bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trust Region Augmented Lagrangian Methods With Secant Hessian Updating Applied to Structural Optimization
Authors: Coster J. E. , Stander N. , Snyman J. A. 
Published: February 2021

Abstract
The problem of determining the optimal sizing design of truss structures is considered. An augmented Lagrangian optimization algorithm which uses a quadratic penalty term is formulated. The implementation uses a first-order Lagrange multiplier update and a strategy for progressively increasing the accuracy with which the bound constrained minimizations are performed. The allowed constraint violation is also progressively decreased but at a slower rate so as to prevent ill-conditioning due to large penalty values. Individual constraint penalties are used and only the penalties of the worst violated constraints are increased. The scheme is globally convergent. The bound constrained minimizations are performed using the SBMIN algorithm where a sophisticated trust-region strategy is employed. The Hessian of the augmented Lagrangian function is approximated using partitioned secant updating. Each function contributing to the Lagrangian is individually approximated by a secant update and the augmented Lagrangian Hessian is formed by appropriate accumulation. The performance of the algorithm is evaluated for a number of different secant updates on standard explicit and truss sizing optimization problems. The results show the formulation to be superior to other implementations of augmented Lagrangian methods reported in the literature and that, under certain conditions, the method approaches the performance of the state-of-the-art SQP and SAM methods. Of the secant updates, the symmetric rank one update is superior to the other updates including the BFGS scheme. It is suggested that the individual function, secant updating employed may be usefully applied in contexts where structural analysis and optimization are performed simultaneously, as in the simultaneous analysis and design method. In such cases the functions are partially separable and the associated Hessians are of low rank.
A Systems Approach to Structural Topology Optimization: Designing Optimal Connections
Authors: Jiang Tao , Chirehdast Mehran 
Published: February 2021

Abstract
In this paper, structural topology optimization is extended to systems design. Locations and patterns of connections in a structural system that consists of multiple components strongly affect its performance. Topology of connections is defined, and a new classification for structural optimization is introduced that includes the topology optimization problem for connections. A mathematical programming problem is formulated that addresses this design problem. A convex approximation method using analytical gradients is used to solve the optimization problem. This solution method is readily applicable to large-scale problems. The design problem presented and solved here has a wide range of applications in all areas of structural design. The examples provided here are for spot-weld and adhesive bond joints. Numerous other potential applications are suggested.
The Application of a Concurrent Design Optimization Tool to a Composite Panel for a Naval Ship Structure
Authors: Dirlik S. , Hambric S. , Azarm S. , Marquardt M. , Hellman A. , Bartlett S. , Castelli V. 
Published: February 2021

Abstract
A prototype concurrent design optimization tool, named CELS for Concurrent Engineering of Layered Structures, has been developed. This tool can be used to analyze and/or optimize the conceptual design of a composite panel for Naval ship topside structures. CELS integrates five technology modules: (1) electromagnetic interference, (2) radar cross section, (3) structures, (4) cost, and (5) weight. Two optimization methods drive the integration of the technology modules. These methods include: (i) a local optimizer based on feasible sequential quadratic programming, and (ii) a global optimizer based on an exhaustive search. To obtain an objectively balanced design, “goodness” measures are allocated for each objective or constraint function. These measures, via a graphical user interface, allow topside designers to easily and quickly assess the impact of their decisions on various technologies. The utility and capability of CELS are demonstrated via the design of a topside composite panel. The design study shows that CELS can be easily adapted to different topside conceptual design problems, and that design tradeoffs can be performed quickly and used in decision making.
Mixed Continuous Variable and Catalog Search Using Genetic Algorithms
Authors: Senin Nicola , Wallace David R. , Jakiela Mark J. 
Published: February 2021

Abstract
In this paper a general design and catalog representation is proposed and implemented. The representation is applied to mixed continuous variable and catalog search using genetic algorithms. The representation addresses a number of common catalog search design scenarios. In addition to catalogs of static data (e.g., different sizes of pipes), it is possible to model/search subdesigns that can provide performance data based upon operating conditions. The use of catalog hierarchies allows the search to simultaneously consider catalogs from different vendors and at different levels of detail, therefore achieving the capability of modeling solutions containing general information. The capabilities of the representation are demonstrated through an object-oriented computer implementation that uses a genetic optimization and search algorithm.
Modeling of Ram Extrusion Process and Optimal Die Design
Authors: Deng Qingwen , Lin Yuyi 
Published: February 2021

