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Action research methodologies are dynamic, as they often evolve with a group and are shaped by multiple contributions that can change over time. As researchers are embedded within this process, reflexivity is paramount to remain attuned to how they move with and shape the research. In search of a dynamic way of engaging with reflexivity in action research, this paper explores intra-active and diffractive theory and considers how diffracting reflexivities (Serra Undurraga 2021) can help researchers grasp a deeper understanding of their role in shaping the research process. This paper draws from a doctoral researcher’s experience navigating their reflexivity within an action research project to design sexuality education materials with young people in Aruba. Through its documentation of three multi-modal apparatuses, including doodling, audio/written journaling and blackout poetry, it offers a snapshot into creative methods for reflexivity and maps how their intra-actions go on to shape research practice. This paper contributes to the literature by providing insight into the ‘doing’ of reflexivity. It concludes that thinking with a diffractive lens and remaining curious to intra-actions are valuable tools for building a dynamic personal practice that compliments the emergent nature of action research methodologies. [ABSTRACT FROM AUTHOR]

Diffraction is a fundamental phenomenon that occurs when blast or shock waves pass over sudden discontinuous surfaces. It generates a complex flow field consisting of diffracted waves, expansion waves, slipstream, contact surface, and an unstable shear layer, in addition to emitting acoustic waves. In this study, we investigated the diffraction of a blast wave passing over a series of grooved structures with different aspect ratios and geometrical shapes (rectangular, circular, and triangular) using high-speed shadowgraph images. The blast wave Mach number considered in our investigation is 1.34. The grooves feature leading-edge geometrical variations such as rectangular, circular arc, and wedge shapes positioned at various lateral locations from the exit of the shock tube. The aspect ratios of the rectangular grooves vary from 0.33, 0.5, and 0.67. The circular and triangular grooves have an aspect ratio of 0.33. The trajectories and velocities of the primary vortex are calculated by tracking the location of the vortex in the shadowgraph images. Our observations revealed that a large portion of the incident blast wave is abducted inside the groove as the aspect ratio increases in rectangular grooves, resulting in better attenuation of the blast wave. The grooves, which have circular shapes, produced weaker diffraction, which resulted in delayed and weak primary vortex. The triangular grooves produced the strongest primary vortex and have the highest attenuation characteristics among other grooves. The strength and trajectory of the primary vortex formed over the grooves strongly depend on the aspect ratio and the curvature of the leading edge for a given Mach number. Vortices generated from rectangular and triangular grooves exhibit considerable strength and longevity. [ABSTRACT FROM AUTHOR]

Inspired by interviews conducted with scientists who primarily use participatory research forms, the article develops the concept of epistemic caring as a proposal for a participatory research practice that is sensitive for epistemological difference and the associated consequences. Based on the observation that participatory research has so far hardly been able to produce an equal co-constitution of knowledge, the article points out epistemological pitfalls that exist in it and analyses two specific concepts as examples of the risk of problematic epistemological and hegemonic tendencies sneaking into this kind of research practice with harmful consequences for the non-academic participants, that is: empowerment and participation/co-production. Following the recent debate on care in the Environmental Humanities and Karen Barad’s methodological thoughts on diffraction, the article reconceptualizes participatory research as a matter of care consisting of multiple care relations in order to be able to grasp the complex epistemic entaglements and intra-dependencies contained within it. Conceiving these relationships between academic and non-academic participants as an ecology of care themself helps to understand that they are fundamentally precarious and transformative and thus inherently ethical. [ABSTRACT FROM AUTHOR]

A general theory for solving electromagnetic diffraction problems with impenetrable/penetrable wedges immersed in/made of an arbitrary linear (bianistropic) medium is presented. This novel and general spectral theory handles complex scattering problems by using transverse equations for layered planar and angular structures, the characteristic Green function procedure, the Wiener–Hopf technique, and a new methodology for solving GWHEs. The technique has been proven effective for analyzing problems involving wedges immersed in isotropic media; in this study, we extend the theory to more general cases while providing all necessary mathematical tools and corresponding validations. We obtain generalized Wiener–Hopf equations (GWHEs) from spectral functional equations in angular regions filled by arbitrary linear media. The equations can be interpreted with a network formalism for a systematic view. We recall that spectral methods (such as the Sommerfeld–Malyuzhinets (SM) method, the Kontorovich–Lebedev (KL) transform method, and the Wiener–Hopf (WH) method) are well-consolidated, fundamental, and effective tools for the correct and precise analysis of electromagnetic diffraction problems constituted by abrupt discontinuities immersed in media with one propagation constant, although they are not immediately applicable to multiple-propagation-constant problems. To the best of our knowledge, the proposed mathematical technique is the first extension of spectral analysis to electromagnetic problems in the presence of angular regions filled by complex arbitrary linear media, thereby providing novel mathematical tools. Validation through fundamental examples is proposed. [ABSTRACT FROM AUTHOR]

