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The goal of this experiment is to investigate the effect of laser engraving parameters on Al 6063 aluminum alloy specimens using a fiber laser engraving equipment. The experimental design makes use of Taguchi's L16 orthogonal array. Surface roughness and engraving depth are the responses which are to be optimum for machining process parameters such as fill spacing, power, frequency, and scan speed. Using regression analysis, the mathematical models for individual responses were created. Grey relational analysis coupled with the Taguchi technique has been presented for simultaneous response optimization. The optimal setting parameters for multiple performance characteristics is fill spacing at level-3, power at level-4, frequency at level-2 and scan speed at level-4 i.e., FS3-P4-F2-SS4. To determine the significance of the models, the Analysis of Variance (ANOVA) approach is used. Finally, in the confirmation test, it is observed that the grey relational grade is improved from the initial process parameter combination.

Due to demands of high strength and light-weight materials such as Al 6063 aluminum alloy in industrial and aerospace application, it is necessary to choose machining operations by which the materials should be less affected. The present work shows how effectively the responses (HAZ, MRR and circularity) of fiber laser engraving (which is a non-traditional machining operation) varied with the input process parameters (power, scan speed, frequency and fill spacing). On the basis of Taguchi’s L16 orthogonal matrix and S/N ratio analysis, the optimum input parameter combinations were found out for each response individually. Finally, the improvement S/N ratio for closeness coefficient index (CCi) of the above responses was determined to be 3.83 dB by using TOPSIS.

A novel flexible capacitive pressure sensor based on hybrid micro-structured (HM) polydimethylsiloxane (PDMS) dielectric layer was developed. The HM-PDMS with M-tooth structured patterns was fabricated using a laser engraved acrylic master mold. The top and bottom electrodes were fabricated by depositing silver (Ag) on flexible polyethylene terephthalate (PET) substrate using additive screen-printing process. The pressure sensor was assembled by sandwiching two HM-PDMS based dielectric layers between the top and bottom electrodes. The capability of the developed pressure sensor to detect a wide range of pressure was investigated by applying varying pressure from 0 to 1 kPa, 1 to 10 kPa, and 10 kPa to 40 kPa. A sensitivity of 51.36% kPa-1, 8.37% kPa-1, and 2.46% kPa-1 was obtained for the pressure ranges of 0 to 1 kPa, 1 to 10 kPa, and 10 to 40 kPa, respectively. The capacitive pressure sensor response, hysteresis, and repeatability of the fabricated pressure sensor is investigated and presented in this paper. To demonstrate the wide sensing range of the pressure sensor, the sensor was attached to face mask for breath monitoring applications that require low pressure sensing of ~20 Pa, and to the hand glove for fingertip pressure monitoring applications that require relatively high pressure sensing of ~3 kPa.

Organic acids are important components in determining fruit taste, and it is necessary to develop rapid analysis methods for them. A simple and effective method based on laser-engraved free-standing terahertz (THz) metamaterials has been developed for rapid analysis of fruit acids. Compared with traditional fabrication methods for THz metamaterials, laser direct writing technology was employed for fabricating the Cu-foil-based THz devices in this research, which is time-saving, cost-effective, and high-throughput. To realize effective fabrication of metamaterials, proper fabrication parameters were selected according to morphology and spectral characterization. Numerical analysis was performed to reveal the fundamental mechanism of THz sensing based on metamaterials. Furthermore, experimental results indicate that fruit acid with a concentration of 0.1 mg L−1 can be successfully distinguished, which is quick and simple compared with traditional acid–base titration. The proposed strategy demonstrates great potential for rapid in situ analysis of flavor components in food products.

Spark-assisted chemical engraving (SACE) is suitable to machine hard and brittle insulating materials such as quartz glass; however, the processing efficiency is quite low for achieving good machin...

The demand inherent to the aeronautical industry in terms of productivity and quality requirements leads to develop new cutting tools. Hence, PCD tools meet the requirements in productivity while machining low machinability aeronautical alloys such as Ti6Al4V. Tool chipbreakers play a considerable role in terms of tool life. However, due to the extreme conditions (temperature and pressure) required to manufacture PCD tools, any complex geometry on tool rake faces is not viable, so chipbreakers are not possible, except for those external to inserts. This work proposes a groove-type laser engraved chipbreaker design and a manufacturing methodology, with experimental validation on turning a Ti6Al4V workpiece. The so-manufactured chipbreakers achieve titanium alloy chip fragmentation, making easy chip removal from the cutting zone. A set of experiments involving various laser parameters to characterize the PCD depth and surface integrity and experimental validation for those chipbreakers designs were carried out in finishing cutting conditions. The optimum parameters for the engraving of PCD were found, obtaining satisfactory breakage of titanium chips. Chip length was always below 17.29 mm. Authors are grateful to Basque government group IT IT1337- 19, the Ministry of Mineco REF DPI2016-74845-R and PID2019- 109340RB-I00, and the UPV/EHU itself for the financial aid for the pre-doctoral grants PIF 19/96.

