Reflective Medium Research Articles

An alternative approach for detecting cavities in reinforced concrete structures using GPR A-scan data

This paper introduces an alternative approach for detecting cavities in reinforced concrete walls using Ground Penetrating Radar (GPR) A-scan data. GPR, leveraging electromagnetic waves, is extensively applied for cavity detection within structures. The nature of electromagnetic waves, significantly influenced by reflective media and attenuating through them, requires specialized analysis methods for data interpretation. Traditional methods often involve identifying and eliminating overlapping reflection patterns or adjusting signal magnitude at specific depths to isolate peak signals from the target object's surface, which can be subjective and complex. To overcome these challenges, this study proposes quantitatively assessing the presence of cavities by analyzing the integral area of A-scan data within suspected ranges. Observations indicate a substantial difference in reflection patterns between areas with and without cavities, showcasing the potential of this approach for quantitative cavity detection. This approach offers a more objective and quantitative basis for identifying cavities in reinforced concrete structures.

Imaging Analysis of Scratch Reduction in Poly (Methyl Methacrylate) (PMMA) Plastic with NOVUS Polishing Products

ABSTRACT Remediation of disfiguring scratches and abrasions on aging plastics challenges even the most experienced conservator. This study assesses the effect of three NOVUS polishing products on remediation of poly (methyl methacrylate) (PMMA). Samples were prepared to mimic the depth and type of scratches observed during conservation treatment performed on vacuum-formed reliefs from the 1960s. The study compares samples of new/unaged PMMA to naturally aged PMMA samples. Two different methods were successfully used to assess the polishing efficacy, which is notoriously challenging to document in transparent and reflective media: (1) image segmentation analysis of photographs to yield scratched area fractions, using three approaches (Li-thresholding, random forest, and convolution neural network); and (2) optical profilometry measurements, which provide surface root-mean-square roughness (RRMS) values. Both methods support the qualitative observations that polishing with the abrasive NOVUS products significantly reduced the surface damage; scratch area fractions decreased from 50–60% to 1–5% across the aged PMMA types after treatment, corresponding to an ∼85% decrease in surface roughness. Critically, the two methods are complementary: the image segmentation results demonstrated a greater visible difference between two degrees of polishing treatments on the new material, while profilometry results were able to parse differences in the degree of scratch reduction between the aged and new materials.

2D Shear Wave Imaging in Gaussian Noise and Reflection Media

Shear wave imaging (SWI) is a rapid and convenient method of collecting images of tissues in the region of interest. SWI is based on the mechanical properties of soft tissues named the complex shear modulus (CSM). The complex shear modulus consisting of the elasticity and the viscosity, is useful for diagnosing pathological tissue conditions. Previous studies have not fully exploited the estimation of CSM in the medium containing Gaussian noise and the shear wave's reflection phenomenon. In this study, we focused on the model of shear wave propagation in the 2D environment by the time domain finite difference method (FDTD), taking into account the effect of Gaussian noise and reflected shear wave. We then reduced the noise of the measured particle velocity using a designed least mean square filter. Finally, for direct estimation of CSM, Helmholtz algebraic inverse transformation algorithm was used. Reflected waves significantly affect the estimation of CSM, especially the tissue's viscosity, which is demonstrated by numerical simulation results.

Web Exclusive. Annals Graphic Medicine - More Than Suturing Wounds.

Web Exclusives7 January 2020Annals Graphic Medicine - More Than Suturing WoundsFREEAnnie Zhu, BHSc and Arnav Agarwal, MDAnnie Zhu, BHScSearch for more papers by this author and Arnav Agarwal, MDSearch for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/G19-0063 SectionsAboutVisual AbstractPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail Download figure Download PowerPoint Comments0 CommentsSign In to Submit A Comment Author, Article, and Disclosure InformationAffiliations: Disclosures: Authors have disclosed no conflicts of interest. Forms can be viewed at www.acponline.org/authors/icmje/ConflictOfInterestForms.do?msNum=G19-0063.Author/Illustrator Information: Annie Zhu is a medical student at the University of Toronto. She is interested in sequential art and exploring narratives in medicine. Her other illustrations and comics can be found at cazezhu.carbonmade.com. Dr. Arnav Agarwal is an internal medicine resident at the University of Toronto. He is passionate about clinical epidemiology research, health advocacy and allyship, and medical curriculum development and has a deep appreciation for art and narrative writing as media for reflection and advocacy. PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetails Metrics 7 January 2020Volume 172, Issue 1Page: W28KeywordsClinical epidemiologyConflicts of interestDisclosureHealth care ePublished: 7 January 2020 Issue Published: 7 January 2020 Copyright & PermissionsCopyright © 2020 by American College of Physicians. All Rights Reserved.PDF downloadLoading ...

