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El bambú es considerado como una materia prima muy importante para los países en vías de desarrollo, pues combina levedad con una elevada resistencia mecánica. Hasta ahora no se conoce adecuadamente el comportamiento del material cuando es sometido a los ensayos de caracterización mecánica. En este trabajo se buscó evaluar probetas de bambú (Guadua angustifolia) sometidas al ensayo de compresión simple. Se utilizó la técnica de moiré de sombra para mapear las deformaciones de las probetas en función de la cantidad de nudos presentes en ella (0, 1 ó 2). Los resultados obtenidos evidenciaron la adecuación de la técnica utilizada, permitiendo observar la distribución de las líneas de iso-deformación en el bambú. Abstract Bamboo is considered an important raw material in developing countries because its physical characteristics associate lightness with high mechanical resistance. However its behavior obtained from mechanical tests is not yet well defined. This research work had the objective of evaluating bamboo (Guadua angustifolia) testing specimens under simple uniaxial compression loading. Shadow moiré optical methods had been employed to generate deformation mapping as function of knots (0, 1 or 2). Obtained results indicate that the technique is well adequate in generating iso-deformation contour lines in bamboo specimens.

A method for identifying a dot-matrix hologram composed of grating dots with different fringe orientations is proposed. Two neighboring grating dots, Dot 1 and Dot 2, are selected. The intersection angle between the two sets of fringes of the two grating dots must be smaller than a threshold angle, e.g., 50 deg. The overlapping region of Dot 1 and Dot 2 can show a moiré pattern composed of many stripes. Some of the stripes contain the same fringe orientation as that of Dot 1, some of the stripes contain the same fringe orientation as that of Dot 2, and some of the stripes contain special fringe orientations different from those of Dot 1 and Dot 2. The stripes which contain special fringe orientations are called transition stripes here, and the number of transition stripes (transition stripe number) is used to identify Dot 1 and Dot 2. Because the transition stripe number for a dot pair is sensitively affected by the distance between the dot pair and the grating brightness distributions of the two dots, it is difficult to correctly reproduce the transition stripe numbers for the grating dot pairs on a dot-matrix hologram, i.e., counterfeiting the hologram is not easy. [ABSTRACT FROM AUTHOR]

In the present work, the production of digital holographic moiré-like patterns in a well-controlled digital Fourier transform holographic experiment is reported, and this technique is then applied to profilometry. A simple implementation of the digital Fourier transform holographic setup is used to produce these interference patterns. This setup allows us to control certain parameters, namely the incident angle of the reference beams and the spatial frequency of the moiré-like patterns. These digital moiré-like patterns could have promising applications in relevant optical interferometric fields such as profilometry, as demonstrated here, along with other industrial optomechanical applications. [ABSTRACT FROM AUTHOR]

Autostereoscopic displays based on lenticular arrays have reduced resolution in the horizontal direction with respect to the vertical due to the distribution of the horizontal pixels between the different views. One known method is to use a slanted lenticular array in order to increase horizontal resolution at the expense of the vertical. In this paper, we propose a different approach to circumvent the displayed resolution limitation by taking advantage of the lower acuity of the eye to chroma than luma. This is done by downsampling the interlaced multiview display image at the color subpixel level. The chromatic information is in effect subsampled in the horizontal dimension (assuming a vertically arranged subpixel structure of the display), while enhancement of luma resolution is achieved. By appropriate slanting of the lenticular so as to minimize Moiré effects, the chroma is on average sampled evenly over the different views; therefore, chromatic distortion is also minimized. The vertical sampling rate is not decreased in this method; therefore, the total perceived light field resolution is enhanced. We demonstrate an example with an increase in number of views by 40% for a given lenticular and display setup. [ABSTRACT FROM PUBLISHER]

How Mama met Dada. A double image, a double identity; an enigmatic face as a two-source interference pattern in a ripple tank. A furry moire and a radiant gaze (Man rays? Fay rays?);a coy wave, a fetching hat,constructed and destroyed, disguised and revealed, depending on your perspective. 'Lovingly Rrose Selavy alias Marcel Duchamp,' 1921, by Man Ray. [ABSTRACT FROM AUTHOR]

