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1.
This paper presents a formal mathematical framework for the use of the morphological matrix in a computerized conceptual design framework. Within the presented framework, the matrix is quantified so that each solution principle is associated with a set of characteristics such as weight, cost, performance, etc. Selection of individual solutions is modeled with decision variables and an optimization problem is formulated. The applications are the conceptual design of subsystems for an Unmanned Aerial Vehicle and an aircraft fuel transfer system. Both the system models and the mathematical framework are implemented in MS Excel.  相似文献   

2.
G.  B. 《Computer aided design》2000,32(14):877-887
Due to the highly complex and informal data that has to be managed in the conceptual design this early design phase still lacks of suitable computer support. Furthermore, existing approaches towards a computer aided conceptual design are insufficiently integrated with the downstream applications of the product development process. The paper therefore introduces an approach towards a feature-based integrated product model that incorporates a feature-based representation scheme for capturing product semantics handled in the conceptual design phase and links early design with part and assembly modelling.  相似文献   

3.
In this work, we present an automatic code generation process from conceptual models. This process incorporates the use of design patterns in OO-Method, an automated software production method, which is built on a formal object-oriented model called OASIS. Our approach defines a precise mapping between conceptual patterns, design patterns and their implementation. Design patterns make the code generation process easy because they provide methodological guidance to go from the problem space to the solution space. In order to understand these ideas, we introduce a complete code generation process for conceptual models that have dynamic specialization relationships. This proposal can be incorporated into CASE tools, making the automation of the software production process feasible.  相似文献   

4.
This paper presents a summary of research into the development and implementation of a domain-independent, computer-based model for the conceptual design of complex mechanical systems [1]. The creation of such a design model includes the integration of four major concepts: (1) the use of a graphical display for visualizing the conceptual design attributes: (2) the proper representation of the complex data and diverse knowledge reguired to design the system; (3) the integration of quality design methods into the conceptual design: (4) the modeling of the conceptual design process as a mapping between functions and forms. Using the design of an automobile as a case study, a design environment was created which consisted of a distributed problem-solving paradigm and a parametric graphical display. The requirements of the design problem with respect to data representation and design processing were evaluated and a process model was specified. The resulting vehicle design system consists of a tight integration between a blackboard system and a parametric design system. The completed system allows a designer to view graphical representations of the candidate conceptual designs that the blackhoard system generates.  相似文献   

5.
《Computers in Industry》2014,65(9):1242-1252
Ontologies are structural components of modern information systems. The taxonomy, the core of an ontology, is a delicate balance between adequacy considerations, minimal commitments and implementation concerns. However, ontological taxonomies can be quite restrictive and entities that are commonly used in production and services might not find room in a official or de facto standard or ontological system. This mismatch between the company's view and the ontological constraints can limit or even jeoparize the adoption of modern formal ontologies in industry. We study the roots of this problem and individuate a general set of principles to relate the ontology and those non-ontological entities that are yet important for the core business of the company. We then introduce a theoretically sound and formally robust approach to expand a given ontology with new dependency relations, which make available information regarding the non-ontological entities without affecting the consistency of the overall information system.  相似文献   

6.
Contradictions caused by the various design constraints present increasing challenges to efficiency and innovation in product development. TRIZ provides Inventive Principles (IPs) and Contradiction Matrix that are the most frequently applied in conflict resolution. However, the high-level abstraction and subjective selection of IPs inhibit achieving the transformation process from paradoxical states to physical structures. To fill this gap, a contradiction solving method by integrating deep learning and technological evolution patterns for product conceptual design is proposed, which illustrates the mechanism of contradiction transition from the perspective of system evolution and supplies a systematic and model-based design approach. Firstly, generic engineering parameters are extracted to define the underlying contradictions transformed from critical defects which are found out through function modeling and root-conflict analysis. Then, a fully-connected deep neural network with excellent performance is developed to uncover the non-linear relationships between engineering parameters and evolution patterns. Finally, an evolution tree based on the predicted patterns is constructed to visualize transformation potentials of a technical system and help designers generate innovative specific solutions. In addition, a case study concerning design conflict resolution for beat-up system of three-dimensional tubular weaving machine is used to validate the adaptability and reliability of the proposed approach.  相似文献   