The Study on Degradation and Separation of RhB Under UV Light by Magnetically ZnO/Fe2O3 Nanoparticles

Different percentages of Fe2O3 are composited with ZnO via a chemical precipitation method which is shown to be more efficient and convenient than other methods. The obtained products are analyzed by using X‐ray diffraction (XRD), transmission electron microscopy (TEM), X‐ray photoelectron spectroscopy (XPS), UV–vis diffuse reflection spectra (DRS), photoluminescence (PL), and vibrating sample magnetometer (VSM). Rhodamine B (RhB) dye is used as a simulated pollutant to cause degradation under UV light. Degradation efficiency is used to evaluate the photocatalytic activity of the composite catalysts. Compared with other samples, the results indicate that 7 wt.% ZnO/Fe2O3 composite shows the highest photocatalytic activity for RhB dye. Furthermore, the particles reduce secondary pollution and prolong the service life of the photocatalyst. The addition of a magnetic carrier allows the composite catalyst to be better separated from the reflection media.

Media for reflection: A comparison of renaissance mirrors for princes and contemporary management education

This article develops the concept media for reflection in the interest of conceptualizing the interpretative frames that enable and limit reflection in management and leadership education. The concept ‘media for reflection’ allows us to conceptualize the social and cultural mediation of reflection without reducing reflection to an effect of the social structures and cultural norms in which it is embedded. Based on the developed theoretical framework, this article analyses how a renaissance ‘mirror for princes’ and contemporary research-based management education mediate reflection. The content of the mediations is analysed as well as the societal and organizational background. Furthermore, the means by which the two media enable and limit reflection in different ways is compared. Finally, the article discusses possible implications of the analysis in terms of management and leadership education.

스토리텔링을 적용한 중학교 수학 수업에 대한 교사의 인식 및 활용 실태

본 연구의 목적은 스토리텔링을 적용한 2009개정 교과서로 직접 수업을 진행한 중학교 담당교사들을 대상으로 스토리텔링에 대한 인식을 조사하고, 수업의 활용 실태를 분석하여 스토리텔링의 효과적인 현장 적용을 위한 기초 자료를 제공하고자 하는 것이다. 이를 위해 스토리텔링 교과서에 대한 중학교 교사들의 인식과 스토리텔링 수업의 활용 실태를 알아보는 설문지를 구성하였고, 경기도 김포시와 일산, 부천 지역에 근무하는 중학교 1,2학년 담당교사 48명을 대상으로 설문 및 면담을 통한 조사 연구를 실시하였다. 연구결과, 교사들은 스토리텔링 교과서의 다양한 소재와 활동에 따른 창의력과 사고력 증진에 대해 긍정적인 반응을 보였으나 스토리텔링에 대한 깊이 있는 이해가 부족하였고, 교과서의 내용과 구성의 부자연스러움을 지적하였다. 또한 여러 가지 형태의 스토리텔링 자료들이 활용되고 있었는데, 특히 동적인 자료가 수업에 많이 활용됨을 알 수 있었다. 교사들은 단원의 도입부분에 스토리텔링을 가장 많이 활용하고 있으며, 교사와 학생간의 문답활동을 통하여 수학 개념이 전달되는 형태로 스토리텔링 수업이 많이 진행되는 것으로 나타났다. The big issue of mathematics education in 2009 revised curriculum is to introduce story-telling in math textbook and to aim toward the math that students can learn easily and interestingly. Therefore, this study examine the perception of middle school teachers in working with story-telling, analyze actual utilization of story-telling in class and provide the basic materials for effective practical application. After making questionnaires to check the real conditions of the story-telling and asking math teachers in charge of the first and second graders, this research came to the conclusion as follows. First, the teachers who took part in this research showed positive perception in story-telling textbook the practical use of a variety of materials and the improvement of thinking faculty and creativity. Second, math teachers made use of a variety of storytelling data and especially reflection media in class, but this was limited in introductory part. Mathematic concept was delivered mainly through the activities of exchanging questions and answers between the teachers and students. Third, students showed positive reaction about story-telling class on the whole. For example, they understood the concept easily and they could apply it in real life. However, story-telling failed to bring the attention and interest of math itself. Therefore, teachers' ability is needed in the way that math knowledge and concept should be formed and expressed interestingly.

