5,014 research outputs found

    Метод синтезу моделей станів об’єктів програмного забезпечення автоматизованої системи обробки цифрових зображень

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    This article proposes a method for the synthesis of the behavior of software objects models (SOM) for the developed object-oriented software systems for automated digital image processing in order to avoid systemic and algorithmic errors in the design phase of a software system, as well as to reduce the time of its development. The process of constructing the SOM proceeding from its finite-state representation is viewed from the standpoint of abstract synthesis of an automata’s finite state. Thus, the specialties of the synthesis of finite automaton SOM, the construction of the map defining a plurality of channels management class of objects, the order to bring it to an automata, the construction of the canonical set of events and their regular expressions to display defining a plurality of channels management of software objects class for object oriented software system are considered and justified. Переважна більшість даних, які обробляються сучасними інфокомунікаційними системами, є графічними. Істотна частка з них – цифрові зображення, які характеризуються великими обсягами. Таким чином, виникає потреба їх представлення у компактному вигляді, що забезпечить зменшення навантаження на канали зв’язку, підвищення оперативності доставки та скорочення обсягів пам’яті, необхідної для зберігання даних. Вирішенням цієї проблеми є розроблення з використанням об’єктно- орієнтованої технології автоматизованої системи обробки цифрових зображень (АСОЗ), на етапі проектування якої постає актуальна задача побудови моделей поведінки екземплярів класів об’єктно- орієнтованого програмного забезпечення (ООПЗ) задля уникнення системних та алгоритмічних помилок, а також скорочення часу розроблення. Тож, мета роботи полягає в розробленні метода синтезу моделей станів програмних об’єктів об’єктно-орієнтованого програмного забезпечення АСОЗ. Процес побудови моделі станів програмних об’єктів (МСО) ООПЗ, виходячи з її скінченно- автоматного представлення, розглянуто з погляду абстрактного синтезу скінченного автомата. У роботі викладені й обґрунтовані особливості синтезу скінченно-автоматної МСО ООПЗ, побудова відображення, яке визначає множину каналів керування класу об’єктів, та порядок приведення його до автоматного виду, а також побудова канонічної множини подій і їх регулярних виразів для відображення, яке визначає множину каналів керування класу програмних об’єктів. На основі отриманих результатів дослідження запропоновано метод синтезу моделей станів програмних об’єктів ООПЗ. Запропонований метод забезпечує формалізацію процесу визначення станів та їх взаємозв’язків у життєвому циклі екземпляра класу ООПЗ, а також дозволяє зменшити трудомісткість процесу розробки динамічної компоненти комплексної моделі ООПЗ під час її проектування на логічному рівні

    ARMD Workshop on Materials and Methods for Rapid Manufacturing for Commercial and Urban Aviation

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    This report documents the goals, organization and outcomes of the NASA Aeronautics Research Mission Directorates (ARMD) Materials and Methods for Rapid Manufacturing for Commercial and Urban Aviation Workshop. The workshop began with a series of plenary presentations by leaders in the field of structures and materials, followed by concurrent symposia focused on forecasting the future of various technologies related to rapid manufacturing of metallic materials and polymeric matrix composites, referred to herein as composites. Shortly after the workshop, questionnaires were sent to key workshop participants from the aerospace industry with requests to rank the importance of a series of potential investment areas identified during the workshop. Outcomes from the workshop and subsequent questionnaires are being used as guidance for NASA investments in this important technology area

    An environment for object-oriented real-time system design

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    A concise object-oriented method for the development of real-time systems has been composed. Hardware components are modelled by (software) base objects; base objects are controlled by a hierarchy of coordinator objects, expressed in an organizational diagram. The behaviour of objects is specified by state transition diagrams. This approach considerably promotes requirements analysis and communication with the customer. A CASE tool has been constructed with diagram editors for graphical specifications of real-time systems. The tool can generate executable code for PLCs from these graphical specifications; reuse of previous results is supported by the repository function of the tool. Experiences attained in practice with method and tool show that time spent in system testing and installation is reduced considerabl

    Buckling Testing and Analysis of Honeycomb Sandwich Panel Arc Segments of a Full-Scale Fairing Barrel Part 4: Six-ply Out-of-Autoclave Facesheets

