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This study investigated the impact of openings on the punching shear strength of 'non-coarse aggregate acrylic polymer concrete' (APC) slabs. Twelve specimens representing scaled models of a flat, with different parameters such as concrete type, opening size, and distance from the column edge. The specimens were divided into five groups, including a control group of normal strength concrete and APC specimen without openings, as well as APC specimens with various opening sizes and distances, along with APC enhancement specimens. Experimental results were validated using Abaqus finite element software, demonstrating good agreement between the experimental and simulated outcomes. The analysis encompassed several aspects, including load-deflection response, ultimate loading capacity, post-ultimate loading capacity, failure patterns, and strain distribution. The absence of coarse aggregate in APC significantly impacted its shear resistance, leading to a reduction in internal friction. Compared to ordinary concrete slabs, the ultimate capacity of APC slabs without openings was approximately 36% lower. The presence of two openings adjacent to the column further decreased the ultimate capacity by approximately 33%. The size and distance of the openings played a crucial role in determining the ultimate capacity of APC slabs. Notably, the APC specimens exceeded the design ultimate load calculated by Egyptian Code of Practice (ECP-203-2020) and ACI-318-19 codes by approximately 1.4 and 1.6, respectively. However, the study advises against relying solely on APC in shear-sensitive constructions without integrating additional enhancements for shear resistance, as the results indicate a significant reduction in the shear resistance compared to ordinary concrete slabs. [ABSTRACT FROM AUTHOR]

Pencak Silat is a martial sport that contains elements of strength and artistic beauty. There are several punching, kicking and parrying movements in this sport, and scoring is also based on the type of movement performed. So far, punching and kicking movements are still determined manually. Currently the use of technology in developing this technology is limited, both at the training stage for athletes and competitions. This research aims to propose a novel pattern recognition approach for pencak silat punch types classification using supervised learning. This research was carried out in several stages, including hardware design, software design, the process of integrating with the Internet of Things (IoT), data collection, data preprocessing, learning process, testing process, and evaluation process. The data used is primary data by analyzing the pattern of punch movements (xy-axis positions) in pencak silat using hardware and software that has been built. This data is divided into learning data and testing data, which are then used in the learning and testing processes. The learning process uses Self Organizing Map (SOM) and K-Means. The results obtained were the first testing process which was carried out using SOM, obtained accuracy value of 89.00% and an AUC value of 0.91. While accuracy value of the testing process using K-Means obtained an accuracy value of 89.833% and an AUC value of 0.92. It is hoped that the contribution of this research can become a decision support system in determining the type of punch in pencak silat. [ABSTRACT FROM AUTHOR]

This paper investigates the squeeze film behavior of a rigid indenter punch with parabolodial surface profile which interacts with a thin, soft, linearly elastic layer through a thin lubricant film. The layer has infinite radial extent and is either bonded or unbonded to a rigid foundation. Slow and fast squeeze film regimes of lubrication are defined and delineated based on the dry contact radius of a spherical indenter and the radial extent of the lubricant film. Favorable agreement with relevant experimental studies supports the formulation method and regime classification. • New insights on elastohydrodynamic squeeze films with soft materials. • Novel results for a lubricated indenter punch onto unbonded and bonded elastic layers. • Novel classification of slow and fast squeeze regimes of lubrication. • Good agreement of numerical results with available experimental evidence. • Results may be useful for footwear design and biological tissue lubrication. [ABSTRACT FROM AUTHOR]

• Coupling contact model is established for thermoelectric materials. • Full-field analytical solutions in electric and temperature fields are derived. • Thermoelastic governing equations subjected to equivalent external loadings are solved. • Useful evaluation formulas are given for measuring the thermoelectric parameters. • The compressive stress becomes tensile when the thermoelectric load increases. Thermoelectric materials can harvest heat and turn it into electricity and vice versa, which could lead to more cost-effective devices and appliances. This article investigates the problem of electrical and thermal rigid punch acting on thermoelectric materials. Some full-field quantities are given in a closed form. Importantly, some useful formulas for measuring the thermoelectric parameters by the indentation test are given. The nonlinear temperature due to thermoelectric effects can be expressed in convolutional form. For the elastic field, the surface contact stress and the stress intensity factors can be numerically evaluated. Meanwhile the convergence analysis of numerical calculation is conducted. The effects of the thermoelectric loads on the surface contact stress are detailed. The current research is not only beneficial to measuring the thermoelectric coupling properties of thermoelectric materials through punch experiments but also contributes to a deeper understanding of the contact behavior. [ABSTRACT FROM AUTHOR]

