450,888 research outputs found

    Naked Object File System (NOFS): A Framework to Expose an Object-Oriented Domain Model as a File System

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    We present Naked Objects File System (NOFS), a novel framework that allows a developer to expose a domain model as a file system by leveraging the Naked Objects design principle. NOFS allows a developer to construct a file system without having to understand or implement all details related to normal file systems development. In this paper we explore file systems frameworks and object-oriented frameworks in a historical context and present an example domain model using the framework. This paper is based on a fully-functional implementation that is distributed as free/open source software, including virtual machine images to demonstrate and study the referenced example file systems

    An Open-Domain Dialog Act Taxonomy

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    This document defines the taxonomy of dialog acts that are necessary to encode domain-independent dialog moves in the context of a task-oriented, open-domain dialog. Such taxonomy is formulated to satisfy two complementary requirements: on the one hand, domain independence, i.e. the power to cover all the range of possible interactions in any type of conversation (particularly conversation oriented to the performance of tasks). On the other hand, the ability to instantiate a concrete set of tasks as defined by a specific knowledge base (such as an ontology of domain concepts and actions) and within a particular language. For the modeling of dialog acts, inspiration is taken from several well-known dialog annotation schemes, such as DAMSL (Core & Allen, 1997), TRAINS (Traum, 1996) and VERBMOBIL (Alexandersson et al., 1997)

    Addition of Structured Records to the UNIX™ and MS-DOS™ File Systems

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    A file system consists of operating system code supporting the I/O operations that open, close, create, read and write to files. Record oriented I/O is not a feature of either the UNIX or the MS-DOS native file system. The data is stored by the file system as a sequence of bytes. It is the task of the user to design an application dependent structure on the file system. In the case of logically related fixed or variable length data, a record structure is desirable. This thesis describes a set of extensions to the UNIX and the MS-DOS file systems that supply a record structure to these native file systems. The descriptions of both the UNIX and the MS-DOS native file systems are followed by the extensions to each file system. Program code is provided to demonstrate the MS-DOS extensions

    Geoscience after IT: Part L. Adjusting the emerging information system to new technology

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    Coherent development depends on following widely used standards that respect our vast legacy of existing entries in the geoscience record. Middleware ensures that we see a coherent view from our desktops of diverse sources of information. Developments specific to managing the written word, map content, and structured data come together in shared metadata linking topics and information types

    MatSWMM - An open-source toolbox for designing real-time control of urban drainage systems

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    This manuscript describes the MatSWMM toolbox, an open-source Matlab, Python, and LabVIEW-based software package for the analysis and design of real-time control (RTC) strategies in urban drainage systems (UDS). MatSWMM includes control-oriented models of UDS, and the storm water management model (SWMM) of the US Environmental Protection Agency (EPA), as well as systematic-system edition functionalities. Furthermore, MatSWMM is also provided with a population-dynamics-based controller for UDS with three of the fundamental dynamics, i.e., the Smith, projection, and replicator dynamics. The simulation algorithm, and a detailed description of the features of MatSWMM are presented in this manuscript in order to illustrate the capabilities that the tool has for educational and research purposes.Peer ReviewedPostprint (author's final draft

    An open platform for rapid-prototyping protection and control schemes with IEC 61850

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    Communications is becoming increasingly important to the operation of protection and control schemes. Although offering many benefits, using standards-based communications, particularly IEC 61850, in the course of the research and development of novel schemes can be complex. This paper describes an open-source platform which enables the rapid prototyping of communications-enhanced schemes. The platform automatically generates the data model and communications code required for an intelligent electronic device to implement a publisher-subscriber generic object-oriented substation event and sampled-value messaging. The generated code is tailored to a particular system configuration description (SCD) file, and is therefore extremely efficient at runtime. It is shown here how a model-centric tool, such as the open-source Eclipse Modeling Framework, can be used to manage the complexity of the IEC 61850 standard, by providing a framework for validating SCD files and by automating parts of the code generation process. The flexibility and convenience of the platform are demonstrated through a prototype of a real-time, fast-acting load-shedding scheme for a low-voltage microgrid network. The platform is the first open-source implementation of IEC 61850 which is suitable for real-time applications, such as protection, and is therefore readily available for research and education

    An analysis of the factors of conversion from a batch-processing, tape-oriented retrieval system to an on-line, real-time system

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    The factors for converting a batch-processing, tape-oriented document reference system to an-on-line, real-time system are discussed. The factors analyzed are file structures, file addressing, file maintenance, communication, scheduling, and modular programming structures. The levels of design for the individual factors are illustrated in order to show the complexities of conversion to an on-line, real-time system. It is concluded that system conversion from a batch-processing, tape-oriented system to an on-line, real-time system requires a total systems redesign, not a modification of the existing system. A vector model for system conversion is presented. The vector quantities of the model represent the factor levels and their probable costs-for implementation. It is concluded from the analysis and the vector model that interrelations between the factor levels must be followed for an operationally complete system conversion

    Hysteresis at low Reynolds number: the onset of 2D vortex shedding

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    Hysteresis has been observed in a study of the transition between laminar flow and vortex shedding in a quasi-two dimensional system. The system is a vertical, rapidly flowing soap film which is penetrated by a rod oriented perpendicular to the film plane. Our experiments show that the transition from laminar flow to a periodic K\'arm\'an vortex street can be hysteretic, i.e. vortices can survive at velocities lower than the velocity needed to generate them.Comment: RevTeX file 4 pages + 5 (encapsulated postscript) figures. to appear in Phys.Rev.E, Rapid Communicatio
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