This paper explores the different epistemologies that define the Professional Doctorate, paying close attention to how Postgraduate Researchers (PGRs) doing a Professional Doctorate reconcile academic and professional knowledge. Through a narrative exploration of the literature published since the first UK Professional Doctorates were awarded in 2000, the paper situates the Professional Doctorate within the confluence of the workplace, the profession and the university. From this stance, the paper explores distinct knowledge terrains between knowledge generated by Professional Doctorates in the context of application and knowledge generated in the context of disciplinary laws applied to sites of practice. The purpose of this discussion is to understand if, how and to what extent Professional Doctorates reconcile competing knowledge terrains. This study draws towards two broad conclusions. The first conclusion suggests that in the literature identified, the distinction between academic and professional epistemologies has little resonance. Instead of the dichotomous knowledge generated in the context of practice in contrast to knowledge generated in the context of disciplinary laws, Professional Doctorates were ensconced within several competing epistemologies. The literature identified focuses on impact and identity, concepts the study employs as lenses to guide a discussion. The paper thus views the process of reconciliation first through the lens of impact and then through the lens of identity. The investigation then draws a second conclusion: The epistemic landscape occupied by the Professional Doctorate is involved in a reconciliation of more significance that the putative academic and professional binary. The paper is compelled towards a diffractive re-reading of this academic-professional knowledge tension. This new reading allows a full recognition of both difference and mutual entanglement between knowledge generated in the context of practice and knowledge generated in the context of disciplinary laws. [ABSTRACT FROM AUTHOR]

Electrically tunable metasurfaces with pixel-level phase control are good candidates for dynamic manipulation of the beam direction in the terahertz band, which is a critical and highly desired technique for next generation communications. Yet the complex biasing, limited aperture and cross talk hinders its progress. In this study, we propose a magnetic-field-globally controlled metasurface for beam switching. The metasurface is composed of a bi-layer silicon metagrating on a magneto-optical substrate InSb. The beam direction is governed by two physical processes: the magnetically-controlled polarization and the polarization-controlled diffraction. By utilizing the circular dichroism and Faraday rotation effects in InSb, the metasurface can operate at two frequency bands. The beam is switched among four directions by properly choosing the magnetic field biasing and the frequency. This study offers a promising solution for beam management using magnetic field biasing and in a global manner. [ABSTRACT FROM AUTHOR]

From early 2020, as the spread of COVID-19 and related restrictions intersected with everyday lives and, inevitably, social research practices, the ability to act and continue research was a significant concern in the social research community. In a project aimed at supporting methodological responses to the pandemic context the authors ran a series of online knowledge exchange workshops. The invitation to participate suggested researchers convey recent times of their research experiences by drawing and presenting a river sketch. The paper critically engages with the research rivers by creating a new interference pattern of a new materialist approach combined with experiences and project artefacts. The compatibility of new materialism and qualitative inquiry is discussed. Through an analysis focussed on two of the rivers, the ways the research river activity entangled matter and meaning is examined and the paper shows how a new materialist understanding of exclusion transforms the ethical dimensions of researchers' methodological decisions. We conclude that research rivers produce particular forms of retrospective agency that highlighted affect throughout the pandemic and reframes the ethics for choosing and developing methods along an axis of inclusion and exclusion. [ABSTRACT FROM AUTHOR]

Techniques for producing fast Huygens–Fresnel–Kirchhoff digital holograms using kernel symmetry are studied. This study demonstrates non-linear behavior in computing time, as the sampled area changes with respect to the propagated diffracted area. Given the large amount of data involved in 3D object formation, symmetries are crucial in reducing the computational time. The evaluation of diffraction patterns is implemented to avoid redundant calculations while preserving the precision of the results. This algorithm decreases the required computing time depending on the symmetry of the axes, compared to direct calculation. Interestingly, the reduction in computing time relative to the number of symmetries is not linear. Computing time curves are presented. Some redundant computations are determined by the initial conditions of the object matrix, whether even or odd, along its x and y axes. Diagonal symmetries possess intrinsic redundancy along their axes. The rotation of the image must align with the rotation of the geometric coordinates in each section to ensure accurate calculations. [ABSTRACT FROM AUTHOR]

In this work we present a formalism based on scalar Green's functions to deal with electromagnetic scattering problems. Although the formulations of the Mie theory and Born approximations in terms of electromagnetic scattering are well known and relevant, they have certain disadvantages: complexity, computational time, few symmetries, etc. Therefore, the study with scalar Green's functions allows dealing with these problems with greater simplicity and efficiency. However, the information provided by the vector formulation is sacrificed. Nevertheless, different cases of electromagnetic scattering of dielectric media with different dimensions, geometries and refractive indices will be presented. Thus, we will be able to verify the capacity of this scalar method in predicting light-scattering problems. [ABSTRACT FROM AUTHOR]

