bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Method of Analyzing Creep Data
Authors: Sturm R. G. , Dumont C. , Howell F. M. 
Published: February 2021

Abstract
The authors present a method for studying creep data which has been in use for the past four years at the Aluminum Research Laboratories. It is shown by graphs that a linear relationship exists between the logarithm of the creep and the logarithm of the elapsed time for a given material at ordinary room temperatures and constant stress. This is established by the fact that the logarithmic curves for a given material at a constant temperature have a constant slope for a relatively wide range of stresses. It is pointed out that the relative effect of cold working upon the strength of different metals seems to explain the behavior of the metals when failure is impending, this being indicated by the tendency of the logarithmic creep-time curves to depart from straight lines. The authors conclude that when homologous stresses based on the tensile strength of the material are considered, different materials exhibit very similar characteristics in the relationship between the homologous stress and the logarithm of the time necessary for a given amount of creep to occur.
Increasing the Fatigue Strength of Press-Fitted Axle Assemblies by Surface Rolling
Authors: Horger O. J. , Maulbetsch J. L. 
Published: February 2021

Abstract
This paper presents test data on 2-in. axles showing how fatigue strength in reversed bending is reduced to between one half to one third its value by the mere presence of a press-fitted member and how such a press-fit assembly may be made more than twice as strong by surface rolling the axle at the press-fit seat. Further tests are given to show that increased strength obtained by surface rolling is due principally to strain hardening of the material at the surface of the axle. The weakening action of press fits is due to large stress concentration and rubbing corrosion localized near the ends of the pressed-on hub, and in this respect surface rolling produces a layer of material having a resistance which is considerably increased in the region of this local weakness.
Additional data are presented to show that plain cylindrical specimens of the usual 0.3-in. diameter give 10 to 15 per cent increased fatigue strength over that given by specimens about 1 in. in diameter; and to show that there should be no difference in fatigue strength between a cantilever- and a beam-type specimen of the same diameter and of the same steel.
Bending of an Infinite Beam on an Elastic Foundation
Authors: Biot M. A. 
Published: February 2021

Abstract
The elementary theory of the bending of a beam on an elastic foundation is based on the assumption that the beam is resting on a continuously distributed set of springs the stiffness of which is defined by a “modulus of the foundation” k. Very seldom, however, does it happen that the foundation is actually constituted this way.
Generally, the foundation is an elastic continuum characterized by two elastic constants, a modulus of elasticity E, and a Poisson ratio ν. The problem of the bending of a beam resting on such a foundation has been approached already by various authors.
The author attempts to give in this paper a more exact solution of one aspect of this problem, i.e., the case of an infinite beam under a concentrated load. A notable difference exists between the results obtained from the assumptions of a two-dimensional foundation and of a three-dimensional foundation.
Bending-moment and deflection curves for the two-dimensional case are shown in Figs. 4 and 5. A value of the modulus k is given for both cases by which the elementary theory can be used and leads to results which are fairly acceptable. These values depend on the stiffness of the beam and on the elasticity of the foundation.
Cantilever Plate With Concentrated Edge Load
Authors: Holl D. L. 
Published: February 2021

Abstract
The author gives, by the method of finite differences, an approximate solution of the problem of a finite length of a cantilever plate which bears a concentrated load at the longitudinal free edge. All the boundary conditions are taken into account, and the plate action is determined approximately at all points of the plate. The author points out that a secondary maximum transverse stress occurs at the clamped edge nearest the loading point, and that the longitudinal stress is greatest directly under the loading point.
Design of Members Subjected to Creep at High Temperatures
Authors: Marin Joseph 
Published: February 2021

Abstract
The author discusses the stresses in machine and structural members subjected to high temperatures as determined by theories advanced by Bailey and St. Venant, the latter of which has been stated by Soderberg. He compares the results obtained by the application of these two theories, and shows that the results from each theory agree equally well with test results. Finally, various cases of thin tubes and the problem of the thick cylinder are considered, using each theory.
The Calculation of Maximum Deflection, Moment, and Shear for Uniformly Loaded Rectangular Plate With Clamped Edges
Authors: Wojtaszak I. A. 
Published: February 2021

Abstract
The problem of the uniformly loaded rectangular plate with four clamped edges has been solved by H. Hencky and independently by J. Boobnoff. Hencky made refined calculations only for the case of a square plate while Boobnoff made precise calculations for several ratios of the sides of the plate. This article gives the results of calculations for maximum deflection, moment, and shear for several ratios of the sides of the plate, using Hencky’s equations. Curves are drawn with the coefficients, used in defining these maximum quantities, as ordinates and the ratios of the sides of the plate as abscissas.
Correlation of Creep and Relaxation Properties of Copper
Authors: Davenport C. C. 
Published: February 2021

