bluuebunny/crossref_metadata_2025_split huggingface dataset:
The respective weights of facial signs on the perception of age and a tired‐look among differently aged Korean men
Authors: Flament Frederic , Abric Aurelie , Prunel Anne , Cassier Matthieu , Delaunay Caroline 
Published: April 2021

AbstractObjectivesTo determine the respective weights of certain facial signs on the assessment of the perceived age and a tired‐look on Korean men of different ages.Material and MethodsPhotographs were taken of the faces of 101 Korean men (20‐80 years) under standardized conditions. These photographs allowed to define 16 signs, which were then graded by 15 experts/dermatologists, using standardized scales provided by a referential Skin Aging Atlas. These signs were dispatched into 5 clusters, namely Wrinkles/Texture, Ptosis/Sagging, Cheek pores, Pigmentation, and Vascular signs. A naïve panel of 200 Korean individuals (100 women, 100 men), of similar age range, were asked, when viewing full‐face photographs, to (a) attribute on a 0‐10 scale their perception of a tired‐look and (b) estimate the age of the subject.ResultsThe severity of all clusters increased with age, although at different rates. The Wrinkles/Texture or Ptosis/Sagging showed a rather regular progression, whereas Vascular presented the weakest changes. Although perceived and real ages were found highly correlated, almost 85% of the subjects were judged older by 1‐15 years. The signs/clusters were found significantly correlated with perceived age, highly for Wrinkles/Texture and Ptosis/Sagging, moderate for Pigmentation, and low for Vascular and Cheek pores. The weights in perceived ages of Wrinkles/Texture and Ptosis/Sagging represent 81% and Pigmentation at 19%. Facial tired‐look of Korean men was found significantly correlated with perceived age. Although Vascular and Cheek pores were found not impacting, Wrinkles/Texture, Ptosis/Sagging, and Pigmentation presented a clear influence.ConclusionWithin facial clusters, Wrinkles/Texture, Ptosis/Sagging, and Pigmentation are major factors in the assessment of perceived age in Korean men. The perception of an increased tired‐look is significantly associated with increased perceived age.
Avoiding Gaps in Romance: Evidence from Italian and French for a Structural Parsing Principle
Authors: Konrad Ingrid , Burattin Massimo , Cecchetto Carlo , Foppolo Francesca , Staub Adrian , Donati Caterina 
Published: April 2021

AbstractExisting evidence suggests that the parser avoids positing a movement dependency if the grammar does not require doing so. By investigating the processing of two syntactic ambiguities that have not been the subject of processing studies before, we provide more conclusive evidence for this parsing bias in two Romance languages: French and Italian. In two acceptability‐judgment experiments and two self‐paced‐reading studies, we found that sentences that involved a filler–gap dependency (indirect questions in Italian and free relatives in French) were dispreferred compared to sentences involving the same lexical material but no filler–gap dependency (declarative complement clauses in both languages). Crucially, the filler–gap dependency was not dispreferred when there was no available competitor. We conclude by discussing the relevance of these results for syntactic theory, in particular for the questionable status of Merge over Move as a grammatical principle.
Methodological Considerations for Incorporating Clinical Data Into a Network Model of Retrieval Failures
Authors: Castro Nichol 
Published: April 2021

AbstractDifficulty retrieving information (e.g., words) from memory is prevalent in neurogenic communication disorders (e.g., aphasia and dementia). Theoretical modeling of retrieval failures often relies on clinical data, despite methodological limitations (e.g., locus of retrieval failure, heterogeneity of individuals, and progression of disorder/disease). Techniques from network science are naturally capable of handling these limitations. This paper reviews recent work using a multiplex lexical network to account for word retrieval failures and highlights how network science can address the limitations of clinical data. Critically, any model we employ could impact clinical practice and patient lives, harkening the need for theoretically well‐informed network models.
On the Impact Behavior of a Material With a Yield Point
Authors: White Merit P. 
Published: April 2021

