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This study applies House's (1996, 2005) dimensions of cross-cultural differences as a diagnostic tool to investigate regional variation regarding two pragmalinguistic requestive patterns with may in Scottish and English non-private letters (1500 to 1700). The dimensional scheme proves a useful tool for explaining similarities and differences in the requestive behaviour in the two varieties. It is shown that, in the sixteenth century, grounders with may are part of a set of downgrading devices employed by letter-writers to counteract the directness and self-orientation particularly of performative requests in both the Scottish and the English correspondence. Moreover, the dimensional analysis explicates the cross-varietal differences regarding may in the seventeenth century correspondence by linking the rise of mitigating may in performative requests in the Scottish letters to the increased self-orientation towards the letter-writer, which is not counter-balanced by other downgraders. [ABSTRACT FROM AUTHOR]

Weirs are hydraulic constructions typically employed in dam spillways and channel control structures. The shape and size of the crest will determine whether the weir is linear or nonlinear. Of the two types, non-linear weirs are often selected due to their ability to allow different discharge levels at the minimal heads. A recently introduced variation of the nonlinear kind is the piano key weir. This research undertakes a comprehensive analysis of the hydraulic functionality of the type-C piano key weir under conditions of free flow. The research methodology involved modifying the models by adding stages to the sides and monitoring the effect on the efficacy of discharge, represented by the discharge coefficient. The study further extrapolated formulae linking critical variables to the discharge coefficient, using dimensional analysis and SPSS software. The findings of this study revealed that the introduction of stages significantly bolstered the discharge coefficient in the altered models compared to the standard model. This enhancement was reflected in a 6% and 11% ascent with length expansion of the stages and a 6% and 8% rise with height increase of the stages. Additionally, the model's performance was augmented with a drop in the total head ratio. [ABSTRACT FROM AUTHOR]

The purpose of this research is to create and develop a conceptual model for digital transformation in urban management organizations such as municipalities and especially Karaj municipality. In terms of purpose, the present research is applied and the type of research is descriptive-exploratory. Also, information gathering is included in documentary and survey research. The findings of the research showed that 8 main and 27 research sub-criteria were identified during the fuzzy Delphi method in the implementation of digital transformation, and in the next step, their weight and rank were determined using the dimensional chain analysis (AHP) method. These are, in order of weight: digital transformation infrastructure, organizational transformations, digital investment, digital change tools, digital digital experiences, Global digital innovation and developments, digital thinking, digital knowledge management. Also, according to the findings of interpretive structural models in 5 levels, it has the quality that organizational changes and digital investment are placed at the first level and the prerequisites of digital change in Karaj municipality are numbered. Digital transformation infrastructures along with organizational transformations and investment in the field of digital transformation are considered as the most important influencing features in the implementation of digital transformation in Karaj municipality. This is the concept that considering the nature of Karaj Municipality's service provision, other urban management organizations and municipalities of the country can also take advantage of this research in the digital transformation of their organization. [ABSTRACT FROM AUTHOR]

Stellite alloys have good wear resistance and maintain their strength up to ~ 600°C, making them suitable for various industrial applications like cutting tools and combustion engine parts. This investigation was aimed at i) manufacturing new Stellite alloy blends using powder metallurgy and ii) mathematically mapping hardness, yield strength, ductility and impact energy of base and alloy blends. Linear, exponential, polynomial approximations and dimensional analyses were conducted in this semi-empirical mathematical modelling approach. Base alloy compositions similar to Stellite 1, 4, 6, 12, 20 and 190 were used in this investigation to form new alloys via blends. The microstructure was analysed using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). Mechanical performance of alloys was conducted using tensile, hardness and Charpy impact tests. MATLAB® coding was used for the development of property maps. This investigation indicates that hardness and yield strength can be linked to the wt.% composition of carbon and tungsten using linear approximation with a maximum variance of 5% and 20%, respectively. Elongation and carbide fraction showed a non-linear relationship with alloy composition. Impact energy was linked with elongation through polynomial approximation. A dimensional analysis was developed by interlinking carbide fraction, hardness, yield strength, and elongation to impact energy. [ABSTRACT FROM AUTHOR]

This article recovers an important, century-old debate regarding the methodological and metaphysical foundations of dimensional analysis. Consideration of Richard Tolman's failed attempt to install the principle of similitude—the relativity of size—as the founding principle of dimensional analysis both clarifies the method of dimensional analysis and articulates two metaphysical positions regarding quantity dimensions. Tolman's position is quantity dimension fundamentalism. This is a commitment to dimensional realism and a set of fundamental dimensions that ground all further dimensions. The opposing position, developed primarily by Percy Bridgman, is quantity dimension conventionalism. Conventionalism is an antirealism regarding dimensional structure that holds our nonrepresentational dimensional systems to have basic quantity dimensions fixed only by convention. This metaphysical dispute was left somewhat unsettled. It is shown here that both of these positions face serious problems: fundamentalists are committed to surplus dimensional structure; conventionalists cannot account for empirical constraints on our dimensional systems or the empirical success of dimensional analysis. I show that an alternative position saves what is right in both: quantity dimension functionalism. [ABSTRACT FROM AUTHOR]

The development of natural fibers in engineering applications requires an accurate measurement of their dimensional characteristics and mechanical properties. Fiber cross-sectional area (CSA) obtained from lateral dimensional measurements should consider the specific cross-sectional shape (CSS) of the fibers and their wide lengthwise variations. In this study, the dimensional measurements of water-retted and unretted sisal fibers were conducted by laser scanning microscopy (LSM) and calculation-based methods. Single fiber tensile tests were performed using the digital image correlation (DIC) method. Results show that the diameters of water-retted and unretted fibers measured by LSM were 233 ± 45 µm and 236 ± 42 µm, respectively. The diameters of water-retted and unretted fibers obtained by calculation were 192 ± 17 µm and 178 ± 20 µm, respectively. The tensile strengths of water-retted and unretted fibers were 679 ± 118 MPa and 718 ± 106 MPa, respectively. The strain at failure and elastic modulus of water-retted and unretted fibers were 2.0 ± 0.6% and 34 ± 8 GPa, as well as 1.5 ± 0.2% and 48 ± 6 GPa, respectively. Water retting seems to predominantly influence the strain at failure and elastic modulus of sisal fibers, as confirmed by the ANOVA analysis.

