bluuebunny/crossref_metadata_2025_split huggingface dataset:
Computation of Roll Force and Torque in Cold-Rolling by Modern Theory
Authors: Whitton P. W. 
Published: June 2021

Abstract
The full theory for the comparison of calculated roll force and torque with experimental values is outlined. This takes into account the strip elastic compression, the derivation of the yield-stress curves in cold-rolling, and the accurate values for friction coefficient between rolls and strip. Hitherto, the contribution of each of these rolling variables has been found separately. This paper presents the combination of current theory on each. The application of this method yields results within ± 5 per cent, a much more accurate comparison than hitherto presented.
On the Stresses and Deflections of Rectangular Beams
Authors: Boley B. A. , Tolins I. S. 
Published: June 2021

Abstract
The stresses and deflections in rectangular beams and bars are calculated from the two-dimensional elasticity theory by an iterative procedure previously derived. The loading consists of either normal or shear forces varying smoothly along the span. The results are obtained in the form of infinite series, whose first terms represent the elementary solutions of strength of materials; the accuracy of the Mc/I and P/A formulas can thus be estimated. A comparison with the Timoshenko beam theory is included.
The Effect of Spring Mass on Contact-Accelerometer Responses
Authors: Lin T. H. 
Published: June 2021

Abstract
Theoretical responses of a contact-break accelerometer are analyzed for steady-state and some transient motions. The distributed mass of the spring is considered in the present analysis. For steady-state motions, viscous damping is assumed to exist between the spring and the case of the instrument. Responses to simple harmonic motions of different frequencies are shown. Responses to a single cosine wave and a step function of acceleration are analyzed. The main source of error in the contact-break accelerometer is shown to be due to the spring mass. An electromagnetic-contact accelerometer with no spring mass is proposed. Preliminary study of this accelerometer is shown.
On the Carrying Capacity of Redundant Structures
Authors: Masur E. F. , Milbradt K. P. 
Published: June 2021

Abstract
It has been shown previously (1) how the inclusion of certain nonlinear terms in the analysis of redundant trusses affects the predicted behavior of such structures in the postbuckling range. In particular, it was demonstrated that the nonlinear theory predicts states of axial stress corresponding to a general stiffening of the structure compared with the results of the classical linear analysis. After establishing a generalized minimum-strain-energy principle, this paper describes a series of tests which corroborates experimentally the predictions of the nonlinear theory. For example, the predicted (and measured) ultimate load of the test model amounts to about three times the load at which the linear theory predicts collapse through instability. A similar theory (2) dealing with the response of redundant trusses to primary bending moments is extended to certain types of singular cases which were excluded from the previous paper. It is shown analytically and verified by experiment that a constant ultimate state of axial stress may be reached already for finite applied couples. Elastic behavior is assumed throughout the paper.
Analysis of Slip Damping With Reference to Turbine-Blade Vibration
Authors: Goodman L. E. , Klumpp J. H. 
Published: June 2021

Abstract
Energy of vibration may be dissipated by microscopic slip-on interfaces where machine elements are joined in a press fit. In this paper slip damping is studied as an agent in reducing turbine-blade resonant stresses and prolonging turbine life. A general theory of slip damping is developed and an expression for the energy loss per cycle of oscillation is found. The predictions of the theory are compared with the results of controlled experiments. It appears that the theory is in satisfactory agreement with experiment and with measurements made on turbine blades elsewhere in this country and abroad. The implications of the general theory in the design of turbine blades are discussed. It appears that slip damping is capable of being an effective agent in reducing resonant stresses, especially in the “stall-flutter” condition where aerodynamic damping is inadequate. The design of a slip-damping joint which would achieve theoretically possible energy decrements much larger than are present in existing commercial construction is shown to depend on the maintenance of an optimum contact pressure.
A New Method of Analyzing Stresses and Strains in Work-Hardening Plastic Solids
Authors: Prager William 
Published: June 2021

Abstract
For work-hardening plastic solids, segmentwise linear yield conditions and the associated flow rules constitute a reasonable compromise between the mathematically convenient but physically unsound total stress-strain laws and the physically sound but mathematically inconvenient incremental laws. They allow total stress-strain laws to be used in the small, but retain the characteristic features of incremental laws in the large. The use of a segmentwise linear yield condition and the associated flow rule is illustrated by the analysis of the bending moments and deflections of a simply supported circular plate that is made of a work-hardening material and subjected to a uniformly distributed transverse load.
The Effect of Shear on the Plastic Bending of Beams
Authors: Drucker D. C. 
Published: June 2021

