Graphical Modeling Environment Research Articles

An example is worth a thousand words: Creating graphical modelling environments by example

Domain-specific languages (DSLs) are heavily used in model-driven and end-user development approaches. Compared to general-purpose languages, DSLs present numerous benefits like powerful domain-specific primitives, an intuitive syntax for domain experts, and the possibility of advanced code generation for narrow domains. While a graphical syntax is sometimes desired for a DSL, constructing graphical modelling environments is a costly and highly technical task. This relegates domain experts to a rather passive role in their development and hinders a wider adoption of graphical DSLs. Our aim is achieving a simpler DSL construction process where domain experts can contribute actively. For this purpose, we propose an example-based technique for the automatic generation of modelling environments for graphical DSLs. This way, starting from examples of the DSL likely provided by domain experts using drawing tools like yED, our system synthesizes a graphical modelling environment that mimics the syntax of the provided examples. This includes a meta-model for the abstract syntax of the DSL and a graphical concrete syntax supporting spatial relationships like containment and adjacency. Our system, called metaBUP, is implemented as an Eclipse plug-in. In this paper, we demonstrate its usage on a running example in the home networking domain and evaluate its suitability for the construction of graphical modelling environments by means of a user study.

Automatic Layout of Scilab/Xcos Diagrams

Scilab/Xcos is a graphical modeling and simulation environment for hybrid dynamic systems. It provides a graphical editor which allows representing models with block diagrams. While each block represents a computational function, links specify the data and event flow. However, as the number of the blocks and the links increases, the Xcos schema can quickly become messy and difficult to read. In this paper, we present an approach for automatically updating the layout of an Xcos schema by manipulating the links and the split blocks, so that the diagrams can be kept well-presented and readable. In this approach, we update the link styles with an optimal route and then, rearrange the positions of blocks. The proposed approach is exemplified with sample Xcos models. In addition to providing the automatic layout capability to the Scilab/Xcos user, an application programming interface is also specified for the Scilab/Xcos developer who want to further enhance the provided feature set.

A proposed novel enterprise cloud development application model

Currently, there is limited guidance on generic cloud software architecture model for designing and building cloud applications and each platform provider has different standards that influences the way applications are developed and written. In this paper we propose a cloud application development model based on developing services (typically REST API services). We see clear benefits in applying this model to service oriented architecture (SOA) and business process management (BPM) design in order to develop enterprise applications for cloud environments in a systematic, rapid manner. This conceptual model described in this paper is drawn from the core ideas and practices behind REST API, BPM, and SOA. In this paper we focus on the proposed software development model for enterprise cloud applications and services. Throughout this paper we use the term cloud application and cloud service interchangeably. The model described in this paper can be applied to both. Further research on a software-modeling tool that provides a standardized structure for cloud software development and deployment seems to be in order. Supported by a graphical modeling environment, such a tool would utilize a Cloud Resource Provisioning language, will be able to seamlessly deploy and provision cloud resources across multiple cloud service providers. The presented research provides a practical and extensible application development model for cloud platforms. The model described can be used in a variety of applications as well as migration of legacy code to cloud platforms. By using this model, a cloud application can be deployed as small functionally separate components to different cloud nodes. Resource allocation can be defined for these nodes on a per need basis, which minimizes the cost of acquiring a fail over and load balanced system compared to the traditional on premise application development. In this paper, a detailed description of the analysis and development steps of the proposed model is also presented.

Intra- and interdiagram consistency checking of behavioral multiview models

Multiview modeling languages like UML are a very powerful tool to deal with the ever increasing complexity of modern software systems. By splitting the description of a system into different views—the diagrams in the case of UML—system properties relevant for a certain development activity are highlighted while other properties are hidden. This multiview approach has many advantages for the human modeler, but at the same time it is very susceptible to various kinds of defects that may be introduced during the development process. Besides defects which relate only to one view, it can also happen that two different views, which are correct if considered independently, contain inconsistent information when combined. Such inconsistencies between different views usually indicate a defect in the model and can be critical if they propagate up to the executable system.In this paper, we present an approach to formally verify the reachability of a global state of a set of communicating UML state machines, i.e., we present a solution for an intradiagram consistency checking problem. We then extend this approach to solve an interdiagram consistency checking problem. In particular, we verify whether the message exchange modeled in a UML sequence diagram conforms to a set of communicating state machines.For solving both kinds of problems, we proceed as follows. As a first step, we formalize the semantics of UML state machines and of UML sequence diagrams. In the second step, we build upon this formal semantics and encode both verification tasks as decision problems of propositional logic (SAT) allowing the use of efficient SAT technology. We integrate both approaches in a graphical modeling environment, enabling modelers to use formal verification techniques without any special background knowledge. We experimentally evaluate the scalability of our approach.

