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ABSTRACT Objective Materials and Methods Results Conclusions Clinical Significance The aim of the present study was to investigate the relation of the implant position to the implant crown and analyze the location and magnitude of bite force.The dimensions of 49 posterior implant‐supported restorations were recorded in terms of: 1. implant diameter, 2. crown length, 3. crown width, 4. crown height, 5. occlusal surface of the restoration. The crown/implant height was measured and the distance between the implant center and the restoration center revealed the size of intra‐coronal cantilevers. The occlusal force analysis determined the point and magnitude of loading. Correlation coefficient r was used for the statistical process and statistical control was carried out with the aid of t‐test with minimum level of significance p < 0.05. ‐ The mean crown‐to‐implant ratio was 0.9 and in short implants (< 10mm) the ratio was 1.28. ‐ Intra‐coronal cantilever extensions ranged from 2.1 mm to 6.35 mm depending on crown size. ‐ Occlusal loading was identified in cantilever areas of the crown. The mean crown‐to‐implant ratio was 0.9 and in short implants (< 10mm) the ratio was 1.28.Intra‐coronal cantilever extensions ranged from 2.1 mm to 6.35 mm depending on crown size.Occlusal loading was identified in cantilever areas of the crown. ‐ Implant center deviates from crown center in 71%–82% of the cases depending on site location. ‐ Implants with non‐ideal position may support a functionally occluding crown. Implant center deviates from crown center in 71%–82% of the cases depending on site location.Implants with non‐ideal position may support a functionally occluding crown.Intra‐coronal cantilevers are a critical factor to avoid clinical complications and should be taken under consideration both in the planning and fabrication phase of implant restorations. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerator (TENG), as a new technique for energy capture, has unique advantages in harvesting high‐entropy energy. In view of the wind‐induced vibration characteristics of power transmission lines, the symmetric elastic bistable triboelectric nanogenerator (EB‐TENG) is introduced in this work. The core component of the EB‐TENG is the elastic bistable cantilever beam structure, which is designed by introducing an elastic perturbation structure to the conventional cantilever beam. This beam results in several sub‐resonance frequencies in addition to the natural frequencies, which broadens the frequency band of the EB‐TENG. In addition, the EB‐TENG adopts a symmetrical cantilever beam to ensure effective harvesting of vibration energy, even in situations of self‐tilting and external tilting vibration. The experimental outcomes confirm that the EB‐TENG can significantly harvest vibration energy in the 7–60 Hz frequency range and delivers the maximum peak power of 2.846 mW, which meets the major vibration frequency range of power transmission lines under the action of breeze. Finally, self‐powered strategy based on EB‐TENG online monitoring devices (such as tower obstruction lights, temperature and humidity sensors, and line high temperature wireless alarms) is constructed. This work helps promote the application of in‐situ self‐powered monitoring based on TENG in smart transmission lines. [ABSTRACT FROM AUTHOR]

Quantum sensors find applications ranging from material science to biophysics. Nitrogen‐vacancy (NV) center in diamond has been successfully implemented for measuring various types of signals. Optical NV center readout, routinely used in confocal microscopes, allows achieving high spatial resolution down to the diffraction limit. This work describes in detail the combined confocal‐atomic‐force microscope (confocal‐AFM), which takes advantage of sharp AFM cantilevers, and shows its possible applications for nanoscale resolution. It demonstrates the sub‐diffractional localization of NV centers with platinum‐coated cantilevers and the ability to separately address optically unresolved sensors using cantilevers with ferromagnetic coating. The presented setup exhibits a lateral resolution of 13 nm, providing a tool for nanoscale quantum sensing. [ABSTRACT FROM AUTHOR]

Once constructed, the Baku White City pedestrian bridge will be a landmark for the newly developed White City district in the east of the Capital. Designed by UNStudio, the bridge crosses the highway of 8th November Avenue and connects the newly build city to the seaside, forming a wide promenade. Due to the pending construction of the mall as future bridge support, the bridge had to be redesigned. A cantilevering viewing platform will highlight the bridge's ending. This paper covers the structural design of the architecturally shaped cable stayed bridge, supported through a 46 m high A‐shaped, slightly curved pylon. Based on 3‐D modelling in Rhino® and Grasshopper®, the FE‐software SOFISTIK® is used both for cable force finding and bridge design. The structural system, steel structure's specific detail for cable connection and its design approach have been documented. [ABSTRACT FROM AUTHOR]

Highlights To efficiently design the stiffness of the laminated composite blade‐like structure, an analytical method to assess deformation of variable cross‐section laminated beam under cantilever bending load was developed, in which a local ply density matrix method was introduced to characterize the ply‐up in arbitrary cross‐section after ply drop‐off process and infinitesimal element segment method was used to convert complex variable cross‐section specimen into local equal cross‐section beam structure. The model was validated by the cantilever beam experiment with relative predicted error of stiffness of 5.7%. Inner and outer ply drop‐off models were analyzed using the proposed analytical method. The results show that: (1) stiffness of the outer ply drop‐off model is the highest, at 13.07 N/mm, while that of the inner ply drop‐off model 2 is the lowest, about 17.8% lower than the outer ply drop‐off model; (2) maximum relative deformation difference between the inner ply drop‐off model 2 and outer ply drop‐off model is 21.7% at the free side of the cantilever beam. It indicates that anti‐deformation ability of the variable cross‐section laminated structure can be efficiently designed by the proposed analytical method, especially for the section close to the free side. Developed a bending stiffness prediction method for composite beam. Variable cross‐section feature of the composite laminate was considered. Local ply density matrix method was introduced to characterize ply drop‐off. Proposed method was validated by cantilever beam bending experiment. Inner and outer ply drop‐off models were compared by the proposed method. [ABSTRACT FROM AUTHOR]