Abstract
The end-loaded cantilever beam of perfectly plastic material has been studied in considerable detail but many questions remain unanswered. As a first step in extension to plates, the concept is explored of an interaction curve relating limiting values of shearing force and bending moment for perfectly plastic beams. Simple illustrations demonstrate that, far more than in the elastic range, such interaction is not just a local matter but depends upon the geometry and loading of the entire beam. Useful interaction curves are obtained, nevertheless, with the aid of the upper and lower bound techniques of limit analysis, choosing the maximum-shearing-stress criterion of yielding for convenience. It is shown, in particular, that although a small amount of shear produces but a second-order reduction in the limit moment of beams, a small moment reduces the limiting shear value by a first-order term.
The Tapered-Land Thrust Bearing
Authors: Kettleborough C. F. 
Published: June 2021

Abstract
Neglecting side leakage the maximum load capacity which can be carried per unit width is obtained when there is a stepped convergence to the oil film. However, when side leakage is considered the stepped bearing is only slightly better than the tilting-pad bearing, this being due to the fact that the maximum oil pressure occurs at the step where the oil-film thickness is a maximum and hence there is easy means of escape for oil. The tapered-land bearing does not suffer from this disadvantage and computations have been carried out which show that the maximum load this bearing is capable of supporting is about 14 per cent greater than the maximum load capable of being supported by the tilting-pad bearing, both cases not neglecting side leakage. Some numerical calculations are made.
Deposition Process and Equivalent Markov Motion of High-Inertia Particles in a Long Straight Pipeline
Authors: Zhang Ri , Xu Kai , Liu Yong , Wang Yumiao 
Published: June 2021

Abstract
Two methods are used to study the process of particle deposition in a turbulent pipe flow. The Monte Carlo method tracks 10,000 particles in the turbulent pipe flow to reproduce the deposition process of the particles. The deposition velocity of the particles is determined by calculating the proportion of particles passing through the test section. The simplified deposition model uses an equivalent Markov motion instead of the radial movement of the particle in the turbulent core. The probability that a particle leaves the turbulent core depends on the radial particle position and the probability density distribution of the random vortex. The probability that a particle penetrates the boundary layer can be solved by integrating the probability density distribution of radial particle velocity. The deposition velocity of particles can be obtained by calculating the probability of an individual particle leaving the turbulent core and penetrating the boundary layer. Five experimental data series from the literature are applied to examine the predictive abilities of the two methods. The results demonstrate that the Monte Carlo method can be properly used to track the particle deposition process in the diffusion–impaction and inertia-moderated regimes. The simplified model is suitable for high-inertia particles.
Effect of the Speed Factor on the Amplitude of the Blade Passing Frequency in the Vaneless Space of a Pump Turbine in Turbine Mode
Authors: Hu Jinhong , Yang Jiebin , Zeng Wei , Yang Jiandong 
Published: June 2021

Abstract
An exponential expression describing the relationship between the amplitude of the blade passing frequency in the vaneless space of a pump turbine operating in the turbine mode and the speed factor is proposed based on statistical analysis. This mathematical relationship was discovered through signal processing of the data recorded during the emergency load rejection process of a prototype pump turbine. Subsequently, based on the pumped-storage test rig at Wuhan University, an experimental investigation was conducted to verify this mathematical relationship. The results indicated that, under the optimal guide vane opening of the model pump turbine, the goodness of fit of this mathematical relationship was quite high. As for the Francis pump turbine, the speed factor corresponds to the Strouhal number. Therefore, for this correlation, the underlying physical mechanism is the influence of the Strouhal number. This relation could inform the design and operation of pump turbines to control the intensity of pressure pulsations in the vaneless space. In addition, based on this mathematical relationship, the intensity of the rotor–stator interaction for different pump turbines can be compared quantitively.
Analysis of Flow Regimes and Associated Sources of Dissipation in Splash Lubricated Planetary Gear Sets
Authors: Boni J. B. , Changenet C. , Ville F. 
Published: June 2021