Simplifying Firewall Setups by Using Offline Validation

Firewalls are crucial for the security of most networks and implemented by packet filters. Those packet filters can be considered the direct opposite of a simple-to-use system. Configured with complex commands in plain text files, only experts are able to understand or even modify such a setup. Recently, this process has been improved by using a combination of external tools, a graphical modeling environment, and a model checker, enabling more users to participate in the process and clearing the way to automatic testing. This paper revists this concept from a simplicity perspective and shows how the whole process can be simplified while simultaneously the level of abstraction is increased and new ways of verifying the result are possible.

Maestro – A model‐based systems engineering environment for complex electronic systems

AbstractIn this paper we present Maestro, a model‐based systems engineering (MBSE) environment for design and simulation of complex electronic systems using Orchestra—a simulation tool developed at Sandia National Laboratories. Maestro is deployed as a plugin for MagicDraw and uses Orchestra domain‐specific language (DSL) which is based on SysML. Maestro enables a model‐based design and analysis approach that replaces the traditional document‐based systems engineering process. It provides a unified graphical modeling environment to domain experts who have had to depend on drawing tools for defining system architecture and manual transcription of system topology in creating complex simulation models.

Automated verification of model transformations based on visual contracts

Model-Driven Engineering promotes the use of models to conduct the different phases of the software development. In this way, models are transformed between different languages and notations until code is generated for the final application. Hence, the construction of correct Model-to-Model (M2M) transformations becomes a crucial aspect in this approach. Even though many languages and tools have been proposed to build and execute M2M transformations, there is scarce support to specify correctness requirements for such transformations in an implementation-independent way, i.e., irrespective of the actual transformation language used. In this paper we fill this gap by proposing a declarative language for the specification of visual contracts, enabling the verification of transformations defined with any transformation language. The verification is performed by compiling the contracts into QVT to detect disconformities of transformation results with respect to the contracts. As a proof of concept, we also report on a graphical modeling environment for the specification of contracts, and on its use for the verification of transformations in several case studies.

Optimal Scheduling in Graphical Modeling Environments

Methods for controlling execution order in traditional textbased languages such as C and Fortran are well established. The transition to graphical programs has revealed some of the hidden issues inherent in any scheduling routine, specifically data dependency and data protection (in multirate systems). Graphical programming languages provided built-in diagnostics that allow users to analyze the data dependencies to develop optimal schedules from a data propagation perspective. This paper examines one heuristic that can be used to develop an optimal schedule for an arbitrary model.

Integrated analysis and design tool for the strut-and-tie method

Although the strut-and-tie method (STM) has recently emerged as a consistent and rational method for the design of discontinuity regions in structural concrete and is just now being incorporated into codes of practice, challenges have been encountered in its implementation. An integrated analysis and design tool CAST (computer aided strut-and-tie) was developed to advance the STM for overcoming these difficulties. The design features addressing the time-consuming aspects of the analysis and design process of the STM are presented. The extended analytical features facilitating research on the STM to exhibit good performance at serviceability and ultimate load levels are also described. The graphical modeling environment, which plays an important role in dealing with the graphically extensive design process in the STM, is briefly explained. Two application examples using this tool are provided to demonstrate the capabilities this tool offers.

VIRTUAL FACTORY SIMULATOR FRAMEWORK FOR LINE PROTOTYPING

Presented in the paper is a virtual factory simulator (VFS) framework as a 3D solid-based factory simulator to be used as a line prototyping tool for an AMS (automated manufacturing system). The VFS framework supports a 3D resource & factory layout modeling, a physical emulation, and a performance simulation: the physical emulation is used for the kinematics simulation, interference check between resources, and the generation & verification of device program; and the performance simulation is used for the material flow & control logic evaluation and system performance evaluation. The proposed VFS framework supports a fully integrated graphical modeling environment for emulation scenario modeling and material flow & control logic modeling. Therefore, the proposed VFS meets the modeling requirements of high modeling power, ease of model building & validation, and ease of communication with stakeholders compared to other commercial system. Based on the VFS framework, a virtual factory simulator named VM-Factory® has been developed in C++ with OpenGL and a DEVS engine, and its validity was demonstrated by applying it in constructing a virtual factory of an FMS (flexible manufacturing system).

Composition and Cloning in Modeling and Meta-Modeling

The Generic Modeling Environment (GME) is a configurable tool suite that facilitates the rapid creation of domain-specific model-integrated program synthesis environments. There are three characteristics of the GME that make it a valuable tool for the construction of domain-specific modeling environments. First, the GME provides generic modeling primitives that assist an environment designer in the specification of new graphical modeling environments. Second, these generic primitives are specialized to create the domain-specific modeling concepts through meta-modeling. The meta-models explicitly support composition enabling the creation of composite modeling languages supporting multiple paradigms. Third, several ideas from prototype-based programming languages have been integrated with the inherent model containment hierarchy, which gives the domain expert the ability to clone graphical models. This paper explores the details of these three ideas and their implications.