Tracing the reflective practices of student teachers in online modes

AbstractDuring the course of pre- and in-service teacher education programmes, reflection can happen in a number of ways, for example: reflective journals, personal stories and pair/group co-operative discussions, professional development portfolios, and blogs and electronic portfolios. The aim of this paper is to examine various technologies such as online chat, discussion forums and blogs, in terms of their suitability and affordances as reflective media. It begins by examining positional survey data gathered from student teachers (STs) who have used these social media over a period of time. Following this it focuses on one of the desired outcomes of Reflective Practice (RP), the construction of teacher identity as part of the process of becoming a professional. The construction of identity through the mediational tool of language used across these modes is examined through a corpus linguistics lens. Collections of language produced around RP activities are analysed as a corpus in quantitative and qualitative ways. These complementary sources of data in a mixed-methods approach provide some insights into the technologies and their potential in a Language Teacher Education (LTE) context. To this end, our findings suggest that blogs, in particular, foster narration, RP and the expression of identities, while chat and forums promote emotional and affective engagement, all of which can be useful to STs at the initial and continuing stages of their career.

Forensic Memory, Responsibility, and Judgment

Among the political documentaries produced in Chile in the postauthoritarian era there is a significant corpus of films that carry out a meticulous process of forensic memory. Both documentaries that dig through skeletal remains and those that excavate the memories of surviving victims or witnesses of state terror are carrying out similar archaeological forensic work. They examine records that, rather than simply evidencing past violence, exhibit the fractures (subjective and discursive) from which the past may be reconstructed. By focusing on these tasks the films La ciudad de los fotógrafos (Sebastián Moreno, 2007), El juez y el general (Elizabeth Farnsworth and Patricio Lanfranco, 2008), and El diario de Agustín (Ignacio Agüero, 2008) become media for reflection that makes it possible for viewers to confront their own history—in order to make ethical judgments that allow them to assume personal and collective responsibility in the face of a history that they have lived or have assimilated through a process of “post-memory.” To the question posed by Arendt—whether thinking can help to correct and eradicate acts of radical evil—we could respond that postauthoritarian Chilean documentary finds itself dealing precisely with this possibility through accounts that, by means of personal experience and sifting through one’s own biographical ruins, call on spectators to delve into their own fears and complicities. Dentro de los innumerables documentales políticos producidos en Chile en el período postautoritario, hay un corpus significativo que ha llevado a cabo un cuidadoso trabajo memorial-forense. Tanto aquellos documentales que hurgan en las reliquias óseas como los que escarban en las memorias de víctimas sobrevivientes o testigos del terror de Estado llevan a cabo un trabajo arqueológico forense. Escrutan registros en que, más que dar cuenta de la violencia de los hechos mismos, exhiben la fractura (subjetiva-discursiva) desde donde se reconstruye dicho pasado. Para tal contexto, los filmes La ciudad de los fotógrafos (Sebastián Moreno, 2007), El juez y el general (Elizabeth Farnsworth y Patricio Lanfranco, 2008), y El diario de Agustín (Ignacio Agüero, 2008) se constituyen en espacios de reflexión para hacer posible que el espectador encare su propia historia, elabore un juicio ético que le permita asumir una responsabilidad personal y colectiva frente a una historia que ha vivido biográficamente o que ha asimilado a través de la transmisión postgeneracional, vía un proceso de “post-memoria.” A la interrogante planteada por Arendt—¿puede el ejercicio de pensar ayudar a corregir y erradicar los actos de maldad radical?—podríamos responder que el cine documental chileno postautoritario se encuentra precisamente abordando esta posibilidad a través de relatos que, mediante experiencias personales y atravesando las propias ruinas biográficas, interpelan al espectador para adentrarse en sus propios lastres, miedos y complicidades.

