Using domain specific languages to capture design knowledge for model-based systems engineering

Design synthesis is a fundamental engineering task that involves the creation of structure from a desired functional specification; it involves both creating a system topology as well as sizing the system's components. Although the use of computer tools is common throughout the design process, design synthesis is often a task left to the designer. At the synthesis stage of the design process, designers have an extensive choice of design alternatives that need to be considered and evaluated. Designers can benefit from computational synthesis methods in the creative phase of the design process. Recent increases in computational power allow automated synthesis methods for rapidly generating a large number of design solutions. Combining an automated synthesis method with an evaluation framework allows for a more thorough exploration of the design space as well as for a reduction of the time and cost needed to design a system. To facilitate computational synthesis, knowledge about feasible system configurations must be captured. Since it is difficult to capture such synthesis knowledge about any possible system, a design domain must be chosen. In this thesis, the design domain is hydraulic systems. In this thesis, Model-Driven Software Development concepts are leveraged to create a framework to automate the synthesis of hydraulic systems will be presented and demonstrated. This includes the presentation of a domain specific language to describe the function and structure of hydraulic systems as well as a framework for synthesizing hydraulic systems using graph grammars to generate system topologies. Also, a method using graph grammars for generating analysis models from the described structural system representations is presented. This approach fits in the context of Model-Based Systems Engineering where a variety of formal models are used to represent knowledge about a system. It uses the Systems Modeling Language developed by The Object Management Group (OMG SysML™) as a unifying language for model definition.M.S.Committee Chair: Paredis, Chris; Committee Member: McGinnis, Leon; Committee Member: Schaefer, Dir

The State of the Art in Language Workbenches. Conclusions from the Language Workbench Challenge

Language workbenches are tools that provide high-level mechanisms for the implementation of (domain-specific) languages. Language workbenches are an active area of research that also receives many contributions from industry. To compare and discuss existing language workbenches, the annual Language Workbench Challenge was launched in 2011. Each year, participants are challenged to realize a given domain-specific language with their workbenches as a basis for discussion and comparison. In this paper, we describe the state of the art of language workbenches as observed in the previous editions of the Language Workbench Challenge. In particular, we capture the design space of language workbenches in a feature model and show where in this design space the participants of the 2013 Language Workbench Challenge reside. We compare these workbenches based on a DSL for questionnaires that was realized in all workbenches

Electricity Consumption and Efficiency Trends in European Union - Status Report 2009

This report summarises the outcome of the results of an in-depth survey of electricity consumption in buildings in the EU-27 conducted by the JRC, the main findings of the first preparatory studies for implementing the Eco-design Directive, as well as other recent analyses and studies on different aspects of the electricity final consumption in EU27. One of the aims of this report is to show the present status of electricity consumption of the main appliances and equipment, the energy efficiency progress and estimates of the saving potential in the EU-27 electricity sector. The report summarises the policy actions introduced at EU level and some of the national policies for the building sector and for the electric motor systems.JRC.F.8-Renewable Energy (Ispra

Automated testing of Hypermedia REST applications

Testimine on oluline osa tarkvaraarenduse elutsüklis ja testidel põhinev arendamine on üks peamistest praktikatest Agile metoodikas. Tihti keskenduvad programmeerijad RESTful rakenduse loomise protsessis äriloogika testimisele ja unustavad kontrollida protokolli, mis teostab REST interaktsioone. Selles kontekstis pakutakse välja tööriist, mis automatiseerib testide genereerimist ja teostab interaktsioone RESTful rakendusega. Tööriist võtab sisendiks kasutuslood, mis on koostatud Gherkini kitsendatud versiooniga. See on domeenispetsiifiline keel käitumispõhiseks arenduseks. Kasutuslood, mis on kirjutatud selles Gherkini variandis, hõlmavad REST rakenduse poolt nõutud interaktsioone sellisel viisil, et neist on võimalik genereerida teste. Veelgi enam, tööriist genereerib samalt kasutusloolt täisfunktsionaalse pseudoteostuse.\n\rProgrammeerijad saavad kasutada neid pseudoteostusi kliendipoole arendamiseks, vajamata REST rakenduse tegelikku teostust. Käesolev töö tutvustab tööriista kasutust ja disainiprintsiipe ning esitab näite selle kasutamisest.Testing is one essential part of the software development lifecycle and Test Driven Development is one of the main practices in agile methodology. During the development of a RESTful web application, developers oftentimes focus only in testing the business logic and neglect testing the protocol implementing REST interactions. In this context, we propose a tool to automate the generation of test cases that exercise the interactions required by a RESTful application. The tool takes as input user stories written in restricted version of Gherkin, a widely use domain specific language for behaviour driven development. User stories written in this variant of Gherkin capture the essence of the interactions required by a REST application in a way that it is possible to derive test cases from them. Moreover, the tool derives fully functional mock implementations from the same input user story. Such mock implementations can be then used by programmers to develop the client side without requiring the actual implementation of the REST application. This document introduces the design principles and implementation of the tool and presents a study case showcasing its use

