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[EN] Accounting for the flood routing effect of reservoirs in the assessment of flood discharges is essential in basins where the hydrology is conditioned by the presence of one or more dams. This paper presents the implementation of reservoirs and dams in the hydrological module of the software Iber, which solves the two-dimensional shallow water equations at the scale of an entire basin. Spillways with and without gates, low level outlets, and the possibility to define an ad hoc outflow curve relating the flow rate to the reservoir level are included. As a case study, the effect of the Iznájar reservoir on the hydrology of the Genil basin in Spain was modelled. Three scenarios were considered to compare the effect of the different outflow structures included in this new implementation in Iber. The defined methodology proves to be able to represent numerically the outflow structures, addressing a fundamental limitation in the modelling of large basins with Iber., [ES] La consideración del efecto laminador de los embalses en la evaluación de caudales de avenida es un aspecto fundamental en aquellas cuencas donde la hidrología está condicionada por la presencia de presas. En este trabajo se presenta la implementación de embalses y presas en el módulo hidrológico del modelo Iber, el cual resuelve las ecuaciones de aguas someras bidimensionales a escala de toda una cuenca. Para la modelización del caudal de salida del embalse se incluyen aliviaderos con y sin compuerta, desagües de fondo y la posibilidad de definir una curva de desagüe ad hoc que relacione el caudal de salida con el nivel del embalse. Como caso de estudio se modeló el efecto del embalse de Iznájar en la hidrología de la cuenca del río Genil, en España. Se consideraron tres hipótesis de cálculo con el fin de comparar el efecto de los diferentes órganos de desagüe definidos en esta nueva implementación en Iber. La metodología definida demuestra ser capaz de representar numéricamente los órganos de gestión del embalse y resolver así una limitación fundamental en el modelado de grandes cuencas con Iber., La investigación que aquí se presenta ha sido financiada por el proyecto EAPA_45/2018_AA-FLOODS

Fotovoltaik (FV) modüller, üzerine düşen güneş ışınlarından elektrik üretimini sağlayan ve yüzeyinde birden çok FV hücre bulunan yapılardır. FV hücreler, sadece direkt gelen ışınları değil, yüzeye gelen tüm ışığın belirli dalgaboyu aralığını enerji üretimi için kullanabilirler. FV modüller, yapıları gereği sıcaklıkları, ortam sıcaklığına kıyasla daha fazla olmakta ve bu durum FV hücrelerin elektriksel verim ve güç üretim düşümüne neden olmaktadır. Bu sebeple, FV modüllerde depolanan ısı enerjisinin dışarıya transferi konusunda akademik çalışmalar son yıllarda ivme kazanmıştır. Örneğin, FV modüllerden ısı enerjisi elde edilerek sıfır enerji tüketim hedefi altında konutların ısıtma yükü karşılanmakta ve ilerleyen çalışmalar ile birlikte sistem/enerji verimi arttırılmaktadır. Bu çalışma, FV modüllerin ısı iletim performansının geliştirilmesine yönelik polimer esaslı takviye malzemelerin kullanımı ile oluşturulan kompozit yapılar incelenerek, FV modülde depolanan ısı enerjisinin azaltılmasını hedef almıştır. Bu amaçla, takviye malzemeler araştırılmış ve karbon, cam elyaf, aramid (kevlar) takviye malzemelerinin iki farklı parametre altında araştırılması uygun görülmüştür. Bu iki parametre, herbir takviye malzemenin farklı tabaka kalınlıklarındaki ve birbirleri ile oluşturduğu hibrit yapıdaki sahip oldukları ısı iletim performansını araştırmaktadır. Araştırma sonucunda karbon elyaf takviye malzemesi ile oluşturulan yapının 6,51 W/mm2 ısı akısı ile birlikte optimum yapı olduğu elde edilmiştir. Isı iletim performansında karbon elyafı cam elyaf (0,013 W/mm2) ve aramid (4.10-4 W/mm2) takip etmiştir. Bu araştırma polimer kompozit malzemeler ile lamine edilmiş FV modül ve konvansiyonel tip FV modül arasındaki ısı akısı farkını 0,0242 W/mm2 olarak elde ederek FV modüllerden elde edilebilen ısı enerjisinin arttırımına katkıda bulunmuştur., Photovoltaic (PV) modules are structures that produce electricity from the sun's rays falling on them and have more than one PV cell on their surface. PV cells can use not only direct rays, but also a certain wavelength range of all light coming to the surface for energy production. Due to their nature, PV modules have a higher temperature compared to the ambient temperature, which causes a decrease in the electrical efficiency and power generation of the PV cells. For this reason, academic studies on the transfer of heat energy stored in PV modules to outside have gained momentum in recent years. For example, by obtaining heat energy from PV modules, the heating load of the houses is met under the target of zero energy consumption, and the system/energy efficiency is increased with further work. This study aimed to reduce the heat energy stored in the PV module by examining the composite structures formed using polymer-based reinforcement materials to improve the heat conduction performance of PV modules. For this purpose, reinforcement materials were investigated, and it was found appropriate to investigate carbon, glass fiber, aramid (Kevlar) reinforcement materials under two different parameters. These two parameters investigate the heat conduction performance of each reinforcement material in different layer thicknesses and in the hybrid structure formed with each other. As a result of the research, it has been obtained that the structure formed with carbon fiber reinforcement material is the optimum structure with a heat flux of 6.51 W/mm2. In heat conduction performance, carbon fiber was followed by glass fiber (0.013 W/mm2) and aramid (4.10-4 W/mm2). This research contributed to the increase of the heat energy that can be obtained from PV modules by obtaining the heat flux difference between the PV module and the conventional type of PV module laminated with polymer composite materials as 0.0242 W/mm2.

As is well known, the magnetostrictive phenomenon of electrical steel sheet is the main source of electricity in equipment such as transformers. The magnetostrictive characteristic of the actual transformer core is more complicated than that of single-sheet steel. The magnetostriction phenomenon of the transformer core cannot be fully understood by studying only a single piece of electrical steel, so it is necessary to study the local magnetic characteristics of the transformer directly. In this paper, two-limb, one-phase transformer core with a multi-step-lap construction was assembled, a laminated magnetostrictive testing system based on triaxial strain gauges was built, and the local magnetic characteristics were studied using a self-developed B-H vector sensor. The magnetostrictive and magnetic properties in different local regions were measured and analyzed under several magnetization patterns, and the influence of DC bias on the magnetostrictive property of the corner, yoke, and limb of the core was investigated. The influence of the position of the clamp on the magnetostriction of the transformer core was also studied. The magnetostrictive strain of the single sheet and laminated core was compared and discussed. The results showed that the strain caused by the interaction between laminations in this area can be effectively reduced when clamping in the middle of the yoke.

In this study, the modulus of elasticity and flexural strength properties of laminated wood elements reinforced with steel mesh with different mesh openings were determined. In accordance with the purpose of the study, three- and five-layer laminated elements were produced from scotch pine (Pinus sylvestris L.) wood material, which is widely used in the wood construction industry in Türkiye. The 50, 70, and 90 mesh steel used as the support layer was placed between each lamella and pressed with polyvinylacetate (PVAc-D4) and polyurethane (PUR-D4) adhesives. Afterward, the prepared test samples were kept for 3 weeks at 20 °C temperature and 65 ± 5% relative humidity for 3 weeks. The flexural strength and modulus of elasticity in flexural of the prepared test samples were determined according to the TS EN 408: 2010+A1 standard by the Zwick universal tester. Multiple analysis of variance (MANOVA) was carried out using MSTAT-C 1.2 software to determine the effect of the modulus of elasticity and flexural strength on the obtained flexural properties, the mesh opening of the support layer, and the adhesive type. When the differences within or between groups were significant with a margin of error of 0.05, achievement rankings were made using the Duncan test on the basis of the least significant difference. According to the results of the research, the highest bending strength (120.3 N/mm2) was obtained in three-layer samples reinforced with 50 mesh steel wire and bonded with Pol-D4 glue, and the highest modulus of elasticity (8969.3 N/mm2) was obtained in three-layer samples reinforced with 50 mesh steel wire and bonded with Pol-D4 glue. As a result, the reinforcement of the laminated wood material with steel wire had an increasing effect on the strength. Accordingly, the use of 50 mesh steel wire can be recommended to increase mechanical properties.