Printing spatially-varying reflectance for reproducing HDR images

We present a solution for viewing high dynamic range (HDR) images with spatially-varying distributions of glossy materials printed on reflective media. Our method exploits appearance variations of the glossy materials in the angular domain to display the input HDR image at different exposures. As viewers change the print orientation or lighting directions, the print gradually varies its appearance to display the image content from the darkest to the brightest levels. Our solution is based on a commercially available printing system and is fully automatic. Given the input HDR image and the BRDFs of a set of available inks, our method computes the optimal exposures of the HDR image for all viewing conditions and the optimal ink combinations for all pixels by minimizing the difference of their appearances under all viewing conditions. We demonstrate the effectiveness of our method with print samples generated from different inputs and visualized under different viewing and lighting conditions.

Printing spatially-varying reflectance for reproducing HDR images

We present a solution for viewing high dynamic range (HDR) images with spatially-varying distributions of glossy materials printed on reflective media. Our method exploits appearance variations of the glossy materials in the angular domain to display the input HDR image at different exposures. As viewers change the print orientation or lighting directions, the print gradually varies its appearance to display the image content from the darkest to the brightest levels. Our solution is based on a commercially available printing system and is fully automatic. Given the input HDR image and the BRDFs of a set of available inks, our method computes the optimal exposures of the HDR image for all viewing conditions and the optimal ink combinations for all pixels by minimizing the difference of their appearances under all viewing conditions. We demonstrate the effectiveness of our method with print samples generated from different inputs and visualized under different viewing and lighting conditions.

Rethinking Digital Cultures and Divides: The Case for Reflective Media

Research exploring the means by which new media technologies can shape development within marginalized communities worldwide has began to move away from discussion limited to technical and infrastructural, to consider the interactions, beliefs, and values of local communities. Yet most projects continue to focus on enabling communities to access external information, rather than on the possibility of using media to catalyze community reflection and thereby developmental activity from within. This article shows how this promise can be actualized by providing an overview of an experimental project that made available a set of video cameras to a carefully selected group of community members in a ritualized, largely nonliterate village in Andhra Pradesh, India. It concludes that policymakers, researchers, and practitioners would benefit from considering the possibilities that reflective media hold to generate collective action and consensus building, and that these possibilities can synergize with the need to develop scalable projects.

Nós também temos voz: dinâmicas e movimentos em análise

This article is based on fi eldwork carried out during research conducted in a public school in Lisbon. Cinema is used as a medium for refl ection on violenc...

Lifelong learning and second‐order learning objects

AbstractCurrent cultural, social, and economic trends challenge traditional concepts of learning and lifelong learning. This paper draws on the twofold nature of learning in a knowledge society and explores options for technological support. The concept of Second‐Order Learning Objects is introduced as a potential means to foster generative learning. Generative learning goes beyond that what is already known and extends or transforms the socially shared knowledge including its artefacts and practices. According to the notion of individual and social learning as a process of reflective action, the role of strategies and media for reflection and inquiry is stressed. This paper outlines the use of schematically represented strategies for learning and reflection and sketches important features of a pursuant modelling approach.

Novel technique for the design of ultra-fast, high-resolution, broad-spectrum, wide-angle catadioptric lenses

A new optical design technique for catadioptric imaging optics is described, that permits near-zero values for the classical Seidel aberrations at relative apertures faster than f/1, with field angles over 3 deg arc, ~ 106 resolved pixels, a 600-nm bandwidth in the visible and near infrared and zero vignetting. Performance is limited only by high-order aberrations. The principle is that of combining the concentricities of a spherical concentric catoptric and a spherical concentric catadioptric, by optical superposition of the centers of curvature. The only full-aperture component is a spherical mirror; all other surfaces are spherical, except for an optional small weak zonal corrector. The new design approach is suited to aperture diameters of ~ 100 mm to > 1m when used with appropriate electronic detectors. Variants are possible for any segment of the electromagnetic spectrum for which there are suitable refractive and reflective media. In general, a large improvement in data acquisition rate is possible compared to that of existing designs.

Communication. Finding a reflective media for radio

Communication. Finding a reflective media for radio