Interoperability is the capability of multiple parties and systems to collaborate and exchange information and matter to obtain their objectives. Interoperability challenges call for a model-based systems engineering approach. This paper describes a conceptual modeling framework for model-based interoperability engineering (MoBIE) for systems of systems, which integrates multilayered interoperability specification, modeling, architecting, design, and testing. Treating interoperability infrastructure as a system in its own right, MoBIE facilitates interoperability among agents, processes, systems, services, and interfaces. MoBIE is founded on ISO 19450 standard-object-process methodology, a holistic paradigm for modeling and architecting complex, dynamic, and multidisciplinary systems-and allows for synergistic integration of the interoperability model with system-centric models. We also discuss the implementation of MoBIE with the unified modeling language. We discuss the importance of interoperability in the civil aviation domain, and apply MoBIE to analyze the passenger departure process in an airport terminal as a case-in-point. The resulting model enables architectural and operational decision making and analysis at the system-of-systems level and adds significant value at the interoperability engineering program level.

Technical reports and papers may be represented by a fundamental model, which can take the form of a block diagram, a state-machine, a flow diagram, or alternatively some ad hoc chart. This basic scheme can convey better the true value of otherwise verbose and potentially encumbered narrative-based specifications. We present a model-based methodology for authoring technical documents. The underlying idea is to first formalize the system to be specified using a conceptual model, and then automatically generate from the tested and verified model a humanly-readable text in a subset of English we call Tesperanto. This technical documents' authoring methodology is carried out in an integrated bimodal text-graphics document authoring environment. The methodology was evaluated with the International Organization for Standardization standards and a medical robotics case study. The evaluation resulted in tangible improvements in the quality and consistency of international standards. Further, it can serve to document complex dynamics among agents, such as interaction between an operation room technician robot and the surgeon, suggesting that it could be applied to represent and bring value to other types of technical documents.

Traditionally, Software Engineering (SWE) and Systems Engineering (SE) were almost different disciplines with little overlap and with a different set of approaches and concepts. Yet, both SWE and SE reflect two sides of the same coin: both revolve around development and lifecycle support of systems. While SWE focuses on software-intensive systems, SE has focused on systems in general. However, most systems nowadays not only combine hardware and software, ever more intertwined and increasingly interdependent, they also comprise humans and organizations as stakeholders. This work aims to underline the importance of the holism as highly effective approach to both SWE and SE as it is the result of a huge and very representative set of philosophical investigations, partially illustrated in this work, assuming that the historical distinction between SWE and SE is becoming ever less relevant and that it is high time they be treated as one overarching discipline provided with a minimal ontology in order to facilitate the conceptual modelling process and improve models understandability. We propose the Object Process Methodology (OPM), together with its holistic approach to systems modelling and simulation, as main building block of the bridge between SWE and SE disciplines with respect the issues above.

Model-Based Systems Engineering (MBSE) is gradually becoming an acceptable good practice, especially for large-scale complex systems. The variety of modeling languages enables detailed representation of domain-specific knowledge of different aspects of a system. Semantic Web concepts provide opportunities for easier and more efficient collaboration between design and verification teams using different modeling tools. IBM Semantic Mediation Container (SMC) is a tool interoperability platform, allowing mediation and synchronization among models in different languages based on their ontologies. We propose integrating into SMC the ability to translate Object-Process Methodology (OPM), the emerging ISO 19450 Standard, which provides a holistic view of the system's function, structure, and behavior. In this paper we describe the first integration stages - defining the OPM ontology in a way that conforms to Semantic Web specifications and developing a module for exporting OPM models from their visual representation to and back from Resource Description Framework (RDF). We discuss the scope of the ontology and different approaches of element representation. We portray the implementation of the export module as an extension to OPM CASE tool (OPCAT). The ontology and export module are validated by round-trip transformation of OPM models from their visual representation to RDF and back by experimenting with OPM experts.

We propose a model-based systems engineering approach for representing and analyzing the perception and consideration of the presence of external entities by systems. This approach is inspired by the conceptual model-based systems biology paradigm we have previously proposed. The notion of presence and absence of surrounding objects, or occurrence of surrounding processes, is becoming ever more critical in a world of highly-aware automation agents and the increasingly complex and stochastic environmental configurations in which these agents act. This problem is well-known in the biological modeling domain. System models usually focus on nominal, mainstream aspects and scenarios. Presence-related aspects are often assumed to pose no issue, and remain unattended in both the conceptual and actual system design phases. The Pareto rule-of-thumb of system design asserts that about 20% of design and development efforts cover the nominal, “sunny day” process, while the other 80% cover exceptions, alternative scenarios, failure modes, edge conditions, special settings, and emergencies. We propose an approach to extend the naïve, nominal system model by enriching it with notions of presence-awareness and sensitivity. This approach is facilitated by Object-Process Methodology, a holistic system and process modeling framework, currently being adopted as ISO standard 19450.