Investigations of historical conservation materials on historical stained glass windows of the Naumburg Cathedral in Germany offered an opportunity for the study of polymers, naturally aged in a non-controlled environment. This allowed the conservation history of the cathedral to be traced and expanded by valuable insights. The historical materials were characterized through the use of spectroscopy (FTIR, Raman), thermal analysis, PY-GC/MS, and SEC on taken samples. The analyses show that acrylate resins were predominantly used for conservation. The lamination material from the 1940s is particularly noteworthy. Epoxy resins were also identified in isolated cases. Artificial aging was used to investigate the influence of environmental influences on the properties of the identified materials. Through a multi-stage aging program, influences of UV radiation, high temperatures and high humidity can be considered in isolation. Piaflex F20, Epilox, Paraloid B72 as a modern material and combinations of Paraloid B72/diisobutyl phthalate and PMA/diisobutyl phthalate were investigated. The parameters yellowing, FTIR spectra, Raman spectra, molecular mass and conformation, glass transition temperature, thermal behavior, and adhesive strength on glass were determined. The effects of the environmental parameters on the investigated materials are differentiated. UV and extreme temperatures tend to show a stronger influence than humidity. The comparison of the artificially aged samples with the naturally aged samples from the cathedral shows that the latter were less aged. Recommendations for the conservation of the historical stained glass windows were derived from the results of the investigation.

Kako bi se minimizirali gubitci zbog vrtložnih struja, lamelirana transformatorska jezgra se sastoji od velikog broja vrlo tankih feromagnetskih lamela međusobno odvojenih višestruko tanjim slojevima električne izolacije. Očekivano, konačna rješenja za elektromagnetska polja u tako heterogenom području su vrlo oscilatorne, samo po dijelovima kontinuirane prostorne funkcije. Kako bi aproksimacija rješenja bila valjana, izravna primjena metode konačnih elemenata na takav problem zahtijeva iznimno gustu mrežu konačnih elemenata, tj. prekomjeran broj konačnih elemenata iz perspektive raspoloživih računalnih resursa. Prema tome, nužno je provesti neki vid homogenizacije fizikalne slike. U slučaju jezgre otvorenog tipa, situacija se dodatno komplicira zbog neravnomjerne razdiobe elektromagnetskih polja u volumenu jezgre. Značajan dio magnetskog toka prodire u jezgru okomito na plohe lamela, a tako inducirane vrtložne struje poprimaju značajne iznose. Kako bi se smanjio njihov iznos, jezgra otvorenog tipa se obično izvodi od više vitkijih dijelova, tj. laminacijskih paketa, međusobno odvojenih dodatnim slojevima električne izolacije. Sa stajalište računalnih simulacija, takvi slojevi izolacije kvare brzinu konvergencije, a njihova homogenizacija nije moguća korištenjem standardnih metoda. Specifičnosti fizikalne slike kod jezgre otvorenog tipa moguće je uspješno uzeti u obzir korištenjem magnetskog vektorskog potencijala A i strujnog vektorskog potencijala T. U skladu s tim, najprije je izvedena Galerkinova slaba A,T – A-formulacija temeljena na izravnoj primjeni metode konačnih elemenata. Kako bi se znatno smanjila potrebna gustoća diskretizacije domene, unutar svakog pojedinog konačnog elementa su uvedene prikladne aproksimacije fizikalne slike u vidu raspregnutih, međusobno neovisnih elektromagnetskih polja. Na osnovu uvedenih aproksimacija, izvedena je modificirana slaba formulacija koja dopušta znatno veće dimenzije konačnog elementa, ali vrijedi samo lokalno, unutar volumena promatranog konačnog elementa. No, homogenizacijom takve modificirane formulacije dobiva se Galerkinova A,Tx – A-formulacija koja je valjana globalno, unutar cijele problemske domene. Kao posljedica postupka homogenizacije, u području jezgre se koriste nadomjesne homogene i anizotropne značajke materijala. Konačna A,Tx – A-formulacija omogućuje simultano modeliranje sveukupnih vrtložnih struja u jezgri. Dodatno, za razliku od početne slabe A,T – A-formulacije, homogenizirana slaba A,Tx – A-formulacija pokazuje odličnu brzinu konvergencije. Pored analitičkog postupka homogenizacije, razvijen je i numerički pristup homogenizaciji temeljen na 2D formulaciji problema vrtložnih struja kojim se uspješno homogeniziraju i rubni efekti vrtložnih struja, tj. promjene smjera vrtložnih struja koje se javljaju na rubovima lamela. Napravljena je usporedba računalne simulacije temeljene na A,Tx – A-formulaciji s računalnom simulacijom temeljenom na A,φ – A-formulaciji. Dobiveno je dobro slaganje rezultata računalnih simulacija, s tim da simulacija temeljena na A,Tx – A-formulaciji pokazuje bržu konvergenciju. Dodatno, razvijena metoda je primijenjena za izračun gubitaka u realnoj jezgri otvorenoga tipa za koju su prethodno provedena mjerenja ukupnih gubitaka. Rezultati simulacije se dobro slažu s rezultatima dobivenim putem mjerenja, što dodatno potvrđuje valjanost razvijene metode. In order to minimize eddy current losses, the laminated transformer core consists of a large number of very thin ferromagnetic laminations separated from each other by much thinner layers of electrical insulation. As expected, the final solutions for electromagnetic fields in such a heterogeneous region are highly oscillatory, piecewise continuous spatial functions. In order for the approximation of the solution to be valid, the direct application of the finite element method to such a problem requires an extremely dense finite element mesh, i.e., an excessive number of finite elements from the perspective of available computing resources. Therefore, it is necessary to carry out some kind of homogenization of the equations. In the case of an open-type core, the situation is further complicated by the uneven distribution of electromagnetic fields in the core volume. A significant part of the magnetic flux penetrates into the core perpendicular to the surfaces of the laminations, and the eddy currents thus induced have significant values. In order to reduce their amount, the open-type core is usually made of several slimmer parts, i.e. lamination packages, separated from each other by additional layers of electrical insulation. From the point of view of computer simulations, such layers of isolation reduce the speed of convergence, and their homogenization is not possible using standard methods. The specificities of the open-type core can be successfully taken into account using the magnetic vector potential A and the current vector potential T. Accordingly, Galerkin's weak A,T – A-formulation based on the direct application of the finite element method was first derived. In order to significantly reduce the required density of domain discretization, appropriate approximations in the form of uncoupled, mutually independent electromagnetic fields were introduced within each individual finite element. On the basis of the introduced approximations, a modified weak formulation was derived that allows significantly larger dimensions of the finite element, but is valid only locally, within the volume of the observed finite element. However, the homogenization of such a modified formulation gives the Galerkin A,Tx – A-formulation, which is valid globally, within the entire problem domain. As a consequence of the homogenization process, new homogeneous and anisotropic material features are used in the core region. The final A,Tx – A-formulation enables the simultaneous modeling of all eddy currents in the core. Additionally, unlike the initial weak A,T – A-formulation, the homogenized weak A,Tx – A-formulation shows an excellent convergence rate. In addition to the analytical homogenization procedure, a numerical approach to homogenization was developed based on the 2D formulation of the eddy current problem, which takes into account the edge effects of eddy currents, i.e., changes in the direction of eddy currents that occur at the edges of lamin ations. A comparison was made between the simulation based on the A,Tx – A-formulation and the simulation based on the A,φ – A-formulation . A good agreement of the simulation results was obtained, and the simulation based on the A,Tx – A-formulation shows a better convergence rate. Additionally, the developed method was applied to the calculation of losses in a real open-type core for which total losses were previously measured. The simulation results are in good agreement with the results obtained through measurements, which additionally confirms the validity of the developed method.

