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Traditional embossing processes applied to papers generate significant amounts of heat, leading to the degradation and decreased efficiency of the rubber cylinder, a critical component of the machine, over time. This study investigates a novel internal cooling system designed to address this issue and extend the lifespan of the rubber cylinder. Experiments were conducted using tap water and ethylene glycol aqueous solution as coolants at a machine speed of 350 m/min and a specified pattern density. The results suggests that the non-cooled cylinder started to deteriorate at a surface temperature of approximately 46 °C. However, with the implemented cooling system, the surface temperature was effectively maintained at 4-5 °C below this threshold, significantly extending the operational life of the rubber cylinder. Therefore, this study emphasizes the effectiveness of internal cooling in mitigating heat-induced damage and extending the lifespan of embossing cylinders. [ABSTRACT FROM AUTHOR]

The growing applications and constant miniaturization of electronic devices and of low‐temperature co‐fired ceramics (LTCC) in various fields, such as aviation, telecommunications, automotive, satellite communications, and military, have led to an increase in the demand for LTCC. Such prospects arise due to the continuous scaling down of components and high‐density interconnection in electronics packaging. This paper reports a technique for the transfer of high‐resolution microstructures from silicon substrates to LTCC. In this method, gold and copper patterns were formed by photolithography, electrodeposition, and residual layer stripping on silicon substrate. Lithography provides the opportunity to create and transfer complex patterns for use in several different applications and electroplating enables the use of pure metal for excellent electrical properties. The developed structures were transferred onto a top layer of LTCC tape using hot embossing. Then, the subsequent layers were stacked, laminated, and sintered. A resolution of 1.5 μm after free sintering and 4.5 μm after pressure‐assisted sintering was achieved. This distinctive method can be useful for several applications requiring high‐resolution and superior electrical properties. [ABSTRACT FROM AUTHOR]

The article is devoted to identifying the origins and regional features of the technology of high-relief coinage in the Kazan-Tatar jewelry tradition. The main source was the electronic database of Tatar jewelry from museum collections, collected within the framework of the academic project “Jewelry of the Turkic peoples of Eurasia: general and special” (Russian Foundation for Basic Research 2013–2014, No. 13-06-97056). The research was based on a systematic technical and stylistic analysis of traditional jewelry and a detailed synchronous-diachronic examination of Bulgar-Golden Horde and Tatar products with three-dimensional images. Reconstruction of technological techniques related to this type of artistic metal processing made it possible to identify specific features of the formation of decor. The manual method of obtaining a unique relief using punches with a figured striker predominated. The decorations are characterized by the following: two or three-level bas-relief, the absence of a “locking” profile, the principle of “compositing” that underlies the conventionally interpreted floral and plant motifs, geometric orderliness, subject to the laws of the central-radial composition. The completed form of the decoration corresponds to the typical features of “notch chasing”, which is a marker of the Tatar craft tradition: smooth relief and “grain” background. An integrated approach allowed us to conclude that the origins of the existing artistic and figurative system can be traced in artifacts of the Bulgarian and Golden Horde silver of the 11th–14th centuries, made by embossing, stamping, and punching on a matrix. The formation of technological features was influenced by the traditions of high-relief coinage, which received regional development among Kazan silversmiths in the 17th–18th centuries. The specifics of Tatar relief coinage as a whole were formed in the context of Islamic art.

This paper discusses a low-cost technology for the fabrication of microfluidic devices on glass substrate using metal embossing technique. The fabrication technique demonstrated is a much simpler approach of embossing on glass using thermo-compression process with a patterned metal layer to define device structure. Well established printed circuit board fabrication photo-process is used to realize the desired planar geometry on metal layer deposited over a glass substrate. The depth of the channel is defined by the thickness of the metal deposited by electro-plating. The embossing technology offers a relatively safer approach conducive to batch processing to enable repeatable, high-yield, low-cost devices fabricated using low-cost equipment. Major challenges of achieving adhesion of the deposited thick nickel layer without peel-off and control of the thermo-compression process to achieve reliable and repeatable embossing without structural distortions were addressed. To prove its suitability for manufacturing, experiments were carried out with full wafer of 6″ × 6″ square glass wafer and optimal process steps for low-cost microfluidic device manufacturing have been well established. [ABSTRACT FROM AUTHOR]