Abstract
An analysis of longitudinal impact tests that were made by Drs. D. S. Clark and P. E. Duwez at the California Institute of Technology on an iron and a steel with definite yield points is described. From this analysis is deduced the probable nature of the dynamic stress-strain relations for such materials. These appear to differ greatly from the static stress-strain relations, unlike the case for materials without yield points. As pointed out by Duwez and Clark, the upper yield stress for undeformed material is several times as great under impact as the static yield stress. The present analysis indicates that under impact, the material with a definite yield point is made harder at a given deformation, and ruptures at a higher (engineering) stress and smaller strain than when loaded statically. The critical impact velocity, defined as that at which nearly instantaneous failure occurs in tension, is discussed, and the factors upon which it depends are given.
Thermal Stresses in a Rectangular Plate Clamped Along an Edge
Authors: Aleck B. J. 
Published: April 2021

Abstract
An approximate solution has been obtained for the stresses induced by a uniform change in temperature of a thin rectangular plate, clamped along an edge. The solution has been carried to completion for plates whose clamped edge is long, i.e., more than 5 times the length of the perpendicular free edge. The solution for smaller ratios of clamped to perpendicular lengths is expressed in terms of six determined functions whose coefficients are to be evaluated by satisfying two boundary conditions. The thermal-stress problem is first converted to one of specified boundary tractions. The normal stress, σx, parallel to the clamped edge is assumed of the form σx = f1 (x) + y f2(x) + y2f3(x), where fi(x) are as yet undetermined functions, and where y is the co-ordinate at right angles to the clamped edge. Using the equations of equilibrium and the boundary conditions, τxy and σy are expressed in terms of powers of y and the derivatives of fi(x). The integral representing the strain energy is then expressed in terms of the expressions for σx, σy, and τxy. In accordance with the principle of least work, the integral representing the strain energy is minimized, using the calculus of variations. The resulting simultaneous differential equations for fi(x) are solved as a linear combination of twelve functions (six of which drop out, by symmetry). Given f1(x), then f2(x) and f3(x) are determinate by virtue of the simultaneous equations. The six coefficients in the expression for f1 are evaluated by satisfying the boundary conditions along the free edges. The maximum normal stress concentration, over 10, occurs at the junction of the free and clamped edges.
Slow-Motion Pictures of Impact Tests by Means of Photoelasticity
Authors: Foeppl Ludwig 
Published: April 2021

Abstract
The experiments described in this paper were carried out in investigating the distribution of stresses and their variation with time in a test bar subject to bending stresses resulting from an impact. While a series of tests has been made, only two of them will be dealt with in detail. In the first test the impact is of moderate intensity, so that the response is entirely elastic. The test results will be compared with a theoretical treatise by St. Venant and Flamant published in 1889. In the second test the impact is strong enough to break the test bar.
Supersonic Diffusers for Wind Tunnels
Authors: Neumann E. P. , Lustwerk F. 
Published: April 2021

Abstract
An investigation of supersonic diffusers was conducted for conditions wherein a boundary layer was present at the diffuser entrance. The pressure rise obtained from a shock in a constant-area tube was measured, and the measurements compared with values computed from a simple one-dimensional analysis. For the range of Mach numbers covered (1.8 to 4.2), separation of the stream from the tube wall was always induced by the shock. The length of the separated region was from 8 to 12 tube diameters. The results of the tests on shocks in a constant-area tube were utilized in the design of several types of diffusers for which test data are reported at Mach numbers ranging from 2 to 3. The most efficient diffuser tested consisted of a contraction to a minimum starting area followed by a constant-area tube approximately 10 diam long. The tube was in turn followed by a subsonic diffuser. Only diffusers of constant geometry were considered.
Note on the Bending of Circular Plates of Variable Thickness
Authors: Conway H. D. 
Published: April 2021

Abstract
In a recent paper a solution was given to the problem of a symmetrically loaded circular plate with a central hole, the thickness of the plate at any section being proportional to the distance of the section from the center of the plate. A very simple solution can be obtained for another variation of thickness of which the foregoing is a special case.
The Dynamics of Cavitation Bubbles
Authors: Plesset M. S. 
Published: April 2021

