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Framework development for providing accessibility to qualitative spatial calculi

Jan, Sahib
Fonte: Universidade Nova de Lisboa Publicador: Universidade Nova de Lisboa
Tipo: Dissertação de Mestrado
Publicado em 07/02/2011 ENG
Relevância na Pesquisa
16.68%
Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.; Qualitative spatial reasoning deals with knowledge about an infinite spatial domain using a finite set of qualitative relations without using numerical computation. Qualitative knowledge is relative knowledge where we obtain the knowledge on the basis of comparison of features with in the object domain rather then using some external scales. Reasoning is an intellectual facility by which, conclusions are drawn from premises and is present in our everyday interaction with the geographical world. The kind of reasoning that human being relies on is based on commonsense knowledge in everyday situations. During the last decades a multitude of formal calculi over spatial relations have been proposed by focusing on different aspects of space like topology, orientation and distance. Qualitative spatial reasoning engines like SparQ and GQR represents space and reasoning about the space based on qualitative spatial relations and bring qualitative reasoning closer to the geographic applications. Their relations and certain operations defined in qualitative calculi use to infer new knowledge on different aspects of space. Today GIS does not support common-sense reasoning due to limitation for how to formalize spatial inferences. It is important to focus on common sense geographic reasoning...

Design principles of semantic binary database management systems

Vasilevsky, Dmitry
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
26.34%
The Semantic Binary Data Model (SBM) is a viable alternative to the now-dominant relational data model. SBM would be especially advantageous for applications dealing with complex interrelated networks of objects provided that a robust efficient implementation can be achieved. This dissertation presents an implementation design method for SBM, algorithms, and their analytical and empirical evaluation. Our method allows building a robust and flexible database engine with a wider applicability range and improved performance. ^ Extensions to SBM are introduced and an implementation of these extensions is proposed that allows the database engine to efficiently support applications with a predefined set of queries. A New Record data structure is proposed. Trade-offs of employing Fact, Record and Bitmap Data structures for storing information in a semantic database are analyzed. ^ A clustering ID distribution algorithm and an efficient algorithm for object ID encoding are proposed. Mapping to an XML data model is analyzed and a new XML-based XSDL language facilitating interoperability of the system is defined. Solutions to issues associated with making the database engine multi-platform are presented. An improvement to the atomic update algorithm suitable for certain scenarios of database recovery is proposed. ^ Specific guidelines are devised for implementing a robust and well-performing database engine based on the extended Semantic Data Model. ^

XML storage and retrieval using the semantic binary object -oriented database system (SEM-ODB)

Yang, Li
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
26.79%
Over the past five years, XML has been embraced by both the research and industrial community due to its promising prospects as a new data representation and exchange format on the Internet. The widespread popularity of XML creates an increasing need to store XML data in persistent storage systems and to enable sophisticated XML queries over the data. The currently available approaches to addressing the XML storage and retrieval issue have the limitations of either being not mature enough (e.g. native approaches) or causing inflexibility, a lot of fragmentation and excessive join operations (e.g. non-native approaches such as the relational database approach). ^ In this dissertation, I studied the issue of storing and retrieving XML data using the Semantic Binary Object-Oriented Database System (Sem-ODB) to leverage the advanced Sem-ODB technology with the emerging XML data model. First, a meta-schema based approach was implemented to address the data model mismatch issue that is inherent in the non-native approaches. The meta-schema based approach captures the meta-data of both Document Type Definitions (DTDs) and Sem-ODB Semantic Schemas, thus enables a dynamic and flexible mapping scheme. Second, a formal framework was presented to ensure precise and concise mappings. In this framework...

Binary data transfer performance over high-latency networks using web service attachments

Zhang, D.; Coddington, P.; Wendelborn, A.
Fonte: IEEE; USA Publicador: IEEE; USA
Tipo: Conference paper
Publicado em //2007 EN
Relevância na Pesquisa
26.27%
One of the objectives of e-Research is to help scientists to accomplish their research, including scientific experiments, more effectively and efficiently. Web services provide communication between different platforms by using standardized SOAP message protocols. Hence, it is often productive to implement web service interfaces for the integration of experimental infrastructure into a collaborative e-Science framework. In this context, transfer and management of experimental data is an important problem. SOAP messaging is primarily oriented towards XML character data, with binary data transmitted with, for example, a base64 character encoding. However, as scientific experiments often generate binary data, transferring binary information by applying an encoding algorithm can slow down the performance of the system. The notion of web service attachment, has been introduced to solve this problem. In this paper, we illustrate how we use web services with attachments to improve binary data transfer performance. We present results of tests, using Axis2 and XFire APIs, conducted over a campus IAN, an inter-city WAN, and an intercontinental WAN. We also make some comparison with the use of GridFTP.; Donglai Zhang, Coddington, P. and Wendelborn...

