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Highlights PEEK and CF/PEEK are two significant materials whose properties are intricately linked to their crystallization behavior. This study employed three analytical techniques—density method, differential scanning calorimetry (DSC), and x‐ray diffraction (XRD)—to explore and quantify the crystallinity of Poly (ether ether ketone) (PEEK) and its composites. Thermogravimetric analysis was used to determine the resin content of the composites, which is essential for the density and DSC methods. The density method, based on Archimedes' principle, calculated both mass and volume crystallinity. DSC assessed crystallinity by analyzing differences in melting enthalpy, while XRD determined crystallinity through diffraction patterns and peak analysis. The results demonstrate that these three techniques can be effectively utilized for calculating the crystallinity of PEEK and its composites. Using the density method, PEEK exhibited a crystallinity of (26.53 ± 1.30)% by mass and (24.57 ± 1.24)% by volume. The prepreg, CF/PEEK, and CF/PEEK‐AA1 composites showed enhanced crystallinity values. Crystallinity calculated by DSC was 29.16% for PEEK, 55.35% for prepreg, 55.48% for CF/PEEK, and 53.50% for CF/PEEK‐AA1. XRD results provided crystallinity values of 46.35% for PEEK, 63.20% for prepreg, 64.80% for CF/PEEK, and 66.57% for CF/PEEK‐AA1, along with detailed information about unit cells and crystal planes. This study contributes to a better understanding of these methods, paving the way for future refinement and integration, thereby improving the precision of crystallinity determination.Crystallinity study of PEEK and CF/PEEK composites by density, DSC and XRD methods. Crystallinity calculated by methods in different principles are irrelevant. Crystallinity estimated by density and DSC requires resin content. Information on crystal and crystallinity can be obtained by XRD independently. Crystallinity calculated by XRD is the highest. Results obtained by density and DSC method are close. [ABSTRACT FROM AUTHOR]

Extension of the feeders and high power demand have resulted in more substantial power dissipation and reduced voltage decline. Therefore, minimizing power loss and enhancing the voltage profile are imperative for efficient energy distribution. This research introduces a novel approach called the Hybrid Archimedes Optimization Algorithm (HAOA), which combines the Levy flight and Archimedes Optimization Algorithm (AOA) to improve the performance of AOA. AOA replicated the upward impulse described by Archimedes principle in physics and experienced an imbalance between exploitation and exploration. Utilizing Levy flight results in an improved balance between exploration and exploitation, enhancing algorithm performance in finding optimal solutions. Therefore, hybridizing Levy flight with AOA to enhance its performance results in an improved trajectory balance between exploration and exploitation. This trajectory is utilized to update the object's position in AOA and is regarded as a feasible method to enhance the slow performance of AOA. The HAOA algorithm was employed to optimize network reconfiguration to decrease power loss and voltage deviation (VD) and improve the voltage stability index (VSI) in radial distribution networks (RDN). The validation of HAOA was assessed using the IEEE 33 and 69 bus systems. The power loss for the IEEE 33 and 69 test systems dropped to 139.55 and 98.459 kW, respectively, compared to the base case values of 202.677 and 224.96 kW. The VD for the 33 and 69 bus systems is 0.00134 and 0.000306 p.u, respectively, compared to the base case values of 0.0035498 and 0.001443 p.u. The VSI has been enhanced to 0.785 p.u for the 33 bus system and 0.8126 p.u for the 69 bus system following the reconfiguration. The results indicate that HAOA outperforms other approaches in terms of lower power, VD, and voltage stability enhancement. [ABSTRACT FROM AUTHOR]

This study addresses a research gap in composite material development by exploring the potential of innovative waste materials to enhance performance. An innovative and cost‐effective waste material serves as a reinforcing agent, with cenosphere and molybdenum disulphide used in proportions ranging from 0% to 4%. Employing a cost‐effective stirring cast technique, composites are fabricated, combining AA7075 alloy with cenosphere particles (AA7075/cenosphere) and molybdenum disulphide particles (AA7075/MoS2). The experimental design, utilizing a central composite design within the response surface methodology framework, examines the weight percentages of cenosphere and MoS2. Scanning electron microscopy reveals strengthening chemicals within the matrix, confirmed by electronic dispersive X‐ray spectroscopy for individual reinforcements in the aluminium alloy matrix. Density determination follows Archimedes' principle and the OIML G14 standard, while mechanical properties (hardness and ultimate tensile strength) are assessed per ASTM standards. Results demonstrate a significant reduction in composite density with cenosphere reinforcement, while molybdenum disulphide marginally affects density. The incorporation of reinforcements notably enhances both hardness and ultimate tensile strength. In conclusion, this research bridges a composite material development gap, presenting a novel and sustainable approach. By showcasing the potential of unconventional waste materials, the study contributes valuable insights to material science and engineering, opening new avenues for future research. [ABSTRACT FROM AUTHOR]

