bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Behavior of Rectangular Plates Under Concentrated Load
Authors: Sturm R. G. , Moore R. L. 
Published: February 2021

Abstract
This paper presents a summary of the experimental and analytical research on flat plates under concentrated normal loads conducted at the Aluminum Research Laboratories. The experimental work includes tests on a number of different sizes of plates, ranging from 1/8 in. to 1 in. thickness, loaded on spans of from 48 to 384 times the thickness. The effect of the degree of load concentration, types of edge support, and position of the load upon the stresses and deflections have been the principal variables studied. Cases of bending alone, and combined bending and direct stress have been considered. The analytical work refers to the existing general analysis of the flat-plate problem, from which formulas suitable for design purposes have been derived.
The Crank Arrangement of a Nine-Cylinder Engine
Authors: Lewis F. M. , Breault E. E. , Donaldson R. M. 
Published: February 2021

Abstract
The authors discuss the multiplicity of possible crank arrangements for a nine-cylinder engine and devise a means by which certain crank arrangements can be chosen which will meet certain arbitrary requirements of reciprocating and rotating moments. The investigation has been limited to crank arrangements with 40-deg crank intervals.
Vibration Stress Measurements in Strong Centrifugal Fields
Authors: Kearns Charles M. , Guerke Ralph M. 
Published: February 2021

Abstract
Following a brief review of existing methods of measuring vibrational stresses in strong centrifugal fields, the authors discuss the characteristics of carbon-resistance strain gages and indicate their method of use.
These gages may be calibrated statically and used for dynamic measurements with an accuracy of plus or minus ten per cent; and with present cementing technique they can be applied in fields up to 12000 × gravity.
The necessary instruments for use with these pickups are described and several records of aircraft-propeller tip stresses are shown.
Distortion of the Photoelastic Fringe Pattern in an Optically Unbalanced Polariscope
Authors: Mindlin Raymond D. 
Published: February 2021

Abstract
This paper describes the results of an investigation of the effect of inaccuracies in the two quarter-wave plates of a photoelastic polariscope on the configuration of the monochromatic fringe pattern. It is shown that the fringe pattern is distorted to an extent which depends upon the orientations of the axes of principal stress and the difference between the retardations of the two plates.
A Rapid Method for the Determination of Principal Stresses Across Sections of Symmetry From Photoelastic Data
Authors: Frocht M. M. 
Published: February 2021

Abstract
The author discusses: (a) Mesnager’s theorem of isoclinics, (b) the characteristic curve of tangential stresses across a section of symmetry, (c) a formula for the maximum tangential stresses for the case of a central circular hole between fields of pure tension, (d) the slope of the p curve at a point corresponding to a cupic point, (e) recent improvement in the determination of free boundary stresses, and (f) formulas for the position of cupic points for two cases. A new method for the determination of the principal stresses across sections of symmetry from photoelastic data is illustrated with three examples: (1) Bars in tension or compression with central circular holes, (2) grooved beams in bending, and (3) rings or disks with circular central holes subjected to two concentrated diametral loads.
The Fundamentals of Three-Dimensional Photoelasticity
Authors: Hetényi M. 
Published: February 2021

Abstract
The method of three-dimensional photoelasticity is based on the experimental fact that samples of phenolic resins, such as Bakelite, Marblette, and Trolon, when annealed in a loaded condition show a complete preservation of (a) the elastic deformation and (b) the accompanying birefringence produced by the loading at the annealing temperature. After presenting a historical review of the method, the author discusses the current theory of the molecular structure of phenolic resins by which the phenomena observed in the annealing procedure can be explained. Test results are given which prove the elasticity of Bakelite at elevated temperatures. Applications of the method are also discussed.
Feature Validation in a Multiple-View Modeling System
Authors: Dohmen Maurice , de Kraker Klaas Jan , Bronsvoort Willem F. 
Published: February 2021

Abstract
A new approach to specification and maintenance of feature validity conditions in a multiple-view feature modeling system is presented. Each view of a product contains a feature model. Features are specified declaratively in an object-oriented language, using constraints to specify feature validity conditions. Constraints are also used to specify relations between features. Validation of the feature models is done by a constraint manager that integrates different solving techniques. The constraint graph is mapped by the constraint manager onto constraints that are handled by dedicated solvers. If views are consistent, i.e. their feature models represent the same geometry, feature parameters can be changed. Changes are propagated through link constraints between different views.
Neural-Taguchi Method for Robust Design
Authors: Wang Gou-Jen , Tsai Jhy-Cherng , Tzeng Pai-Chung , Chen Tsorng-Chi 
Published: February 2021

