bluuebunny/crossref_metadata_2025_split huggingface dataset:
Models of Visual Thinking by Novice Designers
Authors: Radcliffe David F. , Lee Tat Y. 
Published: April 2021

Abstract
Visual thinking is the creative process by which spatial, numerical and descriptive information is integrated to realize a design idea. A series of experiments have been conducted in which the role of freehand sketching in the design work of novice engineering designers and industrial designers was examined. Three types of sketches, functional, geometric and pictorial, can be identified, each related to the stage of concept development. An adequate sketching technique is essential for the smooth flow of design ideas during the formative stages of a design. Based upon these experimental observations, a model of the process of visual thinking is proposed. In it, sketching forms an interface and potential barrier between the cognitive processes and the physical domain. This barrier can be biased towards either the cognitive or the physical domain, resulting in two different types of impediment to idea development.
A Cognitive Approach to the Analysis of Design Processes
Authors: Takeda Hideaki , Hamada Susumu , Tomiyama Tetsuo , Yoshikawa Hiroyuki 
Published: April 2021

Abstract
The scientific analysis of design is indispensable in order to establish a rich and useful design theory. Accomplishing this, we propose a practical method to investigate design named design experiment and methods to analyze its results. Since the design experiment is performed mainly with the protocol analysis method, We start from discussing the experimental method in comparison to psychological experiments. Furthermore we introduce a new method using a CAD-like system which can record drawing processes precisely. We analyze the protocol data in two ways. One is the analysis by extraction of knowledge. Using this we can clarify how knowledge is used and what knowledge is needed in design processes. The other is based on the cognitive approach. Protocol data is transformed into the semantic network of concepts which is used as the network in the connectionist paradigm. We can identify what the designer pays attention to and how it is changing in design processes by regarding the activations of nodes as the intensity of the designer’s attention.
The Information Requests of Mechanical Design Engineers
Authors: Kuffner Tom A. , Ullman David G. 
Published: April 2021

Abstract
Design documentation does not typically include all of the information sought by mechanical design engineers. This paper reports on a study of practicing engineers making modifications to existing designs. Particular attention is paid to the design information required to answer questions about the design and to verify or refute conjectures about the design. A taxonomy of the questions asked by the designers in this study and the conjectures they formed is presented. It is proposed that an intelligent CAD system be developed to capture, structure, and re-play this information.
Design History Knowledge Representation and its Basic Computer Implementation
Authors: Chen Aihua , McGinnis Brian , Ullman David G. , Dietterich Thomas G. 
Published: April 2021

Abstract
This paper gives an introduction to the implementation of a Mechanical Design History. This history is a record of the constraints developed and decisions made in the evolution of a product from initial specification to final, detailed design. This history allows design, management, and manufacturing personnel to query not only the final drawings representing the design, but also the rationale behind each object in the design.
Learning to Be Skeptical in Engineering Design: A Backpropagation Search Algorithm
Authors: Kott Alexander 
Published: April 2021

Abstract
A human designer becomes skeptical about a particular design direction when his/her attempts to pursue that direction fail. Can we model this strategy in an automated problem solver? This paper describes BP* — an algorithm that attempts to model this strategy. BP* is a best-first algorithm with an A*-like heuristic evaluation function. To model the dynamic skepticism of a human designer, BP* uses the backpropagation mechanism. It dynamically penalizes the parent design state when its children fail to realize the “goodness” promised by the parent BP* is admissible in some probabilistic sense. We also discuss an application of the BP* algorithm, a system that automatically “invents” novel conceptual schemes for thermal systems.
Functions, Structures, and Constraints in Conceptual Design
Authors: Kota Sridhar , Ward Allen C. 
Published: April 2021

Abstract
The authors discuss, from quite different perspectives, some commonly held intuitions about design. In particular, Kota presents a functional design methodology and argues that distinctions between functions, constraints, and structures are essential to well organized design processes, which he sees as involving a hierarchical process from conceptual to routine design. Ward disagrees.
Computer-Aided Generation of Function Block Diagrams in a Methodical Design Procedure
Authors: Hundal M. S. , Byrne J. F. 
Published: April 2021

Abstract
A method for generating function block diagrams with an interactive computer program using a functions data base is described. This step follows the generation of the requirements list, given in an earlier paper (Hundal and Byrne, 1989). The program prompts the user for system inputs and outputs, physical functions and their connectivity. Appropriate functions which may be used for realizing the function structure are suggested by the program. After the first function block diagram has been produced, variants can be generated by looking for alternatives for the chosen functions.
Design Relations
Authors: Rinderle James R. , Colburn Eric R. 
Published: April 2021

