bluuebunny/crossref_metadata_2025_split huggingface dataset:
Patient-reported outcome measures of digitally versus conventionally constructed removable dentures: a systematic review protocol
Authors: Geerts Greta , Kimmie-Dhansay Faheema 
Published: February 2022

ABSTRACT

Objective:
This review will evaluate patient-reported outcome measures of treatment with digitally fabricated versus conventionally manufactured removable dental prostheses in partially or completely edentate adults.

Introduction:
Compared with conventionally manufactured dental prostheses, digitally fabricated prostheses may simplify and reduce the number of clinical steps and minimize errors in the production of prostheses without compromising occlusal accuracy and fit. This may, in turn, improve patient satisfaction, ability to speak, esthetics, stability, and oral health status. Determining evidence of patient-reported outcomes will assist the dental practitioner when communicating patient expectations.

Inclusion criteria:
This review will consider experimental and quasi-experimental study designs, including randomized and non-randomized controlled trials, comparative clinical studies, prospective or retrospective trials, longitudinal clinical studies, clinical reports, and technique articles. The review will include patient-reported outcome measures from fully or partially edentulous adult participants who received either conventionally or digitally fabricated dental prostheses.

Methods:
The following databases will be searched for scientific, peer-reviewed literature: Academic Search Complete, CINAHL, Dentistry and Oral Sciences (all via EBSCO), MEDLINE (PubMed), ScienceDirect, and Cochrane Central Register of Controlled Trials. The search strategy will include terms relevant to the intervention, which will be adapted for each bibliographic database, in combination with database-specific filters, where available. The language restriction will be English and Dutch. All included studies will be critically appraised and data will be extracted for synthesis. If possible, a meta-analysis will be conducted. The Grading of Recommendations, Assessment, Development and Evaluation approach will be followed to evaluate the certainty of evidence.

Systematic review registration number:
PROSPERO CRD42018094357
Oil-Film Whirl—An Investigation of Disturbances Due to Oil Films in Journal Bearings
Authors: Newkirk B. L. , Lewis J. F. 
Published: February 2022

Abstract
With three rotors and five bearings, tests have been run with oil at various viscosities to determine conditions defining a range of stable operation with cylindrical journal bearings at speeds above twice critical speed. It is concluded that short bearings, rather large clearance ratios, and moderate unit bearing loads favor a wide range of such stable operation, up to more than five times critical speed. Slight misalignment resulted in a remarkable increase of the range. After discussion of historical background and consideration of recently reported findings that seem to be at variance with those reported here, it is suggested that two substantially different phenomena should be recognized. Results of a large number of runs under which the whirl was impending (the border line of instability) are presented in two tables.
Sensitivity and Life Data on Bourdon Tubes
Authors: Mason H. L. 
Published: February 2022

Abstract
Information supplied by manufacturers to the Empirical Data Subcommittee of the ASME Research Committee on Mechanical Pressure Elements is presented in tabular and graphic form. Sensitivities are compared with the theories of Wuest, Wolf, and Clark-Gilroy-Reissner. Plots of life data as a function of maximum fiber stress are shown for steel and for phosphor bronze.
Water Tunnels for Hydraulic Investigations
Authors: Robertson J. M. 
Published: February 2022

Abstract
The water tunnel is defined as a device similar to a wind tunnel for cavitation and other hydraulic testing. A list is presented of tunnels in the United States, and the various types of tunnels are described. Cavitation, the principal phenomenon of interest in most water-tunnel researches, is discussed and its scaling factor defined. The purposes and uses for which water tunnels have been built or employed are reviewed. A bibliography on cavitation and water tunnels is included.
Design of Optimum Clearances in Positive-Displacement Pumps and Motors
Authors: Wilson W. E. 
Published: February 2022

