1,063 research outputs found

    METHODOLOGY OF SYNTHESIS OF PACKING MACHINES FOR FOOD PRODUCTS BASED ON MULTICRITERIAL ANALYSIS

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    The complex of technical means for optimization synthesis of assembling of a packing machine of separate functional modules has been developed. The method of synthesis of a packing machine, based on criterial assessment of separate functional modules (FM), combined by two main assessment groups, has been offered. FM may be selected and calculated by the program of consumption, based on the overall equipment effectiveness (OEE) criterion. An example of synthesis, based on the offered method, takes into account variants of choice of ready functional modules, based on the hierarchic structure of a module of roll packing material supply. The method takes into account the systemic approach to analysis of equipment constructions for packing fine-piece and piece food products in a consumption package. The synthesis of FM assembling as conceptual models, abstract ones, reflecting the construction structure and connections between separate elements – functional devices (FD) – has been offered. The optimal assembling of the functional device in the structure of the functional module of roll packing material supply has been determined. As a result of solving this problem, a FM1 prototype has been created. At conducting the comparative analysis with the existent equipment, the automatic functional device has been modeled. The use of the OEE criterion with joint properties that reflects the generalized assessment of a packing machine or functional module with a maximin (minimax) criterion by the compromise principle has been substantiated. The analysis is grounded on the idea of optimality of each module or device of the machine for packing food products at adding each next functional module to its composition. The program of assessment calculation of the package equipment with the complex assessment criterion OEE for different assembling of FMi machines for packing piece and fine-piece products has been developed. The FM of roll film material supply with using a microprocessor managing device that maintains a sinusoidal law of movement of a stretching roll of the packing machine has been developed. Optimal characteristics of the technical system have been determined. Results, obtained at processing experimental data, confirm adequacy of the offered method for assessing assembling solution

    Transformation of logic programs: Foundations and techniques

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    AbstractWe present an overview of some techniques which have been proposed for the transformation of logic programs. We consider the so-called “rules + strategies” approach, and we address the following two issues: the correctness of some basic transformation rules w.r.t. a given semantics and the use of strategies for guiding the application of the rules and improving efficiency. We will also show through some examples the use and the power of the transformational approach, and we will briefly illustrate its relationship to other methodologies for program development

    Rule-based Methodologies for the Specification and Analysis of Complex Computing Systems

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    Desde los orígenes del hardware y el software hasta la época actual, la complejidad de los sistemas de cálculo ha supuesto un problema al cual informáticos, ingenieros y programadores han tenido que enfrentarse. Como resultado de este esfuerzo han surgido y madurado importantes áreas de investigación. En esta disertación abordamos algunas de las líneas de investigación actuales relacionada con el análisis y la verificación de sistemas de computación complejos utilizando métodos formales y lenguajes de dominio específico. En esta tesis nos centramos en los sistemas distribuidos, con un especial interés por los sistemas Web y los sistemas biológicos. La primera parte de la tesis está dedicada a aspectos de seguridad y técnicas relacionadas, concretamente la certificación del software. En primer lugar estudiamos sistemas de control de acceso a recursos y proponemos un lenguaje para especificar políticas de control de acceso que están fuertemente asociadas a bases de conocimiento y que proporcionan una descripción sensible a la semántica de los recursos o elementos a los que se accede. También hemos desarrollado un marco novedoso de trabajo para la Code-Carrying Theory, una metodología para la certificación del software cuyo objetivo es asegurar el envío seguro de código en un entorno distribuido. Nuestro marco de trabajo está basado en un sistema de transformación de teorías de reescritura mediante operaciones de plegado/desplegado. La segunda parte de esta tesis se concentra en el análisis y la verificación de sistemas Web y sistemas biológicos. Proponemos un lenguaje para el filtrado de información que permite la recuperación de informaciones en grandes almacenes de datos. Dicho lenguaje utiliza información semántica obtenida a partir de ontologías remotas para re nar el proceso de filtrado. También estudiamos métodos de validación para comprobar la consistencia de contenidos web con respecto a propiedades sintácticas y semánticas. Otra de nuestras contribuciones es la propuesta de un lenguaje que permite definir y comprobar automáticamente restricciones semánticas y sintácticas en el contenido estático de un sistema Web. Finalmente, también consideramos los sistemas biológicos y nos centramos en un formalismo basado en lógica de reescritura para el modelado y el análisis de aspectos cuantitativos de los procesos biológicos. Para evaluar la efectividad de todas las metodologías propuestas, hemos prestado especial atención al desarrollo de prototipos que se han implementado utilizando lenguajes basados en reglas.Baggi ., M. (2010). Rule-based Methodologies for the Specification and Analysis of Complex Computing Systems [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/8964Palanci

    Methodologies for transformations and memoing in applicative languages

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    Constraint-based verification of imperative programs

