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Symmetric double-sided electrostatic actuators in push-pull configuration are particularly suitable for linear actuation with low harmonic distortion. However, their motion still is largely determined by pull-in instabilities that are sensitive to geometry variations. A considerable simulation effort is therefore required when assessing manufacturing tolerances during the design process or determining the optimal operating point. Recently, an accurate method was demonstrated, allowing for the numerically inexpensive and experimentally non-destructive extraction of the full quasi-static performance of a clamped-free beam-like electrostatic micro-mechanical actuator with complex 3D design. The key step was to determine the voltage scaling related to the pull-in voltage based on data collected far away from pull-in conditions. This relates a dimensionless ansatz to the physical input voltages as well as the output like e.g. the actuator's tip deflection. For the chosen approach, however, the relationship between the model and the geometry parameters is unknown. In this paper we propose a method to enable quantifying the impact of geometry parameter variations. In particular, we adapt the model equation for the case of symmetry-breaking tolerances on the basis of few FEM-simulations. The quasi-static pull-in instability, as well as the nonlinear deflection, are consistently reproduced over the full range of relevant combinations of signal and bias voltages. Our analysis was developed in the context of a specific electro-acoustic transducer. However, we find indications that the underlying method is in fact applicable to a much broader range of micro-mechanical actuators. [ABSTRACT FROM AUTHOR]

In this paper is presented a two-dimension analytical model for linear permanent magnet inner armature double-sided synchronous motors (LPMIADSSMs). The flux density in all areas of the proposed machine is calculated based on the sub-domain method. According to this method, the machine areas are divided into eleven sub-regions such as first external, first mover, first PM, first air gap, first winding, stator, second winding, second air gap, second PM, second external and second mover, which sign as FE, FR, FP, FAG, FW, S, SW, SAG, SP, SE and SR. To find the flux density equations, it is mandatory to solve the extracted Maxwell equations and apply the boundary conditions between each two sub-regions, which lead to find the unknown coefficients for flux density in each sub-region. In addition, the influences of magnetization patterns, i.e., parallel, ideal Hal Bach, 2-segment Halbach and bar magnet in the shifting direction of the flux distribution and armature reaction (AR), are investigated. To validate the obtained results, the proposed model results are compared with those obtained from finite element method (FEM) and Maxwell software. [ABSTRACT FROM AUTHOR]

A high-efficiency system was designed as an improvement in conventional reel-to-reel system for ion beam-assisted deposition (IBAD) and homo-epitaxy of double-sided biaxially textured MgO thin films. This system enables Hastelloy tape to flip automatically and go through the deposition area twice in order to deposit MgO on its both sides. With this system, the output of double-sided IBAD-MgO is elevated to be 30 m·h−1. A 30-m tapes with 10-nm-thick double-sided biaxially textured MgO thin films was successfully made. X-ray diffraction (XRD) and atomic force microscope (AFM) show identical quality of MgO thin films on both sides. The yield full width at half maximum values of out-of-plane texture and in-plane texture on both sides are approximately 3.1° and 5.3°, respectively. Moreover, the influence of ion beam flux and deposition rate on the texture of thin film was investigated. A process window in which biaxial texture can be obtained is found for large-scale production. [ABSTRACT FROM AUTHOR]

The double-sided tubular linear machine (DSTLM) has a more compact structure than general single-sided motors, resulting in a higher power density, typically at the cost of a higher cogging force. To reduce this aspect and make it more suitable for applications in wave energy conversion systems or elevator driver systems, a new tooth-cutting topology is proposed in this article. The Schwarz–Christoffel mapping method is used to model and analyze the magnetic field and cogging force of the DSTLM. Based on the analytical model and the relationships between the cutting dimensions and the force performances, optimization is carried out by using a differential evolution algorithm. The optimization and the experiment results show that the proposed tooth-cutting topology can effectively reduce the cogging force at the small cost of weakening average thrust. [ABSTRACT FROM AUTHOR]

This paper is devoted to developing the regularity results of the true (classic) solution to the homogeneous BVP of double-sided fractional diffusion advection reaction equation with variable coefficients on the bounded interval. This topic has been controversial in modelling in recent years, especially on the regularity issue. We use a different strategy of raising regularity of the weak solution and prove that, under suitable conditions, the true solution exists and can be represented in the form of fractional integration; furthermore, we show that usually this integral representation cannot be further improved even with smooth coefficients and right-hand side function in the equation. And we find the precise bound for this integral representation to hold, which measures the "best" regularity guaranteed and is in sharp contrast to the case of integer-order elliptic PDEs. [ABSTRACT FROM AUTHOR]