We report on strategies for characterizing hexagonal coincidence phases by analyzing the involved spatial moiré beating frequencies of the pattern. We derive general properties of the moiré regarding its symmetry and construct the spatial beating frequency ${\vec{K}}_{\text{moir{\'e}}}$ as the difference between two reciprocal lattice vectors ${\vec{k}}_{i}$ of the two coinciding lattices. Considering reciprocal lattice vectors ${\vec{k}}_{{i}}$ , with lengths of up to n times the respective (1, 0) beams of the two lattices, readily increases the number of beating frequencies of the n th-order moiré pattern. We predict how many beating frequencies occur in n th-order moirés and show that for one hexagonal lattice rotating above another the involved beating frequencies follow circular trajectories in reciprocal-space. The radius and lateral displacement of such circles are defined by the order n and the ratio x of the two lattice constants. The question of whether the moiré pattern is commensurate or not is addressed by using our derived concept of commensurability plots. When searching potential commensurate phases we introduce a method, which we call cell augmentation, and which avoids the need to consider high-order beating frequencies as discussed using the reported $(6\sqrt{3}\times 6\sqrt{3}){R}_{{30}^{^\circ }}$ moiré of graphene on SiC(0001). We also show how to apply our model for the characterization of hexagonal moiré phases, found for transition metal-supported graphene and related systems. We explicitly treat surface x-ray diffraction-, scanning tunneling microscopy- and low-energy electron diffraction data to extract the unit cell of commensurate phases or to find evidence for incommensurability. For each data type, analysis strategies are outlined and avoidable pitfalls are discussed. We also point out the close relation of spatial beating frequencies in a moiré and multiple scattering in electron diffraction data and show how this fact can be explicitly used to extract high-precision data.

Structural components may contain cracks, and for these components a crack tip represents a highly singular stress. The evaluation of the associated strain gradient is difficult to achieve with experimental discrete methods. An efficient alternative are the optical techniques which are non-contact, and so delivering continuous information of the displacement fields and associated derivatives for strain evaluation. This paper describes some experimental methods to fully characterize the displacement field near a crack tip existing in flat plates. Three optical field techniques based on image analysis were used in the present work; respectively, Electronic Speckle Pattern Interferometry, Moiré Interferometry, and Digital Image Correlation. These methods allow different resolutions which can be adjusted according to the expected strain gradient. While the first method depends on the laser wavelength and position of the illumination sources, the second depends on the grating pitch and the last on the surface texture or painted speckle. Algorithms to derivate and filtering the displacement field are developed to compute the strain field and will be used for further works. [ABSTRACT FROM AUTHOR]

Using a ray tracing technique, we investigate the dependence of the moiré effect on the crossing angles between touch screen panels (TSPs) and display panels, the metal grid structures (spacing and width), and metal grid shapes (non-uniform and random grids). Of those design parameters, adjusting the crossing angle (∼45°), reducing the grid width (∼1 μm), and employing a random grid in the shape of irregular hexagon are found to suppress the moiré phenomenon to a great extent. We also provide the simulation scheme that can capture the moiré patterns observed experimentally and useful design guidelines for metal grids. [ABSTRACT FROM AUTHOR]

In this paper, we propose a precise and fast computational method for the simulation and analysis of moire patterns including a complex, large scale of films and a reflecting surface under illumination of an external ambient light source. This algorithm is based on convolution with superposition of the intensity profile which is transmitted from the optical layers and the point spread function. The computation time is shown to be much faster than that of the conventional ray-tracing algorithm. It was also considered of an optically equivalent system with no reflection surface layer in order to handle a non-sequential system containing a reflecting surface. [ABSTRACT FROM AUTHOR]

Metal mesh with low resistance characteristics offers lower RC loading in touch application and it also has an advantage at cost competition. However, employed in high-resolution LCDs easily suffers from moiré and pattern visibility or interference while mesh conflicted with pixel patterns. This article describes how to build up model and criteria to solve visual perception issue in high ppi (> 530 ppi) LCD application and at the same time apply in 3D Curved Automotive touch display application. [ABSTRACT FROM AUTHOR]