Sticking is a common observation in the scale-up stage on the punch tip using a commercial tableting machine. The difference in the total compression time between a laboratory tableting machine and a commercial one is considered one of the main root causes of scale-up issues in the tableting processes. The proposed “Size Adjusted for Scale-up punch” can be used to adjust the consolidation and dwell times for commercial tableting machine. As a result, the sticking phenomenon is able to be replicated at the pilot scale stage. As reported in this article, the quantification of sticking was done using a 3-D laser scanning microscope to check the tablet surface. It was shown that the sticking area decreased with the addition of magnesium stearate in the formulation, but the sticking depth was not affected by the additional amount of magnesium stearate. It is proposed that the use of a 3-D laser scanning microscope can be applied to evaluate sticking as a process analytical technology tool, and so sticking can be monitored continuously without stopping the machine. [ABSTRACT FROM AUTHOR]

In the framework of the finite element method, an approach to the solution for the contact interaction problems for elastoplastic deformable bodies with considering friction in the contact zone is implemented. The geometrically nonlinear approach to the description deformation based on the definitive relationship between the increment of true stresses and deformations, a static statement is given for elastoplastic problems in three-dimensional structures, which have complex geometry. The algorithm of the solution is drawn based on "modified Lagrangian approach" to describe the motion. The problem of body deformation of steel sheets which involve clinch connection, and sample in under punch has been solved, also the distribution of residual stresses in the zone of the clinch joint has been determined. [ABSTRACT FROM AUTHOR]

To reach the sufficient strength of threaded connection it is necessary to make 3 or more turns of the thread. In bars with the thickness of less than 2 mm the length of screwing is reached by sheet bending, connection pressing, cold stamping and other ways, which demand time requirements, additional operations, technical equipment, workforce. The article shows the way of making thread holes by rotating the punch in sheet blanks. There are five steps of the process being held. The following steps of forming holes are used these ways: with constant load and forced feed. The influence of bar thickness and forced feed on geometry of flanging: height and thickness of upper and lower extracting bases has been considered. The experimental data suggest that reducing the bar thickness, the height and thickness of upper and lower flanging bases. Herewith on bars with 5 mm thickness upper extracting is not being formed. Feed increasing causes reduction of height and increase in thickness of the upper and lower flanging. It can be seen on bars with all kinds of thickness (0,5...2,0 mm). The calculated and actual strength of the gained threaded connection on slice is submitted. Also it is clear that the actual strength of the gained threaded connection is higher than the calculated one, because of increasing micro hardness in the threading zone. The result of micro hardness measuring is assumed. To indentify the opportunity of using this method in industry the field of dissipation of the gained diameter was spotted in comparison with the limits by GOST 16093-2004. Also the gained hole corresponds to the 7th limit of accuracy of the inner thread diameter, what allows using this method in the industry [1-7]. [ABSTRACT FROM AUTHOR]

This paper investigates the two-dimensional sliding frictional contact of an elastic solid in the plane strain state based on the theory of the couple stress elasticity. This theory introduces the characteristic material length in order to describe the size effect caused by the underlying microstructure. The Coulomb type friction is assumed in the analysis. The size-dependent contact problem of the rigid flat, cylindrical and parabolic punches is formulated in terms of the Cauchy singular integral equation of the second kind. Then, it is solved numerically to determine the distribution of the normal contact stress and in-plane stress at the contact surface. The effects of the small scale parameter and the friction coefficient on the surface normal and in-plane stresses are discussed in detail. It is found that the contact stress predicted by the couple stress elasticity shows a significant departure from that predicted by the classical elasticity for the half-plane subjected to the same punch and load. [ABSTRACT FROM AUTHOR]

