Applications of graph transformation in tools for domain-specific modeling languages

The use of domain-specific languages (DSLs) has been proposed as an approach to cost-e ectively develop families of software systems in a restricted application domain. Domain-specific languages in combination with the accumulated knowledge and experience of previous implementations, can in turn be used to generate new applications with unique sets of requirements. For this reason, DSLs are considered to be an important approach for software reuse. However, the toolset supporting a particular domain-specific language is also domain-specific and is per definition not reusable. Therefore, creating and maintaining a DSL requires additional resources that could be even larger than the savings associated with using them. As a solution, di erent tool frameworks have been proposed to simplify and reduce the cost of developments of DSLs. Developers of tool support for DSLs need to instantiate, customize or configure the framework for a particular DSL. There are di erent approaches for this. An approach is to use an application programming interface (API) and to extend the basic framework using an imperative programming language. An example of a tools which is based on this approach is Eclipse GEF. Another approach is to configure the framework using declarative languages that are independent of the underlying framework implementation. We believe this second approach can bring important benefits as this brings focus to specifying what should the tool be like instead of writing a program specifying how the tool achieves this functionality. In this thesis we explore this second approach. We use graph transformation as the basic approach to customize a domain-specific modeling (DSM) tool framework. The contributions of this thesis includes a comparison of di erent approaches for defining, representing and interchanging software modeling languages and models and a tool architecture for an open domain-specific modeling framework that e ciently integrates several model transformation components and visual editors. We also present several specific algorithms and tool components for DSM framework. These include an approach for graph query based on region operators and the star operator and an approach for reconciling models and diagrams after executing model transformation programs. We exemplify our approach with two case studies MICAS and EFCO. In these studies we show how our experimental modeling tool framework has been used to define tool environments for domain-specific languages.

Rigorous development of safety-critical systems

Nowadays, computer-based systems tend to become more complex and control increasingly critical functions affecting different areas of human activities. Failures of such systems might result in loss of human lives as well as significant damage to the environment. Therefore, their safety needs to be ensured. However, the development of safety-critical systems is not a trivial exercise. Hence, to preclude design faults and guarantee the desired behaviour, different industrial standards prescribe the use of rigorous techniques for development and verification of such systems. The more critical the system is, the more rigorous approach should be undertaken. To ensure safety of a critical computer-based system, satisfaction of the safety requirements imposed on this system should be demonstrated. This task involves a number of activities. In particular, a set of the safety requirements is usually derived by conducting various safety analysis techniques. Strong assurance that the system satisfies the safety requirements can be provided by formal methods, i.e., mathematically-based techniques. At the same time, the evidence that the system under consideration meets the imposed safety requirements might be demonstrated by constructing safety cases. However, the overall safety assurance process of critical computerbased systems remains insufficiently defined due to the following reasons. Firstly, there are semantic differences between safety requirements and formal models. Informally represented safety requirements should be translated into the underlying formal language to enable further veri cation. Secondly, the development of formal models of complex systems can be labour-intensive and time consuming. Thirdly, there are only a few well-defined methods for integration of formal verification results into safety cases. This thesis proposes an integrated approach to the rigorous development and verification of safety-critical systems that (1) facilitates elicitation of safety requirements and their incorporation into formal models, (2) simplifies formal modelling and verification by proposing specification and refinement patterns, and (3) assists in the construction of safety cases from the artefacts generated by formal reasoning. Our chosen formal framework is Event-B. It allows us to tackle the complexity of safety-critical systems as well as to structure safety requirements by applying abstraction and stepwise refinement. The Rodin platform, a tool supporting Event-B, assists in automatic model transformations and proof-based verification of the desired system properties. The proposed approach has been validated by several case studies from different application domains.

Net working capital estimation model in project business

The objective of this Master’s thesis is to develop a model which estimates net working capital (NWC) monthly in a year period. The study is conducted by a constructive research which uses a case study. The estimation model is designed in the need of one case company which operates in project business. Net working capital components should be linked together by an automatic model and estimated individually, including advanced components of NWC for example POC receivables. Net working capital estimation model of this study contains three parts: output template, input template and calculation model. The output template gets estimate values automatically from the input template and the calculation model. Into the input template estimate values of more stable NWC components are inputted manually. The calculate model gets estimate values for major affecting components automatically from the systems of a company by using a historical data and made plans. As a precondition for the functionality of the estimation calculation is that sales are estimated in one year period because the sales are linked to all NWC components.