Abstract
Neural-Taguchi, a new engineering analysis method that combines the neural-network and the Taguchi techniques for better improvement of engineering design is proposed in this paper. Explicit system model that allows precise prediction and easy optimizing is constructed in terms of a multilayer feedforward neural network. Advantages and good performances of the proposed Neural-Taguchi method are well illustrated by a die cast component analysis problem.
Survey on Use of Virtual Environments in Design and Manufacturing
Authors: Gupta Rakesh 
Published: February 2021

Abstract
This paper surveys the work being done in Virtual Environments (VE) in both design and manufacturing with an emphasis on the industrial use of Virtual Environments. Research and applications are categorized into seven major areas: prototyping and design visualization; verification of design assembly; design creation; concurrent product design and marketing; manufacturing; training and maintenance; and human factors in design. These seven categories are neither mutually exclusive nor collectively exhaustive. For each of these major areas, the paper discusses the issues and the state of the art, emphasizing recent significant advances.
An Integrated Approach to Teaching Mechanism Analysis Using Working Model
Authors: Buffinton Keith W. , Chang Victor W. 
Published: February 2021

Abstract
An approach to engineering education that integrates traditional analytical techniques, modern computational software, and physical hardware has been developed at Bucknell University. This paper describes the implementation of this approach in a juniorlevel required course in mechanism analysis. The content of the course supplements textbook material with computational and experimental laboratory exercises. The computational components of the laboratories are based primarily on the use of the software package Working Model and, to a lesser extent, Pro/JR. Three particular laboratories are described in detail in the paper. The laboratories seek to develop and reinforce the view that textbook analysis techniques and sophisticated computer software are merely tools and only useful if applied intelligently. Moreover, the laboratories emphasize the need for validation and verification in engineering design and analysis. The integrated interactive environment provided in the laboratories not only allows students to quickly see the limits of analytical and computational techniques but also to gain a firsthand understanding of the performance of actual mechanisms.
Rapid Prototyping of Fuzzy Logic Controllers
Authors: Gorman Kevin J. , Rahnamai Kourosh J. 
Published: February 2021

Abstract
The rapid prototyping of fuzzy logic controllers is accomplished by using the tools Matlab, Simulink, Fuzzy Logic Toolkit, and Real-Time Workshop. Device drivers were developed for Simulink for interfacing with DT2801 and DT2821 data acquisition boards. The fuzzy logic inference engine for the Fuzzy Logic Toolkit was modified to allow the systems to work as independent programs and to be downloadable to DSP (Digital Signal Processing) boards. Simulink is used to graphically implement fuzzy logic controllers. The Real-Time Workshop is used to compile blocks from Simulink into C code, then into an independent executable program, both on the PC and a dSpace DSP (Digital Signal Processing) board. Graphical interfaces are created and debugged by using dSPACE’s tools, Cockpit and Trace. By combining these tools, real-time fuzzy logic controllers are developed in laboratory environments.
Impact Analysis of a Dropped Object Using Static Finite Element Software
Authors: Spencer Todd J. , Suchora Daniel H. 
Published: February 2021

Abstract
The purpose of this study was to develop a method to solve impact problems using a static finite element analysis software package. This allows an engineer to approximate the stresses in a body when it is dropped and strikes the ground or supports. This is intended mainly for use when an advanced finite element package that solves dynamic problems is not available.
The method developed in this work was used to predict stresses and strains in a simply supported test beam. The test beam was dropped in the laboratory and experimental strains were recorded. The results of these two methods were then compared, which indicates the validity of this work. This method can be easily applied to more complicated structures.
An Eighteen-Node Solid Element for Thin Plate/Shell Analysis
Authors: Sze K. Y. 
Published: February 2021

Abstract
In this paper, hybrid stress method is employed to formulate stabilization vectors for the uniformly reduced integrated eighteen-node solid elements. The assumed stress is contravariant in nature and is devised based on the strain associated with the commutable zero energy modes of a geometrically regular element. It will be seen that the stabilization vectors can be derived and programmed explicitly without resorting to numerical integration loops. Admissible matrix formulation is employed in evaluating the flexibility matrix and the resulting matrix is diagonal in nature.
Generalization of Classical Modal Analysis
Authors: Ma F. , Lee W. C. 
Published: February 2021

Abstract
The coefficients of a linear nonconservative structure are arbitrary matrices lacking the usual properties of symmetry and definiteness. Classical modal analysis is extended in this paper so as to apply to structures with nonsymmetric coefficients. The extension utilizes equivalence transformations and does not require conversion of the equations of motion to first-order forms. Compared with the state-space approach, the generalized modal analysis can offer substantial reduction in computational effort and ample physical insight.
Application of Two-Step Component Mode Synthesis for System Eigensolutions
Authors: Ramani Anand , Knight Charles E. 
Published: February 2021