Water distribution uniformity is important for assessing the hydraulic performance of sprinkler nozzles and designing sprinkler irrigation systems. However, current studies rarely consider the redistribution abilities of sprinkler water in the soil and judge whether a sprinkler system is qualified based only on the coefficient of uniformity on the ground (CUg), which leads to a serious underestimation of the actual irrigation effect of sprinkler irrigation projects. Hence, this study establishes and validates a COMSOL-3D model to simulate the movement of soil water during sprinkler irrigation. Moreover, the effects of the soil hydraulic and irrigation parameters on the coefficient of soil moisture content uniformity (CUs) were explored. The results showed that 1) the Nash-Sutcliffe efficiency coefficient (NSE) of the vertical wetting front (VWF) and soil moisture content (SMC) in the two sets of validation experiments was 0.965 and 0.862 and 0.867 and 0.900, respectively. 2) Owing to the differences in soil saturated hydraulic conductivity, after the end of irrigation, the VWF transport rates in vertical direction differed among the three textured soils, with loam exhibiting the highest rate, followed clay loam and silty clay. However, their CUs increased with increasing water transport time, indicating that the water distribution within the sprinkler-wetted zone became increasingly homogeneous as the sprinkler irrigation water was transported and diffused from the top to bottom in the soil. 3) Dimensional analyses showed that CUs were strongly influenced by the initial soil moisture content, irrigation time, and water transport time. 4) In Case 4, when CUg was reduced from 81.9 % to 60 %, CUs only decreased from 83.2 % to 81.4 % after 48 h of irrigation, indicating that the sprinkler irrigation water had good redistributive ability. This study provides a reference for rationally reducing the CUs of sprinkler irrigation projects and maximising project investments and planting interest.

This study utilizes numerical simulations and dimensional analysis to investigate the impact of the two-phase outlet on flow field characteristics and separation efficiency of the separator. The study revealed a boundary layer separation at the water outlet, which was subsequently addressed to reduce energy losses in the separator. Dimensional analysis considered the influences of operational, structural, and physical parameters on the separator's performance. With other structural parameters held constant, separation efficiency is directly proportional to the ratio of inlet and oil-outlet diameter. Additionally, the separation efficiency is also associated with Re and the ratio of the inlet to the water-outlet diameter. When the diameter of the water outlet is constant, the axial vortex separator achieves optimal separation when the ratio of inlet and water-outlet diameter is 0.563, with a maximum separation efficiency of 97.00%. The optimal separation efficiency is reached at Re=22,908 under various operational conditions. Separation efficiency increases with water content, peaking at an inlet water content of 0.9 across different structural parameters. Separation efficiency shows an increase followed by a decrease with the rise in inlet flow rate(vi), achieving the best performance at vi=3m/s for the different separator structures studied.

In this study, we conduct a theoretical and numerical analysis of one dimensional thermoelastic Timoshenko system with the three-phase-lag (TPL) heat conduction model. Theoretically, we establish the existence and uniqueness of the solutions using the well-known Lumer-Phillips theorem. Applying the energy method, we introduce a new stability number ϰ. Then, with assumptions on the phase-lag parameters τ q , τ ν and τ θ proposed by the TPL model, we prove the exponential stability of solutions when ϰ = 0. Numerically, we present a study based on a backward Euler scheme and a finite element method. Subsequently, by imposing additional regularity on the solution, we obtain some a priori error estimates. Finally, expository examples and simulations are presented to demonstrate the availability of the main results. [ABSTRACT FROM AUTHOR]

General derivation of the well-known Ren–Otsuka relationship, 1 α d T o d x = − α β (where T o , x, α and β (> 0) are the transformation temperature and composition, as well as the composition and temperature coefficient of the critical shear constant, c′, respectively) for shape memory alloys, SMAs, is provided based on the similarity of interatomic potentials in the framework of dimensional analysis. A new dimensionless variable, t o x = T o x T m x , describing the phonon softening (where Tm is the melting point) is introduced. The dimensionless values of the heat of transformation, ΔH, and entropy, ΔS, as well as the elastic constants c′, c44, and A = c 44 c ′ are universal functions of to(x) and have the same constant values at to(0) within sub-classes of host SMAs having the same type of crystal symmetry change during martensitic transformation. The ratio of d t o d x and α has the same constant value for all members of a given sub-class, and relative increase in c′ with increasing composition should be compensated by the same decrease in to. In the generalized Ren–Otsuka relationship, the anisotropy factor A appears instead of c′, and α as well as β are the differences between the corresponding coefficients for the c44 and c′ elastic constants. The obtained linear relationship between h and to rationalizes the observed empirical linear relationships between the heat of transformation measured by differential scanning calorimetry (DSC) (QA⟶M) and the martensite start temperature, Ms. [ABSTRACT FROM AUTHOR]

According to the available literature, the morphometric characteristics of badland basins (e.g., area of the badland drainage basin, A, and actual eroded badland area, AE) can be used for deducing an empirical model able to predict the eroded volume, V. The main aim of this investigation is to implement a model to estimate the volume of eroded sediments, which uses widely applied morphological indices. This model, deduced by applying dimensional analysis and self‐similarity theory, was calibrated and verified using the badland morphometric characteristics of five datasets (four available in the literature and one presented in this investigation). The results showed that the estimate of the eroded volume is reliable only for the data characterized by V/A values higher than a threshold (0.1 m) corresponding to the vertical resolution of the investigated digital terrain models (DTMs). For considering that the actual eroded badland area AE can be different from the respective drainage area A, as badland erosion induces a headward extension, the model for estimating the eroded volume was calibrated by differentiating between partially (AE/A < 1) and totally (AE/A = 1) eroded badland basins. The analysis highlighted that the actual eroded badland area, which is the area that more contributes to the active erosion process, remarkably influences the estimate of V, and the inclusion of the ratio AE/A in the model is useful to improve this estimate. The estimate of the eroded sediment volume from calanchi areas has a scientific and practical relevance as the high erosion rates of small badland areas can disproportionately contribute to the basin‐scale sediment budget. [ABSTRACT FROM AUTHOR]