Stereology is a discipline that allows us to obtain quantitative information about the geometric structure of three‐dimensional objects. In this study, the volume of grey matter (GM), white matter (WM), and lateral ventricle (LV) of the cerebral hemispheres (CH) in sheep and goats were calculated. For this purpose, six healthy male sheep and goat brains (1–2 years old) without any anomaly were used. Brains were fixed with 10% formaldehyde in the skull. The skull was opened using standard anatomical dissection methods, and the brains were carefully removed. Brain weight and volume were measured (using Archimedes' principle) after the meninges were removed. The cerebral hemispheres were separated from the other parts of the brain by a section made in front of the rostral colliculus. In the same way, the weight and volume of the cerebral hemispheres were measured. Afterward, the cerebral hemispheres were blocked with agar, and transversal cross sections (from rostral to caudal) with an average thickness of 3.42 mm were taken from the cerebral hemispheres. Grey matter was stained with Berlin blue macroscopic staining method. The stained cross sections were scanned at 600 dpi resolution, and a point counting grid was placed on the images with the ImageJ software. Cavalieri's principle calculated the surface area and volume measurements of the grey matter, white matter, and lateral ventricle. GM, WM, and LV volumes in sheep and goat cerebral hemispheres were calculated as 54.94, 21.48 and 3.06 mL in sheep, 57.46, 24.13 and 3.12 mL in goats, respectively. The percentages of these structures in the total hemisphere volume were 71.83%, 28.17% and 4.00% in sheep, 70.42%, 29.58% and 3.82% in goats, respectively. Asymmetry was not observed in cerebral hemispheres in both species. A difference was found in the WM, LV and LV: CH ratios in the right/left comparison of the goat (p < 0.05). In comparing sheep and goats, a significant difference was observed in WM right, WM left, WM total, CH left and CH total (p < 0.05). In conclusion, the cerebral hemispheres' grey matter and white matter ratio are frequently used to diagnose neurodegenerative diseases. In recent years, the increase in neurodegenerative disease models in farm animals has been enormous. It is thought that these values obtained from healthy animals in the current study will be important for such experimental studies in the future. [ABSTRACT FROM AUTHOR]

Titanium and its alloys are used to make dental implants because of its low density, high strength, and corrosion resistance. This paper describes the development of a potential biomaterial Ti‐10Nb by powder metallurgy utilizing four different compaction pressures and analyses its microstructural, physical, mechanical, electrochemical, biological, and tribological behavior under various situations. The alloys were fabricated using four different compaction pressures, that is, 600, 650, 700, and 750 MPa, and sintered in a vacuum atmosphere at 1000°C for 1.5 h. The density of the samples was measured using Archimedes principle. X‐ray diffraction and scanning electron microscopy equipped with energy dispersive spectroscopy were used to investigate the phase composition and microstructure, and a profilometer was used to examine the surface roughness of various samples. Vickers hardness tester was used to evaluate hardness, and a universal testing machine was used for compression testing. Corrosion and wear behavior were examined using a potentiostat and a Bio‐Tribometer, respectively. This Ti‐10Nb alloys consist of α + β phase, and have 16% highest porosity in sample compacted at 600 MPa. The samples compacted at 750 MPa achieved highest hardness, yield strength, compressive strength, and elastic modulus of 450 ± 29.72 HV, 718.22 ± 16.37 MPa, 1543.59 ± 24.37 MPa, and 41.27 ± 3.29 GPa, respectively. In addition, it also possesses highest corrosion and wear resistance with lowest icorr of 0.3954 ± 0.008 μA/cm2 and wear volume of (31.25 ± 0.206) × 10−3 mm3. These results indicate that the developed alloys have a variety of desirable properties, including high hardness, adequate compressive strength, good corrosion and wear resistance, apatite‐forming capability, and a low elastic modulus, which is advantageous for avoiding stress shielding. Therefore, it may be recommended to use it as a dental implant material. [ABSTRACT FROM AUTHOR]

