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A Formal Object Model For Layered Networks To Support Verification And Simulation, Rasha M. B. E. Morsi Apr 2002

A Formal Object Model For Layered Networks To Support Verification And Simulation, Rasha M. B. E. Morsi

Electrical & Computer Engineering Theses & Dissertations

This work presents an abstract formal model of the interconnection structure of the Open Systems Interconnection Reference Model (OSI-RM) developed using Object-Oriented modeling principles permitting it to serve as a re-usable platform in supporting the development of simulations and formal methods applied to layered network protocols. A simulation of the object model using MODSIM III was developed and Prototype Verification System (PVS) was used to show the applicability of the object model to formal methods by formally specifying and verifying a Global Systems for Mobile communications (GSM) protocol. This application has proved to be successful in two aspects. The first …

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Association Of 3d Visualization With Discrete Event Simulation, Krishna Chaitanya Kunam Apr 2002

Association Of 3d Visualization With Discrete Event Simulation, Krishna Chaitanya Kunam

Electrical & Computer Engineering Theses & Dissertations

Three-dimensional visualization provides simulation users with imagery that is closely related to their direct human experience. 3D visualization of simulations therefore has several advantages: it assists the developer in verifying and debugging the simulation; it often aids the analyst in gaining a better understanding of system performance; and it is especially important in explaining simulation results to the customer. This work presents a method of associating 3D visualizations to discrete event simulations for process simulations. A software system called 3DGen is developed that automates the process of generating a 3D visualization for a discrete event simulation. The 3DGen system is …

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The Development Of An Enterprise Supply Chain Model For Naval Warship Construction, Rex A. Wallen Apr 2002

The Development Of An Enterprise Supply Chain Model For Naval Warship Construction, Rex A. Wallen

Computational Modeling & Simulation Engineering Theses & Dissertations

The utilization of computer simulation in the shipbuilding industry is not a new concept and many shipyards in the US and around the world are using simulation tools in a variety of ways with various levels of success. In other industries, computer simulation has proven itself as a powerful tool for reducing non-value added activities and promises to become more prominent in its use as a resource management tool. Its use in the manufacturing of outfitting components in the construction of Naval warships has had limited success due mainly to the inherent nature of ship construction, especially shipyards engaged in …

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Embedded Software Programming To Develop A Command Line User Interface For Monitoring And Debugging A Manually Driven Gas Regulator Control System, Syed N. Hyder Apr 2002

Embedded Software Programming To Develop A Command Line User Interface For Monitoring And Debugging A Manually Driven Gas Regulator Control System, Syed N. Hyder

Electrical & Computer Engineering Theses & Dissertations

This thesis presents a complete embedded programming model and software codes for a command-line user interface for CONCOA's gas regulator control system. Control Corporation of America (CONCOA) manufactures high-pressure gas regulators, which mechanically control the pressure at their outlets. Since the control system is based on mechanical regulators, adding or stopping gas flow from the system can cause manifold fluctuation that could further cause the pressure to rise or fall with time. The main motivation for developing a command line user interface is to provide a centralized computer control to monitor and debug the gas regulator control system electronically by …

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Traffic Simulation Using Arena, Shanti Yelamanchi Apr 2002

Traffic Simulation Using Arena, Shanti Yelamanchi

Electrical & Computer Engineering Theses & Dissertations

Many traffic simulation tools exist for developing traffic simulations; these tools can be divided broadly into two categories — macro simulation tools and micro simulation tools. These two categories of simulation tools are directed at modeling the extremes of traffic systems: very large systems and very small systems. There is a class of intermediate-sized transportation networks for which neither category of simulation tools might perform adequately. Additionally these specialized traffic simulation tools have a high learning curve. For developing medium sized traffic simulations in a short period of time, one might choose to use a familiar general-purpose discrete event simulation …

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The Value Of Ontology-Based, Service-Oriented, Distributed Systems In A High Bandwidth Environment, Steven J. Gollery, Jens G. Pohl Mar 2002

The Value Of Ontology-Based, Service-Oriented, Distributed Systems In A High Bandwidth Environment, Steven J. Gollery, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

No abstract provided.

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Western Michigan University Occupational Therapy Department Web Page, Holly Pietrzak, Melissa Byrne Mar 2002

Western Michigan University Occupational Therapy Department Web Page, Holly Pietrzak, Melissa Byrne

Honors Theses

Website designed for WMU's Occupational Therapy department.

