Earliness penalties on a single machine subject to precedence constraints: SLK due date assignment

Abstract not available

A polynomial algorithm for the three-machine open shop with a bottleneck machine

Abstract not available

Ghost Machine: a Sound Performance

Ghost Machine is an encounter between a person and a machine in a suburban shed. The machine reveals the story of a man haunted by an image that seems to shift and change as it sits on the wall of his study. In an attempt to locate the origins of the image he builds a viewing machine to finally confront it. Ghost Machine is based on The Mezzotint (1904) by M.R James, retold as a suburban ghost story. It was part of SENSE at Mayfest in Bristol between 24th - 26th May 2013.

Two-stage open shop scheduling with a bottleneck machine

Abstract not available

Two-machine open shop scheduling with special transportation times

Abstract not available

Flow shop scheduling problems under machine-dependent precedence constraints

Abstract not available

The stochastic geometric machine model

This paper introduces the stochastic version of the Geometric Machine Model for the modelling of sequential, alternative, parallel (synchronous) and nondeterministic computations with stochastic numbers stored in a (possibly infinite) shared memory. The programming language L(D! 1), induced by the Coherence Space of Processes D! 1, can be applied to sequential and parallel products in order to provide recursive definitions for such processes, together with a domain-theoretic semantics of the Stochastic Arithmetic. We analyze both the spacial (ordinal) recursion, related to spacial modelling of the stochastic memory, and the temporal (structural) recursion, given by the inclusion relation modelling partial objects in the ordered structure of process construction.

The MUSE Machine -- an Architecture for Structured Data Flow Computation

Computers employing some degree of data flow organisation are now well established as providing a possible vehicle for concurrent computation. Although data-driven computation frees the architecture from the constraints of the single program counter, processor and global memory, inherent in the classic von Neumann computer, there can still be problems with the unconstrained generation of fresh result tokens if a pure data flow approach is adopted. The advantages of allowing serial processing for those parts of a program which are inherently serial, and of permitting a demand-driven, as well as data-driven, mode of operation are identified and described. The MUSE machine described here is a structured architecture supporting both serial and parallel processing which allows the abstract structure of a program to be mapped onto the machine in a logical way.

Calculating an Exceptional Machine

In previous work we showed how to verify a compiler for a small language with exceptions. In this article we show how to calculate, as opposed to verify, an abstract machine for this language. The key step is the use of Reynold's defunctionalization, an old program transformation technique that has recently been rejuvenated by the work of Danvy et al.

Transactions and schema evolution in a persistent object-oriented programming system

Applications are subject of a continuous evolution process with a profound impact on their underlining data model, hence requiring frequent updates in the applications' class structure and database structure as well. This twofold problem, schema evolution and instance adaptation, usually known as database evolution, is addressed in this thesis. Additionally, we address concurrency and error recovery problems with a novel meta-model and its aspect-oriented implementation. Modern object-oriented databases provide features that help programmers deal with object persistence, as well as all related problems such as database evolution, concurrency and error handling. In most systems there are transparent mechanisms to address these problems, nonetheless the database evolution problem still requires some human intervention, which consumes much of programmers' and database administrators' work effort. Earlier research works have demonstrated that aspect-oriented programming (AOP) techniques enable the development of flexible and pluggable systems. In these earlier works, the schema evolution and the instance adaptation problems were addressed as database management concerns. However, none of this research was focused on orthogonal persistent systems. We argue that AOP techniques are well suited to address these problems in orthogonal persistent systems. Regarding the concurrency and error recovery, earlier research showed that only syntactic obliviousness between the base program and aspects is possible. Our meta-model and framework follow an aspect-oriented approach focused on the object-oriented orthogonal persistent context. The proposed meta-model is characterized by its simplicity in order to achieve efficient and transparent database evolution mechanisms. Our meta-model supports multiple versions of a class structure by applying a class versioning strategy. Thus, enabling bidirectional application compatibility among versions of each class structure. That is to say, the database structure can be updated because earlier applications continue to work, as well as later applications that have only known the updated class structure. The specific characteristics of orthogonal persistent systems, as well as a metadata enrichment strategy within the application's source code, complete the inception of the meta-model and have motivated our research work. To test the feasibility of the approach, a prototype was developed. Our prototype is a framework that mediates the interaction between applications and the database, providing them with orthogonal persistence mechanisms. These mechanisms are introduced into applications as an {\it aspect} in the aspect-oriented sense. Objects do not require the extension of any super class, the implementation of an interface nor contain a particular annotation. Parametric type classes are also correctly handled by our framework. However, classes that belong to the programming environment must not be handled as versionable due to restrictions imposed by the Java Virtual Machine. Regarding concurrency support, the framework provides the applications with a multithreaded environment which supports database transactions and error recovery. The framework keeps applications oblivious to the database evolution problem, as well as persistence. Programmers can update the applications' class structure because the framework will produce a new version for it at the database metadata layer. Using our XML based pointcut/advice constructs, the framework's instance adaptation mechanism is extended, hence keeping the framework also oblivious to this problem. The potential developing gains provided by the prototype were benchmarked. In our case study, the results confirm that mechanisms' transparency has positive repercussions on the programmer's productivity, simplifying the entire evolution process at application and database levels. The meta-model itself also was benchmarked in terms of complexity and agility. Compared with other meta-models, it requires less meta-object modifications in each schema evolution step. Other types of tests were carried out in order to validate prototype and meta-model robustness. In order to perform these tests, we used an OO7 small size database due to its data model complexity. Since the developed prototype offers some features that were not observed in other known systems, performance benchmarks were not possible. However, the developed benchmark is now available to perform future performance comparisons with equivalent systems. In order to test our approach in a real world scenario, we developed a proof-of-concept application. This application was developed without any persistence mechanisms. Using our framework and minor changes applied to the application's source code, we added these mechanisms. Furthermore, we tested the application in a schema evolution scenario. This real world experience using our framework showed that applications remains oblivious to persistence and database evolution. In this case study, our framework proved to be a useful tool for programmers and database administrators. Performance issues and the single Java Virtual Machine concurrent model are the major limitations found in the framework.