In this paper, a new approach is proposed for characterizing the surface roughness of woven fabrics. This approach is based on the fringe projection moiré techniques and analysis of the moiré pattern, which is caused by the interaction between the Ronchi grating and the periodic structure of a woven fabric. In this study, an image processing procedure was employed and a new parameter called the "roughness index" was defined for quantifying the surface roughness. The results obtained from the moiré technique were validated by a set of pair-comparison subjective tests. The proper correlation, with an average R-squared value of 0.9087, between subjective and objective tests confirmed the accuracy, correctness and efficiency of the new method. Statistical analysis of the roughness results clarified that the effect of fabric structural parameters such as the weave structure and weft density is significant in the confidence range of 95%. [ABSTRACT FROM AUTHOR]

To support the development of any system that includes the generation and evaluation of camcorder copies, as well as to provide a common benchmark for robustness against camcorder copies, we present a tool to simulate digital video re-acquisition using a digital video camera. By resampling each video frame, we simulate the typical artifacts occurring in a camcorder copy: geometric modifications (aspect ratio changes, cropping, perspective and lens distortion), temporal sampling artifacts (due to different frame rates, shutter speeds, rolling shutters, or playback), spatial and color subsampling (rescaling, filtering, Bayer color filter array), and processing steps (automatic gain control, automatic white balance). We also support the simulation of camera movement (e.g., a hand-held camera) and background insertion. Furthermore, we allow for an easy setup and calibration of all the simulated artifacts, using sample/reference pairs of images and videos. Specifically temporal subsampling effects are analyzed in detail to create realistic frame blending artifacts in the simulated copies. We carefully evaluated our entire camcorder simulation system and found that the models we developed describe and match the real artifacts quite well. [ABSTRACT FROM AUTHOR]

Computer generated holograms are often exploited to implement optical encryption schemes. This paper proposes the integration of dynamic visual cryptography (an optical technique based on the interplay of visual cryptography and time-averaging geometric moiré) with Gerchberg–Saxton algorithm. A stochastic moiré grating is used to embed the secret into a single cover image. The secret can be visually decoded by a naked eye if only the amplitude of harmonic oscillations corresponds to an accurately preselected value. The proposed visual image encryption scheme is based on computer generated holography, optical time-averaging moiré and principles of dynamic visual cryptography. Dynamic visual cryptography is used both for the initial encryption of the secret image and for the final decryption. Phase data of the encrypted image are computed by using Gerchberg–Saxton algorithm. The optical image is decrypted using the computationally reconstructed field of amplitudes. [ABSTRACT FROM AUTHOR]

By way of experiments and ray tracing simulations, we investigate the angular dependence of moiré fringes induced by metal grids of various shapes (e.g., rectangular, square, hexagonal, and random metal grids) for touch screen panels (TSPs). To quantify the moiré phenomenon, we have utilized the standard deviation (SD) calculated from the simulated ray distribution. The SD value is significantly decreased (i.e., the moiré phenomenon is substantially suppressed) with the rectangular and square metal grids when the crossing angle between the metal grid and a black matrix (BM) of display panels lies within the range between 20° and 60° . For the hexagonal metal grid, there appears a sharp dip corresponding to the minimum SD value every 30 rotation angle. However, the SD value is observed to be very high near the crossing angles at which a sharp dip occurs. Though no angular dependence arises and no moiré patterns appear with the random metal grid, yet the SD value is even higher due to point defects, compared with the rectangular and square metal grids. These results are in qualitatively good agreement with the experiment results observed with the naked eye. [ABSTRACT FROM AUTHOR]