Analysis of binary XML suitability for NATO tactical messaging

Bayer, Matthew E.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
46.88%
The ability to efficiently transfer information among tactical systems is essential for network-centric operations. However, maintaining interoperability among heterogeneous networks and applications is a challenging issue, especially for large enterprises such as the US Department of Defense and NATO. Each of these organizations maintain extensive communication networks of tactical systems that process and manage all types of data. Additional complexity is added when considering that many systems are built with a variety of proprietary or legacy data formats. Establishing and maintaining interoperability is difficult. Using XML, many interoperability issues can now be successfully addressed. XML provides a self-describing way to effectively structure information that can be applied to compose diverse tactical communications. However, XML is inefficient for network transmission since it uses a text-based format which can consume more memory (and thus more bandwidth) than binary equivalents. In addition, parsing text-based documents is slow and computationally expensive. One potential solution is to use GZIP to reduce the file size before transmission. Unfortunately, this solution has limitations since it often provides suboptimal compression and also requires additional processing time when extracting data. Recent standardization efforts have identified promising new encodings for XML that use binary representations to reduce parsing time...

Performance comparison of relational and native-xml databases using the semantics of the land command and control information exchange data model (LC2IEDM)

Dieter, Jahn
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
36.52%
Approved for public release, distribution unlimited; Efforts to improve the military decision and action cycle have centered on automating the command and control process and improving interoperability among joint and coalition forces. However, information automation by itself can lead to increased operator overload when the way this information is stored and presented is not structured and consistently filtered. The majority of messaging systems store information in a document-centric free-text format that makes it difficult for command and control systems, relational databases, software agents and web portals to intelligently search the information. Consistent structure and semantic meaning is essential when integrating these capabilities. Military-grade implementations must also provide high performance. A widely accepted platform-independent technology standard for representing document-centric information is the Extensible Markup Language (XML). XML supports the structured representation of information in context through the use of metadata. By using an XML Schema generated from MIPâ s Land Command and Control Information Exchange Data Model (LC2IEDM), it is feasible to compare the syntactic strength of human-readable XML documents with the semantics of LC2IEDM as used within a relational database. The insert...

A configuration framework and implementation for the least privilege separation kernel

Quek, Chee Luan
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
16.52%
Approved for public release; distribution is unlimited; The Least Privilege Separation Kernel (LPSK) configuration vector defines the initial secure state and the operational configuration of the kernel, including its security policies. Enhancements made to the LPSK functional specification necessitated substantial changes to the configuration vector data format defined previously. Moreover, the earlier format used an ad-hoc syntax, which did not adhere to any standard. This work leverages Extensible Markup Language (XML) to standardize the configuration vector format. The new configuration vector format is depicted in a XML Schema, and its limitations are discussed. A more compact binary representation is defined, with an offline tool provided to generate binary configuration vectors for the target platform. Creation of a configuration vector file is a laborious and error-prone task. A good user interface can ease the process by removing underlying complexities from users. Pertinent features of XML editors were assessed in a survey. Using these as requirements, an XML editor with a suitable graphical user interface was selected.

DIS-XML: Moving DIS to Open Data Exchange Standards

McGregor, Don; Brutzman, Don; Armold, Adrian; Blais, Curtis L.
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Relevância na Pesquisa
26.63%
The Distributed Interactive Simulation (DIS) IEEE-1278.1 standard is used in many military simulations. The binary data format for DIS does not lend itself to use in emerging web services standards or data analysis and storage tools because the data format is not recognized by most general purpose data manipulation tools. We examine an alternate XML-based representation of DIS information. An XML representation unlocks legacy data by placing it in a standard data format, and thereby integrates with the many XML data transformation, storage, and analysis tools. An XML-based approach also allows easy generation of programming language Application Program Interfaces (APIs). The information contained in DIS PDUs can shift between any of several representations, including the binary IEEE- 1278.1 standard, XML, or programming language objects. The XML representation can be used in web services applications or passed over instant messaging channels. Initial tests demonstrate satisfactory performance.