Abstract
Three regimes of liquid flow over a body are defined, namely: (a) noncavitating flow; (b) cavitating flow with a relatively small number of cavitation bubbles in the field of flow; and (c) cavitating flow with a single large cavity about the body. The assumption is made that, for the second regime of flow, the pressure coefficient in the flow field is no different from that in the noncavitating flow. On this basis, the equation of motion for the growth and collapse of a cavitation bubble containing vapor is derived and applied to experimental observations on such bubbles. The limitations of this equation of motion are pointed out, and include the effect of the finite rate of evaporation and condensation, and compressibility of vapor and liquid. A brief discussion of the role of “nuclei” in the liquid in the rate of formation of cavitation bubbles is also given.
General Features of Plastic-Elastic Problems as Exemplified by Some Particular Solutions
Authors: Hill Rodney 
Published: April 2021

Abstract
New complete solutions based upon the Reuss equations are obtained for various plastic-elastic problems. These include the expansion of a spherical shell and of a cylindrical hole in an infinite medium. The solutions are used to exemplify certain features common to all plastic-elastic problems, with a view to introducing valid approximations in more complex cases.
A Matrix Method of Calculating Propeller-Blade Moments and Deflections
Authors: Plunkett R. 
Published: April 2021

Abstract
A new method is demonstrated for finding the bending moments and deflections of a twisted cantilever beam due to both transverse and axial loads. The actual physical system is approximated by a lumped or discrete system which is handled by matrix methods. It is shown that good accuracy may be expected even with slide-rule computation, since the method corresponds to a set of successive numerical integrations. The setup is particularly adapted to investigating the effects of changing the initial offset and of different rotating speeds of a propeller or turbine blade. In addition, a procedure is demonstrated for the application of a successive approximation method, analogous to a Stodola solution, to a problem which would otherwise show oscillating divergent results.
The Effect of an Axial Force on the Vibration of Hinged Bars
Authors: Woinowsky-Krieger S. 
Published: April 2021

Abstract
It can be shown that the vibration of an extensible bar, carrying no transverse load and having the ends fixed at the supports, causes an axial tensile force with a period equal to the half-period of the vibration of the bar. This force modifies the process of the vibration to a nonlinear one and produces an increase of the frequency of vibration according to the increase of the amplitude.
Graphical, Mechanical, and Electrical Aids for Compressible Fluid Flow
Authors: Poritsky H. , Sells B. E. , Danforth C. E. 
Published: April 2021

Abstract
Graphical, mechanical, and electrical methods of studying two-dimensional and axially symmetrical irrotational flow of nonviscous compressible fluids are described and examples are given of problems solved by these methods. Rules for the construction of compressible flux plots using wires, beads, and a suitable device for obtaining the desired length-width ratios of the rectangles are derived, and the apparatus used is described. An analogy is described by means of which these problems can be solved by the use of a d-c resistance board, employing variable resistances which are adjusted to conform to the derived relations. Designers and aerodynamicists in need of solution for problems for which no analytical solutions are available can use the methods described in this paper to obtain the required solutions.
Deflections and Moments Due to a Concentrated Load on a Cantilever Plate of Infinite Length
Authors: Jaramillo T. J. 
Published: April 2021

Abstract
This paper contains an exact solution in terms of improper integrals for the deflections and moments due to a transverse concentrated load acting at an arbitrary point of an infinitely long cantilever plate of constant width and thickness. The solution is transformed into series form by means of contour integration, and is illustrated by numerical examples. In particular, comparisons are made with the known solution (1) for the special case where the load is applied at the free edge of the plate. The results obtained are of practical significance in connection with the design of certain types of monorail cranes.
Acceleration of the Instant Center
Authors: Carter W. J. 
Published: April 2021