Detection of earthquake precursors has long been a controversial issue with regard to its possibility and realizability. Here we present the detection of electromagnetic anomalous signals before large earthquakes using an observation network of very high frequency radio wave receivers close to major tectonic lines in Japan. The receivers are equipped with specifically designed narrowband filters to suppress noises and to detect extremely weak signals. We detected different types of electromagnetic anomalies before earthquakes around mountainous and coastal regions, where presence of electric charges is anticipated on the surface located in the middle of the radio wave paths near major tectonic lines in Japan. We use numerical electromagnetic wave analysis to show that when electric charges are present on a ground surface as a consequence of tectonic activity, the surface charges interact strongly with radio waves and eventually cause strong diffraction of the radio waves. The analysis was performed using the three‐dimensional finite‐difference time‐domain method with digital elevation models of the actual geographical landforms on a massively parallel supercomputer. The results confirm the consistent mechanisms of the electromagnetic precursors, which explains the anomalous electromagnetic signals observed by the authors before large earthquakes. Plain Language Summary: Possible electromagnetic precursors of earthquakes has been detected by observation networks placed near major tectonic lines in Japan. We have observed radio waves from many sources for several years, and anomalous electromagnetic diffraction has been considered as the precursors of earthquakes. We also consider the mechanism of the signals, and found that anomalous electromagnetic diffraction occurs shortly before earthquakes. The behavior of the radio wave has been confirmed also by various computer simulations. Key Points: A low‐noise high‐sensitivity technique is proposed to observe anomalous radio wave signals associated with earthquakesPossible electromagnetic precursors of earthquakes have been detected by observation networks placed near major tectonic linesLarge‐scale numerical analysis has suggested that anomalous diffraction is the mechanism of the electromagnetic precursors [ABSTRACT FROM AUTHOR]

Copyright of Journal of Marketing & Marketing Research / Pazarlama ve Pazarlama Araştırmaları Dergisi is the property of Pazarlama & Pazarlama Arastirmalari Dernegi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study used an optimal implant diffractive bifocal intraocular lens (IOL) made of a foldable hydrophobic acrylic polymer. The distinctive optical properties (refractive index of 1.55, abbe number of 41.91) of this polymer, the high refractive index of the polymer helps to focus light and increase the ray bending to form a good image, while the low water content of the polymer helps to prevent infections. ZEMAX-EE optical software, which produces results that are closer to the human eye, and a common metrics were used in this evaluation to assess the effectiveness of this IOL, such as the modulation transfer function (MTF), spot diagram and the behaviour of MTF field of view. These measurements were taken within the entrance pupil diameters of 1.5, 3 and 4 mm over a field of view of 20°, 30° and 40°. The results showed that the selected design and lens shape significantly improved and enhanced optical performance. [ABSTRACT FROM AUTHOR]

Copyright of Coal Geology & Exploration is the property of Xian Research Institute of China Coal Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study conceptualizes alpine skiing as a troubled and troubling leisure practice in the context of the Anthropocene. It employs a critical feminist new materialist lens and a diffractive methodology to unravel, critique, and undo the multifaceted more-than-human relations with snow and landscapes in alpine skiing. The study contends that alpine skiing is troubled by its capitalist, extractive, and exploitative relations with nature. Diffraction disrupts these relations by cutting through dualities and boundaries. Through diffractive vignettes of contaminating, collaborating, annihilating, and speculating, the findings illustrate the tensions and entanglement at the core of alpine skiing and how they matter for more-than-human relations. The study contributes by demonstrating how a diffractive engagement with leisure can be productive of troubling, caring, and thinking-with more-than-humans in hopeful futures beyond the Anthropocene. [ABSTRACT FROM AUTHOR]

