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This paper proposes an improved matching pursuit (MP) method with a multicomponent interference dictionary (MCID) based on a pipeline guided wave reflection model. The proposed method separates the overlapped time domain reflections from the notch edges and extracts parameters such as amplitude, time of flight (TOF), and phase to identify the number and axial dimensions of notches in pipes. Firstly, the performance of the method in identifying parameters of overlapped components affected by noise and reverberation under different signal-to-noise ratios (SNRs) and frequencies is analyzed using four error metrics. Secondly, finite-element (FE) models of pipes with a single notch and double notches are established, and the accuracy of the reflection model is validated by comparing the predicted amplitudes, TOF, and phase of reflections with the FE results. Finally, experimental validation is conducted on aluminum pipes with multiple notches. The consistency between the experimental results, theoretical results, and FE results in wave packet parameters confirmed the accuracy of the proposed reflection models. The method accurately captures the parameters of the reflections from each notch edge in the experimental pipes, enabling the identification of the number and axial dimensions of the notches. The method holds the potential for identifying a greater number of notches in pipelines and characterizing their axial dimensions. This can provide a reliable reference for developing maintenance plans based on pipeline operational conditions, thereby preventing major safety incidents. [ABSTRACT FROM AUTHOR]

The existing visible light communication simulation research on reflection is mainly based on the standard Lambertian model. In recent years, some papers have mentioned that the standard Lambertian model is too simplified and approximate to meet the actual situation. To solve this problem, a variety of more complex reflection models have been proposed. However, the more complex models require more computation. To balance computation and simulation accuracy, by consulting the literature, this study found that the standard Lambertian model has a certain requirement of the incident angle range to describe reflection on a wall covered in plaster. In this paper, the inappropriate index Q of the standard Lambertian model is defined, and then the relationship between Q and the light-emitting diode position with only the first reflection considered is determined through a preliminary calculation. The calculation shows that, in an empty room with plaster walls, and when the distance is greater than 0.685 m, the standard Lambertian model can be used; when the distance is less than 0.685 m, other, more complex models need to be adopted according to the actual situation. [ABSTRACT FROM AUTHOR]

We consider a Couette flow of a rarefied Ar gas with heat transfer between two wall surfaces and investigate the scattering behavior of gas molecules reflected either at a clean Pt surface or at a surface contaminated with adsorbates. Water molecules abundantly present in the atmosphere were adopted as the adsorbates. The reflection of gas molecules on the lower wall surface was simulated by Molecular Dynamics (MD) method to obtain accommodation coefficients and velocity distribution functions of gas molecules. We applied the modified reflection model of gas molecule and investigated the velocity distribution functions of the model by comparing the MD results to verify the validity. The accommodation coefficients obtained by the MD method depend on the number of adsorbed water molecules on the lower wall surface. Specifically, tangential momentum accommodation coefficient (TMAC) tended to increase and then decrease with the increase in adsorbed water molecules, but normal momentum accommodation coefficient (NMAC) tended to decrease monotonically. The velocity distribution functions of the modified reflection model approximately show the good agreement with the MD calculation but the degree of coincidence depends on the speed difference between the upper and lower wall surfaces, and the number of adsorbed water molecules on the surface.

Serious games are transcending the way of teaching and learning nowadays. Since serious games balance playful and educational aspects, it constitutes a privileged learning method for the digital natives. However, they are ubiquitous in today's society and their stakes and assets remain largely fuzzy. This paper describes different models and frameworks for serious games design. Between theoretical and technical consideration, authors propose a new reflection model that aims to help pedagogues guiding their conception of serious games. This model is a result of a thematic synthesis analyzing more than 40 texts offering a three-layered model covering the simplest to the most advanced design. Three study cases are announced to be conducted by the end of this year in order to challenge and evaluate this new model. [ABSTRACT FROM AUTHOR]

The Bidirectional Reflectance Distribution Function (BRDF) of beryllium is important for a ray-tracing simulation to evaluate the effect of reflected light on optical diagnostics in the fusion device ITER. However, the BRDF for beryllium has not been investigated yet and is currently lacking. To fill this gap, this study measured BRDFs of beryllium specimens with different topographies using goniophotometers and optimized optical reflection models. Additionally, various surface topographic parameters were computed, and their correlation with parameters for the optical reflection models was explored. As a result, it was found that topographic parameters related to slope offer a certain correlation with the parameters of the reflection model. This can be useful for determining the optical reflection properties of materials for which direct BRDF measurements are not possible. • The Bidirectional Reflectance Distribution Functions (BRDFs) of beryllium are shown. • Topographic parameters have a certain correlation with a reflection model. • The maximum coefficient of determination for the correlation exceeds 0.91. • Improving the optical reflection model is the key to better correlations. [ABSTRACT FROM AUTHOR]