This paper investigates the structure of solutions to the BVP of a class of fractional ordinary differential equations involving both fractional derivatives (R-L or Caputo) and fractional Laplacian with variable coefficients. This family of equations generalize the usual fractional diffusion equation and fractional Laplace equation. We provide a deep insight to the structure of the solutions shared by this family of equations. The specific decomposition of the solution is obtained, which consists of the "good" part and the "bad" part that precisely control the regularity and singularity, respectively. Other associated properties of the solution will be characterized as well. [ABSTRACT FROM AUTHOR]

Shot peening is widely used in the aeronautical industry to enhance the fatigue life of the parts and form large, thin, and complex components, such as wing and fuselage skins. Previous research on peen forming simulation has rarely considered the influence of the shot peening sequence on the resulting deformed shape. In particular, the study on the mechanics mechanism of asymmetry in double-sided sequential (un-simultaneous) shot peening is not enough. In this study, therefore, experiments based on symmetrical plane strips (Almen-sized Al7075 strip and Almen strip) show that the final deformation is often asymmetrical with the same shot peening parameters in sequence. As the symmetrical surfaces are peened in sequence, the final bending direction is always consistent with the later shot peening effect. To explain this interesting phenomenon, the double-sided symmetrical sequential shot peening process was simulated by finite element method (FEM). The simulation and experiment results verified the universality of asymmetric deformation in double-sided symmetrical sequential shot peening process. A theory analytical model of the stiffness reduction proposed in this paper was used to explain the asymmetric deformation mechanism, and it is verified by three-point bending tests. Some new results obtained by the experiment and simulation are presented. The influences of the strip thicknesses and shot peening pressures on the asymmetric deformation are discussed in double-sided symmetrical sequential shot peening. [ABSTRACT FROM AUTHOR]

Patients with open abdominal (OA) wounds have a mortality risk of up to 30%, and the resulting disabilities would have profound effects on patients. Here, we present a novel double-sided adhesive tape developed for the management of OA wounds. The tape features an asymmetrical structure and employs an acellular dermal matrix (ADM) with asymmetric wettability as a scaffold. It is constructed by integrating a tissue-adhesive hydrogel composed of polydopamine (pDA), quaternary ammonium chitosan (QCS), and acrylic acid cross-linking onto the bottom side of the ADM. Following surface modification with pDA, the ADM would exhibit characteristics resistant to bacterial adhesion. Furthermore, the presence of a developed hydrogel ensures that the tape not only possesses tissue adhesiveness and noninvasive peelability but also effectively mitigates damage caused by oxidative stress. Besides, the ADM inherits the strength of the skin, imparting high burst pressure tolerance to the tape. Based on these remarkable attributes, we demonstrate that this double-sided (D-S) tape facilitates the repair of OA wounds, mitigates damage to exposed intestinal tubes, and reduces the risk of intestinal fistulae and complications. Additionally, the D-S tape is equally applicable to treating other abdominal injuries, such as gastric perforations. It effectively seals the perforation, promotes injury repair, and prevents the formation of postoperative adhesions. These notable features indicate that the presented double-sided tape holds significant potential value in the biomedical field.

In ultra-high frequency (UHF) band, conventional microwave absorbers are limited in application by their thickness or weight. In order to solve this problem, a novel double-sided and dual-tuned active frequency selective surface (AFSS) absorber for the UHF band is designed and implemented for the first time. The physical mechanism is analyzed by the equivalent circuit method (ECM) and current distribution. Non-coplanar bias circuits of p-i-n diodes and varactors are proposed and achieved by a double-sided structure. The Fano resonance introduced by double-sided structure is analyzed and suppressed. The proposed structure covers an ultrabroadband of 0.4–2.5 GHz (144.8% in fractional bandwidth) below −10 dB by changing the working states. The thickness is only $\lambda _{L}$ /30 in the lowest operating frequency, and the areal density is only 1.54 kg/m2. It is worth mentioning that the structure has good angular sensitivity and can be used to complex targets for low-RCS applications. [ABSTRACT FROM AUTHOR]