Abstract
Component Mode Synthesis (CMS) is a dynamic substructuring technique for approximate eigensolutions of large degree-of-freedom systems divisible into two or more components. System synthesis using component modes results in approximate eigenparameters. The approximation is improved by using more component modes in synthesis. Typically, all component modes up to x times the frequency range of interest are required to assure reasonable accuracy, where x varies from 2 to 10. This paper demonstrates the two-step CMS approach, wherein, the first step involves system synthesis using the minimum number of component modes (x∼1) required to obtain approximate eigenvalues up to a preselected frequency and the second step uses additional component modes in a convergence scheme operating on the system eigenparameters calculated in the first step. Results of studies on spring-mass systems, beam and plate models, and a refrigeration compressor assembly show that the two-step method provides the analyst some insight into the convergence and accuracy of the eigenparameters without resolving the system over and over with more component modes. The method is also efficient in terms of solution time, when compared to conventional CMS using the Jacobi method and the subspace-iteration method.
Geometry Reconstruction of Vectorized Drawings Consisting of Orthographic Views
Authors: Das Atish K. , Langrana Noshir A. 
Published: February 2021

Abstract
The benefits of the existing CAD systems are not available to a large number of engineering drawings which were created on paper using conventional drafting methods. There is a need for an automated system which will convert the scanned images of these drawings into a format recognizable by a CAD system. One of the main components of such a system is the vectorization (raster-to-vector) system which converts the binary image of the scanned drawing into a set of straight line segments, arcs, and circles. The accuracy of the vectorized output in terms of the location and size of the various entities is very important if it is to be used for further processing. This paper describes a system which rectifies errors in the vectorized output using a constraint-based approach based on the principles of variational geometry. The system considers drawings consisting of three orthographic views. The dimension sets present in the drawing and the logical relationship existing between the views are recognized and interpreted to obtain a set constraints governing the geometry of the object. The set of constraint equations are then numerically solved to obtain the exact coordinates of the points used to describe the geometry.
Two-Stage Algorithm for Rapid Determination of the Bending Sequence in Sheet Metal Products
Authors: Radin B. , Shpitalni M. , Hartman I. 
Published: February 2021

Abstract
This paper presents an algorithm for solving the complex and critical problem of bending sequence in sheet metal manufacturing. Finding the bending sequence and required tool assignment presents a large combinatorial problem which is impossible to solve optimally for practical applications within a reasonable period of time.
The paper presents a two-stage algorithm. The first stage finds a feasible solution based upon collision avoidance heuristics. The second stage rapidly seeks an alternative feasible sequence with a lower cost without exceeding time limitations. The algorithm is very practical because it reaches a low-cost solution quickly within computer memory limitations.
In this paper, the problem is defined, the approach is presented formally, and finally, the power of the algorithm is demonstrated by solving bending sequences for real products.
A New Approach to CE by Multifunctional Mapping Process
Authors: Wang Qingwen , Zhou Ji , Xiao Renbin , Yu Jun 
Published: February 2021

Abstract
This paper takes Concurrent Engineering (CE) and Multifunctional Designs (MFD) as mapping and inverse mapping process between every agent’s functional space and physical space. The mapping and inverse mapping algorithms are introduced and an example of shaft design is given to test the algorithms. Based on the new approach, some problems of CE such as negotiation and design tasks management can be dealt with more easily due to inverse mapping process.
Simulation of Multibody Dynamics in Autocad
Authors: Lin Shih-Tin , Lin Jhy-Hong 
Published: February 2021

Abstract
A general purpose multibody dynamics algorithm is written and merged into AutoCAD. This merger creates a user friendly environment for the simulation of multibody mechanical systems such as robot manipulators. Users can prepare input data of the dynamic code easily after creating an AutoCAD drawing of the multibody system. After the dynamic analysis is complete, the results can be easily used to produce animation slides in AutoCAD. The multibody dynamics algorithm uses a recursive variational formulation. This formulation has been proven to be computationally more efficient.
Integration of Knowledge-Base and CAD System for the Machinery Layout Design of Ships
Authors: Lee J. K. , Lee K. H. , Park N. S. , Jang Y. U. , Bae J. Y. , Shim H. S. 
Published: February 2021

Abstract
The current trend of CAD system is to make the system intelligent. CAD systems need to be intelligent in the sense that they must be able to use knowledge to achieve the designer’s goal. In the early stages of ship design, more experienced and higher level knowledge is required rather than that of detail design. The existing CAD systems have several limitations in terms of satisfying the requirements of real design. Accordingly, a more powerful and capable CAD system is required to support the activities in the early stage of design. Recently the application of expert systems has been considered as a tool for extending the capability of existing CAD systems. In this paper, we present an approach to implement a practical knowledge-based system for the machinery layout design of a ship engine room. The knowledge-base is implemented and verified in the actual CAD environment of a ship engine room, named MADES, which we develop in this study. The approaches presented in this paper provide a practical example of a knowledge-based system for complex design problems, and can also provide guidance on implementing an integrated design expert system that extends the capability of existing CAD systems.
Optimal Rough Cutting Tool Path on Cross Sections of Sculptured Surface
Authors: Lee Hi K. , Yang Gyun E. , Ryuh Beom S. , Park Se H. 
Published: February 2021