Spark Assisted Chemical Engraving (SACE) is a micro-machining technology for non-conductive materials, mainly glass, based on thermal assisted etching. Generally, during SACE, drilling proceeds at a fast rate reaching 100 µm/s for the first 100 µm and then it slows down for depths higher than 300 µm. While several techniques have been proposed to establish faster drilling, they mainly rely on tuning the machining parameters to enhance the machining performance. However, with this approach machining parameters need to be constantly tuned to achieve certain machining performance depending on the size of the tool and the features needed. Therefore, this necessitates further work to enhance understanding regarding the SACE machining process fundamentals in order to enhance machining speed and quality. Since SACE is a thermal assisted etching process, both local heating and flushing of electrolyte in the machining zone are required. However, to the authors’ knowledge there is not any study that attempts to analyze the effect of each of these machining limiting factors on the machining performance. This work attempts to clarify the effect of each flushing and heating on the drilling progress for hole depths higher than 100 microns. It therefore provides a deeper understanding of the fundamentals of the SACE machining process.

Laser-engraved graphene (LEG) has been applied increasingly in flexible electronics over the past decade owing to its unique physical and chemical properties, and has shown great promise in energy controls, chemical and physical sensing, and telemedicine. In situ laser engraving has empowered graphene with additional versatilities such as miniaturized patterning, tunable composition, controllable morphology, and environmental friendliness. In this review, the technological advances of LEG from synthesis to applications in flexible and wearable electronic devices are summarized. Specifically, the use of LEG in designing next-generation nanogenerators, batteries, supercapacitors, physical sensors, gas sensors, biosensors, and wearable/telemedicine systems is discussed. An outlook related to LEG-based flexible electronics and key technological bottlenecks is identified.

Newly discovered and previously documented Late Neolithic chalk plaques from the Stonehenge locality have been subjected to new, non-invasive techniques which allow access to previously unseen elements of archaeological evidence. The application of these methods – involving Reflectance Transformation Imaging (RTI) and Polynomial Texture Mapping (PTM) – has revealed detail of the surface preparation and allowed methods and sequence of the compositions to be unpicked, clarifying their complexities. The results reveal a range of approaches to the compositions, some of which demonstrate planning, order, and intention while others include less systematic, rapidly executed sketches. Investigations of lines and surfaces have been made, supplemented by preliminary studies of replicated test pieces, to examine potential implements used in their creation and remark on plaque biographies and surface attrition following manufacture. Furthermore, detail revealed by RTI provides indications of the orientations in which some of the plaques should be viewed and – in one instance – suggests a ‘reflected’ element that may not be entirely abstract. Results from improved radiocarbon determinations place the plaques in the early part of the 3rd millennium bc which, together with identification of individual motifs, allows the plaques and the designs to be reconsidered within the corpus of Neolithic art in the British Isles.

Experimental animation is developping in festivals, demonstrations and exhibitions and it is closely joined to the graphic, pictorical, musical and photographical productions. Definitively it is used as artistic expression medium. Therefore we should see animation as a new support of broadcasting the work, according to the new ways of seeing and understanding the world and the needs of the society. Analyzing this new support we discover that the techniques employed are so different and diverse like the artists self that use them, finding between them techniques like painting or engraving, both possessors of a wide range of procedures and outcomes.Focussing our attention on engraving, we discover that, for a group of experimental animators, this is the base for their produccions. Some of them influenced by the pioneers Len Lye en Norman McLaren, use the technique in its purest essence, some others use their aesthetics and characteristics as a starting point in order to develop their productions along with other techniques.Engraving offers the possibility of working with different techniques attending to his mould and printing, considering the technical procedures, the printing methodes and the manipulation and intervention of the printings as a wide range of new possibilities.

Laser processing results in modified mechanical properties and microstructural evolution due to high temperatures and fast cooling rates. Different laser surface treatment techniques are under investigation for their potential to alter local microstructure and properties while maintaining properties of the bulk material. Fatigue life of laser-engraved powder metallurgy steel is shown to be significantly reduced compared to as-sintered material, suggesting a degree of microstructural modification with engraving. The misorientation, dislocation density, and phase of samples engraved with a 2D matrix pattern using one laser pass and five laser passes are characterized using optical microscopy and SEM-EBSD, and a CFD simulation of the laser process quantifies the temperature profile of each laser engraving. Deep-engraved samples are seen to result in a possible martensitic transformation at the surface of the engraved region because of increased time at elevated temperature and extreme cooling rates. These findings reinforce the importance of understanding microstructural evolution during precision tailoring via laser surface modification.

