynamics modeling approach is used. This model is focused on determining conditions that will enhance contaminant degradation. The chemical and biological processes within the methanogenic zone of a wetland system are extremely complex and dynamic processes. The model is broken up into three simultaneous processes: dechlorination, methanogenesis, and fermentation. The system behavior of the methanogenic zone can be adequately described by the classical formulations of representative …

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Knowledge Management In The Cost Analysis Knowledge Domain: Generating, Organizing, And Developing Knowledge For Crosschecking Cost Estimates, Ryan J. Rueve Mar 2001

Knowledge Management In The Cost Analysis Knowledge Domain: Generating, Organizing, And Developing Knowledge For Crosschecking Cost Estimates, Ryan J. Rueve

Theses and Dissertations

Two problems the Aeronautical Systems Center's Acquisition Cost Division (ASC/FMC) is encountering with its Life Cycle Cost/Lean Process Initiative (LCC/LPI) efforts are (Marshall and Seibel. 2000): (1) a high proportion of inexperienced to experienced cost analysts which makes access to valuable expertise limited, and (2) knowledge loss due to turnover of experienced cost analysts. To address these problems, this thesis presents a four-step tailored methodology to identity tasks or processes important to the functioning of an organization, capture knowledge from experts pertaining to those tasks (generate content), convert that knowledge into a flowchart (organize content), and have experts critique the …

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Phugoid Damping Control, Nicolas J. Schindeler Mar 2001

Phugoid Damping Control, Nicolas J. Schindeler

Theses and Dissertations

A novel phugoid damping control design methodology is developed, based on the use of wind axes and a point-mass aircraft model. The state variables are air speed, flight path angle, and heading angle, the control variables are thrust setting, angle of attack, bank angle, and sideslip angle, and the command signals are airspeed, flight path angle, and heading angle or heading rate. All the variables and parameters are nondimensionalized. A multivariable set point controller is developed which consists of: (1) a trim calculation-based nonlinear feed-forward control computer; thus, given a commanded new trim state (air speed, flight path angle, and …

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Analysis Of Cloud-To-Ground Lightning Clusters With Radar Composite Imagery, Rhonda B. Scott Mar 2001

Analysis Of Cloud-To-Ground Lightning Clusters With Radar Composite Imagery, Rhonda B. Scott

Theses and Dissertations

The most recent research conducted at the Air Force Institute of Technology involved studying a large volume of lightning data without coupling radar imagery (Parsons 2000). Parsons finding could not be acted on because no individual storms were studied. The primary goal of this research is to determine whether the techniques used by Parsons can be applied to storms by examining the radar imagery and lightning data. This research used the methodology applied to lightning data by Parsons and radar imagery to determine whether the location of lightning clusters were located near storms. A composite reflectivity radar image was generated …

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Effects On The Red-Cockaded Woodpecker From Various Spatial And Temporal Applications Of Management Practices, Chad F. Schroeder Mar 2001

Effects On The Red-Cockaded Woodpecker From Various Spatial And Temporal Applications Of Management Practices, Chad F. Schroeder

Theses and Dissertations

The Red-Cockaded Woodpecker (RCW) is an endangered species endemic to southeastern pine forests in the United States. RCWs are cooperative breeding birds that live together in clusters of old-growth pine trees in which they construct their nesting cavities. The cavities are constructed in living pines, which are predominantly longleaf pines. RCWs also forage upon older pines, preferably longleaf pine. The Endangered Species Act, along with other DoD regulations, requires DoD installations to protect the RCWs and restore their habitat. A popular management practice converts off-site (non-native) pines back to a region's indigenous pines. Conversion provides the best long term RCW …

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Traveling Salesman Problem For Surveillance Mission Using Particle Swarm Optimization, Barry R. Secrest Mar 2001

Traveling Salesman Problem For Surveillance Mission Using Particle Swarm Optimization, Barry R. Secrest

Theses and Dissertations

The surveillance mission requires aircraft to fly from a starting point through defended terrain to targets and return to a safe destination (usually the starting point). The process of selecting such a flight path is known as the Mission Route Planning (MRP) Problem and is a three-dimensional, multi-criteria (fuel expenditure, time required, risk taken, priority targeting, goals met, etc.) path search. Planning 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 …

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Crossing Myriad Borders: A Dimensional Analysis Of The Migration And Health Experiences Of Indigenous Oaxacan Women, Sharon Mcguire Phd, Op, Msn, Rn-C Mar 2001

Crossing Myriad Borders: A Dimensional Analysis Of The Migration And Health Experiences Of Indigenous Oaxacan Women, Sharon Mcguire Phd, Op, Msn, Rn-C

