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Currently, classical methods for the creation of various shapes and bending angles of metal sheet parts are applied. They are represented by the so-called all-metal forming tools. Non-standard methods, which in some cases exceed conventional technical solutions, are used in the practice to a minor extent. This is an area of interest from the point of view of ecology, because the shaping process performed in this way does not burden the environment in any considerable way. The knowledge presented in this work is obtained based on experiments in laboratory conditions. The list of literature contains mainly works from the recent period. The research represents a contribution to the great mosaic of magnetism. The aim of the current paper is to also verify the possibilities of the suitability of a special tool in the formation of metal sheet specimens using the application of the so-called forming with a free core. Additional benefits of the experimental work and their results are anticipated. The contribution is complemented by detailed calculations and diagrams. The practical contribution and research is that the device used for forming has been successfully tested. It turns out that the presented method is suitable for further development. The method has proven that is it suitable for industrial applications where simple shapes are produced. [ABSTRACT FROM AUTHOR]

Head injuries are dangerous injuries that are common in combat sports. Nevertheless, the mechanisms of concussion in sport have are not precisely known. Thus, this study aimed to investigate the dynamic response of the head based on linear and rotational accelerations in boxing using computer simulation. The ADAMS software model was used to determine the linear and rotational acceleration of boxing’s straight punch. The peak linear acceleration, average linear acceleration, peak rotational acceleration, and average rotational acceleration resulted from the straight punch to head were obtained: 75 g, 20 g, 4036 rad/s², 1140 rad/s², respectively; the impact times were 30 ms and 3 ms, respectively. The comparison of acceleration tolerance thresholds of head injury and obtained results of this study showed the rotational acceleration only leads to head injury. Furthermore, it is biomechanically improbable that the head would be moved only translationally or rotationally as a result of a straight punch. Therefore, both rotational and linear accelerations should be observed together for future studies.

Coaches and athletes need to understand the kinematics and dynamics of karate kicks to improve the training process and results. The research was aimed at studying the automatic recognition of punches in karate using only linear acceleration sensors. Accelerometers were part of the Inertial Measurement Units (IMUs), which were attached to the left and right wrist of the athlete. To develop a model of punches, highly qualified athletes with 3–7 years of karate experience participated in the research. We analyzed the acceleration fields of various karate punches: Yun Tsuki, Mawashi Tsuki, Age of Tsuki, Uraken. We have proposed more straightforward approach to extracting features without calculating their statistical characteristics. To solve the classification problem, we have used various architectures of convolutional neural networks: multilayer perceptron, 1- and 2-dimension Convolution Networks. Since the recognition of punches was carried out in the conditions of a shadow fight, in addition to the recognition of punches, another output parameter was introduced – movement without punches. Studies have shown a high level of punch recognition based on the developed models. The multi-class accuracy value is 0.96, and the average F1 value is 0.97 for five different punch classes. Thus, the proposed approach is more suitable for practical implementation in automatic learning systems.

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]

In this work, a numerical study of the perforation of 6061-T6 aluminum, Titanium Ti6Al4V and stainless steel (Nitronic33) plates by a rigid flat nose punch is carried out. The Johnson-Cook model was used to define the behavior of the material constituting the plate. This homogeneous behavior was coupled with the Johnson-Cook rupture criterion to completely predict the perforation process. Initially, the present results are validated by comparing them with the results reported in the literature, including those obtained from experimental work. Thereafter, several numerical parametric analyses are performed to investigate the behavior of these metal plates depending on the maximum breaking force, the temperature in the perforated plates, the kinetic energy, the clearance on the shape of the sheared edge, and the dimensional accuracy of the plates. [ABSTRACT FROM AUTHOR]

Channel extrusion is studied experimentally for hardening materials. Comparison of the experimental and theoretical results shows that the formulas are highly accurate. [ABSTRACT FROM AUTHOR]

Channel extrusion is studied experimentally for nonhardening materials. Comparison of the experimental and theoretical results shows that the formulas are highly accurate. [ABSTRACT FROM AUTHOR]

Formulas are derived for the geometric parameters that characterize the deformation of structural elements in extruded material. Analysis of experimental data and theoretical results shows that the formulas are highly accurate. [ABSTRACT FROM AUTHOR]

