3D Media Research Articles

Longitudinal quasi-electrostatic waves in hyperbolic metasurfaces

Inspired by the recent optical investigations on the hyperbolic metasurfaces, we study the possibility of new quasi-electrostatic waves propagation in such anisotropic 2D materials that do not propagate in the case of a regular 2D medium. The analytical result shows that the dispersion relation of these waves is free from the effects of permittivities of the surrounding media. These new waves may be considered as longitudinal quasi-electrostatic waves.

VISUAL 3D PLANOGRAM MEMPERMUDAH PEMASANGAN MATERIAL PROMOSI HANDPHONE

Smartphone retail sales in Indonesia are currently growing very rapidly. Point of Sales Material (POSM) is used to provide information about products to consumers, using displays to stimulate impulsive buying behavior. This study designed a 3D planogram visual media, which can visualize real-time with text, images, and videos. Media that has been developed by researchers is in the very good category with a percentage of 78% for the promoter segment that is more than 1 year and 77% for the new promoter segment who has worked at Samsung retail for less than 1 year. From the results of experalidation and user validation, for the aspect of video visualization and the 3D planogram module that has been developed, the category average AB score is 81-85. The display arrangement process can be done more quickly and precisely because the understanding of the planogram increases.

Eigenrays in 3D heterogeneous anisotropic media, Part II: Dynamics

ABSTRACTThis paper is the second in a sequel of two papers and dedicated to the computation of paraxial rays and dynamic characteristics along the stationary rays obtained in the first paper. We start by formulating the linear, second‐order, Jacobi dynamic ray tracing equation. We then apply a similar finite‐element solver, as used for the kinematic ray tracing, to compute the dynamic characteristics between the source and any point along the ray. The dynamic characteristics in our study include the relative geometric spreading and the phase correction due to caustics (i.e. the amplitude and the phase of the asymptotic form of the Green's function for waves propagating in 3D heterogeneous general anisotropic elastic media). The basic solution of the Jacobi equation is a shift vector of a paraxial ray in the plane normal to the ray direction at each point along the central ray. A general paraxial ray is defined by a linear combination of up to four basic vector solutions, each corresponds to specific initial conditions related to the ray coordinates at the source. We define the four basic solutions with two pairs of initial condition sets: point–source and plane‐wave. For the proposed point–source ray coordinates and initial conditions, we derive the ray Jacobian and relate it to the relative geometric spreading for general anisotropy. Finally, we introduce a new dynamic parameter, similar to the endpoint complexity factor, presented in the first paper, used to define the measure of complexity of the propagated wave/ray phenomena. The new weighted propagation complexity accounts for the normalized relative geometric spreading not only at the receiver point, but along the whole stationary ray path. We propose a criterion based on this parameter as a qualifying factor associated with the given ray solution. To demonstrate the implementation of the proposed method, we use several isotropic and anisotropic benchmark models. For all the examples, we first compute the stationary ray paths, and then compute the geometric spreading and analyse these trajectories for possible caustics. Our primary aim is to emphasize the advantages, transparency and simplicity of the proposed approach.

Eigenrays in 3D heterogeneous anisotropic media, Part I: Kinematics

ABSTRACTWe present a new ray bending approach, referred to as the Eigenray method, for solving two‐point boundary‐value kinematic and dynamic ray tracing problems in 3D smooth heterogeneous general anisotropic elastic media. The proposed Eigenray method is aimed to provide reliable stationary ray path solutions and their dynamic characteristics, in cases where conventional initial‐value ray shooting methods, followed by numerical convergence techniques, become challenging. The kinematic ray bending solution corresponds to the vanishing first traveltime variation, leading to a stationary path between two fixed endpoints (Fermat's principle), and is governed by the nonlinear second‐order Euler–Lagrange equation. The solution is based on a finite‐element approach, applying the weak formulation that reduces the Euler–Lagrange second‐order ordinary differential equation to the first‐order weighted‐residual nonlinear algebraic equation set. For the kinematic finite‐element problem, the degrees of freedom are discretized nodal locations and directions along the ray trajectory, where the values between the nodes are accurately and naturally defined with the Hermite polynomial interpolation. The target function to be minimized includes two essential penalty (constraint) terms, related to the distribution of the nodes along the path and to the normalization of the ray direction. We distinguish between two target functions triggered by the two possible types of stationary rays: a minimum traveltime and a saddle‐point solution (due to caustics). The minimization process involves the computation of the global (all‐node) traveltime gradient vector and the traveltime Hessian matrix. The traveltime Hessian is used for the minimization process, analysing the type of the stationary ray, and for computing the geometric spreading of the entire resolved stationary ray path. The latter, however, is not a replacement for the dynamic ray tracing solution, since it does not deliver the geometric spreading for intermediate points along the ray, nor the analysis of caustics. Finally, we demonstrate the efficiency and accuracy of the proposed method along three canonical examples.

