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Air Force Institute of Technology

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Articles 3001 - 3030 of 5700

Full-Text Articles in Engineering

Determining The Surface-To-Air Missile Requirement For Western And Southern Part Of The Turkish Air Defense System, Omer Alkanat Mar 2008

Determining The Surface-To-Air Missile Requirement For Western And Southern Part Of The Turkish Air Defense System, Omer Alkanat

Theses and Dissertations

An air defense system is vital for countries to protect their homelands. Today, air defense systems consist of integrated systems such as early warning radars, fighter aircraft, airborne early warning aircraft and surface-to-air missile (SAM) systems. The Turkish air defense system does not have long range SAM systems. Turkey plans to procure SAM systems to protect her borders. This research develops two location optimization models to optimally locate SAM sites to defend specified areas of the nation. One of the models finds the minimum number of SAM sites to cover the specified area; the other finds the maximum coverage for …

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Robust Aircraft Squadron Scheduling In The Face Of Absenteeism, Osman Bahadir Gokcen Mar 2008

Robust Aircraft Squadron Scheduling In The Face Of Absenteeism, Osman Bahadir Gokcen

Theses and Dissertations

Air Force fighter aircraft squadrons the world over share a unique problem. Each requires complex training schedules coupling aircraft to pilots, the duo to missions and airspaces, and then the entire combination to a feasible time slot. Creating daily and weekly flight schedules that include shifts around the clock every day of the year with a set number of pilots is a time consuming job for manual schedulers within a squadron. Complicating matters is absenteeism. If one or more pilots are unable to perform their previously assigned tasks, due to sickness, aircraft failure, or reassignment, those tasks must be performed …

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Simulation Of National Intelligence Process With Fusion, Joseph S. Lupa Mar 2008

Simulation Of National Intelligence Process With Fusion, Joseph S. Lupa

Theses and Dissertations

This work is a follow on effort of two previous Master's theses. The first was Modeling and Simulation of the Military Intelligence Process by Captain Carl Pawling in 2004. The other was A Knowledge Matrix Modeling of the Intelligence Cycle by Captain Kevin Whaley in 2005. Both of these were done to facilitate the study and analysis of the intelligence process for the National Security Space Organization (NSSO). Here, modifications are made the Pawling model to include tasking multiple intelligence sources for data collection to fulfill Requests for Information (RFIs) and fusing the collected data into one new piece of …

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Forecasting Instability Indicators In The Horn Of Africa Region, Bryan R. Tannehill Mar 2008

Forecasting Instability Indicators In The Horn Of Africa Region, Bryan R. Tannehill

Theses and Dissertations

The forecasting of state failure and the associated indicators has been a topic of great interest to a number of different agencies. USAID, CENTCOM, the World Bank, the Center for Army Analyses, and others have all examined the subject based on their own specific objectives. Whether the goal is denying terrorists space in which to operate, deciding how to pre-position materials in anticipation of unrest, stabilizing foreign markets and trade, or preventing or mitigating humanitarian disasters, man made or otherwise, this topic has been of interest for over a decade. The Horn of Africa has been one of the least …

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An Analysis Of Methodologies & Best Practices For Rapidly Acquiring Technologies To Meet Urgent Warfighter Needs, Charles D. Solomon Mar 2008

An Analysis Of Methodologies & Best Practices For Rapidly Acquiring Technologies To Meet Urgent Warfighter Needs, Charles D. Solomon

Theses and Dissertations

The rapidly changing global security environment that today's military operates within requires an ever-increasing ability to quickly adapt to non-traditional threats. This has forced the United States to re-examine the traditional means of equipping its forces to ensure more agile acquisition practices are available to the Science and Technology (S&T) and acquisition communities. While there have been significant efforts to look towards industry for potential solutions to this problem, the heavily bureaucratic and restrictive government environment has made applying commercial lessons learned difficult. To effectively implement rapid fielding approaches within the government context, research into organizations facing the same or …

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Simulated Multi-Echelon Readiness-Based Inventory Leveling With Lateral Resupply, Todd C. Burnworth Mar 2008

Simulated Multi-Echelon Readiness-Based Inventory Leveling With Lateral Resupply, Todd C. Burnworth

Theses and Dissertations

For the past fifty years, U.S. Air Force reparable inventory has been allocated based on an analytic model developed by Dr. Craig C. Sherbrooke. Although versions of his model can be implemented easily with the help of a computer, the analytic approach fundamentally lacks the flexibility to address numerous logistics issues. This body of research will offer a novel alternative approach that will enable researchers to investigate currently unsolved logistics problems such as quantifying the benefits of lateral resupply.