Mittausvirtoihin liittyvä standardointi- ja kooditusehdotus uusilla energiamarkkinoilla

Sähkömarkkinaosapuolet ovat havainneet lukuisia puutteita ja haasteita tietojärjestelmien tiedonvaihtoon liittyvissä kysymyksissä. Tässä työssä käsitellään tiedonvaihdon ongelmaa mittausvirtojen kannalta. Tiedonvaihdon lisääntyminen ja sanomien monipuolistuminen on johtanut siihen, että läheskään kaikki tarpeelliset sanomat eivät ole standardoitu, ja jo luoduissa tai ehdotetuissa standardeissa on huomattavia eroavaisuuksia mm. eri maiden välillä. Tässä työssä kuvataan nykyinen automaattisen mittarinlukujärjestelmän ja jakeluverkkoyhtiön mittaustietovaraston välinen tiedonvaihtoratkaisu ja siihen liittyvät mittaustietovirrat. Työssä esitellään myös älykkäiden mittarien tuomia hyötyjä ja pohditaan uusien mittausten tuomia mahdollisuuksia. Lisäksi pohditaan nykyisten tietovirtojen koodituskäytäntöjen toimivuutta ja niiden puutteita ja ongelmia. Työssä laaditaan esimerkki standardi mittausvirtakonfiguraation mallintamiseksi sähkömarkkinoilla. Työn painopiste on energiamittaustietojen tietovirroissa lähtien laskutuksen tarpeista. Tavoitteena on automaattisten mittarinhallintaprojektien tuomien älykkäiden mittarien uusien mittausten aiheuttaman ja mahdollistaman tietovirran standardointi. Työssä pohditaan, kuinka tietovirta saadaan eheästi siirtymään mittauspalveluntarjoajan ja jakeluverkkoyhtiön järjestelmien välillä sekä miten uudet tiedonkäyttötarpeet tulisi koodittaa. Uudet sanomastandardiehdotukset esitetään XML-mallein, ja lopuksi pohditaan mallien toimivuutta ja niihin tarvittavia jatkokehitystarpeita.

Future revenue models: Transformation from textbooks to digital solutions in the educational publishing industry, Case Sanoma Learning

This study was conducted in order to learn how companies’ revenue models will be transformed due to the digitalisation of its products and processes. Because there is still only a limited number of researches focusing solely on revenue models, and particularly on the revenue model change caused by the changes at the business environment, the topic was initially approached through the business model concept, which organises the different value creating operations and resources at a company in order to create profitable revenue streams. This was used as the base for constructing the theoretical framework for this study, used to collect and analyse the information. The empirical section is based on a qualitative study approach and multiple-case analysis of companies operating in learning materials publishing industry. Their operations are compared with companies operating in other industries, which have undergone comparable transformation, in order to recognise either similarities or contrasts between the cases. The sources of evidence are a literature review to find the essential dimensions researched earlier, and interviews 29 of managers and executives at 17 organisations representing six industries. Based onto the earlier literature and the empirical findings of this study, the change of the revenue model is linked with the change of the other dimen-sions of the business model. When one dimension will be altered, as well the other should be adjusted accordingly. At the case companies the transformation is observed as the utilisation of several revenue models simultaneously and the revenue creation processes becoming more complex.

Marketing of fire suppression systems: customer value and institutional aspects

The paper studied marketing of automatic fire suppression systems from the perspectives of customer value and institutions. The object of the study was research the special features of the sales and marketing of fire suppression systems, and find some practical applications for sales, and for lobbying of a new fire suppression technology. The theoretical background of the study was in the customer value literature and the theoretical concept of institutional entrepreneurship. The research was conducted as an electronic survey for three different groups of respondents; end customers, solution integrators, and re-sellers. From the answers was gathered generalisations about the customer value assessment and communication of the value related to the sales and marketing processes of the fire suppression systems. In addition, there was observed manners to receive information about the systems, and effects caused by institutions to the decision making of the different parties involved. The findings of the study support companies that are launching a new safety technology to the market focus their marketing, and help to understand institutional forces that are affecting to a safety related product.