Suppression of transport anisotropy at the Anderson localization transition in three-dimensional anisotropic media

We study the transport of classical waves through three-dimensional (3D) anisotropic media close to the Anderson localization transition. Time-, frequency-, and position-resolved ultrasonic measurements are performed on anisotropic slab-shaped mesoglass samples to probe the dynamics and the anisotropy of the multiple scattering halo, and hence to investigate the influence of disorder on the nature of wave transport and its anisotropy. These experiments allow us to address conflicting theoretical predictions that have been made about whether or not the transport anisotropy is affected by the interference effects that lead to Anderson localization. We find that the transport anisotropy is significantly reduced as the mobility edge is approached---a behavior similar to the one predicted recently for matter waves in infinite anisotropic 3D media.

Hanoman's 2D animated character in ramayana wayang story

Research in art creation is an effort to preserve traditional arts, especially wayang kulit in the form of character development of the Hanoman character in the Ramayana story through animated 2D media which aims to introduce traditional skills among the younger generation in Surakarta. This research method of art creation uses a qualitative descriptive approach through data sources, including Ramayana puppet shows, literature studies, and competent speakers in the field of puppetry and animation. The stages of analysis from various sources of results from information from both literature reviews and interviews were carried out using an interactive model, where each component of the research includes the stages of data collection, data reduction, presentation and conclusion drawing. Test the validity of the data using data triangulation techniques, namely triangulation of data sources and triangulation of theories. The locations of designing 2D animated Hanoman characters go through several processes, namely: the Envisioning Phase, the Planning Phase, the Design/Design Stage, the Stabilizing Phase, and the Deploying Phase. The Hanoman character in the Ramayana wayang story collaborates with 2D animation technology as an alternative to introducing wayang characters and educational media that are suitable for the younger generation segmentation.

What happens in porous media during oil-phase emulsification?

Shell scientists are making the most of advancing imaging technology to reveal what happens in a 3D porous medium during emulsification.

PERANCANGAN MOTION COMIC 2D PERAN DAN FUNGSI MAMAK DALAM SISTEM KEKERABATAN MINANGKABAU

The contribution and function of information and communication media as information disseminators include studying and preserving the civilization of social and cultural values in the Minangkabau community both in print media, 2D audio visual and 3D media. As today, modern society or the millennial generation does not really care about the role and function of the Mamak towards their nephews, and millennial youth tend to see the values of tracing traditions as ancient, while the influence of outside culture is very vulnerable to be diminished, including in Minangkabau. So there is a need for information and communication media to disseminate education to Minangkabau adolescents such as 2D motion comics which present moving picture stories to discuss the role and function of Mamak in looking after their nephews. As the target audience, Minangkabau youth are expected to be interested in understanding the values of Minangkabau cultural civilization through this motion comic. This design method uses the 4D development model, namely define, design, develop, and disseminate. While the data analysis method uses a SWOT analysis, namely Strengths, Weaknesses, Opportunities, and Threats. The main media in this design work is the Motion comic, which consists of illustrations of moving cutouts where the final result is using Youtube Channel to play Motion comic videos online. Furthermore, it is supported by other media in the form of T-shirts, posters, comics, pins, note books, stickers, x-banners.Keyword: Motion Comic, Mamak, Minangkabau,