Abstract
During preliminary design, designers make critical design decisions based on their experiential knowledge of the characteristics of the components that comprise a system. In particular designers understand the inherent relationship between the form a device will take and the behavior it will exhibit and use this knowledge to estimate characteristics of components and thus evaluate a system. Knowledge of these design relations are gained with experience, but even an experienced designer may not understand the design relations for an unfamiliar device. It is therefore useful to obtain this information automatically and provide it directly to the designer to supplement experience.
In this paper we discuss the nature of design relations and show that these relations are inherent in the physics, shaped by the constraints, and dependent upon the context of the design. We describe a method for automatically identifying these relations from a constraint-based model of a device which is based on solving a sequence of constrained optimization problems.
“Knowledge Sifting” for Preliminary Design
Authors: Miller Victor Todd , Nevill Gale E. 
Published: April 2021

Abstract
This article describes the use of a new symbolic reasoning methodology, based on the use of matrix associative memories, in the domain of preliminary design. A candidate preliminary design is first formulated in terms of a symbolic constraint system. The symbolic reasoner can then derive information about free variables based on the constraints in the system. One of the major difficulties with current reasoning methodologies in artificial intelligence is the scalability problem; as a problem increases in size, interactions between the elements hinder the reasoning process. Initial investigation indicates that this new symbolic reasoning system provides a means to avoid some of the complications that AI search and logic techniques have when scaling up to real world problems. Also, the methodology appears applicable to both analysis and direct synthesis tasks.
Automated Modeling to Support Design
Authors: Rinderle James R. , Balasubramaniam L. 
Published: April 2021

Abstract
The need to consider a number of different alternatives at an early stage in design has been well established. It is hypothesized that providing a tool for automatically modeling and analyzing behavior of an artifact would aid the conceptual designer by facilitating the consideration of more varied alternatives. We describe a tool for automatic formulation of dynamic system models from user specified interconnection of components. The underlying methods are based on Bond Graph formalism using causal reasoning to simplify the model. The simplified model is not only more tractable for analysis and simulation but also facilitates inferences about the dominant characteristics of the designed artifact.
Determining Optimal Model Complexity in an Iterative Design Process
Authors: Bell David G. , Taylor Dean L. 
Published: April 2021

Abstract
In design, trade-offs are made between quality, cost and schedule. As the versatility of design tools has increased, so has the difficulty of making these trade-offs. This is especially true when choosing appropriate complexities for analytical and computational models. A fact known to designers and analysts is that more complex models yield more accurate results, but take longer to create and analyze. This paper shows that in an iterative design process there exists an optimal model complexity for each iteration, and alternatively, one optimal for the process as a whole. Quantitative methods for determining these complexities are developed, and three strategies for controlling the design modelling process are contrasted. Dependent on the stopping criteria, the best strategy will either minimize resource expenditure subject to quality requirements, or conversely, will maximize quality subject to resource constraints. These concepts are formalized with a view towards the design theory and methodology research community providing a first step in quantifying model trade-offs. An illustrative shape-optimal design example is shown wherein cost savings up to 84% were achieved. These savings were seen using several standard optimization algorithms. A customized optimization algorithm that incorporates this work should produce even better results.
Knowledge-Based Computer-Aided Design System for Ingot Casting Processes
Authors: Viswanath R. , Jaluria Yogesh 
Published: April 2021

Abstract
Thermal manufacturing processes are typically those in which a material is subjected to a temporal thermal cycle like casting, extrusion and heat treatment of metals and plastics. The complexity of the design process for all these systems stems from the need to simulate complicated heat transfer, fluid flow and phase change phenomena and couple the results with the design rules and knowledge available on the manufacturing processes to obtain satisfactory designs. In this regard, the ability of expert systems to use heuristic reasoning has proved to be a powerful tool in the computer-aided-design of thermal manufacturing systems.
In this paper, the salient features of a knowledge-based system developed for the design of ingot casting process has been outlined. A Prolog based decision making front-end is interfaced with a Fortran based computational engine for rapid design. The results from the heat transfer analysis obtained from the computational module, are coupled to the evaluation module, which checks for satisfaction of the design criteria and violation of the design constraints. The decision making module uses a set of design rules to manipulate the variables until the design specifications are satisfied. Modularity and flexibility are maintained using an object-oriented format. Several interesting design acceleration features like learning from simple mathematical models and design extraction from previous designs are illustrated. The main features of this knowledge-based tool and the savings in time resulting from using these special features are discussed in detail.
Initial Design Strategies for Iterative Design
Authors: Ramachandran Natarajan , Langrana Noshir A. , Steinberg Louis 
Published: April 2021