Abstract
Planetary gears are used in several applications given that they provide high reduction ratio in a compact size. Two kinds of lubrication are used in these applications: injection or splash lubrication. In case of splash lubrication, the authors already highlighted the importance of the centrifugal effects leading to the formation of an oil ring inside the reducer, therefore giving a method to compute churning power losses. In this paper, another flow regime is underlined when centrifugal forces are not sufficient to turn the oil sump into a ring. In addition to this observation, an in-depth analysis is given regarding the dependence of the churning power losses with operating conditions and oil characteristics.
A Novel Method for Fracture Pressure Prediction in Shallow Formation During Deep-Water Drilling
Authors: Yang Jin , Liu Shujie , Wang Huanhuan , Zhou Xu , Song Yu , Xie Renjun , Zhang Zhenxiang , Yin Qishuai , Xu Fei 
Published: June 2021

Abstract
Large numbers of deep-water drilling practices have shown that more than 60% of deep-water wells have complex leak-off during the drilling process, which poses great difficulties and challenges for the safety and operation time of deep-water drilling. The purpose of this article is to establish a method for predicting the fracture pressure in shallow formations. In this study, the deep-water shallow formation was divided into the upper unconsolidated soil layer, and the lower diagenetic rock layer according to the geotechnical distribution characteristics of the deep-water shallow formation. The location of the transition soil/rock layer zone was determined using the upper soil layer density trend line, and the lower rock layer density log data regression trend line. The deep-water shallow fracture pressure prediction model was established based on the soil/rock transition zone. The shear failure criterion was used above the transition zone, and the tensile failure criterion is used below the transition zone. The shallow fracture pressure of six drilled exploratory wells in the X block from the South China Sea was calculated using this new method and the calculation errors were all less than 3.18%. Moreover, the shallow fracture pressure body in this block was established using the Kriging interpolation method based on six drilled exploratory wells data. This shallow fracture pressure body established here was used to predict nine development wells shallow fracture pressure with a predictive error of less than 1.7% and there were no drilling accidents. The case study demonstrates that the new model can significantly improve the prediction accuracy has good prospects for popularization and application.
Experimental and Molecular Dynamics Simulation-Based Investigations on Hydrogen Embrittlement Behavior of Chromium Electroplated 4340 Steel
Authors: Dogan Ozge , Kapci Mehmet Fazil , Esat Volkan , Bal Burak 
Published: June 2021

Abstract
In this study, chromium electroplating process, corresponding hydrogen embrittlement, and the effects of baking on hydrogen diffusion are investigated. Three types of materials in the form of Raw 4340 steel, Chromium electroplated 4340 steel, and Chromium electroplated and baked 4340 steel are used in order to shed light on the aforementioned processes. Mechanical and microstructural analyses are carried out to observe the effects of hydrogen diffusion. Mechanical analyses show that the tensile strength and hardness of the specimens deteriorate after the chrome-electroplating process due to the presence of atomic hydrogen. X-ray diffraction (XRD) analyses are carried out for material characterization. Microstructural analyses reveal that hydrogen enters into the material with chromium electroplating process, and baking after chromium electroplating process is an effective way to prevent hydrogen embrittlement. Additionally, the effects of hydrogen on the tensile response of α-Fe-based microstructure with a similar chemical composition of alloying elements are simulated through molecular dynamics (MD) method.
Internal Training Load Affects Day-After-Pretraining Perceived Fatigue in Female Volleyball Players
Authors: Ungureanu Alexandru Nicolae , Lupo Corrado , Boccia Gennaro , Brustio Paolo Riccardo 
Published: June 2021