THE EFFECT OF DISCOVERY LEARNING BASED 3D SCRAPBOOK MEDIA TOWARD MOTIVATION AND LEARNING OUTCOMES

Discovery learning learning model is an effective model for advancing student motivation and learning outcomes. The aim of this research is to understand the effect of discovery learning model based on 3D scrapbook media on building material on student motivation and learning outcomes of fifth grade students at SDN Munungkerep II Kabuh. This type of research uses a quantitative approach, the research design that is used is the post-test only control design. The population in this study was fifth grade students of SDN Munungkerep Kabuh Jombang with saturated sampling techniques. The data analysis techniques that are used are validity test, normality test, and multivariate variant test (MANOVA). The results showed that (1) The application of discovery learning model based on 3D scrapbook media on space building material influenced the motivation of class students based on a significant value of 0.193 ≥ 0.05, (2) The application of discovery learning model based on 3D scrapbook media on space building material affect the learning outcomes of class students based on a significant value of 0.246 ≥ 0.05, and (3) The application of discovery learning models using 3D scrapbook media on building materials has an effect on motivation and student learning outcomes based on a significant value of 0.433 ≥ 0.05.

Make Full Use of Priors

Multi-view video plus depth (MVD) is the promising and widely adopted data representation for future 3D visual applications and interactive media. However, compression distortions on depth videos impede the development of such applications, and filters are crucially needed for the quality enhancement at the terminal side. Cross-view priors can intuitively be involved in filter design, but these priors are also distorted in compression and thus the contribution of them can hardly be considered in previous research. In this article, we propose a cross-view optimized filter for depth map quality enhancement by making full use of inner- and cross-view priors. We dedicate to evaluate the contributions of distorted cross-view priors in filtering the current view of depth, and then both inner- and cross-view priors can be involved in the filter design. Thus, distortions of cross-view priors are not barriers again as before. For the purpose of that, mutual information guided cross-view consistency is designed to evaluate the contributions of cross-view priors from compression distortions of MVD. After that, under the framework of global optimization, both inner- and cross-view priors are modeled and taken to minimize the designed energy function where both data accuracy and spatial smoothness are modeled. The experimental results show that the proposed model outperforms state-of-the-art methods, where 3.289 dB and 0.0407 average gains on peak signal-to-noise ratio and structural similarity metrics can be obtained, respectively. For the subjective evaluations, object details and structure information are recovered in the compressed depth video. We also verify our method via several practical applications, including virtual view synthesis for smooth interaction and point cloud for 3D modeling for accuracy evaluation. In these verifications, the ringing and malposition artifacts on object contours are properly handled for interactive video, and discontinuous object surfaces are restored for 3D modeling. All of these results suggest that compression distortions in MVD can be properly filtered by the proposed model, which provides a promising solution for future bandwidth constrained 3D and interactive visual applications.

Investigating the neural activity of various 3D visual fatigue degrees using depth‐related visual evoked potentials

AbstractSevere visual fatigue symptoms occur while users view three‐dimensional (3D) content. These symptoms adversely affect the user experience and hinder the widespread application of 3D media. Existing studies mainly used electroencephalography (EEG) power (based on frequency domain analysis) to evaluate 3D visual fatigue (3DVF), but their results were often contradictory and confusing. To address this problem, we investigated the relationship between EEG features and visual fatigue from the perspective of both time and time‐frequency domain. Random‐dot stereograms (RDS) with various disparities were employed to elicit depth‐related visual evoked potentials (VEPs). The experiment lasted about 27 min for each subject to induce fatigue, and the EEG was recorded synchronously. VEPs of different fatigue levels were processed to extract both time (such as P120 and N170 components in VEPs) and time‐frequency (like event‐related spectral perturbation [ERSP]) domain characteristics. A significant increase in P120 amplitude was observed in the parietal region, and time‐frequency analysis also revealed a significant ERSP decrease of theta bands in the central‐frontal region with a latency of 200 to 300 ms when subjects suffered fatigue. Our results confirm the hypothesis that activity of theta decreased with 3DVF level, or rather, we found ERSPs of theta bands on FC4 and Cz in the 200‐ to 300‐ms window decreased significantly across four fatigue levels. Furthermore, we first reported the relationship between P120 amplitude and 3DVF, which implied this feature could be considered as a feature of 3DVF evaluation. In summary, our studies could provide a new insight for 3DVF evaluation using EEG.