Featured Application: Additive Manufacturing (AM) represents new and very promising manufacturing processes. The results can be applied immediately in the manufacturing industry in order to obtain significant decreases of the costs in some specific domains. By means of its facilities, AM brings several advantages in comparison with the classical manufacturing technologies. Nowadays, there are a huge number of unexplored directions, which assure AM will become a very powerful manufacturing process in the next period, with an undoubted low cost and reduced material consumption, as well as optimal stiffness and competitiveness technology. Between the unexplored (or less-explored) directions, one has to mention the dimensional methods' involvement in gaining an optimal, highly competitive final product. This means that instead of the real structural element, named the prototype, the engineers will perform high-accuracy tests on the attached reduced-scale models, whose experimental results are extended to the prototype by means of the deduced model law (ML). The authors, based on their previous theoretical research as well as experimental investigations, offer a new approach, which is less implemented in AM technologies. Based on the obtained results, these dimensional methods are very promising, especially the last one, the so-called Modern Dimensional Analysis (MDA), conceived by Thomas Szirtes and described in the following paper. Starting with the nowadays-applied dimensional methods' critical analysis, the authors will present evidence for the advantages of MDA, especially on the polymer-based AM technology. They will prove that MDA represents a very promising, as well as easy approach, which through its implementation can offer a higher competitiveness for AM technologies. As an illustration of the advantages of MDA, the authors conceived several MDA approaches for a given structural element's case (a cantilever beam, with an internal-ribbed structure loaded at its free end by means of a vertical concentrated load), which, through their high accuracy in experimental-validated MLs, offer very good accuracy in model–prototype correlation. The deviations between the effective measured values of the displacements on the prototypes and those predicted, based on the values of the measurements on the models assigned to the prototypes by the validated MLs, were 1.06, 1.60, and 2.35%, respectively. In the authors' opinion, MDA can represent a starting point for conceiving a highly competitive product with an optimal filling, as well as the deposition of layers using AM technologies. Based on the authors' best knowledge, up to this moment, it seems that this engineering area does not fully apply the advantages of MDA, only in few limited cases, analyzed in the following. [ABSTRACT FROM AUTHOR]

We present an innovative approach to dimensional analysis, referred to as augmented dimensional analysis and based on a representation theorem for complete quantity functions with a scaling-covariant scalar representation. This new theorem, grounded in a purely algebraic theory of quantity spaces, allows the classical π theorem to be restated in an explicit and precise form and its prerequisites to be clarified and relaxed. Augmented dimensional analysis, in contrast to classical dimensional analysis, is guaranteed to take into account all relations among the quantities involved. Several examples are given to show that the information thus gained, together with symmetry assumptions, can lead to new or stronger results. We also explore the connection between dimensional analysis and matroid theory, elucidating combinatorial aspects of dimensional analysis. It is emphasized that dimensional analysis rests on a principle of covariance. [ABSTRACT FROM AUTHOR]

In this article, a strategy is proposed to prepare highly toughened composites from polypropylene (PP), rice husk charcoal (RHC) and glycidyl methacrylate (GMA)-modified EPDM using melt blending and hot pressing. The structure of GMA-modified EPDM is confirmed by Fourier transform infrared spectroscopy (FTIR). The influences of the amounts of EPDM and GMA-modified EPDM on PP composites are investigated by virtue of mechanical properties testing, dimensional stability analysis, thermogravimetric analysis (TGA), X ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicate that the incorporation of GMA-modified EPDM significantly improves the toughness of PP composites and compared to PRHC the impact strength of PRKEG10 is up to the value of 537 J/m and increases by 555%, concurrently the tensile strength and modulus exhibit less decrease with the value of 8.22 MPa and 353 MPa, respectively. Shrinkage measurements show the dimensional change rates of length, width, and height decrease from 3.2%, 2.9%, and 3.3% to 1.73%, 1.46%, and 1.93%, respectively, improving the dimensional stability of PP composites. SEM reveals that shear yield and cavitation during the loading process lead to the excellent toughness of PP composites. This strategy provides a novel route to fabricate high ductility rice husk charcoal-based PP composites and expand certain industrial application. [ABSTRACT FROM AUTHOR]

This research proposes a parameter scaling method for dimensional analysis in extreme maneuver scenarios. Scaled vehicle experiments using dimensional analysis offer advantages in terms of test location, driver safety, and cost savings. Previous studies have overlooked the nonlinear effects of tires in dimensional analysis. Two methods are presented: scaling the frictional coefficient between tires and surfaces and virtual scaling of gravitational acceleration through time scaling. The methods were validated using a 1/8 scaled vehicle and the CarSim software program. This research establishes a practical and valid approach to parameter scaling in vehicle dynamics, considering tire nonlinearity and accommodating extreme maneuvers. [ABSTRACT FROM AUTHOR]

10.1119/5.0133767.1 Timescales spanning 24 orders of magnitude smaller than one second can be studied experimentally, and each range is packed with different physical phenomena. This rich range of timescales offers a great context for an innovative undergraduate physics course which introduces modern physics and technology from an unconventional perspective. Based on the author's experience in lecturing on these topics to different audiences, this paper proposes a syllabus of a semester-long timescale-based undergraduate physics course. Editor's Note: Did you know that state-of-the-art experiments could measure timescales down to a few rontoseconds (such things do actually exist and correspond to 10 − 27 s)? In the spirit of Physics for Future Presidents, this paper uses the theme of fast timescales to build a semester-long syllabus to introduce undergraduate science majors to various physics concepts, ranging from condensed matter to particle physics, and to examples of commonly used technology (ink-jet printing, ultrasound imaging, high-speed cameras, etc.). Such a course could also be used for outreach, and it emphasizes the use of dimensional analysis and orders of magnitude. [ABSTRACT FROM AUTHOR]

