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The stove tiles from the 15th and 16th centuries discovered in some countries in Central Europe often approach, as decoration, the theme of the medieval knight. The archaeological research carried out on the territory of Romania brought to light a vast and diverse material related to this subject. The present study analyzes three stove tiles discovered in Muntenia – at Târgovişte and Curtea de Argeş, former princely courts and capitals of Wallachia, in the Middle Ages, pieces whose iconographic theme is “the knight in the tournament”. The specimens, chronologically dated between the end of the 14th century and the 16th century, stand out for the original character of the compositions.

This research delves into the design, modeling, and finite element impact analysis of the segmented sandwich composite armor system subjected to impact loading, considering different parameters such as materials to be used, armor height, and armor design configuration. Initial studies were performed to select the ideal model that will provide the best impact resistance at the least weight and with minimal fabrication requirements. Material type, thickness, and overall model configuration were defined during the initial model development period. Once the final design was defined, finite element analysis was performed using 2017 ABAQUS software to observe the performance of the model and to validate the efficiency of the chosen armor. Based on the results from the material selection and thickness validation, the optimal design with the best impact resistance was noted as 1.2 mm thick rectangular segmented silicon carbide tiles, serving as the top layer that covers the three-level gradient core composed of a titanium metal honeycomb frame filled with silicon carbide inserts, and finally a 2 mm thick glass epoxy composite layer made from four laminas in a 0/45/90/-45-degree configuration serving as the last layer of the armor.

This research delves into the design, modeling, and finite element impact analysis of the segmented sandwich composite armor system subjected to impact loading, considering different parameters such as materials to be used, armor height, and armor design configuration. Initial studies were performed to select the ideal model that will provide the best impact resistance at the least weight and with minimal fabrication requirements. Material type, thickness, and overall model configuration were defined during the initial model development period. Once the final design was defined, finite element analysis was performed using 2017 ABAQUS software to observe the performance of the model and to validate the efficiency of the chosen armor. Based on the results from the material selection and thickness validation, the optimal design with the best impact resistance was noted as 1.2 mm thick rectangular segmented silicon carbide tiles, serving as the top layer that covers the three-level gradient core composed of a titanium metal honeycomb frame filled with silicon carbide inserts, and finally a 2 mm thick glass epoxy composite layer made from four laminas in a 0/45/90/-45-degree configuration serving as the last layer of the armor. [ABSTRACT FROM AUTHOR]

In this study, the ballistic resistance of SiC (silicon carbide) and a SiC mixture S80B20 (80% SiC/20% B4C) backed with UHMWPE (ultra-high-molecular-weight-polyethylene) fiber board was investigated by striking it with a.30-06 armor piercing projectile. The front plate of the high hardness ceramics is intended to passivate the bullet and limit the bullet's impact kinetic energy, and the high strength backing plate undergoes plastic deformation, absorbing the bullet's residual energy. Ballistic tests revealed that an 8 mm thick S80B20 ceramics produced at a sintering temperature of 2120° or 2140°C, combined with a composite plate, can successfully resist.30-06 armorpiercing rounds with energy greater than 3900 J. The optimal SiC plate meeting the NIJ 0101.06 Level IV was an 8 mm thick SiC sheet backed with 9 mm of fiber board (total thickness, 17 mm; areal density, 33.217 g/m2). The 8 mm thick 80% SiC/20% B4C plate sintered at 2120°C, backed with 7 mm fiber board, had an areal density of only 29.615 kg/m2. If the depth of penetration is less than 44 mm, the fiber board thickness must be increased from 7 to 8 mm, increasing the areal density to 30.552 kg/m2. Compared with the SiC ballistic plate, the density of the composite is 2.665 kg/m2 lower. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Defense Sciences / Savunma Bilmleri Dergisi is the property of Turkish Military Academy Defense Sciences Institute 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.)

This paper aims to assess how the impact behaviors of multi-ply flexible fabrics change by different projectile impacts using numerical simulations. The paper starts with the generation and verification of a multi-scale finite element model. Subsequently, a ten-ply flexible fabric is numerically subjected to the impacts of six different types of projectiles: 22-caliber conical, spherical, and right circular cylindrical (RCC), as well as 0.30-caliber conical, spherical, and RCC. The remaining sections of the paper explore the ballistic protection behavior of the ten-ply flexible fabric from all aspects, including ballistic limits, changes in energy, displacements, and damage patterns. The research findings suggest that the latter plies of the fabric have significant importance in dissipating energy compared to the initial plies, regardless of the type of projectile impact. This is because the first plies of the fabric tend to fail prematurely and reach their maximum strain limit before they can effectively dissipate energy. Although the initial plies showed consistent trends across all projectiles in terms of energy transfer, the size of the post-damage area and failure modes were influenced by the characteristics of the projectiles. Overall, this research emphasizes the need to explore the ballistic capability of multi-ply flexible woven fabrics impacted by different projectiles to improve both the construction and effectiveness of soft body armor. [ABSTRACT FROM AUTHOR]