The present study provides the analytical solution for magnetoelastic plane-wave diffraction by a rigid strip in an infinite orthotropic medium. The mathematical formulation of the considered model involves a mixed boundary value problem, which is solved by using the integral equation method. The contour integration technique has been used to establish the closed-form expressions of vertical diffracted displacement and normal stress. The deduced expressions of the vertical diffracted displacement and normal stress are matched with preestablished result through the special cases and serves the validation of the present study. The pattern of the diffracted displacement component in the considered medium, and its varying behavior with various affecting parameters, i.e., magnetoelastic coupling parameter, wave number, phase velocity of the propagating magnetoelastic wave, and distance, are computed numerically and delineated by means of graphical representation for orthotropic and isotropic materials. Moreover, the impact of anisotropy of the infinite medium has been unrevealed through comparative study, which is one of the achievements of the present work. Practical Applications: The diffraction of longitudinal magnetoelastic plane waves through a rigid strip in an orthotropic material holds significant applications across diverse engineering fields. In nondestructive testing (NDT), the understanding of wave diffraction patterns aids in the detection and characterization of defects or structural changes in orthotropic materials without causing damage. This knowledge is vital for structural health monitoring (SHM), allowing for the timely identification of damage, cracks, or alterations in material properties. Moreover, the insights gained from wave diffraction contribute to the design and optimization of magnetoelastic devices, including sensors, actuators, and transducers, enhancing their performance and sensitivity. In the realm of communication, the propagation of magnetoelastic waves through rigid strips in orthotropic materials is instrumental in designing efficient waveguides and communication devices. Additionally, the study of wave diffraction facilitates the development of magnetostrictive components for applications in robotics, medical devices, and automotive systems. Furthermore, the unique acoustic properties of orthotropic materials, influenced by magnetoelastic wave diffraction, contribute to the design and optimization of acoustic devices such as speakers and ultrasonic transducers. [ABSTRACT FROM AUTHOR]

Skepticism and critical inquiry play crucial roles in the scientific process, acting as safeguards against the "ad verecundiam" fallacy, where claims are accepted solely based on authority endorsement. This study thoroughly investigates Augustin-Jean Fresnel's challenge to Newton's corpuscular theory with his innovative wave theory of light. Supported by precise measurements and the "Fresnel integrals," Fresnel earned the Paris Academy of Sciences Prize in 1819. Despite staunch opposition from corpuscular theory proponents, his theory's validity was confirmed with Poisson's point paradox, where light waves from two sources interfere to create a bright spot in the center of a shadow, providing compelling evidence for the wave nature of light. This successful resolution of the paradox confirmed the validity of Fresnel's wave theory and contributed significantly to the acceptance of wave optics over the corpuscular theory. This conflict transcended a mere clash of explanatory models in the physics of light, prompting reflections on the nature of light, reality, and epistemological issues. Examining how Fresnel overcame challenges offers lessons on constructing scientific knowledge, emphasizing the importance of avoiding theory acceptance based solely on authority and focusing on empirical evidence and theoretical coherence. The case of Fresnel serves as a valuable example for teaching the history of science and understanding complex scientific evolution. Analyzing how Fresnel navigated challenges and opposition provides valuable insights into the development of scientific knowledge, emphasizing the intricate nature of scientific progress characterized by debates and efforts to gain acceptance. This study on Fresnel's groundbreaking wave theory of light not only illuminates the historical clash between competing scientific paradigms but also aims to contribute to modern science by emphasizing the enduring significance of empirical evidence and theoretical coherence in knowledge construction. Through an insightful exploration of Fresnel's triumph over challenges, we anticipate offering valuable insights that resonate with contemporary scientific methodologies, fostering a deeper understanding of the dynamic evolution of scientific thought.

Subject and Purpose. The sources of errors are identified that may arise in the course of terahertz-range measurements of the dielectric constant of weakly absorbent dielectrics, if performed within the surface plasmon resonance (SPR) technique. Possible ways are analyzed for reducing or fully eliminating such errors. Methods and Methodology. Specific details of applying the SPR method for dielectric constant measurements have been analyzed, with the aim of identifying the major factors that particularly affect the measurement accuracy. Results. It has been noted that in order to reduce the level of backlight interference (which may lead to blinding the receiver), it is expedient to make surface resonance records via frequency scanning. In that case the impact of the interference signal nonstationarity arising from the partial conversion of the surface wave energy into that of the volume wave, which occurs at the grating edges, is markedly lower than in the case of angular scanning. A mathematical expression has been derived which suggests a relation between scanning step sizes in angle and in frequency (for the angular and frequency scanning, respectively). As has been shown, a better measurement accuracy is achievable if the SPR is recorded as a function of frequency. Indeed, the frequency can be varied, with the use of familiar technologies, in steps of a much smaller size than such adopted for angular scanning. Errors in the above measurements can also arise if the resonance is excited on a grating whose Fourier spectrum contains many high-frequency components which carry a noticeable portion of the diffracted radiation energy. These energy losses can be greatly reduced if the SPR is excited on a grating whose profile involves the lowest number of spatial Fourier harmonics. Conclusions. The method suggested allows a significant reduction in the level of errors of the dielectric constant measurements in weakly absorbing dielectrics if the surface plasmon resonance effects are registered in dependence on the incident frequency, while the SPR is excited at a diffraction grating whose troughs-and-peaks profile is close to harmonical.