DIS-XML, An XML Representation of Distributed Interactive Simulation Protocol Data Units

McGregor, Don; Blais, Curt; Brutzman, Don; Falash, Mark
Fonte: Monterey, California: Naval Postgraduate School. Publicador: Monterey, California: Naval Postgraduate School.
Tipo: Conferência ou Objeto de Conferência
Relevância na Pesquisa
26.34%
Simulation Interoperability Standards Organization (SISO) papers; DIS is a well-understood binary IEEE standard for exchanging information in military simulations. Binary format Protocol Data Units (PDUs) are exchanged in order to update positions of entities in 3D virtual worlds.

Evaluation of efficient XML interchange (EXI) for large datasets and as an alternative to binary JSON encodings

Hill, Bruce W.
Fonte: Monterey, California: Naval Postgraduate School Publicador: Monterey, California: Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
26.76%
Approved for public release; distribution is unlimited; Approved for public release; distribution is unlimited; Current and emerging Navy information concepts, including network-centric warfare and Navy Tactical Cloud, presume high network throughput and interoperability. The Extensible Markup Language (XML) addresses the latter requirement, but its verbosity is problematic for afloat networks. JavaScript Object Notation (JSON) is an alternative to XML common in web applications and some non-relational databases. Compact, binary encodings exist for both formats. Efficient XML Interchange (EXI) is a standardized, binary encoding of XML. Binary JSON (BSON) and Compact Binary Object Representation (CBOR) are JSON-compatible encodings. This work evaluates EXI compaction against both encodings, and extends evaluations of EXI for datasets up to 4 gigabytes. Generally, a configuration of EXI exists that produces a more compact encoding than BSON or CBOR. Tests show EXI compacts structured, non-multimedia data in Microsoft Office files better than the default format. The Navy needs to immediately consider EXI for use in web, sensor, and office document applications to improve throughput over constrained networks. To maximize EXI benefits, future work needs to evaluate EXI’s parameters...

Interconexión de redes de sensores inalámbricas y aplicaciones externas usando el lenguaje SENCOMLNG

Dopico Fernández, Iria
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: info:eu-repo/semantics/bachelorThesis; info:eu-repo/semantics/masterThesis Formato: application/pdf
SPA
Relevância na Pesquisa
16.34%
En este proyecto se pretende plantear e implementar un modelo para intercomunicar una red de sensores inalámbrica con una aplicación externa. Para ello se desarrollará una aplicación extremo a extremo de un sistema de comunicaciones para la solicitud de información de dispositivos inalámbricos. Las redes inalámbricas de sensores no están diseñadas para soportar grandes cargas de información, lo que supone un problema a la hora de desarrollar aplicaciones para este tipo de redes. Mediante la solución planteada en eXtensible Binary Enconding (XBE32) [1] y LWESP: Light- Weight Exterior Sensornet Protocol [2], se desarrollará una aplicación que solvente estos problemas, pudiendo utilizar el potencial de XML para realizar peticiones sin que esto afecte a la hora de realizar peticiones en la red de sensores final. Esta implementación se realizará mediante una aplicación Java para realizar peticiones en la red externa y la cual llevará un registro de las respuestas recibidas. Utilizará Internet para comunicarse con un equipo directamente conectado al punto de enlace con la red inalámbrica IEEE 802.15.4 sobre la que se realizarán las peticiones. El punto de enlace será el dispositivo que crea la red y estará formado por una placa con un microprocesador...

NPS AUV workbench: collaborative environment for autonomous underwater vehicles (AUV) mission planning and 3D visualization

Lee, Chin Siong
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xx, 197 p. : ill. (some col.)
Relevância na Pesquisa
26.46%
Approved for public release, distribution is unlimited; alities. The extensible Markup Language (XML) is used for data storage and message exchange, Extensible 3D (X3D) Graphics for visualization and XML Schema-based Binary Compression (XSBC) for data compression. The AUV Workbench provides an intuitive cross-platform-capable tool with extensibility to provide for future enhancements such as agent-based control, asynchronous reporting and communication, loss-free message compression and built-in support for mission data archiving. This thesis also investigates the Jabber instant messaging protocol, showing its suitability for text and file messaging in a tactical environment. Exemplars show that the XML backbone of this open-source technology can be leveraged to enable both human and agent messaging with improvements over current systems. Integrated Jabber instant messaging support makes the NPS AUV Workbench the first custom application supporting XML Tactical Chat (XTC). Results demonstrate that the AUV Workbench provides a capable testbed for diverse AUV technologies, assisting in the development of traditional single-vehicle operations and agent-based multiple-vehicle methodologies. The flexible design of the Workbench further encourages integration of new extensions to serve operational needs. Exemplars demonstrate how in-mission and post-mission event monitoring by human operators can be achieved via simple web page...