Abstract
This paper discusses methods to retrieve design(s) from a design library in order to achieve a better initial starting point for the iterative model of the design process. The motivation for doing this is to reduce the extensive analysis time required for many iterative design problems. Starting a design at a favorable initial point should help reduce the number of iterations. Four initial design methods have been investigated varying from a simple non-library method to methods that use designs from a library. To evaluate the effectiveness of these methods, the initial design methods were tested on four example problems. They are, a cantilever beam, a gear-pair, a v-belt and an extruder-die. It was found that the number of iterations reduced approximately as 1/n, where n is the number of stored values in the design library.
Quantification of Operator Perceived Vibrations for a Consumer Product Design
Authors: Sheth Pradip N. , Shupert P. T. 
Published: April 2021

Abstract
The design process for the development of a new line of rear engine riding lawn mowers is described in this paper. In order to optimize the vibration behavior of this product, it was necessary to define a quantitative measure of the operator perception, or the “feel” of the vibrations at the operator/vehicle interfaces, i.e., the steering wheel, the footrests, and the seat. A Goodness of Vibration factor based on frequency weighting was devised for the design process. This quantitative measure in conjunction with the analytical/experimental tools of spectrum analysis, modal analysis, and finite element analysis during the design process are shown to produce a comfort optimized mower system. The Goodness of Vibration factors are shown to constitute a generic process which, in addition to quantifying the operator perception of vibrations, also help guide the product design process because of their direct relationships to the modal behavior of the system and also to the excitation spectra. This generic approach may have applications to the design process for other consumer power equipment, beyond the mower design demonstrated in this paper.
The Comparison of the Reliability of Three Psychometric Scales for Measuring Design Quality
Authors: Hyde Reva Slaughterbeck , Stauffer Larry Allen 
Published: April 2021

Abstract
Three scales for subjectively measuring design quality have been developed. Each scale represents a unique strategy for aiding a person in judging the quality of a solution to a design problem. The scales are compared with respect to how reliable these judgements are over time. The experimental results demonstrate that one of the scales is not reliable but that the other two are reliable.
Subjective Design Evaluation With Multiple Attributes
Authors: Thurston Deborah L. 
Published: April 2021

Abstract
A formal methodology is presented which may be used to evaluate design alternatives in the iterative design/redesign process. Deterministic multiattribute utility analysis is used to compare the overall utility or value of alternative designs as a function of the levels of several performance characteristics of a manufactured system. The evaluation function reflects the designers subjective preferences. Sensitivity analysis provides quantitative information as to how a design should be modified in order to increase its utility to the design decision maker. Improvements in one or more areas or performance and tradeoffs between attributes which would increase desirability of a design most may be quantified. A case study of materials selection and design in the automotive industry is presented. The methodology was applied to 6 automotive companies in the United States and Europe, and results are used to illustrate the steps followed in application.
DIscrepancy of Gear Tooth Allowable Bending Stress Using the Extreme Value Distribution From Different Test Methods
Authors: Hou Chienann A. , Ma Shijun 
Published: April 2021

Abstract
The allowable bending stress Se of a gear tooth is one of the basic factors in gear design. It can be determined by either the pulsating test or the gear-running test. However, some differences exist between the allowable bending stress Se obtained from these different test methods. In this paper, the probability distribution functions corresponding to each test method are analyzed and the expressions for the minimum extreme value distribution are presented. By using numerical integration, Se values from the population of the same tested gear tooth are obtained. Based on this investigation it is shown that the differences in Se obtained from the different test methods are significant. A proposed correction factor associated with the different experimental approaches is also presented.
A Bayesian Estimation of Reliability Measures of Stepwise Exponential Distribution System
Authors: Hu M. H. 
Published: April 2021

Abstract
This paper presents an analysis method for reliability measures of a system with step changes in failure and repair rates. Both failure and repair time have exponential function of time. Such a system is called a stepwise exponential distribution system. This kind of failure process can take place in various equipments. This paper deals with the system having components in series arrangement. Bayesian statistics is used in defining prior and posterior probability density functions of failure and repair rates. These functions provide information for the estimation of reliability measures: 1) failure and repair rates, 2) mean time to failure, 3) mean time to repair, 4) reliability function and 5) availability. A sample problem is given to illustrate the methodology. The Bayesian estimation of the stepwise exponential distribution model is useful in the planning of equipment predictive maintenance.
A Probabilistic Methodology for Random Stress-Strain Curves
Authors: Millwater H. R. , Harren S. V. , Thacker B. H. 
Published: April 2021

