bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Theory for the Buckling of Thin Cylinders Under Axial Compression and Bending
Authors: Donnell L. H. 
Published: February 2023

Abstract
The results of experiments on axial loading of cylindrical shells (thin enough to buckle below the elastic limit and too short to buckle as Euler columns) are not in good agreement with previous theories, which have been based on the assumptions of perfect initial sbape and infinitesimal deflections. Experimental failure stresses range from 0.6 to 0.15 of the theoretical. The discrepancy is apparently considerably greater for brass and mild-steel specimens than for duralumin and increases with the radius-thickness ratio. There is an equally great discrepancy between observed and predicted shapes of buckling deflections.
In this paper an approximate large-deflection theory is developed, which permits initial eccentricities or deviations from cylindrical shape to be considered. True instability is, of course, impossible under such conditions; the stress distribution is no longer uniform, and it is assumed that final failure takes place when the maximum stress reaches the yield point. The effect of initial eccentricities and of large deflections is much greater than for the case of simple struts. Measurements of initial eccentricities in actual cylinders have not been made; however, it is shown that most of these discrepancies can be explained if the initial deviations from cylindrical form are assumed to be resolved into a double harmonic series, and if certain reasonable assumptions are made as to the magnitudes of these components of the deviations. With these assumptions the failing stress is found to be a function of the yield point as well as of the modulus of elasticity and the radius-thickness ratio. On the basis of this a tentative design formula [5] is proposed, which involves relations suggested by the theory but is based on experimental data.
It is shown that similar discrepancies between experiments and previous theories on the buckling of thin cylinders in pure bending can be reasonably explained on the same basis, and that the maximum bending stress can be taken as about 1.4 times the values given by Equation [5]. It is also shown that puzzling features in many other buckling problems can probably be explained by similar considerations, and it is hoped that this discussion may help to open a new field in the study of buckling problems. The large-deflection theory developed in the paper should be useful in exploring this field, and may be used in other applications as well.
The paper presents the results of about a hundred new tests of thin cylinders in axial compression and bending, which, together with numerous tests by Lundquist form the experimental evidence for the conclusions arrived at.
The Leakage of Steam Through Labyrinth Seals
Authors: Egli Adolf 
Published: February 2023

Abstract
This paper gives a rational theoretical treatment of the labyrinth problem, based on the actual flow characteristics typical for a sharp-edged orifice. The general relations between leakage, number of throttlings, and pressure distribution are given in graphical form on a chart intended for use in practical turbine design.
It is also shown how the effect of kinetic energy being carried from one throttling into the next can be considered rationally. The numerical constants left open by the theory are derived experimentally with the aid of a static labyrinth leakage-testing device.
The Uniform-Section Disk Spring
Authors: Almen J. O. , Laszlo A. 
Published: February 2023

Abstract
The authors point out in this paper that initially coned annular-disk springs of uniform cross section may be proportioned to give a wide variety of load-deflection curves not readily obtainable with the more conventional forms of springs, and that, although the versatility of this type spring has long been indicated, the formulas available have not been presented in a manner to disclose readily the effect of spring proportions on characteristics. Therefore the authors have derived the formulas presented in this paper with the intention that the formulas will aid the designer in arriving at suitable characteristics by choice of spring geometry. These new formulas have been in use for several years at the General Motors Corporation research laboratories section, and their reliability has been checked by tests of springs used in a variety of special test equipment.
The Effect of Installation on the Coefficients of Venturi Meters
Authors: Pardoe W. S. 
Published: February 2023

Abstract
The author presents the results of a series of tests conducted to determine the effect of the location of a venturi meter on its coefficient of discharge. These results are shown graphically together with sketches of the type of installations and venturi meters for which the coefficients were determined. The author shows mathematically and experimentally that for normal turbulence and shooting flow the coefficients are the same for low-ratio meters, but that for high-ratio meters the coefficient increases from that for shooting flow to the normal value in about 20 diameters of mixing lengths.
A Review of Existing Psychrometric Data in Relation to Practical Engineering Problems
Authors: Carrier W. H. , Mackey C. O. 
Published: February 2023

Abstract
The authors review and correlate available psychrometric data, and discuss the application of these data to engineering problems. They analyze and correlate existing data with reference to deviations of observed wet-bulb temperatures from those of true adiabatic saturation. The paper also includes a tabulation of revised psychrometric values in accordance with the latest physical data with correction factors for all normal variations of barometric pressures. The authors make an analysis and give a demonstration of the proper method of employing the psychrometric heat function previously defined as the “total heat less the heat of the liquid”, and afterward referred to in psychrometry as “total heat”. For this function the authors offer the term “sigma function”, to distinguish it from the enthalpy or true total heat which includes the heat of the liquid.
The Condensation of Flowing Steam Part I—Condensation in Diverging Nozzles
Authors: Yellott J. I. , Holland C. K. 
Published: February 2023

