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Theses/Dissertations

2009

Air Force Institute of Technology

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Articles 1 - 29 of 29

Full-Text Articles in Computer Engineering

Tailored Systems Architecture For Design Of Space Science And Technology Missions Using Dodaf V2.0, Nicholas J. Merski Dec 2009

Tailored Systems Architecture For Design Of Space Science And Technology Missions Using Dodaf V2.0, Nicholas J. Merski

Theses and Dissertations

The use of systems architecture, following a set of integrated descriptions from an architecture framework, has been well codified in Department of Defense acquisition and systems engineering. However, in the Space Science and Technology (S&T) community, this guidance and practice is not commonly adopted. This paper outlines an approach to leverage the changes made in DoD Architecture Framework 2.0 (DoDAF2.0), and the renewed emphasis on data and support to acquisition decision analysis. After decomposing the Space S&T design lifecycle into phases, design milestones and activities using process models, a set of DoDAF prescribed and Fit-for-Purpose views are constructed into a …

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Performance Analysis Of Live-Virtual-Constructive And Distributed Virtual Simulations: Defining Requirements In Terms Of Temporal Consistency, Douglas D. Hodson Dec 2009

Performance Analysis Of Live-Virtual-Constructive And Distributed Virtual Simulations: Defining Requirements In Terms Of Temporal Consistency, Douglas D. Hodson

Theses and Dissertations

This research extends the knowledge of live-virtual-constructive (LVC) and distributed virtual simulations (DVS) through a detailed analysis and characterization of their underlying computing architecture. LVCs are characterized as a set of asynchronous simulation applications each serving as both producers and consumers of shared state data. In terms of data aging characteristics, LVCs are found to be first-order linear systems. System performance is quantified via two opposing factors; the consistency of the distributed state space, and the response time or interaction quality of the autonomous simulation applications. A framework is developed that defines temporal data consistency requirements such that the objectives …

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A Physical Model Of Human Skin And Its Application For Search And Rescue, Abel S. Nunez Dec 2009

A Physical Model Of Human Skin And Its Application For Search And Rescue, Abel S. Nunez

Theses and Dissertations

For this research we created a human skin reflectance model in the VIS and NIR. We then modeled sensor output for an RGB sensor based on output from the skin reflectance model. The model was also used to create a skin detection algorithm and a skin pigmentation level (skin reflectance at 685nm) estimation algorithm. The average root mean square error across the VIS and NIR between the skin reflectance model and measured data was 2%. The skin reflectance model then allowed us to generate qualitatively accurate responses for an RGB sensor for different biological and lighting conditions. To test the …

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Electronic Image Stabilization For Mobile Robotic Vision Systems, Michael John Smith Sep 2009

Electronic Image Stabilization For Mobile Robotic Vision Systems, Michael John Smith

Theses and Dissertations

When a camera is affixed on a dynamic mobile robot, image stabilization is the first step towards more complex analysis on the video feed. This thesis presents a novel electronic image stabilization (EIS) algorithm for small inexpensive highly dynamic mobile robotic platforms with onboard camera systems. The algorithm combines optical flow motion parameter estimation with angular rate data provided by a strapdown inertial measurement unit (IMU). A discrete Kalman filter in feedforward configuration is used for optimal fusion of the two data sources. Performance evaluations are conducted by a simulated video truth model (capturing the effects of image translation, rotation, …

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Synthesis, Interdiction, And Protection Of Layered Networks, Kevin T. Kennedy Sep 2009

Synthesis, Interdiction, And Protection Of Layered Networks, Kevin T. Kennedy

Theses and Dissertations

This research developed the foundation, theory, and framework for a set of analysis techniques to assist decision makers in analyzing questions regarding the synthesis, interdiction, and protection of infrastructure networks. This includes extension of traditional network interdiction to directly model nodal interdiction; new techniques to identify potential targets in social networks based on extensions of shortest path network interdiction; extension of traditional network interdiction to include layered network formulations; and develops models/techniques to design robust layered networks while considering trade-offs with cost. These approaches identify the maximum protection/disruption possible across layered networks with limited resources, find the most robust layered …

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Characterizing Component Hiding Using Ancestral Entropy, Jason A. Williams Mar 2009

Characterizing Component Hiding Using Ancestral Entropy, Jason A. Williams

Theses and Dissertations

In this research, the problem of software protection and the attributes that define that protection is considered. Specifically, how to protect programs defined as structural combinational logic gates. Obfuscation is one technique for protecting such circuits and involves replacing an original circuit with a functionally equivalent variant that has some definable hiding property. The difficulty of reverse engineering versus identifying and recovering the original components or sub-circuits within an original circuit is compared. With a polymorphic circuit engine that produces semantically equivalent variations of standard benchmark circuits the level of component hiding across variants with different physical configurations is determined …