Introduction/purpose: In recent times, with the tendency to develop new types of armor-piercing ammunition, constant investments in the development of new types of armored obstacles is necessary. Obstacles made of high-alloy steel plates are still the best form of protection against larger caliber ammunition. There are a number of factors to consider when selecting an alloy, including the weight, dimensions, intended use, desired ballistic performance, and costs. According to that, a numerical analysis of penetration of a 30mm armor-piercing fin-stabilized discarding sabot projectile into the steel alloy Weldox 460 plates of different thicknesses at a distance of 1000m with a velocity of 1300m/s is presented in this paper. Methods: The stresses and deformations of the penetration effect were calculated through numerical analysis and finite element modeling. To specify material characteristics, the Johnson-Cook material model and the fracture of materials model have been utilized. In order to define models and carry out numerical calculations, the software packages FEMAP and LS Dyna have been used in this paper. Results: For a numerical analysis of the penetration process of this projectile type against armor obstacle, four different armor plate thicknesses are calculated: 10mm, 50mm, 100mm, and 110mm. For each of them, the results are shown in a form of stress and displacement, so that the interaction phenomena between the sub-projectile and the armor plate can be described. Conclusion: Modeling the impact on armor-piercing obstacles is extremely difficult, time-consuming, and complex, and the resulting models very successfully (or with some deviation) approximate the real problem of projectile penetration. One of the most effective methods for solving problems of this kind and others of a similar nature in recent times is the finite element method analysis. The material and the target dimensions, as well as the ballistic parameters and the material of the projectile have the biggest influence on projectile penetration. The target's resistance to penetration increases when all input parameters are maintained at the same level and its thickness is increased, and vice versa.

This article examines one of the few prints taking up the Spanish Habsburg cause during the early years of the Eighty Years’ War: Diptych of Christ and Philip II (1568), presumably engraved by Johannes Wierix. Because prints were less commonly used by the royalist side to distribute their propaganda in the Low Countries, this engraving offers a singular view into what the medium afforded them. Examined against the backdrop of iconoclasm, the engraving puts forward a multi-faceted argument about the protection of King Philip II and devotional objects as well as the sacralization of the king and the preservation of the Catholic faith.

This review systematically examines the use of additive manufacturing (AM), also known as 3D printing (3DP), in the various aspects of military applications such as firearms, armor and ballistic resistant structures, including those bioinspired. The main goal is to provide a comprehensive exploration of AM in armor and military applications. The materials and structures created using AM technologies are analyzed and reported. Dynamic loading, and impact via Charpy and Izod tests were also explored in the search, although not considered in the armor results to be tests typically conducted at low strain rates, far from a real ballistic solicitation. Recently, an increase in military applications has been found, particularly gun prototypes fabricated in diverse materials with AM. Although the innovation, low costs, and manufacturing are clear advantages of these devices via 3D printing, there are limitations, such as the worrying panorama of unclear regulations that prevent these weapons from eventually reaching ordinary citizens. Current perspectives, opportunities, and challenges are discussed.

Introduction/purpose: In recent times, with the tendency to develop new types of armor-piercing ammunition, constant investments in the development of new types of armored obstacles is necessary. Obstacles made of high-alloy steel plates are still the best form of protection against larger caliber ammunition. There are a number of factors to consider when selecting an alloy, including the weight, dimensions, intended use, desired ballistic performance, and costs. According to that, a numerical analysis of penetration of a 30mm armor-piercing fin-stabilized discarding sabot projectile into the steel alloy Weldox 460 plates of different thicknesses at a distance of 1000m with a velocity of 1300m/s is presented in this paper. Methods: The stresses and deformations of the penetration effect were calculated through numerical analysis and finite element modeling. To specify material characteristics, the Johnson-Cook material model and the fracture of materials model have been utilized. In order to define models and carry out numerical calculations, the software packages FEMAP and LS Dyna have been used in this paper. Results: For a numerical analysis of the penetration process of this projectile type against armor obstacle, four different armor plate thicknesses are calculated: 10mm, 50mm, 100mm, and 110mm. For each of them, the results are shown in a form of stress and displacement, so that the interaction phenomena between the sub-projectile and the armor plate can be described. Conclusion: Modeling the impact on armor-piercing obstacles is extremely difficult, time-consuming, and complex, and the resulting models very successfully (or with some deviation) approximate the real problem of projectile penetration. One of the most effective methods for solving problems of this kind and others of a similar nature in recent times is the finite element method analysis. The material and the target dimensions, as well as the ballistic parameters and the material of the projectile have the biggest influence on projectile penetration. The target's resistance to penetration increases when all input parameters are maintained at the same level and its thickness is increased, and vice versa. [ABSTRACT FROM AUTHOR]