Abstract
The authors discuss the apparatus and method used in determining the point of condensation in diverging nozzles. The discussion is restricted to nozzles with very short throats and with angles of divergence greater than 2 deg. As a primary result of the work described, the authors locate the Wilson line for continuously expanding steam at the 4.5 per cent moisture line on the Mollier diagram. Condensation points and sizes of steam droplets are discussed for various pressure and temperature conditions before expansion and for various back pressures.
Determination of the Relative Resistance to Cavitation Erosion by the Vibratory Method
Authors: Kerr S. Logan 
Published: February 2023

Abstract
The cavitation-erosion tests described in this report were made under the direction of the mechanical section, U. S. Engineer Office, Eastport, Me., at the Massachusetts Institute of Technology, Cambridge, Mass., by Prof. H. Peters. The investigation was part of the materials-corrosion investigation, made to provide an accurate basis for the selection of the proper materials to be used in the construction of the large hydroelectric units required on the Passamaquoddy project. No information was available upon the cavitation resistance of materials in sea water as compared with their behavior in fresh water. The program included tests on 80 materials in a newly developed vibratory apparatus and the behavior of three materials in the venturitype apparatus used for previous investigations. Reliable results were obtained on the behavior of materials in sea water as compared with fresh water, and the relation between cavitation damage and temperature was established.
Timber-Connector Construction
Authors: Hayward Phillips A. 
Published: February 2023

Abstract
The use of timber-connector construction has been acknowledged by authorities as one of the outstanding developments in modern-day use in wood construction. Up to the present time, over nine thousand structures, utilizing some three million board feet of lumber, have been built in which this improved system of timber construction was employed. Structures range all the way from small portable Civilian Conservation Corps camp buildings and low-cost homes, to all-wood radio towers, 326 ft high, and 700-ft timber highway bridges. Wood has repeatedly increased its standing as an engineering material through the use of timber connectors.
This paper tells of the introduction of timber connectors into the United States and gives an analysis of the various types and their possibilities in construction. Particular reference is made to the fact that through their use the strength of wood is increased approximately four times. Important projects in which timber connectors are used are discussed.
Effects of Speed and Pressure on Cutting Rate of Coated Abrasive Products
Authors: Hager E. T. 
Published: February 2023

Abstract
The cutting rate of coated abrasive products, when used for sanding wood, is quite sensitive to changes in belt speed and work pressure. The results of such changes, specific to the conditions of these tests only, are presented in this paper. In addition, some general trends and limitations are indicated which it is believed are applicable outside of the specified conditions.
The tests were made with 1/0–80 and 3/0–120 grit electro-coat (Aloxite) belts taken from regular stock material. A Porter-Cable Belt Sander, belt size 6 × 54½ in., was used, the only change made in the machine being the substitution of a 5-hp variable-speed d-c motor. Most of the work was done on hard maple. A few tests were made on yellow birch.
Combustion of Pulverized Coal
Authors: Kreisinger Henry 
Published: February 2023

Abstract
This paper deals with the combustion of pulverized coal with special reference to water-cooled furnaces. It discusses the effect of various factors on ignition, and follows the process of combustion through the furnace. The factors that are given consideration are the amount of primary air, admission of secondary air, fineness of coal, percentage of moisture and volatile matter in coal, characteristics of ash, mixing, oxygen concentration, and furnace temperature.
The Elastic Theory of Wood Failure
Authors: Norris Charles B. 
Published: February 2023

Abstract
This paper deals with various theories advanced for the failure of wood. The formulas developed by Jacoby, Howe, and Hankinson for expressing the crushing strength of wood are examined and their relative practical value indicated. Of the three the Hankinson formula, while being strictly empirical, agrees with experimental results better than the others. The author then proceeds to outline the steps of derivation of Hankinson’s formula, applying the theory of failure advanced by Hencky. A second theory is analyzed which also leads to Hankinson’s formula. The author points out that the methods used in deriving Hankinson’s formula are very approximate but that such a formula is better than none.
Design Factors Controlling the Dynamic Performance of Instruments
Authors: Draper C. S. , Bentley G. P. 
Published: February 2023