Shadow deposition fabricated Pd nanowires with well-oriented crystalline axes on MgO(210) faceted templates, and high-resolution transmission electron microscopy was used to examine the growth of the Pd nanowires in the [001] direction. The plane-view transmission electron microscopy images show long moiré fringes in the [001] directions with some imperfections, while the diffraction patterns contain Pd spots. The [001] and [010] directions of the Pd lattices are in the same directions as those of MgO lattices, but their lattice constants differ by 7.6%. The high crystallinity of Pd nanowires likely originates from the low-density nuclei growth on the (100) facet on the MgO(210) face. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Moiré method in scanning transmission electron microscopy allows observing a magnified two-dimensional atomic column elemental map of a higher pixel resolution with a lower electron dose unlike conventional atomic column mapping. The magnification of the map is determined by the ratio between the pixel size and the lattice spacing. With proper ratios for the x and y directions, we could observe magnified elemental maps, homothetic to the atomic arrangement in the sample of SrTiO3 [0 0 1]. The map showed peaks at all expected oxygen sites in SrTiO3 [0 0 1]. [ABSTRACT FROM PUBLISHER]

Motivated by the recent excitement around the physics of twisted transition metal dichalcogenide (TMD) multilayer systems, we study strongly correlated phases of TMD heterobilayers under the influence of light. We consider both waveguide light and circularly polarized light. The former allows for longitudinally polarized light, which in the high frequency limit can be used to selectively modify interlayer hoppings in a tight-binding model. We argue based on quasi-degenerate perturbation theory that changes to the interlayer hoppings can be captured as a modulation to the strength of the moiré potential in a continuum model. As a consequence, waveguide light can be used to drive transitions between a myriad of different magnetic phases, including a transition from a 120 ∘ Neel phase to a stripe ordered magnetic phase, or from a spin density wave phase to a paramagnetic phase, among others. When the system is subjected to circularly polarized light we find that the effective mass of the active TMD layer is modified by an applied electromagnetic field. By simultaneously applying waveguide light and circularly polarized light to a system, one has a high level of control in moving through the phase diagram in-situ. Lastly, we comment on the experimental feasibility of Floquet state preparation and argue that it is within reach of available techniques when the system is coupled to a judiciously chosen bath., (© 2022 IOP Publishing Ltd.)

The Dual‐Cell LCD product contrast ratio is much higher than normal LCD product and comparable to OLED product. But because of moiré the special pixel design is needed. To enrich the product group and lifetime, after adjusting different refractive index and haze, multi‐function film was studied out for stacking two cells under mass production directly without any special pixel design. Therefore the larger size and higher resolution Dual‐cell LCD product such as 110 inch 8K can realize, and also the cost is lower as well. [ABSTRACT FROM AUTHOR]

This paper described the advanced process for Dual‐Cell LCD. Through the built‐in POL, Dual‐Cell structure of four glasses was simplified to three glasses. Key technologies were WGP on cell for middle polarizer, low temperature cell process, high alignment accuracy for main cell and sub array. The results showed that contrast was greater than 10,000, the moiré and H mura is invisible to the naked eye due to smaller 0.5mm gap between main cell and sub array(1.0mm gap for four‐glass dual cell), the high alignment accuracy(x, y≤5um, θ ≤0.005°) for main cell and sub array. [ABSTRACT FROM AUTHOR]

Facial attractiveness has long been argued upon varied emphases by philosophers, artists, psychologists and biologists. A number of studies empirically investigated how facial attractiveness was influenced by 2D facial characteristics, such as symmetry, averageness and golden ratio. However, few implementations of facial beauty assessment were based on 3D facial features. The purpose of this paper is to propose a novel cluster assessment system for facial attractiveness that is characterized by the incorporation of 3D geometric Moiré features with an adjusted fuzzy neural network (FNN). We first extract 3D facial features from images acquired by a 3dMD scanner. Seven Moiré features are employed to represent a 3D facial image. The FNN classifier, taking the Moiré features as the parameters, is then trained and validated against independently conducted attractiveness ratings. A number of diverse referees were invited and offered their attractiveness ratings over a five-item Likert scale for 100 female facial images. The proposed assessment presents a high accuracy rate of 90%, and the area under curve (AUC) computed from the receiver operating characteristic (ROC) curve is 0.95. The results show that the perceptions of facial attractiveness are essentially consensus among raters, and can be mathematically modeled through supervised learning techniques. The high accuracy achieved proves that the proposed FNN classifier can serve as a general, automated and human-like judgment tool for objective classification of female facial attractiveness, and thus has potential applications to the entertainment industry, cosmetic industry, virtual media, and plastic surgery. [ABSTRACT FROM AUTHOR]