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    work presented in the context of the European Master’s program in Computational Logic, as the partial requirement for obtaining Master of Science degree in Computational LogicThe continuous reduction in the cost of computing ever since the first days of computers has resulted in the ubiquity of computing systems today; there is no any sphere of life in the daily routine of human beings that is not directly or indirectly influenced by computer systems anymore. But this high reliance on computers has not come without a risk to the society or a challenge to computer scientists. As many computer systems of today are safety critical, it is crucial for computer scientists to make sure that computer systems, both the hardware and software components, behave correctly under all circumstances. In this study, we are interested in techniques of program verification that are aimed at ensuring the correctness of the software component. In this work, constraint programming techniques are used to device a program verification framework where constraint solvers play the role of typical verification tools. The programs considered are written in some subset of Java, and their specifications are written in some subset of Java Modeling Language(JML). In our framework, the program verification process has two principal steps: constraint generation and constraint solving. A program together with its specification is first parsed into a system of constraints. And then, the system of constraints is processed using constraint solvers so that the correctness of the original program is proved to hold, or not, based on the outcome of the constraint solving. The performance of our framework is compared with other well-known program verification tools using standard benchmarks, and our framework has performed quite well for most of the cases

    An integrated approach to high integrity software verification.

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    Computer software is developed through software engineering. At its most precise, software engineering involves mathematical rigour as formal methods. High integrity software is associated with safety critical and security critical applications, where failure would bring significant costs. The development of high integrity software is subject to stringent standards, prescribing best practises to increase quality. Typically, these standards will strongly encourage or enforce the application of formal methods. The application of formal methods can entail a significant amount of mathematical reasoning. Thus, the development of automated techniques is an active area of research. The trend is to deliver increased automation through two complementary approaches. Firstly, lightweight formal methods are adopted, sacrificing expressive power, breadth of coverage, or both in favour of tractability. Secondly, integrated solutions are sought, exploiting the strengths of different technologies to increase automation. The objective of this thesis is to support the production of high integrity software by automating an aspect of formal methods. To develop tractable techniques we focus on the niche activity of verifying exception freedom. To increase effectiveness, we integrate the complementary technologies of proof planning and program analysis. Our approach is investigated by enhancing the SPARK Approach, as developed by Altran Praxis Limited. Our approach is implemented and evaluated as the SPADEase system. The key contributions of the thesis are summarised below: • Configurable and Sound - Present a configurable and justifiably sound approach to software verification. • Cooperative Integration - Demonstrate that more targeted and effective automation can be achieved through the cooperative integration of distinct technologies. • Proof Discovery - Present proof plans that support the verification of exception freedom. • Invariant Discovery - Present invariant discovery heuristics that support the verification of exception freedom. • Implementation as SPADEase - Implement our approach as SPADEase. • Industrial Evaluation - Evaluate SPADEase against both textbook and industrial subprograms

    A heuristic-based approach to code-smell detection

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    Encapsulation and data hiding are central tenets of the object oriented paradigm. Deciding what data and behaviour to form into a class and where to draw the line between its public and private details can make the difference between a class that is an understandable, flexible and reusable abstraction and one which is not. This decision is a difficult one and may easily result in poor encapsulation which can then have serious implications for a number of system qualities. It is often hard to identify such encapsulation problems within large software systems until they cause a maintenance problem (which is usually too late) and attempting to perform such analysis manually can also be tedious and error prone. Two of the common encapsulation problems that can arise as a consequence of this decomposition process are data classes and god classes. Typically, these two problems occur together – data classes are lacking in functionality that has typically been sucked into an over-complicated and domineering god class. This paper describes the architecture of a tool which automatically detects data and god classes that has been developed as a plug-in for the Eclipse IDE. The technique has been evaluated in a controlled study on two large open source systems which compare the tool results to similar work by Marinescu, who employs a metrics-based approach to detecting such features. The study provides some valuable insights into the strengths and weaknesses of the two approache

    Philosophical foundations of the Death and Anti-Death discussion

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    Perhaps there has been no greater opportunity than in this “VOLUME FIFTEEN of our Death And Anti-Death set of anthologies” to write about how might think about life and how to avoid death. There are two reasons to discuss “life”, the first being enhancing our understanding of who we are and why we may be here in the Universe. The second is more practical: how humans meet the physical challenges brought about by the way they have interacted with their environment. Many persons discussing “life” beg the question about what “life” is. Surely, when one discusses how to overcome its opposite, death, they are not referring to another “living” thing such as a plant. There seems to be a commonality, though, and it is this commonality is one needing elaboration. It ostensibly seems to be the boundary condition separating what is completely passive (inert) from what attempts to maintain its integrity, as well as fulfilling other conditions we think “life” has. In our present discussion, there will be a reminder that it by no means has been unequivocally established what life really is by placing quotes around the word, namely, “life”. Consider it a tag representing a bundle of philosophical ideas that will be unpacked in this paper
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