Innovative double-sided welding is expected to improve the fatigue resistance of rib-to-deck welded joints of orthotropic steel decks (OSDs). Welding crack-like defects are the crucial issue affecting the fatigue performance of rib-to-deck double-sided welded joints. This study presents a numerical simulation of three-dimensional (3D) mixed mode fatigue crack growth behavior of rib-to-deck double-sided welded joints of OSDs. Maximum tensile stress theory and equivalent stress intensity factor (SIF) were used to simulate mixed mode fatigue cracks growth. The Paris law model was employed to predict the fatigue life. Fatigue cracks of rib-to-deck double-sided welded joints were characterized by the presence of mixed mode cracks of modes I (open), mode II (shear), and mode III (tear), which was dominated by mode I. The equivalent SIF was found to be complex at the growth stage with the maximum value at the two ends of the crack front and the minimum value at the midpoint of the crack front. The crack shape became flatter in the later phase of the crack growth. The fatigue crack surface underwent deflections during crack growth, making the final crack shape exhibiting the characteristic of a spatial curved surface. The initial crack geometry showed a significant impact on the fatigue life. [ABSTRACT FROM AUTHOR]

This study aims to explore the characteristics of platform for social service delivery and the electronic voucher system as an instrument for the delivery. The paper discusses the concept and characteristics of platform and reviews the factors by which firms migrate to platform. Social service e-vouchers are an example of a government platform that pays e-vouchers to consumers and gives them the choice of services. Then it analyzes the case of platform establishment to deliver social services. The demand on welfare services has changed with demographic structure. The change in demand requires innovation in the social service delivery system and adoption of strategies to move to the platform. Factors that enabled the social service delivery platform to build both demand and supply sides include access to employment policies, industrial connection, workforce training, and requirements for social service eligibilities [ABSTRACT FROM AUTHOR]

The capacitance of microsupercapacitors (MSCs) can double if both sides of substrates are used to construct MSCs. Nevertheless, achieving electric connections of MSCs through substrates is a challenge due to the difficulty in precisely positioning each MSC couple that has two of the same MSCs units on two sides. In this work, taking advantage of the synchronous etching on both sides of transparent polyethylene terephthalate substrates by femtosecond laser pulses, a double‐sided configuration is attained with high precision in the alignment of back‐to‐back MSC couples and versatile double‐side MSCs are realized via arbitrary on‐ and through‐substrate connections of MXene MSC units. The MXene double‐side MSC fabricated by the series connection of 12 spiral pattern MXene MSC units with interdigital electrodes of 10 μm width interspace can output a large working voltage of 7.2 V. Additionally, femtosecond laser etching brings the transformation of MXene into titania near‐etched edges with a lateral distance less than 1 µm. Such a small laser‐affected area has little influence on the capacitive performance, which is one of advantages for femtosecond laser over conventional lasers. This research is valuable for one‐step manufacturing of highly integrated MSCs in the field of miniaturized energy storage systems. [ABSTRACT FROM AUTHOR]

Double-sided permanent magnet linear synchronous machine with 120° phase belt toroidal windings (120°-TWDSPMLSM) suffers from large detent force due to the end effect and slot effect. Many existing methods can reduce the detent force of the 120°-TWDSPMLSM effectively. But they also minimize the back electromotive force (back-EMF) and thrust simultaneously. To alleviate this problem, this paper adopts a method of combining slot-shift structure with rearranging the 120° phase belt toroidal windings (120°-TW) to suppress the detent force and improve the back-EMF and thrust of the 120°-TWDSPMLSM simultaneously. First, the slots on the two sides of the primary part are stagger by an optimal distance to reduce the detent force. The models of the detent force, including the end force and cogging force, is established theoretically, and then verified by finite-element analysis (FA). Then, the 120°-TW are rearranged to improve the back-EMF and average thrust. And the electromagnetic characteristics of the 120°-TWDSPMLSM under different shifted distances are analyzed and compared in detail. Finally, the result shows that the detent force of optimized machine is 70.19% lower than that of the original machine, and the thrust fluctuation reduces 19.21%. Besides, the back-EMF of optimized machine is 6.84% lower than that of the original machine, but 31.86 higher than the machine with shifting slots and without rearranging the 120°-TW. Therefore, the optimal method in this paper is available in the detent force reduction and thrust improvement of the 120°-DSPMLSM.