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Discrete Event Simulation Of A Suppression Of Enemy Air Defenses (Sead) Mission, Ahmet Aydin Candir Mar 2008

Discrete Event Simulation Of A Suppression Of Enemy Air Defenses (Sead) Mission, Ahmet Aydin Candir

Theses and Dissertations

Contemporary military campaigns increasingly count on the use of air power. Suppression of enemy air defenses (SEAD) operations have been a crucial element of military air power for 50 years. Several developments and evolution in both air defense and attack systems suggest that SEAD missions will continue to have growing importance to air forces. Since SEAD operations have a significant impact on air campaigns, it is important to examine their efficiency and identify improvement opportunities. This study explores factors that influence SEAD operations through use of a discrete event simulation built in Arena and subsequent statistical analysis of the results.

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Combat Identification Modeling Using Robust Optimization Techniques, Taeho Kim Mar 2008

Combat Identification Modeling Using Robust Optimization Techniques, Taeho Kim

Theses and Dissertations

The purposes of this research were: (1) the modeling of a CID situation and (2) the search for robust and controllable input variable settings. The inputs were defined as controllable and noise variables and the confusion matrices in ROC theory were adapted to act as controllable factors. In this research a simple virtual battlespace representation is employed. The experimental results of the CID system are summarized by a posterior confusion matrix and throughout the confusion matrix analysis we can obtain all various types of data such as accuracy, error cost, error rates, and so forth. To find the optimal parameters …

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Robust Sensitivity Analysis Of Courses Of Action Using An Additive Value Model, Hunter A. Marks Mar 2008

Robust Sensitivity Analysis Of Courses Of Action Using An Additive Value Model, Hunter A. Marks

Theses and Dissertations

The Department of Defense (DoD) requires the ability to quantifiably measure progress in arenas that are complex and difficult to measure, such as the stability of a region. Therefore, the DoD works diligently to predict the effect of operations and sponsors research to improve prediction and analysis. They desire a repeatable, systematic methodology to aid in the selection of courses of action (COA) that efficiently meet stated objectives and quantitatively measure the degree of accomplishment of these objectives. The author proposes a value-focused thinking (VFT) decision analysis (DA) approach to this problem. This methodology not only aids in selection of …

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Simulation Modeling And Analysis Of F-16 Pilot Training Squadron, Adem Okal Mar 2008

Simulation Modeling And Analysis Of F-16 Pilot Training Squadron, Adem Okal

Theses and Dissertations

The need for fighter pilots in the Turkish Air Force is expected to increase with the planned acquisition of Joint Strike Fighters, ongoing new F-16 purchases, and other upgrades to the Turkish Air Force fighter inventory. This increased demand will affect the current fighter training squadron curriculum and scheduling. This study focuses on issues related to 143rd Oncel squadron F-16 Pilot Training with this projected increase in number of student pilots (SP). Completing the training periods on time is an important issue along with maintaining effective training performance. In our study the Total Time of the training period serves …

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Assessing Capabilities Of The High Energy Liquid Laser Area Defense System Through Combat Simulations, Ryan S. Ponack Mar 2008

Assessing Capabilities Of The High Energy Liquid Laser Area Defense System Through Combat Simulations, Ryan S. Ponack

Theses and Dissertations

High Energy Laser (HEL) technology continues to improve and its place in the battlefield is ever evolving. By combining the high energy delivery of solid state laser technology with the efficient thermal management of liquid laser technology, HELLADS has two main advantages over any HEL predecessors. One, the configuration is small and light enough to be carried on more tactical aircraft such as fighters. Two, the thermal management greatly increases HEL fire power by increasing dwell time on target. To assess HELLADS operational capabilities the test community has been challenged with how to effectively examine the advantages and limitations through …

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A Simulation Optimization Approach To The Design Of Unmanned Aircraft Systems, Emily C. Evans Mar 2008

A Simulation Optimization Approach To The Design Of Unmanned Aircraft Systems, Emily C. Evans

Theses and Dissertations

Military strategy and operations have evolved significantly over the past decade. This evolution has led to a change in the military resources required to carry out missions successfully. In line with these requirements, demand has increased for unmanned aerial vehicles (UAV) with enhanced capability to perform surveillance and to strike targets of interest. This research effort aids in the design of a next generation UAV by employing a simulation optimization approach. The goal of this research is to maximize the number of targets destroyed in a conflict scenario by a newly designed UAV that is subject to size, weight, and …

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A Decision Tool To Evaluate Budgeting Methodologies For Estimating Facility Recapitalization Requirements, Krista M. Hickman Mar 2008