This article explores the robe/armor removal imagery in the book(s) of Samuel. Through a study of the key instances of robe/armor removal, this article seeks to show how Samuel's imagery develops the theme of Davidic kingship. As will be argued, the narrator uses the literary device of robe/armor removal to attest to the kingly nature of the one before whom a character's robe or armor is removed. In the end, this literary pattern of robe/armor removal will shed light on David's strange, somewhat undignified, "uncovering" in 2 Sam 6. By tracking the use of robe/armor removal imagery, it will be shown that David's robe removal reveals his view that Yhwh is the true king of Israel. [ABSTRACT FROM AUTHOR]

This article provides a detailed account of the conservation process for Tutankhamun's leather scale armor. The armor was in a critical condition and required extensive restoration. Various imaging techniques were used to examine the armor's surface and identify hidden features and defects. Microbiological testing revealed fungal and bacterial infections, and spectroscopy confirmed the presence of previous conservation materials. The conservation procedures included cleaning, separating incorrectly attached scales, straightening the linen support, consolidating textiles, and reconstructing the scales. After conservation, measurements were taken and the manufacturing techniques of the armor were revealed. The article concludes that the conservation methods used were effective and provides recommendations for future projects. [Extracted from the article]

To support the structural optimization design of metal-ceramic armor against penetration protection performance, this paper optimizes the armor in terms of protection material, armor structure, and bullet resistance mechanism, and envisages a new metal-constrained ceramic composite armor, which overcomes the disadvantages of ceramic material fragility. A coupled finite element-smooth particle hydrodynamics (FEM-SPH) algorithm is used to simulate the penetration process, and the influence of ceramic unit shape and size on the armor protection performance is investigated by quantitatively comparing the bullet energy loss, velocity change, penetration depth, and other indicators that reflect the ballistic protection mechanism. The results show that metal-confined ceramic armor has repairable performance, and filling ceramic units can reduce armor failure area, save armor repair time, and extend armor service life. When the velocity of the projectile is less than 500 m/s, the damaged area of the armor filled with small-sized unit ceramics (1/4 bullet caliber) is small and easy to repair; when the velocity of the projectile is greater than 500 m/s, the armor filled with large-sized unit ceramics (2 times the bullet caliber) can effectively increase the bullet residence time and improve the armor's resistance to elasticity. The results of this paper can provide a reference for the optimal design of the armor structure. [ABSTRACT FROM AUTHOR]

Auxetic behavior is a promising new area for use in defense applications. In comparison to a conventional material, an auxetic material has superior properties because of having a negative Poisson's ratio; it gets broadened when stretched or becomes smaller when compressed. Furthermore, auxetic materials have enhanced properties such as shear resistance, indentation resistance, fracture toughness, energy absorption, and so on. These improved properties make auxetic materials very appealing and have the potential to revolutionize their applications in aerospace, sports, automotive, construction, biomedical engineering, smart sensors, packaging, cushioning, air filtration, shock absorption and sound insulation, and defense personal protective equipment. This article examines the most recent scientific advances in auxetic materials and structures, such as auxetic textiles (fibers, yarns, and fabrics), auxetic textile-reinforced composites, and auxetic foams, as well as their exceptional auxetic behavior and various approaches to achieving them. Although many potential applications have been proposed, actual applications of auxetic materials in defense are still limited. This is an in-depth review article, and its main goal is to serve as a foundation for future studies concerning the topic. [ABSTRACT FROM AUTHOR]

Introduction/purpose: Thin plates made of high–strength steel are frequently used both in civil and military ballistic protection systems. In order to choose an appropriate type of alloy, it is necessary to fulfil a number of criteria, such as the condition of use, the desired ballistic performance, weight, dimensions, and price. This paper presents a numerical analysis of the penetration of a 30mm armor-piercing projectile with a velocity of 750m/s into steel alloy Weldox 460 plates of different thicknesses at a distance of 1000m . Methods: The analysis has been performed using numerical methods and finite element modeling to calculate stresses and deformation caused by the penetration effect. For defining material characteristics, the JohnsonCook material model and the fracture of materials model have been used. In this paper, the software packages FEMAP and LS Dyna have been used for defining models and performing numerical calculations. Results: The results of the performed numerical analysis as well as the obtained stress and displacement values are presented for four different armor plate thicknesses: 30mm, 33mm, 34mm, and 40mm. The results show a penetration effect and an interaction between the projectile and the armor plate. Conclusion: Modeling the impact on armor-piercing obstacles is very complex, extensive, and demanding, and the formed models approximate the real problem of projectile penetration in a very successful way (or with a certain deviation). In recent times, the analysis using the finite element method has proven to be one of effective approaches to solving such and similar problems. The material and the dimensions of the obstacle, as well as the material and the ballistic parameters of the projectile have the greatest influence on projectile penetration. Keeping all the input parameters at the same level and increasing the thickness of the target leads to its increased resistance to penetration.