With the interest for the technological options that were taken by the prehistoric groups to subsist, there is a field of research left empty in terms of archaeological records dated to the 8th and 7th millennia cal BC. It concerns the tool kit made from bone and antler used in Europe by stone knappers to work the lithic raw material by pressure and indirect percussion. Based on morpho-technological aspects, this paper presents a first list of recognized archaeological osseous artefacts employed in indirect and pressure lithic reduction. These are punches, pectoral and shoulder sticks, as well as bone elements involved in the lever systems. This investigation is made in the frame of a larger research project aiming at discussing both origin and agent responsible for the introduction of the “inset technology”—conical core pressure blade concept together with the slotted bone tools—appearing in the southern Scandinavia at ca. 7300 cal BC. Results are promising and experiments enabling characterization of the bone and antler tools used in the debitage by pressure and indirect percussion will be soon undertaken. [ABSTRACT FROM AUTHOR]

The article presents the results of measurements impact taekwondo athletes to the board which opens after hitting stroke. Measured values are compared with the results of scientific studies that dealt with human head injuries due to the impacts of various kinds. Most often, these results were determined using cadavers bodies. Force action of the athletes on board was realized by direct punches which are combat sport led to facial parts of opponent. In their own measurement was determined time course of forces impinging on the dynamometer plate including size and direction of the force. Dynamometer measured forces to 10000 N. The frequency was set to 1000 Hz. Estimate of accuracy was 0.5% of measured value. A composite plate was attached to a dynamometer using special steel structures. When comparing the results was found that the combat sport of taekwondo strikes, including other power effects (eg. others combat sports, falls, blows to the head in accidents, etc.) can cause fractures of the facial bones and even other human head trauma or cervical vertebrae. [ABSTRACT FROM AUTHOR]

Hand speed is particularly important in boxing both for protection against incoming blows and delivering blows. Sixteen amateur boxers (10 male, 6 female) with varying levels of experience from a boxing gym performed 20 jabs and 20 cross punches in air. The movement was recorded with a small wrist mounted accelerometer under the glove. The maximum velocity of each punch was determined from the RMS acceleration profile. The mean values of the jab maximal velocity was higher than the cross maximal velocity for 9 participants. The cross showed some dependence on reach (Spearman's correlation coefficient r = 0.57) and the jab dependence on experience (Spearman's correlation coefficient r = 0.56). The accelerometer technique has some promise for routine assessment of fist speed. [ABSTRACT FROM AUTHOR]

Differences between laboratory and commercial tablet presses are frequently observed during scale-up of tableting process. These scale-up issues result from the differences in total compression time that is the sum of consolidation and dwell times. When a lubricated blend is compressed into tablets, the tablet thickness produced by the commercial tablet press is often thicker than that by a laboratory tablet press. A new punch shape design, designated as shape adjusted for scale-up ( SAS), was developed and used to demonstrate the ability to replicate scale-up issues in commercial-scale tableting processes. It was found that the consolidation time can be slightly shortened by changing the vertical curvature of the conventional punch head rim. However, this approach is not enough to replicate the consolidation time. A secondary two-stage SAS punch design and an embossed punch head was designed to replicate the consolidation and dwell times on a laboratory tablet press to match those of a commercial tablet press. The resulting tablet thickness using this second SAS punch on a laboratory tablet press was thicker than when using a conventional punch in the same laboratory tablet press. The secondary SAS punches are more useful tools for replicating and understanding potential scale-up issues. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci [ABSTRACT FROM AUTHOR]