Abstract
The acceleration of the members of a mechanism having a “floating link,” such as that in Fig. 2, are not obtainable by the method of relative accelerations. Beskin has given a solution for this problem which involves the determination of the center of trajectory of points on a connecting link. The method presented in this paper makes use of the acceleration of the instant center of velocity, the acceleration of which is dependent only on the velocity of the linkage elements. The method developed may also be used to obtain the accelerations for linkages which normally require the use of Coriolis’ law.
Atomization of Liquids by Means of a Rotating Cup
Authors: Hinze J. O. , Milborn H. 
Published: April 2021

Abstract
Liquid, supplied through a stationary tube to the inner part of a rotating cup widening toward a brim, flows viscously in a thin layer toward this brim and is then flung off, all by centrifugal action. The flow within this layer and the disintegration phenomena occurring beyond the brim have been studied, experimentally as well as theoretically. A formula has been derived for the thickness and for the radial velocity of the liquid layer within the cup, which proved to agree reasonably well with experimental results. Three essentially different types of disintegration may take place around and beyond the edge of the cup designated, respectively, by: (a) the state of direct drop formation; (b) the state of ligament formation; and (c) the state of film formation. Which one of these is realized depends upon working conditions. Transition from state (a) into (b), or of state (b) into state (c) is promoted by an increased quantity of supply, an increased angular speed, a decreased diameter of the cup, an increased density, an increased viscosity, and a decreased surface tension of the liquid. The experimental results have been expressed in relationships between relevant dimensionless groups. For the state of ligament formation a semiempirical relationship has been derived between the number of ligaments and dimensionless groups determining the working conditions of the cup. Results of drop-size measurements made for the state of ligament formation as well as for the state of film formation show that atomization by mere rotation of the cup is much more uniform than commonly achieved with pressure atomizers.
Gaskets and Bolted Joints
Authors: Roberts Irving 
Published: April 2021

Abstract
This paper consists of a study of the loading requirements of gaskets in bolted joints, with the object of developing a rational basis for design of such joints. Starting with an analysis of gasket conditions for tightness, the gasket factor m is defined, and its variation with initial gasket stress and gasket width is predicted. These trends are confirmed by a survey of the available literature data.
In a bolted joint, gasket stress becomes a function of the elastic constants of the system. Equations are derived to predict gasket and bolt stresses resulting from application of internal fluid pressure, and typical elastic recovery curves for an asbestos gasket are presented. Consideration is given to the effect of gasket creep in a bolted joint, and to the problem of distribution of bolt load, for which an approximate theory is derived.
On this basis, defects in the ASME Code are pointed out, and a tentative new design procedure is proposed. Finally, a summary of data which should be obtained for use with the new design procedure is given.
Longitudinal and Torsional Impact in a Uniform Bar With a Rigid Body at One End
Authors: Burr A. H. 
Published: April 2021

Abstract
A uniform bar carrying a rigid body at one end is analyzed for those cases where its other end is struck by a rigid body, and struck by a bar and body, also for the case of sudden application of force at either end. Recurrence formulas are derived in nondimensional form and applied to determine in a finite number of terms the stress equations for striking impact and for a constant-force impact. Some useful theorems and simplifications, applicable to other problems of this nature, are indicated. For striking impact by a rigid body, charts show the time-variation of stress and the maximum stress for a range of physical values of the bar and bodies. Application to the design of bars, helical springs, and shafts is discussed.
The Calendering of Plastic Materials
Authors: Gaskell R. E. 
Published: April 2021

Abstract
Many industries, notably the paper, linoleum, rubber, and steel industries, use a rolling process to form or otherwise treat sheets of these various materials. To most engineers, perhaps, the term “rolling” brings to mind only the rolling of steel or aluminum—solids with definite yield points. Several mathematical studies of the rolling of such materials have already been made. In those studies, any shear stress beyond the yield stress is neglected. The plastic materials handled by other industries, however, do not often have the definite yield point of steel, or, after yielding takes place, they may behave more like liquids of very high and usually variable viscosity. Shear stress beyond the yield point, due to viscosity, cannot therefore be neglected. Consequently, a different approach must be made if a mathematical description of the process is to be formulated. Such an approach is made in this paper.
Matrix Solution for the Vibration of Nonuniform Beams
Authors: Thomson W. T. 
Published: April 2021