Tissue paper is deep-rooted in our daily life because of its different types of products that allow various applications. Tissue paper is a low grammage paper that is mainly characterized by softness, tensile strength, liquid absorption, and elasticity. These characteristics are essential when producing products such as toilet paper, kitchen rolls, hand towels, napkins, and facials. The tissue paper production involves two stages: formation of the tissue paper sheet itself and its converting into different finished products. Converting is characterized by several operations, namely: unwinding, winding, embossing, lamination, perforation, cutting, packaging, and palletizing. The most impacting operation is the embossing, which consists of marking a pattern on the paper sheet by applying pressure, with the intent to produce papers more aesthetically pleasing to the final consumer and/or a way to identify a particular brand. Also, it affects final properties, increasing the liquid absorption capacity and bulk but reducing softness and tensile strength. Converting is complex and has a huge impact on the finished products properties. In this review, the authors explored the different steps of converting and how they impact the different properties of finished tissue products.

The requirements for embossing of cardboard for print and packaging applications are constantly increasing. High degrees of forming, richness of detail, and high shape accuracy are desired. However, current embossing technology can only fulfil these requirements to a limited extent. A loss of detail and moderate degrees of forming are typical defects in the embossing process. In previous research work, a positive effect on the forming behavior of cardboard could be observed by the application of ultrasound. Therefore, the influence of ultrasound was also investigated for embossing. In order to quantify the effects of ultrasound, conventional and ultrasonic-assisted embossing results were compared. New approaches for analysis and evaluation of embossing results and new characteristic values for describing the forming were applied for the comparison. Two exemplary embossing geometries and a range of ultrasonic parameters were used to characterize the impact of ultrasound and showed positive effects to the forming results.

The Bayanovo burial ground dating from the IX – first half of the X centuries is one of the most interesting medieval sites of Perm Cis-Urals . At the moment it is the most studied burial site of Lomovatovo archaeological culture (527 burials have been studied). The article deals with the results of the study of wooden scabbards with metal plates found during the excavation of the monument. Based on the collection, visual analysis of sources and their study with the help of different natural scientific methods, a detailed view of the design of items, the features of their manufacture and decoration techniques are given. The authors found out that birch was the main material for making the base of the scabbard. Birch, leather and textiles were also used. Thin sheets of pure copper or sheets of an alloy with a high silver content were used to make the metal plates of the scabbard. The decoration of the items was carried out with the help of various jewelry techniques. Often the artifacts were decorated with stamped wire with a grainy effect, triangles made of grains, incrustation or squeezed ornithomorphic and anthropomorphic images. Gilding applied with the help of amalgamation was also used.

Tissue paper is deep-rooted in our daily life because of its different types of products that allow various applications. Tissue paper is a low grammage paper that is mainly characterized by softness, tensile strength, liquid absorption, and elasticity. These characteristics are essential when producing products such as toilet paper, kitchen rolls, hand towels, napkins, and facials. The tissue paper production involves two stages: formation of the tissue paper sheet itself and its converting into different finished products. Converting is characterized by several operations, namely: unwinding, winding, embossing, lamination, perforation, cutting, packaging, and palletizing. The most impacting operation is the embossing, which consists of marking a pattern on the paper sheet by applying pressure, with the intent to produce papers more aesthetically pleasing to the final consumer and/or a way to identify a particular brand. Also, it affects final properties, increasing the liquid absorption capacity and bulk but reducing softness and tensile strength. Converting is complex and has a huge impact on the finished products properties. In this review, the authors explored the different steps of converting and how they impact the different properties of finished tissue products. [ABSTRACT FROM AUTHOR]

Ultrathin, lightweight, high-performance, low- cost, and energy-efficient loudspeakers that can be deployed over a wide area have become increasingly attractive to both traditional audio systems and emerging applications such as active noise control and immersive entertainment. In this article, a thin-film loudspeaker is proposed based on an active piezoelectric layer embossed with an array of microscale domes. Actuation of these freestanding domes contributes to excellent sound generation by the loudspeaker, for example, 86 dB sound pressure level at 30-cm distance with 25-V (rms) excitation at 10 kHz, regardless of the rigid surface on which it is bonded. The acoustic performance is further tunable by designing the dome dimensions. The proposed loudspeaker also exhibits high bandwidth, which extends its prospects into the ultrasonic range. The loudspeaker weighs only 2 g, is 120 μm thick and can be manufactured at low cost. These advantages make the proposed loudspeaker a promising candidate for ubiquitous applications in existing and emerging industrial and commercial scenarios. [ABSTRACT FROM AUTHOR]