Accurate and precised analysis is the significant phenomenon in the development of any engineering application. Engineering materials are being employed in several engineering applications after performing many sorts of strength analyses. In recent days, natural fiber composite materials are used as alternative materials for steel and alloy materials in many engineering applications because of few special features such as better strength to weight ratio and pollution free nature. While they are being employed in higher level applications, failure analyses which are capable of providing precised results need to be used. In this regard, several attempts have been taken for providing analytical formulation to calculate the free edge stress values induced in natural fiber composite materials accurately. In this investigation, an attempt has been made to apply the proposed theory on four applications – Bamboo composite furniture, Kevlar composite Aero wing, Natural composite safety Helmet and Bullet proof vehicle’s body. The results were compared with Classical Lamination Plate theory for validation.

Dielectric elastomer transducers (DETs) consist of thin elastomer films and compliant conductive electrodes on each side. Several DE-based systems, e.g., DE actuators, loudspeakers or sensors, have great potential in industrial applications. Different manufacturing processes for DE-based transducers have been realized so far. An alternative manufacturing process, based on sheet-to-sheet lamination of pre-fabricated elastomer films, appears promising for the manufacturing of large numbers of DETs, as, on the one hand, the commercially available elastomer films produced are characterized by homogeneous and reproducible properties and, on the other hand, the curing time during processing can be avoided. However, the handling of thin elastomer films and a controlled film transfer onto a surface is a challenge, as pre-stretch and wrinkles can easily occur. The presented sheet-to-sheet lamination mechanism facilitates controllable film handling well, whereby a high number of DE layers can be achieved. This paper focuses on the developed, automated film lamination of pre-cut film sheets and the electrode application via a jetting system, representing core components of the corresponding overall manufacturing process of DE laminates. The process realization on a laboratory scale is presented and manufactured DET specimens investigated for validation purposes.

The chapter reviews the application of creep-recovery and oscillatory rheological tests in flour based systems, including simple flour water systems, and more complex ones, such as bread, cookies and biscuits. A theoretical introduction about the fundaments and methods of linear viscoelastic rheology is presented, including general mathematical models and their application in flour based systems. A summary of experimental conditions to perform the rheological tests is covered. Functionality of flour based systems is extremely dependent on their viscoelastic properties. Processes like mixing, pumping, lamination, baking performance have been found to be strongly dependent on the system viscoelastic properties. However, the establishment of general and well-defined relationships among viscoelastic properties and specific functionalities is quite a difficult task, still on progress.

For manufacturing Multilayer Systems for vertical functional integration with small structures, the R2R process offers a high potential for cost reduction. The focus of the dissertation is on the design and implementation of a system for web manipulation using contactless web guidance, as well as the detection and correction of inhomogeneous web tension distributions. It is investigated to what extent such a system is suitable for a continuous multilayer lamination process.

Historically, the Trustees of the Library always ensured that there were funds to repair and rebind the books in their care. The sums given varied and increased as new preservation and conservation techniques were devised. The latter included deacidifcation and lamination. Treatments were applied by the bindery located at the British Museum in Great Russell Street and by external firms. Towards the end of the twentieth century, procedures were laid down to ensure the books were suitably repaired or rebound according to a variety of contracts and staff were put in place to organise and supervise. From 1982 to 1997, Ed King was Head of Preparation and Selection programmes for Binding and Conservation (of Printed Books), and he has prepared a report of how preservation and binding were administered., UK

Depending on the stator lamination manufacturing processes (e.g., punching, laser cutting, clamping, welding, interlocking, and bonding), the motor’s magnetic performance parameters, such as cogging torque, hysteresis torque, and iron losses, can vary significantly. In sub-fractional horsepower (SFHP) permanent magnet motors, the manufacturing influence is typically even more severe because, due to their small dimensions, practically, the whole stator material is likely to be affected. This article analyzes the magnetic performance parameters cogging torque, hysteresis torque, and iron losses of three different stator lamination stacks (i.e., M250-35A punched with interlocking, M250-35A laser cut with bonding, and NO10 laser cut with bonding) of an SFHP single-phase brushless permanent magnet motor often found in automotive fan applications. A rheometer is used for extremely accurate torque measurements in the sub-millinewton meter range, and electron backscatter diffraction measurements are performed to visualize changes in the grain morphology and crystal orientation. The findings reveal that the punched stator with interlocking is affected the most by the manufacturing process, showing the lowest cogging torque yet the highest average hysteresis torque and thus up to 40% higher iron losses. The results presented in this article allow for both making basic stator lamination design choices and translating the iron losses, as well as the hysteresis torque and cogging torque waveforms, of a laser cut and bonded prototype into those of its punched and interlocked mass-produced counterpart.

Composite materials are being used in many weight-sensitive applications due to their attractive features of high strength-to-weight and stiffness-to-weight ratios and design flexibility. In harsh dynamic environments, excitation frequencies can lead to resonance at some frequency bands, impacting the integrity and functionality of the whole composite structure. Adding patches to the main structure at periodic locations introduces stopbands, which are frequency bands where vibration amplitudes are highly attenuated, and natural frequencies are absent. Using composite materials in such periodic patches enables more design flexibility that can be used to generate stopbands at desired frequency ranges. This paper presents a design approach for periodic laminated composite beams to obtain the patch length and stacking sequence that realize the desired start and end stopband frequencies. Based on the reverse approach of the wave finite element (WFE) method, the proposed design approach includes solving two nonlinear algebraic equations to find the design point. Then, a search for all possible patch stacking sequences that realize this design point and achieve the target stopband with the least possible error is done. The design approach was validated by demonstrating that it generates the inputs that were used by an analysis code to generate the design code inputs. Various examples are presented with different stopband ranges, fiber-orientation angles and materials of the substrate and patch plies. It is shown that depending on the substrate material, number of plies per patch and desired stopband start and end frequencies, one can obtain several possible stacking sequences that can realize the design. The study focuses on beam bending modes in the 0–2000 Hz frequency range, where classical lamination and Euler-Bernoulli’s beam theories are valid.

Buckling problem of composite plates is of importance since it is commonly encountered in thin-walled structural components in engineering. Buckling resistance design of composite plates involves the design of laminate stacking sequence exhibiting high dimensional discrete variables owing to the combination and permutation of ply orientations of layers. In this work, a sequential permutation search (SPS) optimization algorithm is presented for the stacking sequence design of composite rectangular plates accounting for the inherent physical-mechanical behavior of composite laminates. Owing to that the governing equation for buckling of composite rectangular plates is a linear homogeneous equation on bending stiffness parameters, the convexity of flexural lamination parameters and sensitivity of bending stiffness are utilized to construct sensitive detection techniques and linear search procedures. Moreover, to increase the robustness of SPS, a sign optimization algorithm (SOA) is coupled in SPS to regulate bending-twisting coupling effects. The SPS algorithm is applied to the buckling resistance design of composite rectangular plates exhibiting various boundaries under axial compression, where the Rayleigh-Ritz method is developed to perform the buckling analysis. Optimal results of SPS are compared against layerwise optimization approach (LOA) and genetic algorithm (GA), illustrating its reliability and efficiency.