Aim: To analyze toxic positivity and its relevance to nursing. Design: Concept analysis using Schatzman's dimensional analysis approach. Data Sources: Two searches were conducted using Google Scholar, JSTOR, ProQuest and CINAHL (1990–2023). Keywords included "toxic positivity" (Phase 1) and "emotional suppression," "unrealistic optimism"; "disingenuous happiness," "forced gratitude" and "logical fallacy" (Phase 2). Retained sources (1) were in English (Phases 1 and 2); (2) used 'toxic positivity' as a construct reflecting the purpose of analysis (Phase 1); and (3) demonstrated relevance towards analytical findings (Phase 2). Total analytic sources were 35. Methods: The analytic phase, identification, elucidated conceptual dimensions and contexts. The analytic phase, logistics, examined relationships among dimensions and contexts through an iterative process resulting in a dimensional matrix/conceptual model. Results: Salient dimension is Emotional Suppression with two sub‐dimensions, Logical Fallacy and Forced Gratitude. Other dimensions include Unrealistic Optimism and Disingenuous Happiness. Contexts include intra‐ and post‐paradigmatic societal shifts and intra‐ and post‐traumatic experiences. Analysis reveals toxic positivity as an exchange between a giver and receiver with the receiver experiencing negative outcomes. Conclusion: The concept appears consistent in its application and use across contexts and is emerging in nursing literature. Implications for the Profession: Acknowledging toxic positivity in nursing may inform theoretical and future research related to improving nursing burnout, bolstering retention, and enhancing well‐being. Nurses across work environments may encounter toxic positivity. Leaders should consider policy adoption and inclusion of trauma‐informed practices. Impact: Nursing workforce issues require deeper examination of potential contributing factors. Findings suggest toxic positivity may be encountered in work environments impacting nursing at individual and system levels. Patient or Public Contribution: No patient or public contribution. [ABSTRACT FROM AUTHOR]

The resistance characteristics of the volatile gases in the packed bed of petroleum coke in the vertical shaft calciner is key to whether the volatiles can escape smoothly. This study first systematically investigated the physical parameters of petroleum coke, such as porosity and bulk density, through experimental testing methods. Secondly, an experimental device for measuring the pressure drop in the packed bed of petroleum coke was constructed. Based on this, the study explored the influence of material layer height, bed diameter ratio, particle size, and gas flow rate on the pressure drop of the bed. The research results show that as the particle size of petroleum coke increases, the bulk density decreases, and the porosity increases. When the bed diameter ratio D/dP > 20, the wall effect can be ignored. The unit pressure drop is positively correlated with the gas flow rate and negatively-correlated with the particle size. The dimensionless relationship for the resistance of the accumulated coke layer is f=6.922 × 1060e86,519 (1 一 e)105,1394 Re-1.047 . This study provides theoretical support for understanding the behavior of volatile gases during the calcination of petroleum coke in a vertical shaft calciner. [ABSTRACT FROM AUTHOR]

In nature and engineering, fluid movements involving swirling patterns, or vortices, are common occurrences. Some flows involve free-surface vortices that can potentially lead to a phenomenon termed gas entrainment (GE). There is no validated tool that can predict the free-surface profile of the gas core prior and subsequent to the GE. This study focuses on experimental and numerical investigation of flows with unsteady free-surface vortices that can potentially lead to gas entrainment. An extensive experimental work, performed in a dedicated experimental setup built in the present study, yields two main contributions. First, a new GE onset criterion, based on implementing dimensional analysis to the experimental results, is developed. The onset criterion is found to be suitable also for other experiments in the literature. Second, the experimental acquisition of the free-surface profiles, obtained with a high-speed camera, is used for validating the numerical approach. This three-dimensional numerical tool incorporates Large Eddy Simulation to capture turbulence, with Volume-of-Fluid approach to simulate free-surface profiles. The model predicts with high accuracy the free-surface profiles in cases with and without GE, observed experimentally. Then, the detailed simulation results for this type of flows are analyzed quantitatively for the first time in the available literature, using radial, axial, and tangential velocity components. The present study sheds new light on free-surface vortex flows, in general. The experimental and numerical achievements in this study can serve as a tool both to predict the free-surface flow profiles with high accuracy and to prevent gas entrainment in the engineering systems. [ABSTRACT FROM AUTHOR]

Knowing the respiration rate of fresh products during storage is very important. One can use direct measurement or available prediction equations to determine the respiration rate. However, the availability of the prediction equations still needs to be improved. This study aims to develop mathematical models of respiration rate for pretreated bell peppers during hypobaric storage. Model development was done by applying dimensional analysis. Mature green bell peppers were used as the experimental samples. Three pretreatments on the bell pepper before storage, namely control, ozone pretreatment, and UV-C pretreatment, combined with three hypobaric storage levels of 26, 64, and 101 kPa, were studied. An apparatus set was built to create hypobaric conditions. An ozone generator and UV-C lamp were used to apply pretreatments to the samples. It was found that respiration rate models could be developed by considering bell pepper surface area, weight, volume, storage time, storage volume, and pressure. At the storage pressures of 101 to 56 kPa, UV-C pretreatment was the best in suppressing the respiration rate of bell pepper. Meanwhile, at a storage pressure of 26 kPa, the application of ozone and UV-C pretreatment gave a higher respiration rate than the control. The three models were found to have different characteristics and showed high accuracy with the experimental results. The dimensionless product of π3 was found to have the most significant effect on RCO2 for the three models. This finding indicated that the ratio between bell pepper and jar volumes is critical to ensure the model works. [ABSTRACT FROM AUTHOR]

Natural fibre in cement matrix was used to reinforce, increase tensile strength, and protect against matrix cracking. The various properties of the matrix, which were introduced by the shrinkage and thermal stresses, can be attributed to the microcracks on the composites. The composites experienced significant negative changes due to the spread of microcracks. Changes in moisture have an impact on the dimensional stability of cement-bonded fibreboards. The increasing moisture content caused the expansion of cement-bonded fibreboard, whereas shrinkage was caused by the moisture being evaporated. Since natural fibres connect ineffectively with the cement matrix due to their hydrophilicity, fibre-cement composites are dimensionally unstable. Hot water treatments operate by clearing the fibre's surface of volatile compounds, impurities, and waxy elements and facilitating water absorption. Numerous variables, including the mixing ratio, the targeted density, and the pre-treatment technique used on natural fibre, influence the dimensional stability of cement-bonded fibreboard. The compatibility of cement-bonded fibreboard increases with increasing cement/fibre mixing ratio, density of cement-bonded fibreboard, hot water treatment temperature and duration. [ABSTRACT FROM AUTHOR]

In continuum mechanics (especially in hydroaeromechanics), methods of modeling flow (deformation) by characteristic numbers are widely used. The present study is devoted to the search for characteristic combinations of constitutive thermoelastic modules, geometric and thermomechanical parameters of the boundary value problem. Modeling the micropolar solids deformation by characteristic numbers is characterized by a sufficiently large number (13) of constitutive modules. The constitutive equations, the dynamic equations and the heat conduction equation for a semi-isotropic micropolar thermoelastic continuum are derived in a linear approximation. A dimensional analysis of the governing system of differential equations is carried out. A physically consistent sets (9 primary and several arbitrary) of dimensionless characteristic combinations of constitutive constants is proposed. The characteristic numbers for harmonic waves propagating along the axis of a stress free thermally insulated long cylindrical semi-isotropic thermoelastic waveguide are obtained and discussed. [ABSTRACT FROM AUTHOR]