Abstract
This paper presents a methodology for analyzing structures with random stress-strain behavior. Uncertainties in the stress-strain curve of a structure are simulated by letting a small number of engineering parameters which describe the stress-strain curve be random. Certain constraints are imposed on the engineering parameters in order to have a physically realizable material. A general procedure to handle correlation among the stress-strain parameters has also been developed.
This methodology has been integrated into the NESSUS (Numerical Evaluation of Stochastic Structures Under Stress) probabilistic structural analysis system. With this system, probabilistic finite element analysis of structures with random stress-strain behavior can be analyzed in an accurate, automated fashion.
An example problem is presented to demonstrate the capabilities of the code. The problem analyzed is that of a pressure vessel fabricated with a material exhibiting random stress-strain behavior.
Estimation of Structural Reliability Under Random Fatigue Conditions
Authors: Baldwin J. D. , Thacker J. G. , Baber T. T. 
Published: April 2021

Abstract
A procedure for determining the reliability of a structural element or machine part is presented. The solution assumes that the stress history in the part can be described by a narrow band, stationary, Gaussian random process and that the fatigue behavior of the part is governed by the classical S-N curve. Endurance limit modifications are discussed and a procedure is presented for determining the mean and standard deviation of the static stresses acting throughout a structure. A numerical example is presented showing the method applied to estimate the fatigue reliability of a power wheelchair frame.
Combined Stress and Resistance Modeling With the Nessus Software System
Authors: Thacker B. H. , Harren S. V. , Millwater H. R. 
Published: April 2021

Abstract
Computing the reliability of structural components with uncertainties in both stress and resistance variables is investigated. The NESSUS™ probabilistic software is used to perform the reliability computations using both Fast Probability Integration (FPI) and Monte Carlo methods. Results are compared for an example reliability analysis using both closed-form expressions and finite elements. The Advanced Mean Value probabilistic algorithm is used and is shown to yield highly accurate results, even for highly nonlinear response functions. The results show clearly the effectiveness of the newly incorporated algorithms available in the NESSUS software for computing structural reliability.
Fatigue Reliability Functions in Semilogarithmic Coordinates
Authors: Avakov Vladimir A. 
Published: April 2021

Abstract
In the previous publication [2], the transformation between fatigue life and strength distribution was established using double-logarithmic coordinate system (lnN-lnS). Here, a similar transformation is established using a semi logarithmic (lnN-S) coordinate system. With the aid of the developed orthogonal relations, lognormal, Weibull and three-parameter logweibull life distributions have been transformed into normal, asymptotic type 1 of smallest value, and three-parameter Weibull strength distributions, respectively. This procedure may be applied to other types of fatigue life distribution.
Computer Simulation and Reliability Analysis of Fatigue Crack Propagation Under Random Loading
Authors: Wu Wen-Fang 
Published: April 2021

Abstract
In order to study the behavior of fatigue crack propagation and fatigue reliability of a structural or mechanical component under random loading, a numerical simulation scheme and other analytical prediction models are proposed in this paper. The paper consists of (1) digital generation of random loading from random process theory; (2) numerical simulation of fatigue crack growth based on fracture mechanics concept; (3) a modified rain-flow cycle counting method for the identification of stress cycles and stress amplitudes; (4) Weibull probability density fit and other statistical analyses for the stress amplitudes as well as the crack growth curves; and (5) probabilistic models for the prediction of fatigue crack growth, fatigue life and fatigue reliability. Some conclusions are drawn at the end of this paper which can be used as references in the design of a structural or mechanical component under random loading.
Fatigue Design of Machine Components Using New Forms of S-N and Mean Stress Diagrams
Authors: Bagci Cemil 
Published: April 2021

Abstract
Article presents continuous forms of S-N and Mean Stress Diagrams for fatigue design of machine and structural components against breakage; and offers data verifying the proposed forms of the diagrams. Two forms of constructing the mean stress diagram — one for the test specimen, one for the critical section of the machine component — are offered. Defects in using conventional forms of the diagrams are removed. Discussions upgrading fatigue strength reduction factors are included. Computer-aided fatigue design applications are discussed. Determining remaining life considering cumulative damage effect using the offered forms of design diagrams is also included. Application examples are given.
Auger Elevator: Failure Modes and Effects Case Study
Authors: Brickman Dennis B. , Barnett Ralph L. 
Published: April 2021

Abstract
A fatal accident occurred when a right angle gear box on an auger elevator disintegrated freeing the outboard end of a rotating PTO shaft. The tractor, acting as a stationary power source, flailed the PTO shaft which then struck and killed a farmer. No similar occurrences have been reported for the nearly 2000 similar units which have been used for over a decade. This paper studies a number of fundamental failure modes in order to determine which failure modes created the accident. Systematic analysis showed that the accident was caused by unusual misuse of the product. Known safety control concepts do not preclude this unforeseeable event.