The longitudinal end effect of the double-sided permanent magnet linear synchronous motor (DS-PMLSM) causes a large end force. To overcome this drawback, this paper proposes a novel DS-PMLSM structure, in which the upper or lower primary component is shifted by a certain distance. First, the end-force model of the DS-PMLSM is established, based on which, the influences of the staggered structure on the fundamental and higher order end-force components are analyzed. Following this, the DS-PMLSMs with different slot–pole combinations are divided into four categories, and the design principles of possible winding arrangements are discussed. Furthermore, the staggered structures are applied to four slot–pole combinations, namely 21-, 15-, 20-, and 16-pole/18-slot. The back electromotive forces, detent forces, thrusts, and normal forces of the four combinations are analyzed and compared through the finite-element method. The electromagnetic and output characteristics of the novel DS-PMLSM are also compared with the traditional DS-PMLSM prototype to verify the effect of the proposed structure on suppressing the end force. [ABSTRACT FROM AUTHOR]

Phase-shift or pole-shift method can reduce the detent force of the double-sided permanent magnet linear synchronous motor (DS-PMLSM) dramatically. However, this method causes a decrease in thrust and an increase in normal force simultaneously. To overcome this drawback, a novel slot-shift structure whose slots on the two sides of the primary component are staggered by an optimal distance is proposed in this paper. The models of the detent force including the end force and cogging force is established theoretically, and then verified by finite element analysis. The windings in the upper primary and the lower primary are arranged differently to improve the average thrust. The thrust characteristics of the DS-PMLSM under different shifted distances are analyzed and compared in detail. Furthermore, the primary component employing two kinds of core laminations is proposed to reduce both the dc component and ripple of the normal force. Finally, a DS-PMLSM prototype is tested, and the experimental results are compared with the analytical results to verify the effectiveness of the theoretical and simulation research. [ABSTRACT FROM AUTHOR]

In this paper, two novel double-sided hybrid-excitation flux-reversal linear motors (DSHEFRLM) with the surface (S-) and interior (I-) permanent-magnet(PM) arrangements are proposed and comparatively investigated. The proposed motors feature an asymmetrical double-sided primary configuration which enables the armature and field excitations to be placed separately. Through 2-D finite-element method (FEM), two motor structures with different slot/pole combinations are optimized, and then, the magnetic fields and electromagnetic performances are calculated, including inductances, no-load flux linkage, thrust characteristics, and PM demagnetization capability. By comparison, it is found that S-DSHEFRLMs show larger thrust density while I-DSHEFRLMs exhibit superior flux-adjusting capability. Finally, these predicted results are validated by 3-D FEM. [ABSTRACT FROM AUTHOR]

Traditionally, straggering the primaries of the double-sided permanent magnet linear synchronous motor (DS-PMLSM) is beneficial in helping to reduce the detent force caused by the longitudinal end effect, but leading to a reduction of the average thrust. To overcome this disadvantage, this paper provides a novel DS-PMLSM, which adopts the structure of staggering two primaries and rearranging windings. First, the characteristics of the voltage and detent force are analyzed theoretically and verified by finite element (FEM) simulations. The inductance, thrust, and normal forces are then compared with the traditional DS-PMLSM. Furthermore, the geometrical parameters are optimized to improve the thrust. Finally, one DS-PMLSM prototype is tested. The detent force and back electromotive force tested results verify the effectiveness of the topology proposed in this research. [ABSTRACT FROM AUTHOR]

• A new developed MOCVD system with U-shaped nozzle and planetary turnplate was designed. • Smooth surface morphology double-sided CeO 2 buffer layer was simultaneously deposited on R-plane Al 2 O 3 substrate. • J c of YBCO film deposited on CeO 2 -buffered Al 2 O 3 substrate reaches 2 MA/cm2 at 77 K and 0 T. Double-sided CeO 2 /YBCO films were grown on the double-sided polishing R-plane Al 2 O 3 substrate using MOCVD technology. The effects of deposition parameters of the MOCVD setup on the structural orientation and surface morphology of CeO 2 buffer layers grown on sapphire substrates were investigated. A series of CeO 2 buffer layers were prepared by varying the substrate temperature and oxygen flow rate. The results show that when the substrate temperature is lower than 750 °C and the oxygen flow rate is lower than 400 sccm, CeO 2 films is grown in a mixed (00 l) and (111) orientations, and when the substrate temperature is 750 °C-840 °C and the oxygen flow rate is higher than 400 sccm, the CeO 2 films are grown with a single (001) orientation. When the deposition temperature was 800 °C and the oxygen flow rate was 800 sccm, the CeO 2 buffer layer structure had the best orientation with double-sided ω -scan FWHM of 0.019° and 0.02°; the FWHM of double-sided Ф -scan were 1.8° and 1.7°; the RMS roughness on both sides measured by AFM were 1.28 nm. YBCO films grown on this buffer layer have good c -axis epitaxial orientation, and the test results of the pole figure show an in-plane rotation of 45° between YBCO and CeO 2 lattices. Thus, the obtained YBCO film has a critical current density of 2 MA/cm2, indicating that the films can be prepared to meet the needs of microwave devices using R-plane Al 2 O 3 substrates. [ABSTRACT FROM AUTHOR]