To achieve high precision and repeatability of prototyped models, work is carried out to improve existing solutions and thus expand the areas of application of 3D printers. Ways to increase the efficiency of 3D printing are being sought. The subject of the work concerns the analysis of dimensional and shape accuracy and repeatability of samples produced by a technology based on layered extrusion of thermoplastic polymers using FFF—fused filament fabrication technology. The key parameter for assessing the quality of parts is the property most expected by 3D printer users regarding the accuracy of dimensions of manufactured prototypes. As part of the research, conclusions were drawn regarding the precision of the samples as original patterns. The dimensional accuracy in the x, y, and z axes of the 3D printer was determined in terms of the design of the 3D printer's actuator system. Three-dimensional maps of deviations of the pattern surface were used in relation to the nominal 3D CAD model to test the accuracy. The analytical results obtained during the research work, together with the graphs of the normal distribution probability function, indicate a high repeatability for each of the axes, and the highest repeatability was for the z-axis. The dimensions in the remaining axes were within the assumed tolerance of 0.1 mm, except for the two extreme dimensions, which were caused by a different method of heat dissipation, proving the influence of the arrangement of samples on the working platform. [ABSTRACT FROM AUTHOR]

We consider a low-energy effective theory of p -branequaes in a D -dimensional spacetime, and impose two conditions: (1) the theory is scale-invariant, and (2) the electric–magnetic dual |$(D-p-4)$| -branes exist and they obey the same type of interactions to the p -branes. (We also assume other natural conditions such as Lorentz invariance but not string theory, supersymmetry, supergravity, and so on.) We then ask what values of p and D are consistent with these conditions. Using simple dimensional analysis, we find that only two solutions are possible: |$(p,D)=(2,11)$| and |$(p,D)=(2n-1,4n+2)$|⁠ , (⁠|$n=1,2,3,\cdots$|⁠). The first solution corresponds to M-theory, and the second solutions at |$n=1$| and |$n=2$| correspond to self-dual strings in little string theory and D3-branes in type IIB superstring theory, respectively, while the second solutions for |$n \ge 3$| are unknown but would be higher spin theories. Thus, quantum gravity (massless spin two theory) satisfying our two conditions would only be superstring theories, and the conditions would be strong enough to characterize superstring theories in quantum gravity. [ABSTRACT FROM AUTHOR]

The joint of longitudinally connected slab track is vulnerable to damage from environmental impacts and repeated train loads. Under high temperature environments, the joint becomes a high risk area for track slab upwarp, which significantly affects the upwarp stability of the track slab and the safe operation of trains. This study employs the arc length approach and a finite element model to investigate the upwarp equilibrium development path of the track slab, the upwarp evolution process of the track slab under the joint damage is further analyzed. Then, the influence of different initial defects on the vertical stability of the track slab is studied. Utilizing dimensional analysis, a general formula for calculating the critical temperature rise of the track slab is proposed. The results are as follows: (1) The entire upwarp process of track slab under joint damage can be divided into three stages: stability, upwarping development, and instability. (2) A nonlinear correlation exists between the upwarp critical temperature rise of the track slab and three types of initial defects. Height defects in narrow joints exert the most significant impact on the critical temperature rise, followed by initial Out-of-straight (initial OOS), with the initial bending shape having the least effect. The complete defect of the narrow joint reduces the upwarp critical temperature rise of the track slab by 53.26°C, a 48.4% reduction. (3) A unified expression, derived from the characteristic parameters of initial defects and dimensional analysis, can more accurately predict the upwarp critical temperature rise of the track slab. [ABSTRACT FROM AUTHOR]

Due to its exceptional mechanical properties, 18CrNiMo7-6 alloy steel is one of the preferred materials for producing critical components, such as high-speed heavy-duty gearboxes. To study the relationship between cylindrical grinding parameters (e.g., workpiece speed, wheel speed, and grinding depth) and responses (i.e., grinding force, temperature, and surface residual stress), dimensional analysis and finite element simulation of cylindrical grinding were performed in this paper. A mathematical model for predicting the grinding force and residual stress of cylindrical grinding was proposed, and numerical and experimental verifications of cylindrical 18CrNiMo7-6 alloy steel were carried out. The numerical verification results showed that the maximum relative errors of the model for predicting the grinding force and residual stress were 7.9% and 11.2%, respectively. The experimental results revealed that the maximum absolute errors were 1.31 N and 33.7 MPa, respectively. To consider the simplification between finite element simulation and experiments, a modified model was proposed, with the errors of 5.4% and 8.6% for grinding force and residual stress, respectively. The results of this study indicate that the proposed model can guide practical grinding operations and help optimize machining parameters, improve production efficiency, and achieve high-quality machining results. [ABSTRACT FROM AUTHOR]

Abstract.In this work, we consider the discriminant analysis under the weak sparsity where many entries of the parameters are nearly zero. We develop a unified LASSO-typed framework to estimate the parameters for sparse discriminant analysis and derive the general non asymptotic error bound under the weak sparsity condition. As applications, we revisit the sparse linear discriminant analysis and sparse quadratic discriminant analysis. We establish the consistency of the estimators and also the misclassification error rate. These results extend the sparse discriminant analysis methods to weak sparsity setting and refine the existing theoretical results. [ABSTRACT FROM AUTHOR]

Machine learning interatomic potential (MLIP) has been widely adopted for atomistic simulations. While errors and discrepancies for MLIPs have been reported, a comprehensive examination of the MLIPs' performance over a broad spectrum of material properties has been lacking. This study introduces an analysis process comprising model sampling, benchmarking, error evaluations, and multi-dimensional statistical analyses on an ensemble of MLIPs for prediction errors over a diverse range of properties. By carrying out this analysis on 2300 MLIP models based on six different MLIP types, several properties that pose challenges for the MLIPs to achieve small errors are identified. The Pareto front analyses on two or more properties reveal the trade-offs in different properties of MLIPs, underscoring the difficulties of achieving low errors for a large number of properties simultaneously. Furthermore, we propose correlation graph analyses to characterize the error performances of MLIPs and to select the representative properties for predicting other property errors. This analysis process on a large dataset of MLIP models sheds light on the underlying complexities of MLIP performance, offering crucial guidance for the future development of MLIPs with improved predictive accuracy across an array of material properties. [ABSTRACT FROM AUTHOR]