7.
It is important to articulate the objectives and underlying assumptions behind a growing body of experimental research in conceptual modeling. We provide four guidelines for developing materials for experiments that evaluate conceptual modeling techniques, under the assumption that a primary purpose of conceptual modeling is to facilitate communication between analysts and users in validating domain knowledge during systems development. These guidelines assist in developing experimental materials that support meaningful tests of domain semantics. We present empirical evidence indicating the value of two of the guidelines. We also evaluate selected recent experiments on conceptual modeling with respect to the guidelines.  相似文献   

8.
With the growing popularity of large-scale collaborative ontology-engineering projects, such as the creation of the 11th revision of the International Classification of Diseases, we need new methods and insights to help project- and community-managers to cope with the constantly growing complexity of such projects. In this paper, we present a novel application of Markov chains to model sequential usage patterns that can be found in the change-logs of collaborative ontology-engineering projects. We provide a detailed presentation of the analysis process, describing all the required steps that are necessary to apply and determine the best fitting Markov chain model. Amongst others, the model and results allow us to identify structural properties and regularities as well as predict future actions based on usage sequences. We are specifically interested in determining the appropriate Markov chain orders which postulate on how many previous actions future ones depend on. To demonstrate the practical usefulness of the extracted Markov chains we conduct sequential pattern analyses on a large-scale collaborative ontology-engineering dataset, the International Classification of Diseases in its 11th revision. To further expand on the usefulness of the presented analysis, we show that the collected sequential patterns provide potentially actionable information for user-interface designers, ontology-engineering tool developers and project-managers to monitor, coordinate and dynamically adapt to the natural development processes that occur when collaboratively engineering an ontology. We hope that presented work will spur a new line of ontology-development tools, evaluation-techniques and new insights, further taking the interactive nature of the collaborative ontology-engineering process into consideration.  相似文献   

9.
Creative conceptual design: Extending the scope by infused design   总被引:2,自引:0,他引:2  
Many methods that support human creativity by manual or computational means have been proposed in the past. They rely on the assumption that following a certain process of reasoning might lead to generating ideas considered creative. We start by defining creativity as a capability that enables the creation of systems that are patentable. We review the state-of-the-art of creative conceptual design and organize it with a framework. Subsequently, we present a method called infused design that guarantees the generation of design solutions by transforming systems and methods from remote disciplines. In many cases, these solutions would be deemed creative. Finding these systems and their transformations is done through a process based on the underlying discrete mathematical representation. This process is partially supported by a computer tool.We describe the method of infused design and illustrate its operation through part of the results achieved until now, including designing a new active torque amplifier system. We further demonstrate its benefits through other examples. We discuss the relation of infused design with other creativity or design methods and conclude with future developments of the method.“A well-directed imagination is the source of great deeds.”Chinese proverb  相似文献   

10.
In recent years, ontology-driven reference models have gained much attention in the literature due to their potential key role in activities such as complex information modeling and semantic interoperability. The engineering process of these conceptual models should account for different phases addressing different areas of concern. In an initial phase of conceptual domain modeling, the target modeling artifacts should be constructed with the goal of maximizing quality attributes such as expressivity and truthfulness to the represented domain in reality. In a subsequent development phase, the resulting domain models can be used to guide the design decisions in the construction of different implementation artifacts addressing different computational concerns. In this paper, we present a philosophically sound, cognitively-oriented and formally characterized foundational theory of objects and tropes (property-instances). Moreover, we use this theory to bring about engineering contributions to both the aforementioned phases of ontology-driven conceptual modeling. Firstly, we show how this theory has been used to (re)design a system of modeling primitives underlying the conceptual domain modeling language OntoUML. Furthermore, we provide precise directives on how to map conceptual domain models in this language to their implementation in less-expressive computationally-oriented codification languages. In particular, we address here a mapping strategy to OWL (Web Ontology Language) that partially preserves the modal-temporal semantics of OntoUML. Finally, we discuss computational support for the proposed approach in terms of conceptual model construction, automatic transformation and temporal querying.  相似文献   

