Clock constraint specification language: specifying clock constraints with UML/MARTE

The Object Management Group (OMG) unified modeling language (UML) profile for modeling and analysis of real-time and embedded systems (MARTE) aims at using the general-purpose modeling language UML in the domain of real-time and embedded (RTE) systems. To achieve this goal, it is absolutely required to introduce inside the mainly untimed UML an unambiguous time structure which MARTE model elements can rely on to build precise models amenable to formal analysis. The MARTE Time model has defined such a structure. We have also defined a non-normative concrete syntax called the clock constraint specification language (CCSL) to demonstrate what can be done based on this structure. This paper gives a brief overview of this syntax and its formal semantics, and shows how existing UML model elements can be used to apply this syntax in a graphical way and benefit from the semantics.     

A family of languages for architecture constraint specification

During software development, architecture decisions should be documented so that quality attributes guaranteed by these decisions and required in the software specification could be persisted. An important part of these architectural decisions is often formalized using constraint languages which differ from one stage to another in the development process. In this paper, we present a family of architectural constraint languages, called ACL. Each member of this family, called a profile, can be used to formalize architectural decisions at a given stage of the development process. An ACL profile is composed of a core constraint language, which is shared with the other profiles, and a MOF architecture metamodel. In addition to this family of languages, this paper introduces a transformation-based interpretation method of profiles and its associated tool.     

A modular timed graph transformation language for simulation-based design

We introduce the MoTif (Modular Timed graph transformation) language, which allows one to elegantly model complex control structures for programmed graph transformation. These include modular construction, parallel composition, and a temporal dimension in addition to the usual transformation control structures. The first part of this contribution formally introduces MoTif and its semantics is based on the Discrete EVent system Specification (DEVS) formalism which allows for highly modular, hierarchical modelling of timed, reactive systems. In MoTif, graphs are embedded in events and individual transformation rules are embedded in atomic DEVS models. A side effect of the use of DEVS is the introduction of an explicit notion of time. This allows one to model a time-advance for every rule as well as to interrupt (pre-empt) rule execution. In the second part, we design a case study to show how the explicit notion of time allows for the simulation-based design of reactive systems such as modern computer games. We use the well-known game of PacMan as an example and model its dynamics in MoTif. This also allows the modelling of player behaviour, incorporating data about human players’ behaviour, and reaction times. Thus, a model of both player and game is obtained which can be used to evaluate, through simulation, the playability of a game design. We propose a playability performance measure and change the value of some parameters of the PacMan game. For each variant of the game thus obtained, simulation yields a value for the quality of the game. This allows us to choose an “optimal” (from a playability point of view) game configuration. The user model is subsequently replaced by a visual interface to a real player, and the game model is executed using a real-time DEVS simulator.     

LanguageCrawl: a generic tool for building language models upon common Crawl

The exponential growth of the internet community has resulted in the production of a vast amount of unstructured data, including web pages, blogs and social media. Such a volume consisting of hundreds of billions of words is unlikely to be analyzed by humans. In this work we introduce the tool LanguageCrawl, which allows Natural Language Processing (NLP) researchers to easily build web-scale corpora using the Common Crawl Archive—an open repository of web crawl information, which contains petabytes of data. We present three use cases in the course of this work: filtering of Polish websites, the construction of n-gram corpora and the training of a continuous skipgram language model with hierarchical softmax. Each of them has been implemented within the LanguageCrawl toolkit, with the possibility to adjust specified language and n-gram ranks. This paper focuses particularly on high computing efficiency by applying highly concurrent multitasking. Our tool utilizes effective libraries and design. LanguageCrawl has been made publicly available to enrich the current set of NLP resources. We strongly believe that our work will facilitate further NLP research, especially in under-resourced languages, in which the lack of appropriately-sized corpora is a serious hindrance to applying data-intensive methods, such as deep neural networks.

     

A specification language for organisational performance indicators

A specification language for performance indicators and their relations and requirements is presented and illustrated for a case study in logistics. The language can be used in different forms, varying from informal, semiformal, graphical to formal. A software environment has been developed that supports the specification process and can be used to automatically check whether performance indicators or relations between them or certain requirements over them are satisfied in a given organisational process. This paper is an extended version of the paper which appeared in: M. Ali and F. Esposito, editors, Proceedings of 18th International Conference on Industrial & Engineering Applications of Artificial Intelligence & Expert Systems, IEA/AIE 2005, vol. 3533 of Lecture Notes in Artificial Intelligence, pp. 667–677, Springer Verlag, 2005.     