Abstract
The optimal tool path for NC milling of a sculptured surface is given on cross sections of the surface, which extends the application of contour tool path from 2 dimensional milling to 3-axis and 5-axis milling. The cutting speed in rough cutting is the main objective of the optimal path. The contour tool path on cross sections of the surface can generate the rough cutting path in high speed without excessive cutting force, chatter and heavy wear of the cutting tool. Also, the path can be expanded to 3 -axis and 5-axis milling for machining of complicated surfaces.
Heuristic Modification of Cutting Conditions Using Neural Network
Authors: Park Byoung T. , Park Myon W. 
Published: February 2021

Abstract
Process planners usually need to make modifications to recommended cutting conditions obtained from machining data handbooks in order to satisfy requirements for individual operation. However, because these modifications are based on the experience of process planners, the systematization of this procedure requires experience-oriented methods. In this paper, a new procedure and technology that allows the implementation of an intelligent system for the milling process is proposed. A Mill-COPS based on such a proposal has been developed. Neural network methodology is introduced to identify mathematical models for optimizing the cutting conditions in this system. The results are demonstrated with respect to given cutting conditions.
Direct Differentiation Methods for the Design Sensitivity of Multibody Dynamic Systems
Authors: Serban Radu , Freeman Jeffrey S. 
Published: February 2021

Abstract
Methods for formulating the first-order design sensitivity of multibody systems by direct differentiation are presented. These types of systems, when formulated by Euler-Lagrange techniques, are representable using differential-algebraic equations (DAE). The sensitivity analysis methods presented also result in systems of DAE’s which can be solved using standard techniques. Problems with previous direct differentiation sensitivity analysis derivations are highlighted, since they do not result in valid systems of DAE’s. This is shown using the simple pendulum example, which can be analyzed in both ODE and DAE form. Finally, a slider-crank example is used to show application of the method to mechanism analysis.
Hider: A Methodology for Early-Stage Exploration of Design Space
Authors: Reddy Sudhakar Y. 
Published: February 2021

Abstract
This paper describes HIDER, a methodology that enables detailed simulation models to be used during the early stages of system design. HIDER uses a machine learning approach to form abstract models from the detailed models. The abstract models are used for multiple-objective optimization to obtain sets of non-dominated designs. The tradeoffs between design and performance attributes in the non-dominated sets are used to interactively refine the design space. A prototype design tool has been developed to assist the designer in easily forming abstract models, flexibly defining optimization problems, and interactively exploring and refining the design space. To demonstrate the practical applicability of this approach, the paper presents results from the application of HIDER to the system-level design of a wheel loader. In this demonstration, complex simulation models for cycle time evaluation and stability analysis are used together for early-stage exploration of design space.
Formulation and Implementation of Nonholonomic Constraints in the Analysis of Multibody Systems Using Joint Coordinates
Authors: Balling Claus 
Published: February 2021

Abstract
A general formulation for analysis of spatial multibody systems subjected to nonholonomic constraints is presented. Nonholonomic constraints are usually formulated in Cartesian coordinates constraining the relative velocity or acceleration between some (fixed or moving) points on two bodies in mutual interaction or a point on one body with respect to ground.
The formulation involves a specific type of nonholonomic constraint (rolling disk on a surface) in terms of joint coordinates and perform the implementation in a general purpose program.
CAD and Optimization of Spur and Helical Gear Sets
Authors: Metwalli Sayed M. , El Danaf Ehab A. 
Published: February 2021

Abstract
The present work is an application of Computer Aided Design and optimization techniques to solve the problem of designing a pair of gears. The CAD programs have the initial freedom to change the design variables: the module, the number of teeth, the face width, and the material through a data base display, and a full detailed design stage that applies the AGMA bending and contact number checking criteria, and the bending fatigue strength and the surface endurance strength criteria. Other programs are also linked to optimize spur gears under the objective of minimizing the volume. The design vector is taken to be the module, the number of teeth, and the face width, with the interaction between bending and contact stress constraints. These programs were utilized to study the behavior of the optimum parameters for a full range of cases. Charts of the optimum results are plotted. For optimizing helical gears, the design vector is taken as the module, the number of teeth, the face width, and the helix angle. A comparison is made between values of the objective function and optimum parameters for spur and helical gears for a wide range of cases. A comparison is also made of the results with other previous works of optimization and proved that the approach presented here gives better optimum results for the same loading case.