Purpose:The primary aim of this study was to evaluate whether the internal (session rating of perceived exertion [sRPE] and Edwards heart-rate-based method) and external training load (jumps) affect the presession well-being perception on the day after (ie, +22 h), according to age and tactical position, in elite (ie, Serie A2) female volleyball training.Methods:Ten female elite volleyball players (age = 23 [4] y, height = 1.82 [0.04] m, body mass = 73.2 [4.9] kg) had their heart rate monitored during 13 team (115 individual) training sessions (duration: 101 [8] min). Mixed-effect models were applied to evaluate whether sRPE, Edwards method, and jumps were correlated (P ≤ .05) to Hooper index factors (ie, perceived sleep quality/disorders, stress level, fatigue, and delayed-onset muscle soreness) in relation to age and tactical position (ie, hitters, central blockers, opposites, and setters).Results:The results showed a direct relationship between sRPE (P < .001) and presession well-being perception 22 hours apart, whereas the relationship was the inverse for Edwards method internal training load. Age, as well as the performed jumps, did not affect the well-being perception of the day after. Finally, central blockers experienced a higher delayed-onset muscle soreness than hitters (P = .003).Conclusions:Findings indicated that female volleyball players’ internal training load influences the pretraining well-being status on the day after (+ 22 h). Therefore, coaches can benefit from this information to accurately implement periodization in a short-term perspective and to properly adopt recovery strategies in relation to the players’ well-being status.
Genetic Polymorphisms Related to VO2max Adaptation Are Associated With Elite Rugby Union Status and Competitive Marathon Performance
Authors: Hall Elliott C.R. , Almeida Sandro S. , Heffernan Shane M. , Lockey Sarah J. , Herbert Adam J. , Callus Peter , Day Stephen H. , Pedlar Charles R. , Kipps Courtney , Collins Malcolm , Pitsiladis Yannis P. , Bennett Mark A. , Kilduff Liam P. , Stebbings Georgina K. , Erskine Robert M. , Williams Alun G. 
Published: June 2021

Purpose: Genetic polymorphisms have been associated with the adaptation to training in maximal oxygen uptake (). However, the genotype distribution of selected polymorphisms in athletic cohorts is unknown, with their influence on performance characteristics also undetermined. This study investigated whether the genotype distributions of 3 polymorphisms previously associated with training adaptation are associated with elite athlete status and performance characteristics in runners and rugby athletes, competitors for whom aerobic metabolism is important. Methods: Genomic DNA was collected from 732 men including 165 long-distance runners, 212 elite rugby union athletes, and 355 nonathletes. Genotype and allele frequencies of PRDM1 rs10499043 C/T, GRIN3A rs1535628 G/A, and KCNH8 rs4973706 T/C were compared between athletes and nonathletes. Personal-best marathon times in runners, as well as in-game performance variables and playing position, of rugby athletes were analyzed according to genotype. Results: Runners with PRDM1 T alleles recorded marathon times ∼3 minutes faster than CC homozygotes (02:27:55 [00:07:32] h vs 02:31:03 [00:08:24] h, P = .023). Rugby athletes had 1.57 times greater odds of possessing the KCNH8 TT genotype than nonathletes (65.5% vs 54.7%, χ2 = 6.494, P = .013). No other associations were identified. Conclusions: This study is the first to demonstrate that polymorphisms previously associated with training adaptations in nonathletes are also associated with marathon performance (PRDM1) and elite rugby union status (KCNH8). The genotypes and alleles previously associated with superior endurance-training adaptation appear to be advantageous in long-distance running and achieving elite status in rugby union.
Combined Synthesis and Hydroprocessing of Hydrocarbons over Co/SiO2 + ZSM-5 + Al2O3 Catalysts Promoted by Nickel
Authors: Yakovenko R. E. , Zubkov I. N. , Bakun V. G. , Savost’yanov A. P. 
Published: June 2021

AbstractThe study investigates the effects of nickel introduction methods on the properties of a hybrid cobalt catalyst in a combination of Fischer–Tropsch synthesis and the hydroprocessing of the synthesized products. At 240°C, 2 MPa, and syngas WHSV 1000 h–1, the catalytic performances were compared, the products were analyzed for the hydrocarbon and fractional compositions, and the characteristics of the synthesized fuels were determined. Among the catalysts differing in nickel introduction method, the sample with a nickel-containing zeolite component prepared by ion exchange was found to have the highest hydrogenation activity, while the sample with a metal component generated by joint cobalt/nickel introduction [Co/SiO2+ Ni(i)/HZSM-5 + Al2O3] exhibited the highest isomerization activity.
Punctual Categoricity Relative to a Computable Oracle
Authors: Kalimullin I. Sh. , Melnikov A. G. 
Published: June 2021