Commonly seen to display military prowess or chivalric virtue, parade armor of the sixteenth century here is considered for its impact on the wearer's own physiology and psychology. Through juxtaposing the ergonomic features of muscle cuirasses and children's harnesses with courtly etiquette rules, humanist educational regimes, and orthopedic devices in medicine, this paper reveals armor's stakes in fashioning the princely body by means of physical discipline rather than visual representation. Plate armor, by "correcting" posture and mannering comportment, aided in molding an exemplary disposition expected to incite subjects to imitation. [ABSTRACT FROM AUTHOR]

Because of their superior mechanical properties, preformed helical fittings are widely used in UHV transmission lines. However, they easily slip and become loose under extreme environments, so it is very important to study the fastening characteristics of preformed helical fittings. According to the stress characteristics of preformed helical fittings, a parametric finite element model including a core and preformed armor rods was established. Finally, the finite element model calculation was verified by comparing it with the test results. In this paper, the influences of the preformed armor rod diameter, pitch, length and forming aperture on the fastening characteristics were investigated. The numerical simulation results showed that the smaller the forming aperture of preformed armor rods, the larger the grip force. However, a small forming aperture is inconvenient to install, and too large of a grip force on the core easily leads to core damage. With the increase in the preformed armor rod length, the grip force increased gradually and linearly, and the increase slowed after the pitch number reached 9. The larger the pitch, the smaller the grip force of the preformed helical fittings. The fastening characteristics of preformed armor rods with slightly larger diameters were better and the fourth power of the diameter of the preformed armor rods has a linear relationship with the grip force. [ABSTRACT FROM AUTHOR]

Introduction/purpose: Thin plates made of high–strength steel are frequently used both in civil and military ballistic protection systems. In order to choose an appropriate type of alloy, it is necessary to fulfil a number of criteria, such as the condition of use, the desired ballistic performance, weight, dimensions, and price. This paper presents a numerical analysis of the penetration of a 30mm armor-piercing projectile with a velocity of 750m/s into steel alloy Weldox 460 plates of different thicknesses at a distance of 1000m . Methods: The analysis has been performed using numerical methods and finite element modeling to calculate stresses and deformation caused by the penetration effect. For defining material characteristics, the Johnson- Cook material model and the fracture of materials model have been used. In this paper, the software packages FEMAP and LS Dyna have been used for defining models and performing numerical calculations. Results: The results of the performed numerical analysis as well as the obtained stress and displacement values are presented for four different armor plate thicknesses: 30mm, 33mm, 34mm, and 40mm. The results show a penetration effect and an interaction between the projectile and the armor plate. Conclusion: Modeling the impact on armor-piercing obstacles is very complex, extensive, and demanding, and the formed models approximate the real problem of projectile penetration in a very successful way (or with a certain deviation). In recent times, the analysis using the finite element method has proven to be one of effective approaches to solving such and similar problems. The material and the dimensions of the obstacle, as well as the material and the ballistic parameters of the projectile have the greatest influence on projectile penetration. Keeping all the input parameters at the same level and increasing the thickness of the target leads to its increased resistance to penetration. [ABSTRACT FROM AUTHOR]