Abstract
Since the efficiency of a positive-displacement pump or motor depends, to a great extent, upon the slip flow and the drag developed by moving surfaces, it is essential to proportion slip passages in such a manner that the energy losses are kept to a minimum. In this presentation, the slip flow and the drag on the moving elements are determined on the basis of a theory of laminar flow which takes into consideration the internal heating of the liquid and consequent reduction in viscosity. The optimum clearance, under various operating conditions is determined. It is shown that, under certain circumstances, the optimum clearance is not materially different from that predicted by the constant-viscosity theory. Under other circumstances, the minimum clearance that is physically possible is shown to be the optimum.
An Approach to the Economic Problem of Matching Condenser Surface With Exhaust-Annulus Area
Authors: Wilson W. A. , Malouf L. G. 
Published: February 2022

Abstract
The concept of economic balance as related to power-plant optimization is discussed. Its application to the problem of choosing appropriate exhaust-annulus and condensing surface areas is developed in detail. These areas are related to each other for three circulating-water temperatures and several unit-cost ratios. The exhaust conditions and the rate of change of stagnation enthalpy with investment are presented as functions of these areas.
Effect of Size on the Inlet-System Dynamics in Four-Stroke, Single-Cylinder Engines
Authors: Tsai D. H. 
Published: February 2022

Abstract
This paper describes a study of the problem of dynamic similarity in inlet systems of four-stroke, single-cylinder engines with long inlet pipes. A similarity rule formulated from a consideration of unsteady, isentropic, one-dimensional flow of a compressible fluid in the inlet pipe is checked by experiments.
Study of Pneumatic Processes in the Continuous Control of Motion With Compressed Air—II
Authors: Shearer J. L. 
Published: February 2022

Abstract
The results of analytical and experimental work reported in Part I (Paper No. 55—IRD-4) are employed in the analysis of a valve, ram, and mass-load system. This complete servomotor system is analyzed for its response to small changes of valve opening and to changes of external load force, and a simple electronic analog of the system is used to study means of providing adequate system damping. The results indicate that connecting a flow resistance and tank of suitable size to each end of the ram permits a stabilizing transient flow to each of the tanks when the ram pressures are changing rapidly. Design charts provide means of quickly finding the roots of the third-order characteristic equation for the system with transient-flow stabilization.
The Chemical Deaeration of Boiler Water—The Use of Hydrazine Compounds
Authors: Leicester J. 
Published: February 2022

Abstract
The preliminary stages in an experimental study of the reaction rates of the hydrazine-oxygen system are described. The work is continuing along four main lines, a bench-scale study of the mechanism of and the factors influencing the reaction, an investigation of reaction rates in a static autoclave system, study of reaction rates in a pilot-plant high-pressure boiler, and a series of full-scale boiler trials. The simple reaction between hydrazine and oxygen has been shown to be far more complex than was at first thought to be the case, and perhaps the most important conclusion is that even in dilute solutions this can proceed as a surface reaction. The experiments serve to indicate that in the present state of our knowledge, it would not appear possible to predict the efficiency of the reaction for a universal boiler application and that, to achieve the desired result, some form of reaction catalyst may have to be developed.
Factors Influencing the Notch-Rupture Strength of Heat-Resistant Alloys at Elevated Temperatures
Authors: Carlson R. L. , MacDonald R. J. , Simmons W. F. 
Published: February 2022

Abstract
Stress-rupture tests were conducted on notched and unnotched or plain bars of S-816, Inconel “X” Type 550, and Waspaloy alloys at test temperatures ranging from 1200 to 1600 F. The notched specimens had 50 per cent, 60-deg, V-notches with the root radii ranging from 0.005 to 0.100 in. In some tests, as many as three notches of different root radii were used. The test results indicated that S-816 alloy was notch-strengthened by all of the notches used in the temperature range from 1350 F to 1600 F. Inconel “X” Type 550 was always notch-strengthened by all of the notches only at the test temperature of 1600 F. Waspaloy was always notch-strengthened by all notches only at the temperature of 1500 F. Both Inconel “X” Type 550 and Waspaloy could be notch-strengthened for some test conditions (notch sharpness and time) at temperatures below 1600 and 1500 F, respectively. Factors considered to have an influence on stress-rupture behavior have been studied and the results are included. The factors investigated are notch geometry, notched and unnotched ductility, the modes of deformation and fracture, metallurgical changes, and surface condition. The influence of some of these factors can vary considerably from alloy to alloy. It does not appear possible, therefore, to evaluate completely the notch and unnotched stress-rupture behavior of a given alloy by any simple method. Rather, an evaluation should be based upon the combined consideration of those factors that are influential in each individual case.
Flow of Saturated Boiler Water Through Knife-Edge Orifices in Series
Authors: Monroe E. S. 
Published: February 2022