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Rapid Heterogeneous Ad Hoc Connection Establishment: Accelerating Bluetooth Inquiry Using Irda, Trevor Clifton, Derek D. Joos, Charles D. Knutson, Ryan W. Woodings Mar 2002

Rapid Heterogeneous Ad Hoc Connection Establishment: Accelerating Bluetooth Inquiry Using Irda, Trevor Clifton, Derek D. Joos, Charles D. Knutson, Ryan W. Woodings

Faculty Publications

Bluetooth device discovery is a time-intensive phase of the Bluetooth connection-establishment procedure. In this paper we propose a technique that integrates existing IrDA technology with Bluetooth technology to improve the ad hoc connection establishment time of Bluetooth devices. We accomplish this improvement by first establishing an IrDA connection between two devices equipped with both Bluetooth and IrDA capabilities and then exchanging Bluetooth device discovery information via the established IrDA connection. As a result of this cooperative exchange, the devices are able to bypass the time-intensive Bluetooth device discovery procedure. Our research shows that IrDA-assisted Bluetooth connection establishment is up to …

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Characterizing Usage Of A Campus-Wide Wireless Network, David Kotz, Kobby Essien Mar 2002

Characterizing Usage Of A Campus-Wide Wireless Network, David Kotz, Kobby Essien

Computer Science Technical Reports

Wireless local-area networks (WLANs) are increasingly common, but little is known about how they are used. A clear understanding of usage patterns in real WLANs is critical information to those who develop, deploy, and manage WLAN technology, as well as those who develop systems and application software for wireless networks. This paper presents results from the largest and most comprehensive trace of network activity in a large, production wireless LAN. For eleven weeks we traced the activity of nearly two thousand users drawn from a general campus population, using a campus-wide network of 476 access points spread over 161 buildings. …

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Applying Kinodynamic Randomized Motion Planning With A Dynamic Priority System To Multi-Robot Space Systems, Christopher M. Clark, Tim Bretl, Stephen Rock Mar 2002

Applying Kinodynamic Randomized Motion Planning With A Dynamic Priority System To Multi-Robot Space Systems, Christopher M. Clark, Tim Bretl, Stephen Rock

Computer Science and Software Engineering

Presents a new motion planning system that can construct collision-free trajectories for groups of robots in dynamic environments, without global knowledge or high-bandwidth communication. The robots plan within a confined environment that consists of stationary and moving obstacles. Each robot plans independently using Kinodynamic Randomized Motion Planner techniques to construct its own trajectory that is free of collisions with moving obstacles and other robots. To resolve conflicts between robot trajectories, a new Dynamic Priority System (DPS) is introduced which gives the right of way to the robot whose local workspace is the most crowded. The kinodynamic randomized motion planner allows …

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Building Web Applications With Servlets And Javaserver Pages, David S. Janzen Mar 2002

Building Web Applications With Servlets And Javaserver Pages, David S. Janzen

Computer Science and Software Engineering

Servlets and JavaServer Pages provide the ability to dynamically generate web pages using the Java programming language. Among other benefits, the use of Java on the server-side allows the web developer to directly implement object-oriented designs, utilize multiple threads of execution, and employ JDBC to communicate with a database. This tutorial will introduce Servlets and JavaServer Pages through UML diagrams, code samples, and an example web application.

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Investigation Of Cooperative Behavior In Autonomous Wide Search Munitions, Robert E. Dunkel Iii Mar 2002

Investigation Of Cooperative Behavior In Autonomous Wide Search Munitions, Robert E. Dunkel Iii

Theses and Dissertations

The purpose of this research is to investigate the effectiveness of wide-area search munitions in various scenarios using different cooperative behavior algorithms. The general scenario involves multiple autonomous munitions searching for an unknown number of targets of different priority in unknown locations. Three cooperative behavior algorithms are used in each scenario: no cooperation, cooperative attack only, and cooperative classification and attack. In the cooperative cases, the munitions allocate tasks on-line as a group, using linear programming techniques to determine the optimum allocation. Each munition provides inputs to the task allocation routine in the form of probabilities of successfully being able …

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Ontological Engineering And Mapping In Multiagent Systems Development, Jonathan M. Dileo Mar 2002

Ontological Engineering And Mapping In Multiagent Systems Development, Jonathan M. Dileo

Theses and Dissertations

Multiagent systems have received much attention in recent years due to their advantages in complex, distributed environments. Previous work at the Air Force Institute of Technology has developed a methodology for analyzing, designing, and developing multiagent systems, called Multiagent Systems Engineering (MaSE). MaSE currently does not address the information domain of the system, which is an integral part of designing proper system execution. This research extends the MaSE methodology to include the use of ontologies for information domain specification. The extensions allow the designer to specify information flow by using objects from the ontology as parameters in agent conversations. The …