Attribute specification for finite element models

Two different approaches for the application of problem specific attributes to finite element models are discussed. In both approaches interactive computer graphics techniques and the use of a top-down program approach is emphasized. The major difference in the approaches is the point during problem definition that the attributes are applied and manifests itself primarily in the program's database with little effect on program operation. Program operation is demonstrated through the use of an example problem. Finally, the advantages and disadvantages of the two approaches are discussed.     

A development environment for an object specification language

Techniques for the development of reliable information systems on the basis of their formal specification are the main concern in the project. Our work focuses on the specification language TROLL light which allows one to describe the part of the world to be modeled as a community of concurrently existing and communicating objects. Our specification language comes with an integrated, open development environment. The task of this environment is to give support for the creation of correct information systems. Two important ingredients of the environment are the animator and the proof support system     

Modechart: a specification language for real-time systems

Present a specification language for real-time systems called Modechart. The semantics of Modechart is given in terms of real-time logic (RTL), which is especially amenable to reasoning about the absolute (real-time clock) timing of events. The semantics of Modechart has an important property that the translation of a Modechart specification into RTL formulas results in a hierarchical organization of the resulting RTL assertions. This gives us significant leverage in reasoning about properties of a system by allowing us to filter out assertions that concern lower levels of abstraction. Some results about desirable properties of Modechart specifications are given. A graphical implementation of Modechart has been completed     

Control specification language for distributed computation in mis

Some principles of on-line computation in a distributed computing environment are proposed. These principles are based on a semantic superstructure over a labeled multigraph, intended for formalized representation of MIS distributed information technologies.Translated from Kibernetika, No. 4, pp. 40–44, July–August, 1990.     

Spectra: a specification language for reactive systems

We introduce Spectra, a new specification language for reactive systems, specifically tailored for the context of reactive synthesis. The meaning of Spectra is defined by a translation to a kernel language. Spectra comes with the Spectra Tools, a set of analyses, including a synthesizer to obtain a correct-by-construction implementation, several means for executing the resulting controller, and additional analyses aimed at helping engineers write higher-quality specifications. We present the language in detail and give an overview of its tool set. Together with the language and its tool set, we present four collections of many, non-trivial, large specifications, written by undergraduate computer science students for the development of autonomous Lego robots and additional example reactive systems. The collected specifications can serve as benchmarks for future studies on reactive synthesis. We present the specifications, with observations and lessons learned about the potential use of reactive synthesis by software engineers.

     

A familial specification language for database application systems

The Familial Specification Language is a set theoretic and functional language providing a unified approach to the less-procedural design of database application systems. The language is proposed to be both a database language and an application program specification language. The unique data structure employed, the family of sets, provides the designer with a unified framework, both to model and maintain data, and to algebraically specify the application programs without looping or branching, and with no side effects. Using the same data structure in both the data model and the problem specification creates a natural interface between the database and the application programs. Special emphasis is placed on aggregation and classification, the major problems is business data processing.     

The NDB database specified in the RAISE specification language

This paper answers a challenge designed to test the modularization features of specification languages. The RAISE Specification Language (RSL) is shown to have the power necessary to meet the challenge.Basic features of RSL, particularly those useful for the problem, are introduced. Two solutions to the problem are exhibited. The first follows the structure of the challenge problem very closely and is model-based in style. The second shows how RSL may be written in an algebraic style.An example of a proof of implementation is also given.     

A practical approach for testing timed deterministic finite state machines with single clock

Finite State Machines (FSMs) are widely used for verification and testing of many reactive systems and many methods are proposed for generating tests from FSMs with the guaranteed fault coverage. However, some systems can only be properly described when time constraints are considered, advocating the adoption of models with the notion of time. In this paper, a method for deriving conformance tests with the guaranteed fault coverage from a Timed FSM (TFSM) with a single clock is presented. Test derivation is based on a given fault domain that allows the derivation of test suites with reasonable length. More precisely, the fault domain includes every possible faulty TFSM implementation with the known largest time constraints boundaries and minimal duration of time guards. Given a deterministic possibly partial TFSM specification, a complete test suite that guarantees the detection of all faulty implementations with respect to the above fault domain is derived. Experiments with randomly generated timed FSMs are conducted to determine length of obtained test suites and assess the impact of varying the TFSM specification parameters on length of obtained test suites. Further, experiments with both untimed and timed machines are conducted and these experiments show that similar patterns for timed and untimed machines are obtained with respect to varying the number of states, inputs, and outputs of machines.     