В статье раскрываются репрезентативные формы образа советской женщины на материалах нестоличного города. Возможность привлечения сведений радиопередач и эго-документов как малоизученных форм женской репрезентации позволяет автору выявить и сравнить идеализированный и реально существующий образ советской женщины 1950–1960-х годов. Средства массовой информации формировали идеологически одобренный женский портрет, являясь транслятором допустимых и запрещенных норм, которые жительницы города старались соблюдать. Превалирующий образ «женщины-работницы», активно вовлеченной в семейную и общественную жизнь, был недосягаем для «обычных» советских женщин. Несмотря на это, многие из них стремились занять лидирующие позиции хотя бы в одной из сфер. Несовпадение идеализированного и реально существующего женских образов влекло за собой критику со стороны власти и общественности. Опасение быть осужденной и желание обличать накладывали на женщин определенные каноны поведения, которые исподволь внедрялись массовой культурой. The article investigates the image of a Soviet woman as portrayed by provincial mass media. The article analyzes such underrated sources of reliable information as egodocuments and radio performances, which enables the author to compare the idealized image of a Soviet woman and the real image of a Soviet woman of the 1950s–1960s. Mass media created an ideologically “proper” image of a female worker who was actively involved in family and social life. Despite the fact that many “ordinary” Soviet women did their best to fully realize their potential in at least one sphere of life, they had no means to conform to the ideal image broadcast by the media. Due to the discrepancy between the ideal and realistic images, Soviet women often fell victim to social and political criticism. Gnawed by the fear of censure and the desire to condemn others, women were forced to acquire certain behavior patterns dictated by mass culture.

Recent increasing interest in light guide plates (LGPs) based on the advanced manufacturing towards optoelectronics applications has emerged as a potential technology. The aim of this study was to estimate the optical characteristics on practical verification of laser-engraved glass light guide plate with concave microstructures. The case study can use the industrial ability of picosecond laser (pico-laser) technique, a type of ultrafast laser pulses, to directly engrave a glass sheet (Corning Iris® Glass) with functional concave microstructures for fabricating an LGP. Eight small pieces of samples with array of microstructures engraved on different processing conditions were made for measuring optical characteristics before and after the samples were etched by hydrofluoric acid. Here, the engraved 6-inch LGP structures can make light exit from the LGP uniformly. Additionally, the two optimized LGPs were put in a 7.8-inch backlight module where the measured results showed the uniformity of spatial luminance was 0.9. The study demonstrated the one-step process utilizing pico-laser technique, yielding for the design of microstructures of thinner large-sized liquid crystal display (LCD) products in the manufacturing of LGPs for lighted-up in a backlight unit (BLU).

Manufacturing of Y-branch coupler depends on high technology production equipment and in-factory accuracy assembly tools. The manufacturing of a 1×2 Y-branch symmetric and asymmetric waveguide coupler based on the mould replication process and Epoxy OG142 as an optical core is presented; an alternative to provide a less complex technique. The polymer optical waveguide adopted two basic designs: the 1×2 Y-branch symmetric coupler as the core structure and the 1×2 asymmetric coupler that allows non-symmetric optical splitting. This paper focused on the main structure fabrication of the 1×2 symmetric and asymmetric waveguide coupler that produces a power output. The fabrication was done by engraving acrylic to produce a master mould using CNC machining tools for optical devices. Both 1×2 devices were made via soft lithography, which duplicated the pattern from the master mould onto a second mould to produce an actual device. Optical polymer epoxy OG142 was injected into the second mould, of which the product was then put on top of acrylic. The device was completed after curing the optical polymer glue, epoxy OG142, by exposing the assembly on the second mould under UV light until both parts bonded. The difference between the simulation and design TOFR value was only ±2%. This showed that the simulation and design are in good agreement, which provides similar performance.

Distinctive, dark-coloured, glaze-like mineral accretions are common on low-angle surfaces in sandstone rock shelters in the Kimberley region of north-western Australia, where they provide an attractive medium for the production of deep engravings, and occasionally, are associated with painted rock art. These accretions form within the shelter dripline and are similar to those reported from other sites around the world, where they have been used for radiocarbon dating of associated rock art. This study uses extensive field observations and mineralogical analysis of 77 such oxalate-rich accretions collected at 41 different sites across a wide area of the north Kimberley region. The mineralogy of these accretions is dominated by well-crystallised calcium oxalate and sulphate minerals, most commonly whewellite and gypsum, with significant occurrences of phosphates in some samples. The accretions are typically several millimetres thick and characterised by distinctive internal laminations that show regular stacked undulations, giving a stromatolitic appearance under the microscope. Together with other apparently microbial features observed under the scanning electron microscope, these features provide strong support for a microbiological origin for these oxalate-rich accretions. The well-crystallised nature of the oxalates and the preservation of fine laminar features within the accretions supports their use for radiocarbon dating.