Domain-specific languages and model-driven development are two promising approaches for tackling the complexity of software systems development. However, creating domain-specific modeling languages is a complex and lengthy task which makes the creation of DSMLs only feasible in large and complex projects. To alleviate this difficulty, we developed OPM/D, a visual meta-modeling language for the definition of domainspecific modeling languages. Languages in OPM/D are defined via a static structural meta-model of the language and a set of validation rules that define the non-structural constraints of the language. The language editor is created on-the-fly through interpretation of the static structure and validation rules, minimizing the time between language definition and its use. Our approach has been applied to define a subset of the OPM modeling language, and a prototype tools is being developed using the Eclipse platform and technologies.

Physical-Informatical Essence Duality (PIED) is the parallel existence of an entity as both an independent, mostly physical object, and its informatical representation. System models tend to neglect or ignore this dual representation and the two parallel manifestations of model entities. This may result in erroneous modeling and realization, as representations can be partial and mistaken. Agent perception or capturing of an entity of interest is fundamental to the way it affects or interacts with the entity. The problem intensifies in models of complex systems and systems of systems, which must account for original embodiments and their multiple representations by various agents. This paper proposes a formal model-based approach and theory for detecting, capturing, representing, and controlling this physical-informatical duality in system models. We illustrate the proposed semantics via formal object-oriented epistemic logic semantics and via Object-Process Methodology (OPM), the emerging ISO 19450 standard for Model-based Systems Engineering.

Design patterns provide reusable solutions for recurring design problems. They constitute an important tool for improving software quality. However, correct usage of design patterns depends to a large extent on the designer. Design patterns often include models that describe the suggested solutions, while other aspects of the patterns are neglected or described informally only in text. Furthermore, design pattern solutions are usually described in an object-oriented fashion that is too close to the implementation, masking the essence of and motivation behind a particular design pattern. We suggest an approach to modeling the different aspects of design patterns and semi-automatically utilizing these models to improve software design. Evaluating our approach on commonly used design patterns and a case study of an automatic application for composing, taking, checking, and grading analysis and design exams, we found that the suggested approach successfully locates the main design problems modeled by the selected design patterns.

While a number of modeling languages for constructing multiagent systems (MASs) have been suggested, none of them is widely accepted and used. A prominent reason for this is the gap that exists between agent-oriented modeling languages and the agent-based system modeling needs, including accessibility, flexibility, and expressiveness. This paper addresses the need for such a language by proposing object-process methodology (OPM)/MAS, an agent modeling language (AML) that extends OPM with an intermediate metamodel of the MAS domain. Three case studies and a comparison to contemporary AMLs demonstrate the novelty and benefits of OPM/MAS.

Domain engineering can simplify the development of software systems in specific domains. During domain analysis, the first step of domain engineering, the domain is modeled at an abstract level, providing guidelines for modeling applications within that domain. Drawbacks of existing domain analysis approaches include poor guidelines for domain-specific application modeling, insufficient validations capability, and limited usability. In this paper we apply the Application-based Domain Modeling (ADOM) to the Object-Process Methodology (OPM). This application requires the extension of OPM with a classification mechanism. Showing that the ADOM-OPM approach overcomes limitations of existing approaches, we further verify experimentally that the level of correctness of an ADOM extended OPM model is higher than that achieved without the extension. Finally, we ensure that the proposed extension does not degrade the generic vanilla form of OPM.

Access control is a central problem in privacy management. A common practice in controlling access to sensitive data, such as electronic health records (EHRs), is Role-Based Access Control (RBAC). RBAC is limited as it does not account for the circumstances under which access to sensitive data is requested. Following a qualitative study that elicited access scenarios, we used Object-Process Methodology to structure the scenarios and conceive a Situation-Based Access Control (SitBAC) model. SitBAC is a conceptual model, which defines scenarios where patient's data access is permitted or denied. The main concept underlying this model is the Situation Schema, which is a pattern consisting of the entities Data-Requestor, Patient, EHR, Access Task, Legal-Authorization, and Response, along with their properties and relations. The various data access scenarios are expressed via Situation Instances. While we focus on the medical domain, the model is generic and can be adapted to other domains.