WEST: modelling biological wastewater treatment

Modelling is considered to be an inherent part of the design and operation of a wastewater treatment system. The models used in practice range from conceptual models and physical design models (laboratory-scale or pilot-scale reactors) to empirical or mechanistic mathematical models. These mathematical models can be used during the design, operation and optimisation of a wastewater treatment system. To do so, a good software tool is indispensable. WEST is a general modelling and simulation environment and can, together with a model base, be used for this task. The model base presented here is specific for biological wastewater treatment and is written in MSL-USER. In this high-level object-oriented language, the dynamics of systems can be represented along with symbolic information. In WEST's graphical modelling environment, the physical layout of the plant can be rebuilt, and each building block can be linked to a specific model from the model base. The graphical information is then combined with the information in the model base to produce MSL-EXEC code, which can be compiled with a C++ compiler. In the experimentation environment, the user can design different experiments, such as simulations and optimisations of, for instance, designs, controllers and model fits to data (calibration).

New Graphical Modeling Environments

Simulation modeling is the operation over time of a mathematical model that represents the structure and dynamics of a system for the purpose of observing its behavior under controlled or experimental conditions (Berryman and Pienaar 1974). Models are used to create an orderly and logical representation of the underlying relationships among the components of the system. They long have been needed in ecological research because of the complexity of ecosystems, the variability of living organisms, the often unpredictable effects of human manipulation, and the long time scales sometimes necessary in ecological research (Jeffers 1982). In entomology, early research in integrated pest management used simulation as a tool for understanding complex agroecosystems and in designing optimal management strategies (Coulson and Saunders 1987). Simulation models currently are used by entomologists for a variety of reasons, ranging from basic research in ecological theory to the design of optimal management practices for specific pest situations. Despite their utility, many entomologists know little about the construction and proper use of models. Some reasons for this are the lack of a quantitative background and the avoidance of learning a complex and specialized subdiscipline of the field comprised of mathematics, engineering, and computer science. However, relatively recent advances in computer science, especially in object-oriented programming and sophisticated graphical user interfaces, promise to make modeling accessible to all interested entomologists.

A comprehensive modeling environment for the simulation of groundwater flow and transport

A comprehensive graphical modeling environment has been developed to address the needs of the computer simulation of groundwater flow and transport. The Department of Defense Groundwater Modeling Systems (GMS), developed at the Engineering Computer Graphics Laboratory at Brigham Young University, is part of a multi-year project funded through the Department of Defense, Department of Energy and Environmental Protection Agency. GMS is a graphically based software tool providing facility through all aspects of the groundwater flow and transport modeling process. Facilities include geometric modeling of hydrostratigraphy, two- and three-dimensional mesh generation, graphically based model input for specific flow and transport codes, interpolation and geostatistics as well as complete three-dimensional scientific visualization.

Computerized Tool for Hierarchical Simulation Modeling

Advancements in computing have enabled the development of effective tools for the modeling and analysis of construction operations. In particular, recent developments in object-oriented and event-driven programming were used by the writers in the development of a hierarchical, modular, and graphical environment for simulation-based planning of construction projects. This system, termed hierarchical simulation modeling (HSM) method, is specifically geared toward modeling the uncertain nature of conditions under which projects are implemented and the dynamic utilization of resources in construction. The modeling concepts, internal structure, implementation, and working of this environment are described in this paper. “Model definition,”“translation,”“simulation,” and “report generation” are the four internal modules of this system. One of the key concepts highlighted in this paper is the use of an object-oriented paradigm for developing modeling objects that have “graphics” and “simulation” properties that allow development of an interactive graphical simulation modeling environment.

A process-based approach to value-added construction — the CYCLONE/DISCO system

Recently, the study of processes and of non value-adding tasks at the process level has enjoyed a renaissance in the manufacturing sector because of the emphasis on total quality management and the work of W. Edwards Deming and others. Interest by the construction industry in the study of processes at this level has been negligible. In order to achieve better quality in construction, the industry must become more process oriented and involved in the study of resource interaction. The CYCLONE modeling system provides an environment for flow charting and studying the interaction of resources within a construction process. The DISCO program which is integrated with the CYCLONE modeling system provides a graphical modeling and simulation environment which facilitates the analysis of construction operations using simulation techniques. The CYCLONE modeling format and the DISCO program interface constitute a foundation upon which improved process design and efficiency can be established. Key words: construction management, simulation, flow modeling, computer methods, construction processes.