Sweetpotato is an economically important crop, and it has various advantages over other crops in addressing global food security and climate change. Although substantial articles have been published on the research of various aspects of sweetpotato biology, there are no specific reports to systematically crystallize the research achievements. The current review takes the lead in conducting a keyword-centric spatiotemporal dimensional bibliometric analysis of articles on sweetpotato research using CiteSpace software to comprehensively clarify the development status, research hotspot, and development trend in the past 30 years (1993-2022). Quantitative analysis was carried out on the publishing countries, institutions, disciplines, and scholars to understand the basic status of sweetpotato research; then, visual analysis was conducted on high-frequency keywords, burst keywords, and keyword clustering; the evolution of major research hotspots and the development trend in different periods were summarized. Finally, the three main development stages--preliminary stage (1993-2005), rapid stage (2006-2013), and diversified mature stage (2014-2022)--were reviewed and analyzed in detail. Particularly, the development needs of sweetpotato production in improving breeding efficiency, enhancing stress tolerance, coordinating high yield with high quality and high resistance, and promoting demand were discussed, which will help to comprehensively understand the development dynamics of sweetpotato research fromdifferent aspects of biological exploration. [ABSTRACT FROM AUTHOR]

In this research, the star gold structure with beta graphene is thoroughly examined. We mainly focus on computing degree-based topological indices, which provide information about the network's connectivity and complexity as well as structural features. In addition, we compute an entropy measure to represent the uncertainty, information richness, and degree of unpredictability in the network. Furthermore, this study explores the relationships between topological descriptors and entropy using regression models that are logarithmic, linear, and quadratic. By merging these regression models, we uncover hidden patterns and understand the underlying ideas governing the network's behaviour. Our findings shed light on the connection between topological indices and entropy. This work improves our understanding of star gold structure dynamics and provides a visual framework for interpreting their behaviour. [ABSTRACT FROM AUTHOR]

In dryers where mechanical mixing is applied, it is necessary to know the motor power requirement in order to design the dryer correctly. The power requirement of the motor can be traced back to the no-load power requirement and the mixing power requirement. In this study, a new dimensionless power number equation has been introduced to determine the mixing power requirement of horizontal agitated drums. A simplified form of the dimensionless power equation for the investigated agitated drum and granular material was created. The equation took into account the effect of the mixing Froude number. The values of the equation's unknown parameters were determined by a nonlinear solver using laboratory measurements. A new dimensionless number was introduced which contains the mixing power requirement and was named cohesive power number. This dimensionless number determines the relationship between the mixing power requirement and the bulk cohesion by taking into account the typical size of the mixer and the rotational speed. [ABSTRACT FROM AUTHOR]

To investigate the hydraulic effects and performance of the micro-pressure filtration and cleaning tank under conditions with sandy and brackish water, physical model tests were conducted with five groups of flow rates (6–14 m³ h−1), four groups of sediment contents (0.5–2.0 g l−1), five groups of mineralisation degrees (0–5.0 g l−1), and three groups of screen apertures (0.125, 0.150, and 0.180 mm). Dimensional analysis, multiple linear regression analysis, and the non-dominated sorting genetic algorithm II (NSGA-II) were used to analyse the test results. The results showed that the optimal operating conditions of the micro-pressure filtration and cleaning tank under the scope of this test were a screen aperture of 0.175 mm, a flow rate of 13 m3 h−1, a sediment content of 1.8 g l−1, and a mineralisation degree of 4.7 g l−1. The micro-pressure filtration and cleaning tank was intermittently discharged and rinsed, the discharge time was 30–40 s, and the flow rate of discharge and rinsing was 5.54 m3 h−1. Prediction models of the head loss and the filtration efficiency of the filter were established. The coefficients of determination (R2) were greater than 0.9, the average relative errors of the predicted and measured values were 2.98% and 2.17%, respectively, and the corresponding root mean square errors were 0.0549 m and 0.642. The research results can be used as a reference for in-depth investigations on the performance of the micro-pressure filtration equipment in front of pumps. • Head loss and filtration efficiency models of pre-pump filters were established. • Optimal working condition of the filter was obtained using NSGA-II. • Optimal discharge time and discharge flow rate were determined. [ABSTRACT FROM AUTHOR]

We give an asymptotic evaluation for the number of automorphic characters of an algebraic torus T with bounded analytic conductor. The analytic conductor is defined via the local Langlands correspondence for tori by choosing a finite-dimensional complex algebraic representation of the L-group of T . Our results therefore fit into a general framework of counting automorphic representations on reductive groups by analytic conductor. [ABSTRACT FROM AUTHOR]

This article introduces the notion of global quadratic variation which is based on a notion weaker than the usual tensor topology appearing in the literature of stochastic processes in Banach separable spaces. It is based on convergence in the weak-star topology of approximating sequences. This calculus pursues in the infinite dimensional space the stochastic calculus via regularization introduced by Russo and Vallois for real valued processes and developed in Banach space by Di Girolami and Russo. This article in particular focuses on the relation with classical calculus in order to compare our global quadratic variation with the classical existing notions of quadratic variations in the literature. [ABSTRACT FROM AUTHOR]