11.
Existing techniques for developing large scale complex engineering systems are predominantly software based and use Unified Modeling Language (UML). This leads to difficulties in model transformation, analysis, validation, verification and automatic code generation. Currently no general frameworks are available to bridge the concept-code gap rampant in design and development of complex, software-intensive mechatronic systems called cyber-physical systems. To fill this gap and provide an alternative approach to Object Management Group’s UML/SysML/OCL combination, we propose: Bond Graph based Unified Meta-Modeling Framework (BG-UMF). BG-UMF is a practical and viable alternative and uses a novel hybrid approach based on model unification and integration. The focus is on conceptual design and development of executable models for large systems. The viability of the framework is demonstrated through an application scenario: conceptual design and development of a navigation and control system for a rotor-craft UAV.  相似文献   

12.
A framework for empirical evaluation of conceptual modeling techniques   总被引:1,自引:0,他引:1  
The paper presents a framework for the empirical evaluation of conceptual modeling techniques used in requirements engineering. The framework is based on the notion that modeling techniques should be compared via their underlying grammars. The framework identifies two types of dimensions in empirical comparisons—affecting and affected dimensions. The affecting dimensions provide guidance for task definition, independent variables and controls, while the affected dimensions define the possible mediating variables and dependent variables. In particular, the framework addresses the dependence between the modeling task—model creation and model interpretation—and the performance measures of the modeling grammar. The utility of the framework is demonstrated by using it to categorize existing work on evaluating modeling techniques. The paper also discusses theoretical foundations that can guide hypothesis generation and measurement of variables. Finally, the paper addresses possible levels for categorical variables and ways to measure interval variables, especially the grammar performance measures.  相似文献   

13.
Ontologies for conceptual modeling: their creation, use, and management   总被引:16,自引:0,他引:16  
Although ontologies have been proposed as an important and natural means of representing real world knowledge for the development of database designs, most ontology creation is not carried out systematically. To be truly useful, a repository of ontologies, organized by application domain is needed, along with procedures for creating and integrating ontologies into database design methodologies. This research proposes a methodology for creating and managing domain ontologies. An architecture for an ontology management system is presented and implemented in a prototype. Empirical validation of the prototype demonstrates the effectiveness of the research.  相似文献   

14.
We propose a new method that eases the definition of integrity constraints in object-oriented conceptual modeling languages. The essence of the method is to represent constraints by special operations that we call constraint operations. The formal specification of these operations is the definition of the corresponding constraints. The method allows the specialization of constraints and the definition of exceptions. The main application of the method is for static constraints. However, a variant of it can also be applied for creation-time and deletion-time constraints, two particular classes of temporal constraints. The method can be adapted to any object-oriented language, and we show its adaptation to the UML. We also show that our method has several advantages over existing methods.  相似文献   

15.
This paper presents a state of the art review of existing research, projects, and applications in the domain of collaborative conceptual design, based on the Internet and Web technologies. The purpose of the review is to understand the needs for conceptual engineering design, to clarify the current conceptual design practice, to classify the available technologies, and to study the future trend in this area. The emphasis of this paper is to briefly outline the methodologies, architectures, and tools developed for the projects reviewed in this paper. It also uncovers approaches to conflict resolution and team/project management, as they are vital to a successful engineering design in a collaborative environment. More than 80 journal and conference papers and about 20 projects are reviewed based on the primary focus mentioned above. The selected research works are further categorised into several areas based on the application domain, design theory, and the technology used for implementation. The selected research projects and applications are basically for, but not limited to, the collaborative conceptual design.  相似文献   