Abstract
This paper presents the results of experiments with the flow of saturated boiler water through from one to four knife-edge orifices arranged in series. A useful equation is developed to conform to both the available published data and the author’s experimental results when the back pressure on the orifice is at or near barometric condition.
Journal-Bearing Performance for Combinations of Steady, Fundamental, and Low-Amplitude Harmonic Components of Load
Authors: Shawki G. S. A. 
Published: February 2022

Abstract
This paper presents the results of an experimental study of the effect, on journal-bearing performance, of superposing the low-amplitude harmonic to fundamental and steady components of a vertical cyclic bearing load of the form P=P0+P1sin (ω1t)+Pnsin (nω1t+ψ) Amplitude ratio values (Pn/P1) of between about 0.3 and 0.4 and frequency ratio values (n) of 2, 3, and 4 are considered. Test results exhibit a bearing performance somewhat similar to that obtained with sinusoidally alternating and fluctuating loads with critical changes in performance, at (ω1/ω) (ratio of the rate of load application to that of journal rotation) slightly less than 0.5, of a character mainly dependent on the ratio (P1/P0). The striking phenomenon encountered in the tests, however, is the appearance of secondary critical changes in the performance at submultiples of the one-half speed ratio, namely, at (ω1/ω) slightly less than 0.25, 0.167, and 0.125 for second, third, and fourth superposed harmonic components of load. An explanation of this behavior is suggested. Further work on the subject is proceeding.
Studies in Lubrication—XI: Slider Bearing With Transverse Curvature; Exact Solution
Authors: Ying A. S. C. , Charnes A. , Saibel E. 
Published: February 2022

Abstract
An exact solution is developed for the Reynolds equation in the hydrodynamical theory of slider-bearing lubrication with side leakage for film thickness varying exponentially both in the direction of motion and symmetrically perpendicular to this direction. This solution is in the form of a rapidly convergent series from which calculations for the pressure distribution, total bearing load, frictional force, and so on, may be made conveniently for all length-to-width ratios, all entrance-to-exit clearance ratios, and all center-to-side clearance ratios. The results which were obtained previously by the perturbation method are shown to be quite accurate for small ratios of center-to-side clearance and, for the larger ratios, the error of the perturbation method is calculated. In fact, the present exact solution turns out to be as convenient to apply as the former approximate one and is recommended for practical consideration.
On the Theory of Discharge Coefficients for Rounded-Entrance Flowmeters and Venturis
Authors: Rivas Miguel A. , Shapiro Ascher H. 
Published: February 2022

Abstract
A theory of rounded-entrance flowmeters, based on a consideration of the potential and boundary-layer flows in a converging nozzle, is constructed. Curves are presented showing the discharge coefficient as a function of diameter Reynolds number, with the “total equivalent length-diameter ratio” of the nozzle as a parameter. The equivalent frictional length-diameter ratio of the contraction section of the ASME long-radius nozzle is presented. The theoretical curves of discharge coefficient versus diameter Reynolds number are in good agreement with experiment over a range of Reynolds number from 1 to 106. The theory provides a rational framework for correlating and extrapolating experimental results; it shows the effects of contraction shape and location of pressure taps; it furnishes values of discharge coefficient for untested designs; and it suggests precautions to be taken in design, installation, and operation.
A Method of Predicting the Effects of Notches in Uniaxial Fatigue
Authors: Dirkes W. E. 
Published: February 2022