Background: Some vitiligo lesions are resistant to all medical treatments. Objective: We sought to compare the efficacy of hair follicle transplantation and mini-punch grafting for the treatment of refractory vitiligo lesions. Methods: A total of 25 patients with stable and resistant vitiligo participated in the study. In each patient, a resistant vitiligo patch was divided into 2 equal parts. One part was treated with hair follicle transplantation and the other part with mini-punch grafting. Postsurgically, the recipient areas were exposed to narrowband ultraviolet B twice a week for 6 months. The diameter of the repigmentation around each graft was measured monthly. Results: At the end of the sixth month, 68% of follicle grafts, and 72% of mini-punch grafts, had repigmentation. The mean diameter of repigmentation around follicle grafts was 5 ± 1.7 mm and around punch grafts was 5.3 ± 1.6 mm. There was no significant difference between the 2 groups statistically (P = .18). Limitations: Small sample size and short time of follow-up are limitations. Conclusions: Because the results of the 2 methods are not statistically different and mini-punch grafting is much easier to do than follicular transplantation, we recommend mini-punch grafting to treat drug-resistant vitiligo. [Copyright &y& Elsevier]

Scale-up issues in the tableting process, such as capping, sticking, or differences in tablet thickness, are often observed at the commercial production scale. A new shaped punch, named the size adjusted for scale-up ( SAS) punch, was created to estimate scale-up issues seen between laboratory scale and commercial scale tableting processes. The SAS punch's head shape was designed to replicate the total compression time of a laboratory tableting machine to that of a commercial tableting machine. Three different lubricated blends were compressed into tablets using a laboratory tableting machine equipped with SAS punches, and any differences in tablet thickness or capping phenomenon were observed. It was found that the new shaped punch could be used to replicate scale-up issues observed in the commercial tableting machine. The SAS punch was shown to be a useful tool to estimate scale-up issues in the tableting process. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:235-240, 2014 [ABSTRACT FROM AUTHOR]

A pilot study was performed to examine the presence of nerve fibres in minor salivary gland tissue samples obtained by two procedures: punch and linear incisional techniques. The study was undertaken on a convenience sample of five cryopreserved corpses (mean age 74±3.5 years; three males and two females). Biopsies were performed on the buccal side of the lower lip, between the mid-line and the corner of the mouth. Each corpse had one side of the lower lip biopsied by punch and the contralateral side using a linear incision. All punch samples (100%) displayed severed nerve fibres, whereas no nerve fibres (0%) could be identified in the samples obtained by means of the linear incision technique. While the linear incision approach permitted retrieval of at least five glands, punch biopsies did not provide enough material for the diagnosis of Sjögren's syndrome. Within the limitations of the study, our results strongly discourage the punch technique for minor salivary gland lip biopsy and provide information on the superiority of the linear incisional biopsy in terms of neural damage. These results may also promote the undertaking of clinical trials on patients in whom Sjögren's syndrome is suspected, comparing the morbidity associated with the linear incisional technique vs. minimally invasive biopsies. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the thermoelastic frictional contact of functionally graded materials (FGMs) with arbitrarily varying thermoelastic properties. The homogeneous multi-layered model is used to approximate the arbitrarily varying material properties of the FGM coating which is divided into several sub-layers whose material properties is assumed to be constant. It is assumed that a rigid insulated punch is sliding over the surface of an FGM coated half-plane with a constant velocity, which generates frictional heating at the contact interface with its value proportional to the contact pressure, frictional coefficient and sliding velocity. The transfer matrix method and the Fourier integral transform technique are employed to convert the problem into Cauchy singular integral equations which are then numerically solved to obtain the contact stress, in-plane stress and surface temperature. The effects of the gradient index, Peclet number and friction coefficient on the thermoelastic contact characteristics are discussed in detail. Different gradient types of FGMs are considered in numerical examples to compare and identify effective gradient type in suppressing the maximum tensile stress and lowering the maximum surface temperature. Numerical results indicate that thermoelastic contact damage behavior can be changed by adjusting the Peclet number, friction coefficient and their gradient indices or gradient type. [Copyright &y& Elsevier]