Planar solid oxide fuel cells (SOFCs) have been extensively studied during the past few decades, particularly the anode supported SOFC. In traditional electrode‐supported cells, the mismatch of coefficients of thermal expansion between materials in each layer may give rise to thermal stresses during operation, resulting in micro‐cracks of ultra‐thin electrolytes, which may ultimately lead to operational damages and performance degradation. This work proposes a new symmetric, planar SOFC design based on double‐sided cathodes to offset asymmetry of thermal stresses within the structure. This new design has been applied to prepare an anode‐supported SOFC that maintains integrity after two complete redox cycles. Its anti‐fracture load is 20 times stronger than that of traditional ultra‐thin cells, and its electrochemical performance is close to that of traditional large‐scale, ultra‐thin cells. These properties are promising for application under harsh operational environments. Nice structural design for SOFC! A new structure of solid oxide fuel cells is developed, which shows higher anti‐fracture strength and redox stability than traditional solid oxide fuel cells. SEM indicates that this new structural cell can easily obtain dense YSZ and GDC layer. The new structure is suitable for applications under certain extremely environments. [ABSTRACT FROM AUTHOR]

OTT streaming services have been restructuring the global multimedia industry, and there have been strategic actions and reactions among OTT players and traditional pay-TV platforms. This study found that Pricing and Content investments are key factors affecting market share and subscribership in global OTT markets, and M&As have positive effects on the two performance measures, although with less statistical confidence. OTT-specialized firms in the UK, Germany, France, Japan, and South Korea did not expand subscribers to the same extent as those in the US, but they were able to expand their market share in the UK and Germany while failing to increase it in the other three countries. Local OTT players, especially those in Europe and Asia, might need to be more strategic in coping with US-based firms' expansion by materializing the positive interaction effects among the three strategies to increase both their subscriber base and market share. • This paper analyzes the effects of three strategies on OTT platform performance: Pricing, M&As, and Content investments. • Pricing and Content investments are key factors affecting market share and subscribership in global OTT markets. • OTT-specialized firms not in the US did not expand subscribers to the same extent as those in the US. [ABSTRACT FROM AUTHOR]

Double-sided laser beam welding of skin-stringer joints is a proven method for many industrial applications such as in aircraft assemblies where riveted differential joints are being replaced with welded integral structures. In the present study, dissimilar aluminum alloys of AA2024-0 and AA7075-T6 were laser welded on both sides in a T-joint configuration using a low-power Yb-fiber laser with the addition of a BA4047 filler wire. The optimized parameters were determined by developing a Mamdani fuzzy smart model. The influence of BA4047 filler wires on weld morphology was investigated using optical microscopy (OM) and scanning electron microscope (SEM). The cross-section of the joints revealed that the fusion zone (FZ) and heat affected zones (HAZ) are wider when filler wire was added as compared to those without it. This result shows that the low-power fiber laser has sufficient energy to melt the tip of the filler wire and subsequently the base materials, forming a liquid bridge to facilitate the smooth flow of molten metal between the stringer and the skin. No obvious voids were observed in the cross-sections of the joint interface. The strengths of joints were evaluated using a pull test, and hardness values were measured at the base metal (BM), FZ, and HAZ using the Vickers hardness test. At lower welding speeds with constant low-laser power, it was shown that the addition of the aluminum-silicon base alloy has increased the overall hardness and welding strengths of the samples. [ABSTRACT FROM AUTHOR]

We introduce an interactive user-driven method to reconstruct high-relief 3D geometry from a single photo. Particularly, we consider two novel but challenging reconstruction issues: i) common non-rigid objects whose shapes are organic rather than polyhedral/symmetric, and ii) double-sided structures, where front and back sides of some curvy object parts are revealed simultaneously on image. To address these issues, we develop a three-stage computational pipeline. First, we construct a 2.5D model from the input image by user-driven segmentation, automatic layering, and region completion, handling three common types of occlusion. Second, users can interactively mark-up slope and curvature cues on the image to guide our constrained optimization model to inflate and lift up the image layers. We provide real-time preview of the inflated geometry to allow interactive editing. Third, we stitch and optimize the inflated layers to produce a high-relief 3D model. Compared to previous work, we can generate high-relief geometry with large viewing angles, handle complex organic objects with multiple occluded regions and varying shape profiles, and reconstruct objects with double-sided structures. Lastly, we demonstrate the applicability of our method on a wide variety of input images with human, animals, flowers, etc. [ABSTRACT FROM AUTHOR]