Abstract
This paper presents a one-dimensional analytical model of the ram extrusion process of a powdered material and a procedure for optimizing the shape of the extrusion die. Powdered coal mixed with water and asphalt was used as the extrudate material in the model development. The analytical model relates the pressure at the entrance of the die to the exit pressure of the die. Certain key parameters of the model were obtained from experiments. The comparison of the inlet pressure derived from the analytical model and the value obtained from the experimental procedure shown a good agreement. Optimization algorithms were applied to generate the ideal die shape. The objective is to minimize the power consumed in the extrusion process, while maintaining maximum strength for the extrudates. It is concluded from the study that the model and the optimization procedure developed for the model can be used in extrusion studies of other powdered materials.
Stepper Motor Driven Four-Bar: Dynamic Modeling and Synthesis
Authors: Wang Sern-Hong , Pisano Albert P. 
Published: February 2021

Abstract
This paper presents the dynamic modeling and synthesis of a four-bar mechanism that is driven by a four-phase, variable-reluctance stepper motor. Dynamic models of both the mechanism and the motor are derived and subsequently combined in order to numerically determine the system dynamic response. In the stepper motor model, full circuit equations are derived for each of 8 stator poles, with full expressions for armature self- and mutual-inductances, as well as developed motor torque. The stepper motor model admits arbitrary input pulse trains, and includes both coil resistance and inductance. A set of five, simultaneous, nonlinear, second-order ordinary differential equations is analytically derived and numerically solved to determine stepper response. In the four-bar mechanism model, three dynamical properties (primary effective inertia, secondary effective inertia, and gravitational disturbance torque) are derived using a Lagrangian approach, and utilized to determine the dynamic suitability of candidate four-bars for three-position, rigid body guidance. Three candidate four-bar mechanisms are synthesized, and their dynamic response (when coupled to the variable-reluctance stepper motor) is compared. It is shown that an engineering trade-off exists between parallelogram and crank-rocker four-bars, in which the former may possess lower primary effective inertia, but the latter may possess lower gravitational disturbance torque.
A Virtual Corporation: An Interdisciplinary and Collaborative Undergraduate Design Experience
Authors: Howell Steve , Harrington Tim , Larson Debra , Collier Ken , Hatfield Jerry 
Published: February 2021

Abstract
Engineering industries are calling for graduates that have a breadth of skills including design and analysis skills, teaming skills and “soft skills” (i.e., project management, concept value analysis, communication, cross-disciplinary understanding, etc.) Furthermore, many American industries are implementing “virtual project work teams”, where expert teams work concurrently in several remote locations, sharing design information and data electronically.
Northern Arizona University’s College of Engineering and Technology is implementing an innovative, four-year, sequence of classes called the Path to Synthesis. The sophomore and junior courses in the Path to Synthesis program are team-taught industry simulations which use collaborative product design to not only develop design skills, teamwork skills, and soft engineering skills, but to also encourage the use of state of the art design methods and professional software tools. During the Fall 1995 semester, a “virtual team” paradigm was introduced into these two classes. NAU students worked with “expert” teams at other institutions to collaboratively complete a major design project. Students used modern high speed electronic media to communicate design ideas, share electronic data, and complete a project which required expertise from student teams dispersed across a wide geographic area.
This paper describes the piloted junior and sophomore level Path to Synthesis courses, and how geographically distributed teams located in Flagstaff, Tempe, and San Francisco collaborated on different aspects of an industrial simulation. This collaborative effort required the use of modern high speed electronic networks for communication, live two way video interaction, and transfer of graphic and CAD data.
Design of Mobile Temperature Monitor System for Autobrazer Baseline Calibration
Authors: Agba Emmanuel I. , Jones E. William , Penaherrera A. Simon , Thrift Bruce 
Published: February 2021

Abstract
The production of heat exchanger coils involves the brazing of return tubes and hairpins to complete the refrigeration circuit. The knowledge of the temperature distribution within an autobrazer is essential for the control of process variables such as burner alignment, gas/flux mixture and conveyor speed. This paper presents the design of a mobile temperature monitor system to measure temperature distributions for the proces s control of an autobrazer. The physical characteristics of the monitoring system in the area of temperature transducer locations simulate closely the actual characteristics of the brazing process. By comparing a measured temperature distribution with a known optimal distribution, the process variables can be adjusted either manually or automatically to affect the process for maximum brazing efficiency. Presently, process variables are adjusted manually and often these adjustments are not repeatable, resulting in high percentage of production coil rejects and subsequent rework.
Design Reasoning Using Plastic Injection Molding Primary Features
Authors: Wood Stephen L. 
Published: February 2021