An approach which allows both electrochemical studies and surface enhanced infrared characterization of electrodeposited Cytochrome C is presented. This approach is based on in-plane disordered arrays of resonant slits engraved in Au substrates using focused ion beam. For light-polarized perpendicular to the slit, the reflectivity spectra of the slit arrays show dips related to the excitation of the slit plasmon resonance, whose position depends on the slit length. Due to the presence of the continuous Au layer around the slits, the very same substrates can be used to perform electrochemical studies. By varying the slit length, we have tuned the plasmon resonance to match the absorption bands of electrodeposited Cytochrome C, demonstrating the detection of minute amounts of this protein, all the way down to a single monolayer., Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. We acknowledge financial support from MINECO through projects AMES (MAT 2014–58860-P), Quantum Spin Plasmonics (FIS2015−72035−EXP), MIRRAS (MAT2017−84009−R), and Comunidad de Madrid through project SINOXPHOS−CM (S2018/BAA-4403). We acknowledge the service from the MiNa Laboratory at IMN and funding from MINECO under project CSIC13−4E−1794 and from CM under project S2013/ICE−2822 (Space−Tec), both with support from EU (FEDER, FSE).

Pulsed lasers were used to drill small holes distributed homogeneously on buffer layers of coated conductors, aiming at improving their mechanical properties. Each hole should be engraved by only one pulse of laser for practicality. The effect of pulsed laser engraving on buffer layers, CeO2 in this study, were investigated. The size and depth of the hole can be controlled by adjusting laser parameters. ${\rm{REB}}{{\rm{a}}_{2}}{\rm{C}}{{\rm{u}}_{3}}{{\rm{O}}_{\rm{y}}}$ (REBCO) layers were then grown on the laser patterned buffer. The growth mechanism of REBCO above the drilled holes was studied. In addition, influence of drilled holes on the critical currents of coated conductors were studied. Finally, the effect on mechanical strength of as grown samples were studied by measuring their delamination strength under transverse tension.

This article deals with engravings depicting some­ times life­sized Bronze Age metal objects from “closed” burial contexts and “open­air” sites in northern Europe. These rock art images have mainly been used for comparative dating with the purpose of establishing rock art chronologies, or interpreted as a poor man’s” substitute for real ob­ jects that were sacrificed to immaterial gods and goddesses. In this article, these rock art images are pictured from a perspective that highlights the mu­ tual cultural biography of humans and objects. It is argued that the rare engravings of bronze ob­ jects at scale 1:1 are best explained as famous ani­ mated objects that could act as secondary agents, which sometimes allowed them to be depicted and remembered. Moreover, two different social set­ tings are distinguished for such memory practice: maritime nodes or third spaces where Bronze Age Argonauts met before, during or after their jour­ neys, e.g. places where novel technological and/or famous objects entered and re­entered the social realms, and burial contexts where animated objects sometimes was buried at the end of their life­course

In roll-to-roll continuous printing, given the limitations in the pattern engraving technique and the need for accurate contact angle control between the ink and substrate, printing fine lines in the 10-μm scale is a major hurdle that needs to be addressed to achieve mass production of printed electronic devices. To address this issue, we propose a novel printing method based on gradation engraving; this method allows for both greater control over the width decrement of printed patterns as well as narrower fine lines than those achieved using an engraved pattern in the printing roll. Our experimental results show that, using the proposed method, printed line widths could be decreased according to the curvature of the sidewall of the engraved cell, even in the same aspect ratio. Furthermore, the width of the printed pattern was decreased by up to 62%, as compared to that achieved via the engraved cell, and a fine printed line narrower than 10-μm could be achieved. The proposed method represents a suitable alternative for the fabrication of 10-μm, or even thinner, fine conductive lines via the roll-to-roll continuous printing process.

Hydrogen generated by electrochemical water splitting is an attractive alternative to fossil fuels. Herein, we developed hollow-like Co2N nanoarrays that serve as electrocatalysts for the hydrogen evolution reaction (HER) with surface engineering by argon plasma. The argon plasma-engraved Co2N nanoarrays (Ar-Co2N/CC) represent a dramatic catalytic performance for the HER with an overpotential of 34 mV at a current density of 10 mA cm-2 in an alkaline electrolyte, as well as outstanding durability of 240 h. Characterization experiments and density functional theory (DFT) calculations suggest that the enhanced HER activity is due to the rational coordination environment of Co, which can be tuned by Ar plasma engraving. Based on our research, one new view for conducting exceptional catalyst surface modification engineering via plasma engraving might be established.