Background: To handle the competition demands, sparring drills are used for specific technical–tactical training as well as physical–physiological conditioning in combat sports. While the effects of different area sizes and number of within-round sparring partners on physiological and perceptive responses in combats sports were examined in previous studies, technical and tactical aspects were not investigated. This study investigated the effect of different within-round sparring partners number (i.e., at a time; 1 vs. 1, 1 vs. 2, and 1 vs. 4) and area sizes (2 m × 2 m, 4 m × 4 m, and 6 m × 6 m) variation on the technical–tactical aspects of small combat games in kickboxing. Method: Twenty male kickboxers (mean ± standard deviation, age: 20.3 ± 0.9 years), regularly competing in regional and national events randomly performed nine different kickboxing combats, lasting 2 min each. All combats were video recorded and analyzed using the software Dartfish. Results: Results showed that the total number of punches was significantly higher in 1 versus 4 compared with 1 versus 1 (p = 0.011, d = 0.83). Further, the total number of kicks was significantly higher in 1 versus 4 compared with 1 versus 1 and 1 versus 2 (p < 0.001; d = 0.99 and d = 0.83, respectively). Moreover, the total number of kick combinations was significantly higher in 1 versus 4 compared with 1 versus 1 and 1 versus 2 (p < 0.001; d = 1.05 and d = 0.95, respectively). The same outcome was significantly lower in 2 m × 2 m compared with 4 m × 4 m and 6 m × 6 m areas (p = 0.010 and d = − 0.45; p < 0.001 and d = − 0.6, respectively). The number of block-and-parry was significantly higher in 1 versus 4 compared with 1 versus 1 (p < 0.001, d = 1.45) and 1 versus 2 (p = 0.046, d = 0.61) and in 2 m × 2 m compared with 4 m × 4 m and 6 × 6 m areas (p < 0.001; d = 0.47 and d = 0.66, respectively). Backwards lean actions occurred more often in 2 m × 2 m compared with 4 m × 4 m (p = 0.009, d = 0.53) and 6 m × 6 m (p = 0.003, d = 0.60). However, the number of foot defenses was significantly lower in 2 m × 2 m compared with 6 m × 6 m (p < 0.001, d = 1.04) and 4 m × 4 m (p = 0.004, d = 0.63). Additionally, the number of clinches was significantly higher in 1 versus 1 compared with 1 versus 2 (p = 0.002, d = 0.7) and 1 versus 4 (p = 0.034, d = 0.45). Conclusions: This study provides practical insights into how to manipulate within-round sparring partners' number and/or area size to train specific kickboxing technical–tactical fundamentals. Trial registration: This study does not report results related to health care interventions using human participants and therefore it was not prospectively registered. [ABSTRACT FROM AUTHOR]

Formulas are derived for the most important parameters of channel extrusion. [ABSTRACT FROM AUTHOR]

Follicular unit extraction (FUE), now named as follicular unit excision, is one of the methods of harvesting hair follicles from the donor area for implanting in the recipient area. The occipital scalp area is the most common donor area, but nonscalp donor areas like beard, chest, and other hairy body parts can be used as donor hair follicle area. The extraction of the hair follicle leaves a tiny circular scar over the donor area. Over the past 20 years, various devices for FUE have been developed, starting from manual, simple motorized to highly advanced motors with rotation, oscillation, and vibration. Similarly, different types of punch are used: dull, sharp, ultrasharp, serrated, hybrid and specially designed punch blade for long hair follicles harvesting in various diameters from 0.7 mm to 1.1 mm. The follicles can be harvested either by manual method or by motorized method. [ABSTRACT FROM AUTHOR]

From the point of view of environmental protection, it is reasonable to stop using disposable tableware that has been made from polluting plastics and to start using biodegradable and compostable products. Biodegradable and compostable tableware is significantly more environment and nature friendly than disposable plastic tableware and drinkware. The by-products (mostly bran) from the milling of wheat, corn and rice and palm leaves are used for the production of tableware. In the Baltic States, including Estonia, it is reasonable to use wheat bran, rye bran and buckwheat bran and the mixtures of these brans. The aim of this research was to provide the technical and technological know-how for the production of environment friendly disposable tableware and to verify the suitability of the new technological means. In order to achieve the aim, a punch and a die were modelled to produce disposable plates with desired parameters, materials and work modes for the material were chosen and, thereafter, the plates were produced from bran using a physical punch and die and using a suitable moulding mode or temperature and compression duration and using prescribed compressive forces. The mechanical properties like density and flexural strength of the moulded plates were determined.