AbstractX-ray diffraction (XRD) is an analytical technique that has found several applications focusing on the identification of crystal structure, space groups, plane, and orientation, in addition to qualitative and quantitative phase identification, and polymorphism behavior. An XRD diffractogram pattern/Bragg’s peak can also provide valuable information that can be used for various food applications. While this review details the fundamental principles of XRD, the types of XRD systems, instrumentation, and the components thereof, the focus is to serve as a structured resource on explored applications of XRD in food, majorly revolving around food quality and safety. While recent studies relevant to the field are highlighted, leads for futuristic prospects are presented. With its unique approach, the XRD analysis can prove to be a rapid, robust, and sensitive nondestructive approach to food quality evaluation. Recent reports indicate its scope for nonconventional applications such as the assessment of 3D printability of foods, ice crystal formation, and screening food adulterants. Studies also highlight its scope to complement or replace conventional food quality testing approaches that involve the usage of chemicals, extensive sample preparation procedures, derivatization steps and demand long testing times. [ABSTRACT FROM AUTHOR]

In this paper we consider flexural-gravity waves propagating in a layer of water of constant depth limited by a vertical wall simulating a straight coastline. The water surface is covered with an elastic ice sheet of constant thickness. The ice sheet is split by one or two straight cracks parallel to the coastline, simulating the structure of land-fast ice with a refrozen lead. Analytical solutions of hydrodynamic equations describing the interaction of flexural-gravity waves with the ice sheet and cracks have been constructed and studied. In this paper, the amplification of the amplitude of incident waves between the shoreline and cracks was described depending on the incident angle of the wave coming from offshore. The constructed solutions allow the existence of edge waves propagating along the coastline and attenuated offshore. The energy of edge waves is trapped between the coastline and ice cracks. The application of the constructed solutions to describe wave phenomena observed in the land-fast ice of the Arctic shelf of Alaska is discussed. [ABSTRACT FROM AUTHOR]

The study conducted X-ray diffraction analysis on three-dimensional objects of arbitrary geometric shapes using computer modeling within the context of the Fresnel-Kirchhoff theory. Optimal parameters were deduced to produce high-quality images of the objects under study (distances from the source to the object and from the object to the detector, aperture dimensions, numerical calculation parameters, etc.). A method for generating three-dimensional models of the research objects was introduced, enabling the examination of structural formations with exceptional detail. An algorithm was devised to calculate diffraction images at various orientations of the research object. A method has been devised to reconstruct the shape and dimensions of three-dimensional samples using diffraction patterns obtained through the X-ray phase contrast technique. The study confirmed the complete alignment of these results with the constructed model of the three-dimensional objects. These findings hold practical value for developers of laboratory facility for three-dimensional analysis of materials using X-ray phase contrast methods. [ABSTRACT FROM AUTHOR]

Due to their unique properties, metal-organic frameworks (MOF-2) have demonstrated significant potential for various biomedical applications. In this research, a manganese-Larginine framework (MOF-2) was synthesized and characterized using techniques such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The MOF-2's antibacterial activity against selected bacteria was evaluated via the agar-well diffusion method, and it was found to be more effective against E. coli than S. aureus. Furthermore, the MOF-2's potential as an antioxidant was investigated using the spectrophotometric method against ABTS and DPPH free radicals, with the MOF-2 displaying higher antioxidant activity against DPPH. The obtained results indicate that the synthesized MOF-2 possesses potent antibacterial and antioxidant activities, making it a promising candidate for various biomedical applications. [ABSTRACT FROM AUTHOR]

In this paper, we present a numerical study of a two-layer fluid flowing around a vertical hollow cylindrical structure. We analyze the effect of two-layer fluid in the presence of hollow cylindrical structure in the surface and internal wave modes. We consider a hollow cylinder within a two-layer fluid wherein the upper fluid is bounded by a free surface above and the lower fluid is bounded by an impermeable solid below. A matched eigenfunction expansion and separation of variables method are used to obtain the diffracted velocity potentials in the identified domains. The obtained diffracted velocity potential gives us the wave elevation at the surface and the internal wave modes. We present the wave elevations with different parameters of the device in various wave modes of motion, including surface waves and internal waves. It is observed that in the surface mode, the free surface elevation is higher than the interface elevation and the free surface and the interface elevations are in same phase whereas in the internal wave mode, the elevation at the interface is greater than that at the free surface. [ABSTRACT FROM AUTHOR]

A small group (n = 11) of singers from the same community of musical practice in the UK participated in focus group workshops to reflect on their experiences of group singing in nature. The study found that group singing in nature was considered to be a (non-religious) spiritual practice that enhances participants' experience of both communitas and their connection to the natural world. Participants made an important distinction between singing with the earth – communing with the natural world in a more spiritual way – and singing for the earth, more political activity in response to local and global environmental issues. From a Posthuman perspective, diffraction – as both the physical and metaphorical process of exploring 'differences that matter' – is identified as an important concept for understanding how different routes to wellbeing can be mutually constitutive and intra-active. De-centring human experience by amplifying the co-constitutive role of other agencies like the natural world highlights the ontological and epistemological complexity of such experience. [ABSTRACT FROM AUTHOR]