Reducing production cost and upgrading current capacity are the key issues for the commercialization of YB2 Cu3O7-δ (YBCO) high-temperature superconducting coated conductors. In this paper, a novel double-sided ion-beam-assisted deposited (IBAD) MgO template has been proposed and introduced for the deposition of YBCO coated conductors on both sides, which contributes significantly to the performance improvement and production cost cutting. In this template, chemical solution derived amorphous Y2 O3 layer was coated on untreated hastelloy tapes to obtain nanometer-level flatted surface with root-mean-square roughness values of 0.8 and 0.5 nm (5 μm × 5 μm area) for each side, respectively. Based on the smooth surface, double-sided IBAD-MgO and homoepitaxial MgO films were deposited on the Y 2O3 coatings by a two-step process. The biaxial textures of meter-long double-sided MgO tape showed ω-scans of (200) MgO and Φ-scans of (220) MgO yield full width at half maximum values of 2.5°–3° and 4.5°–6°for one side, respectively, as well as 2.6°–3.2° and 5.6°–6.5°for the other side. Finally, the double-sided YBCO films deposited on the LaMnO3 buffered MgO template achieved a high-transition temperature of 90 K and an overall critical current of 290 A/cm at self-field (110 and 180 A/cm for each side). [ABSTRACT FROM PUBLISHER]

Double-sided Silicon Strip sensors (DSSD) can cover large areas and volumes of silicon with a relatively small amount of readout channels. If used for spectroscopy though, their resolution is limited by the large readout capacitance of p- and n-side strips. This paper presents the idea of small Silicon Drift Detector (SDD) cells whose anodes are connected to form n-side strips similar to double-sided strip sensors. Their combined n-side capacitance should be significantly lower than continuous strips and improve spectroscopic energy resolution. The p-side strips are used to deliver a prompt trigger signal and position information. Such concatenated sdds (c-SDD) can only be reasonably implemented for a strip pitch larger than the wafer thickness. [ABSTRACT FROM AUTHOR]

DSSIL was used in combination with inexpensive injection molded glassy polystyrene surfaces doped with an organic light emitting polymer to generate a series of planar light emitting diffractive optical elements. 2D diffractive structures with lateral and vertical features ranging from 1 to 0.5 μm and 30–125 nm were fabricated on glassy polystyrene surfaces using soft 1D PDMS gratings via multi step solvent imprint lithography (MSSIL). The scattering and transmission efficiencies of DSSIL PS surfaces and MSSIL PS surfaces were measured. Illumination (531 nm laser) of the DSSIL imprinted surface exhibited a 5% and a 4 fold increase in normal transmission and scattering efficiencies compared to PS surfaces imprinted on one side alone. The angular emission and distribution of patterned PS surfaces doped with a light emitting polymer were studied as well as the characteristics of the substrate and the effect of solvent polarity on luminescence quenching. The results show that MSSIL and DSSIL are facile, inexpensive techniques highly suitable for the routine fabrication of novel symmetric and asymmetric diffractive structures in an interdisciplinary laboratory. [ABSTRACT FROM AUTHOR]

We have successfully employed a double-sided process to deposit MgO buffer layers on both sides of amorphous Y 2 O 3 surface for double-sided YBa 2 Cu 3 O 7 − δ (YBCO) coated conductors (CCs) for the first time, the structure of which is of great prospect to improve the performance and cut the production cost. The biaxial textures of MgO buffer layer are noticeably affected by the ion energy and film thickness, which is demonstrated by X-ray diffraction. The best biaxial texture of double-sided MgO films shows ω -scan of (002) MgO and Φ -scan of (220) MgO yield full width at half maximum values of 4° and 7.8° for one side, respectively, as well as 3.5° and 6.7° for the other side. The subsequent double-sided YBCO films are deposited on the as-prepared MgO template with entire critical current of over 300 A/cm for both sides. [ABSTRACT FROM AUTHOR]

In this paper, the design and development of a double-sided air-cored tubular generator (DSTG) is presented. The characteristics of air-cored slot-less structures are investigated in terms of power density and efficiency. This is highly desirable for small- and medium-sized renewable energy conversion systems. In this paper, an analytical tool based on the magnetic vector potential method is built in order to achieve a fast but accurate method by which the machine is analyzed. The analytical model is validated by finite-element (FE) analysis. Further design improvements based on the analytical and FE models are then suggested in order to enhance the performance of the DSTG. The final design of the DSTG is validated by the test results from a developed prototype of the DSTG. [ABSTRACT FROM AUTHOR]

