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This paper explores a historical innovation created by Henry Muncaster: a stationary steam engine featuring a single-cylinder horizontal design with a crosshead trunk guide. Through the application of engineering graphics techniques, we have elucidated the functioning of this invention by developing a 3D CAD model based on the original drawings published in Model Engineer magazine in 1957. However, the geometric modeling process faced challenges due to missing and erroneous dimensions for several components. Consequently, dimensional, geometric, and movement constraints were applied to ensure the coherence and functionality of the 3D CAD model, alongside conducting an interference analysis. Ultimately, the proper alignment of the cylinder and crosshead was ascertained, which is crucial for maintaining uniform forces and motions within the steam engine. This alignment is pivotal for achieving balanced operation, minimizing vibrations, and enhancing the overall efficiency of the invention. [ABSTRACT FROM AUTHOR]

The construction industry is the main economic support for all countries around the world in which continually adapting to meet competitive challenges around the global market. Nevertheless, the construction project is becoming much more complex and difficult to manage. This is because the construction project involves a large number of stakeholder, for example, the consultant companies, architects, engineers, building surveyors and quantity surveyors. The technology currently used in the construction industry is the AutoCAD (Automatic computeraided design). AutoCAD is a commercial software application for 2D and 3D computer-aided design (CAD) and drafting develop by Autodesk. Generally, all the drawing design from Autocad will be exchanged among the stakeholder in the form of paper. Information exchanged among them mostly involves a lot of documents and drawings. This practice creates errors because of documents and drawings are mostly in a paper-based format that is not properly managed which results in miscommunication among them. Having wrong information in the construction process could hinder the productivity of projects because in a construction project information is one of the important construction materials. Building Information Modeling (BIM) is one of the newly software in the architecture, engineering, and construction (AEC) industries to ensure all parties receive the right information. BIM technology is also an intelligent model of a building constructed digitally in the way of 3D. The software will generate model containing the information needed to support the construction, fabrication, and procurement activities that needed to realize the building. This paper will discuss on potential and benefits of BIM during pre-construction stage, construction stage and during post construction stage. [ABSTRACT FROM AUTHOR]

• A model-based feature information network (MFIN) links and retrieves data throughout the lifecycle. • From coordinate measurement datasets, MFIN automates updates to the computer aided design surfaces. • The framework creates connectivity between geometric inspection and stress analysis. • The automated flow of data can be used during the materials review board stages of manufacturing. • An example is given for making more informed decisions regarding maintenance, repair, or overhaul. Digital engineering relies on continuous and interoperable flow of data across the various stages within the product lifecycle, which permits engineers to make more-informed downstream decisions in the lifecycle. A model-based feature information network (MFIN) was developed to enable storing, tracking, and retrieving externally stored metadata in the context of the geometric features of the corresponding computer aided-design (CAD) model. In this paper, we use the MFIN framework to dynamically capture deviations in the part geometry via physical measurements, and to create a new instance of the CAD model and the associated structural analysis. The contribution of this work is the creation of automated workflow software, which enables engineers to improve decision making by assessing (i) as-manufactured part geometries that fall out of specifications during the materials review board or (ii) in-service damages in parts during the maintenance, repair, or overhaul stages of the lifecycle. We demonstrate a use case to assess the structural integrity of a turbofan blade that had experienced foreign object damages during service. The automated flow of information from geometric inspection within structural analysis, enabled by MFIN, presents opportunities for effectively assessing products by utilizing their current geometries and improving decision making during the product lifecycle. [Display omitted] [ABSTRACT FROM AUTHOR]