In terms of society and culture the Edo era in Japanese history was a vibrant and rich time. The evolution of Japanese traditional armor technology and armor culture achieved its pinnacle with the entry of Western technology into the contemporary age and the absorption of Chinese culture giving rise to the distinctive Japanese system of Nanban Dō. The Metropolitan Museum of Art in New York the USA has a sizable collection of ancient weapons and armor that spans geographies and covers various historical eras of Asian and European armor including a considerable portion of Japanese armor. This creates objective conditions for the comparison study of Japanese armor structure and form. We summarized and compared the Nanban Dō and the Asian and European armor collections of the Metropolitan Museum of Art in the United States in this article using historical analysis documentary analysis and case study techniques. It is found that the paradigm shift at different stages of the development of Nanban Dō was based on the different ways of acquiring and transforming foreign cultures in the changing contexts of the times and the timely innovation in the later critical acceptance. The following conclusions were obtained from the study. First the paradigm development of Japanese Nanban Dō was related to the level of productivity national military power and aesthetic trends of the times and was also inseparably related to the history of political and cultural exchanges. The paradigm transformation path of design imitation and re-creation of Japanese made Nanban Dō was a process of restatement-transformation-breaking and in this process a vigilance for civilizational assimilation was always maintained. Second East armor and West armor were not separate systems that developed independently of each other. The evolution of the paradigm of the Edo period's Japanese made Nanban Dō was an attempt by craftsmen from various regions to find a scientific balance between the aesthetics of Edo armor at a time when Eastern and Western cultures were colliding fiercely and at the will of the ruling class and in the environment where Western technology and Eastern culture intermingled the Japanese made Nanban Dō exhibited characteristics of an experimental artwork. Third the traditional armor culture of East Asia is a genealogical structure built around China and the in-depth study and development of the Japanese Nanban Dō has positive significance for the study of armor in China and even East Asia. We treat the Metropolitan Museum of Art as a historical environment of multicultural interactions search for internal links in the subtleties summarize and analyze the different formal changes of the Edo period and the Japanese made Nanban Dō paradigm in different historical stages and analyze the progressive development of this form in depth and in all aspects so as to find new possibilities for the study of East Asian armor art. [ABSTRACT FROM AUTHOR]

In this study, a new strategy is adopted for the development of advanced, and lightweight ballistic armor. This new generation of ballistic protections is referred to as "hybrid", in which certain layers of Kevlar have been impregnated with a high-performance green and bisphenol-A free thermosetting resin, namely the vanillin-based benzoxazine (Va-BZ). The role of thermosetting polymer is to slow down and stop the projectile. In addition, the backface signature (BFS) with a minimum number of Kevlar layers is reduced. Indeed, this kind of matrix not only possesses one of the highest crosslinking densities in the field, but also offers excellent mechanical and thermal properties. The adopted experimental approach consists in gradually changing, in increments of 5, the number of impregnated Kevlar layers. The ultimate goal is to reduce the number of Kevlar layers from 26 (currently in use) to 20 while ensuring a BFS of less than 44 mm (as per the requirement of the National Institute of Justice standard NIJ-0101.06). Indeed, the adopted strategy allowed significant reduction in the BFS. For instance, armors made of 20 layers of Kevlar layers in which 10 layers were impregnated by the Va-BZ displayed the minimal BFS value of 36.54 mm. Hence, by introducing the Va-BZ resin, the non-perforated Kevlar fabrics gained enough rigidity to sustain the impact with minimal deformation. Overall, these newly developed armors offer the best BFS possible to protect vital human body parts. [ABSTRACT FROM AUTHOR]

This is the second article in a series devoted to the canonical image of the armed saints in Early Christian, Early Byzantine, Late Byzantine and post-Byzantine iconography. The most representative and distinctive iconographic images, from the point of view of Christian theology, are the faces of soldiers-confessors who became victims of persecution and suffered a painful death in the era of early Christianity. Their image is conceptually different from the bloodless faces of hermits: the soldiers of Christ were among people, relocating from place to place, they knew the world around them well. In appearance, they were not different from the rest of the military, because on frescoes, icons and bas-reliefs they were depicted as physically strong, well-groomed, firm in their intentions men, with noble facial features, dressed in beautiful clothes and having expensive armor. The icon painters seemed to deliberately seek to emphasize the physicality of their image and the close connection with the mortal existence of this world. However, when the dilemma of choosing between a painful confessional death and renunciation of faith for the sake of preserving life or a high social position arose, the love of life of these noble young people did not prevent them from making a choice in favor of the immortality of the soul, to sacrifice the values of the world below for the glory of the throne Above. Over time, the image of soldiers-confessors was transformed: from victims of permanent persecution, religious intolerance and arbitrariness of the Roman authorities, they turned into incarnate soldiers of Christ, defenders of the faith, who joined the ranks of the Heavenly host under the command of Archangel Michael. This explains the iconographic similarity of the images of the earthly Christian warriors and the Heavenly Host. Это вторая статья из серии, посвящённой каноническому образу святых-порубежников в раннехристианской, ранневизантийской, поздневизантийской и поствизантийской иконографии. Наиболее репрезентативными и своеобычными иконографическими образами, с точки зрения христианской теологии, являются лики воинов-исповедников, ставших жертвами гонений и подвергшихся мучительной смерти в эпоху раннего христианства. Их образ концептуально отличается от бескровных ликов отшельников: воины Христа обретались в гуще людской массы, передислоцируясь с места на место, хорошо знали окружающий мир. С виду они ничем не отличались от остальных военнослужащих, потому на фресках, иконах и барельефах изображались телесно крепкими, ухоженными, твёрдыми в своих намерениях мужами, с благородными чертами лица, облачёнными в красивые одежды и дорогие доспехи. Иконописцы словно намеренно стремились подчеркнуть телесность их образа и тесную связь с бренным бытием этого мира. Однако когда вставала дилемма выбора между мучительной исповеднической смертью и отказом от веры ради сохранения жизни или высокого социального положения, жизнелюбие этих знатных молодых людей не препятствовало им сделать выбор в пользу бессмертия души, поступиться ценностями дольнего мира ради славы Горнего престола. Со временем произошла трансформация образа воинов-исповедников: из жертв перманентных гонений, религиозной нетерпимости и произвола римских властей они превратились в воплощённых воинов Христа, защитников веры, пополнивших ряды Небесного воинства под командованием Архистратига Михаила. Этим объясняется иконографическое сходство образов земных воинов-христиан и воинства небесного.