Abstract
This paper presents a generalized treatment of instruments which have a single movable index, controlled by the magnitude of a single actuating quantity. Such an instrument acts as a system with one degree of freedom and is studied by the well-known methods developed for such systems. Instruments which include servomechanisms cannot be treated as systems with one degree of freedom and are therefore excluded from consideration. From the standpoint of static indications, it is shown that the essential properties of an instrument can be specified in terms of range, scale sensitivity, calibration error, environmental error, and uncertainty. The definition and use of each of these quantities is discussed.
It is shown that the response of an instrument to rapid changes in the actuating quantity can be calculated if two parameters called instrument characteristics are known. One of these parameters has the dimension of time and is called the characteristic time. The second parameter is nondimensional and is called the damping ratio. Nondimensional curves, showing instrument responses to three typical variations in the actuating quantity, are plotted for a series of values of the damping ratio. These curves are used in an illustrative example to show how the values of the instrument characteristics, required to keep dynamic errors below a given limit, can be determined in a practical case.
Investigations of the Bump Foil Bearing With Thick Top Foil Based on Contact Mechanics
Authors: Li Jie , Li Changlin , Du Jianjun 
Published: February 2023

AbstractTraditional bump foil bearing, though widely used, is considered to have the problem of inadequate load capacity due to the effect of foil sag between adjacent bumps. In this paper, the thick top foil is applied to cope with the heavy load conditions, which has one order of magnitude larger top foil thickness than traditional top foil. Thick plate and curve shell models are developed to calculate the load-carrying performance of thick top foil bearing based on contact mechanics, and the sag ratio is introduced to describe the degree of foil sag and estimate the bearing load capacity. The impacts of top foil thickness on the stiffness of bearings in different sizes as well as on the adaptability to rotor tilt are discussed. The results indicate that the thick top foil (tt = 2 mm) bearing performs a nearly 100% enhanced load capacity at small gas film thickness whether rotor tilts or not. Thick top foil will increase the bearing stiffness of small size (d = 35 mm) and tends to have little influence on large-size bearing stiffness (d = 70 mm).
The Relationship of Coach-Created Motivational Climate to Teamwork Behaviors in Female Collegiate Athletes
Authors: Sokoloff Derek M. , Petrie Trent A. , Chu Tsz Lun (Alan) 
Published: February 2023

Although teamwork behaviors would be expected to emerge from coach-created task-involving climates, no study has focused on this connection. Thus, we surveyed female National Collegiate Athletic Association (NCAA) Division I athletes (N = 536) on their perceptions of motivational climates created by their head coaches (i.e., 33-item Perceived Motivational Climate in Sport Questionnaire) and their beliefs about their team’s teamwork behaviors (i.e., 19-item Multidimensional Assessment of Teamwork in Sport—Short Form). Cluster analyses revealed three groupings of coach-created climates: low task/high ego (n = 125), moderate task/moderate ego (n = 286), and high task/low ego (n = 125). Through a series of multivariate analyses of variance, with post hoc discriminant descriptive analysis, we found a significant main effect for the motivational climate clusters on teamwork behaviors. Athletes in the high-task/low-ego motivational climate cluster endorsed more teamwork behaviors (e.g., preparation, execution) than those in the moderate-task/moderate-ego and low-task/high-ego climate clusters. These findings suggest the importance of coach-created motivational climates in teamwork behaviors.
Crustal conductivity footprint of the orogenic gold district in the Red Lake greenstone belt, western Superior craton, Canada
Authors: Adetunji Ademola Q. , Launay Gaetan , Ferguson Ian J. , Simmons Jack M. , Ma Chong , Ayer John , Lafrance Bruno 
Published: February 2023

AbstractA magnetotelluric (MT) study across the Red Lake greenstone belt of the western Superior craton, Canada, images a 50-km-long north-dipping conductor (&lt;20 Ω·m) at 20–25 km depth and subvertical conductors spatially correlated with crustal-scale shear zones and large orogenic gold deposits. The conductors are interpreted to be the conductivity signature of the deep crustal source of the auriferous fluids and pathways of the orogenic gold system. The geophysical results, supported by existing geochemical and fluid inclusion studies, suggest that the Au- and CO2-rich fluids responsible for gold mineralization were released by devolatilization of supracrustal rocks underthrust to mid- to lower-crustal levels during subduction. This MT study links shallow gold mineralization to a deep crustal source region, demonstrating the connection between a crustal suture zone and the formation of orogenic gold deposits in an Archean greenstone belt.
Multiple spatial and temporal scales of deformation from geodetic monitoring point to active transcrustal magma system at Uturuncu volcano, Bolivia
Authors: Eiden Elizabeth , MacQueen Patricia , Henderson Scott , Pritchard Matthew 
Published: February 2023