The work is devoted to solving the axisymmetric problem of the theory of pressing porous bodies with practical application in the form of force calculation of metallurgical processes of briquetting small fractional bulk materials: powder, chip, granulated and other metalworking wastes. For such materials, the shape of the particles (structural elements) is not geometrically correct or generally definable. This was the basis for the decision to be based on the continual model of a porous body. As a result of bringing this model to a two-dimensional spatial model, a closed analytical solution was obtained by the method of jointly solving differential equilibrium equations and the Guber-Mises energy condition of plasticity. The following assumptions were adopted as working hypotheses: the radial shear stress is equal to the tangential one, the lateral pressure coefficient is equal to the relative density of the compact. Due to the fact that the problem is solved in a general form and in a general formulation, the solution itself should be considered as methodological for any axisymmetric loading scheme. The transcendental equations of the deformation compaction of a porous body are obtained both for an ideal pressing process and taking into account contact friction forces. As a result of the development of a method for solving these equations, the formulas for calculating the local characteristics of the stressed state of the pressing, as well as the integral parameters of the pressing process are derived: pressure, stress, and deformation work.

This kind of discourse has some specific characteristics in terms of its creation and language use. A qualitative study was conducted with the data source from stand-up comedy records. The data were reduced to obtain the funniest humor discourse. Furthermore, the data were analyzed based on the creation technique and the construction elements of humor discourse in terms of linguistic and non-linguistic context. The research findings showed that the creation technique and the construction elements of stand-up comedy humor discourse in local perspective in Indonesia were in line with the general concepts and theories of humor discourse creation techniques namely: (a) rhetoric, (b) tone variation, (c) irony, (d) language misunderstanding, (e) wordplay, (f) verbal jokes, (g) sarcasm, (h) satire, (i) sexual satire, and (j) deception. In addition, the results confirmed that the most widely used of creation techniques were rhetoric, wordplay, and deception. The three techniques are more pronounced than other techniques due to the local comics circumscribed public speaking capability.

Attention focuses on determining the deformed state of the workpiece in free channel extrusion. The formulas obtained permit calculation of the accumulated strain at a specified point of the plastic-deformation region and the extruded channel walls for any working path of the punch. [ABSTRACT FROM AUTHOR]

Attention focuses on determining the deformed state of the workpiece in free channel extrusion. The formulas obtained permit calculation of the accumulated strain at a specified point of the plastic-deformation region and the extruded channel walls for any working path of the punch. [ABSTRACT FROM AUTHOR]

The current study investigated the influence of incorporation of graphene nanoplatelets (GNPs) on quasi-static behavior of composite and fiber metal laminate (FML) panels. The unmodified and modified composite specimens and FML panels with 2/1 configuration were fabricated using a hand lay-up method and investigated through a quasi-static punch and indentation testing. The two sets of tests were conducted with a flat-ended indenter and the loading conditions were the same for all samples, except support spans which were varied. Following experimental testing, possible damages at the punch region were closely investigated and localized and global damages were observed. The results revealed that adding 0.2 wt% GNPs improved the strength and fracture toughness of specimens by delaying the failure modes. On the contrary, GNPs made the bonding between the aluminum and composite interface to weaken. [ABSTRACT FROM AUTHOR]

On the basis of the complete set of plastic-flow equations, the extrusion force, the maximum pressure at the matrix wall, and the wall height in channel extrusion are determined, taking account of the elastic deformation of the matrix. [ABSTRACT FROM AUTHOR]

Copyright of Movement & Sport Sciences / Science & Motricité is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As tattoos are both drawing and text that imprint the epidermis in inky arabesques of Delphic symbolism, Punch or The London Charivari acted, for more than one-hundred and sixty-one years (1841-2002) as the sharply witty, bitterly satirical chronicle of its own time. With a weekly circulation of approximately 50,000 – 60,000 issues in the mid-Victorian period, Punch became one of the most influential journalistic witnesses in mid-Victorian Britain, renowned for its unique sense of humour, audacious approach to current social and political matters and, most of all, for an unprecedented mastery of caustic illustrations, in a fresh approach to capture and caricaturise the spirit of the epoch, equally unprecedented in its dynamism and expansion. Although throughout the 1840s the magazine built its popularity more on political analysis than on satirical drawing, ”Punch's Pencillings” would turn the magazine into a vivid fresco, whose inimitable touch and magnetism have come to be osmotically associated with John Leech (1817-1864). With his undeniably remarkable artistic touch he managed not only to define the overall architecture of the magazine, but also to create a new understanding of humorous drawings, introducing the world to the concept of 'cartoon' as we all know it today. This article examines a selection of his three-thousand drawings published in Punch, in an attempt to recompose, through curved charcoal lines, the jigsaw of what Henry James coined as “newspaperized world,” at times when, as Lucy Brown argues, Britain was forging the modern concept of news. It is not only the social, cultural and political milieu that interests us, but also the extratextual implications of a visual appearance and narrative that pervaded the literary scene, as nineteenth-century journalism shared its boundaries with the realm of literary fiction.