Soundtrack loudness as a depth cue in stereoscopic 3D media

Assisted by the technological advances of the past decades, stereoscopic 3D cues are being integrated increasingly in both interactive and non-interactive media. Arguably, the main focus of this effort is placed on the creation of an increased sense of visual depth. Considering that human perception relies heavily on the audiovisual integration rather than on visual information alone, it is rather surprising that relatively little attention has been given so far to the potential effect of the soundtrack on 3D depth perception in contrast to the evident interest towards the study of realistic 3D audio spatialisation techniques and technologies. The multisensory nature of human perception suggests that the potential of sound design as a means to influence depth perception in the stereoscopic 3D visual environments may be worthy of further exploration. This study reports on our research into the possibilities of using alterations of the volume levels of the soundtrack in order to influence the perception of visual depth while viewing stereoscopic 3D animation clips. Based on previous findings indicating that the volume level of the soundtrack may be related to the perception of visual depth, a series of experiments further explored the effectiveness of this auditory cue. Results suggest that, under certain conditions, differences in volume levels of the soundtrack could influence the judgement of visual depth in a way that frequently contradicts real-life expectations. It is suggested that different, more metaphorical perceptual mechanisms may be in play when viewing stereoscopic 3D presentations than in real life. In this context, we conclude that stereoscopic 3D media can benefit from further exploration of the effectiveness of certain auditory cues as a means to influence the perception of depth within the stereoscopic 3D environment.

Role of cellulose family in fibril organization of collagen for forming 3D cancer spheroids: In vitro and in silico approach.

Introduction: Cell aggregation of three-dimensional (3D) culture systems (the so-called spheroids) are designed as in vitro platform to represent more accurately the in vivo environment for drug discovery by using semi-solid media. The uniform multicellular tumor spheroids can be generated based on the interaction of cells with extracellular matrix (ECM) macromolecules such as collagen and integrin. This study aimed to investigate the possible interactions between the cellulose family and collagen using both in vitro and in silico approaches. Methods: The 3D microtissue of JIMT-1 cells was generated using hanging drop method to study the effects of charge and viscosity of the medium containing cellulose family. To determine the mode of interaction between cellulose derivatives (CDs) and collagen-integrin, docking analysis and molecular simulation were further performed using open source web servers and chemical simulations (GROMACS), respectively. Results: The results confirmed that the addition of CDs into the 3D medium can promote the formation of solid spheroids, where methylcellulose (MC) yielded uniform spheroids compared to carboxymethyl cellulose (CMC). Moreover, the computational analysis showed that MC interacted with both integrin and collagen, while sodium carboxymethyl cellulose (NaCMC) only interacted with collagen residues. The stated different behaviors in the 3D culture formation and collagen interaction were found in the physicochemical properties of CDs. Conclusion: Based on in vitro and in silico findings, MC is suggested as an important ECM-mimicking entity that can support the semi-solid medium and promote the formation of the uniform spheroid in the 3D culture.

Virtual anthropology: a preliminary test of macroscopic observation versus 3D surface scans and computed tomography (CT) scans

Virtual anthropology (VA) is based on applying anthropological methods currently used to analyse bones to 3D models of human remains. While great advances have been made in this endeavour in the past decade, several interrogations concerning how reliable these models are and what their proper use should be remain unanswered. In this research, a fundamental assumption of VA has been investigated: if the way we perceive and apply an anthropological method is truly similar when looking at bones macroscopically and through various 3D media. In order to answer, 10 skulls of known age and sex were scanned using a computed tomography (CT) scanner and a 3D surface scanner. Two observers separately applied a defined staging method to eight suture sites on these skulls, first looking at the bone macroscopically, then at the 3D surface scan, and finally on the CT scan. Two rounds of observation were carried out by each observer. Intra- and inter-observer error were evaluated, and two sample t-tests used to evaluate if the different types of medium used yielded significantly different observations. The results show a high degree of inter-observer error, and that data obtained from 3D surface scans differ from macroscopic observation (confidence level 95%, P ≤ 0.05). CT scans, in these settings, yielded results comparable to those obtained through macroscopic observations. These results offer many possibilities for future research, including indications on the kind of anthropological methods and anatomical landmarks that might be reliably transferable to the virtual environment. All current methods used in traditional anthropology should be tested, and if they prove unreliable, new techniques to analyse bones from virtual models should be developed. Key points Large discrepancies between observation on dry bones and computer-generated 3D models (surface scans or CT scans) could lead to the re-evaluation of the suitability of traditional anthropological methods for application on 3D models. This preliminary study evaluates whether macroscopic, 3D surface scans, and CT scans viewings generate different observations. The results indicate that the data are not always coherent across all three media of observation. Explanations include the aspect given to the bone by the 3D software, differences between handling bones in real life versus on a computer, and level of expertise of the observers.