AbstractUturuncu volcano in southern Bolivia last erupted around 250 ka but is exhibiting signs of recent activity, including over 50 yr of surface uplift, elevated seismic activity, and fumarolic activity. We studied the spatial and temporal scales of surface deformation from 1992 to 2021 to better understand subsurface activity. We tracked Uturuncu’s recent deformation using interferometric synthetic aperture radar (InSAR) data and the global navigation satellite system (GNSS) station UTUR, located near Uturuncu’s summit. We observed a spatially coherent signal of uplift from 2014 to 2021 from Sentinel-1 A/B satellites that indicates the Altiplano-Puna magma body, located 19–24 km below ground level, and previously noted as the source of the large region of deformation, is still active. The ground is now uplifting at a rate of ~3 mm/yr compared to prior rates of ~10 mm/yr. We corroborated this waning uplift with in situ data from station UTUR. We combined the Sentinel-1 data with TerraSAR-X interferograms to constrain an ~25 km2 region of subsidence located 11 km SSW of Uturuncu, with a source depth of 2.1 km below ground level to an active period of ~2.5 yr with ~5 mm/yr subsidence. We developed a conceptual model that relates these varying depths and time scales of activity in a transcrustal magmatic system. We associate the surface uplift with pressurization from ascending gases and brines from magmatic reservoirs in the midcrust. We infer the existence of brine lenses in the shallow hydrothermal system based on low subsurface resistivity correlated with surface subsidence.
Content analysis of Dutch newspaper coverage of three tobacco control policies, 2017–2019
Authors: Poole Nikita L , van Straaten Barbara , van den Brand Floor A , Gilmore Anna B , Willemsen Marc C , Nagelhout Gera E 
Published: February 2023

ObjectivesNews media coverage can influence support for and implementation of tobacco control policies. This research aims to analyse and compare newspaper coverage of newly implemented policies: a substantial tobacco tax increase, point-of-sale display ban and plain packaging.DesignWe conducted a content analysis of articles covering the three policies from ten national Dutch newspapers. Articles published between November 2017 and November 2019 were coded for type and tone. The policy dystopia model was used to code arguments opposing the policies. Tobacco industry appearances in news articles were also analysed for frequency and type.ResultsA total of 134 news articles were analysed, of which the industry appeared in 28%. The majority of coverage was neutral in tone, although among articles that were coded as expressing a positive or negative tone, plain packaging and the point-of-sale ban were portrayed more negatively than positively. Negative coverage was predominantly accounted for by industry presence. Arguments opposing the policies focused on negative economic consequences, challenging the need for policy and adverse consequences for retailers for tax, plain packaging and the point-of-sale display ban, respectively. We identified six specific new arguments that fit within existing domains of the policy dystopia model.ConclusionsThe tobacco industry and its allies still appear in a substantial proportion of news articles in relation to tobacco policy. This study identifies contemporary industry arguments against tobacco control policies in Europe which, alongside the policy dystopia model, can be used to predict and counter the tobacco industry’s future attempts to oppose policies.
Barriers to family planning use in the Eastern Democratic Republic of the Congo: an application of the theory of planned behaviour using a longitudinal survey
Authors: Bapolisi Wyvine Ansima , Bisimwa Ghislain , Merten Sonja 
Published: February 2023

ObjectiveIn the Democratic Republic of the Congo, there is a low adherence of the population to the use of family planning (FP) due to various social barriers. This study aimed to understand the drives from social barriers to the use of FP in women in the Kivu, a region particularly affected by poverty and many years of conflicts. A theory of planned behaviour (TPB) using a generalised structural equation modelling has been applied to understand the complex sociocultural drivers to the intention and the ultimate decision to use FP.DesignLongitudinal study.SettingA community-based approach was used to investigate FP use in the North and South-Kivu regions.ParticipantsOverall, 1812 women 15 years and older were enrolled in the baseline study and 1055 were retrieved during the follow-up.Primary and secondary outcomesFP use and intention to use FP.ResultsThe mean age was 36±12.9 years, with a minimum of 15 years old and a maximum of 94 years old. Among sexually active participants, more than 40% used a modern contraceptive method at the last sexual intercourse. Education was positively and significantly associated with intention to use FP (β=0.367; p=0.008). Being married was positively and marginally significantly associated with intention to use FP (β=0.524: p=0.050). Subjective normswere negatively and significantly associated with intention to use FP (β=−0.572; p=0.003) whileperceived controlwas positively associated with intention to use FP (β=0.578; p<0.0001). Education andperceived controlwere positively and significantly associated with the use of FP (respectively, β=0.422, p=0.017; and β=0.374; p=0.017), whileIntention to use FPwas positively and marginally significantly associated with the use of FP (β=0.583; p=0.052).ConclusionTPB helped understand sociocultural barriers to FP use and it can be useful to define adapted strategies in different contexts.