Abstract
Creep tests as well as relaxation tests have been carried out in torsion on copper tubes which permit a verification of the various theories proposed for a deduction of the relaxation characteristics from creep tests alone. It was found that the actually observed relaxation time lies between the two values calculated for this quantity on the basis of the strain-hardening and the time-hardening theories.
Revisiting the Lattice Boltzmann Method Through a Nonequilibrium Thermodynamics Perspective
Authors: Jonnalagadda Anirudh , Sharma Atul , Agrawal Amit 
Published: February 2021

Abstract
In this paper, we incorporate a nonequilibrium thermodynamics perspective that is consistent with the Onsager reciprocity principle into the lattice Boltzmann framework to propose a novel regularized lattice Boltzmann formulation for modeling the Navier–Stokes–Fourier equations. The new method is applied to one-dimensional (1D) isothermal situations wherein the advantages of incorporating such a nonequilibrium perspective can be explicitly appreciated. In such situations, the nonequilibrium contribution of the lattice populations obtained by the new method completely vanishes, and the lattice update is entirely reduced to evaluating the equilibrium distribution function. Such a counterintuitive 1D mesoscopic description is not obtained in any other existing lattice Boltzmann scheme. We therefore numerically test the proposed formulation on two complex problems, namely, shockwave and nonlinear wave propagation, and compare results with analytical results along with six existing lattice Boltzmann schemes; it is found that the new method indeed yields results that are more stable and accurate. These results highlight the potency of the nonequilibrium thermodynamics-based approach for obtaining accurate and stable lattice Boltzmann computations, and provide new insights into established lattice Boltzmann simulation methods.
Effect of Surface Roughness on Fluid Flow and Heat Transfer Characteristics of Lattice Brick Setting in Tunnel Kilns
Authors: Almesri Issa F. , Alrahmani Mosab A. , Almutairi Jaber H. , Abou-Ziyan Hosny Z. 
Published: February 2021

AbstractThis paper presents the effect of brick and kiln wall roughness on the fluid flow, pressure drop, and convection and radiation heat transfer in tunnel kilns. The surface roughness of 0–4 mm is investigated for bricks and tunnel boundary. Another wall roughness of 10 mm is considered to explore the effect of significant defects in the tunnel boundary. The study is conducted using a three-dimensional computational fluid dynamics (CFD) model based on the finite volume method with the k – ω turbulence model. The convective heat transfer coefficients enhance by 45% and 97%, and the pressure drop increases by 25.1% and 80.4% as the brick roughness is increased from 0 to 1 mm and 0 to 4 mm, respectively. The ratio of heat transfer rate to pumping power reaches its maximum at a brick roughness of 2 mm. These results provide essential knowledge about the acceptable range of brick roughness for manufacturers. As the tunnel boundary roughness is increased from 0 to 1 and 0 to 10 mm, the heat transfer rates increase by 1.34% and 3.88%, while the pressure drops increase by 7.5% and 18.2%, respectively. These results are supportive of scheduling the maintenance of tunnel kilns’ interior structure. Moreover, the enhancement of the radiation heat transfer depends on the brick emissivity and the area ratio of rough to smooth surfaces.
A Modeling and Design Method for Flexible Manufacturing System Controller Software
Authors: Xirouchakis Paul C. 
Published: February 2021

Abstract
“Entity-life modeling” (ELM) is a general method for the modeling and design of concurrent software. One area where it can applied is for the control software for flexible manufacturing systems (FMS). The application of ELM allows the integration and overall control of the operation of the numerically controlled machinery, the material transportation and storage facilities into automated factories within the context of computer integrated manufacturing (CIM). The development of flexible manufacturing has been hampered by the lack of such a general approach to FMS software design.
ELM is based on the principle that processes and objects in the software are patterned after concurrent “threads of events” and objects in the problem domain. A job in an FMS represents such a thread with events such as “pick from storage”, “place on stand”, etc., which all occur sequentially and with certain time intervals. Several job threads are in progress simultaneously as different jobs are being processed. In the software, a thread of events is represented by a process, such as an Ada task. The direct coupling between the analysis and an efficient control-system software implementation is an advantage over other analysis models, such as Petri nets.
A simple FMS is used as an example. It consists of a storage facility and a number of numerically controlled workstations. A conveyor belt is used for the transportation of parts between storage and workstations and between workstations.
Extracting Grip Areas From Feature Information
Authors: van Holland Winfried , Bronsvoort Willem F. 
Published: February 2021