Piezoelectric cantilever beams are broadly implemented in energy harvesting. However, simple cantilever‐shaped harvesters are mostly unimodal. Herein, a T‐shaped cantilever beam harvester that can have a bimodal amplitude–frequency curve is developed. The modal of the system is designed in COMSOL finite‐element software and the dynamic behavior is carried out using the finite element simulation. Then, validation experiments are used to estimate the results of finite‐element analysis and it is concluded that the simulation results are in good agreement with the experimental data. Furthermore, the frequency response curves are plotted for various system parameters so as to discuss the influence of these parameters on the bandwidth of the harvester. It is found that there is an optimal resistance that can obtain the P = 2.87 mW maximum power. Finally, theoretical modeling is established and exact analytical solutions are derived, and the comparisons of theoretical, numerical, and experimental results are implemented. It is found that the results of these three methods are consistent. In addition, all of these predictions show that the bidirectional coupling induces the bandwidth increases. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the vertical misfit, stress distribution around dental implants, and cantilever fracture strength of 3‐unit implant‐supported cantilever fixed partial dentures (FPDs) using frameworks made from different materials and manufacturing techniques. Materials and Methods: Forty FPDs were fabricated and divided into 5 groups (n = 8) based on the framework material used: LAS Co‐Cr (Conventional casting—laser welding); TIG Co‐Cr (Conventional casting –TIG welding); OP Co‐Cr (Conventional casting—one‐piece); CAD Co‐Cr (CAD‐CAM); and CAD Zr (CAD‐CAM ZrO2). The vertical misfit was evaluated before porcelain application (T1) and before (T2), and after thermomechanical cycling (T3) by stereomicroscopy. Cantilever fracture strength was tested with a 50 kN (5000 kgf) load cell at a crosshead speed of 0.5 mm/min. Qualitative and quantitative photoelastic analysis was performed to evaluate stress distribution at seven specific points in five FPDs (n = 1/group) subjected to occlusal loading. Results: Only the molar showed interaction among the three factors (G × S × T; F(20.932) = 1.630; p = 0.044). Thermomechanical cycling (T2 vs. T3) had a significant effect on intra‐group vertical misfit in molar, especially in LAS Co‐Cr (Δ = 5.87; p = 0.018) and OP Co‐Cr (Δ = 5.39; p = 0.007), with no significant effect in premolar (p > 0.05). Ceramic application combined with thermomechanical cycling (T1 vs. T3) caused a significant intra‐group increase in vertical misfit in all groups, both in the molar and premolar (p < 0.05). OP Co‐Cr was associated with greater vertical misfit and stress concentration. Frameworks manufactured by the CAD‐CAM system exhibited lower vertical misfit and better stress distribution. FPDs with metal frameworks (>410.83 ± 72.26 N) showed significantly higher fracture strength (p < 0.05) than zirconia (277.47 ± 39.10 N), and the first signs of ceramic veneering fracture were observed around 900 N. Conclusions: FPDs with frameworks manufactured using a CAD‐CAM system appear to be associated with lower vertical misfit and better stress distribution, although the section of the frameworks followed by welding may be a viable alternative. In addition, metal frameworks exhibit high fracture strength. [ABSTRACT FROM AUTHOR]

We propose a novel high‐performance dual‐resonance enhanced photoacoustic spectroscopy (DRE‐PAS) gas sensor based on a highly sensitive fiber optic cantilever beam microphone and a high‐Q spherical photoacoustic cell (PAC). The first‐order resonant frequency (FORF) of the spherical PAC is analyzed by finite element analysis to match the FORF of the cantilever microphone for the double resonance enhancement of the photoacoustic signal. The photoacoustic spectroscopy (PAS) system, including the DRE‐PAS sensor, a 1532.8 nm distributed feedback laser, and a high‐speed spectrometer, has been successfully exploited for trace acetylene (C2H2) detection. The experimental results show that the limit of detection (LOD) is 106.8 parts‐per‐billion (ppb) with an integral time of 1 s, and the LOD can be further reduced to 11.03 ppb by Allan‐Werle deviation for 100 s integral time. The normalized noise equivalent absorption coefficient can be obtained as 2.44 × 10−8 cm−1 WHz−1/2. The reported DRE‐PAS gas sensor has the superior characteristics of photoacoustic signal enhancement, high sensitivity, and strong antielectromagnetic interference capability, which can provide a new solution for PAS development. [ABSTRACT FROM AUTHOR]

This paper describes an improved process for controlling the initial deflection structure of cantilever‐type MEMS tactile sensors. By using residual stress, deposition sequence, and metal layer patterns, the initial deflection of the cantilever was successfully aligned to the same initial deflection with micron accuracy and 97% yield in a simpler and easier process than previous processes. This enables a reduction in the number of processes and flexible control of deflection, which is expected to improve yield and shorten fabrication time. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Summary: Tensegrity systems are construction system that offers solutions for lighter designs compared with a standard truss system consisting of tension and compression elements. Due to their structure, they are recommended in the design of space structures due to the use of lighter and easy‐to‐assemble structural elements such as cables, ropes, and similar to provide the desired durability. In this study, energy minimization was carried out to solve the structural element displacements. It is expected to reduce the total potential energy of the system with minimization. By minimizing the total potential energy of the tensegrity system models, the displacement of each building element is found for the equilibrium condition. Tensegrity models were analyzed by minimizing energy via the adaptive harmony search (AHS) algorithm. In this research, two distinct tensegrity structure specimens were employed. One comprised a cantilever beam, while the other adopted a cyclic model, forming eight equal octagons from eight nodes at both the base and the top. Additionally, an examination was conducted on a two‐layer iteration of the cyclic model. The method is robust for both space and planar tensegrity structures, allowing the determination of deformed shapes under various loads without design assumptions. The TPO/MA method demonstrates superiority in handling nonlinear and barely stable systems, as evidenced by examples illustrating its efficacy in maintaining structural form under increasing loads and challenging conditions. [ABSTRACT FROM AUTHOR]

Objectives: To simulate the replacement of a premolar with an implant‐supported cantilever fixed dental prosthesis (ICFDP) and how the fracture load is affected by implant type, positioning within the zirconia blank, and aging protocol. Materials and Methods: Seventy‐two ICFDPs were designed either within the enamel‐ or dentin layer of a 4Y‐PSZ blank for bone‐level and tissue‐level titanium‐zirconium implants. Fracture load was obtained on the cantilever at baseline (no aging) or after aging in a chewing simulator with the load applied within the implant axis (axial aging) or on the cantilever (12 groups with n = 6). A three‐way ANOVA was applied (α =.05). Results: A three‐way ANOVA revealed a significant effect on fracture load values of implant type (p =.006) and aging (p <.001) but not for the position within the zirconia blank (p =.847). Fracture load values significantly increased from baseline bone level (608 ± 118 N) and tissue level (880 ± 293 N) when the implants were aged axially, with higher values for tissue level (1065 ± 182 N) than bone level (797 ± 113 N) (p <.001). However, when the force was applied to the cantilever, fracture load values decreased significantly for tissue‐level (493 ± 70 N), while values for bone‐level implants remained stable (690 ± 135 N). Conclusions: For ICFDPs, the use of bone‐level implants is reasonable as catastrophic failures are likely to be restricted to the restoration, whereas with tissue‐level implants, the transmucosal portion of the implant is susceptible to deformation, making repair more difficult. [ABSTRACT FROM AUTHOR]

This paper presents the findings of a large‐scale experimental study that focus on assessing structural behavior of reinforced concrete (RC) cantilever slabs with carbon/epoxy fiber‐reinforced polymer (CFRP) composite strips using a near‐surface‐mounted (NSM) approach. The NSM/CFRP system evaluated in this study was implemented in strengthening the shoulders of the Slide Canyon Bridge in California, USA. The experimental phase is divided into two main parts: (i) determining the design parameters for NSM, including the bondline strength through pull‐out tests, and (ii) conducting a practical evaluation of the bending behavior of original and retrofitted RC cantilever slabs, each with varying NSM reinforcement and three different development lengths. Results of this study indicated that the use of NSM‐CFRP has a considerable benefit in that it significantly improves ductility and changes the failure mode of the unstrengthened RC slab from the typical brittle shear‐based failure mode to a more ductile flexural‐based failure mode. The large‐scale slab specimens' performances, which had different development lengths, showed little variance, except for the slab specimen with a development length of 457.0 mm that exhibited an appreciable flexural stiffness as compared to other specimens evaluated in this study. In order to simulate the serviceability and ultimate behavior of the RC slab specimens, linear and nonlinear finite element analyses were performed. A satisfactory agreement between numerical and experimental results was achieved especially at load level prior the initiation of large‐size cracks. [ABSTRACT FROM AUTHOR]