In order to verify the feasibility of using microwave to study Yellow River ice, the reflected power of pure ice and mixed ice is measured by electromagnetic waves of different polarisations and frequencies in the microwave chamber. The measured data of microwave chamber measurement was processed to obtain radar cross section values. Based on the experiments in the microwave chamber, this study presents a reflection model for calculating the reflection of pure ice. The calculated value obtained by the model is consistent with the measured values, which also proves the validity of the model. The results of this study will provide some basis for the follow-up study of retrieval Yellow River ice thickness.

In order to verify the feasibility of using microwave to study Yellow River ice, the reflected power of pure ice and mixed ice is measured by electromagnetic waves of different polarisations and frequencies in the microwave chamber. The measured data of microwave chamber measurement was processed to obtain radar cross section values. Based on the experiments in the microwave chamber, this study presents a reflection model for calculating the reflection of pure ice. The calculated value obtained by the model is consistent with the measured values, which also proves the validity of the model. The results of this study will provide some basis for the follow-up study of retrieval Yellow River ice thickness. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Image & Graphics is the property of Editorial Office of Journal of Image & Graphics 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.)

In this paper, we propose a model to characterize Infrared (IR) signal reflections on any kind of surface material, together with a simplified procedure to compute the model parameters. The model works within the framework of Local Positioning Systems (LPS) based on IR signals (IR-LPS) to evaluate the behavior of transmitted signal Multipaths (MP), which are the main cause of error in IR-LPS, and makes several contributions to mitigation methods. Current methods are based on physics, optics, geometry and empirical methods, but these do not meet our requirements because of the need to apply several different restrictions and employ complex tools. We propose a simplified model based on only two reflection components, together with a method for determining the model parameters based on 12 empirical measurements that are easily performed in the real environment where the IR-LPS is being applied. Our experimental results show that the model provides a comprehensive solution to the real behavior of IR MP, yielding small errors when comparing real and modeled data (the mean error ranges from 1% to 4% depending on the environment surface materials). Other state-of-the-art methods yielded mean errors ranging from 15% to 40% in test measurements. [ABSTRACT FROM AUTHOR]

This paper presents a CFD (Computation Fluid Dynamic) simulation and experimental results for the reflected radiation error from turbine vanes when measuring turbine blade’s temperature using a pyrometer. In the paper, an accurate reflection model based on discrete irregular surfaces is established. Double contour integral method is used to calculate view factor between the irregular surfaces. Calculated reflected radiation error was found to change with relative position between blades and vanes as temperature distribution of vanes and blades was simulated using CFD. Simulation results indicated that when the vanes suction surface temperature ranged from 860 K to 1060 K and the blades pressure surface average temperature is 805 K, pyrometer measurement error can reach up to 6.35%. Experimental results show that the maximum pyrometer absolute error of three different targets on the blade decreases from 6.52%, 4.15% and 1.35% to 0.89%, 0.82% and 0.69% respectively after error correction. [ABSTRACT FROM AUTHOR]

Reflective and reflexive practice has become an integral component of practitioner professional training, particularly within professions associated with psychology and nursing. One way of facilitating reflective and reflexive practice is to integrate sensitivity of social interrelated constructs and social differences in relation to Gender, Race, Religion, Age, Abilities, Class, Culture, Ethnicity, Education, Sexual orientation and Spirituality as outlined in the GRRAACCEESS acronym. Inspired from the eighteen-century sailing vessel replica ‘La Grace’,this paper extends Burnham’s original GRRAACCEESS acronym by adding ‘Language’ and ‘Anatomy’ to form the ‘LA GRRAACCEESS’ model. This paper explores the merits and implications of the LA GRRAACCEESS model in order to assist practitioners with unravelling or deconstructing reflective practice and encourage ongoing mindful reflective practice. [ABSTRACT FROM PUBLISHER]