The optimal design of laminates of interlayer hybrid lamination with multicouplings is significantly beneficial to enhance the mechanical properties and reduce the cost of composite structures. The...

Bambusa Arundinacea slat lamination has relatively high tensile and flexure strength, while Pterocarpus Indicus has relatively lower than. These two types of bio-materials are very cheap, easy to cultivate, fast growing, and renewable material. For this reason, hybrid slats lamination of Bambusa Arundinacea and Pterocarpus Indicus was chosen as a construction material for fishing boats to substitute solid Teak wood which is increasingly rare and expensive. Based on the results of the tensile and flexural strength tests show that the configuration of the hybrid laminated with the parallel slats has the highest tensile strength (114.636 MPa) and flexural strength (111.606 MPa). These two strength values are used to calculate the 20GT fishing boat scantling in accordance with the Indonesian Classification Bureau vol vii 2013 regulations. By using the hybrid lamination material of Bambusa Arundinacea - Pterocarpus Indicus slats, the scantling of 20GT fishing boat will be slightly smaller, the volume of material needed is 28.7% lower and the construction cost 40.66.% less than Teak wood material.

Carbon Fiber Reinforced Polymer (CFRP) was designed, simulated, and evaluated as a wrapping material on defected pipe using computational approach. This composite material was considered as a unique wrapping material as it may have the combined characteristics of the constituents or have substantially different properties than the individual constituents. Specifically, this research evaluates the capability of CFRP as a wrapper through SolidWorks Simulation using the static analysis, computational fluid dynamics analysis, and data analysis. This approach gives a preliminary consideration and justification on choosing the optimized lamination orientation of CFRP in real cases based on the simulated data. Various orientations were simulated and analyzed throughout this research. Based on all the simulation analysis, the CFRP wrapper with quasi-isotropic lamination with the 8 plies \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\left(45^\circ /90^\circ /0^\circ /45^\circ \right)}_{\mathrm{s}}$$\end{document}45∘/90∘/0∘/45∘s orientation was seen most effective in reducing the stress and possess highest minimum safety factor at the fully defected region (100 × 100 × 7.11 mm thru) after the repair. Eventually, this optimized CFRP lamination orientation, proved that it was able to withstand pressures ranging between 0.86 to 19.6 MPa with a layer thickness in between 0.16 up to 3.76 mm. Based on the static analysis, this optimized laminated orientation of CFRP indeed showed that it was able to reduce the stress on an average of 94.10% after the repair was done. Relatively, CFRP was 0.2% higher in reducing the maximum stress at the defected region at the pipe, than the Glass Fiber Reinforced Polymer with the same orientation. Additionally, the flow simulation analysis in SolidWorks showed that fluid flow was undisrupted after the repair was done, and the wrapped region was resistant to any fluid leakages.

Cetartiodactyls include terrestrial and marine species, all generally endowed with a comparatively lateral position of their eyes and a relatively limited binocular field of vision. To this day, our understanding of the visual system in mammals beyond the few studied animal models remains limited. In the present study, we examined the primary visual cortex of Cetartiodactyls that live on land (sheep, Père David deer, giraffe); in the sea (bottlenose dolphin, Risso’s dolphin, long-finned pilot whale, Cuvier’s beaked whale, sperm whale and fin whale); or in an amphibious environment (hippopotamus). We also sampled and studied the visual cortex of the horse (a closely related perissodactyl) and two primates (chimpanzee and pig-tailed macaque) for comparison. Our histochemical and immunohistochemical results indicate that the visual cortex of Cetartiodactyls is characterized by a peculiar organization, structure, and complexity of the cortical column. We noted a general lesser lamination compared to simians, with diminished density, and an apparent simplification of the intra- and extra-columnar connections. The presence and distribution of calcium-binding proteins indicated a notable absence of parvalbumin in water species and a strong reduction of layer 4, usually enlarged in the striated cortex, seemingly replaced by a more diffuse distribution in neighboring layers. Consequently, thalamo-cortical inputs are apparently directed to the higher layers of the column. Computer analyses and statistical evaluation of the data confirmed the results and indicated a substantial correlation between eye placement and cortical structure, with a markedly segregated pattern in cetaceans compared to other mammals. Furthermore, cetacean species showed several types of cortical lamination which may reflect differences in function, possibly related to depth of foraging and consequent progressive disappearance of light, and increased importance of echolocation.

Removing the outer part of bamboo for manufacturing flat bamboo lamination has disadvantage on the density of the product. The purpose of this experiment was to investigate the fixation of compressed bamboo from curved cross-section slats. The compression of bamboo slats using densification technique was aimed for uniform density. Furthermore, steam treatments were conducted to fix the deformation. The compressed bamboo slats revealed that the density of the samples at the bottom parts increased from 0.40–0.56 g/cm3 to 0.89–1.05 g/cm3 after pressing with a compression level between 46.98–63.97%, while the samples in the middle parts increased from 0.70–0.83 g/cm3 to 1.02–1.18 g/cm3 with the compression level of 32.92–41.50%. These results were slightly higher than that of the upper parts, which was between 0.91–0.98 g/cm3. The recovery of set decreased and the weight loss increased with increasing temperature and steam treatment time. Fixation of compressive deformation could be achieved at 160°C within 60 minutes. The bottom parts of samples experienced a slightly greater weight loss compared to the middle parts, i.e. 8.38% and 7.49%, respectively. The anatomical structure of bamboo tended to deform during densification process. Furthermore, the steam treatments affected the colour of densified bamboo which became darker. From this experiment, it can be concluded that the manufacture of laminated bamboo from bamboo slats can be uniformed in strength by equalizing the density at the bottom and middle with the upper parts through the densification technique. However, further research should be conducted to know the delamination and shear strength of the bamboo lamination.

Polymer light-emitting diodes (PLEDs) are generally fabricated using the wet process. Although it is difficult to stack multiple layers by the wet process, it is compatible with the lamination proc...

The mechanical properties of sandwich panels with a polyurethane core and fiberglass face layers produced by a continuous lamination process have been studied. Tensile, compression and shear tests were performed on isolated face layer materials. Using a nonlinear finite-element model, the mechanical behavior of the sandwich panels in flatwise compression, edgewise compression, and bending was simulated, and a good agreement with experiments was found to exist.

Nowadays, autoclaves are widely used for industrial applications such as composite material production, laminated glass production and rubber industry. An autoclave is pressurized and heated up according to its special recipes, which are prepared by considering the technical specifications of the interlayer material and the types and thickness of the glass sheets. During the entire laminated glass production period, the gasket on the autoclave door provides sealing and it must not damage the steady air circulation inside the autoclave. In the present study, the sealing of a glass lamination autoclave was investigated numerically. In order to perform finite-element analysis (FEA), a simplified finite-element model was created by considering both the gaps between the autoclave door and its housing and the geometry of the gasket. In general, hyper-elasticity-based gasket materials were used for glass laminating autoclaves. A Mooney–Rivlin hyper-elastic material model was used for this study. In this study, nine different gasket geometries were designed and finite-element method (FEM) analyses of the gaskets were carried out by using the Ansys Workbench software. FEM analyses were performed at 13 bar operating pressure. The results were compared in terms of deformation of the gaskets and von Mises equivalent stress. The most suitable gasket geometry was determined according to the simulation and FEA results.