Victorians were obsessed with animals and used them pervasively in fiction and press as proxies for human races. This article attempts to analyse the animal display as a political commentary in the visual images of Punch or The London Charivari Magazine in the aftermath of the 1857 Mutiny and the growing geopolitical tensions worldwide. In exhibiting and displaying such animals as the lion, the tiger, the crocodile and the bear while dealing with colonial issues, the popular British cartoons acted as complex rhetorical structures that helped to powerfully influence mass opinion and consequently harnessed the public support for the Empire. Non-human animals were not just used for rhetorical purposes: beasts provided their very bodies to fund and fuel imperial projects, carried administrators and armies across and into remote spaces, and instilled fear and fascination in colonized and colonizers alike. While the scholarship recounting this relationship is not new, recent studies built on pioneering environmental and cultural histories (re)introduced many of the salient topics related to the showcasing of animals and imperialism such as conquest, disease, breeding, scientific categorization, animal welfare, vivisection, zoos, hunting, and conservation.

On the basis of the complete set of plastic-flow equations, the kinematic and stress state of workpiece in channel extrusion is determined in the case of plane deformation when the punch and matrix are misaligned (noncoaxial). [ABSTRACT FROM AUTHOR]

Punches without the use of instruments/objects are a common type of body violence and as such a frequent subject of medicolegal analyses. The assessment of the injuries occurred as well as of the potential of the assault to produce severe body harm is based on objective traces (especially the documented injuries of both parties involved) as well as the—often divergent—descriptions of the event. Quantitative data regarding the punching characteristics that could be used for the assessment are rare and originate mostly in sports science. The aim of this study was to provide physical data enabling/facilitating the assessment of various punching techniques. A total of 50 volunteers took part in our study (29 males and 21 females) and performed severe punches with the fist, with the small finger edge of the hand (karate chop), and with the open hand with both the dominant and the non-dominant hands in randomized order. The strikes were performed on a boxing pad attached to a KISTLER force plate (sampling frequency 10,000 Hz) mounted on a vertical wall. The punching velocity was defined as the hand velocity over the last 10 cm prior to the contact to the pad and ascertained by using a high-speed camera (2000 Hz). Apart from the strike velocity, the maximum force, the impulse (the integral of the force-time curve), the impact duration, and the effective mass of the punch (the ratio between the impulse and the strike velocity) were measured/calculated. The results show a various degree of dependence of the physical parameters of the strikes on the punching technique, gender, hand used, body weight, and other factors. On the other hand, a high degree of variability was observed that is likely attributable to individual punching capabilities. In a follow-up study, we plan to compare the "ordinary" persons with highly trained (boxers etc.) individuals. Even though the results must be interpreted with great caution and a direct transfer of the quantitative parameters to real-world situations is in general terms not possible, the study offers valuable insights and a solid basis for a qualified forensic medical/biomechanical assessment. [ABSTRACT FROM AUTHOR]

Theoretical analyses of extrusion are reviewed in the case where the punch and matrix are misaligned. It is found that the formulas obtained do not permit successful design of extrusion processes. [ABSTRACT FROM AUTHOR]