This study investigated the morphological features of the ventricular system of the brain in Akkaraman sheep in a measured and structural manner. In the study, 24 adults male Akkaraman sheep, which is a common and hornless breed were used. Anatomical features of the ventricular system were determined by latex injection and dissection, acrylic injection and corrosion cast and magnetic resonance imaging. In the measurements, a precise digital calliper, Archimedes' principle, Cavalieri's principle and ITK‐SNAP imaging were used by comparing them with each other. The average weight of fresh sheep brains was 102 g (0.226 lb), the volume 115.8 mL and the length, height and width were 130.78, 40.58 and 70.08 mm, respectively. The olfactoric bulb contained a cavity associated with the lateral ventricle, large enough to be called a ventricle. The cavity of septum pellucidum has a large cavity was observed. However, there was no cerebrospinal fluid in this cavity. The interventricular foramen of the dissected brain was also an opening measuring 1.4 mm × 3.9 mm × 5.5 mm. The total volume of the ventricles of the brain of Akkaraman sheep was found to be 7107.71 ± 479, 7115 ± 737 and 7080 ± 647 mm3 and 6200 mm3 using the Planimetry, Point Counting method, ITK‐SNAP program, and Archimedes' principle, respectively. In the study, species and breed‐specific brain indices values and many detailed morphometric data were obtained. [ABSTRACT FROM AUTHOR]

A series of quaternary tellurite‐based glasses (72−x)TeO2 + 25B2O3 + 3K2CO3 + xDy2O3, where (x = 0, 0.5, 1, 1.5, 2, 2.5), are prepared using melt quenching technique. The effect of dopants on structural, physical, optical, and thermal properties of alkali boro‐tellurite glasses are studied using the differential thermal analysis (DTA) technique, UV–vis spectrometer, and photoluminescence technique. The density of as‐prepared samples has been obtained using the conventional Archimedes principle and other physical parameters, viz. molar volume and ion concentration, are also calculated using density. The optical absorption spectra exhibits different excited states of Dy3+ corresponding to 6H15/2→ 6F5/2(∼805 nm), 6F3/2(∼755 nm), 4F9/2 (∼473 nm), 4I15/2 (∼454 nm), 4G11/2 (∼427 nm), 4F7/2(389 nm), 4P3/2(∼366 nm). With the increase in Dy+3 concentration, an increase in optical bandgap, density, and molar volume as well as decrease in molar reflectivity, and reflection loss is evident from this study. The effect of Dy+3 ion concentration on Y/B intensity ratios and CIE chromaticity coordinates have been evaluated to understand the possible applications of aforementioned glass samples for white‐light‐emitting diodes (WLEDs). Moreover, various shielding parameters, viz. half value layer (HVL), mean free path (MFP), effective atomic number (Zeff), mass attenuation coefficient (MAC) have also been determined to understand the shielding characteristics of as‐prepared glass samples. [ABSTRACT FROM AUTHOR]

The carbochlorination in molten salt is an effective method for titanium extraction form low‐grade titanium slag with a high calcium and magnesium content. However, in industrial practice, the fluidity of molten salt will gradually decrease with the increase of CaCl2 content. It is important to elucidate the influencing mechanism of CaCl2 content on the microstructure and diffusion properties of molten salt for the rational selection of a molten salt system and clean utilization of titanium slag. In this study, the densities of molten salt systems with different CaCl2 contents are measured according to the Archimedes principle. Then, using the first‐principles molecular dynamics (FPMD) method, the ionic structure and transport properties of NaCl‐MgCl2‐CaCl2 ternary molten salt systems under different CaCl2 contents are qualitatively and quantitatively described by determining the partial radial distribution functions (PRDF), coordination number (CN), angular distribution functions (ADF), and diffusion coefficient (DC). The results show that with the addition of CaCl2, Ca2+ ion complexed with Cl− ion to form larger ionic clusters, which reduced the proportion of free Cl− ion and restricted the diffusion of Cl− ion. [ABSTRACT FROM AUTHOR]