Web service discovery is one of the main applications of semantic Web services, which extend standard Web services with semantic annotations. Current discovery solutions were developed in the context of automatic service composition. Thus, the “client” of the discovery procedure is an automated computer program rather than a human, with little, if any, tolerance to inexact results. However, in the real world, services which might be semantically distanced from each other are glued together using manual coding. In this article, we propose a new retrieval model for semantic Web services, with the objective of simplifying service discovery for human users. The model relies on simple and extensible keyword-based query language and enables efficient retrieval of approximate results, including approximate service compositions. Since representing all possible compositions and all approximate concept references can result in an exponentially-sized index, we investigate clustering methods to provide a scalable mechanism for service indexing. Results of experiments, designed to evaluate our indexing and query methods, show that satisfactory approximate search is feasible with efficient processing time.

Line detection algorithms constitute the basis fortechnical document analysis and recognition. Theperformance of these algorithms decreases as the qualityof the documents degrades. To test the robustness of linedetection algorithms under noisy circumstance, wepropose a document degradation mode, which simulatesnoise types that drawings may undergo during theirproduction, storage, photocopying, or scanning. Using ourmodel, a series of document images at various noise levelsand types can be generated for testing the performance ofline detection algorithms. To illustrate that our model isconsistent with real world noise types, we validated themethod by applying it to three line recognition algorithms.

As system complexity has increased, so has interest in reusing software components in early development phases. While most current modeling methods support design of generic parameterized frameworks or patterns and weaving them into specific models, they do not support open reuse, i.e., the ability to develop partially specified components and refine them in the target application. We introduce an open reuse formalism that is based on OPM/Web, an extension of object-process methodology for distributed systems and Web applications. Our open reuse is accomplished by a three-step process, consisting of designing reusable models, creating basic woven models, and enhancing their specification. We model a reusable component through partially specified environmental elements that are bound to concrete counterparts when the component is integrated into the system under development. Rules for modeling and combining components are defined and applied to a Web example.

Abstract Enterprise frameworks are a special class of application frameworks. They are distinguished from other application frameworks in terms of scale and focus. In terms of focus, application frameworks typically cover one particular aspect of an application, either a domain‐dependent aspect (e.g., billing in a web‐based customer‐to‐business ordering system), or a computational infrastructure aspect such as distribution, man‐machine interface, or persistence, etc. Generally, an application framework alone delivers no useful end‐user function. With infrastructure frameworks, we still have to plug in domain functionalities, while with domain frameworks, we need to set‐up the infrastructure. In contrast, enterprise frameworks embody a reference architecture for an entire application, covering both the infrastructure aspects of the application, and much of the domain‐specific functionality. Instantiating an enterprise framework is nothing short of application engineering, where the architecture and many of the components are reusable. While creativity and continual improvement may be the major ingredients for building a good application framework, anything related to enterprise frameworks, be it building, documenting, or instantiating them, is complex and requires careful design and planning. In this paper, we identify the issues involved in building, using, and maintaining enterprise frameworks, both from research and practical perspective. Copyright © 2002 John Wiley & Sons, Ltd.

Object-Process Methodology (OPM) is a system development and specification approach that combines the major system aspects - function, structure and behavior - within a single graphic and textual model. Having applied OPM in a variety of domains, this paper specifies an electronic commerce system in a hierarchical manner, at the top of which are the processes of managing a generic product supply chain before and after the product is manufactured. Focusing on the post-product supply chain management, we gradually refine the details of the fundamental, almost "classical" electronic commerce interaction between the retailer and the end customer, namely payment over the Internet using the customer’s credit card. The specification results in a set of Object-Process Diagrams and a corresponding equivalent set of Object-Process Language sentences. The synergy of combining structure and behavior within a single formal model, expressed both graphically textually yields a highly expressive system modeling and specification tool. The comprehensive, unambiguous treatment of this basic electronic commerce process is formal, yet intuitive and clear, suggesting that OPM is a prime candidate for becoming a common standard vehicle for defining, specifying and analyzing electronic commerce and supply chain management systems.

Content-based image retrieval relies on low-level image features such as color, texture and segmentation. Humans, however, search for images by their cognitive, deep meaning content. This paper introduces an approach and an algorithm for cognitive image retrieval. Each image is indexed by a visual object-process diagram (VOPD) that represents the image content at the cognitive level. Querying amounts to generating a VOPD that expresses the cognitive content of the sought image. Employing set-theoretic and graph-matching techniques, the algorithm ranks images in the database by their cognitive proximity to the query. A query example illustrates these new concepts.