In this article, the influence of texture surface of a fabric on its instrumental color is investigated. While former studies have found it is difficult to establish a quantitative relationships between texture of fabric and its instrumental color (color difference and color attributes, such as lightness, chroma, and hue), this article investigates from a theoretical and empirical perspective the interaction between texture and color. Eighty four knitted cotton yarn dyed fabric samples in four color centers and 21 texture structures were used in this study. It is revealed that fabric samples with different texture surfaces define a set of lines with identical direction in the reflectance space, and thus the normalized reflectance curves of these samples are identical. In the CIEXYZ space, tristimulus values of these fabric samples define a line, and thus their chromaticity coordinates are constant. In the CIELAB space, however, linearity is lost due to the non-linear transformation from the CIEXYZ space to the CIELAB space. The finding of this article has the potential to discount the influence of texture of a fabric on its color. Experiments show that the influence of texture on color for samples in the four color centers can be reduced by 79, 55, 71, and 57%, respectively comparing to the real measured color difference. © 2014 Wiley Periodicals, Inc. Col Res Appl, 40, 472-482, 2015 [ABSTRACT FROM AUTHOR]

For a gas turbine blade working in a narrow space, the accuracy of blade temperature measurements is greatly impacted by environmental irradiation. A reflection model is established by using discrete irregular surfaces to calculate the angle factor between the blade surface and the hot adjacent parts. The model is based on the rotational angles and positions of the blades, and can correct for measurement error caused by background radiation when the blade is located at different rotational positions. This method reduces the impact of reflected radiation on the basis of the turbine's known geometry and the physical properties of the material. The experimental results show that when the blade temperature is 911.2 5 K and the vane temperature ranges from 1011.3 to 1065.8 K, the error decreases from 4.21 to 0.75%. [ABSTRACT FROM AUTHOR]

Introduction: One of the most important characteristic of human being is his ability to learn. Structuralists believe that learning is an active process through which learners explores the principles, meanings and facts by themselves. Learner's participation in learning process is one of the active learning strategies and reflective learning is considered as an active teaching method which is in direct relationship with learner's attempts to advance professional capabilities and competencies. The aim of this study is to determine and present related topics to the subject of reflection in learning for students and teachers. Methods: This review study was performed through searching scientific databases such as Wiley, Elsevier, Pubmed, and Google scholar as well as using search engines such as Google to retrieve results. The key words were learning, reflective, reflective learning, reflective teaching, and reflection. A total of 90 Persian and English published evidences such as articles, books and web pages during 2009-2013 were retrieved and finally 26 evidences related to subject were selected. Results: After the review of selected articles and texts on reflective teaching and learning, issues such as reflection, reflection models, reflection and Kolb learning cycle, reflective learning, advantages of reflective learning and methods for its promotion, and reflective teaching were discussed. Conclusion: Since reflection is considered as an effective method in learning, it seems necessary to continue employing this method for all learners and teachers in all levels. [ABSTRACT FROM AUTHOR]

The practice of written reflections as a source for creating awareness, evaluating and decision making for classroom instructional and managerial decisions is synonymous with student teachers, especially during the practicum. However, there is the reality of these written entries being denigrated to detached descriptive pieces of journal entries, especially if the practicum stretches over a period of time. How then does the student teacher move beyond the level of personal recounts and achieve a higher level of awareness of self-efficacy? This paper proposes the reflection model which considers three elements: reflective writing, reflective dialoguing and self-efficacy to be necessary for critical reflection. As a preliminary report, the paper concentrates on one element – reflective dialoguing. Excerpts from the sessions show that when provided with opportunities to critically evaluate and talk about these reflections with their peers and lecturers on a regular basis, the student teachers are able to sharpen and target their observations to build local funds of knowledge bases, e.g. on the students, the school, the community, and at the same time to critically reflect on their own beliefs and practices, which in turn helped inform them of their own pedagogic choices and practices in the classroom. [ABSTRACT FROM PUBLISHER]