Formation is considered a cost and time intensive production step in industrial production of lithium‐ion batteries (LIBs). One solution for improvement is an acceleration of the formation step by applying higher C‐rates. In this study, formation protocols with up to 2 C were applied to LiNi0.6Mn0.2Co0.2O2 (NMC622) II graphite pouch cells with a nominal capacity of 5 Ah. The formation protocols utilizing higher C‐rates result in a decrease in overall formation time, but also in increased gassing due to additional electrolyte decomposition. The resulting gas phase was quantitatively determined using gas chromatography‐barrier discharge ionization detection (GC‐BID) and with regard to gas volume by making use of the Archimedes principle. Main formation gases in these cells were identified as CO and C2H4. Increased C‐rates altered certain decomposition reactions. Especially the CO evolution was increased. Nevertheless, gassing was smallest for 0.1 C and increased with lower and higher C‐rate. In case of too low C‐rates hydrogen was identified as the main formation gas. However, higher gassing was not correlated with higher capacity loss during formation. Furthermore, the dependence of the C‐rate on gassing was found to be dependent on the graphite material. [ABSTRACT FROM AUTHOR]

In this paper, the physicochemical and mechanical properties of Raffia vinifera pith (RVP) are discussed. Microscopic observations have shown that the structure of the RVP is similar to that of a composite consisting of natural fibers. The effective area ratio of Raffia vinifera (RV) fibers was evaluated along the raffia stem using ImageJ software, and it decreases from the periphery to the center. Energy dispersion spectrometer (EDS) analysis shows that RVP is essentially composed of carbon and oxygen. Densities of RVP and its matrix were determined using Archimedes' principle and law of mixtures, respectively; from the results obtained, they can be considered as one of the lightest materials. Young's modulus of RVP has been obtained from tensile and bending tests, while that of matrix has been obtained using the law of mixtures during tensile tests. RVP has better specific properties, and the results of the matrix properties show that we can easily select another matrix which has better properties than the case studied during the elaboration of composites. [ABSTRACT FROM AUTHOR]

Following Archimedes' Principle, any object immersed in a fluid is subject to an upward buoyancy force equal to the weight of the fluid displaced by the object. This simple description is the origin of a set of effects that are ubiquitous in nature, and are becoming commonplace in games, simulators and interactive animations. Although there are solutions to the fluid‐to‐solid coupling problem in some particular cases, to the best of our knowledge, comprehensive and accurate computational buoyancy models adequate in general contexts are still lacking. We propose a real‐time Graphics Processing Unit (GPU) based algorithm for realistic computation of the fluid‐to‐solid coupling problem, which is adequate for a wide generality of cases (solid or hollow objects, with permeable or leak‐proof surfaces, and with variable masses). The method incorporates the behaviour of the fluid into which the object is immersed, and decouples the computation of the physical parameters involved in the buoyancy force of the empty object from the mass of contained liquid. The dynamics of this mass of liquid are also computed, in a way such that the relation between the centre of mass of the object and the buoyancy force may vary, leading to complex, realistic beha viours such as the ones arising for instance with a sinking boat. [ABSTRACT FROM AUTHOR]

Airy isostasy is commonly used in planetary science to explain the relationship between crustal thickness variations and topography. Recently, several researchers have questioned the validity of this concept and proposed alternative approaches. Here we examine the accuracy of these approaches by comparing their results with those obtained from the numerical solution of the equations governing the flow in the crust of a small icy moon with a subsurface ocean. We find that the traditional approach based on application of Archimedes' principle with elevations referred to the geoid, provides a satisfactory estimate of crustal thickness for low harmonic degrees. The alternative approach, based on the deviatoric stress minimization, gives correct results for isoviscous model, but its accuracy deteriorates as the viscosity contrast increases. The other alternative approach, in which the deviatoric stress is neglected, is significantly less accurate than other methods, leading to biased results for models with a thick crust. Plain Language Summary: Airy isostasy is a concept based on simple application of Archimedes' principle, which is broadly used in solid Earth geophysics and planetary science to explain the relationship between crustal thickness variations and topography. However, the application of Airy isostasy to icy bodies is problematic due to large variations in ice viscosity and phase transitions occurring in the interior. Recently, several researchers have questioned the validity of the traditional approach to Airy isostasy and proposed alternative approaches. Here we examine the accuracy of these approaches by comparing their results with those obtained from the numerical solution of the equations governing the flow in the crust of a small icy moon with a subsurface ocean. The results of our modeling suggest that the traditional approach to Airy isostasy provides a satisfactory estimate of crustal thickness variations on large spatial scales. The alternative approach based on the deviatoric stress minimization gives correct results for isoviscous model, but its accuracy deteriorates as the viscosity contrast increases. The other alternative approach, in which the deviatoric stress is neglected, is significantly less accurate than the other methods, leading to biased results for models with a thick crust. Key Points: Application of Airy isostasy to icy moons with a subsurface ocean is problematic due to phase transitions and large viscosity variationsThe traditional equal weight approach to Airy isostasy, as well as the deviatoric stress minimization, leads to acceptable resultsThe recently proposed equal pressure approach is less accurate than other approaches leading to biased results for moons with a thick crust [ABSTRACT FROM AUTHOR]