Abstract
This paper approaches the problem of correlating notched and unnotched test data from observations of how the material may be considered to be affected under repeated stresses. A semigraphical method of extrapolating notched test data is developed. Although data available do not conclusively prove the observations reported herein, neither does presently available information refute the views presented. Individual observations are gathered together to form a picture which is intended as an aid to designers in visualizing possible trends even though complete test data are not available.
Quantitative Evaluation of Thermal-Shock Resistance
Authors: Manson S. S. , Smith R. W. 
Published: February 2022

Abstract
The dependence of thermal-shock resistance on two parameters k and σf/Eα (when k is conductivity, σf the fracture stress, E the elastic modulus, and α the coefficient of thermal expansion) is experimentally demonstrated by the fact that the relative ratings of two materials may change with a change of quench severity. The theory of thermal-shock resistance of a disk quenched at the periphery is developed, making use of the results of Jaeger. Two criteria for failure are considered; namely, the maximum normal-stress criterion, and the criterion of maximum “risk of rupture” based on the Weibull statistical theory. Equipment for subjecting these specimens to a wide range of quench severities of known surface heat-transfer coefficients is described, and results are presented for thermal-shock tests of steatite and glass disks. The results for steatite are then utilized for determination of thermal-shock parameters by four independent methods, the results showing good agreement.
A Survey of Aerodynamic Excitation Problems in Turbomachines
Authors: Sabatiuk A. , Sisto F. 
Published: February 2022

Abstract
The important blade-excitation phenomena in turbomachines are reviewed with respect to the theory extant in the literature and with respect to typical experimental results. The mechanisms of flutter, forced excitation, and rotating stall are discussed broadly and the importance of subharmonic resonance in turbine blades is introduced. Finally, general topics worthy of furthur consideration are enumerated and avenues for future research are delineated.
A New Electrical Analog Method for the Solution of Transient Heat-Conduction Problems
Authors: Liebmann G. 
Published: February 2022

Abstract
A new resistance-network analog method for the solution of heat-flow problems under transient conditions is described. In this method, electrical networks represent the difference equations which approximate the differential equations governing the problem to be solved. Temperature is represented by voltage, the spatial features of the problem by a network of parallel resistances, and the thermal constants by series resistances. A solution in steps δt of time is obtained by successive readjustments of potentiometers supplying the voltages to the network. The new method is very flexible, the time interval δt and the thermal constants being adjustable during the progress of the work. It can be applied to problems of considerable complexity. One of its outstanding features is its “stability.” Accuracies of better than 1 per cent can be obtained.
Laminar Pipe Flow With Injection and Suction Through a Porous Wall
Authors: Yuan S. W. , Finkelstein A. B. 
Published: February 2022

Abstract
The effect of injection and suction at the wall on the two-dimensional steady-state laminar flow of a fluid in a porous-wall pipe has been investigated in detail by the solution of the Navier-Stokes equations in cylindrical co-ordinates. An exact solution of the dynamic equations, reduced to a third-order nonlinear differential equation with appropriate boundary conditions, is obtained. A perturbation method was used to solve the latter equation for both small and large flows through the porous wall. The velocity components are expressed as functions of the ratio of velocity through the porous wall to the maximum axial velocity at the pipe entrance, the co-ordinates of the pipe, and the physical properties of the fluid. The results show that the effect of injection at the porous wall of the pipe is to increase the friction coefficient at the wall. For an injection ratio Q/W = 0.01 (500 ≤ Re ≤ 2500) the friction coefficient at the wall is increased by 70–85 per cent over the zero injection case (Poiseuille case).
Self-Excited Vibrations of Systems With Two Degrees of Freedom
Authors: Saljé Ernst 
Published: February 2022

Abstract
The paper reports on an investigation of vibrations of systems with two degrees of freedom. First to be considered is the dynamic behavior of a lathe spindle. Cutting conditions are of influence, and it can be demonstrated that a lathe spindle approximates vibrations in two degrees of freedom. Thereafter, a series of tests is described that were run with turning tools of relatively great overhang and with two degrees of freedom. Finally, the mathematical concept of self-excited vibrations is given. This paper may be considered as a discussion of the particular problems investigated. It does not purport to give a general theory of self-excited vibrations of the cutting processes.
The Dynamic Response of Industrial Thermometers in Wells
Authors: Linahan T. C. 
Published: February 2022