Abstract: The AISI D2 tool steel samples and punches were laser cladded with the application of various laser pulse shapes, preheating and cryogenic treatment. The samples were subjected to metallographic observations and sliding wear test and the punches were inserted into the stamping tool and subjected to real operation. The results suggest that the laboratory tests by themselves are not decisive for the prediction of refurbishment wear behavior or failure. The claddings made by A and B pulses exhibited solidification cracking and failed in a punch application test, although their wear results were comparable with the others or even better. The C-type claddings could all be employed for punch refurbishment with the advantage of preheating to mitigate the interpass HAZ cracking. The preheated and cryogenically treated cladding has shown superior edge stability, smooth and ductile wear behavior and moderate interpass cracking. [Copyright &y& Elsevier]

Pressure can sometimes be utilized to increase or decrease the strength of adhesion. This phenomenon is analyzed for upward pull-off of (i) a flat, circular cylindrical punch from a circular plate and (ii) a long, flat, rectangular punch from a long rectangular plate. The pressure is applied, and then the punch is pulled upward. The pressure may act upward (positive) or downward (negative) on the plate. Both force control and displacement control are considered. The plate is assumed to be linearly elastic, and nonlinear von Kármán theory is used to allow moderate displacements. A transversality (debonding) condition is obtained, and the effects of the work of adhesion, the relative size of the punch, and residual stress are investigated. With an increase in pressure, the pull-off force decreases, the pull-off deflection of the punch relative to the initial flat plate level increases, and the pull-off deflection with respect to the pressurized plate may increase or decrease. Some of the results are quite different from those for a membrane (where bending stiffness is neglected). [ABSTRACT FROM AUTHOR]

Abstract: This paper solves the problem of a smooth and frictionless punch on a piezoelectric ceramic layer. Different electrical boundary conditions that employ conducting or insulating punches are presented. The stress and electric displacement intensity factors are used to characterize the electromechanical fields at the punch tip. The field intensity factors are obtained numerically for finite layer thickness. Effects of the thickness of the piezoelectric layer on the stress and electric displacement, and the stress and electric displacement intensity factors at the punch tip are discussed. Solution technique for two identical and collinear surface punches on the piezoelectric layer is also provided and the effect of relative distance between the punches is investigated. Numerical results for some interesting special cases, such as conducting punch and insulating punch, and infinite piezoelectric layer thickness, are presented. [Copyright &y& Elsevier]

Abstract: The ‘plane vs. plane’ contact involving flat punches has been the subject of many investigations, even in recent years, mainly due to the crucial role that such components play in phenomena, such as fretting fatigue and indentation tests. While the problem has been deeply approached from a theoretical point of view, there is a noteworthy lack of experimental verifications due to the limited number of laboratory techniques capable of supplying detailed information about contact parameters. In order to make a partial contribution towards gaining an understanding of such problems, this study proposes the investigation of flat rounded punch contact with an ultrasound-based technique, which exploits the properties of ultrasonic waves to be differently reflected by a contact interface depending on its stress state. A suitable setup was built in such a way as to ensure a good level of control of contact conditions, and the interface was scanned with a high-frequency ultrasonic transducer so as to acquire the reflection data. While the graphic processing of the ultrasonic coefficient of reflection may easily be displayed as a ‘contact map’, the quantitative accuracy of the method was also investigated by comparing experimental results with those obtained from a Finite Element model of the system. The results show a good level of agreement between the two approaches, thus confirming that the ultrasonic technique can be effectively employed to investigate many contact problems which to date have never (or scarcely) been experimentally validated. [Copyright &y& Elsevier]

The volume reduction behaviour of powders has been quantified by means of the ‘in-die’ yield pressure (YP) using Heckel analysis. However, because different YPs are reported for the same material, the experimental conditions influencing this material-constant were investigated. Silicified microcrystalline cellulose was compressed into flat-faced and convex tablets using a compaction simulator instrumented with load and displacement transducers. During compression, upper and lower punch force and displacement data were recorded and corrected for punch deformation. A symmetrical triangle wave compression profile was used and the instantaneous punch velocity was kept constant (5 mm/s). Individual tablet height and weight were used for Heckel analysis. The influence of the ‘effective compression pressure’ (PEFF) (ranging from 10 to 350 MPa), punch diameter (PD) (4, 9.5 and 12 mm) and filling depth (FD) (4.5, 7.5 and 10.5 mm) on YP was statistically evaluated using Response Surface Modelling software. A quadratic surface response equation, describing the relationship between PEFF, PD, FD and YP, was proposed for concave (Adj R2: 0.8424; S.D.: 14.60 MPa) and flat-faced (Adj R2: 0.8409; S.D.: 4.49 MPa) punches. YP and tensile strength were mainly determined by PEFF, irrespective of punch curvature. FD and PD had only a minor influence on the YP, although more pronounced for the concave punches. The method used resulted in reproducible PEFF and tensile strength values and the flat-faced tablets showed less weight variation. Flat-faced punches are preferred over punches with a concave surface when investigating the volume reduction behaviour of a powder by means of Heckel analysis and the experimental parameters should be reported. [Copyright &y& Elsevier]