The object-process methodology (OPM) specifies both graphically and textually the system's static-structural and behavioral-procedural aspects through a single unifying model. This model singularity is contrasted with the multimodel approach applied by existing object oriented system analysis methods. These methods usually employ at least three distinct models for specifying various system aspects: mainly structure, function, and behavior. Object modeling technique (OMT), the main ancestor of the unified modeling language (UML), extended with timed statecharts, represents a family of such multimodal object oriented methods. Two major open questions related to model multiplicity vs. model singularity have been: 1) whether or not a single model, rather than a combination of several models, enables the synthesis of a better system specification; and 2) which of the two alternative approaches yields a specification that is easier to comprehend. The authors address these questions through a double-blind controlled experiment. To obtain conclusive results, real time systems, which exhibit a more complex dynamic behavior than nonreal time systems were selected as the focus of the experiment. We establish empirically that a single model methodology, OPM, is more effective than a multimodel one, OMT, in terms of synthesis. We pinpoint specific issues in which significant diiferences between the two methodologies were found. The specification comprehension results show that there were significant differences between the two methods in specific issues.

Accurate and efficient vectorization of line drawings is essential for their higher level processing. We present a thinningless sparse pixel vectorization (SPV) algorithm. Rather than visiting all the points along the wire's black area, SPV sparsely visits selected medial axis points. The result is a crude polyline, which is refined through polygonal approximation by removing redundant points. Due to the sparseness of pixel examination and the use of a specialized data structure, SPV is both time efficient and accurate, as evaluated by our proposed performance evaluation criteria.

We have developed a Graphics Class Library (GCL) for graphics recognition using the object-process methodology and object-oriented implementation. The purpose of the library is to supply generic code for graphics recognition algorithms to be used as ready made and easily extendible components in future systems. The library consists of reusable classes of graphic objects that appear in engineering drawings as well as in other classes of line drawings. A generic integrated graphics recognition algorithm is at the basis of the library, serving useful standard operations required for graphics recognition applications. Copyright © 1999 John Wiley & Sons, Ltd.

The Machine Drawing Understanding System (MDUS) is an experimental CAD conversion system aimed at realizing the entire process of understanding mechanical engineering drawings, from scanning to 3D reconstruction. This paper describes the structure, algorithms and current performance of MDUS. The modular structure of the system provides for further improvements and makes it an ideal workbench for researchers wishing to test their own algorithms and incorporate them into the system.

We propose some principles for performance evaluation of graphics recognition algorithms. The main principles include using continuous values of matching degree instead of binary values, selecting objective-driven and comprehensive performance contents, and defining metrics quantitatively, normatively, objectively, and compatibly with the human vision evaluation.

We present an incremental arc segmentation algorithm, which recovers the vectorized arc fragments obtained by the vectorization of a piece of arc image in a stepwise fashion. Due to proper threshold selection and consistent checking of cocircularity of the assumed arc pieces, the algorithm accurately constructs arcs from the vector input. Nearly 200 synthetic arcs, ranging in radius from five to 50 pixels, in open angle from 1/8/spl pi/ to 2/spl pi/, and in thickness from one to nine pixels, are used in the experiments and evaluation. Parts of six real drawings, containing about 200 arcs, are also processed. The algorithm works well for arc segments greater than 10 pixels in radius, /spl pi//4 in angle, and one pixel in width.

Accurate arc segmentation, essential for high level engineering drawing understanding is very difficult due to noise, clutter, tangency, and intersections with other geometry objects. We present an application of a generic methodology for recognition of multicomponent graphic objects in engineering drawings to the segmentation of circular arcs. The underlying mechanism is a sequential stepwise recovery of components that are segmented as wire fragments during the sparse pixel vectorization process and meet a set of continuity conditions. Proper threshold selection and consistent checking of co-circularity of the assumed arc pieces result in an accurate arc segmentation method.

We propose that the vectorization process be divided into two separate steps: basic vectorization, which yields coarse vectors, and post processing, which results in fine vectors. We propose shape (medial axis and line width) preservation and time efficiency as two criteria for evaluating basic vectorization. Inspired by the idea of the OZZ algorithm, we present a thinningless algorithm-sparse pixel tracking-for basic vectorization. Rather than visiting all the points along the medial axis of the wire's black area, it sparsely visits selected medial points. The result is a crude polyline, which undergoes polygonal approximation to remove redundant points. Due to the sparse pixel examination and the use of a new data structure, the vectorization is highly time efficient, as well as accurate. Like OZZ, sparse pixel tracking preserves line width as well as the medial axis.