Abstract
Previously published analyses of the dynamic response of thermometers in wells have neglected either the internal distributed well resistance or the internal bulb resistance. This paper considers an “effective” resistance and capacitance of the bulb when it is in a well. The distributed resistance and capacitance of the well are included, and an approximate second-order expression for the dynamic response is developed using a combined analytical and experimental approach. There is also a brief discussion of the film coefficient of heat transfer.
Flow of a Compressible Fluid in a Thin Passage
Authors: Grinnell S. K. 
Published: February 2022

Abstract
Pressure distribution and weight-flow rate can be predicted for laminar compressible-fluid flow in a thin passage by use of the methods presented in this paper. A simplified method can be used readily when the fluid forces due to viscous action predominate over those due to acceleration of the fluid. A more complicated trial-and-error method seems to be required for larger passages where, though the flow may be laminar, the momentum effects due to acceleration of the compressible fluid are appreciable. An experimental apparatus was used to examine the validity of the analytical work. Experimental pressure distributions agree within a maximum deviation of 10 per cent with the theoretical distributions predicted by both the comprehensive and simplified theories. Experimental weight-flow rates agree within a maximum deviation of 50 per cent with predictions of the simplified theory. Dimensionless plots of pressure distribution are presented with experimental curves of flow rate versus pressure ratio for various ratios of passage length L to passage height h. These plots, together with simple equations, have been prepared for direct use by the designer.
The Effect of Oil-Column Acoustic Resonance on Hydraulic Valve “Squeal”
Authors: Ainsworth F. W. 
Published: February 2022

Abstract
An outline is presented of a theory that oil-column resonance is one likely cause of control-valve oscillation. It is shown analytically and experimentally that acoustic resonance of the oil in the lines which are attached to the valve can cause an otherwise stable valve to squeal. Methods of eliminating the oscillation are given.
Determination of Radius of Curvature for Radial and Swinging-Follower Cam Systems
Authors: Kloomok Martin , Muffley R. V. 
Published: February 2022

Abstract
An exact expression is derived for the radius of curvature of disk cams with either radial or swinging followers. Several charts are included which illustrate a quick method for arriving at a solution for a particular cam contour, such as the harmonic.
Measuring the Thermal Diffusivity of Metals at Elevated Temperatures
Authors: El-Hifni M. A. , Chao B. T. 
Published: February 2022

Abstract
The Angström-bar method has been modified and adapted to the measurement of thermal diffusivity of metals for temperatures ranging from 300 to 1050 F. A small, sinusoidal temperature fluctuation is superimposed on the mean temperature of a thin-wall tubular specimen by means of simultaneous heating and cooling at one end. Thermal diffusivity was calculated from the phase shift and amplitude ratio of the temperature waves determined at two measuring stations. The effect of possible surface heat loss is considered. Measurements were made on AISI 1018, 1045, 3140 steels, and 1.1 per cent carbon tool steel. Results obtained for electrolytic tough-pitch copper and 2S aluminum showed good agreement with a recent theory of Storm concerning the variation of thermal diffusivity of simple metals with temperature.
Demineralized Make-Up for 1250-PSI Installation at East Millinocket Mill of Great Northern Paper Company
Authors: Davidson E. F. 
Published: February 2022

Abstract
In 1952 the Great Northern Paper Company planned an increase in manufacturing capacity at its East Millinocket mill from 325 to 900 tons per day of newsprint, necessitating an enlargement of its steam-generating plant. Results of studies showed that new boilers should supply 1250 psi, 850 F steam to noncondensing extraction turbine-generators, and that the maximum amount of by-product power should be generated up to the limitation imposed by steam flow through the turbines as required for process. The problem of supplying relatively large quantities of feedwater make-up of suitable quality was a major consideration. Shortly before 1952, a number of high-capacity water-treatment installations of the demineralizing type had been installed, which provided operational background for justifying the 1250-psi steam plant from this standpoint.