Recently, electret‐based triboelectric nanogenerator (E‐TENG) showssignificant advantages for energy harvesting applications, including a largeelectric current and high output stability. Inthis investigation, porous biocompatible polylactide (PLA) film is prepared for E‐TENG applications. They found that thesurface potential of the porous PLA‐based bioelectret film is maintained at2.1 kV after 86 days of decay,. The measurement data from theE‐TENG‐based cantilever beam showed that the E‐TENG reached an open‐circuitvoltage (Voc) of 184 V and a short circuit current (Isc)of 22.4 µAat 13.8 Hz. Furthermore, the E‐TENG and the PVDF‐based piezoelectric nanogenerator (PENG) are combined to create a hybridNG for energy harvesting applications. The data indicate that the maximumoutput power of the hybrid NG reached 73.5 µWat 6 MΩ,which is 30.7% and 1.91‐fold higher than that of the PENG and the E‐TENG,respectively. The hybrid NG is used as a powersource to drive a wireless temperaturetransmission system, which can receive a temperature transmission signal from 20 m away. The advantages of biocompatibility,softness and ease of processing make the porous PLA film a great candidate forwearable devices applications. [ABSTRACT FROM AUTHOR]

The kinetics and durability of conversion‐based anodes greatly depend on the intrinsic stress regulating ability of the electrode materials, which has been significantly neglected. Herein, a stress dissipation strategy driven by multi‐interface built‐in electric fields (BEFs) and architected structure, is innovatively proposed to design ultrafast and long‐term sodium ion storage anodes. Binary Mo/Fe sulfide heterostructured nanorods with multi‐interface BEFs and staggered cantilever configuration are fabricated to prove our concept. Multi‐physics simulations and experimental results confirm that the inner stress in multiple directions can be dissipated by the multi‐interface BEFs at the micro‐scale, and by the staggered cantilever structure at the macro‐scale, respectively. As a result, our designed heterostructured nanorods anode exhibits superb rate capability (332.8 mAh g−1 at 10.0 A g−1) and durable cyclic stability over 900 cycles at 5.0 A g−1, outperforming other metal chalcogenides. This proposed stress dissipation strategy offers a new insight for developing stable structures for conversion‐based anodes. [ABSTRACT FROM AUTHOR]

Buckling of a simple supported and cantilever nano‐rod and under action of self‐weight was modeled, taking into account the surface effect according to two models of surface elasticity – Gurtin–Murdoch and Steigmann–Ogden. The size effect under the buckling was studied by the Ritz method using two kinematic hypotheses, known as the rod theories of Euler–Bernoulli and Timoshenko. The simulation results were compared depending on the accepted surface elasticity model and the kinematic hypothesis. [ABSTRACT FROM AUTHOR]

We deposited micro‐scale organic light‐emitting diodes(OLEDs) with a red‐emitting material on an ultrathin organic film and demonstrated a flexible device with a cantilever form factor. This platform satisfied the necessary light irradiation conditions applicable for phototherapeutic applications and also holds potential for biomedical implantable areas such as neurotherapy. [ABSTRACT FROM AUTHOR]

Elasticity is a critical measure of the eating quality of Udon noodles. To characterize the elasticity of Udon noodles, an instrumental method based on the cantilever beam bending test was established. Firstly, the optimum test parameters were determined. Then, texture profile analysis, compression, tension, and cantilever beam bending methods were used to measure the elasticity of 25 commercial Udon noodles with different shapes and sizes, and the correlations between elasticity obtained by the above instrumental methods and sensory evaluation were analyzed. Finally, how the shape and size of Udon noodles influenced their elasticity was discussed in detail. Within the deflection of 2.0 mm, the force increased approximately linearly with increasing deflection, and moderate loading speed (0.5–1.0 mm/s) should be used in the cantilever beam bending experiments to improve the accuracy of results. The bending stiffness obtained by the cantilever beam bending method exhibited a higher coefficient of variation and stronger correlation with the elasticity of sensory evaluation than other instrumental methods. Furthermore, the Udon noodle sample with a higher size, especially the thickness, had higher elasticity, and the Udon noodle sample with a rectangular cross‐section showed higher elasticity than that with a circular cross‐section. In conclusion, the bending stiffness determined by the cantilever beam bending method could be used to characterize the elasticity of cooked Udon noodles. [ABSTRACT FROM AUTHOR]

Microcantilevers are at the heart of atomic force microscopy (AFM) and play a significant role in AFM‐based techniques. Recent advancements in multifrequency AFM require the simultaneous excitation and detection of multiple eigenfrequencies of microcantilevers to assess more data channels to quantify the material properties. However, to achieve higher spatiotemporal resolution there is a need to optimize the structure of microcantilevers. In this study, the architecture of the cantilever with gold nanoparticles using a dip‐coating method is modified, aiming to tune the higher eigenmodes of the microcantilever as integer multiples of its fundamental frequency. Through the theoretical methodology and simulative model, that integer harmonics improve the coupling in multifrequency AFM measurements is demonstrated, leading to enhanced image quality and resolution. Furthermore, via the combined theoretical‐experimental approach, the interplay between induced mass and stiffness change of the modified cantilever depending on the attached particle location, size, mass, and geometry is found. To validate the results of this predictive model, tapping‐mode AFM is utilized and bimodal Amplitude Modulation AFM techniques to examine and quantify the impact of tuning higher‐order eigenmodes on the imaging quality of a polystyrene‐polymethylmethacrylate (PS‐PMMA) block co‐polymer assembly deposited on a glass slide and Highly Ordered Pyrolytic Graphite (HOPG). [ABSTRACT FROM AUTHOR]

A novel, cost‐effective strategy for sensing performance enhancement of cantilever‐shaped, mass‐sensitive sensors is presented. The developed strategy relies on the introduction of macroporosity in the recognition unit. The developed sensors are successfully applied in air humidity monitoring as well as in chemical sensing. As mass‐sensitive transducers, polymer microelectromechanical systems (MEMS) in the form of poly(vinylidene fluoride‐trifluoroethylene) [P(VDF‐TrFE)] cantilever resonators are specifically developed. These resonators are modified with a hierarchically structured macroporous poly(2,3′‐bithiophene) film, acting as a sensing layer. The design of the recognition layer takes advantage of the synergistic combination of inverse opal structuring, surface imprinting, and semi‐covalent imprinting of proteins. The resulting cantilever resonators are first successfully tested for air humidity monitoring in the whole relative humidity range (ca.10 – 90%). When the recognition layer is composed of human serum albumin‐imprinted polymer (HSA‐MIP) with a hierarchical structure, it can also be used as a selective chemosensor in a concentration range from 10 pM to 20 µM. The obtained results demonstrate that the macroporosity of the receptor film significantly enhances the sensor performance. [ABSTRACT FROM AUTHOR]