Efficient XML Interchange: Compact, Efficient, and Standards-Based XML

Snyder, Sheldon; McGregor, Don; Brutzman, Don
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Tipo: Trabalho em Andamento
EN_US
Relevância na Pesquisa
46.73%
Documents include Paper and Presentation.; Simulation Interoperability Standards Organization (SISO) SIW Conference Paper; XML has become a popular representation format for data, both in modeling and simulation and elsewhere. However, XML's design choice of a text-based format also makes XML data files much larger than binary files, making XML languages difficult to use in bandwidth-constrained military applications. This limitation has resulted in several ad-hoc attempts to make XML more compact, each of which tends to be incompatible with the other. Efficient XML Interchange (EXI) is a World Wide Web Consortium (W3C) Working Draft for the compact and efficient representation of the XML infoset. EXI is designed to be generally applicable to all XML documents, and lays the foundation for a unified format for compact XML document representation. This paper presents compactness results for several popular modeling and simulation XML file formats, including Distributed Interactive Simulation (DIS), Scalable Vector Graphics (SVG) and Extensible 3D Graphics (X3D). Recent commercial and open source EXI implementations are also described.; Naval Postgraduate School, Monterey, CA.

Utilization of forward error correction (FEC) techniques with extensible markup language (XML) schema-based binary compression (XSBC) technology

Norbraten, Terry D.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xvi, 173 p. : ill. (some col.)
Relevância na Pesquisa
36.68%
Approved for public release, distribution is unlimited; In order to plug-in current open sourced, open standard Java programming technology into the building blocks of the US Navy's ForceNet, first, stove-piped systems need to be made extensible to other pertinent applications and then a new paradigm of adopting extensible and cross-platform open technologies will begin to bridge gaps with old and new weapons systems. The battle-space picture in real time and with as much detail, or as little detail needed is now a current vital requirement. Access to this information via wireless laptop technology is here now. Transmission of data to increase the resolution of that battle-space snapshot will invariably be through noisy links. Noisy links such as found in the shallow water littoral regions of interest will be where Autonomous Underwater and Unmanned Underwater Vehicles (AUVs/UUVs) are gathering intelligence for the sea warrior in need of that intelligence. The battle-space picture built from data transmitted within these noisy and unpredictable acoustic regions demands efficiency and reliability features abstract to the user. To realize this efficiency Extensible Markup Language (XML) Schema-based Binary Compression (XSBC), in combination with Vandermode-based Forward Error Correction (FEC) erasure codes...

Efficient XML Interchange (EXI) compression and performance benefits : development, implementation and evaluation

Snyder, Sheldon L.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xxxii. 355 p. : ill. (color) ;
Relevância na Pesquisa
26.82%
Approved for public release; distribution is unlimited; The Department of Defense (DoD) Network-Centric data sharing strategy for the Global Information Grid (GIG) is to XMLize all data. The goal of this strategy is to ensure all data is visible, usable and interoperable, when and where needed, to accelerate decision cycles. However, this XML-based data approach comes at the cost of limiting real-time network edge device connectivity to the GIG because they are seldom able to meet the necessary bandwidth and processing requirements due to XML's intrinsic nature of being verbose and often complex to process. This research explores a powerful and robust solution to XML's network depth limits by means of the World Wide Web Consortium's (W3C) proposed alternative XML format, Efficient XML Interchange (EXI). The EXI format removes redundant tags and values from XML documents and encodes numeric content in a binary format. This format delivers significant file size savings and processing efficiencies compared to existing practices. The evolution of XML's path to EXI is summarized based on the results of the XML Binary Characterization (XBC) working group and the W3C's design points of XML. Followed are recommended steps for EXI development and enterprise integration...

A Binary Data Stream Scripting Language

Wang, Lihua; Capretz, Luz Fernando
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/07/2015
Relevância na Pesquisa
26.24%
Any file is fundamentally a binary data stream. A practical solution was achieved to interpret binary data stream. A new scripting language named Data Format Scripting Language (DFSL) was developed to describe the physical layout of the data in a structural, more intelligible way. On the basis of the solution, a generic software application was implemented; it parses various binary data streams according to their respective DFSL scripts and generates human-readable result and XML document for data sharing. Our solution helps eliminate the error-prone low-level programming, especially in the hardware devices or network protocol development/debugging processes.