In this era of knowledge economy, appropriate management of the rapidly evolving knowledge is a real and urgent issue for factories and enterprises, in order to maintain the competitive edges. However, facing the onerous analysis required for understanding the long-term knowledge evolution, especially the evolving of empirical knowledge in the engineering field, effective and comprehensive modeling methods for knowledge evolution are absent. In this paper, a novel knowledge evolution modeling method is proposed for portraying the long-term evolution of empirical engineering knowledge (EEK) and assisting engineers in comprehending the evolving history. Three phases, EEK elicitation and formalization, EEK networks foundation, and family-tree evolution model construction, are included in the modeling method. This method is developed using natural language processing, semantic similarity calculation, fuzzy neural network prediction, clustering algorithm, and latent topic extraction techniques. To evaluate the performance of the proposed modeling method, an evolution model of empirical knowledge in computer-aided design (CAD) is constructed and then verified. Experimental results show that the proposed method outperforms the former approaches in feasibility and effectiveness, and hence opens up a better way of further understanding the long-term evolution course of EEK. [ABSTRACT FROM AUTHOR]

Advanced mobile applications demand low power and high performance systems. In this paper, a technology computer aided design (TCAD)-based feasibility investigation of a recently proposed area tunneling field effect transistor (FET) structure is carried out from the point of high volume and ultralow power mobile applications. We demonstrate that for realization of future ultralow power and high performance systems, unique properties of area tunneling class of tunnel FET structures need to be employed. These devices are realized by engineering the tunneling region profile and tunneling cross-sectional area. The optimized devices are found to leverage up to \sim7\times energy reduction when compared with the 20-nm node MOS device options while meeting the high performance targets. Device design insights for such an area tunneling class of tunnel FET structures are discussed in this paper for the first time. It is shown that by lowering the supply voltage below 0.5 V, up to 10\times reduction of the energy delay product is feasible by using area tunneling devices. [ABSTRACT FROM AUTHOR]

Research on computer-aided design for machine tools has been in the interest of many researchers for a long time and generated several new methods for different engineering applications. This paper introduces a case-based reasoning (CBR) method combined with SolidWorks application programming interface (API) for special purpose machines (SPMs). It presents an integrated system with focusing on the indexing and retrieval process for the design cases. An indexing mechanism was developed for SPMs, and two retrieval stages were applied to retrieve the optimum case. An illustrative example is included to demonstrate the proposed method and how this method combined with SolidWorks API will accelerate the design process for SPMs. [ABSTRACT FROM AUTHOR]

This paper deals with research into advanced hierarchical graph structures which have been developed for knowledge representation in computer-aided design and robotics. Complex real-life engineering problems still need useful graph-based models. A new approach to represent models preserving the intrinsic nature of problem structures using graphs with many hierarchies is proposed. Different types of hierarchical dependencies (geometrical, functional, etc.) between design parts can be expressed in one structure. Moreover, the possibility of selecting only problem-related hierarchies reduces the number of data to be analysed in the process of reasoning about considered designs. This approach is illustrated by applying multi-hierarchical graph structures to represent complex data used for robot control algorithms. [ABSTRACT FROM AUTHOR]

Abstract: Most complex projects in the Architecture, Engineering, and Construction (AEC) industries involve multi-disciplinary collaboration and the exchange of large building data set. Traditionally, the collaboration efforts across the disciplines have been based on the frequent exchange of 2D drawings and documents. However, during the past decade, the widespread adoption of object-oriented Computer-aided Design (CAD) tools has generated more interests in Building Information Modelling (BIM). A number of BIM-compliant applications such as analysis tools, model checkers and facility management applications are being developed. This paper develops a theoretical framework of technical requirements for using BIM-server as a multi-disciplinary collaboration platform. The methodologies that are used to develop the framework include focus group interviews (FGIs) with representatives from the diverse AEC disciplines, a case study of an Architectural project using a state-of-the-art BIM-server, and a critical review and analysis of current collaboration platforms that are available to the AEC industries. This paper concludes that greater emphasis should be placed on supporting technical requirements to facilitate technology management and implementation across disciplines. Their implications for user-centric technology development in design and construction industry are also discussed. [Copyright &y& Elsevier]