Non-reciprocal Rayleigh wave propagation in space–time modulated surface

Research on non-reciprocal propagation of waves is of great significance in the field of photonic and phononic crystals for realizing flexible one-way propagation devices with potential engineering applications. Here, non-reciprocal Rayleigh waves are investigated in a continuous two-dimensional (2D) semi-infinite medium bound with an array of space–time modulated spring–mass oscillators. The involved modulation is a wave-like perturbation of the surface of the continuous medium that breaks time-reversal symmetry and reciprocity. To characterize the propagation of Rayleigh waves in such a complex 2D medium with continuous and discrete interface, an analytical study is performed to obtain dispersion-engineered bandgaps by adopting the asymptotic method and coupled mode theory, which is also validated by numerical simulation. Specifically, the non-reciprocal transmission of Rayleigh waves with one-way mode conversion is illustrated, and various relevant physical quantities, including conversion length and band gap size, are quantitatively estimated. This work sheds light on versatile control of Rayleigh wave propagation ranging from sensing and evaluation of engineering structures to guided wave-based damage detection techniques.

The role of the spatial heterogeneity and correlation length of surface wettability on two-phase flow in a CO2-water-rock system

This study characterized and modeled heterogeneous surface wettability in sandstone and investigated the role of spatial heterogeneity and correlation length of surface wettability on relative permeability in a supercritical CO2 (scCO2)-brine-rock system. Understanding the role of wettability heterogeneity on relative permeability is essential to geological CO2 sequestration, oil and gas recovery, and contaminated groundwater remediation. Although numerous studies have attempted to understand the influences of surface wettability, capillary number (Ca), and viscosity ratio, the role of the spatial variation and correlation length of surface wettability on two-phase flow in three-dimensional (3D) porous media has not been unraveled due to the challenges in the measurement and representation of realistic rock surface wettability. In this work, we conducted in-situ measurements of surface contact angle (CA) in a Bentheimer sandstone after CO2 flooding using micro-computed tomography (micro-CT), and found that the pore-scale CA distribution on rock surfaces followed a log-normal distribution associated with a spatial correlation length. Based on the statistical information from CT scanning, a Gaussian random field was used to model CA distributions that had desired standard deviations and spatial correlation lengths, which were then adjusted within a certain range of values for sensitivity analyses to study their combined effects on the two-phase flow in the porous medium using the lattice Boltzmann (LB) method. The LB two-phase flow simulation was accelerated using hybrid, multicore parallel computing to overcome the challenges in simulating multiphase flow in a large 3D domain having 800 × 800 × 600 nodes. The simulation results showed that the surface wettability heterogeneity (i.e., standard deviation of CA) had a lesser effect on the relative permeability of the wetting fluid (water) but a more significant impact on the relative permeability of the non-wetting fluid (scCO2). The Corey model was used to fit the LB-simulated relative permeability curves of water and scCO2 and showed that the variations in the relative permeability curves for both water and scCO2 increased as the standard deviation and spatial correlation length of CA increased. This study illustrated that the assumption of homogeneous surface wettability may cause errors in multiphase flow simulations. The impacts of both the standard deviation and spatial correlation length of CAs should be accounted for. This is the first study that explored the spatial correlation lengths associated with CA distributions on sandstone surfaces and comprehensively investigated the roles of both spatial variation and correlation length of CA on two-phase flow properties in 3D porous media. The optimized LB multiphase flow model was proved a powerful tool to study the interplays and combined effects of these statistical parameters, which had critical applications in numerous natural and engineering processes that involved multiphase flow in porous media.