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Methodology For Value-Driven Enterprise Architecture Development Goals: Application To Dodaf Framework, Justin W. Osgood Mar 2009

Methodology For Value-Driven Enterprise Architecture Development Goals: Application To Dodaf Framework, Justin W. Osgood

Theses and Dissertations

The Department of Defense Architectural Framework (DoDAF) describes 29 distinct views but offers limited guidance on view selection to meet system needs. This research extends the Value-Driven Enterprise Architecture Score (VDEA-Score) from a descriptive, evaluation protocol toward a prescriptive one by evaluating each DoDAF view and its contribution to the overall objective of the completed architecture. This extension of VDEA is referred to as VDEA-Development Goals (VDEA-DG). The program manager or other decision-makers may use this insight to justify the allocation of resources to the development of specific architecture views considered to provide maximum value. This research provides insight into …

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A Taxonomy For And Analysis Of Anonymous Communications Networks, Douglas J. Kelly Mar 2009

A Taxonomy For And Analysis Of Anonymous Communications Networks, Douglas J. Kelly

Theses and Dissertations

Any entity operating in cyberspace is susceptible to debilitating attacks. With cyber attacks intended to gather intelligence and disrupt communications rapidly replacing the threat of conventional and nuclear attacks, a new age of warfare is at hand. In 2003, the United States acknowledged that the speed and anonymity of cyber attacks makes distinguishing among the actions of terrorists, criminals, and nation states difficult. Even President Obama’s Cybersecurity Chief-elect recognizes the challenge of increasingly sophisticated cyber attacks. Now through April 2009, the White House is reviewing federal cyber initiatives to protect US citizen privacy rights. Indeed, the rising quantity and ubiquity …

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Decisive Routing And Admission Control According To Quality Of Service Constraints, Cindy C. Reese Mar 2009

Decisive Routing And Admission Control According To Quality Of Service Constraints, Cindy C. Reese

Theses and Dissertations

This research effort examines, models, and proposes options to enhance command and control for decision makers when applied to the communications network. My goal is to research the viability of combining three students’ past research efforts and expanding and enhancing those efforts. The area of this research is predicting a snapshot of the communications network, context-aware routing between network nodes, and Quality of Service-based routing optimization in order to create an intelligent routing protocol platform. It will consolidate efforts from an Intelligent Agent Based Framework to Maximize Information Utility by Captain John Pecarina, Dialable Cryptography for Wireless Networks by Major …

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Unified Behavior Framework In An Embedded Robot Controller, Stephen S. Lin Mar 2009

Unified Behavior Framework In An Embedded Robot Controller, Stephen S. Lin

Theses and Dissertations

Robots of varying autonomy have been used to take the place of humans in dangerous tasks. While robots are considered more expendable than human beings, they are complex to develop and expensive to replace if lost. Recent technological advances produce small, inexpensive hardware platforms that are powerful enough to match robots from just a few years ago. There are many types of autonomous control architecture that can be used to control these hardware platforms. One in particular, the Unified Behavior Framework, is a flexible, responsive control architecture that is designed to simplify the control system’s design process through behavior module …

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Using A Multiobjective Approach To Balance Mission And Network Goals Within A Delay Tolerant Network Topology, Anthony L. Larweck Mar 2009

Using A Multiobjective Approach To Balance Mission And Network Goals Within A Delay Tolerant Network Topology, Anthony L. Larweck

Theses and Dissertations

This thesis investigates how to incorporate aspects of an Air Tasking Order (ATO), a Communications Tasking Order (CTO), and a Network Tasking Order (NTO) within a cognitive network framework. This was done in an effort to aid the commander and or network operator by providing automation for battlespace management to improve response time and potential inconsistent problem resolution. In particular, autonomous weapon systems such as unmanned aerial vehicles (UAVs) were the focus of this research This work implemented a simple cognitive process by incorporating aspects of behavior based robotic control principles to solve the multi-objective optimization problem of balancing both …

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Using Covert Means To Establish Cybercraft Command And Control, Bradley D. Sevy Mar 2009