Raman spectroscopy has been applied to check if there are detectible material differences beneath the inscribed and non-inscribed areas of marble-based written artefacts, which could be further used to visualize lost or hardly readable text via suitable mapping. As a case study, marble segments with ∼ 2000-year-old inscribed letters from Asia Minor (western Turkey) and marble gravestones with 66 ± 14-year-old inscriptions from the cemetery of Ohlsdorf (Hamburg, Germany) have been subjected to Raman spectroscopy, as well as to complementary X-ray diffraction, wavelength-dispersive electron probe microanalysis, and Fourier-transform infrared spectroscopy, to thoroughly study the effect of different environmental conditions, grain size, and inscription age on the nature and penetration depth of marble alteration. The results demonstrate that environmental conditions rule over the type of dominant weathering changes, which are carotenoid molecular inclusions produced by lichen and amorphous carbon for marbles from Hamburg and Asia Minor, respectively. The alteration is much stronger in medium- and coarse-grained than in fine-grained marble, but it is suppressed by letter colouring. In the absence of letter colouring, the weathering-related products in both ancient and modern engraved marbles are more abundant beneath than away from the engraved areas, and the penetration depth is larger due to the enhancement of fissures and micro-cracks around the inscribed areas. We show that the Raman intensity ratio between the strongest peak of the weathering-related product (ν(C=C) ∼ 1520 cm−1 for carotenoids or the G peak ∼ 1595 cm−1 for soot-like carbon) and the strongest peak of marble (CO3 stretching near 1087 cm−1) can serve as a quantitative marker to indirectly map the lateral distribution of cracks induced during the inscribing process and hence can potentially be used to trace lost text on vanished marble inscriptions. This approach can be applied to other rock types, but further studies are required to identify the corresponding autochthonous weathering-related products.

In this letter, a dielectric resonator antenna (DRA) with an engraved groove and a comb-like metal wall for beamwidth enhancement in both E- and H-planes is proposed. First, with an engraved groove, the radiation intensity on the top wall of the rectangular DRA can be enhanced, which significantly broadens the half-power beamwidth (HPBW) in the E-plane. Second, by placing a regular notched metal wall around the grooved DRA, HPBWs in both E- and H-planes can be greatly widened simultaneously. Finally, for the further improvement of HPBW in the H-plane, the regular notched wall is replaced by a 3-D printed comb-like metal wall. Vertical currents can be induced on the comb-like wall due to the coupling of the DRA, which can increase gain at low elevation angles and further enhance HPBW of 20°. Thus, HPBWs of the proposed antenna in both cutting planes can be improved step by step without scarifying each other and bandwidth. To verify the proposed design, an antenna prototype is fabricated and measured, which shows an impedance bandwidth of 38.2% (2.58–3.8 GHz), with excellent HPBW performance of 248° and 148° in the E- and H-planes, respectively.

Architecture and visual arts in general have been subjects of a growing body of recent scholarship connected with the ecclesiastical history of the ‘Long Eighteenth Century’, but little attention has been given to portraiture. Although honourable mention should be made of pioneering work by John Ingamells on painted episcopal portraits, and by Peter Forsaith, very recently, on Methodist portrait prints, other aspects of this extensive subject still await investigation. The article outlines the development of engraved portrayal of clergy, mainly of the Church of England, during the two centuries before production of multiple images was taken over by photography, and indicates how the quantity, variety, and dissemination of such material can provide some index of the priorities of a pre-photographic age. It does not aim to be a comprehensive or a complete survey of the corpus of engraved portraiture; nevertheless, this article provides an initial guide to the abundance of previously unexplored illustrative material, and may suggest a framework for further exploration. It is hoped that future scholars will build on this initial work to enable a complete catalogue of such images to be developed and further explored.

Objective Micro-nano scale surface modification of Ti-6Al-4V was investigated through the fascinated modern fiber engraving laser method. The process was performed at a high laser speed of 2000 mm/s, under different laser frequencies (20–160 kHz) and groove distances (0.5–50 μm). Methods Topographic evaluations such as Atomic Force Microscopy (AFM) and Field Emission Scanning Electron Microscopy (FE-SEM) were used to identify the quality and regularity of patterns. The proliferation of human osteoblast-like osteosarcoma cells (MG63) was analyzed by MTT assay for up to 72 h. Also, the plate counting method was used to quantify the viability potential of the modified surface against Escherichia coli bacteria. Results The cellular viability of the sample modified at the laser frequency of 20 kHz and grooving distance of 50 μm increased up to 35 and 10% compared to the non-treated and control samples, respectively. In the case of the surface modification at lower grooving distances range between 0.5–50 μm, the maximum laser frequency (160 kHz) applied leads to lower pulse’s energies and less bacterial adhesion. Otherwise, at groove distances more than 50 μm, the minimum laser frequency (20 kHz) applied reduces the laser pulse overlaps, increases the cell adhesion and antibacterial properties. Significance Surface modification by the fiber engraving laser process significantly enhances the cell adhesion on the surface. As a result of such roughness and cell adhesion enhancement, the surface toxicity feature diminished, and its antibacterial properties improved.