Abstract
In flexible assembly, an important problem is grip planning, in which possible grips on a component are determined. The first step in determining these grips is to find all finger domains on the component, areas where a gripper finger can be positioned.
Finger domains are commonly computed from geometric information of the component only. One way to do this, is to find so-called non-free regions, areas where the finger cannot be positioned, using the Expanded Face Solid (EFS) method. This method creates for every face in the model an envelope volume depending on the finger geometry. The areas where the model intersects the envelope volumes are the non-free regions. The EFS method must be executed for every face in the model, and is therefore time consuming.
We present a new method to retrieve the finger domains, minimizing the number of faces that have to be investigated with the EFS method, by making use of feature information stored in the product model of the component. Not only design features, but also assembly features storing assembly-specific information are used for this purpose. We distinguish two types of assembly features: connection and handling features, storing information on connections between components, respectively information for handling a component. In our method, information from these features is exploited in a number of steps to compute the finger domains.
The results presented in this paper show that the computation times of finding finger domains using our method are considerably lower compared with using the EFS method.
Automated Reuse of Solutions in Manufacturing Process Planning Through a Case-Based Approach
Authors: Marefat M. , Britanik J. 
Published: February 2021

Abstract
This research focuses on the development of an object-oriented case-based process planner which combines the advantages of the variant and generative approaches to process planning. The case-based process planner operates on general 3D prismatic parts, represented by a collection of features (eg: slots, pockets, holes, etc.). Each feature subplan is developed by the case-based planner. Then the feature subplans are combined into the global process plan for the part via a hierarchical plan merging mechanism. Abstracted feature subplans correspond to cases, which are used in subsequent planning operations to solve new problems. The abstracting and storing of feature subplans as cases is the primary mechanism by which the planner learns from its previous experiences to become more effective and efficient. The computer-aided process planner is designed to be extensible and flexible through the effective use of object-oriented principles.
Developing the Design Architecture of Life-Cycle Virtual Prototyping Systems Using Extended RCS
Authors: Lu Chris J. J. , Tsai K. H. , Yang Jackson C. S. , Wang Yu Michael 
Published: February 2021

Abstract
Virtual Prototyping has been widely applied since the breakthrough of 3-D computer graphics technology. This paper focuses on the developing methodology and design architecture of life cycle Virtual Prototyping systems. The technical rationale of this methodology, Extended Real-time Control System, is addressed first. VP systems that are established by applying this methodology will include functions of life cycle system support. Two VP systems that applied ERCS are given as examples to illustrate the powerfulness of this methodology. Finally, a comparison of this method and traditional method is provided to conclude this research.
Computations of Turbulent Flow and Heat Transfer in Staggered Tube Banks
Authors: Sharatchandra M. C. , Rhode David L. 
Published: February 2021

Abstract
Turbulent Flow in closely spaced staggered tube bundles is numerically investigated using a finite-volume approach in general curvilinear coordinates. Attention if focused on the hydrodynamic and thermal effects of the longitudinal displacement of alternate tube rows. The computations used both standard and 2-layer k–ϵ turbulence models in conjunction with a streamwise periodic finite volume formulation. The computations are in excellent agreement with experimental data for the limiting case of flow and heat transfer in undisplaced tube banks. Furthermore, the results indicate increases in both pressure drop and heat transfer with an increase in displacement. The results of this study may serve as an aid in the design of shell and tube cross flow heat exchangers.
An Inexpensive Course on Layered Manufacturing and Rapid Prototyping
Authors: Bøhn Jan Helge 
Published: February 2021

Abstract
Rapid prototyping is revolutionizing the design process. With it, less designs are being sent directly, untested, into production. Instead, designs can now be aggressively prototyped to significantly reduce the likelihood of having to correct design errors late in the product life cycle.
This paper reports on a new, experimental first-year graduate-level course that offers the students the opportunity to explore the concept of rapid prototyping and its impact on the design process. The emphasis of the course is to familiarize students with available and forthcoming automated fabrication technologies, that, when combined with secondary processing technologies, facilitate aggressive prototyping as an integral part of the design process. In particular, students are encouraged to compare and contrast the various layered manufacturing technologies and CNC machining with respect to the prototyping needs of a designer.
Fuzzy Control of an Inverted Pendulum
Authors: Balkan Tuna , Ari Mehmet Emin 
Published: February 2021

Abstract
An inverted pendulum system has been designed and constructed as a physical model of inherently unstable mechanical systems. The vertical upright position of a pendulum is controlled by changing the horizontal position of a cart to which the pendulum is hinged. The stability of the system has been investigated when a fuzzy controller is used to produce the control signal, while making a single measurement. It has been shown that by using simple fuzzy rules to allow real time computation with a single angular position measurement, the system can not be made absolutely stable. However, the stability and performance of the system have been considerably improved by shrinking the membership functions of angular position, computed angular velocity and control signal when inverted pendulum is very close to the vertical upright position.
Spreadsheet Simulation for Quick Manufacturing Analysis
Authors: Petersen Harry C. 
Published: February 2021