Using Covert Means To Establish Cybercraft Command And Control, Bradley D. Sevy

Theses and Dissertations

With the increase in speed and availability of computers, our nation's computer and information systems are being attacked with increased sophistication. The Air Force Research Laboratory (AFRL) Information Directorate (RI) is researching a next generation network defense architecture, called Cybercraft, that provides automated and trusted cyber defense capabilities for AF network assets. This research we consider the issues to protect or obfuscate command and control aspects of Cybercraft. In particular, we present a methodology to hide aspects of Cybercraft platform initialization in context to formation of hierarchical, peer-to-peer groups that collectively form the Cybercraft network. Because malicious code networks (known …

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The Benefits Of A Network Tasking Order In Combat Search And Rescue Missions, Murat Gocmen Mar 2009

The Benefits Of A Network Tasking Order In Combat Search And Rescue Missions, Murat Gocmen

Theses and Dissertations

Networked communications play a crucial role in United States Armed Forces operations. As the military moves towards more network centric (Net-Centric) operations, it becomes increasingly important to use the network as effectively as possible with respect to the overall mission. This thesis advocates the use of a Network Tasking Order (NTO), which allows operators to reason about the network based on asset movement, capabilities, and communication requirements. These requirements are likely to be derived from the Air Tasking Order (ATO), which gives insight into the plan for physical assets in a military mission. In this research we illustrate the benefit …

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Evaluation Of An Opnet Model For Unmanned Aerial Vehicle Networks, Clifton M. Durham Mar 2009

Evaluation Of An Opnet Model For Unmanned Aerial Vehicle Networks, Clifton M. Durham

Theses and Dissertations

The concept of Unmanned Aerial Vehicles (UAVs) was first used as early as the American Civil War, when the North and the South unsuccessfully attempted to launch balloons with explosive devices. Since the American Civil War, the UAV concept has been used in all subsequent military operations. Over the last few years, there has been an explosion in the use of UAVs in military operations, as well as civilian and commercial applications. UAV Mobile Ad Hoc Networks (MANETs) are fast becoming essential to conducting Network-Centric Warfare (NCW). As of October 2006, coalition UAVs, exclusive of hand-launched systems, had flown almost …

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Low Probability Of Intercept Waveforms Via Intersymbol Dither Performance Under Multipath Conditions, Jonathan K. Keen Mar 2009

Low Probability Of Intercept Waveforms Via Intersymbol Dither Performance Under Multipath Conditions, Jonathan K. Keen

Theses and Dissertations

This thesis examines the effects of multipath interference on Low Probability of Intercept (LPI) waveforms generated using intersymbol dither. LPI waveforms are designed to be difficult for non-cooperative receivers to detect and manipulate, and have many uses in secure communications applications. In prior research, such a waveform was designed using a dither algorithm to vary the time between the transmission of data symbols in a communication system. This work showed that such a method can be used to frustrate attempts to use non-cooperative receiver algorithms to recover the data. This thesis expands on prior work by examining the effects of …

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The Modular Clock Algorithm For Blind Rendezvous, Nicholas C. Theis Mar 2009

The Modular Clock Algorithm For Blind Rendezvous, Nicholas C. Theis

Theses and Dissertations

This thesis examines the problem in initializing communications whereby cognitive radios need to find common spectrum with other cognitive radios, a process known as frequency rendezvous. It examines the rendezvous problem as it exists in a dynamic spectrum access cognitive network. Specifically, it addresses the problem of rendezvous in an infrastructureless environment. A new algorithm, the modular clock algorithm, is developed and analyzed as a solution for the simple rendezvous environment model, coupled with a modified version for environment models with less information. The thesis includes a taxonomy of commonly used environment models, and analysis of previous efforts to solve …

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Image Processing For Multiple-Target Tracking On A Graphics Processing Unit, Michael A. Tanner Mar 2009

Image Processing For Multiple-Target Tracking On A Graphics Processing Unit, Michael A. Tanner

Theses and Dissertations

Multiple-target tracking (MTT) systems have been implemented on many different platforms, however these solutions are often expensive and have long development times. Such MTT implementations require custom hardware, yet offer very little flexibility with ever changing data sets and target tracking requirements. This research explores how to supplement and enhance MTT performance with an existing graphics processing unit (GPU) on a general computing platform. Typical computers are already equipped with powerful GPUs to support various games and multimedia applications. However, such GPUs are not currently being used in desktop MTT applications. This research explores if and how a GPU can …

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Numerical Analysis For Relevant Features In Intrusion Detection (Narfid), Jose Andres Gonzalez Mar 2009

Numerical Analysis For Relevant Features In Intrusion Detection (Narfid), Jose Andres Gonzalez