ActorScript(TM) extension of C sharp (TM), Java(TM), and Objective C(TM): iAdaptive(TM) concurrency for antiCloud(TM) privacy and security

Hewitt, Carl
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.12%
ActorScript(TM) is a general purpose programming language for implementing discretionary, adaptive concurrency that manages resources and demand. It is differentiated from previous languages by the following: - Universality *** Ability to specify what Actors can do *** Specify interface between hardware and software *** Everything in the language is accomplished using message passing including the very definition of ActorScript itself *** Functional, Imperative, Logic, and Concurrent programming are integrated. *** Concurrency dynamically adapts to resources available and current load. *** Programs do not expose low-level implementation mechanisms such as threads, tasks, locks, cores, etc. *** Messages can be directly communicated without requiring indirection through brokers, channels, class hierarchies, mailboxes, pipes, ports, queues etc. *** Variable races are eliminated. *** Binary XML and JSON are data types. *** Application binary interfaces are afforded so that no identifier symbol need be looked up at runtime. - Safety and Security *** Programs are extension invariant, i.e., extending a program does not change its meaning. *** Applications cannot directly harm each other. - Performance *** Impose no overhead on implementation of Actor systems *** Message passing has essentially same overhead as procedure calling and looping. *** Allow execution to be dynamically adjusted for system load and capacity (e.g. cores) *** Locality because execution is not bound by a sequential global memory model *** Inherent concurrency because execution is not bound by communicating sequential processes *** Minimize latency along critical paths; Comment: Added explanation of facets of an Actor. Admin note: text overlap with arXiv:1008.1459

XML Compression via DAGs

Bousquet-Melou, Mireille; Lohrey, Markus; Maneth, Sebastian; Noeth, Eric
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 23/09/2013
Relevância na Pesquisa
26.57%
Unranked trees can be represented using their minimal dag (directed acyclic graph). For XML this achieves high compression ratios due to their repetitive mark up. Unranked trees are often represented through first child/next sibling (fcns) encoded binary trees. We study the difference in size (= number of edges) of minimal dag versus minimal dag of the fcns encoded binary tree. One main finding is that the size of the dag of the binary tree can never be smaller than the square root of the size of the minimal dag, and that there are examples that match this bound. We introduce a new combined structure, the hybrid dag, which is guaranteed to be smaller than (or equal in size to) both dags. Interestingly, we find through experiments that last child/previous sibling encodings are much better for XML compression via dags, than fcns encodings. We determine the average sizes of unranked and binary dags over a given set of labels (under uniform distribution) in terms of their exact generating functions, and in terms of their asymptotical behavior.; Comment: A short version of this paper appeared in the Proceedings of ICDT 2013

Global Numerical Constraints on Trees

Bárcenas, Everardo; Lavalle, Jesús
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
16.31%
We introduce a logical foundation to reason on tree structures with constraints on the number of node occurrences. Related formalisms are limited to express occurrence constraints on particular tree regions, as for instance the children of a given node. By contrast, the logic introduced in the present work can concisely express numerical bounds on any region, descendants or ancestors for instance. We prove that the logic is decidable in single exponential time even if the numerical constraints are in binary form. We also illustrate the usage of the logic in the description of numerical constraints on multi-directional path queries on XML documents. Furthermore, numerical restrictions on regular languages (XML schemas) can also be concisely described by the logic. This implies a characterization of decidable counting extensions of XPath queries and XML schemas. Moreover, as the logic is closed under negation, it can thus be used as an optimal reasoning framework for testing emptiness, containment and equivalence.

Validating XML Documents in the Streaming Model with External Memory

Konrad, Christian; Magniez, Frederic
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.49%
We study the problem of validating XML documents of size $N$ against general DTDs in the context of streaming algorithms. The starting point of this work is a well-known space lower bound. There are XML documents and DTDs for which $p$-pass streaming algorithms require $\Omega(N/p)$ space. We show that when allowing access to external memory, there is a deterministic streaming algorithm that solves this problem with memory space $O(\log^2 N)$, a constant number of auxiliary read/write streams, and $O(\log N)$ total number of passes on the XML document and auxiliary streams. An important intermediate step of this algorithm is the computation of the First-Child-Next-Sibling (FCNS) encoding of the initial XML document in a streaming fashion. We study this problem independently, and we also provide memory efficient streaming algorithms for decoding an XML document given in its FCNS encoding. Furthermore, validating XML documents encoding binary trees in the usual streaming model without external memory can be done with sublinear memory. There is a one-pass algorithm using $O(\sqrt{N \log N})$ space, and a bidirectional two-pass algorithm using $O(\log^2 N)$ space performing this task.; Comment: Change title. Remove a statement on a lower bound (now Conjecture 2 in Annexe B) since the proof was incomplete