In this study, the mechanical and thermal properties of poly(lactic acid) (PLA) blends with an addition of poly(ε–caprolactone) (PCL) and fumed silica (SiO2) were evaluated to research the possibility of their use as relief printing plates for embossing processes. PCL and nano-silica were added to the PLA matrix at different concentrations. Morphological, thermal and mechanical analyses were performed to determine the properties and possible functional characteristics of the studied blends. SEM micrographs showed that unmodified PLA/PCL blends exhibit a morphology typical of incompatible blends with clearly visible spherical domains of dispersed PCL in PLA. In particular, the results of the hardness tests showed that the selected blends have the optimal hardness (between 65 SH D and 75 SH D) for use in the embossing process. The tensile tests showed that the addition of nano-silica to neat PLA and to the PLA/PCL blends 50/50 and 60/40 improved the mechanical properties of the blends, especially stiffness and toughness. The DMA results showed that the addition of smaller amounts of SiO2 can contribute to an increase in storage modulus, which is due to good dispersion and distribution of SiO2 in the matrix. DSC analysis showed that the addition of PCL to PLA polymer increased the thermal stability of PLA and that the addition of nano-silica increased the degree of crystallinity of PLA. The TGA results showed that the addition of nano-silica improved the thermal degradation behavior of the studied blends, especially for blends modified with 3 wt% nano-silica. The results show that it is possible to optimize the mechanical and thermal properties of the blends with the aim of using them in the embossing process. [ABSTRACT FROM AUTHOR]

To evaluate whether processing a color fundus photo (CFP) using an image embossing technique can improve the detection of reticular pseudodrusen (RPD). This post-hoc analysis included the eyes of subjects enrolled in the Amish Eye Study with early or intermediate age-related macular degeneration and evidence of RPD. All patients underwent CFP, near-infrared reflectance (NIR), and fundus autofluorescence (FAF) imaging. The ground-truth presence of RPD was established with a combination of NIR and FAF imaging. An embossing processed (EP) image was created by replacing each pixel of the CFP image with a highlight or a shadow representing light and dark boundaries in the original CFP image. The presence of RPD in CFP and EP images was assessed by two graders in a masked fashion and the sensitivity of CFP and EP for detection of RPD was evaluated. Cohen's kappa (k) was used to test inter-grader agreement for CFP and EP. A total of 106 eyes from 62 patients with RPDs were analyzed. The sensitivity for detection of RPD on CFP and EP was 63.2% (95%CI: 52.0%–74.4%) and 91.5% (95%CI: 85.0%–98.0%), respectively. The inter-rater reliabilities of CFP and EP for RPD detection were 0.81 and 0.84, respectively. Embossing of CFP can improve the sensitivity for detection of RPD. The embossing technique can be a useful tool for better assessment of the true frequency of RPD in datasets where only CFP images are available. [ABSTRACT FROM AUTHOR]

The requirements for embossing of cardboard for print and packaging applications are constantly increasing. High degrees of forming, richness of detail, and high shape accuracy are desired. However, current embossing technology can only fulfil these requirements to a limited extent. A loss of detail and moderate degrees of forming are typical defects in the embossing process. In previous research work, a positive effect on the forming behavior of cardboard could be observed by the application of ultrasound. Therefore, the influence of ultrasound was also investigated for embossing. In order to quantify the effects of ultrasound, conventional and ultrasonic-assisted embossing results were compared. New approaches for analysis and evaluation of embossing results and new characteristic values for describing the forming were applied for the comparison. Two exemplary embossing geometries and a range of ultrasonic parameters were used to characterize the impact of ultrasound and showed positive effects to the forming results. [ABSTRACT FROM AUTHOR]