Theses and Dissertations

Identification of cyber attacks and network services is a robust field of study in the machine learning community. Less effort has been focused on understanding the domain space of real network data in identifying important features for cyber attack and network service classification. Motivations for such work allow for anomaly detection systems with less requirements on data “sniffed” off the network, extraction of features from the traffic, reduced learning time of algorithms, and ideally increased classification performance of anomalous behavior. This thesis evaluates the usefulness of a good feature subset for the general classification task of identifying cyber attacks and …

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Voice Traffic Over Mobile Ad Hoc Networks: A Performance Analysis Of The Optimized Link State Routing Protocol, Lady Noreen P. Santos Mar 2009

Voice Traffic Over Mobile Ad Hoc Networks: A Performance Analysis Of The Optimized Link State Routing Protocol, Lady Noreen P. Santos

Theses and Dissertations

This thesis investigates the performance of the Optimized Link State Routing (OLSR) protocol on Voice over Internet Protocol (VoIP) applications in Mobile Ad hoc Networks (MANETs). Using VoIP over MANETs takes advantage of the mobility and versatility of a MANET environment and the flexibility and interoperability a digital voice format affords. Research shows that VoIP-like traffic can be routed through an ad hoc network using the Ad hoc On-demand Distance Vector routing protocol. This research determines the suitability of OLSR as a routing protocol for MANETs running VoIP applications. Representative VoIP traffic is submitted to a MANET and end-to-end delay …

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Dynamic Interactions For Network Visualization And Simulation, Cigdem Yetisti Mar 2009

Dynamic Interactions For Network Visualization And Simulation, Cigdem Yetisti

Theses and Dissertations

Most network visualization suites do not interact with a simulator, as it executes. Nor do they provide an effective user interface that includes multiple visualization functions. The subject of this research is to improve the network visualization presented in the previous research [5] adding these capabilities to the framework. The previous network visualization did not have the capability of altering specific visualization characteristics, especially when detailed observations needed to be made for a small part of a large network. Searching for a network event in this topology might cause large delays leading to lower quality user interface. In addition to …

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Stochastic Estimation And Control Of Queues Within A Computer Network, Mingook Kim Mar 2009

Stochastic Estimation And Control Of Queues Within A Computer Network, Mingook Kim

Theses and Dissertations

Captain Nathan C. Stuckey implemented the idea of the stochastic estimation and control for network in OPNET simulator. He used extended Kalman filter to estimate packet size and packet arrival rate of network queue to regulate queue size. To validate stochastic theory, network estimator and controller is designed by OPNET model. These models validated the transient queue behavior in OPNET and work of Kalman filter by predicting the queue size and arrival rate. However, it was not enough to verify a theory by experiment. So, it needed to validate the stochastic control theory with other tools to get high validity. …

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Optimized Robust Adaptive Networks In Supervisory Control And Data Acquisition Systems, Luis A. Oquendo Class Mar 2009

Optimized Robust Adaptive Networks In Supervisory Control And Data Acquisition Systems, Luis A. Oquendo Class

Theses and Dissertations

This thesis investigates the application of a Exponential Weighted Moving Average (EWMA) to be used as a memory buffer in conjunction with Special Protection Schemes (SPS) using the Electric Power and Communication Synchronizing Simulator (EPOCHS). It is proposed that using an SPS incorporating EWMA can compensate for the network layer lack of guarantee of packet delivery and provide for the stability and integrity of the power grid under a catastrophic event. The performance of the proposed SPS is evaluated using a discrete event computer simulation developed using the NS2 network simulator and the Power System Simulator for Engineering (PSS/E) power …

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Enhancing The Ns-2 Network Simulator For Near Real-Time Control Feedback And Distributed Simulation Breaks, John S. Weir Mar 2009

Enhancing The Ns-2 Network Simulator For Near Real-Time Control Feedback And Distributed Simulation Breaks, John S. Weir

Theses and Dissertations

A network simulator coupled with a visualization package enables the human visual system to analyze the results of network modeling as a supplement to analytical data analysis. This research takes the next step in network simulator and visualization suite interaction. A mediator (or run-time infrastructure (RTI) in the literature) provides researchers the potential to interact with a simulation as it executes. Utilizing TCP/IP sockets, the mediator has the capability to connect multiple visualization packages to a single simulation. This new tool allows researchers to change simulation parameters on the y without restarting the network simulation.