Rendering a polygonal surface with Phong normal interpolation allows shading to appear as it would for a true curved surface while maintaining the efficiency and simplicity of coarse polygonal geometry. However, this approximation fails in certain situations, especially for grazing viewing directions. Well-known problems include physically impossible reflections and implausible illumination. Some of these artifacts can be mitigated through special-case processing, although no universal or generally accepted approaches are available. In particular, all known solutions that guarantee that reflected rays will always point outward from the surface also create discontinuities in the reflection ray direction. We present a simple modification of Phong normal interpolation that allows physically plausible reflections and creates an appearance of a smooth surface. We introduce an additional scalar parameter that characterizes the deviation between per-vertex normals and per face normals and use it to adjust linearly interpolated normals. The proposed technique eliminates perceptually objectionable artifacts caused by inconsistencies between the shading and geometric normals while retaining most of the practical advantages and simplicity of the original Phong formulation. [ABSTRACT FROM AUTHOR]

A method for determining the three-dimensional shape and surface reflectance of an object from images is presented. The method is based on a combination of Moiré analysis and a reflection model, and is defined for objects with reflectance formulated using Phong's reflection model. Objects are regarded as consisting of multiple surfaces, each with specific and uniform reflectance, and the number of regions is assumed to be known for simplicity. The proposed method overcomes two problems in reflectance estimation: ambiguity of reflectance due to the relationship between the surface normal and the components of diffuse and specular reflectance, and the lack of reflectance information for pixels with zero intensity due to the grating pattern employed for Moiré analysis. Using multiple light sources, multiple images with shifted grating phase are captured and analyzed for Moiré analysis. The method is confirmed through numerical simulations and experiments to obtain accurate shape and reflectance information, with a significant improvement over existing image-based methods. © 2006 Wiley Periodicals, Inc. Syst Comp Jpn, 37(6): 32–43, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20442 [ABSTRACT FROM AUTHOR]

Translucent objects are characterized by diffuse light scattering beneath the object's surface. Light enters and leaves an object at possibly distinct surface locations. This paper presents the first method to acquire this transport behavior for arbitrary inhomogeneous objects. Individual surface points are illuminated in our DISCO measurement facility and the object's impulse response is recorded with a high-dynamic range video camera. The acquired data is resampled into a hierarchical model of the object's light scattering properties. Missing values are consistently interpolated resulting in measurement-based, complete and accurate representations of real translucent objects which can be rendered with various algorithms. [ABSTRACT FROM AUTHOR]

A method is described for estimating the refractive index of the material of an object surface with convex shape in natural scenes. The refractive index is an optical constant that is inherent to the surface material. This optical parameter is not only useful for identifying the material of an object surface, but also important for creating realistic images of the object. It is difficult to measure the refractive index of any material in natural scenes, except for transparent materials. In this paper, we consider estimation of the refractive index for relatively smooth surfaces of inhomogeneous dielectric materials by using a calibrated CCD camera. First, we show how the appearance of an image including specular highlights changes with the refractive index. This parameter is then estimated from the camera data of specular highlights of an object surface at different directions of illumination and viewing. The estimation algorithm is based on histogram analysis using the Torrance–Sparrow reflection model. The estimated refractive index is compared with direct measurements using a refractometer. Moreover the feasibility of the proposed method is demonstrated in computer graphics images created by using the estimated reflection parameters. [Copyright &y& Elsevier]

Health professionals are required to reflect on practice to evaluate and improve care in rapidly changing health care environments. This study explored the professional development needs of educators facilitating development of reflective capacity in midwifery students using the Bass Model of Holistic Reflection. Thirteen midwifery academics at two Australian universities took part in the study conducted in three phases. Phase 1 identified the learning needs of educators described as 'understanding the building blocks of reflection' ; ' practical application of the model, and 'assessment of reflective capacity'. Phase 2 involved an Intervention including development of a reflective practice tool kit and delivery of a two-day workshop. Phase 3 evaluated the experience of educators using the resources and four themes emerged: 1) ' Educators value a reflective practice toolkit '; 2) ' A toolkit builds confidence and trust in the model through promotion of deep personal reflection' ; 3) ' Effective use of the model is key to achieving consistency in application by educators ; and 4) ' Deeper understanding of the model promotes transformation of practice '. This paper confirms the importance of developing resources for educators, that support reflective pedagogy when implementing models of reflection into curricula. • Reflective skill development requires effective facilitation and role modelling. • The Bass Model provides educators with a resource to scaffold reflective capacity. • The toolkit supports consistency of application of the Bass Model by educators. • Embedding reflective pedagogy in curricula builds reflective capacity. • Educators require a tool capable of measuring the holistic continuum of reflection. [ABSTRACT FROM AUTHOR]