The object-process analysis (OPA) methodology combines ideas from object-oriented analysis (OOA) and data flow diagrams (DFD) to model both the structural and procedural aspects of a system in one coherent frame of reference. This is contrary to conventional object-oriented approaches, that use different tools to describe the structure and the behaviour of the system. The underlying observation of the OPA paradigm is that every thing in the universe of interest is either an object or a process, and that a process is not necessarily a method of a single object class. This opens the door for the possibility of modelling systems so that both their structural and procedural relations are represented within the same frame of reference, without suppressing each other. The two major differences between OPA and OOA are OPA's detachment of processes from objects and its recursive scaling capability. The OPA methodology has proven to model faithfully complex systems, such as computer integrated manufacturing, documentation and inspection and an intelligent computer-assisted instruction shell. This work lays down the foundations of OPA. It provides concise definitions of the basic building blocks of the method: objects, processes, classes, features, and the structural and procedural relations among them. The object-process diagram (OPD) is presented as an effective visualization tool that incorporates elements from both DFD and OOA. Due to synergy, both the information content and expressive power of OPD are greater than those of DFD and OOA diagrams combined.

Arcs are important primitives in engineering drawings. Extracting these primitives during the lexical analysis phase is a prerequisite to syntactic and semantic understanding of engineering drawings within the machine drawing understanding system. Bars are detected by the orthogonal zig-zag vectorization algorithm. Some of the detected bars are linear approximations of arcs. As such, they provide the basis for arc segmentation. An arc is detected by finding a chain of bars and a triplet of points along the chain. The arc center is first approximated as the center of mass of the triangle formed by the intersection of the perpendicular bisectors of the chords these points define. The location of the center is refined by recursively finding more such triplets and converging to within no more than a few pixels from the actual arc center after two or three iterations. The high performance of the algorithm, demonstrated on a set of real engineering drawings, is due to the fact that it avoids both raster-to-vector and massive pixel-level operations, as well as any space transformations.>

Thinning algorithms are an important sub-component in the construction of computer vision (especially for optical character recognition (OCR)) systems. Important criteria for the choice of a thinning algorithm include the sensitivity of the algorithms to input shape complexity and to the amount of noise. In previous work, we introduced a methodology to quantitatively analyse the performance of thinning algorithms. The methodology uses an ideal world model for thinning based on the concept of Blum ribbons. In this paper we extend upon this methodology to answer these and other experimental questions of interest. We contaminate the noise-free images using a noise model that simulates the degradation introduced by the process of xerographic copying and laser printing. We then design experiments that study how each of 16 popular thinning algorithms performs relative to the Blum ribbon gold standard and relative to itself as the amount of noise varies. We design statistical data analysis procedures for various performance comparisons. We present the results obtained from these comparisons and a discussion of their implications in this paper.>

A program has been initiated to automate certain radiographic measurements. The edge detection step is discussed. An edge detection model is presented for standard radiographs, which will be the basis for the measurements step. In particular, the edges of interest are modeled as a linear combination of basis functions. The problem of edge detection is then presented as a supervised pattern recognition problem in which the parameters of the basis functions are learned during the training phase, and the recognition phase uses these learned parameters to locate pixels that belong to edges. Since edges may appear in any direction, the mathematical tools to determine the gradient direction of the edge are developed.>

The authors try to explain why conversion of engineering drawings into CAD format has been stuck for so long in low-level operations such as vectorization, basic layer separation, and very limited symbol recognition, and what can be done to improve this situation. Based on their own expertise in syntactic and semantic analysis of technical drawings, they propose a scheme for achieving high-level conversion of engineering drawings into 3-D CAD models.>

The authors measure the performance of thinning algorithms in the ideal world of noise-free Blum ribbons. Differences in the performance of thinning algorithms emerge even when they are applied on noise-free ribbon images. The authors define an error criterion function based on the Hausdorf distance that measures the deviation between the ideal and actual output of the thinning algorithms. They illustrate the process of performance evaluation by the application of ten state of the art thinning algorithms to the same (large) set of input images. They present results that show the mean value of the normalized error for each algorithm over each population of images. How performance of an algorithm varies over different populations of images is examined.>

Producing a database of scanned document images for development or evaluation of OCR and document image understanding algorithms is neither easy nor inexpensive. The authors first briefly describe the makeup of a database of scanned document images of scientific and technical documents written in English which are being produced in a CD-ROM format. Then, the authors concentrate on the implementation methodology used to prepare the database. The methodology gives the protocols for each step of the database preparation, and the error model used for the estimation of the ground-truth errors that may exist in the database is discussed.>