S-glass-fiber-reinforced plastic layered composites were prepared by the vacuum-assisted resin transfer molding, and their mechanical properties in relation to different layering types were studied. The effects of layering type and off-axis angle on the tensile and flexural strengths of the composites were clarified. In addition, variations in the intelaminar shear strength and bearing strength by bolted joints as functions of off-axis angle were investigated. Results indicated that the tensile and flexural strengths of the S-glass fiber composites with the 0° lamination were more sensitive to the off-axis angle than those with the 0°/90° orthogonal lamination.

In this paper, an experimental procedure is presented in order to handle magnetic measurements under uniaxial tensile stress reaching the plastic domain. The main advantage of the proposed procedure is that it does not require an additional magnetic core to close the magnetic flux path through the studied sample. The flux flows only in the sample and no parasitic airgaps are introduced, which avoids the use of H-coil to evaluate the magnetic field, often very sensitive and not easy to calibrate. A specimen of non-oriented (NO) FeSi (1.3%) sheet (M330-35A) is characterized under uniaxial tensile stress. In order to validate the proposed procedure, a comparison with the single sheet tester procedure is carried out. The results obtained by the two procedures are in a good agreement. Moreover, to illustrate the possibilities offered by the proposed procedure, we confirm some results met in the literature. We show that positive plastic strain leads to significant degradation of magnetic behavior. An applied tensile stress on a virgin (un-strained) sample leads to a magnetic behavior degradation. Whereas, on a pre-strained sample, an applied tensile stress results in reducing the deterioration caused by the plastic strain until a stress value called optimum. Above this threshold, the magnetic behavior re-deteriorates progressively.

To meet the requirements of today’s fast-growing Li-ion battery market, cell production depends on cheap, fast and reliable methods. Lamination of electrodes and separators can accelerate the time-consuming stacking step in pouch cell assembly, reduce scrap rate and enhance battery performance. However, few laminable separators are available on the market so far. This study introduces electrospinning as a well-suited technique to apply thin functional polymer layers to common battery separator types, enabling lamination. The method is shown to be particularly appropriate for temperature resistant ceramic separators, for which stable interfaces between separator and electrodes were formed and capacity fading during 600 fast charging cycles was reduced by 44%. In addition, a straightforward approach to apply the method to other types of separators is presented, including separator characterization, coating polymer selection, mechanical tests on intermediates and electrochemical validation in pouch cells. The concept was successfully used for the modification of a polyethylene separator, to which a novel fluoroelastomer was applied. The stability of the electrode/separator interface depends on the polymer mass loading, lamination temperature and lamination pressure, whereas poorly selected lamination conditions may cause damage on the separator. Appropriate adhesion force of 8.3 N/m could be achieved using a polymer loading as low as 0.25 g/m2. In case separator properties, coating polymer, morphology of the fibrous coating and lamination conditions are well adjusted to each other, the implementation of electrospinning and lamination allows for faster, more flexible and robust pouch cell production at comparable or better electrochemical cell behaviour.

A review on optimization of adhesively bonded spar-wingskin joint (SWJ) of laminated fiber reinforced polymer (FRP) composites subjected to pull-off load is presented in this article using three-dimensional finite element analysis. Von Mises stress components have been computed across the width of joint at different interfaces viz. load coupler-spar, and load coupler-wingskin interfaces. Further, the weight of SWJ structure is considered as the objective function which needs to be minimized for optimization. In the first step, the material and lamination scheme of the FRP composite materials used for SWJ are optimized, and, in the second step, the geometrical parameters have been optimized on the basis of minimum von Mises stress and weight. Further, the effects of the material, lamination scheme, and geometrical parameters on the von Mises stress and weight have been validated using the Analysis of Variance (ANOVA) approach as prescribed by the Taguchi method. The results show that the material and spar thickness are the most significant factors influencing von Mises stress. The weight analysis reveals that there is a significant effect of change in material and wingskin thickness on SWJ performance. Suitable design recommendations have been made for SWJ in terms of material, lamination scheme and geometrical parameters.

The initial idea of this research is to exploit the abundance of wood waste material in the form of coins which have almost the same size and thickness. This waste comes from the rest of the production of glass bottled water. One way to achieve this goal is by using horizontal and vertical lamination techniques with the addition of a turning process with the aim of being able to form and produce functions. Another goal is to apply the waste coin arrangement as a functional and decorative product design material. The design of this product with waste is used as a model for empowering the creative industry of the local crafts-producing community where glass mineral water is located in Sambeng Village, Kasiman District, Bojonegoro Regency, East Java. The design method used is the Design Thinking method. The output produced is in the form of functional and decorative product designs, such as stools, wall clocks, frames, candle holders, egg holders, menu boards, and placemats.

Jelly-roll (JR) processed wires using metal thin foils as starting materials have excellent cold workability and drawability. We have successfully fabricated Nb/Al composite mono-core wires having 50 μm in outer diameter and over 400 meters in length. Furthermore, some of the wires were additionally drawn to 30 μm in outer diameter. It is known that the critical current density ( J c) of Nb3Al synthesized by low-temperature diffusion reactions increases with decreasing the diffusion distance between Nb and Al. In this study, we have confirmed that J c would increase with decreasing the wire diameter, and the maximum J c has been obtained on Nb3Al wires with 30 μm in diameter. In addition, a 7-wire round cable has also been demonstrated using 80 μm diameter wire, with an I c 7 times the I c of a single wire. A transport current test was performed for the cable sample simulating W&R and R&W processes using a 50 mm diameter G10 holder. There were no differences between the I c and the n-values in the W&R and R&W processes. Moreover, as a feasibility study, a 3rd bundle Rutherford cable has been successfully fabricated using 3,108 pure copper wires 50 μm in diameter.

The alumina slurry with high solid content was prepared, and a rapid lamination route for fabricate the Nextel™ 610 fiber reinforced alumina composite was proposed in this work. The microstructure and mechanical properties of the as-received all-oxide composite were investigated by a series of techniques. The shrinkage cracks in matrix were reduced, while porous structure in composite was maintained. The N610/alumina composite has weak matrix and weak interface, as the Young’s modulus of the alumina matrix and the interfacial shear strength of the composite are 140.8±2.5GPa and 129.1±14.6MPa. The mechanical properties of the composite are much higher than lots of oxide/oxide composites, given its flexural strength, interlaminar shear strength and the fracture toughness are 398.4±5.7MPa、27.0±0.5MPa and 14.1±0.9MPa·m1/2, respectively. The flexural strength of the virgin composite keep stable at 25–1050 °C, while dramatically decrease at 1100–1200 °C.

The ongoing miniaturization and functional heterogeneity in electronics packaging are pushing the demand for advanced substrate technologies. Highly integrated, advanced multi-chip packaging solutions combine application, logic and computing dies with memory or components for power management in a single package. A solution to achieve low fabrication costs is the close embedding of thin dies in IC Substrates based on large formats (600 x 600 mm²), known from PCB fabrication. In a consortium of partners from industry and research advanced technologies for Panel Level Packaging (PLP) are developed. This paper will show the development of 5µm L/S RDL routing density and chips with 50µm bump pitch. Here, the 6x6 mm² dies are symmetrically embedded into an organic laminate matrix. A PCB core (100µm thickness) with very low coefficient of thermal expansion (CTE) containing laser cut cavities is used, acting as a frame layer. Besides mechanical and handling stability, the usage of such a frame offers the advantage of pre-integrating additional features like local fiducials, through vias or power lines by conventional PCB processes. Within that frame, the dies are embedded by lamination of an organic build-up film with 25µm thickness equal to bump height. The chip contacts are then opened without the need of any micro via formation. Here a strong focus is set on RIE etching of the polymer material. Highly accurate measurement of the real die position is essential for the following processing. The formation of the redistribution layer (RDL) is done in a semi-additive process (SAP) utilizing sputtering technique and direct imaging (LDI). To achieve the fine pitch demands, an adaptive imaging process is applied. Therefore, a newly developed LDI machine is used to write structures in a 7µm photoresist. This exposure also combines the measurement data of the real die position and the adaption of the exposure artwork, in order to achieve highest registration quality.