A Decision Tool To Evaluate Budgeting Methodologies For Estimating Facility Recapitalization Requirements, Krista M. Hickman

Theses and Dissertations

The purpose of this research was to develop a decision tool to assist in the evaluation of facility recapitalization budget estimation models to determine which model was best suited for a particular organization. Specifically, this thesis sought to answer an overarching research question addressing the importance of recapitalization and the best method to estimate the facility recapitalization budget using the Department of Defense (DoD) as the subject of the research. A comprehensive literature review revealed ten existing recapitalization model alternatives to consider for implementation. The methodology used to develop a decision tool was based on the Value Focused Thinking (VFT) …

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The Impact Of Operations Tempo (Optempo) On Intentions To Depart The Military. Does The Increase Of Optempo Cause Action, Nathan P. Olsen Mar 2008

The Impact Of Operations Tempo (Optempo) On Intentions To Depart The Military. Does The Increase Of Optempo Cause Action, Nathan P. Olsen

Theses and Dissertations

Recent information in the field of Operations Tempo (OPTEMPO) has resulted in conflicting information on its effect on turnover intentions. This study evaluated the August 2004 Status of Forces Survey to determine if the sample demonstrated OPTEMPO had a curvilinear effect on turnover intentions when accounting for the moderators job satisfaction and organizational commitment while controlling for rank and gender. Linear regressions were used to determine if the relationship between OPTEMPO and turnover intentions were significant. When accounting for job satisfaction and organizational commitment the relationship between OPTEMPO and turnover intentions is not significant, this indicated that OPTEMPO and turnover …

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Linking Embeddedness And Macroinvertebrate In Two Southwest Ohio Streams, Jonathan P. Kochersberger Mar 2008

Linking Embeddedness And Macroinvertebrate In Two Southwest Ohio Streams, Jonathan P. Kochersberger

Theses and Dissertations

Environmental managers utilize a variety of tools when assessing lotic systems for stressors attributed to anthropogenic sources. Stream deposited sediment has been recognized as one of the major stressors affecting streams in the U.S. The detrimental effect on aquatic biota of sediment depositing within the interstitial spaces of stream substrate (embeddedness) has been established, yet lacking is an effective in situ method of quantifying embeddedness over short time periods. The goal of this research was to develop a short-term embeddedness (EMB) quantification method that can be linked to benthic macroinvertebrate health. Such a method would be a valuable tool when …

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Molecular Characterization Of Wetland Soil Bacterial Communities In Constructed Mesocosms, Elisabeth M. Leon Mar 2008

Molecular Characterization Of Wetland Soil Bacterial Communities In Constructed Mesocosms, Elisabeth M. Leon

Theses and Dissertations

16S rRNA gene analysis was performed on soil samples from a subsurface flow mesocosm experiment, mimicking a constructed wetland. Three typical wetland species of plant were used in nine of the columns and three columns were unplanted controls. Analyses showed that plant presence, plant species, and depth did not have a significant effect on microbial community composition. However, richness analyses illustrated that plant presence had a positive effect on richness, plant species analyses indicated that there was evidence that plant species affected richness in a significant manner, and lastly richness was negatively affected in the bottom depth for the control …

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Intelligence Surveillance And Reconnaissance Asset Assignment For Optimal Mission Effectiveness, Ryan D. Kappedal Mar 2008

Intelligence Surveillance And Reconnaissance Asset Assignment For Optimal Mission Effectiveness, Ryan D. Kappedal

Theses and Dissertations

This research develops mathematical programming techniques to solve an intelligence, surveillance, and reconnaissance sensor assignment problem for USSTRATCOM. The problem as specified is hypothesized to be difficult (i.e. np-hard). With the smallest test cases, the true optimal solution is found using simple optimization techniques, but, due to intractability, the optimal solutions for larger test cases are not found using these same techniques. Instead, heuristic techniques are applied to several test cases in order to determine the best, robust methodologies to find true or near optimal solutions. Specifically, simulated annealing (SA) is tested for convergence properties across several different parameter settings. …

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Risk-Based Comparison Of Classification Systems, Seth B. Wagenman Mar 2008

Risk-Based Comparison Of Classification Systems, Seth B. Wagenman

Theses and Dissertations

Performance measures for families of classification system families that rely upon the analysis of receiver operating characteristics (ROCs), such as area under the ROC curve (AUC), often fail to fully address the issue of risk, especially for classification systems involving more than two classes. For the general case, we denote matrices of class prevalences, costs, and class-conditional probabilities, and assume costs are subjectively fixed, acceptable estimates for expected values of class-conditional probabilities exist, and mutual independence between a variable in one such matrix and those of any other matrix. The ROC Risk Functional (RRF), valid for any finite number of …