We have successfully employed metal-organic chemical vapor deposition (MOCVD) technique to simultaneously deposit double-sided YBaCuO (YBCO) films on both sides of YO/yttria-stabilized zirconia (YSZ)/CeO (YYC) buffered biaxially textured Ni-5 at.% W substrates, which is of great prospect to cut the production cost of YBCO coated conductors. X-ray diffraction analysis revealed that both sides of YBCO film were purely c-axis oriented and highly textured. The ω-scan of (005) YBCO and ϕ-scan of (103) YBCO yielded full width at half maximum (FWHM) values of 4.9° and 6.6° for one side of double-sided YBCO film, respectively, as well as 4.4° and 6.4° for the other side. The current transportation measurements performed on such double-sided 500 nm-thickness YBCO films showed the self-field critical current density ( J) at 77 K of 0.6 MA/cm and 1.2 MA/cm, respectively. Further research is in the process of exploring new solution to improve the J in practice. [ABSTRACT FROM AUTHOR]

A double-sided light source based on field emission (FE) using an alternating current (ac) power source is demonstrated. Electrode plates acted as cathode or anode consisting an indium tin oxide glass, a screen-printed ZnS phosphor layer and urchin-like \alpha\-Fe2O3 emitters coated on the layer. Two pieces of the plates were assembled together with the coated surfaces facing each other to make a parallel-plate, diode-structure FE device with a gap distance of 300 \mum. The 1-cm^2 device shows a double-sided luminance distribution with a turn-on field of 2.2 V/\mum, 90.23% uniformity and a maximum luminance of 8750 cd/m^2 at 2 kV. The novel structure and ac model operation provide a double-sided luminance, high brightness, antiarcing, good thermal management, and long lifetime. [ABSTRACT FROM PUBLISHER]

Dynamic full-thickness skin wound healing remains an intricate problem due to the humid environment and frequent exercise. Recently, multifunctional hydrogels have a great promise in wound repair. However, traditional hydrogels only keep the wound moist, protect the wound from bacterial infection, and cannot actively drive dynamic wound closure. Inspired by embryo wound active closure, we constructed a double-sided thermoresponsive mechanoactive (DTM) hydrogel that combines good flexibility, self-healing, wet-tissue adhesion, and antibacterial functions. The strong adhesion of the hydrogel to biological tissues is attributed to "multiple hydrogen bonding clusters" without any chemical reaction. The contraction force triggered by temperature is quickly transmitted to dynamic wound edges to resist external mechanical forces and drive wound closure, which can effectively avoid damage to surrounding healthy tissue and reduce the risk of scarring, infection, and inflammation caused by sutures, staples, or clips. Strikingly, in vivo, this hydrogel bandage actively enhanced wound repair in a full-thickness skin defect model by promoting collagen deposition, facilitating angiogenesis, and accelerating wound re-epithelialization. This mechanoactive biological method will provide a facile strategy for joint wound management and demonstrates strong potential in tissue remodeling.

Highlights: [•] Mid-frequency AC sputtering provides significant advantages. [•] Double-sided Y2O3 seed layers are prepared with high speed of 35m/h. [•] Sputtering voltage control was used to deposited epitaxial high quality films. [•] Coherent textures and surfaces of both sides of CeO2/YSZ/Y2O3 are achieved. [ABSTRACT FROM AUTHOR]

Highlights: [•] Copper deposition mechanism is stated and mathematical models of the Cu electroplating are established by a series of electrochemical equations. [•] Finite element models (FEM) are built to simulate two different kinds of copper electroplating processes in through-hole via. [•] Experiments show the feasibility of the Cu TSV fabrication under different conditions based on the simulation optimized results. [•] Defect-free Cu TSVs are successfully applied to the Wafer Level Packaging (WLP) Pirani vacuum gauges for the vacuum packaging of MEMS. The devices are proved to be robust and high accuracy. [ABSTRACT FROM AUTHOR]

This study proposes a double-sided linear flux-switching permanent magnet machine for direct drives in precision servo applications. The method of asymmetry distribution of stator teeth (ADST) is introduced to reduce the cogging force. Moreover, cogging force, back-EMFs, and thrust force are calculated by using finite element analysis. In addition, the performance comparison is carried out to verify the accuracy and effectiveness of the method of cogging force reduction. Finally, the experiment confirms the reasonability and feasibility of the ADST method. [ABSTRACT FROM PUBLISHER]