For modeling materials with size‐effects, the classical Cauchy linear elasticity theory and first‐order homogenization procedures are insufficient. Enriched continua are able to capture such phenomena in principle. In this work, we model the size‐effects of metamaterial beams via the relaxed micromorphic continuum. The material parameters of the relaxed micromorphic model are evaluated. We present a simple procedure for the determination of the material parameters based on the fact that the model operates between two well‐defined scales that are the classical continuum scales of macroscopic linear elasticity, whose stiffness is given by a known macroscopic elasticity tensor, and a microscopic scale with a microscopic elasticity tensor yet to be identified. The size‐effects of metamaterial cantilevers under traction load are captured successfully. [ABSTRACT FROM AUTHOR]

Key Clinical Message: The cantilevered fixed partial denture (CFPD) is gaining recognition as a sound method of replacing missing teeth in the posterior sector. The purpose of this case report is to demonstrate that this type of restoration can be performed in a single appointment. A 39‐year‐old patient presented herself to the dental department; she showed agenesis of the two first maxillary premolars with a totally closed mesio‐distal gap and a recent loss of the 2 s maxillary premolars. This case report concerns the replacement of the upper left second premolar. The patient was treated with a mesial CFPD resting on an "onlay‐like" retainer on the first molar and replacing the missing premolar with a cantilevered pontic. The dimensions of the connection's cross‐section were maximized as much as possible (>20 mm2). The restoration was designed and produced using chairside CAD‐CAM from a milled‐reinforced glass–ceramic block (Emax CAD, Ivoclar Vivadent). The aesthetic and functional integration of the prosthesis was successful. The patient was examined at 11 months for a follow‐up. At this early stage, satisfactory dental hygiene was observed, associated with a smooth prosthetic fit, no periodontal inflammation, normal probing, and no abnormal dental mobility. [ABSTRACT FROM AUTHOR]

A modified element‐free Galerkin (EFG) method that combines the Heaviside enrichment and diffraction method is used to study crack propagation problems by employing a cohesive zone model (CZM) with an exponential traction separation law (TSL). The generalized displacement control method (GDCM) is adopted to solve the nonlinearity arising during the damage evolution. The proposed methodology is applied to (1) uncracked three‐point bending (TPB) and (2) adhesively bonded: (a) cracked double cantilever beam (DCB), and (b) end‐notched flexure (ENF) problems. In the passing, a simple 1D study is considered to demonstrate the advantage of level‐set enrichment coupled with CZM. Several parametric studies have been carried out on the EFG method and GDCM (reference and incremental load parameter). The results obtained by the proposed methodology agree well with the experimental/reference results. Specific advantages of GDCM on computational time, number of iterations, and ability to capture snapback vis‐à‐vis the popular Newton–Raphson technique are presented. Highlights: Generalized displacement control method (GDCM) is used to handle material nonlinearityModified EFG method is used for mode I and mode II interface fracture studiesThe GDCM is twice faster than the Newton–Raphson technique for interface fractureDifferent intensities of snapback behavior is captured efficiently by the GDCM [ABSTRACT FROM AUTHOR]

This paper presents a test case to help validate simulation codes for contact problems involving beams. A closed form solution is derived and the comparison is made with a finite element (FE) implementation that uses the mortar method for enforcing the contact constraints. The test case consists of a semi‐infinite cantilever beam subjected to a constant distributed load and experiencing frictionless contact with a straight rigid substrate. Both an Euler‐Bernoulli and a Timoshenko beam model are considered and the influence of the differing kinematic hypotheses is analyzed. In the case of the Euler‐Bernoulli beam the distributed contact force is equal to the load along the contact region except at the boundary where a point load appears. On the contrary, the rigid substrate exerts a fully distributed load on the Timoshenko beam which decays exponentially from the first contact point and tends towards the applied load. The rate of decay depends on the relative shear deformability. Moreover, whereas in the first case the transverse shear force is discontinuous, it becomes continuous when allowing for shear deformation. An example of benchmarking is given for a particular FE code. The error with respect to the exact solution can be computed and it is shown that the numerical solution converges to the analytic solution when the FE mesh is refined. [ABSTRACT FROM AUTHOR]

Piezoelectric energy harvesters based on Pb(Zr0.5Ti0.5)O3 (PZT) ceramics have been extensively studied for various low‐power applications. Herein, unprecedented multiple‐harvester structures with record‐breaking performance are proposed for targeting nonresonant‐frequency or extremely low‐frequency applications. Exceptional combinations of PZT with three different relaxor materials, namely, Pb(Co1/3Nb2/3)O3 (PCN), Pb(Ni1/3Nb2/3)O3 (PNN), and Pb(Zn1/3Nb2/3)O3 (PZN), are systematically investigated in terms of their structural changes and piezoelectricity. Following the optimization of the PCN–PZT, PNN–PZT, and PZN–PZT systems in terms of piezoelectricity and power generation, a few device structures are designed using the advantages of each system. For example, the highest g31 composition of 0.2PCN–0.8PZT is combined with the highest d31 of 0.4PZN–0.6PZT to maximize the power generation in the two‐parallel‐tape structure. Multilayer harvester structures with up to four layers are also evaluated to correlate the enhanced voltage and current with the layer thickness and effective area for surface‐charge polarization. The four‐layer 0.4PZN‐0.6PZT unimorph cantilever demonstrates exceptional energy‐harvesting performance of ≈535.9 µW, corresponding to the record power density of ≈10 mW cm−2 g−2 Hz−1 at 2 Hz. The outstanding outcome is believed to be a benchmark for various nonresonant‐frequency applications. [ABSTRACT FROM AUTHOR]

Objectives: To test the reliability of full zirconia implant‐supported fixed dental prostheses with cantilever extension (FDPCs) after at least 1 year of function. Materials and Methods: Thirty‐five patients in need of implant‐supported single unit crowns (SUC) and FDPCs in posterior areas were enrolled. After implant placement, patients were rehabilitated with screw‐retained full‐zirconia FDPCs. Implant survival rate, pocket probing depth (PPD), presence/absence of bleeding on probing (BoP), and presence/absence of mechanical/technical complications were recorded. Mesial and distal radiographic marginal bone levels (mBLs) from baseline (i.e., recall appointment 3–6 months after implant loading [T0]) to the follow‐up examination (i.e., latest recall appointment after at least 12 months after T0 [T1]), were calculated. Results: Thirty patients with 34 FDPCs (31 SUCs and 3 FDPs) supported by 37 implants were available for analysis after a mean loading time of 2.6 ± 1.5 years (range: 13–87 months). No implants were lost. MBLs and mean PPD values did not change statistically significantly from T0 to T1 from 0.92 mm ± 0.42 to 0.96 mm ± 0.38 (95% CI: −0.07/0.17; p =.418) and from 2.99 mm ± 0.70 to 3.27 mm ± 0.71 (95% CI: −0.11/0.68; p =.25) respectively. Peri‐implant mucositis was diagnosed in 22 cases. Screw‐loosening and zirconia chipping occurred 1× in 4 patients. Conclusion: Within the limitations of the present proof‐of‐principle study, the use of full‐zirconia FDPCs in posterior areas seems a valid and safe short‐term treatment option. [ABSTRACT FROM AUTHOR]

