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HALF A LOAF. ARE NEW URBAN “HYBRIDS” A MARKETABLE OPTION?
Gary SANDS
Theoretical and Empirical Researches in Urban Management , 2009,
Abstract: New Urban developments offer a physical form that differs considerably from the dominant pattern of suburbanism in North America. While theorists argue that New Urbanist principles must be adopted in their entirety, property developers often find that compromises must be made to obtain necessary government approvals. This results in “hybrid” developments that lack all of the features of true New Urbanism. Based on surveys of residents of two Canadian communities, it would appear that some of the touchstones of New Urbanism are not actually essential and that there are few significant differences in in resident satisfaction levels between residents of different types of New Urban communities.
Cards, permutations, and sums
Bill Sands
Contributions to Discrete Mathematics , 2011,
Abstract: We are given four cards, each containing four nonnegative real numbers, written one below the other, so that the sum of the numbers on each card is 1. We are allowed to put the cards in any order we like, then we write down the first number from the first card, the second number from the second card, the third number from the third card, and the fourth number from the fourth card, and we add these four numbers together. We wish to find real intervals $[a,b]$ with the following property: there is always an ordering of the four cards so that the above sum lies in $[a,b]$. We prove that the intervals $[1,2]$ and $[2/3,5/3]$ are solutions to this problem. It follows that $$[0,1], [1/3,4/3], [2/3,5/3], [1,2]$$ are the only minimal intervals which are solutions. We also discuss a generalization to $n$ cards, and give an equivalent formulation of our results in matrix terms.
Thermodynamic Entropy And The Accessible States of Some Simple Systems
David Sands
Physics , 2007, DOI: 10.1088/0143-0807/29/1/013
Abstract: Comparison of the thermodynamic entropy with Boltzmann's principle shows that under conditions of constant volume the total number of arrangements in simple thermodynamic systems with temperature-independent heat capacities is TC/k. A physical interpretation of this function is given for three such systems; an ideal monatomic gas, an ideal gas of diatomic molecules with rotational motion, and a solid in the Dulong-Petit limit of high temperature. T1/2 emerges as a natural measure of the number of accessible states for a single particle in one dimension. Extension to N particles in three dimensions leads to TC/k as the total number of possible arrangements or microstates. The different microstates of the system are thus shown a posteriori to be equally probable, with probability T-C/k, which implies that for the purposes of counting states the particles of the gas are distinguishable. The most probable energy state of the system is determined by the degeneracy of the microstates.
Eliminating the Existential Threat from North Korea
Timothy Sands
- , 2018, DOI: 10.5923/j.scit.20180801.02
Abstract: The immergence of a belligerent North Korea threatening the United States with nuclear weapons is a new, shocking development that takes place in a paradigm that finds the U.S. in an outdated posture that stems largely from the laydown of its land-based nuclear forces. This research illustrates the vulnerability of the entire land-based nuclear force to a single North Korean nuclear ballistic missile launch via orbital dynamics and also rotational mechanics for attitude control to illustrate cross-track maneuverability producing a theorem that hypothesizes the new threat. This theorem is postulated, and then scientific analysis is provided as proof. With acceptance of this validated vulnerability, suggestions are offered to negate the vulnerability via the Base Realignment and Closure (BRAC) process. This process is required for any major realignment of U.S. force posture, so any defensive dispersal of land-based nuclear forces must rely upon the BRAC process to negate the new threat
Continuum of Learning: Combining Education, Training, and Experiences
Timothy Sands
- , 2018, DOI: 10.5923/j.edu.20180801.03
Abstract: The United States Air Force approved creation of a Force Development Commander and assigned this new role to the Commander, Air Education and Training Command. The force development commander will execute force development policy (established by the Deputy Chief of Staff for Personnel) and will provide agility, advocacy and accountability for the force development efforts. The force development commander is charged with executing and leading the strategic development of “total force” Airmen (i.e. airmen from Air National Guard, Air Force Reserves, Regular Air Force, and Civilian Service). This action will be accomplished through a deliberate process that combines education, training, and experiences, known as the Continuum of Learning, to produce the right expertise and competencies to meet the operational needs. The force development commander will lead, synchronize, and operationalize deliberate development through the Continuum of Learning as a comprehensive process by identifying, assessing, integrating, advocating, and tracking requirements and resources. In these ways the force development commander ensures appropriate focus on force development initiatives to address air force secretary and chief of staff
Battle-damage Tolerant Automatic Controls
Timothy Sands
- , 2018, DOI: 10.5923/j.eee.20180801.02
Abstract: The nature of adaptive controls, or controls for unpredictable systems, lends itself naturally to the concept of damage tolerant controls in high performing systems, such as aircraft and spacecraft. Recent technical demonstrations of damage tolerant aircraft prove the concept of adaptive controls in an operational environment. Research covered by this paper expands on the topic by discussing the application of adaptive controls to spacecraft and theory behind simulating damage tolerant control implementation. Simulation is then used to demonstrate the stability of adaptive controls when experiencing sudden mass loss and rapid changes in inertia
Autonomous Trajectory Generation for Deterministic Artificial Intelligence
Timothy Sands
- , 2018, DOI: 10.5923/j.eee.20180803.01