Extended finite volume method with enriched HPCK shape functions for dynamic crack propagation modeling

In the present work, an extended finite volume method (EFVM) is incorporated with the enriched hp-cloud approximate function which has Kronecker delta property (EHPCK) for modeling crack propagation in 2D media. In this approximation function, appropriate crack path enrichment and crack tip enrichment functions are considered for modeling the discontinuous displacement field of cracked bodies. Unlike the conventional FVM approach, in the proposed EFVM, excessive control volumes (CVs) are embedded inside the main CVs which are called here as enrichment control volumes (ECVs). The EFVM method doesn't restrict the crack propagation path to obey any predefined path or edges of control volumes. To increase the prediction accuracies, the subtriangular technique is applied for the integration on the cracked control volumes. Capability of introduced EFVM is investigated by solving different problems such as dynamic stress intensity factor calculations and dynamic crack propagation.

Slice-to-voxel stochastic reconstructions on porous media with hybrid deep generative model

Three-dimensional (3D) microstructures are useful for studying the spatial structures and physical properties of porous media. A number of stochastic reconstructions are essential to discover the geometry and topology of the porous media and the its flow behavior. While several deep-learning based generative models have been proposed to deal with the issue, the obstacles about stable training and difficulty in convergence limit the application of these models. To address these problems, a hybrid deep generative model for 3D porous media reconstruction is proposed. The hybrid model is composed of a variant autoencoder (VAE) and a generative adversarial network (GAN). It receives a two-dimensional image as input and generates 3D porous media. The encoder from VAE characterizes the statistical and morphological information of input image and generates a low-dimensional feature vector for generator. Benefiting from the hybrid model, the training becomes more stable and the generative capability is enhanced as well. Furthermore, a simple but useful loss function is used to help improve accuracy. The proposed model is tested on both isotropic and anisotropic porous media. The results show the synthetic realizations have good agreement to the targets on visual inspection, statistical functions and two-phase flow simulation.

Quantifying scattering from dense media using two-dimensional impedance maps.

A better understanding of ultrasound scattering in a three-dimensional (3D) medium can provide more accurate methods for ultrasound tissue characterization. The possibility of using two-dimensional impedance maps (2DZMs) based on correlation coefficients has shown promise in the case of isotropic and sparse medium [Luchies and Oelze, J. Acoust. Soc. Am. 139, 1557-1564 (2016)]. The present study investigates the use of 2DZMs in order to quantify 3D scatterer properties of dense media from two-dimensional (2D) histological slices. Two 2DZM approaches were studied: one based on the correlation coefficient and the other based on the 2D Fourier transform of 2DZMs. Both 2DZM approaches consist in estimating the backscatter coefficient (BSC) from several 2DZMs, and then the resulting BSC was fit to the theoretical polydisperse structure factor model to yield 3D scatterer properties. Simulation studies were performed to evaluate the ability of both 2DZM approaches to quantify scattering of a 3D medium containing randomly distributed polydisperse spheres or monodisperse ellipsoids. Experimental studies were also performed using the histology photomicrographs obtained from HT29 cell pellet phantoms. Results demonstrate that the 2DZM Fourier transform-based approach was more suitable than the correlation coefficient-based approach for estimating scatterer properties when using a small number of 2DZMs.

A unifying theory for two-dimensional spatial redistribution kernels with applications in population spread modelling.

When building models to explain the dispersal patterns of organisms, ecologists often use an isotropic redistribution kernel to represent the distribution of movement distances based on phenomenological observations or biological considerations of the underlying physical movement mechanism. The Gaussian, two-dimensional (2D) Laplace and Bessel kernels are common choices for 2D space. All three are special (or limiting) cases of a kernel family, the Whittle-Matérn-Yasuda (WMY), first derived by Yasuda from an assumption of 2D Fickian diffusion with gamma-distributed settling times. We provide a novel derivation of this kernel family, using the simpler assumption of constant settling hazard, by means of a non-Fickian 2D diffusion equation representing movements through heterogeneous 2D media having a fractal structure. Our derivation reveals connections among a number of established redistribution kernels, unifying them under a single, flexible modelling framework. We demonstrate improvements in predictive performance in an established model for the spread of the mountain pine beetle upon replacing the Gaussian kernel by the Whittle-Matérn-Yasuda, and report similar results for a novel approximation, the product-Whittle-Matérn-Yasuda, that substantially speeds computations in applications to large datasets.