In this paper, the authors investigate energy harvesting on railway bridges. A tuning process based on a statistical analysis of the mechanical energy generated by a lumped‐mass model is presented and validated. A cantilever‐based energy harvester configuration is applied, and the optimal design of 3D printed energy harvesters is studied. The electromechanical behaviour of the device is represented by an analytical model for the estimation of the energy harvested from train‐induced bridge vibrations. A genetic algorithm constrained to geometry and structural integrity is used to solve the optimisation problem. The design flexibility and energy performance are maximised by 3D printing of the substructure of the harvester. An optimal device prototype with PAHT CF15 substructure is designed and manufactured for a real bridge in the Madrid‐Sevilla High‐Speed line. The prototype is experimentally validated under laboratory conditions. Finally, the performance of energy harvesting is evaluated from in situ experimental data measured by the authors. The results allow quantifying the energy harvested in a time window of five hours and twenty‐seven train passages. [ABSTRACT FROM AUTHOR]

The new Boca del Cerro Bridge is in southern Mexico at the exit of the Usumacinta River Canyon, in the city council of Tenosique in the state of Tabasco. A place of an extraordinary environmental value. This area is also a strategic crossing point, in which the actual Bridge over the Usumacinta River was built in 1950. It is a structure of extraordinary value, which is a milestone of the engineering of the time, with an upper arch of steel truss. The new Boca del Cerro Bridge has been designed, for the new Section 1 of the "Tren Maya" railway, parallel to the actual bridge. The solution adopted for the new bridge consists of a main span of double steel truss with double composite action (steel and concrete) and variable depth, that will be embedded in two lateral compensation spans of prestressed concrete. The new bridge has been designed in order to ensure a minimal "competition" and intrusion with the existing bridge and to enhance the beauty of the surrounding nature. The structural typology election has been conditioned by the advantages of its constructive process, that allows structure built‐up without riverbed support. To achieve this, the central span is planned to be erected by incremental cantilevers, carrying truss segments over the deck. [ABSTRACT FROM AUTHOR]

Herein, magnetoelectric microelectromechanical system (MEMS) cantilevers are investigated on basis of a TiN/AlN/Ni laminate derived from experimental sensors using finite‐element simulations. With the anisotropic ΔE effect as an implication of the magnetocrystalline anisotropy, the lateral sensitivity of the sensor is studied for different nickel layer thicknesses and boundary conditions. It is found that above 60% of the cantilever length, the nickel is effectively not contributing to the sensor sensitivity anymore which is supported by the investigation of sensors with partial nickel coverage. The boundary condition of the magnetostrictive layer is found to affect the sensitivity of thick layers while it is negligible for thinning layers. Further investigations on basis of polycrystalline untextured nickel with slightly preferred orientations reveal a stronger effect on thin layers than on thicker ones. It is found to arise from relatively large crystals in the high‐sensitivity region near the clamping of the sensor. For thicker polycrystalline layers, the ΔE effect reproduces a characteristic based mainly on the (110) and (111) orientations while the (100) orientation appears to be underrepresented. [ABSTRACT FROM AUTHOR]

Experimental investigation on the effect of static system and load arrangement on the shear resistance of beams with low amounts of shear reinforcement In this paper, an experimental investigation on the shear behaviour of beams with low amounts of shear reinforcement and different static systems is presented. Four simply supported beams under concentrated loads, ten cantilevers and three simulated continuous beams under uniformly distributed loads were tested. The shear reinforcement ratio was varied between 0 (without shear reinforcement) and 2.0 times the minimum shear reinforcement according to EC2. The test results show a significant influence of the static system and the loading type on the crack pattern and ultimate load of the beams tested. While a reinforcement level below the minimum shear reinforcement has almost no influence on the shear resistance of simply supported beams under concentrated loads, a very low shear reinforcement leads to a significant increase in the shear capacity of beams under uniform distributed loads. The crack pattern, however, remains unchanged compared to beams without shear reinforcement where shear failure is characterized by a single critical shear crack. The test results were also compared with design and standard specifications. The comparisons show possible improvement potentials in the currently applied models. [ABSTRACT FROM AUTHOR]

We have measured the elastic properties of live cells by Atomic Force Microscope (AFM) using different tip geometries commonly used in AFM studies. Soft 4‐sided pyramidal probes (spring constant = 12 and 30 mN/m, radius 20 nm), 3‐sided pyramidal probes (spring constant = 100 mN/m, radius 65‐75 nm), flat (circular) probes (spring constant = 63 mN/m, radius 290 nm) and spherical probes (spring constant = 43 mN/m, radius 5 μm) have been used. Cells (3T3 fibroblasts) having elastic moduli around 0.5 kPa were investigated. We found that cell measured stiffness shows a systematic dependence on tip geometry: the sharper the tip, the higher the average modulus values. We hypothesize that the blunter the tip, the larger the contact area over which the mechanical response is measured or averaged. If there are small‐scale stiffer areas (like actin bundles) they will be easier to pick up by a sharp probe. This effect can be seen in the wider distribution of the histograms of the measured elastic moduli on cells. Furthermore, non‐linear responses of cells may be present due to the high average pressures applied by sharp probes, which would lead to an overestimation of the Young's modulus. Pressure versus contact radius simulations for the different tip geometries for a 0.5 kPa sample suggested similar average pressure for Bio‐MLCTs, PFQNM and cut tips, except spherical tips that showed much lower average pressure at the same 400 nm indentation. However, real data of the cells suggested different results. Using the same indentation depth (400 nm), PFQNM and Bio‐MLCTs showed similar average pressure and it decreased for cut and spherical tips. The calculated contact area at 400 nm cell indentation, using the obtained apparent Young's modulus for each tip geometry, showed the following distribution: Bio‐MLCTs < PFQNM < cut << spherical. In summary, tip geometry as well as average pressure and tip‐sample contact area are important parameters to take into account when measuring mechanical properties of soft samples. The larger the tip radius, the larger the contact area that will lead to a more evenly distribution of the applied pressure. [ABSTRACT FROM AUTHOR]