In the present work, an induction-aided hot embossing (IHE) setup was developed in-house, to reduce the time required for embossing. Using the setup, a micro-lens array was successfully fabricated over PMMA substrate using laser engraved mold in less than half the time required compared to traditional hot embossing. The operating parameters were optimized through composite desirability (CD) method and teaching learning-based optimization (TLBO) to enhance the replication accuracy of the embossed microlens array. IHE experiments were designed as per rotatable central composite design (R-CCD). Embossing temperature (Te), embossing pressure, embossing time, de-embossing temperature were selected as control parameters, and deviation in diameter of the embossed microlens array was chosen as performance factor. A first-order linear model was employed for mathematical modeling. ANOVA result reveals that the developed model is adequate and Te has an impact of 44.63% on the replication accuracy. It was observed that the deviation in diameter decreases from 27.12 μm to 23.63 μm as Te increases from 120ᵒC to 130ᵒC. Final optimization result reveals that TLBO performs better than the CD. Deviation in diameter predicted by TLBO method at optimum condition is 15.83 μm which closely matches the experimental findings at optimum condition, that is, 16.57 μm. Abbreviations HE: Hot embossing; PMMA: Polymethyl methacrylate; ROC: Radius of curvature; RSM: Response surface methodology; TLBO: Teaching learning-based optimization; CD: Composite desirability; ANOVA: Analysis of variance; To: room temperature; Tg: Glass transition temperature; Te: Embossing temperature; Pe: embossing pressure; te: embossing time; Tde: deembossing temperature; tc: Cycle time; μ: Micro; Ffrictional: Frictional force; RIE: Reactive ion etching; EDM: Electric discharge machining; h s a g : sag height; IP: Input; OP: Output; IHE: Induction-aided hot embossing; CHE: Conventional hot embossing; WEDM: Wire electric discharge machining [ABSTRACT FROM AUTHOR]

The potential for site-specific, process-parameter control is an attribute of additive manufacturing (AM) that makes it highly attractive as a manufacturing process. The research interest in the functionally grading material properties of numerous AM processes has been high for years. However, one of the issues that slows developmental progress in this area is process planning. It is not uncommon for manual programming methods and bespoke solutions to be utilized for site-specific control efforts. This article presents the development of slicing software that contains a fully automated process planning approach for enabling through-thickness, process-parameter control for a range of AM processes. The technique includes the use of parent and child geometries for controlling the locations of site-specific parameters, which are overlayed onto unmodified toolpaths, i.e., a vector-based planning approach is used in which additional information, such as melt pool size for large-scale metal AM processes, is assigned to the vectors. This technique has the potential for macro- and micro-structural modifications to printed objects. A proof-of-principle experiment is highlighted in which this technique was used to generate dynamic bead geometries that were deposited to induce a novel surface embossing effect, and additional software examples are presented that highlight software support for more complex objects. [ABSTRACT FROM AUTHOR]

To reduce the iron loss, motor cores are designed with many layers of silicon steel sheets, and these sheets are elastically joined using the embossed regions. In this study, we investigate how the embossing position affects the joining strength using 0.5-mm-thick silicon steel sheets. Specifically, we embossed and stacked pairs of rectangular specimens and then conducted separation tests. The separation force increased as the embossing position moved further from the specimen's edge. In addition, finite element analysis predicted the radial compressive stress of the interlocked projections, and it exhibits similar variation to the experimentally measured separation force with the changing embossing position. [ABSTRACT FROM AUTHOR]

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This paper studied the effect of embossing on the microstructure and corrosion behaviour of an Al−1.1 wt% Mn sheet. The microstructure of the embossed Al−1.1 wt% Mn sheets was studied by differential interference contrast microscopy, scanning electron microscopy, transmission electron microscopy, energy‐dispersive X‐ray spectroscopy, focused ion beam microscopy and X‐ray computational tomography. Finite element modelling was used to assess the stress and strain distribution developed during embossing, and to support the experimental analyses. The corrosion behaviour of the embossed sheets was assessed using potentiodynamic anodic polarisation tests, followed by corrosion surface morphology analysis. Results showed a microstructural evolution of the alloy during embossing, which is dependent on both the embossed pattern geometry and the roll forming direction. Nonsymmetrical displacement of material, in respect to the pattern geometry, was caused by the anisotropic forming pressure applied on the strip during roll forming, which yielded the formation of more susceptible sites for pitting and intergranular corrosion on the embossed aluminium surfaces. [ABSTRACT FROM AUTHOR]