Purpose The use of a gas metal arc welding-based weld-deposition, referred to as wire-direct energy deposition or wire-arc additive manufacturing, is one of the notable additive manufacturing methods for producing metallic components at high deposition rates. In this method, the near-net shape is manufactured through layer-by-layer weld-deposition on a substrate. However, as a result of this sequential weld-deposition, different layers are subjected to different types of thermal cycles and partial re-melting. The resulting microstructural evolution of the material may not be uniform. Hence, the purpose of this study is to assess microstructure variation along with the lamination direction (or build direction). Design/methodology/approach The study was carried out for two different boundary conditions, namely, isolated condition and cooled condition. The microstructural evolution across the layers is hypothesized based on experimental assessment; this included microhardness, scanning electron microscopy imaging and electron backscatter diffraction analysis. These conditions subsequently collaborated with the help of thermal modeling of the process. Findings During a new layer deposition, the previous layer also is subject to re-melt. While the newly added layer undergoes rapid cooling through a combination of convection, conduction and radiation losses, the penultimate layer, sees a slower cooling curve due to its smaller exposure area. This behavior of rapid-solidification and subsequent re-melting and re-solidification is a progressing phenomenon across the layers and the bulk of the layers have uniform grains due to this remelt-re-solidification phenomenon. Research limitations/implications This paper studies the microstructure variation along with the build direction for thin-walled components fabricated through weld-deposition. This study would be helpful in addressing the issue of anisotropy resulting from the distinctive thermal history of each layer in the overall theme of metal additive manufacturing. Originality/value The unique aspect of this paper is the postulation of a generic hypothesis, based on experimental findings and supported by thermal modeling of the process, for remelt-re-solidification phenomenon followed by temperature raising/lowering repetitively in every layer deposition across the layers. This is implemented for different types of base plate conditions, revealing the role of boundary conditions on the microstructure evolution.

New interconnect schemes that replace metallic solders with electrically conductive adhesives (ECA) are appearing in recent embodiments of crystalline silicon photovoltaic (PV) modules. Recently, potential ECA interconnect failure modes were identified and characterized, which included cohesive cracking and debonding of the adhesive joint. In this work, we elucidate on how and to what extent the driving force for ECA degradation develops in shingled cell modules. We have employed a multiscale modeling approach, using the finite-element method, to accurately predict the driving force for both accelerated stress testing conditions and on-sun exposure of PV modules. When we compare our driving force predictions for a generic PV module with the experimentally characterized fracture properties of a candidate ECA, we found that interconnect failure of only poor quality or otherwise damaged joints is likely to occur. Furthermore, we show how a 2-D submodel can efficiently predict limits for the debond driving forces without needing to employ the multiscale modeling approach.

The objective of this study is to clarify the effect of resin lamination on the tensile strength characteristics of SUS304 stainless steel thin films. We conducted tensile and stepwise tensile tests using several types of specimens prepared with 20-μm- and 40-μm-thick SUS304 films, 25-μm-thick polypropylene (PP) film, and 6-μm-thick polyethylene terephthalate (PET) film. Their macroscopic and microscopic tensile deformation behaviors were observed using an optical microscope and a reflection-configured digital holographic microscope, respectively. As a result, laminating the PP or PET films onto the SUS film did not significantly change the macroscopic and microscopic strain changes against the tensile load or microscopic surface changes in the low-strain region. Laminating the PET film onto the SUS film did not reduce the fracture strain, whereas laminating the PP film onto the SUS film did reduce it. One of the reasons may be that burrs formed on the side surface of the PP/SUS laminate. Polishing the side surface of the PP/SUS laminate may suppress the reduction in its fracture strain. The reduction of the fracture strain due to the PP lamination in the 20 μm thick SUS film was larger than that of the 40-μm-thick SUS film. In thin SUS films, small stress concentrators that have almost no effect on macroscopic and microscopic deformation might significantly reduce the fracture strain.

This paper describes a relatively simple closed form formula for predicting the strength of glulam assemblies in bending about the major axis based on statistical engineering mechanics using the tension strength of finger jointed of bonded lamination pairs. It has been calibrated against the strengths of full-size glulam beams ranging in depths from 150 mm to 1200 mm over spans of 2.7 m up to 19.5 m. Comparisons are made at both the mean strength and 5th percentile strength levels with the latter drawing attention to the fact that all test series invariably involve observation of minimum values that means the statistical distributions are invariably truncated. For Weibull distributions, this has an impact on the shape factor and, therefore, the local coefficient of variation of the lower tail, which plays an important role in size effects in glulam and potentially has wider implications.

Embedded resistors in printed circuit boards (PCBs) are fabricated to provide high integration, improved electrical performance, and reduced parasitic capacitance and inductance in the high-frequency and high-speed environment. At present, the embedded resistance errors caused by etching metal film accuracy are generally more than 20%. In this work, real-time monitoring technology is developed to precisely control the resistance of electroless-plated embedded resistors. During the deposition process, the resistances of embedded resistors are monitored until reaching the targeted resistance, realizing the very ideal resistance error lower than 10%. Arbitrary shapes including serpentine and zigzag structures of embedded resistors are attempted to validate the practical capability of this approach. Reliability Characterization experiments such as high-temperature and high-pressure lamination, thermal shock and thermal cycles confirm the thermal and mechanical stability. It is demonstrated that the embedded resistors through real-time monitored electroless plating have tremendous potential in the manufacture of high-frequency and high-speed PCBs.

This article develops a multi-scale model order reduction (MOR) method including both material and machine scale MOR. The material-scale MOR homogenizes the eddy-current (EC) field in laminated cores using the Legendre expansion of magnetic induction along the stacking direction within each steel sheet. The machine-scale MOR represents the EC field in electromagnetic devices with their equivalent Cauer ladder network (CLN). The former MOR is built into the latter by applying the CLN procedure to the homogenized EC field equation.

In this article, a finite element (FE) modeling of the punching effect on the magnetic properties of electrical steel sheet is carried out. For that, the modified anhysteretic Sablik model is applied together with the plastic strain distribution obtained from a punching process simulation performed using the software ABAQUS. First, a synchronous electrical machine is simulated including the effect of the punching process, and it shows the degradation of the magnetic flux density at the lamination edges and an increase of the iron losses. Then, results obtained from the magneto-mechanical simulation are investigated in terms of the method used to implement the plastic strain distribution in the FE computation. Two examples have been investigated: a square steel sheet and a tooth of an electrical machine.

Metal stamping is a cold-forming process that uses dies and stamping presses to convert sheet metal into desired geometries. The metal stamping process leaves residues on stamped components such as releasing agents, metal shavings, and other contaminants as they exit the press. These impurities hinder the functionality of the components. Therefore, they are required to be eliminated before the stamped sheets are assembled on the production line. Contaminant metal particles on the surfaces hinder the functionality of the components and eventually promote mechanical wear between the moving parts. It is consequently difficult to eradicate contaminants, as their adhesion is inevitable, the contaminants being at a range of a few micrometres to sub-micrometres. The myriad shape configuration of the present metallic and non-metallic contaminants posed a challenge to reaching the cleanliness standards desired by the quality of the product. We aim to develop an automated decontamination process to improve product quality, with an optimized production cycle, and cost-effectiveness. Fibres non-metallic particles are also necessarily rid from the surfaces of the component. In this study, the prime focus is on metallic contaminants, excluding the non-metallic fibrous contaminants that were present. Three viable techniques are opted for based on their feasibility on production line incorporation potential. Namely, Mechanical vibration, Pressurized air-blowing, and Ultrasonic cleaning. However, to achieve the greatest possible outcome, the three different techniques are weighed against each other.