What information can or cannot be exchanged between different systems? Since the dawn of the computer-aided design and engineering era, interoperability has been an issue. The exchangeable set of information between different systems has been loosely defined as the intersection of information. Yet, as information flow has directionality, a general definition of 'intersection' is inadequate to define an exchangeable set of information. This paper proposes a new directive set operation, semantic intersection, and discusses which information can or cannot be exchanged between different systems using the concept of semantic intersection. This opens up the possibility of predetermining or calculating the exchangeable set of information between two or more systems or the possibility of automated generation of a standard product model between different systems. This paper focuses on data exchange between systems, but the proposed theory is also applicable to data exchange between human beings. [ABSTRACT FROM AUTHOR]

This paper presents results of transdisciplinary research on the development of a bioinspired computational framework for engineering design. This framework is intended to support design by addressing three critical design objectives, including novelty, optimality, and robustness. It provides several computational models and methods, which are inspired by fundamental processes occurring in nature, and discusses their potential for enhancing design. They include models and methods for evolutionary, developmental, and coevolutionary design. Their use is illustrated with examples from the area of steel structural design ranging from a simple cantilever beam design problem to a much more complex problem of designing wind bracings in tall buildings. The paper also shows how several methods and models can be integrated and form a coherent bioinspired computational framework for engineering design. [ABSTRACT FROM AUTHOR]

This paper is about tool support for knowledge-intensive engineering tasks. In particular, it introduces software technology to assist the design of complex technical systems. There is a long tradition in automated design problem solving in the field of artificial intelligence, where, especially in the early stages, the search paradigm dictated many approaches. Later, in the so-called modern period, a better problem understanding led to the development of more adequate problem solving techniques. However, search still constitutes an indispensable part in computer-based design problem solving—albeit many human problem solvers get by without (almost). We tried to learn lessons from this observation, and one is presented in this paper. We introduce design problem solving by functional abstraction which follows the motto: construct a poor solution with little search, which then must be repaired. For the domain of fluidic engineering we have operationalized the paradigm by the combination of several high-level techniques. The red thread of this paper is design automation, but the presented technology does also contribute in the following respects: (a) productivity enhancement by relieving experts from auxiliary and routine tasks; (b) formulation, exchange, and documentation of knowledge about design; (c) requirements engineering, feasibility analysis, and validation. [ABSTRACT FROM AUTHOR]

This paper introduces a new system that utilizes the advantages of boundary element analysis in structural engineering applications. A standardized building information model (BIM) for automated structural analysis and design of reinforced concrete plates based on the boundary element method (BEM) is proposed. Based on the model view definition approach, BIM standards are presented for the preprocessing and postprocessing of BEM analysis. Furthermore, standards are proposed for automated structural design of structural slab and beam elements based on the BEM analysis results. For each of the BIM components, standards are provided for the object structure, data flow, and graphical user interface (GUI). The extensibility of the software and applicability for a wide range of research and practical applications are considered in all the proposed standards. The system created can act as the basis for structural analysis and design of building floor and foundation problems. Object-oriented programming is used to implement the standards in a prototype. The prototype was verified by application to the solution of practical structural engineering problems. The performance of the proposed system is evaluated in terms of the modeling and the processing time required to analyze typical structural engineering applications using the prototype. [ABSTRACT FROM AUTHOR]

The widespread use of computer-aided drafting (CAD) systems within the engineering domain has provided significant advances in the capability to model design solutions. However, the focus of these systems on detailed design solutions has resulted in a corresponding lack of automated design assistants for the generation of conceptual design solutions, the primary reason being the incompatibility between the emphasis on geometric coordinates in detailed design and the emphasis on qualitative definitions in conceptual design. This paper presents one approach to bridging this representation gap, through the use of a qualitative geometric reasoner for integrated design (GRID). The paper presents a prototype GRID system that uses artificial intelligence representation and reasoning techniques to interpret CAD models and respond to qualitative geometric queries from automated design assistants within an integrated design environment. The expansion of qualitative geometric reasoning beyond spatial reasoning to include temporal and logical reasoning is introduced as a primary focus of the GRID system. [ABSTRACT FROM AUTHOR]