Although encompassing a variety of research approaches, qualitative research in music education shares the assumption that reality is socially constructed; it takes this construction to be based on the specific perspective of the individual human; and it considers epistemology and ontology to be different fields of study. The posthuman theory of agential realism, on the other hand, argues that the world is becoming through intra-actions; it decentres the individual humanist subject; and it studies onto-epistemology – practices of knowing-in-being. Considering these fundamental differences, the quality criteria of qualitative research are not applicable to posthuman music education research. Nevertheless, posthuman research is concerned with the ethics of research and how to response-ably and ethically take part in the world's becoming. Thus, the emerging field of posthuman music education research must develop other ways of evaluating research beyond the quality criteria found in qualitative methodologies. This paper argues that diffraction – both as a physical and musical phenomenon and as a philosophical concept – might be a fruitful approach. By reading quality criteria diffractively through the agential realist concept of response-ability, it poses critical and creative questions, moving us towards evaluating the quality of posthuman music education research on its own terms. [ABSTRACT FROM AUTHOR]

We compared the impact of alumina doping on the structure of Al2O3–SiO2 amorphous thin films and bulk glasses using Raman spectroscopy and x‐ray diffraction. In both thin films and bulk glasses, the addition of Al2O3 is accompanied by an increase in the mean Si–O–T angle and an evolution of the ring statistics with a decrease in the proportion of small rings. We evidenced structural differences between sputtered films and fused bulk glasses. Sputtered Al2O3–SiO2 thin films are about 6%–7% denser than their equivalent Al2O3–SiO2 bulk glasses. This difference is mainly due to a change in ring statistics with the formation of small rings within the sputtered thin films. These structural differences in atomic structural organization highlight the impact of the synthesis conditions and open the door to further investigation of the structure–functional property relationships in sputtered Al2O3–SiO2 thin films. [ABSTRACT FROM AUTHOR]

In order to improve the accuracy of rockburst warning, it is necessary to accurately interpret the microseismic (MS) information obtained during the rockburst development process. However, the MS source location is very important for the interpretation of MS information, and the MS location method has an important impact on the location accuracy. To improve the location accuracy of MS sources, a location method considering diffraction in tunnel engineering is proposed. In this method, the shortest path length between the MS source and a sensor that does not cross the empty area of the excavated tunnel section replaces the straight path length between the MS source and the sensor for the location calculation, which can reduce the location error caused by propagation path length inaccuracy. To analyse the performance of this location method, a virtual MS source location simulation test and an in situ blasting point location test were carried out based on a tunnel project. The results show that the location method can well characterize the propagation path of MS source waves in a rock mass, thus making the location error smaller. During the in situ blasting point location test, the average absolute location error of point sources is approximately 8 m, and the average relative location error is approximately 6.72%. The location results can well meet the requirements of rockburst MS monitoring for location accuracy. [ABSTRACT FROM AUTHOR]

The investigation of iron under high pressure and temperatures is crucial to understand the Earth's core structure and composition and the generation of magnetic fields. Here, we present new in situ XRD measurements for iron in an off-Hugoniot state by laser-driven ramp compression at pressure of 200–238 GPa. The lattice parameters for the hexagonal (hcp)-Fe phase and the c/a ratios were obtained to compare them with previous static and dynamical data, which provides the direct confirmation of such parameters via the different compression paths and strain rates. This work indicates that laser ramp compression can be utilized to provide crystal structure information and direct key information on the crystal structure of Fe at the ultrahigh pressure–temperature conditions relevant for planetology. [ABSTRACT FROM AUTHOR]

This paper introduces a novel wafer-edge quality inspection method based on analysis of curved-edge diffractive fringe patterns, which occur when light is incident and diffracts around the wafer edge. The proposed method aims to identify various defect modes at the wafer edges, including particles, chipping, scratches, thin-film deposition, and hybrid defect cases. The diffraction patterns formed behind the wafer edge are influenced by various factors, including the edge geometry, topography, and the presence of defects. In this study, edge diffractive fringe patterns were obtained from two approaches: (1) a single photodiode collected curved-edge interferometric fringe patterns by scanning the wafer edge and (2) an imaging device coupled with an objective lens captured the fringe image. The first approach allowed the wafer apex characterization, while the second approach enabled simultaneous localization and characterization of wafer quality along two bevels and apex directions. The collected fringe patterns were analyzed by both statistical feature extraction and wavelet transform; corresponding features were also evaluated through logarithm approximation. In sum, both proposed wafer-edge inspection methods can effectively characterize various wafer-edge defect modes. Their potential lies in their applicability to online wafer metrology and inspection applications, thereby contributing to the advancement of wafer manufacturing processes. [ABSTRACT FROM AUTHOR]