The addition of bioactive glasses to a Y:TZP matrix represents a feasible alternative to provide bioactivity to this material and optimize osseointegration. This work evaluated the effect of the BG concentration (0 and 10 wt%) and the sintering temperature (1200°C and 1300°C) on the microstructure, relative density, and flexural strength of the composite Y:TZP/BG. The Y:TZP and Y:TZP/BG powders were uniaxially pressed and sintered at 1200°C or 1300°C for 1 h. The microstructure was characterized by X‐ray diffraction analysis, scanning electron microscopy, and energy‐dispersive X‐ray Spectroscopy. Relative density was calculated from density values obtained using the Archimedes' principle. For the flexural strength, specimens (n = 6) were fractured in a biaxial flexural setup using a piston‐on‐three‐balls fixture in a universal testing machine. Bioactivity test was performed in simulated body fluid solution. The results suggested that BG addition decreased the grain size of the composite, increased porosity and caused a significant decrease in the relative density and flexural strength. Crystalline phases of calcium stabilized cubic zirconia and sodium zirconium silicate were formed after the addition of BG. Finally, it was concluded that composite specimens sintered at 1300°C showed the highest density values and larger grains compared to those sintered at 1200°C. [ABSTRACT FROM AUTHOR]

Robust Realists think that there are irreducible, non-natural, and mind-independent moral properties. Quasi-Realists and Relaxed Realists think the same, but interpret these commitments differently. Robust Realists interpret them as metaphysical commitments, to be defended by metaphysical argument. Quasi-Realists and Relaxed Realists say that they can only be interpreted as moral commitments. These theories thus pose a serious threat to Robust Realism, for they apparently undermine the very possibility of articulating the robust metaphysical commitments of this theory. I clarify and respond to this threat, showing that there is in fact space to develop and defend a robust moral ontology. [ABSTRACT FROM AUTHOR]

The densities of quaternary glass-forming systems within the CaO-MgO-Al2O3-SiO2-composition ( CMAS) were evaluated. Their compositions differed not more than 5 mol% for each component from each other. After melting, the exact chemical compositions were measured using X-ray fluorescence and the densities were determined by Archimedes method and pycnometry. This property and its dependency upon small variations in the composition is the main focus of this paper. The density values were between 2.617 and 2.700 g/cm³ and the packing density factors Vp of the oxide glasses using the ionic radii of Pauling ranged from 0.562 to 0.574. The experimentally determined data were compared to different model calculations. Calculations performed according to empirical formulae given in the literature showed relative deviations between −5 and 12% to the experimental values. The effect of MgO was also studied by comparing the glasses with similar compositions (Ceram Int, 2016;42:5810-5822 ) without any MgO. [ABSTRACT FROM AUTHOR]

Advances in sensors for biomedical applications have been a great motivation. In this research, a PLZT (lead lanthanum zirconate titanate) novel sensor with platinum wire implanted in its longitudinal section was developed through of the synthesis process based on powder technology. The raw materials as lead (PbO), lanthanum (La2O3), zircon (ZrO2), and titanium (TiO2) were used in the formation of the chemical composition (62.8% PbO, 4.5% La2O3, 24.2% ZrO2, and 8.5% TiO2). Then, these powders were submitted to mix-mechanical milling at high energy; cylindrical samples with the implant of the platinum wire were obtained with the load application. Finally, the compacted samples were sintered at 1200°C for 2 hours, then followed by a polarization potential of 1500 V/mm at 60°C to obtain a novel sensor. The density and porosity were evaluated using the Archimedes’ principle, while the mechanical properties such as fracture toughness value and Young’s modulus were determined by indentation and ultrasonic methods, respectively. A microscopic examination was also carried out to investigate the structural properties of the material. The PLZT novel sensor is electronically arranged for monitoring the cardiac pulses through a data acquisition system. The results obtained in this research are analyzed and discussed. [ABSTRACT FROM AUTHOR]