In this study, the mechanical and thermal properties of poly(lactic acid) (PLA) blends with an addition of poly(ε–caprolactone) (PCL) and fumed silica (SiO2) were evaluated to research the possibility of their use as relief printing plates for embossing processes. PCL and nano-silica were added to the PLA matrix at different concentrations. Morphological, thermal and mechanical analyses were performed to determine the properties and possible functional characteristics of the studied blends. SEM micrographs showed that unmodified PLA/PCL blends exhibit a morphology typical of incompatible blends with clearly visible spherical domains of dispersed PCL in PLA. In particular, the results of the hardness tests showed that the selected blends have the optimal hardness (between 65 SH D and 75 SH D) for use in the embossing process. The tensile tests showed that the addition of nano-silica to neat PLA and to the PLA/PCL blends 50/50 and 60/40 improved the mechanical properties of the blends, especially stiffness and toughness. The DMA results showed that the addition of smaller amounts of SiO2 can contribute to an increase in storage modulus, which is due to good dispersion and distribution of SiO2 in the matrix. DSC analysis showed that the addition of PCL to PLA polymer increased the thermal stability of PLA and that the addition of nano-silica increased the degree of crystallinity of PLA. The TGA results showed that the addition of nano-silica improved the thermal degradation behavior of the studied blends, especially for blends modified with 3 wt% nano-silica. The results show that it is possible to optimize the mechanical and thermal properties of the blends with the aim of using them in the embossing process.

Targeted magnetic flux guidance in the rotor cross section of rotational electrical machines is crucial for the machine's efficiency. Cutouts in the electrical steel sheets are integrated in the rotor sheets for magnetic flux guidance. These cutouts create thin structures in the rotor sheets which limit the maximum achievable rotational speed under centrifugal forces and the maximum energy density of the rotating electrical machine. In this paper, embossing-induced residual stress, employing the magneto-mechanical Villari effect, is studied as an innovative and alternative flux barrier design with negligible mechanical material deterioration. The overall objective is to replace cutouts by embossings, increasing the mechanical strength of the rotor. The identification of suitable embossing geometries, distributions and methodologies for the local introduction of residual stress is a major challenge. This paper examines finely distributed pyramidal embossings and their effect on the magnetic material behavior. The study is based on simulation and measurements of specimen with a single line of twenty embossing points performed with different punch forces. The magnetic material behavior is analyzed using neutron grating interferometry and a single sheet tester. Numerical examinations using finite element analysis and microhardness measurements provide a more detailed understanding of the interaction of residual stress distribution and magnetic material properties. The results reveal that residual stress induced by embossing affects magnetic material properties. Process parameters can be applied to adjust the magnetic material deterioration and the effect of magnetic flux guidance. [ABSTRACT FROM AUTHOR]

The potential for site-specific, process-parameter control is an attribute of additive manufacturing (AM) that makes it highly attractive as a manufacturing process. The research interest in the functionally grading material properties of numerous AM processes has been high for years. However, one of the issues that slows developmental progress in this area is process planning. It is not uncommon for manual programming methods and bespoke solutions to be utilized for site-specific control efforts. This article presents the development of slicing software that contains a fully automated process planning approach for enabling through-thickness, process-parameter control for a range of AM processes. The technique includes the use of parent and child geometries for controlling the locations of site-specific parameters, which are overlayed onto unmodified toolpaths, i.e., a vector-based planning approach is used in which additional information, such as melt pool size for large-scale metal AM processes, is assigned to the vectors. This technique has the potential for macro- and micro-structural modifications to printed objects. A proof-of-principle experiment is highlighted in which this technique was used to generate dynamic bead geometries that were deposited to induce a novel surface embossing effect, and additional software examples are presented that highlight software support for more complex objects.

Generation of micron-scale structures on a substrate is an emerging area in the manufacturing sector owing to its application in different fields such as micro-lenses, micro-needles, micro-reactors, micro-pumps, etc. Specifically, a patterned polymer is a much-desired product having applications in optics, hydrophobicity, micro-fluidic chip, etc. Such structures can be fabricated through photolithography, micro-milling, laser ablation, etc. But these processes involve a large number of steps, which makes them time-consuming and prone to error. Also, some fabrication routes are not suitable for generating patterns on a polymer substrate. In hot embossing (HE), structures from a patterned mold are transferred on to a polymer substrate by application of an optimum amount of temperature and pressure. It has problems like a long cycle and non-uniform pressure distribution during the embossing stage. To overcome these problems, different variants such as gas-pressurized hot embossing, ultrasonic hot embossing, reel to reel hot embossing, inductive hot embossing, laser-assisted hot embossing, far infrared assisted hot embossing, etc. have been developed. This article aims to review state of the art in hot embossing setup development and to point out the scope for further work and the direction in which the research on hot embossing can progress in the future. [ABSTRACT FROM AUTHOR]