H: A component-based specification language for heterogeneous applications

This paper presents H, a minimalistic specification language for designing heterogeneous software applications, particularly in the realms of robotics and industria, which takes advantage of a Component-Based Software Engineering (CBSE) approach. H copes with some of the most outstanding characteristics of these systems, like diversity at different levels (hardware platforms, programming languages, programmer skills), network distribution, real time and fault-tolerance. The H specification covers the life-cycle of any heterogeneous application. Its development system offers to the designer and/or builder a set of tools for specifying modules, generating code semiautomatically, debugging, maintenance, and a real time analysis of the system.     

A specification language for the processing of technical-economic indicators

The paper describes a specification language for the processing of records with technical—economic content in distributed control systems. The principles of the specification language are close to logic languages and to data-structure oriented languages. The language has been implemented on a computer system.Translated from Kibernetika i Sistemnyi Analiz, No. 4, pp. 152–164, 179, July–august, 1991.     

SWSL: a synthetic workload specification language for real-timesystems

We discuss the issues that must be addressed in the specification and generation of synthetic workloads for distributed real-time systems. We describe a synthetic workload specification language (SWSL) that defines a workload in a form that can be compiled by a synthetic workload generator (SWG) to produce an executable synthetic workload. The synthetic workload is then downloaded to the target machine and executed while performance and dependability measurements are made. SWSL defines the workload at the task level using a data flow graph, and at the operation level using control constructs and synthetic operations taken from a library. It is intended to be easy to use, flexible, and capable of creating synthetic workloads that are representative of real-time workloads. It provides a compact, parameterized notation. It supports automatic replication of objects to facilitate the specification of large workloads for distributed real-time systems. It also provides extensive support for the experimentation process     

Moduli-based language for building problem-solving scenarios

We propose a language for executive specification of problem-solving scenarios. The scenarios are an aggregate of actions realized as independent software moduli, the information connections between them and the sequence of their execution. An executive system controlling the execution of the scenarios was developed on the basis of the language. This system is the kernel of a system for automated control system design. The scenarios have a hierarchical structure. The organization of the scenarios is based on an object-oriented paradigm. Every module is an instance of a particular type module, called class. This allows one and the same module to be executed in different contexts. A unique information interaction mechanism between the moduli in the scenarios, allowing on-line changes in the information flow, was developed. The language is problem-independent, and can be used in various problem domains.     

Topological analysis of 3D building models using a spatial query language

The paper presents parts of the development of a spatial query language for building information models. Such a query language enables the spatial analysis of building information models and the extraction of partial models that fulfill certain spatial constraints. Among other features, it includes topological operators, i.e. operators that reflect the topological relationships between 3D spatial objects. The paper presents definitions of the semantics of the topological operators within, contain, touch, overlap, disjoint and equal in 3D space by using the 9-intersection model. It further describes a possible implementation of the topological operators by means of an octree-based algorithm. The recursive algorithm presented in this article relies on a breadth-first traversal of the operands’ octree representations and the application of rules that are based on the color of the octants under examination. Because it successively increases the discrete resolution of the spatial objects employed, the algorithm enables the user on the one hand to handle topological relationships in a fuzzy manner and on the other hand to trade-off between computational effort and the required accuracy. The article also presents detailed investigations on the runtime performance of the developed algorithm.     

Building meaningful timed models of closed-loop DES for verification purposes

Formal verification methods require that a model of the system to analyze, in the form of a network of automata for instance, be built previously. Every evolution of this formal model must represent a real evolution of the modeled system; if the model contains indeed spurious evolutions, meaningless states, which do not correspond to physically possible states, can be reached and the verification results are surely not trustworthy. This paper focuses on construction of the formal model of a closed-loop system which can be represented as a Discrete Event System (DES) and where all evolutions and states are meaningful w.r.t. to the real system behavior. A closed-loop system is composed of a physical system to control, named plant, and a controller. A modular approach to build the plant model is presented in the first part of the paper; to prevent from meaningless evolutions and states in this model, a solution based on the concept of urgent edges is proposed and exemplified. Then, construction of the formal model of the closed-loop system is addressed; it is shown that restriction of the evolutions of this model to the only meaningful ones can be easily achieved by introducing variables that represent the modification of the inputs of the logic controller and the stability condition of the control specification.