Machine for visual inspection

The project was made during the Erasmus+ Program in Instituto Superior de Engenharia do Porto, Portugal. I had a pleasure to do this in Gislotica Mechanical Solution, Lda. This document presents a process of design a vertical inspection station for truck tires. The first part contains an introduction. There are information about Gislotica Company and also first analysis of problem. In next part is presented way to figured out the task and described all issues connected with designed machine. In last part were made some conclusions about problems and results. There is a place not only for sum up design process but also my develop during the project. I repeatedly pointed out which issues were new for me. A lot of times I focus on myself and gained experience and information about design process.

Tire inspection spreading machine

The aim of the project was to design in Solidworks and improve an existing Tire inspection machine. The project was developed in Gislotica - Mechanical Solutions, guided by ing. Rui Manuel Fazenda Silva who is a professor in ISEP. The designed device relates to the inspection of automobile tires for holes and weak places caused by punctures and usage. Such inspection includes careful examination of the inside surface of the tire which is difficult because of its cylindrical shape, stiff and resistant nature of the material out of which the tire is made. The whole idea is to provide a machine by which the walls of the tire may be spread and hold apart, presenting the inner surface for the worker to control. The device must also perform rotational and vertical movement of the tire. It is meant to provide inspection in hich there is no need for the controller to use force. It makes his work easier and more efficient.

Modélisation et analyse d'une machine à absorption/compression hybride fonctionnant à partir de rejets thermiques basse température

Les applications de réfrigération sont aujourd’hui majoritairement réalisées par des machines à compression alimentées en électricité. Animées à partir d’une source chaude, l’utilisation de machines à absorption permet d’utiliser très peu d’électricité comparée à une machine à compression et d’utiliser des réfrigérants écologiques. Le faible coefficient de performance et le coût élevé de ces machines est compensé par l’utilisation de rejets thermiques industriels destinés à être rejeté dans l’environnement et donc considérés comme gratuits. Le but de cette étude est de modéliser une machine à absorption hybride, utilisant le couple de fluide eau et ammoniac, en y ajoutant un compresseur ou booster dans la zone haute pression du circuit et d’évaluer ses performances. Cette modification crée une pression intermédiaire au désorbeur permettant de diminuer la température des rejets thermiques exploitables. Une température de rejets réutilisable de 50°C, contre 80°C actuellement, ouvrirait alors la voie à de nouvelles sources communes d’énergie. Le logiciel ASPEN Plus de simulation des procédés a été choisi afin de modéliser en régime permanent le système. Le modèle est en partie validé par l’étude expérimentale d’une machine à absorption commerciale de 10kW pour des applications de climatisation. Cette machine est située au Laboratoire des Technologies de l’Énergie d’Hydro-Québec. Ensuite, une étude de design permet de montrer, à puissance de réfrigération constante, les impacts bénéfiques de la technologie hybride sur le rendement exergétique, mais également sur la taille globale des échangeurs nécessaires. La technologie hybride est alors analysée économiquement face à une machine à absorption chauffée au gaz pour montrer sa rentabilité.