By using split Hopkinson pressure bar, optical microscopy and electronic microscopy, we investigate the influence of initial microstructures on the adiabatic shear behavior of high-strength Ti–5Al–5V–5Mo–3Cr (Ti-5553) alloy with lamellar microstructure and bimodal microstructure. Lamellar alloy tends to form adiabatic shearing band (ASB) at low compression strain, while bimodal alloy is considerably ASB-resistant. Comparing with the initial microstructure of Ti-5553 alloy, we find that the microstructure of the ASB changes dramatically. Adiabatic shear of lamellar Ti-5553 alloy not only results in the formation of recrystallized β nano-grains within the ASB, but also leads to the chemical redistribution of the alloying elements such as Al, V, Cr and Mo. As a result, the alloying elements distribute evenly in the ASB. In contrast, the dramatic adiabatic shear of bimodal alloy might give rise to the complete lamination of the globular primary α grain and the equiaxial prior β grain, which is accompanied by the dynamic recrystallization of α lamellae and β lamellae. As a result, ASB of bimodal alloy is composed of α/β nano-multilayers. Chemical redistribution does not occur in ASB of bimodal alloy. Bimodal Ti-5553 alloy should be a promising candidate for high performance armors with high mass efficiency due to the processes high dynamic flow stress and excellent ASB-resistance.

On the settlement of Ryabinki 2, dating from the late 11th – early 14th centuries, near the town of Yelets (Verkhnedonskoye field Right bank) under the turf compactly lying armor plates, an on-belt tip with a gold application, and baidana rings have been found. Similar armor plates, rectangular, elongated, with the top edge rounded in the form of an arched design, and the opposite edge straight, were in service in the Mongol army. The on-belt tip is typical of the Kamensk stage of the Askiz culture. If the discovery of Mongolian armor is still the only one in the Upper level in the Don region, the stone plates of the Askiz culture and other military equipment associated with it are already known on 9 monuments of this region and have not yet been found outside of it in the South-East of Russia. The appearance of these finds on the monument could have occurred in the middle or third quarter of the 13th century together with the Mongols, whose activity resulted in the revival of trade relations in the Don basin.

Coastal shorelines are a key interface between terrestrial and aquatic ecosystems and are vital for human livelihood. As a result, shorelines have experienced substantial human modifications worldwide. Shoreline “hardening” – the construction of armor including seawalls, bulkheads, or rip-rap – is a common modification that has substantial negative ecological effects. Currently, restoration involving the removal of armor and replacement with “living” shorelines is becoming an established practice. Still, the ecological response to armor removal is oftentimes unpredictable and site-specific. We hypothesized that the confluence of larger-scale geophysical features might strongly influence ecological restoration outcomes at particular locations. To measure the effectiveness of armor removal in the context of broad-scale geophysical features across the Salish Sea, WA, USA, we studied 26 paired restored and natural reference beaches of the same shoretype (feeder bluff, accretion shoreform, or pocket beach), as well as corresponding fetch, sub-basin, and percent of shoreline sediment drift cell armored. Sites were restored for an average of six years. We gauged restoration effectiveness based on levels of five ecological response variables: beach wrack (percent, depth), logs (count, width), sediments (percent sand), vegetation (percent overhanging, count of fallen trees), and insects (density, taxa richness). We found that armor removal often restored these variables to natural levels, but that restoration response was dependent on geophysical features such as shoretype and fetch. Natural beaches did have higher measurements of overhanging vegetation, fallen trees, and insect taxa richness, as these features likely take time to mature at restored beaches. Feeder bluffs had a higher proportion of surface sand and number of fallen trees than other shoretypes, coinciding with the erosion of bluff material, whereas natural pocket beaches within bordering rocky headlands had higher insect densities. Sites with a large fetch had higher input of deposited wrack and logs, whereas sites with a small fetch had higher input from localized terrestrial sources – fallen trees and eroding sand. By incorporating the effectiveness of restoration with landscape features such as shoretype and fetch, we can more effectively plan for future restoration actions and better predict their outcomes.