Current status of xinjiang machine-picked cotton primary processing research and measures to solve primary processing under lower temperature environment were discussed. Through the search literature data in CNKI and WOS, research status of domestic and foreign machine-picked cotton primary processing was analyzed. Xinjiang machine-picked cotton was taken as research object, processing equipment, moisture regain monitoring, drying equipment and cotton fiber property damage of machine-picked cotton primary processing were described. Problems in the lower temperature primary processing of Xinjiang machine-picked cotton were pointed out, corresponding solutions were proposed. It is considered that in view of the current status of machine-picked cotton primary processing, automated, intelligent and integrated quality management monitoring system should be established to promote the development of machine-picked cotton processing in the direction of streamline, digitization and safety. [ABSTRACT FROM AUTHOR]

Embossing is a commonly used design element on printed products and packaging. It enhances the product impression with optical and haptic effects. The material deformation during the embossing of cardboard is normally done using high mechanical pressure between two dies. The use of ultrasound in the embossing process leads to a noticeable reduction of the embossing pressure and a greater embossing precision. However, there is a noticeable heating of the cardboard during the ultrasonic-assisted embossing process. This work aimed to characterise the effects of heating and to understand the reasons for the greater precision with decreased force when ultrasound is used. Therefore, the effects of the thermal ultrasonic energy on the chemical composition and the morphological properties of the fibres were investigated. The findings showed that no noticeable changes occurred in the chemical composition or fibre geometry as a result of the embossing process with ultrasound. [ABSTRACT FROM AUTHOR]

The article is devoted to the identification and archaeological and ethnographic interpretation of technical and technological features of the Tatar jewelry art. Kazan was one of the largest jewelry centers in the Russian Empire, distinguished by the peculiarities of technical and technological and ornamental techniques of jewelry, formal and morphological content of jewelry. Tatar jewelers had a grip on almost all technological processes, but they acquired a special skill in the art of filigree and embossing. In historiography there was a belief that the so-called knobby filigree is “distinctive and unique appliances that have not received distribution in jewelry of other Nations” (Tatar encyclopedia, p. 468). However, recent research (RFFI, project № 13-06–97056) showed that it was common in the jewelry of some of the peoples of the European part of Eurasia since the 11th century. Analogues of Kazan Tatar lumpy filigree of the 18th – the first half of the 19th centuries were revealed for the first time in Russian (religious) and European (secular) traditions of jewelry art. Original kind Tatar coinage is the coinage identified by the researchers (F.H. Valeev) as a high-relief. On the products, which were made using this technique, presence (merger) of regional traditions characteristic of Tatar and Russian art have been revealed. Manifestations of syncretism, whoch are observed in a number of technologies of Tatar jewelry production, are probably due to the existence of numerous Russian jewelry centers in Kazan, the Kazan Volga region as a whole (usually in monasteries), including a large handicraft in the village of Rybnaya Sloboda.

During the embossing process, a fiber sandwich is compressed between embossing tools. The use of ultrasound causes a short-term increase in the material temperature in addition to causing plastic deformation. The combination of the material compression and an increase in material temperature leads to structural changes, which can be observed by the change in mechanical properties of the cardboard. This work investigated the influence of an ultrasonically induced temperature increase on the structural changes of cardboard. Using three-parameter combinations, different temperature levels were achieved with a material densification of less than 5%. Subsequently, the samples were subjected to selected physical and visual analyses to characterize the change in the fiber structure. With the increase of 124 °C material temperature there was a decrease of about 15% in the splitting resistance and 10% in the bending stiffness. [ABSTRACT FROM AUTHOR]