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Velocity Estimate Following Air Data System Failure, Scott A. Mclaren Mar 2008

Velocity Estimate Following Air Data System Failure, Scott A. Mclaren

Theses and Dissertations

Modern high performance aircraft can provide amazing performance due in part to their advanced flight control systems that require gain scheduling to provide optimum performance over a huge flight envelope. In modern fighter aircraft, this gain scheduling is a function of airspeed, and almost all of the research involving aircraft gain scheduling assumes aircraft airspeed to be a known quantity. The purpose of this research was to investigate a method of determining an aircraft’s airspeed in the event of total air data system failure. The process began by combining known aircraft information following an air data system failure to determine …

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Handling Qualities Evaluation Of A Supersonic Tailless Air Vehicle, Steven W. Speares Mar 2008

Handling Qualities Evaluation Of A Supersonic Tailless Air Vehicle, Steven W. Speares

Theses and Dissertations

This thesis presents the results of a handling qualities evaluation of a supersonic tailless air vehicle. The 2006 Quadrennial Defense Review mandated the need for the next generation of long-range strike aircraft by 2018. Due to speed and stealth requirements, this resulted in a tailless aircraft with an instantaneous center of rotation located well forward of that of a conventional aircraft. This thesis examines how this center of rotation affected pilot handling qualities ratings. This effect should have been the most pronounced during approach and landing, and was where the testing focused. The goal of this research was to develop …

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Design Of An Oxygen Turbopump For A Dual Expander Cycle Rocket Engine, William S. Strain Mar 2008

Design Of An Oxygen Turbopump For A Dual Expander Cycle Rocket Engine, William S. Strain

Theses and Dissertations

The design of a pump intended for use with a dual expander cycle (LOX/H2) engine is presented. This arrangement offers a number of advantages over hydrogen expander cycles; among these are the elimination of gearboxes and inter-propellant purges and seals, an extended throttling range, and higher engine operating pressures and performance. The target engine has been designed to meet the needs of Phase III of the Integrated High Payoff Rocket Propulsion Technology (IHPRPT) program; thus, this pump must meet the program’s reliability, maintainability, and service life goals. In addition, this pump will be driven by warm gaseous oxygen. …

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Real-Time Navigation And Flight Path Generation For Tracking Stop-And-Go Targets With Miniature Air Vehicles, Nate A. Terning Mar 2008

Real-Time Navigation And Flight Path Generation For Tracking Stop-And-Go Targets With Miniature Air Vehicles, Nate A. Terning

Theses and Dissertations

This research effort focuses on using a heuristic approach to determine the optimal flight path required to put an Unmanned Aircraft System’s (UAS) sensor on a moving target in the presence of a constant wind field. This thesis builds on past work using dynamic optimization techniques to calculate minimum time to target. The computationally intensive dynamic optimization routines in their current form take a prohibitive amount of time to calculate and ultimately result in erroneous flight path predictions due to inherent execution time latencies. Therefore an iterative, suboptimal heuristic approach was explored to mitigate excessive calculation times and ultimately yield …

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Investigation Into Fretting Fatigue Under Cyclic Contact Load And In Conjuction With Fatigue Of Titanium Alloy, Abdulla A. Al-Noaimi Mar 2008

Investigation Into Fretting Fatigue Under Cyclic Contact Load And In Conjuction With Fatigue Of Titanium Alloy, Abdulla A. Al-Noaimi

Theses and Dissertations

Fretting fatigue is the surface damage that occurs at the interface between two components that are undergoing a small amplitude oscillatory movements. It results in a reduction of the material life comparing to the plain fatigue. Most of the previous works were accomplished under a constant applied contact load and a little effort has been done under a variable contact load, while none of these studies have taken the phase difference between the axial and the contact load. The primary goal of this study is to investigate the effect of phase difference between axial and contact loads on fretting fatigue …

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Space Based Satellite Tracking And Characterization Utilizing Non-Imaging Passive Sensors, Bradley R. Townsend Mar 2008

Space Based Satellite Tracking And Characterization Utilizing Non-Imaging Passive Sensors, Bradley R. Townsend

Theses and Dissertations

A technique is developed to determine the orbit of a sunlight illuminated satellite passing through the field-of-view of a sensor platform in a Highly Elliptical Orbit (HEO) and Geosynchronous orbit (GEO). The technique develops two different methods of initial orbit determination. The first relies on the Gauss initial orbit determination method to develop an estimate of the state from angular data. The second method relies on positional data of the target relative to the Earth’s background to determine an estimate of the state. These estimates are then refined in a non-linear least squares routine. This estimate of the state is …