Tool wear is one of the major concerns in the tooling industry. A comparative evaluation of different tool materials and tool wear will help preventing frequent replacement of tools thus reducing the costs incurred due to such replacements. In this paper, tool wear mechanism of tetragonal zirconia polycrystal (TZP) punch is compared with that of commercially available WC (tungsten carbide) punch during stamping. The tool life for the TZP punch was found to be over 2.5 times higher than that of commercial tungsten carbide. The worn-out tools were analysed using scanning electron microscope and optical microscope for studying the tool wear mechanisms. Tool wear and chemical action possibly cause the failure of the tungsten carbide punch, whereas wear of TZP punch is predominantly caused by mechanical shearing of asperity and plastic deformation. Due to their inherent high melting point and the absence of the second-phase binder, ceramics materials do not soften at higher temperature unlike the carbide tools. Hence, they can be used at high cutting speeds without initiating deformation/diffusion wear. This assists in improving the tool life significantly. In addition, TZP ceramics is inert, corrosion resistant and non-wetting when contacting metals. Exposed carbide grains act as a site for increased wear and metal pickup during precision, high-speed metal stamping and forming. Moreover, cobalt-depleted carbide tools can create burring of the strip being stamped, leading to poor part quality. The performance of TZP punch tool will be evaluated thoroughly based on experimental data in this paper. [Copyright &y& Elsevier]

This paper derives an exact solution for a flat smooth punch applied on a piezoelectric half plane. The piezoelectric solid occupies the lower half plane, and a flat rigid punch is applied on it. As the permittivity of the air (environment) is far less than that of the piezoelectric material, the electric induction of air may be neglected. The permittivity of the punch is also far less than that of the piezoelectric material and consequently the normal component of the electric displacement vanishes at the contact boundary. The exact solution is obtained by eigen-function representation and analytic continuation. The distribution of pressure under the punch has been found. The electric field along the surface of the lower half plane is extracted in a closed form. [Copyright &y& Elsevier]

• The mould's failure mode is mainly attributed to locally plastic deformation. • Martensite decomposition leads to a decrease in the surface hardness of the mould. • Plastic deformation is caused by microstructure transformation and hot extrusion force. • It is proved that surface oxides can accelerate mold failure. To explore the evolution of the microstructure, properties, and failure mechanism of a hot extrusion punch during service, a hot extrusion experiment was carried out on a home-designed testing platform, enabling multiple analyses at an elevated temperature of 950℃. The microstructure was evaluated using optical microscopy, scanning electron microscopy, and other analytical methods. The results showed that the punch could continue working 850 times before it failed. The primary failure mode was ascribed to local plastic deformation, accompanied by apparent oxidation and wear at the bottom and working area. The extended analysis also revealed that the ferrite content in the matrix increased in the entire working zone and that the overall microstructure exhibited a fibrous morphology instead of lath features, where the tiny carbide particles were homogeneously distributed. This suggested that significant plastic deformation occurred during service. Moreover, the carbide particles were further fragmented and well dispersed with plastic deformation. [ABSTRACT FROM AUTHOR]