The modal analysis and seismic response of a vibrating cantilever, with or without tip mass and rotary inertia, are investigated in this study using a shear deformable beam model and including the effect of vertical load. Based on existing approaches, an original method is proposed that does not use fourth‐order uncoupled equations to determine modal deflection and rotation. In fact, the approach presented herein transforms the second‐order coupled system into a first‐order system which can be solved more easily using matrix algebra and Laplace transform. Furthermore, the proposed form allows a straightforward demonstration of orthogonality conditions, that is, the problem is self‐adjoint, and the solution in the case of forced response using modal superposition. In addition, even if the solution presented herein is applicable only to the cantilever with a tip mass and rotary inertia, the scope is general, and the approach can be applied to shear deformable beams with other boundary conditions. Finally, the seismic response by modal superposition is shown, and some examples are proposed and discussed for the case of uniform or continuously varying cross‐sectional properties. [ABSTRACT FROM AUTHOR]

In the present work, an FE formulation using the zig‐zag hypothesis is developed for cantilever sandwich plates with viscoelastic care layer. Both viscoelastic and elastic layers of sandwich structures are considered based on the first‐order shear deformation theory to achieve higher accuracy. The FE simulation is validated by a frequency and loss factor analysis of sandwich plate. Furthermore, the damping characteristics and transient response of the cantilever sandwich plates are systematically studied. [ABSTRACT FROM AUTHOR]

Ongoing developments in nanotechnology demand higher spatial resolution and thus, higher amplitude sensitivity in Atomic Force Microscopy (AFM). In this work, active cantilevers with integrated sensor and actuator systems are parametrically excited using a novel, analog feedback circuit. With that it is possible to adapt the strength and sign of a cubic nonlinearity which provides a bound to the amplitudes in resonance operation. The system response shows steeper resonance curves and therefore higher amplitude sensitivities compared to forced excited cantilevers. Theoretical findings are validated experimentally. [ABSTRACT FROM AUTHOR]

Uniaxially stretched poly(l‐lactide) (US‐PLA) films display shear piezoelectric properties of interests for smart applications. However, the measurement of these properties is quite challenging and a simple technique based on bimorph cantilevers is here used. This technique is validated with commercial piezoelectric poly(vinylidene fluoride) (PVDF) films. A piezoelectric coefficient d31 close to 19 pm/V is then obtained with a precision close to 5% and a good accuracy to expected values. For US‐PLA films made by extrusion—machine‐direction orientation, shear piezoelectric coefficients d14 up to 5.9 pm/V are found. Relevant trends can be captured but a low precision on d14, close to 10%, is highlighted. This behavior is probably related to film thickness heterogeneities arising from the extrusion processing at the laboratory scale. Piezoelectric voltage coefficients (g14) and electromechanical coupling coefficients could be also easily obtained with additional measurements of the dielectric permittivity and mechanical compliance. Outstanding g14 coefficients up to 320 mV.m/N are confirmed for US‐PLA films with a precision close to 20%. The bimorph cantilever technique consequently represents a simple and reliable technique to evaluate piezoelectric properties of soft materials, in particular shear piezoelectric properties of US‐PLA films for future developments and optimizations at the pilot scale. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the fracture load and stress magnitude of different retainer designs of minimally invasive cantilever resin‐bonded fixed dental prostheses (RBFDPs) after artificial aging. Materials and methods: Fifty caries‐free human mandibular molars were prepared as abutments for cantilever fixed dental prostheses using different retainer designs: one wing (OW), two wings (TW), inlay ring (IR), lingual coverage (LC), and occlusal coverage (OC). Computer‐aided design and computer‐aided manufacturing were used for milling the RBFDPs using fiber‐reinforced composite (FRC), and the restorations were adhesively bonded. The specimens were then subjected to thermomechanical aging and loaded until failure. The 3D finite element analysis (FEA) was performed with five models of retainer designs similar to the in vitro test. Modified von Mises stress values on enamel, dentine, luting resin, and restorations were examined. Data were analyzed with Kruskal–Wallis and Mann–Whitney U tests (p < 0.001). Results: A statistically significant difference (p < 0.001) was found between all groups except between IR and LC and between OW and TW designs, with the highest mean failure load detected for OC (534.70 N) and the lowest detected for OW (129.80 N). With regard to failure mode, OW, TW, and LC showed more incidences of favorable failure patterns than IR and OC designs. FEA showed that FRC transmitted low stresses in tooth structure and high stresses to the luting resin. Conclusions: LC and OC designs can be used to design cantilever RBFDPs in premolar area. IR design transmitted more stresses to the tooth structure and resulted in 30% catastrophic failure. OW and TW were below the normal occlusal force and should be carefully used. [ABSTRACT FROM AUTHOR]

Purpose: The anterior‐posterior spread concept is relied upon to understand the bioengineering aspects of cantilevers in fixed complete denture prostheses. This concept is not evidence‐based. With no other category existing in contemporary implant dentistry, this conventional anterior‐posterior spread concept may have limited more precise and accurate biomechanical analysis. This paper aims to validate a scientific rationale for utilizing this new prosthesis‐implant arch area ratio instead of the preexisting anterior‐posterior spread concept. Materials and methods: Utilizing the preexisting mathematical principle of "Heron's formula," enabling the calculation of the area of a triangle with three known lengths and no angular information, a new prosthesis‐implant arch area ratio is introduced through algebraic derivation. Geometrically, three different sections of prosthetic cantilevers are defined as: (1) anterior cantilever; (2) lateral cantilever; (3) posterior cantilever. The prosthesis‐implant arch area ratio is defined as the prosthesis arch area (anterior, lateral, or posterior cantilever) divided by the sum of the platform arch area and the selected prosthesis arch area. As a proof‐of‐concept experiment, fifteen different laboratory cast arches (n = 15) were chosen; theorized four implant platforms were referenced from the conventional anterior‐posterior spread ration of 1:1.5, followed by calculating platform arch area and prosthesis arch area using Heron's formula. Then, three different horizontal arch width ratios (1:1, 1.25:1, and 1.5:1) under the constant linear height ratio of anterior‐posterior spread (1:1.5) were drawn to assign different experimental groups of prosthesis arch area on each patient scenario, followed by cantilever comparison combining all ratio values (n = 45). One‐way ANOVA and Tukey's post hoc multiple comparison tests were used for statistical analysis. Results: One‐way ANOVA revealed statistical differences of all prosthesis‐implant arch area ratios on each cantilever group; anterior cantilever, F(2, 42) = 8.326, p = 0.0009; lateral cantilever F(2, 42) = 43.92, p < 0.0001; posterior cantilever, F(2, 42) = 26.66, p < 0.0001, as well as cantilever's comparison, F(2, 132) = 240.8, p < 0.0001. Tukey's post hoc test showed a statistically significant ascending trend of prosthesis‐implant arch area ratio as the horizontal width ratio increases. Interestingly, the posterior cantilever had the greatest prosthesis‐implant arch area ratio. Conclusions: Compared to the preexisting anterior‐posterior spread concept, a new prosthesis‐implant arch area ratio seemed to be a more categorized, geometric, and perceptive modality of assessing the prosthetic cantilever in a full‐arch implant‐supported prosthesis, allowing a more systematic indexing of different full‐arch implant clinical scenarios with greater specificity and consistency. [ABSTRACT FROM AUTHOR]