Developing research skills in budding engineers at the undergraduate level is a daunting task. Research thinking is an important skill that can be developed among students during their UG program, as it will lead to acquiring sound basics of the area of interest as well as develop innovating ideas. This will enhance the confidence of young engineers and their career opportunities. The proposed approach enables the student to undergo various phases listed as 1) Idea Generation 2) Defining Problem 3) Design of Procedures 4) Observation 5) Data analysis 6) Interpretation 7) Communication. Here we propose the objectives and the methodologies introduced for the systematic approach of finding a solution through the research process. The process involved is Identifying the research problem through the literature and market survey, devising a solution for the problem, building the prototype, and validating through standard tests. The proposed approach was followed under a well structured two-credit course called Research for Undergraduate(REU) planned for a selected group of students of Automation and Robotics program, which is highly inter-disciplinary. The research problem identified was the need for a low-cost solution for 3D printing on polyester fabric, a potential problem identified by many textile industries involved in the fabric printing process. Currently, the technology being used for fabric printing on polyester material is the Screen printing and Embossing methods with specific limitations. Also, the requirement was to incorporate the automation feature to print any computer-generated 3D models easily and in a flexible fashion by incorporating rapid prototyping technologies. The scope of research included the materials used for printing as well as building of the low-cost automated mechanism involving three-axis controls for laying of the material on the fabric. The standards for material testing were explored and were implemented for the selected polymer used for printing. Here, the methodologies introduced for the systematic approach of selection and testing of polymer used in printing, the building of automated printing mechanism prototype, and validating through standard tests are discussed. The performance of the developed prototype model of 3D printing mechanism is evaluated and analyzed. The mechanism was tested using two materials, namely, Silicone Rubber and the other Plastisol with puff ink for rated specifications, in terms of viscosity, flexibility, surface adhesion pressure, durability, dimensional stability, scratch resistance, and abrasion resistance.Liquid Plastisol with 30% puff ink yielded the optimum adhesion strength with better mechanical properties and good puffy appearance on polyester fabric. The mechanism to print liquid Plastisol is demonstrated by an X-Y plotter. A micropipette is placed as a liquid dispenser to lay the material in required design as per the NC codes generated from the SolidWorks software model. The control parameters are sent to the stepper motor drives through the Arduino controller to control the 3D mechanism. The proposed activity provided a lot of research insight into the design and development issues for both the students and the faculty coordinators. [ABSTRACT FROM AUTHOR]

Liquid crystal lenses have promise in optical systems owing to their tunability combined with low electrical power, cost, and weight. A good example of such a system is switchable contact lenses for the correction of age‐related presbyopia. Sufficiently large phase modulation can be done using nematic liquid crystals in a meniscus lens configuration. However, the birefringent materials are inherently polarisation dependent, usually requiring orthogonal polarisations to be focussed separately. A novel method is presented for producing polarisation independent lenses based on reactive mesogens. Results are presented for a 2‐level and 3‐level diffractive Fresnel lenses, and the promise of the technique for use in refractive lenses such as contact lenses is discussed. [ABSTRACT FROM AUTHOR]

This study provides an analysis of the hot embossing process with poly methyl methacrylate (PMMA) film. The hot embossing process engraves a fine pattern on a flexible film using a stamp, applied heat and pressure. As the quality of the embossing pattern varies according to various process variables, the mechanism of making the embossed shape is complicated and difficult to analyze. Therefore, analysis takes much time and cost because it usually has to perform a lot of experiments to find an appropriate process condition. In this paper, the hot embossing process was analyzed using a computational analysis method to quickly find the optimal process. To do this, we analyzed the embossing phenomenon using the finite element method (FEM) and arbitrary Lagrangian–Eulerian (ALE) re-mesh technique. For this purpose, we developed a constitutive model considering the strain, strain rate, temperature-dependent stress and softening of the flexible film. Work hardening, strain softening, and temperature-softening behavior of PMMA materials were well described by the proposed method. The developed constitutive model were applied in the embossing analysis via user-subroutine. This proposed method allowed a precise analysis of the phenomenon of film change during the hot embossing process.

Small-scale optical components with micron or submicron features have grown in popularity in recent years. High-quality, high-efficient, and cost-effective processing approaches for polymer optics mass production are an urgent need. In this study, ultrasonic vibration will be introduced in embossing. The major advantage is that the required energy can be provided for process times ranging from a few hundred milliseconds to a few seconds, and that the process energy is provided at exactly the required location so that the structures in the surrounding area are not affected. Due to the strong correlation between electrical impedance and the temperature of the material, a novel impedance-based control strategy has been utilized for precisely controlling ultrasonic vibration during the embossing process. The investigation used two types of stamps with grating line widths of 4 µm and 500 nm, respectively. As a result, an embossing time of less than a few seconds was accomplished and a uniform embossed surface with an average fill rate of more than 75% could be achieved.