Abstract
We are studying the punctual structures, i.e., the primitive recursive structures on the whole set of integers. The punctual categoricity relative to a computable oracle $$f$$ means that between any two punctual copies of a structure there is an isomorphism which togeteher with its inverse can be derived via primitive recursive schemes augmented with $$f$$. We will prove that the punctual categoricity relative to a computable oracle can hold only for finitely generated or locally finite structures. We will show that the punctual categoricity of finitely generated structures is exhaused by the computable oracles with primitive recursive graph. We also present an example of locally finite structure where the punctual categoricity is provided by a primitive recursively bounded computable oracle.
Catatonic syndrome as the presentation of encephalitis in association with COVID-19
Authors: Vazquez-Guevara Damaris , Badial-Ochoa Sandra , Caceres-Rajo Karen M , Rodriguez-Leyva Ildefonso 
Published: June 2021

COVID-19 has shown different neurological manifestations even sometimes there are the initial or the main presentation.The following case report is about a middle-aged woman who, over 3 days, developed fever, clinical neurological alterations (stupor, muteness, fixed gaze and catatonia), cerebrospinal fluid (16 lymphocytes) and an electroencephalogram (EEG) (4–6 Hz generalised activity) with characteristics of encephalitis. A serum IgG, IgM, nasopharyngeal swab PCR for SARS-CoV-2. The patient responded positively to support measures, symptomatic and corticosteroid treatment. At discharge, the patient was independent and improved considerably.We report the presence of catatonia as a possible and atypical manifestation of encephalitis in association with COVID-19.
Is there scope to improve the selection of patients with alcohol-related liver disease for referral to secondary care? A retrospective analysis of primary care referrals to a UK liver centre, incorporating simple blood tests
Authors: Rhodes Freya Alison , Cococcia Sara , Patel Preya , Panovska-Griffiths Jasmina , Tanwar Sudeep , Westbrook Rachel H , Rodger Alison , Rosenberg William 
Published: June 2021

ObjectivesTwenty per cent of people with alcohol use disorders develop advanced fibrosis and warrant referral to secondary care. Improving outcomes in alcohol-related liver disease (ArLD) relies on its earlier detection in primary care with non-invasive tests (NIT). We aimed to determine the proportion of alcohol-related referrals who were diagnosed with advanced fibrosis in secondary care, the prevalence of both alcohol and fatty liver disease (‘BAFLD’) and the potential impact of NIT on referral stratification.Design/settingRetrospective analysis of all general practitioner-referrals with suspected ArLD/non-alcoholic fatty liver disease (NAFLD) to a UK hepatology-centre between January 2015 and January 2018.ParticipantsOf 2944 new referrals, 762 (mean age 55.5±13.53 years) met inclusion criteria: 531 NAFLD and 231 ArLD, of which 147 (64%) could be reclassified as ‘BAFLD’.Primary outcome measureProportion of referrals with suspected ArLD/NAFLD with advanced fibrosis as assessed by tertiary centre hepatologists using combinations of FibroScan, imaging, examination and blood tests and liver histology, where indicated.Secondary outcome measuresIncluded impact of body mass index/alcohol consumption on the odds of a diagnosis of advanced fibrosis, and performance of NIT in predicting advanced fibrosis in planned post-hoc analysis of referrals.ResultsAmong ArLD referrals 147/229 (64.2%) had no evidence of advanced fibrosis and were judged ‘unnecessary’. Advanced fibrosis was observed in men drinking ≥50 units per week (U/w) (OR 2.74, 95% CI 1.51 to 5, p=0.001) and ≥35 U/w in women (OR 5.11, 95% CI 1.31 to 20.03, p=0.019). Drinking >14 U/w doubled the likelihood of advanced fibrosis in overweight/obesity (OR 2.11; 95% CI 1.44 to 3.09; p<0.001). Use of fibrosis 4 score could halve unnecessary referrals (OR 0.50; 95% CI 0.32 to 0.79, p=0.003) with false-negative rate of 22%, but was rarely used.ConclusionsThe majority of referrals with suspected ArLD were deemed unnecessary. NIT could improve identification of liver damage in ArLD, BAFLD and NAFLD in primary care. Anecdotal thresholds for harmful drinking (35 U/w in women and 50 U/w in men) were validated. The impact of alcohol on NAFLD highlights the importance of multi-causality in chronic liver disease.