The rotary chamber technique allows extended observation times of rising bubbles up into the 10-mm range. After establishing the technique in combination with optical sizing in previous publications, this work completes the case of nitrogen bubbles in tap water. The rise velocity and the mass transfer are measured for five degrees of water saturation. A one-parameter model equation involving the Archimedes number is offered for calculation. The limit of the analytical boundary layer model is depicted. [ABSTRACT FROM AUTHOR]

The paper presents the kinematics of mutual movement of an unmanned aerial vehicle (UAV) and a ground target. The controlled observation and tracking head (OTH) is a device responsible for observing the ground, searching for a ground target, and tracking it. The preprogrammedmovement of theUAV on the circle with the simultaneousmovement of the head axis on Archimedes' spiral during searching for a ground target, both fixed (bunkers, rocket missiles launching positions, etc.) and movable (tanks, infantry fighting vehicles, etc.), is considered. Dynamics of OTH during the performance of the above mentioned activities is examined. Some research results are presented in a graphical form. [ABSTRACT FROM AUTHOR]

The aims of this study were to determine the total volume of the horse kidney and volume fractions of its functional subcomponents (cortex, medulla, renal pelvis) using stereological methods and investigate any possible difference in the functional subcomponents of the right and left kidneys that may arise from differences in shape. The study was carried out on the kidneys of 5 horses of different breed and sex. The weight of the kidneys was measured by a digital scale, and kidney volume was calculated by Archimedes' principle. Total kidney volume and volume fractions of subcomponents of the right and left kidneys were estimated by the Cavalieri's principle. The weights of the right and left kidneys were 550 ± 25 g and 585 ± 23 g, respectively. The volumes of the right and left kidneys estimated using the Cavalieri method were 542 ± 46 ml and 581 ± 29 ml. The relative organ weight of the kidneys was calculated as 1:330. The densities of the right and left kidneys were determined to be 1.01 and 1.00, respectively. The mean volume fractions of the cortex, medulla and renal pelvis were determined as 55.6, 42.7 and 1.7 in both kidneys. No statistically significant difference existed between morphometric data pertaining to the right and left kidneys ( P > 0.05). To determine precisely whether differences in shape cause any difference in the functional subcomponents of the right and left kidneys requires further investigation of differences in the number of microscopically functional unit of the kidney such as renal glomeruli and nephrons. [ABSTRACT FROM AUTHOR]

The volume fractions of constituent phases are a rudimentary parameter for ceramic composites. Synchrotron-radiation computed tomography ( SR- CT) is an emerging three-dimensional characterization method, and this article is intended to explore its application in determination of the phase volume fraction for ceramic composite. The composite of yttria-stabilized zirconia ( YSZ) and Sr-doped LaFeO3 ( LSF) was used as a model material to examine the validity of the method. A three-dimensional image of the composite was obtained using the SR- CT method. The constituent phases of the composite were discriminated by the gray level of the pixels in the image, and their volume fractions were determined by counting the number of corresponding pixels. The volume fractions for YSZ and LSF were 56.8% and 36.6%, respectively, and the volume ratio of these two phases was 1.55, slightly higher than that calculated from the composition of the starting powders. The porosity of the composite determined by SR- CT was 6.6%, somewhat lower than that by the Archimedes method. For comparison, the phase volume fractions of the composite were also determined by analyzing its backscattered electron- SEM images, and the results of this two-dimensional method are in fair agreement with those of SR- CT. It is concluded that SR- CT with improved spatial and compositional resolution can give a fairly accurate measurement of the phase volume fraction of the ceramic composites. [ABSTRACT FROM AUTHOR]

In his last book, Toward a Logic of Meanings (), Jean Piaget describes how thought can be categorized into a form of propositional logic, a logic of meanings. The intent of this article is to offer this analysis by Piaget as a means to understand the language and teaching of science. Using binary propositions, conjunctions, and disjunctions, a table of binary operations is used to analyze the structure of statements about conclusions drawn from observations of science phenomena. Two examples from science content illustrate how the logic of binary propositions is used to symbolize typical reasoning of secondary-school science students. The content areas are the period of a pendulum and the Archimedes' Principle, which were chosen based on observations in secondary science classrooms. The analyses of the student responses in these two observations demonstrate the commonalities of arguments used by students of science as they try to make sense of observations. The analysis of students' reasoning, demonstrates that Piaget's logic of meanings is a useful and relevant tool for science educators' understanding of the syntactical aspects of pedagogical content knowledge. [ABSTRACT FROM AUTHOR]