Computational models for and from biology : simple gene assembly and reaction systems

The advancement of science and technology makes it clear that no single perspective is any longer sufficient to describe the true nature of any phenomenon. That is why the interdisciplinary research is gaining more attention overtime. An excellent example of this type of research is natural computing which stands on the borderline between biology and computer science. The contribution of research done in natural computing is twofold: on one hand, it sheds light into how nature works and how it processes information and, on the other hand, it provides some guidelines on how to design bio-inspired technologies. The first direction in this thesis focuses on a nature-inspired process called gene assembly in ciliates. The second one studies reaction systems, as a modeling framework with its rationale built upon the biochemical interactions happening within a cell. The process of gene assembly in ciliates has attracted a lot of attention as a research topic in the past 15 years. Two main modelling frameworks have been initially proposed in the end of 1990s to capture ciliates’ gene assembly process, namely the intermolecular model and the intramolecular model. They were followed by other model proposals such as templatebased assembly and DNA rearrangement pathways recombination models. In this thesis we are interested in a variation of the intramolecular model called simple gene assembly model, which focuses on the simplest possible folds in the assembly process. We propose a new framework called directed overlap-inclusion (DOI) graphs to overcome the limitations that previously introduced models faced in capturing all the combinatorial details of the simple gene assembly process. We investigate a number of combinatorial properties of these graphs, including a necessary property in terms of forbidden induced subgraphs. We also introduce DOI graph-based rewriting rules that capture all the operations of the simple gene assembly model and prove that they are equivalent to the string-based formalization of the model. Reaction systems (RS) is another nature-inspired modeling framework that is studied in this thesis. Reaction systems’ rationale is based upon two main regulation mechanisms, facilitation and inhibition, which control the interactions between biochemical reactions. Reaction systems is a complementary modeling framework to traditional quantitative frameworks, focusing on explicit cause-effect relationships between reactions. The explicit formulation of facilitation and inhibition mechanisms behind reactions, as well as the focus on interactions between reactions (rather than dynamics of concentrations) makes their applicability potentially wide and useful beyond biological case studies. In this thesis, we construct a reaction system model corresponding to the heat shock response mechanism based on a novel concept of dominance graph that captures the competition on resources in the ODE model. We also introduce for RS various concepts inspired by biology, e.g., mass conservation, steady state, periodicity, etc., to do model checking of the reaction systems based models. We prove that the complexity of the decision problems related to these properties varies from P to NP- and coNP-complete to PSPACE-complete. We further focus on the mass conservation relation in an RS and introduce the conservation dependency graph to capture the relation between the species and also propose an algorithm to list the conserved sets of a given reaction system.

Yhtenäistetyn mallinnuskielen hyödyntäminen betoniaseman ohjausjärjestelmän kehityksessä

Yhtenäistetty mallinnuskieli, Unified Modeling Language (UML), on saavuttanut ohjelmistoteollisuudessa defacto standardin mallinnuskielen aseman. UML:n pääasiallinen käyttökohde on ollut ohjelmistojärjestelmien mallinnus, mutta sitä on sovellettu myös muillakin ongelma-alueilla, kuten erilaisten prosessien mallinnuksessa. Tässä diplomityössä mallinnetaan eräs betoniaseman ohjausjärjestelmä käyttäen UML:ää. Työssä perehdytään alan kirjallisuuden avulla siihen, miten teollisuus on hyödyntänyt UML:ää prosessien ohjausjärjestelmien mallinnuksessa. Kirjallisuudesta saatua tietoa sovelletaan betoniaseman ohjausjärjestelmän mallinnuksessa. Luotua mallia analysoidaan sen oikeellisuuden ja käytettävyyden perusteella. Työssä havaittiin, että UML soveltuu hyvin betoniaseman ohjausjärjestelmän kaltaisen teollisuusprosessin ohjauksen mallinnukseen. UML-mallilla voidaan kuvata järjestelmän rakenne ja toiminta kattavasti. Luotua mallia voidaan hyödyntää suoraan ohjausjärjestelmän jatkokehityksessä. Julkista tutkimustietoa aiheesta on kuitenkin niukasti saatavilla, joten lisätarve julkiselle tutkimukselle on olemassa.