Abstract: Design and fabrication of optical films to increase visual brightness of OLED (Organic Light-Emitting Diode) lighting units are presented in this paper. This study explores a new fabrication process combining precision machining, photolithography, and micro forming techniques to make a double-sided optical film. One side of the optical film is made of micro triangular-pyramidal array (MTPA), and the other side is micro gapless hexagonal microlens array (GHMA). First, Taguchi Method is applied to determine the optimal microstructure configuration by the assistance of the commercial optical software, FRED. Second, tungsten (W) mold of MTPA as the first mold is manufactured by precision machining including optical projection grinding, lapping, and polishing processes. Nickel–cobalt (NiCo) mold of GHMA as the first mold of the other side is fabricated by using LIGA (Lithographie Galvanoformung Abformung)-like process. To obtain inverse molds, poly dimethylsiloxane (PDMS) is used to replicate W and Ni–Co molds, which are served as the secondary molds for two sides, respectively. With these molds, UV (ultraviolet) curable resin was used to make double-sided optical film. Then the optical film was packaged on OLED unit to measure its optical properties by PR 650 equipment. The result shows that both brightness and uniformity can be improved by using this film. [Copyright &y& Elsevier]

Abstract: Y2O3 films were deposited on both sides of biaxially textured Ni–5at.%W substrates by reel-to-reel DC. magnetron reactive sputtering, serving as a seed layer for high performance coated conductors. The deposition parameters, such as water vapor pressure, substrate temperature and sputtering power, were systematically studied. The YSZ layer and CeO2 layer were fabricated on Y2O3 buffered Ni–W tapes using the same deposition system. X-ray diffraction analysis confirmed that optimized double-sided CeO2/YSZ/Y2O3 buffer layers showed a significant improvement in in-plane and out-of-plane texture. Atomic force microscope revealed a smooth, dense and crack-free surface morphology. YBa2Cu3O7- δ films grown on double-sided CeO2/YSZ/Y2O3 buffered Ni–W tapes by D.C. sputtering exhibited a critical current density of 1.26MA/cm2 at 77K for each side. [Copyright &y& Elsevier]

We present a 6th order pseudo high-pass filter implemented by a modified version of the double-sided parallel-strip line, in which the width of the dielectric substrate is identical to the width of the conducting strips. The filter, the associated compact circular balun, and the SMA connectors are designed and simulated by means of the CST Microwave Studio, and implemented on a Rogers 4003C substrate. The experimental results are in good agreement with the simulations, and good scattering properties are achieved. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2691–2694, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24741 [ABSTRACT FROM AUTHOR]

Nb-doped Pb(Zr20,Ti80)O3 (PZT) films were grown on both sides (side I and II) of Pt/TiOx/SiO2/Si(100)/SiO2/TiOx/Pt wafers by chemical solution deposition. The structures of these films were characterized by X-ray diffraction and scanning electron microscopy. The effective transverse piezoelectric coefficients of the poled films were in the range of 2.5∼ 6.4 C/m2. {100}-textured films show the highest value of e31,f. A cantilever was actuated from side I (or II) and sensed from side II (or I). A linear relationship between charge and driving voltage was observed at a quasi-static frequency of 10 Hz. The resonant frequency of the cantilever was found to be 260 Hz. These results clearly indicate that double-sided PZT films are suitable for actuation and sensing of a device. [ABSTRACT FROM AUTHOR]

A new double-sided electromagnetic wave absorber allowing transmission is proposed. In the conventional permeable wave absorber, a resistive film is attached to a lossless dielectric layer. However, this is not nonreflective for an incident wave on the resistive film side. In the present paper, a basic structure is considered in which there is no reflection on both sides of the absorber. A simple structure made of two resistive films inserted between three dielectric layers is proposed. The nonreflection condition of the present wave absorber is derived by means of the equivalent circuit, and the reflection and transmission characteristics are derived for given permittivities of the dielectric layers. It is found that the bandwidth of the reflection coefficient does not significantly depend on the permittivity of the inner layer and that the permittivity of the outer layers is increased and that of the inner layer is decreased in order to make the transmission coefficient smaller. The wave absorber is fabricated and measured for confirmation of the validity of the theory. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 90(6): 1–8, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20369 [ABSTRACT FROM AUTHOR]

Abstract: The two outermost layers of the ALICE Inner Tracking System consist of 1698 double-sided silicon microstrip modules, which form the Silicon Strip Detector (SSD). The SSD modules offer several novelties, which include the use of TAB-bonding technique for the connection of the front-end electronic via thin aluminium-polyimide cables. The module as well as its parts will be described and the assembling procedure illustrated. [Copyright &y& Elsevier]