The first part of this paper provides an overview of the state of the art of the hydrodynamics of liquid suspensions of solid particles. It is shown that knowledge of the suspension Archimedes number is sufficient to estimate the voidage–velocity parameters for suspensions of solids possessing homogenous characteristics, thereby completely defining the system from a fluid dynamic point of view. A general relation is presented which will indicate if a solid–fluid system will be in the fixed or in the suspended state depending on the relative velocity between the two phases. Modifications of the previous approach when the solid particles are not spherical have been also indicated. The basic features of the pseudo-fluid approach are then presented. This approach is useful when the solids making up the suspension have different sizes: by the introduction of the pseudo-fluid apparent characteristics (density and viscosity) it is possible to make basic estimations of the suspension behaviour. The second part of the paper outlines possible application of suspension theory to geological phenomena, such as the vertical transport of water–sand suspensions. Aspects of interest are the minimum pressure required for the transport of the suspension, the estimation of suspension flow rate through an overall pressure balance, the vertical transport of large ‘breccia’ blocks and the behaviour of the solid particles present in the rising conduit once the overpressure falls below the minimum value needed to sustain the flow. Finally, a warning is given on the limitations of the presented relationships (e.g. the assumption of homogeneous solid dispersion in the suspension) and on situations such as inclined conduits which require a different approach. [ABSTRACT FROM AUTHOR]

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The density of oxide glass including silicate, borate, phosphate, tellurite, and germanate glasses were measured using the Archimedes method. On the assumption that the ionic packing ratio is approximately a constant independent of chemical composition, an empirical equation for estimating the density from chemical composition was proposed. The calculated values are in reasonable agreement with the corresponding measured ones. [ABSTRACT FROM AUTHOR]

This work concerns nonstrict Archimedean triangular norms and cardinalities of fuzzy sets. Values of those t-norms are expressed in the language of Hamming distances between some fuzzy sets. We apply this optics to two important types of cardinalities, namely generalized FGCounts and generalized sigma counts. Finally, we prove that the well-known relationship between the FGCount and the sigma count of a fuzzy set is a limit property of generalized FGCounts involving Yager t-norms. © 2009 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Hydrodynamic parameters play a major role in the dynamics and control of Autonomous Underwater Vehicles (AUVs). The performance of an AUV is dependent on the parameter variations and a proper understanding of these parametric influences is essential for the design, modeling, and control of high-performance AUVs. In this paper, the sensitivity of hydrodynamic parameters on the control of a flatfish type AUV is analyzed using robust design techniques such as Taguchi's design method and statistical analysis tools such as Pareto-ANOVA. Since the pitch angle of an AUV is one of the crucial variables in the control applications, the sensitivity analysis of pitch angle variation is studied here. Eight prominent hydrodynamic coefficients are considered in the analysis. The results show that there are two critical hydrodynamic parameters, that is, hydrodynamic force and hydrodynamic pitching moment in the heave direction that influence the performance of a flatfish type AUV. A near-optimal combination of the parameters was identified and the simulation results have shown the effectiveness of the method in reducing the pitch error. These findings are significant for the design modifications as well as controller design of AUVs. [ABSTRACT FROM AUTHOR]

The article investigates anisotropic pore closure due to non-thermal microwave effects in ceramic sintering through microwave heating. The disadvantages of conventional ceramic sintering is discussed. The samples where characterized after sintering through the Archimedes Principle. Scanning electron microscopy revealed the correlation between pore orientation and linear polarized microwave fields.

This article studies the aggregation of transitive fuzzy relations. We first find operators that preserve transitivity and then extend the results to aggregating operators. As special cases, means and some kind of suitable ordered weighted averaging (OWAs) are used to aggregate transitive fuzzy relations with respect to an Archimedean t-norm. Three families of transitive relations that allow us to modify the entries of a given relation R continuously towards the smallest and the greatest ones in our universe are given. Aggregation of nonfinite families of transitive relations also is studied and applied to calculate the degree of inclusion or similarity of fuzzy quantities (fuzzy subsets of an interval of the real line). © 2003 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The article focuses on Archimedes' theories of floatation in the two-volume work "On Floating Bodies." His work presents no facts or experimental data. He begins with a single postulate about the nature of fluids that summarizes his knowledge about fluids. Archimedes' thinking on fluids represents a penetrating and abstract view of the interaction between the layers that leads to a state of "rest." The only concept Archimedes explicitly used in deriving his floatation law was that of weight. In his work, "Bodies That Stay Atop of Water in It," Galileo addresses the problems raised by Archimedes' model.