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Enumerating Foldings And Unfoldings Between Polygons And Polytopes, Erik D. Demaine, Martin L. Demaine, Anna Lubiw, Joseph O'Rourke Mar 2002

Enumerating Foldings And Unfoldings Between Polygons And Polytopes, Erik D. Demaine, Martin L. Demaine, Anna Lubiw, Joseph O'Rourke

Computer Science: Faculty Publications

We pose and answer several questions concerning the number of ways to fold a polygon to a polytope, and how many polytopes can be obtained from one polygon; and the analogous questions for unfolding polytopes to polygons. Our answers are, roughly: exponentially many, or nondenumerably infinite.

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A Collaborative Visualization Framework Using Jini™ Technology, Chad M. Harris Mar 2002

A Collaborative Visualization Framework Using Jini™ Technology, Chad M. Harris

Theses and Dissertations

It is difficult to achieve mutual understanding of complex information between individuals that are separated geographically. Two well-known techniques commonly used to deal with this difficultly are collaboration and information visualization. This thesis develops a generic flexible framework that supports both collaboration and information visualization. It introduces the Collaborative Visualization Environment (COVE) framework, which simplifies the development of real-time synchronous multi-user applications by decoupling the elements of collaboration from the application. This allows developers to focus on building applications and leave the difficulties of collaboration (i.e., concurrency controls, user awareness, session management, etc.) to the framework. The framework uses an …

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Using Relational Schemata In A Computer Immune System To Detect Multiple-Packet Network Intrusions, John L. Bebo Mar 2002

Using Relational Schemata In A Computer Immune System To Detect Multiple-Packet Network Intrusions, John L. Bebo

Theses and Dissertations

Given the increasingly prominent cyber-based threat, there are substantial research and development efforts underway in network and host-based intrusion detection using single-packet traffic analysis. However, there is a noticeable lack of research and development in the intrusion detection realm with regard to attacks that span multiple packets. This leaves a conspicuous gap in intrusion detection capability because not all attacks can be found by examining single packets alone. Some attacks may only be detected by examining multiple network packets collectively, considering how they relate to the "big picture," not how they are represented as individual packets. This research demonstrates a …

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Application Of Information Retrieval Techniques To Heterogeneous Databases In The Virtual Distributed Laboratory, Rodney D. Lykins Mar 2002

Application Of Information Retrieval Techniques To Heterogeneous Databases In The Virtual Distributed Laboratory, Rodney D. Lykins

Theses and Dissertations

The Department of Defense (DoD) maintains thousands of Synthetic Aperture Radar (SAR), Infrared (IR), Hyper-Spectral intelligence imagery and Electro-Optical (EO) target signature data. These images are essential to evaluating and testing individual algorithm methodologies and development techniques within the Automatic Target Recognition (ATR) community. The Air Force Research Laboratory Sensors Directorate (AFRL/SN) has proposed the Virtual Distributed Laboratory (VDL) to maintain a central collection of the associated imagery metadata and a query mechanism to retrieve the desired imagery. All imagery metadata is stored in relational database format for access from agencies throughout the federal government and large civilian universities. Each …

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Mrpc: Maximizing Network Lifetime For Reliable Routing In Wireless Environments, Archan Misra, Suman Banerjee Mar 2002

Mrpc: Maximizing Network Lifetime For Reliable Routing In Wireless Environments, Archan Misra, Suman Banerjee

Research Collection School Of Computing and Information Systems

We propose MRPC, a new power-aware routing algorithm for energy-efficient routing that increases the operational lifetime of multi-hop wireless networks. In contrast to conventional power-aware algorithms, MRPC identifies the capacity of a node not just by its residual battery energy, but also by the expected energy spent in reliably forwarding a packet over a specific link. Such a formulation better captures scenarios where link transmission costs also depend on physical distances between nodes and the link error rates. Using a max-min formulation, MRPC selects the path that has the largest packet capacity at the 'critical' node (the one with the …

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An Intelligent Middleware For Linear Correlation Discovery, Cecil Chua, Roger Hsiang-Li Chiang, Ee Peng Lim Mar 2002

An Intelligent Middleware For Linear Correlation Discovery, Cecil Chua, Roger Hsiang-Li Chiang, Ee Peng Lim

Research Collection School Of Computing and Information Systems

Although it is widely accepted that research from data mining, knowledge discovery, and data warehousing should be synthesized, little research addresses the integration of existing data management and analysis software. We develop an intelligent middleware that facilitates linear correlation discovery, the discovery of associations between attributes and attribute groups. This middleware integrates data management and data analysis tools to improve traditional data analysis in three perspectives: (1) identify appropriate linear correlation functions to perform based on the semantics of a data set; (2) execute appropriate functions contained in the data analysis packages; and (3) derive useful knowledge from data analysis.