Abstract
The conceptual design of industrial components requires the engineer to be knowledgeable and competent in designing with features. Basic design features are the primary building blocks of designers: mechanical engineers, industrial engineers, material processing engineers, and tooling specialists. Each feature is specifically used to satisfy an intended function by the individual designer. How the features are used is based upon the experience of the designer and the potential of various features to satisfy specific functions.
This paper develops the primary features used by designers in the injection plastic molding domain, according to their functional properties. The analysis of a part’s functions satisfied by various features, along with the frequency of use, gives an overview of the most pertinent aspects of feature based design. The next generation CAD systems should incorporate design reasoning as a part of the design process algorithms and the capacity to analyze the functional aspects of each feature.
What Are Feature Interactions?
Authors: Regli William C. , Pratt Michael J. 
Published: February 2021

Abstract
Manufacturing features and their interactions have become areas of research scrutiny in recent years. It is widely accepted that intelligent reasoning about interactions among features is a critical element in the development of systems for automated manufacturing. Conversely, however, there has not emerged any general consensus as to what features are, how they are defined, and what it means when one says that features interact.
This paper attempts to focus and refine what is meant by the term feature interaction and outline precisely how interactions can affect automated feature recognition and manufacturing planning. It is our belief that, by establishing a conceptual common ground with regard to these concepts, the research community will be better able to assess how to effectively address the problems that they present.
Reconfigurable Feature Recognition for an Adaptable, Maintainable CAD/CAPP Integration
Authors: Gaines Daniel M. , Castaño Fernando , Hayes Caroline C. 
Published: February 2021

Abstract
This paper presents MEDIATOR, a feature recognition system which is designed to be maintainable and extensible to families of related manufacturing processes. A problem in many feature recognition systems is that they are difficult to maintain. One of the reasons may be because they depend on use of a library of feature-types which are difficult to update when the manufacturing processes change due to changes in the manufacturing equipment. The approach taken by MEDIATOR is based on the idea that the properties of the manufacturing equipment are what enable manufacturable shapes to be produced in a part. MEDIATOR’S method for identifying features uses a description of the manufacturing equipment to simultaneously identify manufacturable volumes (i.e. features) and methods for manufacturing those volumes. Maintenance of the system is simplified because only the description of the equipment needs to be updated in order to update the features identified by the system.
Part to Art
Authors: Sinha Sarvajit S. , Seneviratne Pradeep 
Published: February 2021

Abstract
We posit that free-form design of 3D shapes is far easier when done with a physical medium such as clay than on a 2D computer screen. To this end, we have built a Computer Aided Reverse Engineering system called Surfacer which allows conversion of three-dimensional measurements of the physical prototype into NURBS surfaces that can be manipulated by most Computer Aided Design and Manufacturing systems. The system’s interface has been made simple enough to be mastered by anyone, and the software provides a number of mathematical algorithms that simplify the task of converting 3D data into surfaces. This software and its algorithms are the focus of this paper.
Computing Boolean Combinations of Solids Composed of Free-Form Surfaces
Authors: Krishnan Shankar , Manocha Dinesh 
Published: February 2021

Abstract
We present efficient and accurate algorithms for Boolean combinations of solids composed of sculptured models. The surface of each solid is represented as a collection of trimmed and untrimmed spline surfaces and a connectivity graph. Based on algorithms for trapezoidation of polygons, partitioning of polygons using polygonal chains, surface intersection of high degree spline surfaces and ray-shooting, the boundaries of the resulting solids and its connectivity graph after the Boolean operation are computed. The algorithm has been implemented and its performance measured on a number of industrial models.
Kinematics-Based Geometric Design of Sculptured Surfaces
Authors: Ge Q. J. , Kang Donglai 
Published: February 2021

Abstract
Current practice in CAD/CAM separates the process of geometric shape design from that of CMC (Computer Numerically Controlled) tool path generation. Although successful for 3-axis machining, this strategy is not as effective for 5-axis machining of sculptured surfaces due to the difficulty in generating accurate and gouge-free 5-axis tool paths from the CAD models. This paper presents a framework for a new, kinematics-based methodology for geometric modeling that integrates sculptured-surface design with too-path generation for 5-axis CMC machining. In particular, sculptured surfaces are represented directly in terms of rational Bézier and B-spline motions of the cutting tool. The proposed framework brings together the fields of Kinematics and Computer Aided Geometric Design as well as the recent results in Computer Aided Motion Synthesis and Swept Volume Modeling and provides a basis for concurrent geometric shape design and manufacture.
Machining Algebra for Mapping Volumes to Machining Operations
Authors: Shirur Arvind , Shah Jami J. 
Published: February 2021