Abstract: Machine learning or statistical artificial intelligence examines averages in data to codify the best approach to make decisions based on the data, and the method notoriously requires large amounts of training data (statistically relevant amounts). On the other hand, data produced by systems that obey physical laws can use those laws as the deterministic structure for artificial intelligence, greatly reducing the requirement for large amounts of data to achieve high-precision performance. This article examines aspects of deterministic artificial intelligence comprised of self-awareness utilizing auto-trajectory generation followed by change-detection and identification, and then online learning. After the self-awareness algorithm is introduced, several auto-trajectory implementations are compared. Furthermore, learning methods are compared emphasizing recursive least squares and extended least squares learning compared to classical proportional-integral-derivate feedback implementations. Novel learning improvements realized 23.4% decreased mean error, and 34.0% decreased standard deviation compared to the standard recursive least squares optimal estimator error while max error decreased 33.0%. Four autonomous trajectory generation techniques were shown to produce accuracies form 10-4 to 10-9 with various computational burdens, providing a menu of implementation options
Developments in Angular Momentum Exchange
Timothy Sands
- , 2018, DOI: 10.5923/j.aerospace.20180601.01
Abstract: Under the assumption of indifferently statics stability attitude controller is designed for the warhead based on Lyapunov theory. And also, a pseudo-inverse steering law with null motions is used to generate the gimbal velocity commands for SGCMGs, according to the desired torque from the attitude controller. Comparing with the strategies with fins or thrusters, the ablation of the actuators can be prevented and the aerodynamic shape can be preserved in this one since SGCMGs are mounted inside the warhead directly. Comparing with the moving mass or flywheels, SGCMGs can output torque large enough to meet the need of large-scope attitude reorientation and stabilization for the warhead. Simulation results using a Pershing II ballistic missile with a certain warhead indicate that the control strategy with SGCMGs is feasible. This document provides a technical translation from Chinese to English of recent developments to improve the ability of the mobile penetration, Single Gimbal Control Moment Gyroscopes (SGCMG) are adopted instead of the control fins and vector thrusters to produce the torque for the attitude control of the re-entry warhead. In addition to the technical translation, the manuscript is set in the broader context of the literature
Space Mission Analysis and Design for Electromagnetic Suppression of Radar
Timothy Sands
- , 2018, DOI: 10.5923/j.ijea.20180801.01
Abstract: Inspired by aerial combat in the Balkans (Serbia and Kosovo) in 1999 with no known support suppressing enemy air defenses (SEAD) from space, this article proposes such by first introducing the reader to basic electromagnetic principles in order to evaluate the SEAD radar jamming mission from space. Next key design parameters are iterated in physics-based simulations to drive subsequent design efforts. Electromagnetic propagation equations are simulated and iterated to reveal key threshold values of key design parameters. It is revealed that only a single satellite is required for effective jamming with transmitter power of 2-9 kilowatts, transmission gain of at least 25 decibels, while maintaining a bandwidth less than 80 megahertz and assumed losses less than 30 decibels (where 10-20 decibels is typical). Using these key thresholds, space mission analysis and design (SMAD) is articulated in detail for the first time in the literature, revealing rough-order-of-magnitude budgets for system design. The design requires elements of mechanical engineering, electrical engineering, and aerospace/astronautical engineering at least. Astrodynamics reveals that a low-earth orbiting altitudes of 100-400 kilometers produces jamming effects on the target emitter for 4.8-10.2 minutes respectively producing jammer energy received by the targeted radar of -23.9 to -102.9 decibel-watts respectively. These key design features are used to establish a link-budget that reveals mission margin. Spacecraft key design budgets are calculated next revealing the requirement for a large spacecraft (~7333kg, 7.8m X 61.1m2) and large launch vehicle (Atlas V class). Budgets are also found for key satellite subsystems: payload, structures, thermal, power, TT&C, attitude control, and propellant. Reliability calculations and cost estimated are discussed, and normalized evaluation of jamming effectiveness is recommended. Lastly, key technology challenges of target acquisition, tracking, and spacecraft fine pointing are discussed, and current research efforts are highlighted inspiring future directions for technical innovations to enhance the design
Analysis of Determinisitic Aritificial Intelligence for Inertia Modifications and Orbital Disturbance
Timothy Sands
- , 2018, DOI: 10.5923/j.control.20180803.01
Abstract: Recent advances in the pioneering field of deterministic artificial intelligence applied to space systems energize this manuscripts evaluation of two novel aspects: sudden changes to moments of inertia (e.g. ejection or unplanned retention of an apogee kick motor), and disturbance rejection efficacy in the face of gravity gradient and atmospheric torques generated by density gradients. Encasing this research is critical evaluation of minimal error in attitude control in the face of these aspects. The errors are found to favourably compare to the capabilities demonstrated in the recent literature by deterministic artificial intelligence, and this key contribution allows researchers to conclude from this manuscript the strong efficacy in the face of retention of apogee kick motors, even in the presence of realistic orbital disturbances. Numerical modeling supports simulation experiments that also include requisite disciplines of space phoronomics and autonomous trajectory generation (proposed by companion manuscripts currently under peer review) yielding iterative analysis to establish efficacy. Some of the main findings include validation of the application of deterministic artificial intelligence techniques to attitude control in space in addition to elaboration of the coincident, fleeting effects of gravitation disturbances and atmospheric torques as a function of orbital altitude
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