Early childhood schoolbooks designed to teach children to read, have been shown not only to shape gendered identities in a limiting, binary format, but to lend the written word the appearance of unquestionable, and restrictive truth about the way the world is. Texts written for adults, too, may similarly limit what can be known, reining in the world's emergent efflorescence. Extending the concept of emergent listening, this paper develops the concept of emergent reading, a form of reading that is intimately and diffractively related to emergent listening and emergent writing. Emergent reading is relational, intra-acting with the emergent efflorescence of written words and with the materiality of the human and more-than-human world. [ABSTRACT FROM AUTHOR]

Acoustic applications of metamaterials have rapidly developed over the past few decades. The sound attenuation provided by metamaterials is due to the interaction between soundwaves and scatterers organized into a reticular grid, with a peak attenuation at a specific frequency band that is highly dependent on the scatterers' diameter and reticular geometric organization of installation. In this article, the scatterer types chosen for the experiments are represented by a 2D shape, which are cylindrical solid-wood bars of 15 mm diameter and empty cylindrical bars of 20 mm diameter. Acoustic measurements were conducted in a semi-anechoic chamber to identify the specific frequency at which the highest insertion loss (IL) was registered. A second experiment was conducted by creating holes of 5 mm diameter on the external surface of the empty bars; in this way, it registered a higher sound attenuation. In particular, the resonant system characterized with holes, in combination with the attenuation given by 2D scatterer metamaterials, increased the sound attenuation for the frequency range between 1 kHz and 10 kHz. [ABSTRACT FROM AUTHOR]

On the basis of diffraction transformations of wave fields, a mathematical model of a speckle interferometer of transverse displacements of a scattering object has been developed and numerical modeling of speckle-modulated interference patterns and signals at the output of the interferometer has been performed. Numerical calculations of the spatial distribution of complex amplitudes of wave fields in an interferometer were used for modeling when the displaced scattering surface was illuminated by two obliquely incident laser Gaussian beams. A statistical numerical experiment was performed to determine the measurement error of the scattering surface displacement caused by the change of realizations of interfering speckle fields. The simulation results are in good agreement with the results of experimental studies of transverse displacements in the range up to 600 micrometers. [ABSTRACT FROM AUTHOR]

The diffraction of plane surface and flexural-gravity waves during their normal incidence at the edge of a floating elastic semi-infinite plate in fluid of finite depth in the presence of a current with velocity shear is studied. The explicit analytical solution to this problem is constructed using the Wiener–Hopf technique. Simple exact formulas for the reflection and transmission coefficients and the energy relations are obtained. The results of numerical calculations using the obtained formulas are presented. [ABSTRACT FROM AUTHOR]

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Featured Application: This study belongs to the field of intelligent non-destructive testing and proposes a CNN-based method for accurate quantification of defect characterized by ultrasonic diffraction method. The innovation in this study lies in several key aspects: (1) Development of a CNN architecture that automatically classifies A-scan signals in the scan path; (2) Connectivity region solving algorithm to accurately calculate the defect-region size according to the classification results; (3) An intelligent noise reduction framework that enables accurate identification of defective areas in complex noise situations. The purpose of this paper is to automate the interpretation of data during ultrasonic diffraction using a non-destructive testing (NDT) technique to accurately size defects for assisting in decision-making. A convolutional neural network (CNN) architecture was developed to automatically measure the length of the defect. Using the architecture, the population of A-scan signals in the scanning path was classified. The defect region was extracted and its size in the scanning direction was obtained by the connected region solution algorithm based on the classification results. The arrival time of diffraction waves was accurately identified by the intelligent denoising framework proposed, combined with Hilbert transform, and then the height of defects was calculated by corresponding geometric relations. The estimation results demonstrate that the measurement method can be considered as a useful technique for crack sizing in industrial structures, even in the case of complex noise. [ABSTRACT FROM AUTHOR]

In this work, NiO and NiO–SiO2 are studied using X-ray diffraction and the method of atomic-pair radial distribution. Using X-ray phase analysis, it is determined that the sizes of NiO particles have a coherent-scattering region of more than 100 nm, while the NiO–SiO2 sample has particle sizes of about 2–3 nm. However, full-profile simulation using the Rietveld method does not allow one to describe the effects observed during diffraction: asymmetry of the peaks, the appearance of an additional shoulder of peak 111 in the region of small angles; therefore, the method of atomic-pair radial distribution is used to analyze the structure. When simulating the experimental curve of the atomic-pair radial distribution, 3 different models are used: pure NiO, a mixture of NiO and Ni2SiO4, as well as a modified NiO model with Si embedded into the crystal lattice. The latter model is created based on the assumption of the incorporation of silicon into the NiO structure, as can be evidenced by the X-ray diffraction data. According to the results of simulation of the curve of the atomic-pair radial distribution, it is the latter model that provides the best description of the observed effects: a significantly increased unit-cell parameter in comparison with the sample without the addition of SiO2, as well as decreased cation–oxygen distances in the structure while the distances between cations are increased. [ABSTRACT FROM AUTHOR]