The Palazzo Lombardia Tower, located at the heart of the city of Milan, Italy, recently was completed. At 161.30 m high, the new building is currently the tallest in Italy and one of the most prominent features of the city skyline for many years to come. Given the strategic importance and the strong impact of the new building, it was decided to perform a series of dynamic excitation tests, with special emphasis on the Tower. Thus, it was possible to estimate its basic modal features and then compare them to the numerical simulation predictions provided by the same finite-element (FE) numerical analysis used for design. This offered the chance to start an important and interesting model-updating procedure, taking advantage of both the actual material properties measured during the construction phase and dynamic measurements, the latter having added significant insight to the structural behavior. The mechanical engineering department of the Polytechnic University of Milan was in charge of the design and execution of the tests. Professor F. Mola served as the structural designer of the building and also supervised the design and interpretation of the tests, together with the staff of ECSD Engineering and CAD DataConsult, who created the analytical model of the complete structure to be used as a benchmark for the experimental results. The tests provided an experimental validation of the modeling assumptions accuracy and of the robustness and reliability of the FE model in predicting the structural behavior. Moreover, the experimental validation of the FE model of the Tower was meant as the initial part of an intended continuous monitoring activity. This paper describes the main structural features of the Palazzo Lombardia Tower and those of the experimental tests. Also, the FE model is presented and the comparison between the numerically predicted and the experimentally derived modal properties is discussed. [ABSTRACT FROM AUTHOR]

Multiple sequence alignment is a crucial task in a number of biological analyses like secondary structure prediction, domain searching, phylogeny, etc. MSAProbs is currently the most accurate alignment algorithm, but its effectiveness is obtained at the expense of computational time. In the paper we present QuickProbs, the variant of MSAProbs customised for graphics processors. We selected the two most time consuming stages of MSAProbs to be redesigned for GPU execution: the posterior matrices calculation and the consistency transformation. Experiments on three popular benchmarks (BAliBASE, PREFAB, OXBench-X) on quad-core PC equipped with high-end graphics card show QuickProbs to be 5.7 to 9.7 times faster than original CPU-parallel MSAProbs. Additional tests performed on several protein families from Pfam database give overall speed-up of 6.7. Compared to other algorithms like MAFFT, MUSCLE, or ClustalW, QuickProbs proved to be much more accurate at similar speed. Additionally we introduce a tuned variant of QuickProbs which is significantly more accurate on sets of distantly related sequences than MSAProbs without exceeding its computation time. The GPU part of QuickProbs was implemented in OpenCL, thus the package is suitable for graphics processors produced by all major vendors. [ABSTRACT FROM AUTHOR]

Remote dynamic three-dimensional (3D) scene reconstruction renders the motion structure of a 3D scene remotely by means of both the color video and the corresponding depth maps. It has shown a great potential for telepresence applications like remote monitoring and remote medical imaging. Under this circumstance, video-rate and high resolution are two crucial characteristics for building a good depth map, which however mutually contradict during the depth sensor capturing. Therefore, recent works prefer to only transmit the high-resolution color video to the terminal side, and subsequently the scene depth is reconstructed by estimating the motion vectors from the video, typically using the propagation based methods towards a video-rate depth reconstruction. However, in most of the remote transmission systems, only the compressed color video stream is available. As a result, color video restored from the streams has quality losses, and thus the extracted motion vectors are inaccurate for depth reconstruction. In this paper, we propose a precise and robust scheme for dynamic 3D scene reconstruction by using the compressed color video stream and their inaccurate motion vectors. Our method rectifies the inaccurate motion vectors by analyzing and compensating their quality losses, motion vector absence in spatial prediction, and dislocation in near-boundary region. This rectification ensures the depth maps can be compensated in both video-rate and high resolution at the terminal side towards reducing the system consumption on both the compression and transmission. Our experiments validate that the proposed scheme is robust for depth map and dynamic scene reconstruction on long propagation distance, even with high compression ratio, outperforming the benchmark approaches with at least 3.3950 dB quality gains for remote applications. [ABSTRACT FROM AUTHOR]