A three-coordinate impact-engraving machine in a computer-copying system is considered. Its errors are evaluated, and remedies are proposed. Kinematic equations for zigzag motion of the impact tool are derived. The dynamics of a controllable vibrational generator in regular machine-tool operation is investigated.

The CNC machining of nephrite is increasingly used in the jade engraving industry. As the most important standard for quality evaluation, surface roughness is influenced by cutting parameters. In this paper, taking the Buddha head as the machining object, the influence of cutting parameters on the surface quality of was studied by SYIL S7 CNC milling machine. The grooving experiment was carried out at spindle speed of 24,000 rpm, then the CAXA manufacturing engineer and JDpiant software were comparatively applied in machining. Furtherly, the influence of the spindle speed on the roughness was investigated. The research results were summarized as follows: (1) No edge breakage appeared when feed speed lower than 300 mm/min with the maximum depth of cut of 0.1 mm. In this case, when the jade is machined with the spindle speed range of 16,000–24,000 rpm, the mean roughness Ra was in the range of 1,496.111–891.842 nm. (2) JDpiant software is more suitable for CNC jade engraving than CAXA manufacturing engineer. (3) In roughing stage, only the high-speed grinding contdition is satisfied, the integrity of side profile could be guaranteed. The higher spindle speed was conducive to achieve the fine surface quality. (4) The tungsten steel cutter in finish machining stage shows better grinding ability than diamond cutter used in rough machining stage. In order to formulate an economic spindle speed, the finishing surface roughness should be considered in conjunction with the requirement of polishing.

The museums of Uzbekistan keep several wooden printing blocks that were used for printing on textiles in the 13th H./19th G. century and the early 14th/ 20th G. century. They are an important aspect of manufacturing wooden artifacts because of having many specialized centers in the wood craft in Central Asia, especially in Bukhara, Samarkand, Tashkent,Khokand,Khiva and other areas. These printing blocks have different shapes, sizes, types and designs. They are decorated with many decorative elements, including floral motifs, geometric shapes, and architectural elements. Moreover, they help identify the wood industry in Central Asia at the time, in terms of technique, decoration method, engraving, and decorations. The present study aims to highlight the models of these wooden printing blocks, such as their forms, types, raw material, technique of manufacturing and decoration, decorative elements, and designs. The results may help the researchers of applied arts in Central Asia.

Laser deep engraving is one of the most promising technologies to be used in wood engraving operations. In this method, a laser beam is used to ablate a solid wood bulk, following predetermined patterns. The sculpture is obtained by repeating this process on each successive thin layer. The degree of precision of the shape, the removal rate, and the surface quality during the engraving process strictly depends on the materials properties, the laser source characteristics, and the laser parameters. This work investigates the influence of the process parameters on the material removal rates by engraving redwood using a co2 laser working with a wavelength λ = 10.6 µm. The examined parameters were: the laser power, the scanning speed, and line overlapping space; each of them has a different value (20, 25, 30, 35, and 40 W), (100, 300, 500, 700, 1000 mm min−1) and (0.03, 0.06, 0.1, 0.2, 0.3 mm) respectively. The working parameters were designed using the L25 Taguchi methodology for the design of the experiment. Experimental results showed that the co2 laser could successfully engrave the redwood, obtaining different engraving depths. The maximum and minimum depth obtained was 4.25 mm and 0.01 mm. the results show that the engraving depth interaction changes depending on the laser parameters.

The milling of hard materials with a complex shape using conventional methods causes many tool based problems. However, a laser assisted milling process eliminates the tool-based problem because of the small, high intensity beam used. Laser engraving, which is one of milling methods, is an effective process for the machining of difficult to machine geometries and materials like hot work tool steels. This study focuses on recast layer formation and subsurface hardness as a function of distance. Power, scan speed and frequency were employed for the investigation. The highest hardness was detected at 201 HV, which measured at 800 mm s(-1) for scan speed and 40 kHz for frequency. XRD analysis showed that two different phases, Fe and Fe2.96Si0.05O4, existed on the machined surfaces.

A novel mechanically tunable frequency selective surface (FSS) based on a sliding 3D-printed inserted dielectric is presented in this paper. This paper first introduces the working mechanism of the tunable FSS, which indicates that the variable capacitance is the key to tunability. Based on this, we design an all-metal bandpass FSS with a certain thickness and a matching cross-shaped inserted dielectric. By changing the insertion depth of the dielectric, the resonance frequency can be adjusted. To optimize the performance, an improved structure based on a hollow support and a tripole slot is proposed. A tunable range from 3.24 to 5.52 GHz (53%) and good angular stability is obtained in the simulation. To verify this idea, we fabricate a cross slot prototype by 3D printing and mechanical engraving. Measured results show that this prototype has a continuous tunable range of 3.61 to 5.89 GHz (34.4%).