• Four tests of SHSB has been numerically studied, i.e. circular hat-shaped, flat hat-shaped, punch and double-notch. • Shear angles are varied as ± 2.5°, 5°, 7.5°, 10° and 15° and maintaining the input energy and the shear area. • This research shows comparison of the dynamic material characterization's results: stress – strain, final strain, strain rates, force equilibrium, and strain rate gradient. • The results indicate that 5° shear angle is recommended for SHSB's specimen. Dynamic material characterization is one of important factors in the development of modern transportation industry to overcome two main challenges, i.e. lightweight and crashworthy vehicles. The most commonly used apparatus to characterize the material in high strain rates is the Hopkinson bar. The Hopkinson bar can be conducted into several loading conditions such as compression, tension, shear, torsion and multiaxial. This paper focuses on the split Hopkinson shear bar testing, especially on the effect of the shear angles on generating the shear stress – shear strain curves, shear strain rates, and final shear strains. Four geometries of specimen were studied, i.e. circular hat-shaped (CHS), flat hat-shaped (FHS), punch (P) and double-notch (DN). This research is conducted with three main considerations, i.e. the same kinetic energy (7.34 Joule), the same shear area (±25 mm2), and the shear angles were varied as ±2.5°, 5°, 7.5°, 10° and 15°. This study shows that each testing has its own advantages and disadvantages and they generate different strain rate, strain rate gradient, final strain, and shear stress – shear strain relations which is not desirable. In term of shear angles, authors recommend using a shear angle of appoximately 5°. This shear angle generates the best purity on the shear loading among other shear angles and also the flow stress variation (among four tests) are quite acceptable ±16.4%. [ABSTRACT FROM AUTHOR]

• Simple, piecewise polynomial approximations of the load - indentation relation for a linear - elastic layer of an arbitrary thickness indented with a rigid punch are presented. • Layers either free to slip or bonded to the rigid substrate, indented with a conical, paraboloidal or cylindrical punch, are considered. • Numerical solutions of the integral equation representations of the thin layer indentation problem were approximated with piecewise, high order Chebyshev polynomials, and then used as input for the Remez algorithm, producing low - degree polynomial approximations with a uniform relative error. • The proposed approximations have been implemented in an open software AtomicJ to facilitate their use for analysis of force - distance curves recorded with an Atomic Force Microscope. We present simple expressions for load required to indent a layer of arbitrary thickness with a conical, paraboloidal or cylindrical punch. A rigid substrate underneath the sample leads to an increase of load required for indentation. This effect has to be corrected for to prevent overestimation of Young's modulus from indentation measurements, such as force - distance curves recorded with the Atomic Force Microscope (AFM). The problems of the frictionless contact of an axisymmetric punch and an isotropic, linear-elastic layer are reducible to Fredholm integral equations of the second kind. We solved them numerically and used the Remez algorithm to obtain piecewise polynomial approximations of the load - indentation relation for samples that are either in frictionless contact with the rigid substrate or bonded to it. Their relative error due to approximation is negligible and uniformly spread. Combining the numerical approximations with asymptotic solutions for very thin layers, we obtained equations appropriate for samples of arbitrary thickness. They were implemented in a new version of AtomicJ, our free, open source application for analysis of AFM recordings. [ABSTRACT FROM AUTHOR]

• The electrode/punch of thermoelectric materials is studied. • Electric current density and energy flux are obtained in explicit form. • The voltage and temperature underneath the electrode/punch are given in terms of the applied current and energy flux. • The results are helpful in measuring the thermal/electrical properties via electrode/punch experiment. This paper studies the problem of a thermal and electrical electrode/punch on a thermoelectric material layer within the framework of fully coupled, nonlinear thermoelectricity model. The resultant thermal flux and energy current on the electrode/punch are prescribed. Explicit expressions for the thermal/electrical fields at the electrode/punch tip are obtained and are seen to be singular. For infinite layer thickness the thermoelectrical fields are obtained in closed-form. For finite layer thickness, the relationship between the applied flux/current and the voltage/temperature underneath the electrode/punch are obtained numerically by a singular integral equation technique. Effect of layer thickness is discussed. The results are helpful in measuring the thermoelectric coupling properties of thermoelectric materials by electrode/punch experiments. [ABSTRACT FROM AUTHOR]