Abstract
Spreadsheet simulation was used to estimate peak current demands of a hypothetical welding line for LRT car bodies for energy management. Power companies factor peak power draw into their rates; high momentary power demands can result in surges and brown-outs. Rates are often based on the power used in KVA, and also on the peak current. Exceeding that peak could result in an extreme penalty. The spreadsheet simulation which developed the peak power demands generated random numbers and maped them onto resistance welder data using Monte Carlo sampling. Peak power usages were developed for the welding line during 10,000 momentary “snapshot” simulations, contracting for a 400 KVA peak, and installing a 400 KVA circuit breaker rather than pay a rate penalty. Results were developed in a few hours using a microcomputer spreadsheet program. Other potential uses of spreadsheet simulation are listed.
Finite Element Analysis of Rotational Contact-Impact Behavior of a Geared Rotor System
Authors: Tanabe Makoto , Jiang Chen Jie , Takazawa Koya 
Published: February 2021

Abstract
A simple and efficient finite element formulation and numerical method to solve it for the rotational contact-impact behavior of a geared rotor system are given. A gear element is devised to model the contact-impact behavior between gears in which the irregularity of tooth pitch is also considered. A computer program has been developed to solve this problem. Numerical examples of an electric disk grinder are demonstrated and compared with the experimental result to show the effectiveness of the present method.
The Functional Feature Model: Bridging the CAD/CAM Gap
Authors: Wearring Colin 
Published: February 2021

Abstract
Commercial CAD systems were originally developed to support the generation of 2D engineering drawings, but evolved to support development of 3D product models. Conceptually, the product model replaces 2D engineering drawings as a means for communicating product information such as size, shape, features, datums, tolerances, and other engineering specifications. Because of their history, the software architecture and data models used by commercial CAD systems do not directly represent all the engineering product information contained in 2D engineering drawings.
Computer Assisted Engineering (CAE) tools require engineering product specifications as input. When these tools are integrated directly with the CAD system, a database representation of the product model is required for their efficient operation. Without a direct link to the CAD system, information must be transferred using standard format files, or manually entered into the CAE application. To satisfy the requirements for direct integration of CAE applications with CAD systems, the Functional Feature Model (FFM) was developed. By definition, the Functional Feature Model (FFM) contains component geometry, feature definitions, datums, datum features, tolerances and other feature attributes accessed through a standard interface.
The FFM was named to distinguish the functional features used by an engineer in the definition of part function, inspection, and assembly from the features employed by CAD systems in construction of geometry. Today, the FFM is used as the basis for CAE tools which perform analysis of product Geometric Dimensioning and Tolerancing (GD&T), 3D tolerance analysis of assemblies, and CMM programming. Any CAE application which requires the same or similar information as these applications can obtain its input from the FFM.
The FFM is a mature, commercially proven prototype for a standard product model, containing the majority of engineering product information typically represented using 2D drawings annotated with Geometric Dimensional and Tolerancing (GD&T) symbols. The FFM can be used instead of 2D drawings to supply necessary product information to CAE applications. Using the FFM, there is no need to create the 2D engineering drawing, interpret the GD&T annotation, and enter the interpreted product information into the CAE application. It provides a standard interface (independent of CAD system) for commercial development of CAE applications, and is designed in a fashion which makes it appropriate for use as a basis for emerging product model standards.
The FFM provides a prototype for related activities like the Standard for the Exchange of Product Model Data (STEP) initiative represented by the Product Data Exchange using STEP (PDES) organization in the USA. Corporate and government consortiums such as the Rapid Response Manufacturing (RRM) or Simulation Assessment Validation Environment (SAVE) initiatives could employ the FFM directly to support their objectives of developing the next generation design and simulation environment.
Pressure Distributions of Drum Brakes
Authors: Huang Yuan Mao , Shyr J. S. 
Published: February 2021

Abstract
With the assumptions that the interface between the brake drum and the lining plates is perfect contact, that the friction coefficient is constant, that the thermal effect is neglected, that the brake drum and metal shoes are rigid, the pressure distributions of drum brakes are studied by using the boundary element method. The constant element is used in the two dimensional model of the drum brake for simplicity and economy. The pressure distributions on the metal shoe and the lining plate and the friction force versus the effective cam lift are compared and show good agreement with the available data. The effects of the Young’s modulus of elasticity, the angle of the arc length, the friction coefficient, the location and the thickness of the lining plate, the Young’s modulus of elasticity and the angle of the arc length of the metal shoe, and the angle of the actuating force on the pressure distributions of the drum brakes are then studied.