A major challenge in manufacturing polymer-metal electronic systems, for example, encapsulations of metal inserts using assembly injection molding, is to create a tight sealing in order to prevent leakage. One typical reason for leakage is the formation of gaps between polymer and metal. Through labyrinth seals, which can be manufactured by structuring of the metal surface, the gap-based leakage networks can be interrupted. However, in order to use the appropriate structure in the right position, knowledge about the formation of the gaps is essential. The research covered in this paper focuses on the analysis of the formation of gap-based leakages in polymer-metal electronic systems with labyrinth seals to improve the component design of such parts. The effects of different embossed labyrinth seals, which differ in depth and features, and an electrochemically manufactured areal seal on the tightness and leakage position are investigated. Furthermore, the formation of the leakage network is presented for the investigated variants. [ABSTRACT FROM AUTHOR]

Abstract Titanium implants are widely used in load bearing applications. Failure analysis for several decades revealed poor interfacial bonding at implant-tissue interface is the major cause. Diverse morphological and chemical modifications are carried out to overcome to this issue. In this study, we developed a simple, user friendly combinatorial approach of embossing followed by hydrothermal treatment for generating nano/micro/macro hierarchical architecture on Ti6Al4V surface with deposition of calcium phosphate minerals for improving osseointegration property. The hydrothermally treated groove/pillar patterned sample had uniformly distributed nanorods with 65 ± 3 nm diameter, surface roughness ~118 nm and ~532 nm height, respectively. Presence of phosphate and calcium were confirmed through EDS and XRD with Ca/P ratio ~1.66 which is similar to apatite like deposition. Calcium phosphate apatite formation was also confirmed on the surface by XPS. The hydrothermal treated samples demonstrated improved hMSC cell adhesion, migration, proliferation and differentiation as compared to untreated ones. Therefore, this method has potential to minimize interfacial failure through morphological fixation via tissue ingrowth as well as ongrowth. Graphical abstract Unlabelled Image Highlights • A simple method to develop nano/micro/macro hierarchy on Ti6Al4V via patterning and hydrothermal treatment. • The method minimizes interfacial failure through morphological fixation via tissue ingrowth as well as ongrowth. • Presence of calcium phosphate apatite was noted which proved beneficial for stem cell differentiation. • hMSC proliferation was significantly higher on treated samples as compared to untreated one. [ABSTRACT FROM AUTHOR]

Liquid crystal lenses have promise in optical systems owing to their tunability combined with low electrical power, cost and weight. A good example of such a system is switchable contact lenses for the correction of age‐related presbyopia. Large phase modulation can be done using nematic liquid crystals. However, the birefringent materials are inherently polarisation dependent, usually requiring orthogonal polarisations to be focused separately. A novel method is presented for producing polarisation independent lenses based on reactive mesogens. [ABSTRACT FROM AUTHOR]

Abstract The brain stores memories by persistently changing the connectivity between neurons. Sleep is known to be critical for these changes to endure. Research on the neurobiology of sleep and the mechanisms of long-term synaptic plasticity has provided data in support of various theories of how brain activity during sleep affects long-term synaptic plasticity. The experimental findings – and therefore the theories – are apparently quite contradictory, with some evidence pointing to a role of sleep in the forgetting of irrelevant memories, whereas other results indicate that sleep supports the reinforcement of the most valuable recollections. A unified theoretical framework is in need. Computational modeling and simulation provide grounds for the quantitative testing and comparison of theoretical predictions and observed data, and might serve as a strategy to organize the rather complicated and diverse pool of data and methodologies used in sleep research. This review article outlines the emerging progress in the computational modeling and simulation of the main theories on the role of sleep in memory consolidation. [ABSTRACT FROM AUTHOR]

Due to the permanently increasing maximum speed of modern electric machines, the mechanical load on the electrical steel rises. The punched flux barriers of reluctance machines play an increasingly key role in the mechanical design. The weakening of the material and the notching effect can cause local failure due to centrifugal force. In this paper, a method is presented which induces residual stresses by embossing electrical steel laminations, which contribute to the guidance of the magnetic flux and cause a negligible mechanical weakening of the sheet. The aim of this paper is to demonstrate the effectiveness of these embossed flux barriers. This is achieved by using neutron grating interferometry, that allows the density of the magnetic domains to be resolved locally. Furthermore the influence of the embossing is mapped globally by single sheet tests. The finite element analysis of the forming process derives the residual stress distribution which is responsible for the measured magnetic behavior. In order to isolate the influence of the residual stress, non-embossed and stress-relief annealed specimens are used as a reference for both measurement methods. [ABSTRACT FROM AUTHOR]