Deep drawing is one of the important sheet-forming processes. Several process parameters are responsible for producing defect-free products of deep drawing. Out of those parameters, blank holder force is one of the widely studied process parameters, which significantly influence deep drawing. In the present study, the effect of velocity of the punch on deformation behavior of aluminum alloys is investigated. FEM simulation is conducted using commercially available software ABAQUS. It is found through FEM simulation that effective stress increases by nearly 56% with an increment in punch velocity from 150 to 350 mm/s. Besides this, equivalent plastic strain increases by five times on increment in punch velocity from 150 to 350 mm/s. von Mises stress and equivalent plastic strain found to be maximum at flange radii region (die corner) at all velocities of punch. Wrinkling is found to be absent during deformation (loading step) at all punch velocities. Wrinkling is obtained in deep drawn cups after unloading of the punch at all punch velocities except the lowest velocity of 150 mm/s. The phenomenon of wrinkling was found to be pronounced with increment in velocity of the punch after unloading of the punch. For prevention of wrinkling tendency during deep drawing, the velocity of punch should be less than 200 mm/s. Besides this, punch force, effective stress, and equivalent plastic strain found to increase nonlinearly due to increment in punch stroke. It is gathered through FEM simulation that wrinkling phenomenon increases with increment in punch velocity due to unloading of the punch during deep drawing. [ABSTRACT FROM AUTHOR]

On the basis of archival sources and Chronicles of hostilities in the Black sea, data on the actions of assault and fighter aircraft of the black sea fleet air force and the 4th air army on sea targets, ports of the South-Eastern Crimea and their infrastructure when trying to evacuate the retreating German-Romanian troops in the second decade of April 1944, at the beginning of the Crimean strategic offensive.

Currently, classical methods for the creation of various shapes and bending angles of metal sheet parts are applied. They are represented by the so-called all-metal forming tools. Non-standard methods, which in some cases exceed conventional technical solutions, are used in the practice to a minor extent. This is an area of interest from the point of view of ecology, because the shaping process performed in this way does not burden the environment in any considerable way. The knowledge presented in this work is obtained based on experiments in laboratory conditions. The list of literature contains mainly works from the recent period. The research represents a contribution to the great mosaic of magnetism. The aim of the current paper is to also verify the possibilities of the suitability of a special tool in the formation of metal sheet specimens using the application of the so-called forming with a free core. Additional benefits of the experimental work and their results are anticipated. The contribution is complemented by detailed calculations and diagrams. The practical contribution and research is that the device used for forming has been successfully tested. It turns out that the presented method is suitable for further development. The method has proven that is it suitable for industrial applications where simple shapes are produced.

This article presents the development of an experimental methodology that aims to improve the speed of the front-hand punch in karate. The rationale behind developing this methodology is that the speed of the front-hand punch in karate is one of the most important criteria for the successful defeat of the opponent. In addition, the front-hand punch is one of the most commonly used punches during matches. The objective that we set was to study the effect of the application of the methodology we developed for the purpose of improving the speed of the front-hand punch (Kizami Tsuki) in karate. To accomplish this study, we used a computerized video system to register and analyze the speed of karate punches performed by the participants in the experiment. The results regarding the speed of the straight-hand punch were measured in the same way in order to provide identical conditions. Input data was processed by means of applied software for kinematic analysis. To prove the credibility of the registered data, we used statistical analysis methodology. We hope that by presenting our methodology in this article, more coaches will begin to use modern tools and methods in order to improve the quality of training in karate.

PURPOSE The purpose of this study was to investigate the effect of 16-week boxing-specific training on specific fitness and punch power in Korean national team boxers. METHODS Elite male amateur boxers (n=15) from the Korean national team participated in the study. Weight categories of the participants were light fly, fly, bantam, light, light welter, welter, middle, and light heavy. This boxing-specific training program was designed to improve strength and power, and punching power during pre-season for elite boxers. Boxing-specific training program was composed of three parts; power circuit training, tubing and ball training, and boxing power shuttle-run. The specific fitness such as strength and power and punch power were evaluated before, at the mid-way (8-week), and after the training for all the study participants. RESULTS As for maximum strength, there were significant improvements in bench press and squat between pre- and post-training. Both the absolute and relative strength of trunk flexion and extension were improved in the post-training compared to the pre-training. Right and left isokinetic power were also improved at the post-training compared to the pre-training. Punch power for facial straight and hook attacks showed significant improvement at the post-training compared to pre-training. Straight punch power was significantly related to the bench press (r=.515, p=.001), and the right arm extension power (r=.535, p=.001). Hook punch power was significantly related to the right arm extension power (r=.417, p=.006). CONCLUSIONS In conclusion, boxing-specific training was effective to the improvement of strength, power and punch power for elite amateur boxers.