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Network Visualization Design Using Prefuse Visualization Framework, John Mark Belue Mar 2008

Network Visualization Design Using Prefuse Visualization Framework, John Mark Belue

Theses and Dissertations

Visualization of network simulation events or network visualization is an effective and low cost method to evaluate the health and status of a network and analyze network designs, protocols, and network algorithms. This research designed and developed a network event visualization framework using an open source general visualization toolkit. This research achieved three major milestones during the development of this framework: A robust network simulator trace file parser, multiple network visualization layouts {including user-defined layouts, and precise visualization timing controls and integrated display of network statistics. The parser architecture is extensible to allow customization of simulator trace formats that are …

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Digital Fingerprinting Of Field Programmable Gate Arrays, James W. Crouch Mar 2008

Digital Fingerprinting Of Field Programmable Gate Arrays, James W. Crouch

Theses and Dissertations

Commercial off-the-shelf (COTS) component usage is becoming more prevalent in military applications due to current Department of Defense (DoD) policies. The easy accessibility of COTS will give reverse engineers a higher probability of successfully tampering, coping, or reverse engineering circuits that contain critical capabilities. To prevent this and verify the trustworthiness of hardware, circuit identification tags or serials numbers can be used. However, these values can be easily obtained and forged. To protect critical DoD technologies from possible exploitation, there is an urgent need for a reliable method to confirm a circuit’s identity using a set of unique unforgettable metrics. …

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Signal Processing Design Of Low Probability Of Intercept Waveforms, Nathaniel C. Liefer Mar 2008

Signal Processing Design Of Low Probability Of Intercept Waveforms, Nathaniel C. Liefer

Theses and Dissertations

This thesis investigates a modification to Differential Phase Shift Keyed (DPSK) modulation to create a Low Probability of Interception/Exploitation (LPI/LPE) communications signal. A pseudorandom timing offset is applied to each symbol in the communications stream to intentionally create intersymbol interference (ISI) that hinders accurate symbol estimation and bit sequence recovery by a non-cooperative receiver. Two cooperative receiver strategies are proposed to mitigate the ISI due to symbol timing offset: a modified minimum Mean Square Error (MMSE) equalization algorithm and a multiplexed bank of equalizer filters determined by an adaptive Least Mean Square (LMS) algorithm. Both cooperative receivers require some knowledge …

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Development And Flight Of A Robust Optical-Inertial Navigation System Using Low-Cost Sensors, Michael B. Nielsen Mar 2008

Development And Flight Of A Robust Optical-Inertial Navigation System Using Low-Cost Sensors, Michael B. Nielsen

Theses and Dissertations

This research develops and tests a precision navigation algorithm fusing optical and inertial measurements of unknown objects at unknown locations. It provides an alternative to the Global Positioning System (GPS) as a precision navigation source, enabling passive and low-cost navigation in situations where GPS is denied/unavailable. This paper describes two new contributions. First, a rigorous study of the fundamental nature of optical/inertial navigation is accomplished by examining the observability grammian of the underlying measurement equations. This analysis yields a set of design principles guiding the development of optical/inertial navigation algorithms. The second contribution of this research is the development and …

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Hyperspectral-Augmented Target Tracking, Neil A. Soliman Mar 2008

Hyperspectral-Augmented Target Tracking, Neil A. Soliman

Theses and Dissertations

With the global war on terrorism, the nature of military warfare has changed significantly. The United States Air Force is at the forefront of research and development in the field of intelligence, surveillance, and reconnaissance that provides American forces on the ground and in the air with the capability to seek, monitor, and destroy mobile terrorist targets in hostile territory. One such capability recognizes and persistently tracks multiple moving vehicles in complex, highly ambiguous urban environments. The thesis investigates the feasibility of augmenting a multiple-target tracking system with hyperspectral imagery. The research effort evaluates hyperspectral data classification using fuzzy c-means …

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Scripted Mobile Network Routing In A Contested Environment, Anthony R. Otto Mar 2008

Scripted Mobile Network Routing In A Contested Environment, Anthony R. Otto

Theses and Dissertations

Mobile wireless network protocols currently run on optimistic routing algorithms, adjusting node connectivity only when the chosen connectivity metrics, such as signal strength, pass beyond minimum thresholds. Optimistic routing has several weaknesses. Optimistic routing suffers from increased network overhead during increased frequency of node movement and increased node density per area, and optimistic routing also suffers from non-optimistic access change for individual nodes. The overall communication throughput of a network may be increased if the network topology change is scripted; a scripted plan can allow messages to travel along a more efficient topological path while creating less topology control traffic. …

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