This paper deals with an important text written by Al-Tīfashāi (580-651 AH/1184-1253 AD) in his famous book “Aʾzhar al-aʾfkar fī gawaḥīr al-aʾhgar” (=The flowers of thoughts about precious stones). Al-Tīfashāi describes a distinguished method of engraving inscription on coral stone rings by “kḥall Qamr haziq” which means the Glacial acetic acid (CH3COOH). This organic acid is suitable for engraving inscriptions on the surface of coral stone rings. The author interprets Al-Tīfashāi's text following his practical steps, tools, materials used, and the suitable duration for engraving inscription on coral stone rings using this organic acid. From the archaeological point of view, dating the first application of this method on coral button rings “seals” is crucial. The author endeavours to date the coral button rings preserved in the Islamic Art Museum of Cairo, and to prove that this organic acid was the engraving method for the inscriptions. The author proved that engraving inscriptions with organic acid had been applied before using sulphuric acid H2 SO4. Finding out this method of engraving inscriptions by an organic acid. Dating its application during the early Islamic period presents a new scientific contribution to methods of engraving inscriptions (normal or inverted) on archaeological Islamic objects.

This paper explores the transient mechanics mechanism of the projectile with double rotating bands engraving into the rifle and the propellant gas pressure distribution law during the rotating band engraving process. Previous studies usually ignored the coupling of projectile, artillery, and gunpowder parameters during the engraving process. To end this, taking a large-caliber artillery system as the research object, a projectile-barrel-charge coupled finite element model is established based on the two-phase flow interior ballistic theory and the finite element method, followed by numerical simulation. Through the comparison with experimental results, such a modeling method is proved to be effective.

Laser engraving is an essential tool of automatic drawings and 3D printers. When the laser engraving tasks become large and complicated, engraving process will be time-consuming. To improve the time and energy efficiency, the trajectory optimization of laser engraving is studied. The trajectory of laser engraving robot is modelled as a large-scale traveling salesman problem (TSP), by converting grayscale images into halftone images. To solve the large-scale TSP, two-layered ant colony system (ACS) is newly proposed to combine k-means, top-layer ACS, and bottom-layer ACS. Finally, we use the presented algorithm to optimize the path of four engraving instances which include tens of thousands of discrete points. Experimental results show that this method can reduce laser engraving time by about 50% compared with traditional engraving methods.

This article examines the engravings of the Beldibi Rock Shelter using digital techniques. The engravings, which consist of a jumping deer and an ox with its head turned back, were first discovered by E. Bostancı in 1959. Both Bostancı and Anati compared them to Western European Upper Palaeolithic figures. If the engravings of Beldibi really exist, they would exhibit the earliest rock art in Anatolia.

Determining the quality of reproduction obtained by direct laser engraving (DLE — Direct Laser Engraving) engravings of the intaglio printing plates and its dependence on the designed profile parameters is an urgent task that will improve the processing of DLE forms and expand its use in the production of securities. Research by optical metallography of engraved strokes of thirty types, which are different in the designed profile (depth (20‒100 μm), width (30‒100 μm), angle of inclination of the walls of the stroke (600‒900)) and the laser’s engraving power, showed that all the engraved strokes of the sample have significant deviations from the specified geometric profile and are usually asymmetric. Since the condition of the surface of the strokes is another additional factor in ensuring the wear resistance of DLE + PVD forms, to take into account this parameter, the principles of scoring the surface of the strokes were developed based on comparison with the sample on a 5-point scale. Experimental studies have shown that, despite the significant differences between the profile obtained by engraving and designed, in terms of possible tactility of prints (the most important parameter of intaglio printing), the vast majority of manufacturing modes and profiles provide a fairly high match of strokes width between engraved strokes and designed ones (80‒130 %). The depth of the stroke varies significantly — from 60 % of the projected to almost 200 %. Due to the significant deviation of the profile from the projected area of intersection of the strokes is in the range of 40‒90 % of the projected. The best geometric parameters have small rectangular strokes. From the point of view of reproduction of a geometrical form of strokes, the trapezoidal profiles have the best parameters. In terms of surface quality of strokes — rectangular profiles. Reducing the radiation power allows both to ensure better reproduction of the geometric parameters of the stroke, and to ensure a better stroke surface quality. The latter is a particularly important factor in ensuring the proper level of adhesion of the protective coating to the brass base, i.e. in the future — higher run-length resistance. Thus, the condition of the surface of the strokes is another additional factor in ensuring the wear resistance of DLE + PVD forms.