To further our understanding of failure in thermoplastic‐based composite rods, the mode I‐governed cohesive zone model parameter of a basalt fiber reinforced polypropylene composite rod is evaluated. The relations between stress and strain, the maximum normal traction and final separation displacement are examined using a transverse tensile test method. The measured traction is verified by three‐dimensional finite element analysis of rod‐shaped double cantilever beam specimens. The numerical results show the close relation between the crack length and cube root of compliance, and yields a representative value of the mode I‐governed critical fracture energy. [ABSTRACT FROM AUTHOR]

This report presents testing of a prototype cantilevered liquid-nitrogen-cooled silicon mirror. This mirror was designed to be the first mirror for the new soft X-ray beamlines to be built as part of the Advanced Light Source Upgrade. Test activities focused on fracture, heat transfer, modal response and distortion, and indicated that the mirror functions as intended. [ABSTRACT FROM AUTHOR]

Background: The mechanical properties of hair treated with styling ingredients is an important aspect to determine if products will be efficacious when used by the consumer. Measurement techniques have been proposed in earlier work; however, these are mostly aimed at hairspray systems and not the myriad of styling products available to the modern‐day consumer. Aim: In this article, experimental and data analysis guidelines are proposed for the evaluation of styling ingredients using a three‐point cantilever bending technique. Most of the experiments were carried out on polysaccharide‐based ingredients—guar hydroxypropyltrimonium chloride (Guar HPTC) and cassia hydroxypropyltrimonium chloride (Cassia HPTC)—to establish basic characterization concepts of the polymer‐fiber assemblies. Methods: A three‐point cantilever bending technique was developed using a texture analyzer housed in a temperature and humidity‐controlled chamber. Scanning electron microscopy (SEM) studies were conducted to monitor the fracture mechanics of polymer‐fiber assemblies. Results: Fundamental studies were carried out to determine the effect of concentration, molecular weight (MW), and chemistry of the polysaccharides on the calculated indices, which characterize the stiffness, flexibility, elasticity, and plasticity of the treated hair. Experiments were conducted in a controlled temperature and humidity environment, which allowed us to monitor the behavior of the polymer‐treated hair from 40–90% RH. Studies were also conducted on polymer blends and conventional styling polymers to provide guidance of the performance of naturally‐derived polymers to their synthetic counterparts. Conclusions: A detailed description is provided for a user‐friendly, quick method to measure the mechanical properties of styling ingredients on hair. We provide guidelines for three‐point cantilever bending tests of straight hair tresses treated with conventional and naturally‐derived styling polymers. Indices were developed to characterize the force‐distance curves and were designated as E1, F1, position of F1, post‐fracture gradient, toughness, E10/E1, and F10/F1. These indices provide an overall characterization of the stiffness, flexibility, elasticity, and plasticity of polymer‐treated hair. [ABSTRACT FROM AUTHOR]

Achieving broadband energy harvesting at low frequencies is a difficult area of research today. To solve the aforementioned problems, herein, a nonlinear sickle‐shaped cantilever beam piezoelectric energy harvester (S‐PEH) for wind energy harvesting is proposed. It has a high‐voltage output in the wind speed range of 5.37–18.23 m s−1. The S‐PEH is consists of a collector and a transducer. The collector converts wind energy into rotating mechanical energy and excites the transducer by means of magnetic coupling, thus realizing the conversion of mechanical energy to electrical energy. The special structure of the transducer's sickle‐shaped cantilever beam type can effectively harvest wind energy in low‐frequency environment and broaden the range of harvesting wind speed in high voltage. The structure and principle of S‐PEH are analyzed by theory and simulation and are experimentally verified. The results show that when the magnet on the rotor is 15 mm away from the magnet of the piezoelectric sheet, the transducer angle is 90°, the load resistance is 100 kΩ, the voltage of the blower is kept at 120 V, and the system has a maximum power of 563 μW. Moreover, it can successfully make low‐power electronics work. [ABSTRACT FROM AUTHOR]

Background: Treatment of edentulous patients with implant‐supported over‐dentures improves denture's retention and stability. Published data concerning implant‐supported overdenture with cantilever bars that claimed that can affect the survival and bone loss of implants are scarce. Purpose: The purpose of this study was to evaluate 5‐year clinical performance of mandibular implant‐supported over‐dentures with different attachment systems. Materials and methods: In this retrospective study, 103 patients who had received mandibular over‐dentures supported by two implants were evaluated in a 5‐year follow up. Studied groups were patients with Spherblock ball attachment (58 patients), Dolder bar with cantilever (36 patients), and Locator attachment (9 patients). Marginal bone‐loss around implants, prosthetic complications, soft tissue status of the implants (gingival index, plaque index, pocket depth, and bleeding on probing) were used to compare studied groups. Visual Analogue Scale (VAS) criteria was used to assay patient's satisfaction. One‐way ANOVA, Scheffe, Kruskal–Wallis, Mann–Whitney, and Fisher's exact tests, were used for the data analysis (α = 0.05). Results: One hundred and three patients (46 male, 57 female, mean age 64.7 ± 8.6) with 206 implants (Strauman) were studied. The implant survival rate was 100% with mean bone loss of 0.22 mm around implants in 5 years. Prosthetic complications including attachment wear and denture fracture occurred more often with ball attachments. The number of attachment replacement, and post insertion appointments were significantly less in patients with bar attachments (p < 0.05). Pocket depth and gingival index were less in the ball attachment (p < 0.05). Conclusion: Mandibular overdenture supported by two implants can be considered a successful treatment in edentulous patients. The frequency of prosthetic complication is higher in unsplinted than splinted superstructures. [ABSTRACT FROM AUTHOR]

Piezoelectric vibration suppression technology (PVST) utilizes the inverse piezoelectric effect of piezoelectric materials to suppress the vibration of mechanisms through stress or strain. Cantilever beam, the most widely used mechanical structure, is trapped with the forced and redundant vibration while working which is the hot spot for both academia and industry. This article presents a comprehensive review of the dynamic model via three aspects. From the viewpoint of piezoelectric materials, it is most concerned about the influences of the materials, installation, and operating characteristics of the piezoelectric actuator on the performance of the actuator. Furthermore, this article summarizes and analyzes the existing control system and filtering method from the perspective of quick response and effective suppression. As a consequence, this article summarizes and analyzes the current status and problems of PVST of the cantilever beam, and points out that the PVST has the problems of small size, simplified model, and lack of experiment. It points out that PVST of cantilever beam should be developed in the direction of larger size, high precision, and engineering application. This article systematically summarizes and analyzes the research status and existing problems of PVST in cantilever beam structures for the first time. [ABSTRACT FROM AUTHOR]