Copyright of INTRECCI d'Arte is the property of Universita di Bologna, Dipartimento delle Arti visive, performative e mediali, Alma Mater Studiorum 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.)

This is a study to investigate ballistics performance of armor structures with in-layer deflector against projectiles. For this purpose, the armor structure, which consists of a v-cross section sheet metal array covered with aluminum and steel plates, has been designed and optimized. Firstly, numerical simulations were studied using the finite-element method (FEM). The ANSYS LS-DYNA FE software is used for the ballistic analysis. The Johnson-Cook constitutive equation and damage model were used to model the behavior of metal armors under impact in the ballistic simulations. In the next step, experimental studies were carried out. Penetration depths were measured; including the magnitude of plate bending in front of the target plate and bulging behind it. Comparisons between the results of the finite element analysis (FEA) and the tests reveal that a bullet with a velocity of 868 m/s penetrated the target, but the target could not be penetrated at a firing speed of 631 m/s Furthermore the experimental and numerical results were in good agreement. [ABSTRACT FROM AUTHOR]

Recently, large offshore wind power plants have been installed far from the shore, using long HVAC three-core armored cables to export power. Its high capacitance may contribute to the appearance of unwanted phenomena, such as overvoltages or resonances at low frequencies. To adequately assess these problems, detailed and reliable cable models are required to develop time-domain/frequency-domain analyses on this type of cables. This paper presents, for the first time in the literature, an assessment on the performance of 3D finite element method-based (3D-FEM) models for developing frequency-domain analyses on three-core armored cables, confronting simulation results with experimental measurements found in the literature for three real cables. To this aim, a simplified ultra-shortened 3D-FEM model is proposed to reduce the simulation time during frequency sweeps, through which relevant aspects never analyzed before with frequency-domain 3D-FEM simulations are addressed, such as total losses, induced sheath current, magnetic field around the power cable, positive and zero sequence harmonic impedances, as well as resonant frequencies. Also, a time-domain example derived from the frequency-domain analysis is provided. Remarkable results are obtained when comparing computed values and measurements, presenting the simplified ultra-shortened 3D-FEM model as a valuable tool for the frequency-domain analysis of these cables. [ABSTRACT FROM AUTHOR]

Copyright of Studi e Materiali di Storia delle Religioni is the property of Editrice Morcelliana S.p.A. 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.)

Development of lightweight armors is vital in order to provide ballistic protection in a more effective way. The weight of steel armor can be decreased significantly by setting a front ceramic layer on it. In this paper, the influence of utilizing SiC and Al2O3 ceramic front layer on the ballistic behavior of 4140 bainitic steel was investigated experimentally. All steel plates were initially subjected to the austempering treatment by applying the austenitization at 860 °C for 1 h and then holding in a salt bath at 343 °C for 50 min to get fully bainitic microstructure. And then, the laminated composites, consisting of SiC or Al2O3 front layer (50 × 50 mm in size) and bainitic steel backing layer, were prepared by joining these layers with an acrylic adhesive. After the mechanical and microstructural characterization of the bainitic steel, the ballistic shots were made using 7.62 × 51 mm AP projectile with an average speed of 788.4 m/s on both monolithic steel and layered armor samples for comparison. The samples, which stopped the bullet at normal impact condition without complete perforation or disintegration of the bainitic steel layer, were termed as successful. The bainitic steel achieved the ballistic protection at a thickness ≥ 14 mm but the use of SiC layer provided the weight saving of at least 42.9% and the Al2O3 front layer enabled the weight reduction of 28.6% in the armor with respect to the monolithic 4140 bainitic steel. [ABSTRACT FROM AUTHOR]

Traditionally, electromagnetic transient (EMT) programs in the time domain cannot deal with submarine cables buried in the seabed, as available routines demand one medium to be lossless to derive per unit length impedance and admittance matrices. This paper proposes a suitable approach for modeling of HVDC submarine cables, i.e., single-pole, single-core cables with thick armors, in EMT-type programs to allow an accurate representation of the seabed buried cables. The expressions for evaluating pul parameters are based on a quasi-transverse electromagnetic (quasi-TEM) approximation of a full-wave formulation. Two distinct approaches are considered for time-domain modeling. The first one is based on the Method of Characteristics (MoC) and relies on the main structure of the so-called universal line model (ULM), harnessing its implementation in an EMT program. The second approach is based on the rational fitting of the cable nodal admittance matrix using the Folded Line Equivalent (FLE). The time responses of both approaches are compared with the one obtained using the Numerical Laplace Transform (NLT), and an excellent agreement was found. • Rational modeling of propagation parameters (characteristic admittance and propagation function) of a seabed buried HVDC cable, i.e., considering both external media to be lossy. • Rational modeling of a seabed buried HVDC cable using the folded line equivalent. • Evaluation of both approaches for modeling a submarine cable aiming an EMT-based implementation. • Accuracy comparison for a step-like voltage response test considering a practical configuration and evaluating the results against those obtained using the Numerical Laplace Transform. [ABSTRACT FROM AUTHOR]