Threshing capacity and fuel consumption in postharvest operations are the main factors in selecting a thresher. The problem was user was not easily understood the relation thresher capacity and fuel consumption. To easily understand the relationship, a model is needed for the independent and dependent factors. The model was developed for threshing capacity, and fuel consumption depends on parameter factors. The purpose of modeling is to select threshers, estimate thresher capacity, and identify direct and indirect factors. There are nine independent variables. These are: cylinder diameter (d), cylinder length (L), concave clearance (Cc), feed rate (Fr), drum speed (S), moisture content (Mc), crop straw ratio (R), spike/peg length (PL), and crop bulk density (ρ) and The Buckingham, pi theorem is used in basic dimensional. The threshing capacity and fuel consumption were developed. The equation was TC is equal to d²vρ (L*d-1, L*d-1, Fr *d-2Vρ) MC* SR and for fuel consumption of stationary thresher was Fc is equal to d²v (L*d-1, L*d-1, Fr*d-²Vρ) MC* SR developed. The performance investigation was conducted at three levels of drum speed (1000, 1100, and 1200 rpm) and feed rate (600, 700, and 800 kg h-1) with split-plot experimental design. The maximum threshing capacity is 234.22 kg h-1 at feed rate 800 kg h-1 and a drum speed of 1200 rpm and it consume 2.245 L h-1. The lowest threshing capacity is 223.20 kg h-1 at drum speed is 1000 rpm and the feed rate is 600 kg h-1 with fuel consumption is 2.00 L h-1. The equation developed contributed to research in that it helped researchers and designers easily understand the relation of thresher performance determinants. Consequently, using a model created by dimensional analysis is the most effective method for comprehending thresher-related parameters as result, as the speed of the drum increases, the thresher capacity increases as fuel consumption increases. Therefore, the developed model is a simple and easy way to choose and design the thresher. [ABSTRACT FROM AUTHOR]

Hydraulic structures at river crossings, especially culverts in ephemeral streams, are susceptible to damage during floods due to culvert scour, caused by various factors. It is essential to implement preventive measures to ensure the longevity and safety of these structures. This paper aims to present a comprehensive review of the factors influencing local scour downstream of culverts, offering a thorough understanding of this phenomenon. Consequently, a thorough review of the experimental studies and their corresponding outcomes documented in the literature is conducted. The analysis is divided into two main sections. The first section discusses dimensional analysis, while the second section delves into the key parametric factors affecting scouring, including flow regime, scour time, and experimental studies documented in the literature. The methods used in the second section are categorized into three distinct categories: channel and culvert dimensions, flow conditions, and sediment characteristics. This article not only provides a platform for researchers to conduct laboratory research but also assists hydraulic engineers in identifying crucial factors in culvert design. [ABSTRACT FROM AUTHOR]

There is an increasing expectation to demonstrate research equity awareness which charges researchers with the responsibility to methodologically attend to issues of ethical and equitable inclusion in qualitative research. While many strategies toward this end have made strides in improving research inclusion in terms of enhancing inclusive participation in research, little evidence is available to guide researchers in promoting inclusive representation in research. We examine the conceptual and practical relevance of transcription for addressing inclusive representation in qualitative research through the introduction of "transcript alignment" as an alternative to transcript cleaning, transcript checking and reviewing transcripts for verbatim accuracy. Practically, transcript alignment addresses seven common pitfalls of axio-analytic neutrality that impact inclusive representation: missing data, mistaking data, tidying data, overlooking data, shrinking data, sanitizing data, and removing data. Integrating transcript alignment into their practice, qualitative researchers can reaffirm the naturalistic tenet of "investigator as instrument," generate "thick transcription," and ultimately carry forward an ethos of participant inclusion throughout data analysis and presentation activities. Continued assessment and refinement of the practical application of the concept of transcript alignment has potential to enhance ethical and inclusive research conduct across all phases of the research process. [ABSTRACT FROM AUTHOR]

This paper presents a thorough manufacturability study of 2507 super duplex stainless steel (SDSS) produced by the Laser Powder-Directed Energy Deposition (LP-DED) process. First, experimental observations on single-track surface morphology and geometrical characteristics are described. Then, dimensional and porosity analyses of thin walls and bulk samples are presented and discussed in order to identify the optimal process parameter combinations, from a process point of view, for further characterizations to determine the general properties of LP-DED-printed samples. Finally, the results obtained on wrought steel of the same grade are compared to those of the printed material in terms of microstructure, texture, and ferrite/austenite ratio. A set of meticulously chosen process parameters with regard to the process and the machine (nozzle size, maximum power deliverable) gives the optimal results for the as-built LP-DED material in terms of porosity and microstructure quality but with smaller grains (irrespective of the phase studied) and a higher proportion of ferrite (about 75%). [ABSTRACT FROM AUTHOR]

[Display omitted] • Generation mechanisms of eddy current force and torque have been identified; • Conversion relation between force and torque provides a new optimization path; • Effects of magnetic field parameters on electrodynamic processes are clarified; • Mechanical models applicable to different scales can be used to expand new fields. Enhancing the recovery efficiency of non-ferrous metals in eddy current separation is of great significance. In this study, the accuracy of the simulation model was verified by comparing the eddy current force. The transformation mechanism of the Lorentz forces into the eddy current force and torque in non-ferrous metal particles was revealed by analyzing various physical fields. Then, the influence of magnetic field parameters on eddy current, eddy current force, and torque was studied. It shows that the eddy current force and torque are affected by the vector gradient of the magnetic field and the magnetic flux density, respectively. Additionally, the time derivative of the magnetic field impacts the magnitude of the eddy current force and torque by controlling the eddy current. On this basis, the empirical models of eddy current force and torque were established by similarity theory. The results obtained can improve and expand the application of eddy current separation. [ABSTRACT FROM AUTHOR]

This study establishes a three-dimensional cohesive model of multi-cluster hydraulic fracturing using finite element method (FEM). It fully considers the interaction between the interlayer and the reservoir and analyzes the key factors influencing fracture propagation. The results show that during the initial stage of hydraulic fracturing, the width of the edge fracture is greater than that of the mid fracture, while the situation is reversed for the fracture length. A larger cluster spacing leads to less interaction between fractures, while a greater number of clusters increases the interaction between fractures. With an increase in displacement, the lost fracturing fluid entering the formation enhances the interaction between fractures. An increase in elastic modulus results in a decrease in the width and height of edge fractures but an increase in their length, with little impact on mid fractures. As Poisson's ratio increases, there is little change in the fracture morphology of edge fractures, while the width and height of mid fractures increase significantly. With an increase in permeability, the influx of fracturing fluid into the interlayer decreases, leading to a reduction in the interaction between fractures. Finally, the study analyzes and discusses the impact of these parameters on the SRV (stimulated reservoir volume) in both the reservoir and the interlayer. These findings provide new insights for hydraulic fracturing and contribute to improving its productivity. [ABSTRACT FROM AUTHOR]