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The Evaluation Of Rekeying Protocols Within The Hubenko Architecture As Applied To Wireless Sensor Networks, Cory J. Antosh Mar 2009

The Evaluation Of Rekeying Protocols Within The Hubenko Architecture As Applied To Wireless Sensor Networks, Cory J. Antosh

Theses and Dissertations

This thesis investigates the impact of using three different rekeying protocols–pair-wise, hierarchical, and Secure Lock within a wireless sensor network (WSN) under the Hubenko architecture. Using a Matlab computer simulation, the impact of the three rekeying protocols on the number of bits transmitted across the network and the amount of battery power consumed in WSN nodes during rekey operations is investigated. Baseline pair-wise rekeying performance can be improved by using either Secure Lock or hierarchical rekeying. The best choice depends on the size of the WSN and the size of the key used. Hierarchical rekeying is the best choice for …

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Chip To Chip Optical Interconnection Using Mems Mirrors, Tod V. Laurvick Feb 2009

Chip To Chip Optical Interconnection Using Mems Mirrors, Tod V. Laurvick

Theses and Dissertations

This experiment explores the use of MEMS mirrors to direct subsurface optical signals to another device and reception of those signals for use in chip to chip communications. Devices were built in PolyMUMPs to control horizontal and vertical beam direction and tilting in the outgoing signal and MEMS beam splitters for the incoming signal. Several elements of the outgoing beam path were successful and those which needed improvement indicate a high probability of success with limited trials needed and currently successful design elements could still be improved within the scope of PolyMUMPs. The incoming beam path elements were not successful …

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Adaptive Control Of Woofer-Tweeter Adaptive Optics, Jimmie J. Perez Feb 2009

Adaptive Control Of Woofer-Tweeter Adaptive Optics, Jimmie J. Perez

Theses and Dissertations

Adaptive optics applies advanced sensing and control to improve the ability of optical systems to collect images through a turbulent atmosphere. The results of this research effort demonstrate that the combination of two recent approaches improves the performance of adaptive optics in directed energy and laser communication scenarios. The first approach is adaptive control, which offers improved performance over fixed-gain controllers in the presence of rapidly changing turbulence. The second approach incorporated into the study is a dual-mirror system. The two mirrors are a high-bandwidth, low-actuator-stroke (tweeter) mirror and a low-bandwidth, large actuator-stroke (woofer) mirror. The woofer-tweeter combination allows for …

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Automated Virtual Machine Introspection For Host-Based Intrusion Detection, Brett A. Pagel Feb 2009

Automated Virtual Machine Introspection For Host-Based Intrusion Detection, Brett A. Pagel

Theses and Dissertations

This thesis examines techniques to automate configuration of an intrusion detection system utilizing hardware-assisted virtualization. These techniques are used to detect the version of a running guest operating system, automatically configure version-specific operating system information needed by the introspection library, and to locate and monitor important operating system data structures. This research simplifies introspection library configuration and is a step toward operating system independent introspection. An operating system detection algorithm and Windows virtual machine system service dispatch table monitor are implemented using the Xen hypervisor and a modified version of the XenAccess library. All detection and monitoring is implemented from …

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Subjective Audio Quality Over A Secure Ieee 802.11n Draft 2.0 Wireless Local Area Network, Benjamin W. Ramsey Feb 2009

Subjective Audio Quality Over A Secure Ieee 802.11n Draft 2.0 Wireless Local Area Network, Benjamin W. Ramsey

Theses and Dissertations

This thesis investigates the quality of audio generated by a G.711 codec and transmission over an IEEE 802.11n draft 2.0 wireless local area network (WLAN). Decline in audio quality due to additional calls or by securing the WLAN with transport mode Internet Protocol Security (IPsec) is quantified. Audio quality over an IEEE 802.11n draft 2.0 WLAN is also compared to that of IEEE 802.11b and IEEE 802.11g WLANs under the same conditions. Audio quality is evaluated by following International Telecommunication Union Telecommunication Standardization Sector (ITU-T) Recommendation P.800, where human subjects rate audio clips recorded during various WLAN configurations. The Mean …

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An Fpga-Based System For Tracking Digital Information Transmitted Via Peer-To-Peer Protocols, Karl R. Schrader Feb 2009

An Fpga-Based System For Tracking Digital Information Transmitted Via Peer-To-Peer Protocols, Karl R. Schrader

Theses and Dissertations

This thesis addresses the problem of identifying and tracking digital information that is shared using peer-to-peer file transfer and Voice over IP (VoIP) protocols. The goal of the research is to develop a system for detecting and tracking the illicit dissemination of sensitive government information using file sharing applications within a target network, and tracking terrorist cells or criminal organizations that are covertly communicating using VoIP applications. A digital forensic tool is developed using an FPGA-based embedded software application. The tool is designed to process file transfers using the BitTorrent peer-to-peer protocol and VoIP phone calls made using the Session …

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