16.
Many existing inductive learning systems have been developed under the assumption that the learning tasks are performed in a noise-free environment. To cope with most real-world problems, it is important that a learning system be equipped with the capability to handle uncertainty. In this paper, we first identify the various sources of uncertainty that may be encountered in a noisy problem domain. Next, we present a method for the efficient acquisition of classification rules from training instances which may contain inconsistent, incorrect, or missing information. This algorithm consists of three phases: ( i ) the detection of inherent patterns in a set of noisy training data; ( ii ) the construction of classification rules based on these patterns; and ( iii ) the use of these rules to predict the class membership of an object. The method has been implemented in a system known as APACS (automatic pattern analysis and classification system). This system has been tested using both real-life and simulated data, and its performance is found to be superior to many existing systems in terms of efficiency and classification accuracy. Being able to handle uncertainty in the learning process, the proposed algorithm can be employed for applications in real-world problem domains involving noisy data.  相似文献   

17.
18.
Although widely advocated as a tool for the conceptual modelling of data, the Entity-Relationship (E-R) model [4] and its extensions are generally lacking in constructs to model the dynamic nature of the real world, making them inadequate for designing temporal databases. This research first extends the E-R model to a Temporal Event-Entity-Relationship Model (TEERM), by introducing events as an additional construct. Second, a method is proposed for mapping this conceptual model into a temporal relational model for the logical design of temporal relational databases with a corresponding set of integrity constraints. The model is illustrated with an example and evaluated using a set of criteria proposed by Batini et al. [2]. The model appears to be expressive, simple and easy to use, and should, therefore, aid the temporal database design process significantly.  相似文献   

19.
ContextThere are many claimed advantages for the use of design patterns and their impact on software quality. However, there is no enough empirical evidence that supports these claimed benefits and some studies have found contrary results.ObjectiveThis empirical study aims to quantitatively measure and compare the fault density of motifs of design patterns in object-oriented systems at different levels: design level, category level, motif level, and role level.MethodAn empirical study was conducted that involved five open-source software systems. Data were analyzed using appropriate statistical test of significance differences.ResultsThere is no consistent difference in fault density between classes that participate in design motifs and non-participant classes. However, classes that participate in structural design motifs tend to be less fault-dense. For creational design motifs, it was found that there is no clear tendency for the difference in fault density. For behavioral design motifs, it was found that there is no significant difference between participant classes and non-participant classes. We observed associations between five design motifs (Builder, Factory Method, Adapter, Composite and Decorator) and fault density. At the role level, we found that only one pair of roles (Adapter vs. Client) shows a significant difference in fault density.ConclusionThere is no clear tendency for the difference in fault density between participant and non-participant classes in design motifs. However, structural design motifs have a negative association with fault density. The Builder design motif has a positive association with fault density whilst the Factory Method, Adapter, Composite, and Decorator design motifs have negative associations with fault density. Classes that participate in the Adapter role are less dense in faults than classes that participate in the Client role.  相似文献   

20.
Contemporary advancements in Information Technology and the efforts from various research initiatives in the AEC industry are showing evidence of progress with the emergence of building information modelling (BIM). BIM presents the opportunity of electronically modelling and managing the vast amount of information embedded in a building project, from its conception to end-of-life. Researchers have been looking at extensions to expand its scope. Sustainability is one such modelling extension that is in need of development. This is becoming pertinent for the structural engineer as recent design criteria have put great emphasis on the sustainability credentials in addition to the traditional criteria of structural integrity, constructability and cost. With the complexity of designs, there are now needs to provide decision support tools to aid in the assessment of the sustainability credentials of design solutions. Such tools would be most beneficial at the conceptual design stage so that sustainability is built into the design solution starting from its inception. The sustainability of buildings is related to life cycle and is measured using indicator-terms such as life cycle costing, ecological footprint and carbon footprint. This paper proposes a modelling framework combining these three indicators in providing sustainability assessments of alternative design solutions based on the economic and environmental sustainability pillars. It employs the principles of feature-based modelling to extract construction-specific information from product models for the purposes of sustainability analysis. A prototype system is implemented using .NET and linked to the BIM enabled software, Revit Structures™. The system appraises alternative design solutions using multi-criteria performance analysis. This work demonstrates that current process and data modelling techniques can be employed to model sustainability related information to inform decisions right from the early stages of structural design. It concludes that the utilized information modelling representations – in the form of a process model, implementation algorithms and object-based instantiations – can capture sustainability related information to inform decisions at the early stages of the structural design process.  相似文献   

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