Günümüzde koruyucu giysiler üzerinde birçok çalışma yapılmaktadır. Son dönemlerde soğuk iklim koruyucu kıyafetlerdeki çalışmalar yoğunlaşmış olmakla birlikte gerek ekonomik sebepler gerek ise teknik sorunlar sebebi ile istenilen boyutta başarı elde edilememiştir. Ülkemizde ve dünyada son zamanlarda dağcıların, orduda görevli askerlerin hipotermi sonucu hayatlarını kaybettikleri olaylar gerçekleşmiştir. Bu sebepten dolayı çalışmada askeri tekstillerden, dağcılık kıyafetlerine kadar birçok alanda kullanım alanı bulunan soğuk iklim kıyafetlerinin mevcut yöntemlerden farklı üretim yöntemleri kullanılarak geliştirilmesi amaçlanmıştır. Gerçekleştirilen çalışma kapsamında tasarlanan ve üretilen ürünlerin özellikleri ergonomik yönden ve performans açısından incelenmiş ve mevcutta kullanılan soğuk iklim kıyafetleri ile kıyaslanmıştır. Çalışmada 3 farklı yöntem kullanılarak 6 farklı çeşit ürün elde edilmiştir. İlk yöntemde boncuk elyaf polyester, mikrojel polyester ve hollowelyaf farklı oranlarda dolgu malzemesi olarak kullanılmıştır. İkinci yöntemde çevreci yaklaşımlar hedeflenmiş ve atık kumaşların değerlendirilmesi amaçlanmıştır. Bu amaçla dikimevlerinde askeri kullanım amacı ile üretilen kıyafetlerin ve konfeksiyon aşamasında çıkan atık kırpıntı kumaşların geri dönüştürülmesi ile havlı yüzeyde bir kumaş elde edilmiştir. Bu yüzey ana malzeme ile birleştirilerek lamineli kumaş yüzeyi elde edilmiştir. Üçüncü yöntemde ise karbon elyaftan elde edilen dokusuz yüzey kumaş ara katman olarak Polyester bir film ile birleştirilerek yanmazlık ve soğuk iklim özelliklerinin bir arada elde edilmesi planlanan bir tasarım yapılmıştır. Farklı alanlarda kullanılması planlanan ve üretilen altı farklı soğuk iklim kıyafetlerinin performansları Türk Silahlı Kuvvetleri Kara Kuvvetleri Komutanlığı’nda şu anda kullanılmakta olan konvensiyonel metotlarla elde edilen kıyafetlerin performansları ile kıyaslanmış ve yapılan testler doğrultusunda, mevcutta kullanılan soğuk iklim kıyafetlerine muadil olarak aynı ve/veya daha iyi fonksiyonel etkilere, farklı üretim teknikleri kullanılarak ulaşılabileceği gözlemlenmiştir. Today, many studies are being conducted on protective clothing. Although the work on cold climate protective clothing has been intensified recently, the desired size has not been achieved due to both economic reasonsand technical problems. Recently, incident shave occurred in our country and around the world in which climbers and soldier serving in the army have lostheirlives as a result of hypothermia. For this reason, in the study, it is aimed to develop cold climate clothing that has been used in many fields, from military textiles to mountaineering clothing,using different production methods than existing methods. The characteristics of the products designed and manufactured within the scope of the study were examined ergonomically and in terms of performance and compared with the coldclimate clothing currently used. In the study, 6 different kinds of products were obtaine dusing 3 different methods. In the first method, bead fiber polyester, microgel polyester and hollow fiber were used as filler materials in different proportions. In the second method, environment alapproaches were aimed and it was aimed to evaluate waste fabrics. For this purpose, a fabric was obtained on the pile surface by recycling the clothes produced for military use in sewing houses and the waste clipping fabrics produced during the garment stage. This surface was combined with the main material to obtain a laminated fabric surface. The third method, a carbon fiber nonwoven fabric layer film obtained from the characteristics of fire and cold climates Polyester combined with a design is made of which is planned to be obtained. Planned to be used in differentareas of the Turkish Armed Forces and the performance of cold climate produced six different clothing in command of the land forces of the out fitobtained by conventional methods that are currently being used and the test shave been compared with the performance. It has been observed that different production techniques can be used in these clothes.

In this work, the effect of cold deformation prior to annealing treatment on the microstructure and magnetic hysteresis energy losses in a low carbon grain non-oriented semi-processed electrical steel with 0.60 mm thickness was investigated. The samples were subjected to different percentages of deformation, in a range of 5–20% reduction and annealed at temperatures between 650 and 950 °C for 60 min, these were characterized by Optical Microscopy. Meanwhile the energy losses were calculated from the magnetic hysteresis loops using a Vibrating Sample Magnetometer. The experimental results showed that cold deformation increases energy losses by 50% when the steel is deformed 20%, due to microstructural defects that are introduced to the material during deformation. The presence of the microstructural defects was verified through measurements of Full Width at Half Maximum by means of X-ray diffraction. On the other hand, it was observed that annealing at temperatures below Ac1 causes only small changes in the microstructure of the steel, however, it promotes the recovery of magnetic properties by 50% with respect to the deformed material. In contrast, when the material is annealed between Ac1 and Ac3(α+γ) magnetic properties are recovered ~33% with respect to the initial state and, at values higher than 65% compared to the state of greatest deformation (20%), as a result of both microstructural modification and the evolution of the grain size experienced by the material.

Human doublecortin (DCX) mutations are associated with severe brain malformations leading to aberrant neuron positioning (heterotopia), intellectual disability and epilepsy. DCX is a microtubule-associated protein which plays a key role during neurodevelopment in neuronal migration and differentiation. Dcx knockout (KO) mice show disorganized hippocampal pyramidal neurons. The CA2/CA3 pyramidal cell layer is present as two abnormal layers and disorganized CA3 KO pyramidal neurons are also more excitable than wild-type (WT) cells. To further identify abnormalities, we characterized Dcx KO hippocampal neurons at subcellular, molecular and ultrastructural levels. Severe defects were observed in mitochondria, affecting number and distribution. Also, the Golgi apparatus was visibly abnormal, increased in volume and abnormally organized. Transcriptome analyses from laser microdissected hippocampal tissue at postnatal day 60 (P60) highlighted organelle abnormalities. Ultrastructural studies of CA3 cells performed in P60 (young adult) and > 9 months (mature) tissue showed that organelle defects are persistent throughout life. Locomotor activity and fear memory of young and mature adults were also abnormal: Dcx KO mice consistently performed less well than WT littermates, with defects becoming more severe with age. Thus, we show that disruption of a neurodevelopmentally-regulated gene can lead to permanent organelle anomalies contributing to abnormal adult behavior. ispartof: NEUROBIOLOGY OF DISEASE vol:168 ispartof: location:United States status: published

In this research, cellulose acetate/blends of polyvinyl alcohol and polyacrylic acid (CA/PA) bilayer porous membrane was prepared by electrospinning and esterification. Then the developed membrane was laminated onto polyester fabrics to examine their practical applications in the textile area. Investigations for surface morphology, the water content distribution and the moisture absorption were done in detail to examine the unidirectional moisture transport performance of the CA/PA bilayer porous membrane and the laminated fabrics. The results illustrated that when the electrospinning arrangement time was PA-CA=6h-4h, the lamination pressure 2 MPa and the lamination time 35 seconds, the laminated fabric had the best performance. At this time, the composite laminated fabric exhibited a value for one-way moisture transport capability (R) of 960.76 % with overall moisture management capacity (OMMC) performance of 0.84 %. Additionally, the moisture absorption and perspiration of the laminated fabric can reach level 5.