Abstract: Linewidth and opening ratio (ratio of linewidth to period) are important parameters in characterizing micro-/nano-periodic and quasi-periodic structures. Periodic structures are conventionally characterized by the direct observation of specimens under a microscope. However, the field of view is relatively small, and only certain details can be acquired under a microscope. Moreover, the non-uniformity of the linewidth in quasi-periodic structures cannot be detected. This paper proposes a new characterization method for determining the linewidth and opening ratio of periodic structures based on Moiré fringe analysis. This method has the advantage of full-field characterization of the linewidth of micro-/nano-structures over a larger area than that afforded by direct observation. To validate the method, the linewidth of scanning electron microscope (SEM) scan lines was first calibrated with a standard grating. Next, a microperiodic structure with known geometry was characterized using this calibrated SEM system. The results indicate that the proposed method is simple and effective, indicating a potential approach for the characterization of gratings over large areas. This technique can be extended to various high-power scanning microscopes to characterize micro-/nano-structures. [Copyright &y& Elsevier]

Twisted bilayer graphene (t-BLG) has recently been introduced as a rich physical platform displaying flat electronic bands, strongly correlated states, and unconventional superconductivity. Studies have hinted at an unusual Z topology of the moiré Dirac bands of t-BLG. However, direct experimental evidence of this moiré band topology and associated edge states is still lacking. Herein, using superconducting quantum interferometry, we reconstructed the spatial supercurrent distribution in t-BLG Josephson junctions and revealed the presence of edge states located in the superlattice band gaps. The absence of edge conduction in high resistance regions just outside the superlattice band gap confirms that the edge transport originates from the filling of electronic states located inside the band gap and further allows us to exclude several other edge conduction mechanisms. These results confirm the unusual moiré band topology of twisted bilayer graphene and will stimulate further research to explore its consequences.2 topology of the moiré Dirac bands of t-BLG. However, direct experimental evidence of this moiré band topology and associated edge states is still lacking. Herein, using superconducting quantum interferometry, we reconstructed the spatial supercurrent distribution in t-BLG Josephson junctions and revealed the presence of edge states located in the superlattice band gaps. The absence of edge conduction in high resistance regions just outside the superlattice band gap confirms that the edge transport originates from the filling of electronic states located inside the band gap and further allows us to exclude several other edge conduction mechanisms. These results confirm the unusual moiré band topology of twisted bilayer graphene and will stimulate further research to explore its consequences.

A arquitetura das plantas é muito importante para estudos de genética, fotossíntese evapotranspi-ração, e relações máquina/plantas. Esta pesquisa teve o objetivo de desenvolver um novo método para gerar uma imagem tridimensional das plantas. Esta nova técnica pretende determinar a arquitetura de plantas através do método de moiré “phase shift”. A inovação está na utilização de grades defasadas por um ângulo de π/2 radianos entre elas. Uma câmera digital foi utilizada para capturar os padrões moiré, que gerará as imagens a serem processadas. O procedimento para a análise das imagens envolvem softwares como o Microsoft Powerpoint,Coreldraw and Idrisi. O uso de uma grade sinusoidas de grande definição e de luz colimadada, assim com uma câmera CCD de alta resolução, assim como a superposição da descontinuidade durante o procedimento de “desenpacotamento” evitaram a ocorrência de ruído satisfatoriamente, melhorando a qualidade das imagens. A determinação da altura gerou um mapa topográfico de um modelo de planta que foi baseado em técnicas de moiré optico. Os resultados obtidos revelaram grande potencial do novo método proposto para a determinação da arquitetura de plantas com alta precisão, a baixo custo e pouco dispêndio de tempo.