Abstract
A matrix method for the determination of natural frequencies of any nonuniform beam is presented. It accomplishes the same task as that of Myklestad’s tabular method with the added advantage of simplicity of formulation. Included is a procedure for the case where the nonuniform beam is represented by a series of uniform sections.
The Theory of Spring-Loaded Valves for Reciprocating Compressors
Authors: Costagliola Michael 
Published: April 2021

Abstract
The inlet and discharge processes of a reciprocating compressor equipped with spring-loaded valves of the automatic type have been analyzed to determine the effects of the main design variables on performance. The most important criterion is found to be a parameter involving effective flow area through the valves and piston speed. Valve dynamics is a secondary consideration. For optimum valve dynamics, the valve would have no weight and a very small spring constant, giving an infinite natural frequency of the valve system. If certain valve characteristics are known (or measured by static-flow test), the performance of a compressor using these valves can be predicted with fair accuracy.
A MEMS-Based Drug Delivery Device With Integrated Microneedle Array—Design and Simulation
Authors: Meshkinfam Farshid , Rizvi Ghus 
Published: April 2021

Abstract
One of the most effective treatments for type 1 and 2 diabetes is the administration of Insulin. Single needle mechanical insulin pumps are heavy and painful. Microneedle-based MEMS drug delivery devices can be an excellent solution for insulin dosing. The stackable structure provides minimum dimensions and the final product can be in the form of a patch that can be applied to any flat area of human skin. The use of microneedle array provides a safe, painless, and robust injection application. The design of positive volumetric insulin pump is a Multiphysics problem where the volumetric changes of the main pump chamber and the pumped fluid are directly coupled. We use a Multiphysics simulation system to investigate the performance of a MEMS-based insulin micropump with a piezoelectric actuator pumping a viscous Newtonian fluid. The model captures the accumulated out-flow, the netflow, or flow fluctuations based on deflection of piezoelectric diaphragm actuator. Different input voltages and different excitation frequencies cause movement of piezoelectric actuator, which moves the diaphragm disk in positive–negative directions thereby inducing discharge pressures at the microneedle array. In this study, we address various aspects of design and simulation of a MEMS-based piezoelectric insulin micropump including polydimethylsiloxane microvalves and microneedle array. We investigate the micropump performance at human skin interfacial pressure to match minimum to maximum delivery targets/requirements for total range of diabetic patient's expected operating parameters. comsolmultiphysics is used for this study.
Design of a Compact Magnetically Levitated Blower for Space Applications
Authors: Hawkins Larry , Filatov Alexei , Khatri Rasish , DellaCorte Chris , Howard S. Adam 
Published: April 2021

Abstract
NASA is leading the design and development of a next-generation CO2 removal system, the four bed carbon dioxide scrubber (4BCO2), and intends to use the International Space Station (ISS) as its testbed. A key component of the system is the blower that provides the airflow through the CO2 sorbent beds. To improve performance and reliability, magnetic levitation (magnetic bearings) will be used in lieu of more conventional bearings (e.g., ball bearings or air bearings) to improve resistance to contaminants and enable extensibility with regards to blower speed, pressure rise and mass flow rate. The blower will pull air from the ISS through an adsorbing desiccant bed and push it through a CO2 sorbent bed and desorbing desiccant bed. The 4BCO2 blower features an overhung permanent magnet motor, a centrally located five-axis, active magnetic bearing system, backup bearings, and an overhung centrifugal impeller in a very compact package. Magnetic bearings are a natural choice for this application due to low power consumption, low transmitted vibration and oil free operation. This article describes the design considerations and design selections for the blower system with a focus on the magnetic bearings. Magnetic FEA of the actuator/sensor system, rotordynamics/controls analysis, and backup bearing drop simulations are discussed in detail. It is expected that the successful implementation of magnetic bearings for this space application will encourage the more widespread adoption in other space applications (e.g., fluid pumps, reaction wheels) that challenge conventional bearing technologies.