The article introduces into scientific circulation a unique matrix for the production of golden or silver plaques in the Scythian animal style, which was discovered at the Bilsk forthill. On the working surface of the matrix there is depicted a horse with bent legs and a bowed head. Analogical working tools from Dnieper, North Caucasus and Balkan regions are analyzed. There is only one analogy to the image on the matrix among products originated from Eastern Europe: golden plates of the horse’s bridle from Kelermes kurgan № 4. On this basis the matrix is dated the 7th century B.C. Further plot, iconographic and stylistic analogies allow us to conclude that the horse images from the Bilsk matrix and Kelermes plates is matched with the Central Asian images of horses, in particular those placed on deer stones of Mongolia, Tuva and Altay. It’s argued that the matrix could have reached Bilsk settlement together with one of the waves of Scythian migrants from Central Asia, or could be produced by a local master familiar with the Central Asia tradition of depicting a horse. Considerations about semantics of the image of a horse in the Scythian funeral ceremony are represented.

Head injuries are dangerous injuries that are common in combat sports. Nevertheless, the mechanisms of concussion in sport have are not precisely known. Thus, this study aimed to investigate the dynamic response of the head based on linear and rotational accelerations in boxing using computer simulation. The ADAMS software model was used to determine the linear and rotational acceleration of boxing’s straight punch. The peak linear acceleration, average linear acceleration, peak rotational acceleration, and average rotational acceleration resulted from the straight punch to head were obtained: 75 g, 20 g, 4036 rad/s², 1140 rad/s², respectively; the impact times were 30 ms and 3 ms, respectively. The comparison of acceleration tolerance thresholds of head injury and obtained results of this study showed the rotational acceleration only leads to head injury. Furthermore, it is biomechanically improbable that the head would be moved only translationally or rotationally as a result of a straight punch. Therefore, both rotational and linear accelerations should be observed together for future studies. [ABSTRACT FROM AUTHOR]

Copyright of Cahiers Victoriens & Edouardiens is the property of Presses Universitaires de la Mediterranee and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• 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]

Punching in boxing requires a combination of force and velocity of the acting arm, originating from an optimal synchronization of the different body segments. However, it is not well-understood what kinematic parameters of the punching execution influence boxing performance the most. This study aimed to investigate the differences in punching execution between 15 potential Olympic medalist boxers (Elite group) and 8 younger well trained boxers (Junior group). Each athlete was equipped with an instrumented suit composed of 17 inertial measurement units (IMU) and were asked to perform several series of 3 standardized punch types (cross, hook, and uppercut) with maximal force. Linear velocity, stability, and punch forces were computed from the different sensors. Our findings show that Elite boxers systematically produced more force and at a higher velocity for the three punch types compared to Juniors. Further analysis revealed differences in joint contributions between Elite and Juniors, Juniors presenting a higher contribution of the shoulder for the three punch types. Finally ground reaction force imbalance between the front and rear foot was revealed in the cross only, in all boxers (60.6 ± 24.9 vs. 39.4 ± 24.9% and 54.1 ± 7.1 vs. 45.9 ± 7.1%, p ≤ 0.05, for the front vs. rear foot in Elite and Juniors, respectively) but not different between groups. These results have important implications for practitioners involved in the talent identification process, longitudinal follow-up, and training of boxers.

The stamping of eyelets in brackets by plastic deformation is analyzed. The eyelet geometry and the basic requirements on the stamping process are determined. The force required for deformation of the metal in final shaping is established. [ABSTRACT FROM AUTHOR]

Milling picks for road milling machine are considered as equipment which must meet the most stringent requirements associated with fatigue and static strength. Therefore, majority of modern milling picks are manufactured while using high-quality steels alloyed with manganese and chromium. In order to extend service life of the picks for the road milling machine they are supplemented with carbide inserts soldered to the head. In this connection, an application of high-speed hot extrusion technology which has already proved itself in a number of investigations as a highly efficient technology for obtaining precise billets for tools with increased mechanical properties, manufacture of road milling picks, is a very promising direction of the research. The aim of the research is to create a computer model for high-speed hot extrusion in order to intensify a process pertaining to development of technology for manufacturing bimetal picks for road milling machines and to compare the obtained results of modeling and experimental studies. A comparative analysis of the plastic flow in real and model samples has shown that the obtained models provide a qualitative and reliable picture of the plastic flow in the process of highspeed hot extrusion. Modeling in DEFORM-3D eliminates complicated calculations and significantly reduces a number of experimental studies while developing new technological processes.

The formulas here proposed may be used to take account of how the hardening of deformable material affects not only the stress state and forces in extrusion but also the results of the process. [ABSTRACT FROM AUTHOR]