Kattilalaitosten järjestelmällinen suunnittelu ja modulaarinen rakenne

Tämän diplomityön tavoitteena on tutkia kattilalaitosten järjestelmällistä suunnittelua, huomioiden laitoksen elinkaariprosessit ja modulaarinen tuoterakenne. Kattilalaitokset investointituotteina toteutetaan tyypillisesti projektitoimintamallilla, jolloin jokainen toimitus suunnitellaan alusta kyseisen kohteen vaatimusten perusteella. Päätöksenteon peruste on laitosasiakkaiden osalta tyypillisesti hinta, jonkavuoksi laitoksen perusratkaisut tulee olla ennalta määriteltyjä ja toimitusprosessi huolellisesti suunniteltu, jotta kustannukset ja aikataulu ovat ennustettavissa. Projektitoimituksissa projektipäälliköllä on merkittävä vastuu myös suunnittelun onnistumisesta ja käytössä olevat projektinhallintamallit ovat hyvin tuotekeskeisiä, jolloin vaatimuksia ei riittävästi huomioida ja siten toteutettu laitosratkaisu ei täytä usein sidosryhmien asettamia vaatimuksia. Monimutkaisten järjestelmien kehittämiseen ja suunnitteluun on olemassa Systems Engineering - suunnittelumalli, jonka hyödyntäminen energiatekniikan alalla on ollut vielä vähäistä. Malli tarjoaa yhdessä ISO/ICE 15288 standardin kanssa valmiit prosessit tuotteen järjestelmälliselle suunnittelulle. Modulaariset tuoterakenteet ovat olleet perusvaatimus komponenttien toimitusten osalta, mutta laitosjärjestelmien tuotteistaminen on koettu vaikeaksi runsaan räätälöintitarpeen takia. Prosessimaisella toimintamallilla voidaan tuottaa modulaarisia tuoterakenteita ja tehostaa kattilalaitosten muutosten hallintaa. Tutkimuksessa tunnistettiin tyypilliset kattilalaitoksen suunnittelun prosessit kattilalaitosten kokonaistoimituksiin erikoistuneelle KPA Unicon Oy:lle.

Production Cycle Optimization: Defining the Market Potential for a New Planning Tool

An optimization tool has been developed to help companies to optimize their production cycles and thus improve their overall supply chain management processes. The application combines the functionality that traditional APS (Advanced Planning System) and ARP (Automatic Replenishment Program) systems provide into one optimization run. A qualitative study was organized to investigate opportunities to expand the product’s market base. Twelve personal interviews were conducted and the results were collected in industry specific production planning analyses. Five process industries were analyzed to identify the product’s suitability to each industry sector and the most important product development areas. Based on the research the paper and the plastic film industries remain the most potential industry sectors at this point. To be successful in other industry sectors some product enhancements would be required, including capabilities to optimize multiple sequential and parallel production cycles, handle sequencing of complex finishing operations and to include master planning capabilities to support overall supply chain optimization. In product sales and marketing processes the key to success is to find and reach the people who are involved directly with the problems that the optimization tool can help to solve.

Keskitehoestimaattorin lisääminen diesel-sähköiseen hybridijärjestelmään

Nykyajan jatkuvasti kiristyvät päästörajoitukset ja ilmastonmuutoksen uhka ovat ajavia voimia kehittämään voimalaitosten tekniikkaa energiatehokkaampaan ja ympäristöystävällisempään suuntaan. Polttomoottoritekniikan parantaminen on tärkeä osa tätä kehitystä, mutta jo nykyisiä moottoreita voitaisiin ajaa energiate-hokkaammin käyttämällä akustoa ja älykästä säätöjärjestelmää apuna. Työssä tutkitaan simulaatioiden avulla voidaanko ulkomerellä toimivan huolto-aluksen energiatehokkuutta parantaa muokkaamalla sen tehon tuottoa keskitehoes-timaattorin ja akuston avulla.

Laadunhallintajärjestelmäprojektin suunnittelu ja projektiorganisaation toimintatapojen kartoittaminen

Tämän diplomityön tavoitteina oli luoda suunnitelma ISO 9001 ja 14001 -sertifikaatteihin oikeuttavalle laadunhallintajärjestelmälle ja luoda malli projektiorganisaation toiminnan mittaamiselle ja kehittämiselle. Lisäksi työn tarkoituksena oli luoda teoreettinen osaamispohja projektipäällikölle laadunhallintajärjestelmäprojektin läpiviemisen tueksi. Työssä perehdyttiin laadunhallinnan periaatteisiin, tietojärjestelmäprojektikehityksen elinkaareen, tietojärjestelmäprojektien kriittisiin menestystekijöihin ja itsearviointimallin laatimisperiaatteisiin. Diplomityön kanssa lomittain suoritetulle laadunhallintajärjestelmäprojektille parhaiten sopivat käytännöt tunnistettiin kirjallisuudesta sekä puolistrukturoidulla haastattelulla Volvo Finland Ab:n johdon edustajille. Työssä luodun suunnitelman mukainen laadunhallintajärjestelmä toteutettiin Volvo Finland Ab:lle yhdessä nelikymmenhenkisen projektiorganisaation kanssa. Projektin aikana tehdyn aktiivisen, osallistuvan havainnoinnin ja diplomityössä luodun itsearviointimallin perusteella kartoitettiin projektiorganisaatiolle parhaiten sopivat toimintamenetelmät. Toimintamenetelmäkartoituksen tuloksena todettiin, että organisaation tietotaito on vertikaalista ja tästä syystä resurssienhallinta nostettiin kriittisimmäksi elementiksi projektien onnistumisen kannalta. Resurssienhallinnan tueksi ehdotettiin Stage-Gate-mallia projektien läpiviemiseen. Mallin avulla voitaisiin resurssit hallitusti kohdistaa uudelleen projektin joka vaiheessa.