Abstract: We propose a method to get the phase and amplitude modes of an electrically driven spatial light modulator (SLM) device using the formation of moiré patterns. It is found to be a fast experimental method to visualize the complex amplitude of the SLM and it may be an excellent guide to find specific complex configurations of amplitude and phase. Experimental results and limitations of the proposal are presented using a reflective liquid crystal on silicon (LCoS SLM) modulator. With this method it has been found experimentally a phase-mostly configuration using only one polarizer, without an analyzer. [Copyright &y& Elsevier]

Moiré superlattice (mSL)-induced sub-bands in twisted van der Waals homo- and heterostructures govern their optical and electrical properties, rendering additional degrees of freedom such as twist angle. Here, we demonstrate the moiré superlattice effects on the intralayer excitons and trions in a twisted bilayer of MoS 2 of H-type stacking at marginal twist angles. We identify the emissions from localized and delocalized sub-bands of intralayer moiré excitons and show their electrical modulation by the corresponding trion formation. The electrical control of the oscillator strength of the moiré excitons also results in the strong tunability of resonant Raman scattering. We find that the gate-induced doping significantly modulates the electronic moiré potential; however, leaves the excitonic moiré confinement unaltered. This effect, coupled with variable moiré trap filling by tuning the optical excitation density, allows us to delineate the different phases of localized and delocalized moiré trions. We demonstrate that the moiré excitons exhibit strong valley coherence that changes in a striking nonmonotonic W-shape with gating due to motional narrowing. These observations from the simultaneous electrostatic control of quasiparticle-dependent moiré potential will lead to exciting effects of tunable many-body phenomena in moiré superlattices.

Abstract: Based on the projection moiré method and heterodyne interferometry, this study proposes an alternative method for reconstructing the surface profile of an object. Obliquely illuminating a linear grating with an expanding collimated light, a self-image of this grating can be generated and projected on the surface of the tested object. The grating fringes distorted by the surface profile are imaged on the reference grating to form the moiré fringes. These moiré fringes are then captured by a CMOS camera. If the projection grating moves with a constant velocity along the grating plane, each pixel of the CMOS camera records a series of sampling points of the sinusoidal wave. These sinusoidal waves behave like heterodyne interferometric signals. Hence, the accurate and stable phase distribution of the tested object surface can be obtained using the IEEE 1241 least-squares sine fitting algorithm and 2D phase unwrapping. Substituting the phase values into the derived equation, the surface profile of the tested object can be reconstructed. The experiments in this study verified the feasibility of this method, showing a measurement resolution of approximately 1.9μm. The proposed measurement method has the merits of both the projection moiré method and the heterodyne interferometry. [Copyright &y& Elsevier]

Abstract: In the present work dynamic moiré-like fringe patterns, produced by photorefraction with low spatial frequencies, applied for profile determination of small objects is proposed. Basically, a Fourier transform profilometry technique is developed for an automated profile determination. This means, as far as we know, a new experimental procedure that exploits the real time holographic two wave mixing in Bi12TiO20 crystal sample. Besides, the mainly advantages of this procedure are, comparatively to the classical fringe projection method using the Michelson interferometer, best fringe pattern contrast, less speckle noise, absence of noises produced by spurious reflections and, the most significant, a pure sinusoidal shape obtained by dynamic holographic moiré-like process using photorefraction. [Copyright &y& Elsevier]

This article is an account of a trans-European poetry-film project, Continental Drift, which consists of a system of mutating from one short film to the next via poetry. Its methodology is explained, along with a description of how the project, still in its initial stages, is progressing. The main theoretical notion that underpins the project is viewing translation as a key concept for understanding European identity. The article first explores a view of European history and culture from a translational perspective, before demonstrating how these ideas have informed how the project is structured and viewed. Finally, the term moiré, borrowed from physics, is introduced as a general cultural term, but specifically used here to facilitate an understanding of translation and poetry-film. [ABSTRACT FROM AUTHOR]

Abstract: An auto-focus system based on the moiré effect and a feedback control method is presented. First, a collimated laser beam passes through a focusing lens then falls incident on the surface of the sample. The deviation of the angle of the light reflected back is proportional to the defocus distance from the sample. The reflected light then passes through two spiral gratings, producing three types of moiré pattern which can be observed and recorded by a linear CCD. The defocus distance can be derived from the spiral angle in the moiré pattern. The results show that auto-focusing can be achieved by the moiré method for glass and mirror samples in a cycle time of less than 0.1s. [Copyright &y& Elsevier]

The article discusses the results of a study that examined the effects of diffusers with different characteristics on moiré and cross-talk in the system. The diffusers were inserted between the contact-type multiview three-dimensional (3D) imaging system's image display and the viewing zone-forming optics. The study showed that the diffusers are effective in moiré reduction but triggers an increase in cross-talk.