Just as the power of the open-source design paradigm has driven down the cost of software to the point that it is accessible to most people, the rise of open-source hardware is poised to drive down the cost of doing experimental science to expand access to everyone. To assist in this aim, this paper introduces a library of open-source 3-D-printable optics components. This library operates as a flexible, low-cost public-domain tool set for developing both research and teaching optics hardware. First, the use of parametric open-source designs using an open-source computer aided design package is described to customize the optics hardware for any application. Second, details are provided on the use of open-source 3-D printers (additive layer manufacturing) to fabricate the primary mechanical components, which are then combined to construct complex optics-related devices. Third, the use of the open-source electronics prototyping platform are illustrated as control for optical experimental apparatuses. This study demonstrates an open-source optical library, which significantly reduces the costs associated with much optical equipment, while also enabling relatively easily adapted customizable designs. The cost reductions in general are over 97%, with some components representing only 1% of the current commercial investment for optical products of similar function. The results of this study make its clear that this method of scientific hardware development enables a much broader audience to participate in optical experimentation both as research and teaching platforms than previous proprietary methods. [ABSTRACT FROM AUTHOR]

Abstract: A software application, based on the Discrete Element Method (DEM), has been developed, using a modern object-oriented design and programming approach, in order to enable the effective simulation of multi-drum columns and colonnades under harmonic and earthquake excitations. This paper examines specifically colonnade systems with two rows of columns, one over the other, under various ground motions. The computed results show that the frequency content of the ground motion affects mostly the response. The displacements of the upper level columns in respect to the displacements of the lower level columns are affected more by the frequency content of the excitation. [Copyright &y& Elsevier]

A virtual factory is a very useful model for analyzing complex manufacturing systems that cannot be described by analytical or mathematical models. One of the main obstacles in the simulation of a virtual factory comes from the huge size of the geometric data involved. This paper proposes an efficient method for reducing that data volume through introducing a simplification method for virtual factories that consist of prismatic solid models containing complex internal features. The proposed method allows a determination of whether the faces of a virtual factory represent internal features (invisible), which are unnecessary to the simulation and may therefore be eliminated. The proposed approach uses a graphics board optimized to render a given scene and reverses the process; after drawing a scene, we try to identify the entities that are visible. The proposed algorithm splits the given triangles into visible groups, and for each visible group, we can then draw the mesh on a pixel map from the corresponding viewing direction. By querying the colors that appear on the pixel map, it is possible to determine the visible triangles. When the visible triangles are known, it is possible to remove the internal features by removing those invisible triangles from the triangular mesh. [ABSTRACT FROM AUTHOR]

Abstract: The successful design and development of a complex system, like the ITER test blanket module (TBM) warrants the need of extensive computer aided engineering (CAE) activities. In this light, a sophisticated numerical flow solver (‘SC/Tetra’ by CRADLE®), with a robust CAD interface, has been used to develop and evaluate helium coolant flow schemes for a solid breeder test blanket module design currently proposed by the US for testing in ITER. The traits of a particular cooling strategy for the TBM, namely the exit temperature of coolant, overall pressure drop, uniformity of temperature in the structure, robustness against transients, etc. can only be predicted by carrying out a complete three dimensional thermal-fluid analysis of the system in its entirety including all the structural and fluid components. The primary objective of this paper is to introduce the procedure for carrying out complex thermo-fluid analysis using the complete three dimensional CAD models of the TBM to evaluate the performance of TBM cooling schemes and to illustrate the way in which the results from these analyses can be useful towards a systematic design of an effective cooling solution for the test blanket module. [Copyright &y& Elsevier]

Design of fair surfaces over irregular domains is a fundamental problem in computer-aided geometric design (CAGD), and has applications in engineering sciences (in aircraft, automobile, ship science etc.). In the design of fair surfaces over irregular domains defined over scattered data, it was widely accepted till recently that the classical Delaunay triangulation be used because of its global optimum property. However, in recent times it has been shown that for continuous piecewise linear surfaces, improvements in the quality of fit can be achieved if the triangulation pattern is made dependent upon some topological or geometric property of the data set or is simply data dependent. The fair surface is desired because it ensures smooth and continuous surface planar cuts, and these in turn ensure smooth and easy production of the surface in CAD/CAM, and favourable resistance properties. In this paper, we discuss a method for construction of C¹ piecewise polynomial parametric fair surfaces which interpolate prescribed ℜ³ scattered data using spaces of parametric splines defined on ℜ³ triangulation. We show that our method is more specific to the cases when the projection on a 2-D plane may consist of triangles of zero area, numerically stable and robust, and computationally inexpensive and fast. Numerical examples dealing with surfaces approximated on plates, and on ships have been presented. [ABSTRACT FROM AUTHOR]