We derive an equation that applies for the wing-beat frequency of flying animals and to the fin-stroke frequency of diving animals like penguins and whales. The equation states that the wing/fin-beat frequency is proportional to the square root of the animal's mass divided by the wing area. Data for birds, insects, bats, and even a robotic bird—supplemented by data for whales and penguins that must swim to stay submerged—show that the constant of proportionality is to a good approximation the same across all species; thus the equation is universal. The wing/fin-beat frequency equation is derived by dimensional analysis, which is a standard method of reasoning in physics. We finally demonstrate that a mathematically even simpler expression without the animal mass does not apply. [ABSTRACT FROM AUTHOR]

Timely and accurate misalignment fault detection in rotor bearing systems is crucial for reliable and efficient operation, especially in Industry 4.0 based condition monitoring. The method described in this paper uses artificial neural networks (ANN) and empirical modelling to identify misalignment defects in rotor bearing systems. To capture the dynamic behaviour of the rotor bearing system under different operating conditions and fault scenarios, an empirical model based on Dimensional Analysis (DA) is developed. This model is trained using vibration data obtained from a well-aligned system. By comparing the predicted response with the actual vibration response, an accuracy of 8% to 10% is achieved. However, accurately quantifying the severity of misalignment poses challenges due to system nonlinearities. To address this issue, an ANN is employed to learn the mapping between vibration features and misalignment levels. To train the ANN, a comprehensive dataset is created through experiments conducted on a test rig. Artificial misalignment is introduced to the rotor, and vibration signals are analysed under various conditions of misalignment, rotor speed, and static load. The trained ANN is validated using experimental data, demonstrating an impressive accuracy of 99.46%. This integrated approach holds significant potential for predictive maintenance, leading to improved operational efficiency. [ABSTRACT FROM AUTHOR]

The aim of this work was to evaluate the antineoplastic effect of newly synthesized nanoparticles based on poly(lactic-co-glycolic acid) (PLGA) alone or PLGA esterified with 2,2′-[propane-2,2-diylbis (thio)] diacetic acid (TKL), loaded with docetaxel (DTX) and/or docosahexaenoic acid (DHA), as innovative site-specific therapeutic carriers. The obtained materials were characterized by FT-IR and 1H-NMR, while the dimensional analysis of the nanoparticles obtained was performed by Dynamic Light Scattering. The encapsulation efficiency of the nanoparticles was evaluated, and in vitro skin permeation tests were also performed. The antitumor activity of the nanomaterial was studied in the human adenocarcinoma HCT116 cell line. In particular, viability tests in bidimensional culture, as well as in tumor spheroids, were conducted. The use of these nanocarriers could facilitate the stable and efficient delivery of DTX and DHA through the upper segments of the gastrointestinal tract to the colon. In addition, the presence of the ROS-sensitive 2,2′-[propane-2,2-diylbis (thio)] diacetic acid in their matrix should promote the site-specific release of DTX in the tumor mass, where high levels of reactive oxygen species could be found. [ABSTRACT FROM AUTHOR]

Pounding between adjacent structures subjected to earthquake actions can cause significant damage. Due to the many uncertainties inherent to the seismic input and the impact phenomenon, a probabilistic assessment of the occurrence of seismic pounding and of its consequences on the structural performance is necessary. This work analyzes the problem of pounding by considering a single-degree-of-freedom benchmark system surrounded by rigid boundaries and subjected to a stochastic earthquake input. Although simplified, the model is representative of several realistic configurations, such as base-isolated systems surrounded by moat walls or bridge decks near the bridge abutments. The problem is cast in non-dimensional form and a parametric study is carried out to evaluate the influence of the identified non-dimensional input parameters on the statistics of the response. A probabilistic demand model is developed for the impact forces via non-linear regression, with the demand expressed as a function of the identified non-dimensional parameters. This model provides an estimate of median pounding force and of its dispersion given the seismic intensity of the input. Finally, global sensitivity analysis is used to rank the model parameters in terms of their influence on the system performance. [ABSTRACT FROM AUTHOR]

A simplified mathematical model of two-phase multicomponent flow in the reservoir— multistage hydraulic fractures—horizontal well system is proposed. The formulation of transport problems in the well and in hydraulic fractures is simplified based on the dimensional analysis and similarity theory. The possibility of transition to a quasi-steady-state problem of distribution of the mixture components in high-permeability hydraulic fractures is shown. The dimension of the problem in reservoir is reduced by decomposing the problem into a set of problems in independent fixed stream tubes. For numerical solution of the problem, the resulting reduction in computer time reaches two orders of magnitude and can be further reduced by using parallel computing. Accelerating the solution of the direct problem is fundamentally necessary for the possibility of solving the inverse problem of identifying the porosity and permeability properties of fractures from the results of interpretation of tracer studies. [ABSTRACT FROM AUTHOR]

Condensation on surfaces in the presence of non-condensable gas (NCG) is a ubiquitous and critical phenomenon in many industrial fields. However, current empirical correlations for predicting condensation heat transfer coefficients in the presence of NCG may exhibit significant deviations from reality. Machine learning algorithms are now being dedicated to this field, but the models developed can only predict the condensation heat transfer coefficients of steam or vapor of a non-aqueous working fluid with similar physical properties to water in the presence of NCG. In the present study, a comprehensive theoretical analysis was conducted to investigate the total condensation heat transfer coefficients with NCG, and 16 dimensionless numbers were identified as input variables for machine learning models. Based on a filtered database consisting of 4377 data points extracted from 37 papers, the Spearman correlation coefficients were calculated to evaluate the relationship between the total heat transfer coefficients and the input variables, indicating the magnitude of the impact of the 16 dimensionless variables. Four machine learning models, namely Gradient Boosting Regression (GBR), Extreme Gradient Boosting (XGBoost), Random Forest Regression (RFR), and Multilayer Perceptron (MLP), were developed to predict the total heat transfer coefficients for water and non-aqueous working fluids. The mean absolute percentage errors for the four models were 1.38%, 1.63%, 3.00%, and 4.42%, respectively, with the GBR model exhibiting the highest degree of accuracy. The determination of the application scope of these models was conducted by analyzing the value ranges for each dimensionless parameter and its corresponding frequency distribution. • Four machine-learning models were developed to predict condensation heat transfer. • Sixteen dimensionless variables were determined as input parameters for these models. • These models can predict condensation heat transfer under different working conditions. • Conditions were diverse in types of wall geometry, convection, working fluid and NCG. [ABSTRACT FROM AUTHOR]