Dissertations

The growing feminization of the migration of ethnic indigenous women, such as Mixtecs, Zapotecs and Triquis from the southern Mexican state of Oaxaca, are altering the dynamics and configuration of traditional Mexican migration, making it especially significant for the health professions. Informed by a postcolonial ecofeminist paradigm, this bi-national grounded theory study explored the migration and health experiences of indigenous Oaxacan immigrant/migrant women. Data collection using participant observation and interviewing occurred in Oaxaca, Mexico, along the US-Mexico border, and the interior of California. Dimensional analysis was used as the method of data analysis to generate theoretical understandings of these phenomena. …

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An Examination Of Student Achievement In Michigan Charter Schools, Randall W. Eberts, Kevin Hollenbeck Mar 2001

An Examination Of Student Achievement In Michigan Charter Schools, Randall W. Eberts, Kevin Hollenbeck

Upjohn Institute Working Papers

Since their inception in 1991, the number of and the student enrollment in charter school have burgeoned. However, little attention has been paid to their effects on student achievement. Proponents hypothesize direct and indirect positive impacts of charter schools on student achievement. The direct effect is through the restructuring of teaching and learning processes. The indirect effect operates through peer effects on learning and through the market forces of competition. This paper focuses on student achievement in charter schools in Michigan. The analyses presented here suggest that students attending charter schools in Michigan are not reaching the same levels of …

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0920+3517_Nir_Spex, Maria Teresa Ruiz Mar 2001

0920+3517_Nir_Spex, Maria Teresa Ruiz

Publications and Research

No abstract provided.

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Mapping Weekly Rangeland Vegetation Productivity Using Modis Algorithms, Matthew Clark Reeves, Jerome C. Winslow, Steven W. Running Mar 2001

Mapping Weekly Rangeland Vegetation Productivity Using Modis Algorithms, Matthew Clark Reeves, Jerome C. Winslow, Steven W. Running

Numerical Terradynamic Simulation Group Publications

The great spatial extent of rangelands combined with recent emphasis on rangeland health has prompted a need for more efficient and cost effective management tools. The Moderate Resolution Imaging Spectroradiometer (MODIS) sensor of the Earth Observing System (EOS) will offer improved and more timely monitoring of rangeland vegetation, and, unlike any previous satellite sensor, the publicly available MODIS data stream will include estimates of rangeland productivity. These estimations of rangeland productivity can be used regionally for measuring biomass production and will be available every eight-days, with global coverage at 1- km^ resolution. MODIS derived estimates of rangeland productivity combine remote …

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Amazon.Com: A Look At Patenting Computer Implemented Business Methods Following State Street, James E. Landis Mar 2001

Amazon.Com: A Look At Patenting Computer Implemented Business Methods Following State Street, James E. Landis

North Carolina Journal of Law & Technology

No abstract provided.

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Helping Elementary Education Majors Brush Up On Mathematical Modeling: Insights From A Field Test Of A New Online Learning Prototype, Neal Grandgenett, Arthur I. Zygielbaum, Elliott Ostler, Steve Hamersky, Bob Pawloski Mar 2001

Helping Elementary Education Majors Brush Up On Mathematical Modeling: Insights From A Field Test Of A New Online Learning Prototype, Neal Grandgenett, Arthur I. Zygielbaum, Elliott Ostler, Steve Hamersky, Bob Pawloski

Teacher Education Faculty Proceedings & Presentations

This paper describes insights related to the potential use of on-line training modules with elementary education pre-service teachers for enhancing their experience and background in mathematical modeling. These insights resulted from a field test of a new online learning prototype developed within a National Science Foundation Proof-of-Concept project. The insights listed in the paper are further supported by two URL addresses that link to detailed notes, background documents, and various demonstration pieces.

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Crime Rates And Confidence In The Police: America's Changing Attitudes Toward Crime And Police, 1972-1999, Georgia Ackerman, Bobbie Anderson, Scott Jensen, Randy Ludwig, Darrel Montero, Nicole Plante, Vince Yanez Mar 2001

Crime Rates And Confidence In The Police: America's Changing Attitudes Toward Crime And Police, 1972-1999, Georgia Ackerman, Bobbie Anderson, Scott Jensen, Randy Ludwig, Darrel Montero, Nicole Plante, Vince Yanez

The Journal of Sociology & Social Welfare

This paper examines American national public opinion on crime and the American police force. The data were gathered from published opinion polls of national samples of adults taken from 1972-1999. The findings reveal that Americans have contradictory perceptions regarding crime in their area, crime in our nation, confidence in the police, and the honesty of the nation's police officers. A growing number of respondents report that crime seems to be decreasing; however, a majority of Americans still report that there is more crime in their area than there was a year ago. These are only a few examples of the …

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Infosphere Project: An Overview, Calton Pu, Jonathan Walpole Mar 2001

Infosphere Project: An Overview, Calton Pu, Jonathan Walpole

Computer Science Faculty Publications and Presentations

We describe the Infosphere project, which is building the systems software support for information-driven applications such as digital libraries and electronic commerce. The main technical contribution is the Infopipe abstraction to support information flow with quality of service. Using building blocks such as program specialization, software feedback, domain-specific languages, and personalized information filtering, the Infopipe software generates code and manage resources to provide the specified quality of service with support for composition and restructuring.