Iron-phthalocyanine (FePc) molecules have been adsorbed on a graphene sheet prepared on the Ir(111) surface. The FePc molecules are flat-lying on graphene, as determined by near-edge X-ray absorption fine-structure, constituting a sub-nanometer thick molecular array at the single-layer coverage. The flat FePc single-layer presents a weak interaction of the organic macrocycle with the graphene surface and Ir subsurface substrate. Further FePc deposition on top of the first flat single-layer determines a three-dimensional island growth with varying molecular orientation. [ABSTRACT FROM AUTHOR]

Abstract: Here, the interactions of C60 at the surface of pseudomorphic Ni/Cu(100) and Co/Ru(0001) thin films and its effect on film growth and morphology were determined using in-situ scanning tunneling microscopy (STM) and Auger electron spectroscopy (AES). The novel development of C60-metallic based nanosystems, such as C60 molecular junction transistors, hinges on our ability to understand the factors governing structural stability in these nanosystems and the nature of the bond interactions at the C60–metal interface. In this study, C60 deposited onto the Ni(100) film surface is observed to be fairly immobile and uniformly distributed across the Ni surface. On the Co(0001) film surface however, C60 mobility is observed to be severely limited in some regions and highly mobile in others dependent upon Co film surface reconstruction, resulting in a non-uniform distribution of C60 across the Co film surface. Despite the presence of C60 on the Ni surface, there is no obvious influence of the C60 on further Ni film growth. In contrast, during Co film growth, islands only nucleate and grow from step edges or locally around C60 molecules. The strength of the Co–C60 bond interaction appears stronger than the Co–Co bond on Co film terrace. Generally, the Ni and Co films both continue epitaxial film growth in the presence of molecular C60. AES results indicate the C60 molecules maintain their chemical integrity during growth. [ABSTRACT FROM AUTHOR]

This paper describes three different optical techniques for the measurement of in-plane displacements close to the crack tip which can then be used to determine the presence of crack closure in propagating fatigue cracks. Conventional temporal phase shifting moiré interferometry is described first, followed by an improvement to this technique, load sequence phase stepping, which allows data to be collected much more frequently during a load cycle. Finally, more recent measurements using digital image correlation are reported. Results from all three techniques are compared and the advantages and disadvantages of each approach are discussed. [ABSTRACT FROM AUTHOR]

Abstract: In this review, a critical look at the research progress of experimental solid mechanics in China for the past years is presented. Issues are discussed of the discovery and development of new fundamental methods and techniques versus performance benchmarking for many of their applications. Included herein are photoelasticity and various forms of modern photomechanics, acoustical techniques, image processing and videometrics, radial and spectrum techniques, and experimental mechanics on micro/nano scale. It is also noticed that both the ever developed instrumentation and specialized synthetical techniques have played important roles in advancing experimental mechanics in scientific researches and industrial applications. Finally, an attempt is made to look into the future of experimental solid mechanics with personal opinions offered on what the future trends will be for the researches in the field. [ABSTRACT FROM AUTHOR]

Abstract: Quantitative deformation analysis of micro-fabricated electromechanical systems is of importance for the design and functional control of microsystems. In this paper, two modified digital moiré processing methods, Gaussian blurring algorithm combined with digital phase shifting and geometrical phase analysis (GPA) technique based on digital moiré method, are developed to quantitatively analyse the deformation behaviour of micro-electro-mechanical system (MEMS) structures. Measuring principles and experimental procedures of the two methods are described in detail. A digital moiré fringe pattern is generated by superimposing a specimen grating etched directly on a microstructure surface with a digital reference grating (DRG). Most of the grating noise is removed from the digital moiré fringes, which enables the phase distribution of the moiré fringes to be obtained directly. Strain measurement result of a MEMS structure demonstrates the feasibility of the two methods. [ABSTRACT FROM AUTHOR]

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