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Idmp-Based Fast Handoffs And Paging In Ip-Based 4g Mobile Networks, Archan Misra, Subir Das, Anthony Mcauley, Sajal K. Das Mar 2002

Idmp-Based Fast Handoffs And Paging In Ip-Based 4g Mobile Networks, Archan Misra, Subir Das, Anthony Mcauley, Sajal K. Das

Research Collection School Of Computing and Information Systems

We consider the use of our previously proposed Intra-Domain Mobility Management Protocol (IDMP) in fourth-generation mobile networks. On evaluating the heterogeneous access technologies, cellular layouts, and application characteristics of 4G environments, we realize a need to reduce both handoff latency and the frequency of mobility-related signaling. We first present IDMP's fast intradomain handoff mechanism that uses a duration-limited proactive packet multicasting solution. We quantify the expected buffering requirements of our proposed multicasting scheme for typical 4G network characteristics and compare it with alternative IP-based fast handoff solutions. We also present a paging scheme under IDMP that replicates the current cellular …

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B2b E-Commerce Revisited: Leading Perspectives On The Key Issues And Research Directions, Qizhi Dai, Robert J. Kauffman Mar 2002

B2b E-Commerce Revisited: Leading Perspectives On The Key Issues And Research Directions, Qizhi Dai, Robert J. Kauffman

Research Collection School Of Computing and Information Systems

The application of Internet technologies for the conduct of interfirm business transactions has given rise to a boom in business-to-business (B2B) electronic commerce. Yet, although there are many success stories that have been reported over the past several years, the progress of B2B e-commerce has been hindered by unanticipated technical, organizational, economic and legal challenges that diminish value. In this article, we report on a series of interviews with leading academic researchers and industry senior managers who are in a unique position to make sense of key issues and offer useful insights. The respondents provide their views on the efficacy …

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A Visual Meta-Language For Generic Modeling, Hakan Canli Mar 2002

A Visual Meta-Language For Generic Modeling, Hakan Canli

Theses and Dissertations

This research examines the usefulness of a visual meta-language (VLGM Visual Language for Generic Modeling) developed for the specification of components and relations in a modeling domain. The language is designed to allow software tools to interpret specifications and automatically provide modeling environments. VLGM makes use of the object-orientated software engineering methodology. It defines four types of special classes and three types of relations between them. Data types and primitive types are allocated with several attributes to provide restrictions and enable consistency checks over models. As part of this research a software tool was designed. The tool provides a workspace …

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Bubble World - A Novel Visual Information Retrieval Technique, Christopher L. Van Berendonck Mar 2002

Bubble World - A Novel Visual Information Retrieval Technique, Christopher L. Van Berendonck

Theses and Dissertations

With the tremendous growth of published electronic information sources in the last decade and the unprecedented reliance on this information to succeed in day-to-day operations, comes the expectation of finding the right information at the right time. Sentential interfaces are currently the only viable solution for searching through large infospheres of unstructured information, however, the simplistic nature of their interaction model and lack of cognitive amplification they can provide severely limit the performance of the interface. Visual information retrieval systems are emerging as possible candidate replacements for the more traditional interfaces, but many lack the cognitive framework to support the …

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Categorizing Network Attacks Using Pattern Classification Algorithms, George E. Noel Iii Mar 2002

Categorizing Network Attacks Using Pattern Classification Algorithms, George E. Noel Iii

Theses and Dissertations

The United States Air Force relies heavily on computer networks for many day-to-day activities. Many of these networks are affected by various types of attacks that can be launched from anywhere on the globe. The rising prominence of organizations such as the AFCERT and the MAJCOM NOSCs is evidence of an increasing realization among the Air Force leadership that protecting our computer networks is vitally important. A critical requirement for protecting our networks is the ability to detect attacks and intrusion attempts. This research is an effort to refine a portion of an AFIT-developed intrusion detection system known as the …

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An Integrated Architecture And Feature Selection Algorithm For Radial Basis Neural Networks, Timothy D. Flietstra Mar 2002

An Integrated Architecture And Feature Selection Algorithm For Radial Basis Neural Networks, Timothy D. Flietstra