Introduction. The article deals with the juan (chapter) 42 of the Qing source “Qinding Huangyu Xiyu tuzhi” written in the second half of the 18th century and devoted to the weapons and banners of the Muslim population (Huibu) of the former Dzungar state. The chapter has not been previously translated into European languages and has not been the object of a special study either. The purpose of the research is to examine and introduce this new data for scholarly attention and further inquiry. Results. The compilation of the document was initiated by Emperor Qianlong after the territory of the Dzungar state was annexed to the Qing Empire. A group of Qing officials and of European specialists was sent to explore the newly acquired lands. The work in Dzungaria was largely carried out in 1756–1757, while the study of East Turkestan was completed in the spring of 1759. The work on the text itself began the same year to continue for about 23 years (1759–1782). Manchu military leaders who participated in the war in Central Asia took part in the compilation of the document, too. The chapter under study describes three types of bladed weapons of the Muslim population in the region (kılıç, selem, hançer), spear (naiza), ax (aibalta), bow (yay), arrows (ok), quiver (saadak), chain mail (sauyt), plate armor (kuyak), quilted soft armor (olbog), mirror armor (char-ayna), helmet (duulga), and plate belt (beldemchi). Special attention was given to such parts of military suits as quilted liners of helmets and upper trousers (shalbars). Also, two types of battle banners are described in detail, such a salam, the small banner of beys and tug, a big banner. Each item is supplied with a description and the transcription of its original name. In some cases, the material used for their manufacture and typical sizes are indicated. Conclusions. The data of the written source under study compared with authentic samples of weapons and pertaining visual materials has shown that the Qing officials described the weapons and banners of the region with high degree of reliability. Some of this information is unique and can be found in no other sources of the period. The authors pointed out correlations between the original names of the weapons and armor with their constructive features, which opens new avenues for further research of the written works and epics of the Turkic population of Central Asia.

The crossing of the Suez Canal by the Israel Defense Forces (IDF) during the Yom Kippur War of October 1973 encompassed the toughest and bloodiest battles that the IDF had ever known. Because of the characteristics of the forces and missions involved, it was the ultimate expression of a multi-dimensional battle. During the campaign, there were battles to achieve breakthrough and approach clearing, armor versus armor battles, water obstacle crossings, bridging, establishment of a bridgehead, all featuring complicated logistics. Most of the branches of the IDF became involved and a full range of combat apparatus was deployed, including some items which had not been fully developed and on which training had not been suitably completed. The central problem of the crossing campaign was the "orchestration" of new fighting materials--the means to achieve a water crossing--into a battle that had not been foreseen. Alongside organization, fighting doctrine, and training, this kind of orchestration also demanded innovative leadership and command and control, effective communications, and the ability to cope with a complex and unexpected battlefield. The aim of this article is to test and compare the objectives, planning, and execution of two crossing campaigns--that of the Egyptian Army and that of the IDF. The differences in doctrine stemmed from the choice of strategic objectives and from the adoption of differing combat doctrines. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shanghai Physical Education Institute / Shanghai Tiyu Xueyuan Xuebao is the property of Shanghai Physical Education Institute 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.)

It is important to understand how ballistic materials respond to impact from projectiles such that informed decisions can be made in the design process of protective armour systems. Ballistic testing is a standards-based process where materials are tested to determine whether they meet protection, safety and performance criteria. For the V50 ballistic test, projectiles are fired at different velocities to determine a key design parameter known as the ballistic limit velocity (BLV), the velocity above which projectiles perforate the target. These tests, however, are destructive by nature and as such there can be considerable associated costs, especially when studying complex armour materials and systems. This study proposes a unique solution to the problem using a recent class of machine learning system known as the Generative Adversarial Network (GAN). The GAN can be used to generate new ballistic samples as opposed to performing additional destructive experiments. A GAN network architecture is tested and trained on three different ballistic data sets, and their performance is compared. The trained networks were able to successfully produce ballistic curves with an overall RMSE of between 10 and 20 % and predicted the V50 BLV in each case with an error of less than 5 %. The results demonstrate that it is possible to train generative networks on a limited number of ballistic samples and use the trained network to generate many new samples representative of the data that it was trained on. The paper spotlights the benefits that generative networks can bring to ballistic applications and provides an alternative to expensive testing during the early stages of the design process. [ABSTRACT FROM AUTHOR]