Non-Linear Journal Bearing Model for Analysis of Superharmonic Vibrations of Rotor Systems

A rotating machine usually consists of a rotor and bearings that supports it. The nonidealities in these components may excite vibration of the rotating system. The uncontrolled vibrations may lead to excessive wearing of the components of the rotating machine or reduce the process quality. Vibrations may be harmful even when amplitudes are seemingly low, as is usually the case in superharmonic vibration that takes place below the first critical speed of the rotating machine. Superharmonic vibration is excited when the rotational velocity of the machine is a fraction of the natural frequency of the system. In such a situation, a part of the machine’s rotational energy is transformed into vibration energy. The amount of vibration energy should be minimised in the design of rotating machines. The superharmonic vibration phenomena can be studied by analysing the coupled rotor-bearing system employing a multibody simulation approach. This research is focused on the modelling of hydrodynamic journal bearings and rotorbearing systems supported by journal bearings. In particular, the non-idealities affecting the rotor-bearing system and their effect on the superharmonic vibration of the rotating system are analysed. A comparison of computationally efficient journal bearing models is carried out in order to validate one model for further development. The selected bearing model is improved in order to take the waviness of the shaft journal into account. The improved model is implemented and analyzed in a multibody simulation code. A rotor-bearing system that consists of a flexible tube roll, two journal bearings and a supporting structure is analysed employing the multibody simulation technique. The modelled non-idealities are the shell thickness variation in the tube roll and the waviness of the shaft journal in the bearing assembly. Both modelled non-idealities may cause subharmonic resonance in the system. In multibody simulation, the coupled effect of the non-idealities can be captured in the analysis. Additionally one non-ideality is presented that does not excite the vibrations itself but affects the response of the rotorbearing system, namely the waviness of the bearing bushing which is the non-rotating part of the bearing system. The modelled system is verified with measurements performed on a test rig. In the measurements the waviness of bearing bushing was not measured and therefore it’s affect on the response was not verified. In conclusion, the selected modelling approach is an appropriate method when analysing the response of the rotor-bearing system. When comparing the simulated results to the measured ones, the overall agreement between the results is concluded to be good.

AMB system for high-speed motors using automatic commissioning

The general trend towards increasing e ciency and energy density drives the industry to high-speed technologies. Active Magnetic Bearings (AMBs) are one of the technologies that allow contactless support of a rotating body. Theoretically, there are no limitations on the rotational speed. The absence of friction, low maintenance cost, micrometer precision, and programmable sti ness have made AMBs a viable choice for highdemanding applications. Along with the advances in power electronics, such as signi cantly improved reliability and cost, AMB systems have gained a wide adoption in the industry. The AMB system is a complex, open-loop unstable system with multiple inputs and outputs. For normal operation, such a system requires a feedback control. To meet the high demands for performance and robustness, model-based control techniques should be applied. These techniques require an accurate plant model description and uncertainty estimations. The advanced control methods require more e ort at the commissioning stage. In this work, a methodology is developed for an automatic commissioning of a subcritical, rigid gas blower machine. The commissioning process includes open-loop tuning of separate parts such as sensors and actuators. The next step is to apply a system identi cation procedure to obtain a model for the controller synthesis. Finally, a robust model-based controller is synthesized and experimentally evaluated in the full operating range of the system. The commissioning procedure is developed by applying only the system components available and a priori knowledge without any additional hardware. Thus, the work provides an intelligent system with a self-diagnostics feature and an automatic commissioning.

Lectio praecursoria : Systems between information and knowledge : in a memory management model of an extended enterprise

VTT Jouni Meriluodon valtio-opin alaan kuuluva väitöskirja Systems between information and knowledge : in a memory management model of an extended enterprise tarkastettiin 21.6.2011 Helsingin yliopistossa.