Background: Current evidence about long‐term survival of all‐ceramic implant‐supported cantilever fixed dental prostheses (cFDP) is limited. Purpose: To evaluate the survival and complication rates of all‐ceramic and metal–ceramic implant‐supported cFDPs located in anterior and posterior sites, under consideration of risk factors. Methods of study: The retrospective analysis compared an experimental group (75 implant‐supported cFDPs among 48 patients [mean age 60.47 ± 9.25 years; 21 men]; mean observation period 3.56 years) with a control group (300 implant‐supported non‐cantilever FDPs [ncFDP] among 241 patients [mean age 62.85 ± 10.72 years; 109 men]; mean observation period 7.25 years). Kaplan–Meier estimates were used to describe the long‐term survival and success of both groups. Log‐rank tests were used for group comparisons. Mixed‐effects Cox proportional hazards regression models were used to examine the effects of restoration‐ and site‐specific risk factors. A random intercept was included in the models to take multiple FDPs per patient into account. Results: Five‐year cumulative survival until loss of restoration was 97.1% (95% confidence interval [CI] 0.93–1.00) for cFDPs and 97.0% (95% CI 0.95–0.99) for ncFDPs. Ten‐year survival was 93.7% (95% CI 0.86–1.00) for cFDPs and 92.8% (95% CI 0.87–0.98) for ncFDPs, no difference between the survival curves of these groups was observed. Success differed between cFDPs and ncFDPs (pLog = 0.002), zirconia and metal frameworks (pLog < 0.001), and provisional and definitive cements (pLog = 0.025). The effects of the variables "framework material" and "attachment method" were confirmed in a mixed‐effects Cox regression model. Loss of retention was the predominant complication for both cFDPs and ncFDPs and usually affected provisionally cemented FDPs. Conclusions: cFDPs do not differ from ncFDPs with regard to long‐term failure, whereas additional complications were higher for cFDPs. Fewer complications were observed for zirconia frameworks without occlusal veneers and definitive cemented FDPs. Clinical trial registration: the trial has no registration number because it commenced before January 31, 2017. [ABSTRACT FROM AUTHOR]

The unsteady bending problem of a cantilever elastic‐diffusion homogeneous orthotropic Bernoulli–Euler beam is considered, taking into account the relaxation of diffusion fluxes. The solution to the problem is sought using the method of equivalent boundary conditions. For this, an auxiliary problem is additionally considered. The solution to the auxiliary problem is obtained using the integral Laplace transform in time and the trigonometric Fourier series expansions in spatial coordinates. Next, relations are constructed connecting the right‐hand sides of the boundary conditions of the original and the auxiliary problems. These relations represent a system of Voltaire integral equations of the 1st kind. This system is solved numerically using quadrature formulas. The limit transitions to the static problem of elastic diffusion, as well as to the unsteady elastic problem for a cantilever beam, are investigated. Using a three‐component material as an example, a numerical study of unsteady mechanical and diffusion fields interaction in an orthotropic beam is done. The calculation results are presented in the form of graphs. They show the time and coordinate dependencies of the sought displacement fields and components concentration increments of the continuum. At the end of the publication, the main conclusions about the coupling effect of the stress–strain state and mass transfer in the beam are represented. [ABSTRACT FROM AUTHOR]

The stiffness and hysteretic response due to mechanical and thermo‐mechanical cycling have been studied in plasma‐sprayed yttria‐stabilized zirconia (YSZ). Mechanical cycling of free‐standing cantilevers of YSZ shows that the progressive decrease in stiffness is accompanied by monotonic increase in hysteretic energy dissipation per cycle and a permanent ratcheting displacement of ∼20 nm/cycle. Below a critical stress, it varies from coating to coating, ratcheting accompanied by a slow decrease in stiffness does not lead to failure even after ∼1000 cycles. In contrast, at higher stresses, the rates of ratcheting and decrease in stiffness increase rapidly, leading to the nucleation of macrocracks that lead to fracture failure. Prior thermal cycling of coatings on Inconel substrate up to 700°C, which induced an estimated cyclic thermal stress of ∼35 MPa, led to a pronounced reduction in stiffness and mechanical cycling life. During bending, damage accumulates in the tension side of the cantilever and the volume going through the compression cycle remains relatively undamaged. [ABSTRACT FROM AUTHOR]

This paper evaluates the capabilities of the recently developed CF20 cohesive fatigue model, which can predict crack initiation as well as the rates of crack propagation by relying on intrinsic relationships between a stress‐life diagram and its corresponding Paris law. The model is validated here using a partially reinforced double cantilever beam (R‐DCB) benchmark proposed in literature. The two parameters needed for the CF20 cohesive fatigue model were obtained by performing preliminary analyses of a conventional DCB. The analysis results indicate that the CF20 cohesive fatigue model can accurately reproduce the complex evolution of the delamination observed in the R‐DCB. Highlights: A 3D benchmark is analyzed using the mixed‐mode CF20 cohesive fatigue formulation.The parameters of the model are obtained from experimental results of DCB specimens.The model predicts crack growth rate and delamination shape changes during propagation.A parametric study illustrates the precision needed to accurately predict the final delamination length. [ABSTRACT FROM AUTHOR]

An integrated opto‐mechanical cantilever sensor with a rib waveguide is reported in this paper. The device consists of a rib waveguide cantilever with buried waveguides on silicon. The rib cantilever is introduced to match better with the buried waveguide, further for increasing the interface coupling efficiency. With this configuration, single‐mode operating can be achieved in transverse direction without decreasing the width of optical waveguide cantilever. The system sensitivity is 1.1 μm–1 which is increased by about 21%, compared with the conventional structure. [ABSTRACT FROM AUTHOR]

A simple method of measuring Mode I fracture toughness, KIC, of glass using the double cantilever beam (DCB) geometry is presented. An inert atmosphere is created at the crack tip to prevent subcritical crack growth and enable "pinning" the crack while the specimen is loaded to failure. This was achieved experimentally using liquid toluene or a glovebox with dry argon. KIC values measured by this method showed good agreement with published literature values for selected glasses. Applicability of the analytical stress intensity factor solution based on crack length, crack front curvature, and the height of the crack guiding groove are confirmed through experimental data and finite element analysis. The experimentally observed crack front curvature, which leads near the edges for small groove heights and leads in the center for larger groove heights, is predicted from the geometry of the DCB specimen for a linear elastic solid through finite element modeling. [ABSTRACT FROM AUTHOR]

Shear capacity of prestressed beams subjected to uniformly distributed load An experimental study on the influence of a centric prestressing on the shear capacity of RC‐beams without shear reinforcement was conducted. The experimental program consisted of twelve simply supported and cantilever prestressed beams under uniformly distributed loads. The results have shown significant differences of the influence of the prestress force on the shear capacity with regards to different M/V‐combinations in the shear span. The increase of shear capacity due to prestressing is for the cantilever beams considerably smaller than that of the simply supported beams. In addition, a nonlinear FE‐simulation was performed. Based on the experimental results and the conducted parametric FE study the enhancement factor of the shear capacity with respect to the centric prestress can be quantified for different static systems and loading configurations. [ABSTRACT FROM AUTHOR]