Theses and Dissertations

There are two basic ways to control an Unmanned Combat Aerial Vehicle (UCAV) as it searches for targets: allow the UCAV to act autonomously or employ man-in-the-loop control. There are also two target sets of interest: fixed or mobile targets. This research focuses on UCAV-based targeting of mobile targets using man-in-the-loop control. In particular, the interest is in how levels of satellite signal latency or signal degradation affect the ability to accurately track, target, and attack mobile targets. This research establishes a weapon effectiveness model assessing targeting inaccuracies as a function of signal latency and/or signal degradation. The research involved …

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An Interactive Decision Support System For Scheduling Fighter Pilot Training, Cuong T. Nguyen Mar 2002

An Interactive Decision Support System For Scheduling Fighter Pilot Training, Cuong T. Nguyen

Theses and Dissertations

The U.S. Air Force is developing Modular Aircraft Support System (MASS) program to replace the current Aerospace Ground Equipment (AGE). AGE supplies electricity, nitrogen, hydraulics and other support equipment to maintenance activities at the flight line. Current AGE makes up one-third of the deployment footprint. AGE is also mostly aircraft specific, and has reliability problems. The MASS alternative focuses on modularity based on a plug-and-play approach. The technological improvements and possible reduction in the footprint make MASS a good alternative. The AF has to determine now, whether MASS can supply similar functionality and decrease the deployment footprint to theater, while …

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Context Aggregation And Dissemination In Ubiquitous Computing Systems, Guanling Chen, David Kotz Feb 2002

Context Aggregation And Dissemination In Ubiquitous Computing Systems, Guanling Chen, David Kotz

Computer Science Technical Reports

Many ``ubiquitous computing'' applications need a constant flow of information about their environment to be able to adapt to their changing context. To support these ``context-aware'' applications we propose a graph-based abstraction for collecting, aggregating, and disseminating context information. The abstraction models context information as events, produced by sources and flowing through a directed acyclic graph of event-processing operators and delivered to subscribing applications. Applications describe their desired event stream as a tree of operators that aggregate low-level context information published by existing sources into the high-level context information needed by the application. The operator graph is thus the dynamic …

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Solar: A Pervasive-Computing Infrastructure For Context-Aware Mobile Applications, Guanling Chen, David Kotz Feb 2002

Solar: A Pervasive-Computing Infrastructure For Context-Aware Mobile Applications, Guanling Chen, David Kotz

Computer Science Technical Reports

Emerging pervasive computing technologies transform the way we live and work by embedding computation in our surrounding environment. To avoid increasing complexity, and allow the user to concentrate on her tasks, applications must automatically adapt to their changing \emph{context}, the physical and computational environment in which they run. To support these ``context-aware'' applications we propose a graph-based abstraction for collecting, aggregating, and disseminating context information. The abstraction models context information as \emph{events}, which are produced by \emph{sources}, flow through a directed acyclic graph of event-processing \emph{operators}, and are delivered to subscribing applications. Applications describe their desired event stream as a …

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Controlling Access To Pervasive Information In The “Solar” System, Kazuhiro Minami, David Kotz Feb 2002

Controlling Access To Pervasive Information In The “Solar” System, Kazuhiro Minami, David Kotz

Computer Science Technical Reports

Pervasive-computing infrastructures necessarily collect a lot of context information to disseminate to their context-aware applications. Due to the personal or proprietary nature of much of this context information, however, the infrastructure must limit access to context information to authorized persons. In this paper we propose a new access-control mechanism for event-based context-distribution infrastructures. The core of our approach is based on a conservative information-flow model of access control, but users may express discretionary relaxation of the resulting access-control list (ACL) by specifying relaxation functions. This combination of automatic ACL derivation and user-specified ACL relaxation allows access control to be determined …

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Integrating Symbol-Oriented And Sub-Symbolic Reasoning Methods Into Hybrid Systems, Franz J. Kurfess Feb 2002

Integrating Symbol-Oriented And Sub-Symbolic Reasoning Methods Into Hybrid Systems, Franz J. Kurfess

Computer Science and Software Engineering

Knowledge representation and reasoning methods in artificial intelligence almost exclusively rely on symbol-oriented methods: Statements describing aspects and objects of the system to be modeled are represented through symbols (mostly text strings), and these symbols are stored in a computer, and manipulated according to the inference rules prescribed by the reasoning method. This works reasonably well in situations where knowledge is available in explicit form, typically through experts or written documents. In situations where knowledge is only available implicitly, e.g. in large data sets, other methods, often based on statistical approaches, have been used more successfully. Many of these methods …

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