While polarizer‐free (Pol‐less) OLED displays increase the efficiency of the panels with lowering the thickness, there comes an issue of the screen quality drop due to diffraction. We have investigated phenomena and invented a novel model for diffraction, since the color‐difference‐based evaluation alone has limitations in responding to customer needs in various environments and reflecting situations in which actual users embrace the screen quality. The main spatial features of the diffraction appearance were classified into the size and complexity of the pattern, and each factor was quantified through a specialized model. Diffraction features can be automatically calculated as numerical values from the invented model reflecting perceptual levels, which acts as a 'ruler' to achieve a good 'grade' of image quality in the product development stage. In this paper, we demonstrate what plays vital roles in diffraction appearance on Pol‐less displays and how to evaluate the diffraction in representative values. [ABSTRACT FROM AUTHOR]

This paper investigates diffraction issues in Under Display Infrared (UDIR) sensor applications for 3D facial recognition. While conventional design wisdom emphasizes infrared transmittance, this study introduces a new figure of merit, Zero‐Order Transmittance (ZOT) as a crucial parameter. Patterning the cathode significantly improves ZOT, highlighting its importance in UDIR applications. This emphasizes the need for careful consideration of pixel and aperture layout to achieve high ETZ without compromising performance such as resolution and lifetime of the display. [ABSTRACT FROM AUTHOR]

Reflective LCDs have a great advantage of low power consumption, but the brightness is not consistently sufficient because ambient light is used as a light source. To increase light efficiency, we combined reflective LCDs and the Pancharatnam‐Berry deflector (PBD), a diffractive optical element that controls the propagation of incident light. We confirmed that on‐axis brightness is increased by 2.2 times against the incident collimated light from a polar angle of 30° when compared to a reflective LCD without PBD. [ABSTRACT FROM AUTHOR]

Scanning transmission electron microscopy (STEM) is one of the most powerful characterization tools in materials science research. Due to instrumentation developments such as highly coherent electron sources, aberration correctors, and direct electron detectors, STEM experiments can examine the structure and properties of materials at length scales of functional devices and materials down to single atoms. STEM encompasses a wide array of flexible operating modes, including imaging, diffraction, spectroscopy, and 3D tomography experiments. This review outlines many common STEM experimental methods with a focus on quantitative data analysis and simulation methods, especially those enabled by open source software. The hope is to introduce both classic and new experimental methods to materials scientists and summarize recent progress in STEM characterization. The review also discusses the strengths and weaknesses of the various STEM methodologies and briefly considers promising future directions for quantitative STEM research.

This study employs an arts-based duoethnographic approach to contemplate the nuances of and understand the struggles that two researchers confronted in their new professional roles as art educators. The investigation focuses on how conversations, art practices, and reflective/diffractive analysis can help with understanding or processing professional identity development. The data include art practices, field notes, monthly meetings, and emails sent between February and May 2019. The main content of this article presents the two researchers’ exchange of emails and art pieces as part of the preliminary data analysis. Two pivotal elements stand out in the exploration: diffracting relationships and deconstructing perspectives that support growth and development during the process. Additionally, the investigation affirms that positive differences can be produced even though two researchers hold distinct perspectives. The methodology supports professional identity development as an ongoing and deconstructing process of searching for differences and being different.

This work reports the observation of sunlight diffraction through empty spaces in between twigs and leaves in tree crowns. The diffraction patterns are dominated by red wavelength on front followed by the trail of rest of spectral bands of white light rainbow bursts. Tree crowns act as obstacles and apertures causing diffraction/ interference of solar rays. Separation between leaves and twigs (d) is a few inches and distance between crown and camera (D) is in range of a few meters. Empty spaces in tree crown are much longer than red to violet wavelengths in sunlight therefore scattering, dispersion, reflection, diffraction and interference effects cannot be ruled out. Tree crown deflects solar rays into narrow angles all around to enable interference inside camera lens to create grating structure diffracting light into regular patterns. Diffraction pattern look like red petunia flower having 3 × 3 rose petals. Motorola mobile phone camera was used to record the sunlight diffraction patterns. Mobile camera consists of small focal length (≈5 mm) lens, a fixed opening aperture and an image sensor. Lens consists of few plastic or glass elements and sensor consists of charge coupled device (CCD) or CMOS technology. These diffraction/ interference patterns have potential to increase efficiency of Next Gen solar cells. This paper describes possible theoretical background of light diffraction and multiple ray interference through tree twigs and leaves.