Advances in manufacturing technology in the creative industries began to leave the dominance of the role of humans into automated systems to produce high-quality products. CNC laser machine is a computer-programmed machine used to make a product by cutting, scraping, and engraving. In general, people think that CNC machines are expensive goods. The purpose of this study was to design a prototype diode type CNC laser machine for the manufacture of creative acrylic material products. The research method uses the stages of designing, manufacturing, and testing the performance of a diode type CNC laser machine. The CNC laser machine is designed as cheaply as possible by minimizing self-made components and using standard components such as machine frames using aluminum extrusion, laser using a 5500 mWatt laser diode type, stepper motor as an X, Y, and Z axis. Control software is used by USB CNC controller . CAD software is used by Aspire Vectric and CAM software is used GRBL with Adruino Nano microprocessors. The results of a Diode Laser CNC machine prototype with dimensions of 450 × 400 × 300 (mm); work area dimensions 300 × 200 × 35; engine weight 5 (kg). The ability to cut a diode Laser of 5.5 watt CNC machine on black acrylic 3 (mm) with an average time of 0.5 mm/s is the best result. Diode Laser CNC Machine engraving capability of clear acrylic material with dark color paper cover machining time 10 (mm / s).

The principle of operation and functional-kinematic diagram of a three-coordinate impact-engraving machine tool of a computer-copying system are considered. The errors of the machine tool are analyzed, the ways of their elimination are suggested. Kinematic equations of motion of an impactor tool along a zigzag trajectory are derived. The dynamics of a controlled vibration generator is investigated in the mode of standard setting of the machine tool. Keywords: impact-engraving machine tool, integrated computer-copying system, Ae-product, pixel image, functional-kinematic diagram, stepper motor, kinematic trajectory, vibration generation. pupkov@iu1bmstu.ru

Efficiency of coin manufacturing is often limited by the service life of the stamping dies, whose degradation by wear results in decreasing the quality of the produced coin engraving. The aim of this work is to explore the ability of the combined application of experimental characterization and numerical simulation of the material elastoplastic forming response, friction effects, and die material wear rate as a tool to contribute to the coin design in order to ultimately increase the number of coins that can be die forged before the use of a worn die compromises the desired quality of the final product. The following aspects have been particularly addressed in this study. First, the influence of two design parameters related with the quality of the coins, i.e., die displacement and depth of engraving, is quantified determining that the die displacement is the most preponderant since the stamping force needed in this process is higher compared with that obtained by varying the depth of engraving. In addition, it is found that the curvature of the coin relief determines the local stress distribution, in some cases even at the opposite die, resulting in a heterogeneous wear evolution. A complementary wear test reveals that, for the involved range of curvatures, the wear mechanism may shift from dominated by plowing/cutting to dominated by fatigue. It is concluded that the numerical simulation allows considering efficiency of the coining process already at the stage of the aesthetic design of a coin.

A ceramic vessel found at a Mill Creek culture (eastern Initial Middle Missouri variant) site in northwest Iowa exhibits features characteristic of both the Southern Caddo Holly Fine Engraved type ...

When cells are cultured in a Petri dish, the adherent cells attach to the bottom of the dish; whereas, the nonadherent cells float in the culture medium. It was observed that nonadherent cells could be induced to adherent-like cells when cultured in an engraved plastic dish (biosimulator). The adherence of these cells to the engraved surface could be prevented with inhibitors specific for adhesion. It was also observed that culturing microorganisms of the environment in a biosimulator induced weak adhesion and high proliferation. Analysis of the microbiome using 16S rRNA profiling demonstrated that the biosimulator was more efficient in inducing proliferation of several phyla of microorganisms compared with culture by conventional techniques.

A novel capacitive pressure sensor based on micro-structured polydimethylsiloxane (PDMS) dielectric layer was developed for wearable E-skin and touch sensing applications. The pressure sensor was fabricated on a flexible polyethylene terephthalate (PET) substrate, using PDMS and silver (Ag) as the dielectric and electrode layers, respectively. A set of PDMS films with pyramid shaped micro-structures were fabricated using a laser engraved acrylic mold. The electrodes (top and bottom) were fabricated by depositing Ag on PET films using additive screen-printing process. The pressure sensor was assembled by attaching the top and bottom Ag electrodes to the smooth side of pyramid shaped micro-structured PDMS (PM-PDMS) films. The top PM-PDMS was then placed on the bottom PM-PDMS. The capability of the fabricated pressure sensor was investigated by subjecting the sensor to pressures ranging from 0 to 10 kPa. A sensitivity of 0.221% Pa $^{\mathbf {-1}}$ , 0.033% Pa $^{\mathbf {-1}}$ and 0.011% Pa $^{\mathbf {-1}}$ along with a correlation coefficient of 0.9536, 0.9586 and 0.9826 was obtained for the pressure sensor in the pressure range of 0 Pa to 100 Pa, 100 Pa to 1000 Pa, and 1 kPa to 10 kPa, respectively. The pressure sensor also possesses a fast response time of 50 ms, low hysteresis of 0.7%, recovery time of 150 ms and excellent cycling stability over 1000 cycles. The results demonstrated the efficient detection of pressure generated from various activities such as hand gesture and carotid pulse measurement. The PM-PDMS based pressure sensor offers a simple and cost-effective approach to monitor pressure in E-skin applications.