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    Four honeycomb sandwich panel types, representing 1/16th arc segments of a 10-m diameter barrel section of the Heavy Lift Launch Vehicle (HLLV), were manufactured and tested under the NASA Composites for Exploration program and the NASA Constellation Ares V program. Two configurations were chosen for the panels: 6-ply facesheets with 1.125 in. honeycomb core and 8-ply facesheets with 1.000 in. honeycomb core. Additionally, two separate carbon fiber/epoxy material systems were chosen for the facesheets: in-autoclave IM7/977-3 and out-of-autoclave T40-800b/5320-1. Smaller 3 ft. by 5 ft. panels were cut from the 1/16th barrel sections. These panels were tested under compressive loading at the NASA Langley Research Center (LaRC). Furthermore, linear eigenvalue and geometrically nonlinear finite element analyses were performed to predict the compressive response of each 3 ft. by 5 ft. panel. This manuscript summarizes the experimental and analytical modeling efforts pertaining to the panels composed of 6-ply, T40-800b/5320-1 facesheets (referred to as Panels D). To improve the robustness of the geometrically nonlinear finite element model, measured surface imperfections were included in the geometry of the model. Both the linear and nonlinear models yield good qualitative and quantitative predictions. Additionally, it was correctly predicted that the panel would fail in buckling prior to failing in strength. Furthermore, three-dimensional (3D) effects on the compressive response of the panel were studied

    An approach to the analysis and deisgn of an intelligent tutoring system using an object-oriented methodology

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    A true Intelligent Tutoring System is difficult to produce in today\u27s technological environment. This thesis reviews various theoretical methods and strategies that could be employed in performing the analysis and design of an Intelligent Tutoring System. An overview of the basic concepts of Object-Oriented Analysis and Design are provided in this thesis. The notation system provided by these concepts are utilized. The Object-Oriented Analysis and Design methods that are employed create a basis for an implementation of an Intelligent Tutoring System

    Rigorous object-oriented analysis

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    Object-oriented methods for analysis, design and programming are commonly used by software engineers. Formal description techniques, however, are mainly used in a research environment. We have investigated how rigour can be introduced into the analysis phase of the software development process by combining object-oriented analysis (OOA) methods with formal description techniques. The main topics of this investigation are a formal interpretation of the OOA constructs using LOTOS, a mathematical definition of the basic OOA concepts using a simple denotational semantics and a new method for object- oriented analysis that we call the Rigorous Object-Oriented Analysis method (ROOA). The LOTOS interpretation of the OOA concepts is an intrinsic part of the ROOA method. It was designed in such a way that software engineers with no experience in LOTOS, can still use ROOA. The denotational semantics of the concepts of object-oriented analysis illuminates the formal syntactic transformations within ROOA and guarantees that the basic object- oriented concepts can be understood independently of the specification language we use. The ROOA method starts from a set of informal requirements and an object model and produces a formal object-oriented analysis model that acts as a requirements specification. The resulting formal model integrates the static, dynamic and functional properties of a system in contrast to existing OOA methods which are informal and produce three separate models that are difficult to integrate and keep consistent. ROOA provides a systematic development process, by proposing a set of rules to be followed during the analysis phase. During the application of these rules, auxiliary structures are created to help in tracing the requirements through to the final formal model. As LOTOS produces executable specifications, prototyping can be used to check the conformance of the specification against the original requirements and to detect inconsistencies, omissions and ambiguities early in the development process

    Application of product modelling - seen from a work preparation viewpoint

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    DATA REPLICATION IN DISTRIBUTED SYSTEMS USING OLYMPIAD OPTIMIZATION ALGORITHM

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    Achieving timely access to data objects is a major challenge in big distributed systems like the Internet of Things (IoT) platforms. Therefore, minimizing the data read and write operation time in distributed systems has elevated to a higher priority for system designers and mechanical engineers. Replication and the appropriate placement of the replicas on the most accessible data servers is a problem of NP-complete optimization. The key objectives of the current study are minimizing the data access time, reducing the quantity of replicas, and improving the data availability. The current paper employs the Olympiad Optimization Algorithm (OOA) as a novel population-based and discrete heuristic algorithm to solve the replica placement problem which is also applicable to other fields such as mechanical and computer engineering design problems. This discrete algorithm was inspired by the learning process of student groups who are preparing for the Olympiad exams. The proposed algorithm, which is divide-and-conquer-based with local and global search strategies, was used in solving the replica placement problem in a standard simulated distributed system. The 'European Union Database' (EUData) was employed to evaluate the proposed algorithm, which contains 28 nodes as servers and a network architecture in the format of a complete graph. It was revealed that the proposed technique reduces data access time by 39% with around six replicas, which is vastly superior to the earlier methods. Moreover, the standard deviation of the results of the algorithm's different executions is approximately 0.0062, which is lower than the other techniques' standard deviation within the same experiments
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