The environmental impacts of upgrading the Olushandja Dam, northern Namibia

Includes bibliographical references.The purpose of this dissertation is to assess and evaluate various water level management options for the upgrading of Olushandja Dam in northern Namibia within the framework of the environmental impact assessment carried out for the project. This will enable the Namibian Department of Water Affairs (DWA) to improve their management of the dam for the benefit of the local communities and consumers in the Oshana Water Region (Figure 5 . 1). The dam has been in existence since 1975 and is part of the Calueque-Olushandja inter-basin water transfer scheme. A pipeline and a series of canals links Calueque Dam , on the Cunene River in Angola , with Olushandja Dam in Namibia and the urban areas to the east and south. In order to provide for the expected increase in water requirements from agricultural and rural development the scheme is presently being upgraded. An environmental impact assessment (EIA) was initiated in 1994 by the DWA as a requirement of the Dutch Government who are funding the project. Biophysical studies were undertaken by staff from the DWA and private consultants from Windhoek. The socio-economic study was carried out by a study team from the Department of Environmental and Geographical Science, University of Cape Town, in association with a consultant from the University's Environmental Evaluation Unit (EEU). The EEU was appointed to compile a full EIA based on the findings of the specialist reports. This report is expected to be completed by October 1995

Analysis of supercritical carbon dioxide Brayton cycles for a helium-cooled pebble bed blanket DEMO-like fusion power plant

Article number 112860Nuclear fusion is expected to be a clean and almost-unlimited power source in the near future. The first net power demonstration plant (DEMO) is planned to start operation in 2050. The supercritical carbon dioxide (S-CO2) Brayton cycle is an excellent candidate for integration with a fusion power plant, such as DEMO, because of its high efficiency at intermediate temperatures and low interaction of coolant with tritium. This work analyses a set of S-CO2 Brayton cycle layouts for its integration in a DEMO-like fusion power plant, considering the specific requirements and heat availability characteristics. A framework has been developed to integrate the PROCESS code and the numerical solver EES to study the thermal and economic aspects of integrating the different S-CO2 cycle layouts. In total, 14 layouts have been studied and grouped into a more conservative (DEMO1, pulsed operation) and more advanced (DEMO2, steady-state operation) fusion reactors. The PROCESS code has been used to obtain the DEMO 2018 Baseline, which defines the available power from each heat source and their boundary conditions. This code has also been used to assess the cost of the optimal layout. Thermal storage has been added to the DEMO1 scenario to avoid standby times that could negatively affect the cycle equipment lifetime and efficiency. Besides, these boundary conditions have been extended to account for possible technical improvements by the time of its construction in the DEMO2 scenario. A sensitivity analysis of the most characteristic parameters of the cycles shows a strong dependence on the turbine inlet temperature for all layouts, which is constrained by the reactor material limits. The cycle efficiency (electric power produced before consumptions non-related to the cycle) has been selected as the figure of merit for the optimisation. The results show a 38% cycle efficiency for DEMO1 and 56% for DEMO2 scenarios. These efficiencies drop to 20% and 38% values, respectively, when the reactor and cooling loop power consumptions are considered. These values are obtained for current fusion reactor conceptual designs. The economic analysis shows the economic viability of DEMO2 scenarios.Ministerio de Ciencia e Innovación (España) FPU17/06273Horizonte 2020 (Unión Europea) 708257Horizonte 2020 (Unión Europea) 80516

Techno-economic Assessment of Optimised Vacuum Swing Adsorption for Post-Combustion CO2 capture from Steam-Methane Reformer Flue Gas

This study focuses on the techno-economic assessment integrated with detailed optimisation of a four step vacuum swing adsorption (VSA) process for post-combustion CO2 capture and storage (CCS) from steam-methane reformer dried flue gas containing 20 mol% CO2. The comprehensive techno-economic optimisation model developed herein takes into account VSA process model, peripheral component models, vacuum pump performance, scale-up, process scheduling and a thorough cost model. Three adsorbents, namely, Zeolite 13X (current benchmark material for CO2 capture) and two metal–organic frameworks, UTSA-16 (widely studied metal–organic framework for CO2 capture) and IISERP MOF2 (good performer in recent findings) are optimised to minimise the CO2 capture cost. Monoethanolamine (MEA)-based absorption technology serves as a baseline case to assess and compare optimal techno-economic performances of VSA technology for three adsorbents. The results show that the four step VSA process with IISERP MOF2 outperforms other two adsorbents with a lowest CO2 capture cost (including flue gas pre-treatment) of 33.6 € per tonne of CO2 avoided and an associated CO2 avoided cost of 73.0 € per tonne of CO2 avoided. Zeolite 13X and UTSA-16 resulted in CO2 avoided costs of 90.9 and 104.9 € per tonne of CO2 avoided, respectively. The CO2 avoided costs obtained for the VSA technology remain higher than that of the baseline MEA-based absorption process which was found to be 66.6 € per tonne of CO2 avoided. The study also demonstrates the importance of using cost as means of evaluating the separation technique compared to the use of process performance indicators. Accounting for the efficiency of vacuum pumps and the cost of novel materials such as metal–organic frameworks is highlighted. © 2020 Elsevier B.V.acceptedVersio