Abstract
This paper presents geometric models for representing machining operations. The characteristic shapes produced by machining operations are represented in a uniform (canonical) way for all machining operations as the resultant to two types of tool-workpiece interactions. Each interaction is characterized by a type of sweep operator. The directors of these sweep operations are derived from cutting and feed motion directions. The profiles used in the sweeps are defined in terms of geometric entities and constraints based on tool geometry and tool-workpiece interaction. Most conventional machining processes can be represented using the proposed model (process-to-volume mapping). Inverse operators are also defined for mapping volumes to processes; the inverse operators can be used in selecting potential machining processes for removing given volumes. Thus, representation of machining knowledge is process-based not feature-based, which overcomes the problem of dealing with new feature shapes that are not predefined in the process selector.
Design by Word and Deed
Authors: Fukuda Shuichi 
Published: February 2021

Abstract
It is becoming more and more important to consider how we should integrate our knowledge of skills into design, if we really wish to integrate design and manufacturing, because skills play very important roles in manufacturing. Although there are many design systems avaible, most of them deal only with the symbolic representation of our knowledge and even such medias as TV, video, etc which are considered to be good for skill representation are still in most cases one way from a teacher to a student. To really learn a skill, feedback from a student to a teacher should be established and more interactiveness secured.
We developed a prototype system with the simple example of learning the skill of penmanship for the purpose of clarifying the problems of skill representation and with the hope of integrating skill knowledge into design in the future.
Kitchen Layout Design in Virtual Environments
Authors: Yamamura Akira , Hatanaka Tomoyuki , Nomura Junji 
Published: February 2021

Abstract
This report is a description of our Virtual Reality (VR) technology application, a VR-supported kitchen layout design system. This VR system was developed on personal computers and has made it possible to achieve hardware cost reduction and a user-friendly interface. With the VR system, customers can have a pseudo-experience of their “virtual kitchen” and modify the design of the kitchen. This system helps our customers to make decisions when designing the layout of their new kitchen by giving them a good idea of their potential purchase. The VR system has been in practical use in Matsushita’s showrooms since 1994. In the future, we plan to put the VR system on the Internet. The VR system will also play an important role in user interface in the House Design Advisory System. This system, which we are currently developing, will give advice on house design, as well as on kitchen layout design, according to the customers’ diversified lifestyles.
An Integrated Product and Process Data Model Using Step
Authors: Ghodous Parisa , Vandorpe Denis 
Published: February 2021

Abstract
The integration in computer integrated manufacturing systems (CIMs) plays a significant role in improving the quality and productivity. To achieve this objective, a uniform product and process representation and an effective, comprehensive and reliable data exchange mechanism are required. Recent works on product data integration have led to STEP (international Standard for Exchange of Product data models). In this paper, we define a model which integrates the STEP product data models with process data models. The idea of classification of STEP product data models is used to classify the process data models. Examples from mechanical industries are included to demonstrate the features of this model.
The Green Browser: An Information Sharing Tool for Product Life Cycle Design
Authors: Kurakawa Kei , Kiriyama Takashi , Baba Yasunori , Kobayashi Hideki , Umeda Yasushi , Tomiyama Tetsuo 
Published: February 2021

Abstract
This paper presents the concept and implementation of the Green Browser, which enables designers and consumers to share environmental information. We propose the conceptual scheme of the Green Browser called green life cycle model. This model is intended to represent the product’s environmental impacts over the stages of raw materials, use, recycling, and disposal. The Green Browser has been implemented using WWW and MOO to be able to deal with the strategy model, which is the key element of the green life cycle model. A case study on building the strategy model of refrigerator is presented to illustrate the strategy model.
Quantified Relations: A Class of Predicate Logic Design Constraints Among Sets of Manufacturing, Operating, and Other Variations
Authors: Finch William W. , Ward Allen C. 
Published: February 2021

Abstract
This paper addresses a class of engineering design problems in which multiple sources of variations affect a product’s design, manufacture, and performance. Examples of these sources include uncertainty in nominal dimensions, variations in manufacture, changing environmental or operating conditions, and operator adjustments. Quantified relations (QR’s) are defined as a class of predicate logic expressions representing constraints between sets of design variations. Within QR’s, each variable’s quantifier and the order of quantification express a physical system’s causal relationships. This paper also presents an algorithm which propagates intervals through QR’s involving continuous, monotonic equations. Causal relationships between variables in engineering systems are discussed, and a tabular representation for them is presented. This work aims to broaden the application of automated constraint satisfaction algorithms, shortening design cycles for this class of problem by reducing modeling, and possibly computing effort. It seems to subsume Ward’s prior work on the Label Interval Calculus, extending the approach to a wider range of engineering design problems.