Abstract: Infrastructure managers rely on capabilities of Computer-Aided Design (CAD) and Geospatial Information Systems (GIS) for making decisions during the implementation of engineering tasks. However, despite the fact that there are domains in which both CAD and GIS are used and despite the overlaps between the data and operations they support, CAD and GIS have been developed independently over many years resulting in platforms that are not easily integrated. Engineers in infrastructure management must gain knowledge and skills in both CAD and GIS to perform infrastructure management tasks. In most cases, they need to manually transfer data queried from one system to another, due to the heterogeneous nature, such as data and operations heterogeneity, of CAD and GIS. Interoperability is seen as a solution to overcome the problems associated with heterogeneous environments and may occur at different levels and for different purposes. In this paper, we discuss the need for semantic interoperability between GIS and CAD and present an ontological engineering methodology as a possible means to enable this interoperability. This methodology uses ontological-based techniques for resolving the semantic differences in queries requiring CAD and GIS data and operations. [Copyright &y& Elsevier]

Methodology developed for designing and investigation of the characteristics of technological and exploitation surface layer aiming to provide conditions under which a surface layer with predictable characteristics of mate surfaces will be generated is described in the paper. Methodology possesses syntheses of performances for creation and analysis of models for surfaces generated with different types of machining, and import of measured surfaces data. Basis for the surface layer modelling with deterministic and stochastic structure is method of kinematical–geometrical copying of the cutting tool geometry as a function of machining conditions and method of virtual modelling comprising synthesis of theoretical functions simulating also disturbing factors appearing in the process of material removal. Definition of correlation existing between the parameters describing surface geometrical structure and technological parameters for surface machining is also enabled. These activities are performing with support of the originally created software (CADSIM) designed in Visual Basic in interaction with MS Access, AutoCAD and MATLAB. [Copyright &y& Elsevier]

Engineering design focuses on the development of products and artefacts to satisfy the specified function. Although considerable advances have been made over the last two decades in functional modelling, there is not very much progress on commercial Computer-Aided Design (CAD) systems that really aid the designer in converting functional specifications to concept variants. Based on our previous work on Behaviour-driven Function-Environment-Structure (B-FES) modelling framework, this paper presents a functional design software system, called "FuncDesigner", to support the functional design of mechanical products through functional reasoning steps, including causal behavioural reasoning and functional decomposition. A function object library and a behaviour object library have been developed as well to serve as the knowledge base for the computerised functional modelling environment. The proposed functional design software system has been evaluated with a design example of a terminal insertion unit in an automatic assembly system for manufacturing electronic connectors. [ABSTRACT FROM AUTHOR]

This paper presents a cooperative transaction model for shared engineering databases which provides a higher degree of concurrency and process parallelism in CAD. As opposed to traditional transaction models where intra-transaction results are isolated, the presented model allows exchanging and sharing of data and supports the integration of subresults into a common solution. The realization of the transaction system is based on concepts of active and object-oriented database systems. [Copyright &y& Elsevier]

Directional relays use voltage as the polarizing quantity. When three-phase faults occur close to the relay bus, the available voltage becomes nearly zero and this creates a problem in estimation of the fault direction. The capacitor coupling voltage transformer subsidence transients add to this problem. The memory voltage used as the polarizing quantity at these situations is a compromise. This paper highlights these issues and proposes a simple solution using the power-flow direction in addition to other information. The performance of the technique is evaluated through simulation in Power System Computer Aided Design. [ABSTRACT FROM AUTHOR]