The laser micro-spot welding process was studied to implement a sheet lamination process-based methodology for the fabrication of austenitic stainless steel scaffolds. AISI 302 sheets with a thickness of 254 μm were laser cut and laser welded. Experimental tests were carried out with different values of average laser power (i.e., 180, 200, and 220 W) and different exposure times (25, 50, 75, 100, 125 ms). The micro-spot welds were visually inspected according to the ISO 13919-1 Class B requirements. Spot welds were qualitatively characterized, and weld dimensions were measured (i.e., penetration depth, top, middle, and bottom width and the heat-affected zone (HAZ)) to identify the cross-sectional shape. Furthermore, process efficiencies (i.e., coupling, melting, and process) were studied. A seam welding model was adapted to calculate the required exposure time and was used to obtain a micro-spot weld to accomplish the quality requirements of the scaffold. A scaffold prototype was designed and manufactured using the selected parameters by experimental trials and using the mathematical model (i.e., a laser power of 220 W and an exposure time of 45 ms).

Summary Despite heterogeneity across the six layers of the mammalian cortex, all excitatory neurons are generated from a single founder population of neuroepithelial stem cells. However, how these progenitors alter their layer competence over time remains unknown. Here, we used human embryonic stem cell-derived cortical progenitors to examine the role of fibroblast growth factor (FGF) and Notch signaling in influencing cell fate, assessing their impact on progenitor phenotype, cell-cycle kinetics, and layer specificity. Forced early cell-cycle exit, via Notch inhibition, caused rapid, near-exclusive generation of deep-layer VI neurons. In contrast, prolonged FGF2 promoted proliferation and maintained progenitor identity, delaying laminar progression via MAPK-dependent mechanisms. Inhibiting MAPK extended cell-cycle length and led to generation of layer-V CTIP2+ neurons by repressing alternative laminar fates. Taken together, FGF/MAPK regulates the proliferative/neurogenic balance in deep-layer corticogenesis and provides a resource for generating layer-specific neurons for studying development and disease., Highlights • FGF/MAPK regulates the proliferative/neurogenic balance in deep-layer corticogenesis • FGF/MAPK signaling maintains the progenitor pool and generates layer-VI neurons • MAPK inhibition prolongs cell cycle to yield layer-V neurons, repressing other fates • Protocols to generate layer-specific cortical neurons to study development and disease, Despite heterogeneity across human cortical layers, all excitatory neurons evolve from a single founder stem cell population. How these progenitors alter layer competence over time is unknown. Using human pluripotent stem cell-derived cortical progenitors, we demonstrate that FGF/MAPK signaling regulates the proliferative/neurogenic balance in deep-layer corticogenesis. Modulating FGF/MAPK enables generation of layer-specific neurons to study development and disease.

Type III vessels are used to store gases at high pressure and, for efficient use, should be as light as possible without compromising stability. However, since the fiber composite layer has a directional property, it causes different properties depending on the order of lamination and the direction of the layer, and it is necessary to evaluate various and complex variables because both the low and high lamination angles are used in the manufacturing process. Therefore, this study evaluated the composite material layer of type III high pressure storage vessels in a single layer pattern and a composite pattern, and evaluated the effects of the inherent characteristics of each angle and the increase or decrease in the stacking angle on the strength performance of the storage vessel. As a result of analysis, it was confirmed that the change of angle not only affects the strength performance, but also affects the location of storage vessel such as domes and cylinders. In addition, in the most optimized pattern, the stress of 79 MPa in the fiber direction and 20.35 MPa in the fiber orthogonal direction could be reduced.

The stochastic investigation of fracture response of centrally cracked symmetric angle ply laminated composite plates subjected to different types of biaxially applied stresses by implementing stochastic extended finite element method (SXFEM) is carried out. The second-order perturbation technique is used in the framework of well-established extended finite element method to obtain the mean and coefficient of variance of mixed-mode stress intensity factors by random change in input parameters. The various system properties such as material elastic properties, lamination angle, loading, crack parameters like crack length and crack angle are modelled as independent, and they combine uncorrelated and correlated input random Gaussian variables. Typical numerical results are presented to examine the effect of various levels of uncertainties in biaxial load factors, fibre angle, crack eccentricity in X and/or Y direction, crack angles and crack lengths. The results obtained using SXFEM approach are compared with the results available in the published literature, and by performing Monte Carlo simulations, an excellent agreement is seen.

Flexible copper clad laminate has been used to fabricate flexible electronics such as bio-inspired tactile sensor, microfluidics-based sensor, and flexible printed circuits board. Herein, the effects of thermal property difference between the component layers on the residual interfacial deformation in a flexible copper clad laminate occurring during roll-to-roll composite film manufacturing were analyzed. The thermal behaviors of polyimide film and copper meshes in the laminate were examined, and it was found that differences of the coefficient of thermal expansion and elastic modulus between the two components could cause the residual deformation in the laminate. The three factors affecting the residual strain due to the thermal characteristic difference, i.e., temperature and pressure of the lamination roll and web tension, were selected in the controllable operating conditions in a roll-to-roll lamination process. Mathematical models to estimate the elastic and thermal residual strains according to the factors were developed and experimentally verified. Finally, the effects of the three factors on the residual strain in the laminate were determined using the developed model. In this study, we demonstrate that, in the lamination process, the thermal strain of the laminate component materials after thermal cycling generates a significant residual deformation, which causes defects in the flexible copper clad laminate. The developed model can be used to accurately estimate the residual elastic and thermal residual strains occurring during the roll-to-roll manufacturing according to the process conditions.

A new process of activating sizing film free (removed sizing) carbon fiber (SFF-CF) mats directly with electron beam irradiation (EBI) under oxygen-rich nitrogen gas prior to lamination assembly and hot-press was found to increase bending strength of CFRTP (CF reinforced thermoplastic polypropylene (PP)) interlayered composite composed of 3 SFF-CF mats between 4 PP sheets, [PP]4[SFF-CF]3. The hot-press fabrication was performed under 4.0 MPa at 473 K for 1 min. Experimental results showed optimal condition of 0.22 MGy-EBI under 2,000 ppm-O2-rich, protective N2 atmosphere improved bending strength, σb at all accumulative probabilities, Pf over that of untreated. This could be explained by maximum number of the strong covalent bonds of CF:C:C:PP and oxygen assisted CF:C:O:C:PP bonds adhering bare SFF-CF surface to PP, instead of the weak intermolecular bonding of CF(H2O, N2, O2)PP of untreated. The optimal concentration of O2 molecules together with the EBI probably purified the SFF-CF surface simultaneously generating dangling bonds, which already naturally exist in SFF-CF as evidenced by the highest intensity ESR peak whose inflection point was at B = 323 mT. This, along with attaching O groups to the SFF-CF surface can explain the increased SFF-CF to PP adhesion sites and bending strength increase. Fracture analysis showed the optimum condition prevented ply delamination and reduced damage area along sample length appearing to increase cohesion between the difficult to adhere thermoplastic PP and SFF-CF plies to take on higher loads. Although bending strength was increased, carefulness is always highly recommended when investigating unsized CF composites.