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Bistable Operation Of A Two-Section 1.3-Mm Inas Quantum Dot Laser—Absorption Saturation And The Quantum Confined Stark Effect, Xiaodong Huang, A. Stintz, Hua Li, Audra Rice, G. T. Liu, L.F. Lester, Julian Cheng, K.J. Malloy Mar 2001

Bistable Operation Of A Two-Section 1.3-Mm Inas Quantum Dot Laser—Absorption Saturation And The Quantum Confined Stark Effect, Xiaodong Huang, A. Stintz, Hua Li, Audra Rice, G. T. Liu, L.F. Lester, Julian Cheng, K.J. Malloy

Faculty Publications

Room temperature, continuous-wave bistability was observed in oxide-confined, two-section, 1.3- m quantum-dot (QD) lasers with an integrated intracavity quantum-dot saturable absorber. The origin of the hysteresis and bistability were shown to be due to the nonlinear saturation of the QD absorption and the electroabsorption induced by the quantum confined Stark effect.

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Modeling The Transient Rate Behavior Of Bandwidth Sharing As A Hybrid Control System, Kang Li, Molly H. Shor, Jonathan Walpole, Calton Pu Mar 2001

Modeling The Transient Rate Behavior Of Bandwidth Sharing As A Hybrid Control System, Kang Li, Molly H. Shor, Jonathan Walpole, Calton Pu

Computer Science Faculty Publications and Presentations

This paper uses hybrid control to model a problem of computer network systems, the dynamic behavior of bandwidth sharing among competing TCP traffic. It has been well known in the computer network community that well-behaved (TCP-friendly) congestion control mechanisms are crucial to the robustness of the Internet. Congestion control determines the transmission rate for each flow. Right now, most TCP-friendly research focuses only on the average throughput behavior without considering how the data is sent out in the short-term (e.g. bursty or smooth). However, recent experimental results show that short-term rate adjustments can change the bandwidth sharing result. Therefore, it …

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Moving Towards Massively Scalable Video-Based Sensor Networks, Wu-Chi Feng, Jonathan Walpole, Calton Pu, Wu-Chang Feng Mar 2001

Moving Towards Massively Scalable Video-Based Sensor Networks, Wu-Chi Feng, Jonathan Walpole, Calton Pu, Wu-Chang Feng

Computer Science Faculty Publications and Presentations

Networking and computing technologies are becoming advanced enough to enable a wealth of diverse applications that will drastically change our everyday lives. Some past examples of these developments include the World Wide Web and wireless data networking infrastructures. As is quite obvious, the World Wide Web has enabled a fundamental change in the way many people deal with day-to-day tasks. Through the web, one can now make on-line reservations for travel, pay bills through on-line banking services, and view personalized on-line newscasts. More recently, developments in wireless technologies have enabled anywhere, anytime access to information over wireless medium. As wireless …

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Report, Economic Contributions Of Baptist Health Systems Of South Florida, March 2001, Usf Center For Economic Development Research Mar 2001

Report, Economic Contributions Of Baptist Health Systems Of South Florida, March 2001, Usf Center For Economic Development Research

Center for Economic Development Research (CEDR) Collection

This analysis quantifies the Baptist Health Systems of South Florida's economic contribution to the Miami-Dade County and Monroe County regions, focusing on operating expenditures, payroll, and major capital investment expenditures.

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The Past Is Prologue: American Catholic Education And The New Century, Timothy Walch Mar 2001

The Past Is Prologue: American Catholic Education And The New Century, Timothy Walch

Journal of Catholic Education

The author of a recent history of American Catholic education points to three ongoing traditions”tenacity, adaptability, and identity”as evidence that parochial education will continue well into the next century. In this personal essay, Walch challenges pessimistic assessment of Catholic education that appeared in Phi Delta Kappan. He also highlights other, more positive assessments of Catholic schooling. Walch concludes that even though American Catholic parochial education will never again attain the position of influence it had in the mid-20th century, parish schools will remain important education laboratories for the coming century.

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Why Are There Warriors In Plato's Republic?, John Patrick Coby Mar 2001

Why Are There Warriors In Plato's Republic?, John Patrick Coby

Government: Faculty Publications

The warriors are a troublesome addition to the city founded by Socrates. Continuous supervision and a heavy-handed pedagogy are required just to keep them from oppressing the producing class. They also never accomplish the mission they initially are given — the violent taking of adjacent lands. So why are they summoned and set up in power? For that matter, why is spiritedness cultivated instead of discouraged or suppressed? The above questions indicate that there is a case to be made against warriors in the city and spiritedness in the soul. After making that case, the paper turns to constructing a …

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