The ceramics, (0.65 + y) Pb( Zr0.47Ti0.53)-(0.35 − y) Pb[( Ni1− x Zn x)1/3 Nb2/3] O3 have a morphotropic phase boundary ( MPB) of pseudo-cubic and tetragonal structures. Their ε33 T/ε0 value considerably decreased on the pseudo-cubic side of the MPB composition, but the d33 and kp slowly decreased on both sides of the MPB. Therefore, the maximum transduction coefficient ( d33 * g33) was obtained from the composition on the pseudo-cubic side of the MPB, because g33 is given by d33/ε33 T. This result could be applied to other systems containing an MPB of pseudo-cubic and tetragonal structures. Furthermore, a d33 * g33 value of 20 056 × 10−15 m2/N, which is the highest value reported so far for polycrystalline ceramics, was obtained from the 0.68 Pb( Zr0.47 Ti0.53) O3-0.32 Pb( Ni0.6 Zn0.4)1/3 Nb2/3 O3 ceramic. [ABSTRACT FROM AUTHOR]

Single-phase polycrystalline microwave dielectric ceramics Ba6Ti1− xSn xNb4O18, with x changing from 0 to 1, were synthesized by the solid-state reaction method. All the solid solutions fitted well with A6B5O18 cation-deficient hexagonal perovskite structure. The substitution of Sn for Ti effectively enhanced the quality factor and controlled τf. With increasing Sn content, the dielectric constant decreased from ∼47 to ∼32, and the Q× f value increased significantly from 11 530 to 28 496 GHz, with τf varying from 64 to 0 ppm/°C. A zero τf was realized when Sn was fully replaced by Ti with the composition Ba6SnNb4O18. [ABSTRACT FROM AUTHOR]

Keywords: Anatomy; Physiology; Respiratory system; Humor; Pleural diseases EN Anatomy Physiology Respiratory system Humor Pleural diseases 526 526 1 12/15/20 20201201 NES 201201 The pleural space is one of the most slippery mysteries of the body. This is caused by a weakness in the fascia that allows the lung to expand superiorly, the pleura stretching with the lung. The pleura may aid lung inflation by assisting the mechanical coupling between the lung and the chest wall, the slightly negative pleural pressure at functional residual capacity preventing atelectasis by maintaining positive transpulmonary pressure. Traditional teaching is that the actions of the diaphragm and chest wall expanding with inspiration increase the negative pleural pressure, drawing air into the lungs.14 Expiration is facilitated in the reverse, with passive chest wall and lung recoil creating a positive pleural pressure, driving air from the lungs. [Extracted from the article]

Examines the microwave dielectric properties of CaTiO&sub3;-CaAl&sub1/2;O&sub3; ceramics doped with Li&sub3;Nb&subO4; solid solutions. Effectiveness of lowering sintering temperature of ceramics; Properties of solid solutions in the system; Measurement of bulk densities using Archimedes principles.

Examines the effects of heat treatment on the surface microstructure and mechanical properties of MoSi&sub2;-TiC&sub0.7;N&sub0.3; composites. Performance of scanning electron microscopy; Observation of Archimedes principle; Evaluation of indentation fracture method.

Abstract: The exothermic curing reaction of epoxy resins comes along with chemical shrinkage of the material. There do not exist established standard methods for determining the chemical shrinkage during the curing process. To this end, shrinkage measurements based on Archimedes' principle have been carried out for pure epoxy resin at different curing temperatures. In order to model the shrinkage behavior, these results can be related to the curing kinetics. For this purpose, additional DSC measurements have been carried out. (© 2017 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The article focuses on the Cartesian diver, a scientific apparatus. The Cartesian diver is an application of Boyle's law, Pascal's principle and Archimedes' principle. The diver also involves the application of the law which states that pressure in a liquid is proportional to depth if a tall graduate is used in the place of a bottle. If a graduate is used as the container it is noticed that the diver goes to the bottom by the application of pressure and remains there even after the pressure is removed. By decreasing the air pressure below normal air pressure the diver can be made to rise to the surface. With proper adjustments the diver can be used to show another law. The volume of air inside the diver changes with a change in temperature. This results in a change in the buoyancy. This phenomenon illustrates the temperature-volume gas law.