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Exhibition spaces are where human civilization is passed along, science and culture are disseminated, and new design concepts and techniques are assimilated to better them over time. Several offline and online exhibitions have been affected, stopped, postponed, or relocated online due to the effect of the outbreak. Presently, the development and enhancement of virtual exhibition halls is underway. Visitors to exposition halls are no longer limited to those from the immediate area; rather, an increasing number of people come from all over the nation and even from other countries. Due to this, pavilions that are equipped with remote tour features become very influential. The cloud exhibition of the film and television art design elements is the focus of this study, and it additionally builds a virtual display platform and presents 3D Imaging and Virtual Reality Technology (3DIVRT). Through the lens of 3D modeling technology and virtual exhibition hall building, this study first investigates the application trend and preliminary practice of digital design in virtual exhibition halls domestically and internationally. A comparison is made between virtual exhibition halls and conventional exhibition halls to summarize the benefits and possibilities of virtual exhibition halls. Second, it elaborates on the features of the 3D experience found in virtual exhibition halls from immersion, interaction, and conceivability perspectives. A fundamental examination and comparison of 3D modeling software is carried out, and Blender and Unity’s impact on the execution of the virtual exhibition hall is detailed. Synchronizing virtual reflection by computational capabilities, which will be identified with certain examples from across the globe, requires multimedia to be successful. Various methods to exhibit activity that uses computer-aided technologies are brought to light in this research study. According to the findings and conclusions, manual presentation and technical distinctions are how artistic and reflective features can be achieved.

In order to provide a more immersive and interactive experience, a new VR rendering algorithm suitable for architectural design has been developed in this paper. In traditional methods, we have carefully analyzed the computer conversion process from 2D drawing to 3D modeling, and innovatively designed a graphics rendering algorithm aimed at accelerating and optimizing the rendering process. However, despite some progress, traditional technologies still face challenges such as limited interactivity and rendering quality bottlenecks. In view of this, the introduction of virtual reality technology was explored, and a lifelike 3D building environment was successfully constructed by seamlessly integrating real-time rendering engines, high-precision sensors, and advanced interactive devices. This environment not only achieves seamless connection and natural interaction between users and virtual building spaces, but also allows users to freely explore and observe building details in virtual roaming, and deeply interact with virtual elements, greatly enhancing immersive experience and interactive fun. The results indicate that in terms of design efficiency, virtual reality design time is generally shorter than traditional technologies. In terms of visual quality, virtual reality technology scores a perfect 5 points, while traditional technology only scores 4 points. In terms of rendering speed, virtual reality technology is 10s faster than traditional technology in residential scenes and 15s faster in commercial complex scenes. In terms of data processing capability, when processing 20 sets of data, the average processing speed of virtual reality technology is about 58s/GB, while traditional technology is 106s/GB. The average error rate of virtual reality technology is 1.0%, while traditional technology is 3.0%. In terms of user experience, the rating for virtual reality technology reached 9.2 out of 10, while traditional technology only scored 6.9. The immersion score for virtual reality technology is 9.3 points, while for traditional technology it is 6.7 points. The interactive depth rating for virtual reality technology is 8.7 points, while for traditional technology it is 6.0 points. In practical applications, the rendering time of virtual reality technology is significantly shorter than traditional rendering technology, and user satisfaction ratings are generally higher, with an average rating of 4.7 points or above (out of 5 points).

As the population of older adults increases worldwide, the number of individuals afflicted with cardiovascular issues and diseases is also increasing. The rate at which individuals worldwide succumb to cardiovascular disease (CVD) is rising as well. That is, the World Health Organization (WHO) reports that the number one cause of death globally is from CVD either in the form of myocardial infarctions or strokes. The primary ways of assisting individuals with CVD are from either improved treatments, monitoring research, or primary and secondary prevention measures. In the form of cardiovascular structural monitoring, ultrasonography is very prevalent and allows for multiple configurations, is the least expensive, and has no detrimental side effects to the patient.

This is the proof of concept study that investigates how we can combine a wearable ultrasound vest of multiple 2D transducers to create a 3D model of the heart for continuous monitoring. Furthermore, we create functional models to represent the states the heart can be in both respect to normal operations as well as Atrial Fibrillation.

Using the wearable ultrasound vest created in our previous work, a 3D model is created via a structure from motion approach with synthetic data. Also, a denoising process is created to assist the modeling process. The 3D model is constructed with up to three views. That is, via the parasternal, frontal, and apical views where the frontal view is the halfway point between the apical and parasternal views. Furthermore, stochastic petri nets (SPN) are created to represent the cyclic states of the heart.

The experimental results show a 3D model of the synthetic heart constructed from a point cloud created by the structure from the motion approach. Then, it is successfully denoised with our outlier detection and removal process. The resulting 3D model allows us to calculate surface areas and perform the continuous monitoring we initially set out to do. Finally, multiple SPN models are created for functional feature extraction as well as to assist medical professionals in continuous cardiovascular monitoring.

In this paper, we demonstrated the structure from the motion approach to create a 3D model of the heart with our wearable ultrasound vest construction. Furthermore, we provided multiple SPN models for functional feature extraction and to monitor a normal heart and a heart affected by Atrial Fibrillation.

Driven by key law enforcement and commercial applications, research on face recognition from video sources has intensified in recent years. The ensuing results have demonstrated that videos possess unique properties that allow both humans and automated systems to perform recognition accurately in difficult viewing conditions. However, significant research challenges remain as most video-based applications do not allow for controlled recordings. In this survey, we categorize the research in this area and present a broad and deep review of recently proposed methods for overcoming the difficulties encountered in unconstrained settings. We also draw connections between the ways in which humans and current algorithms recognize faces. An overview of the most popular and difficult publicly available face video databases is provided to complement these discussions. Finally, we cover key research challenges and opportunities that lie ahead for the field as a whole.

This paper defines a new three-dimensional (3D) Gaussian ray bundling model in geodetic coordinates: latitude, longitude, and altitude. Derivations are provided for 3D refraction, 3D interface reflection, 3D eigenray detection, and a 3D variant of the Comprehensive Acoustic System Simulation (CASS)/Gaussian Ray Bundling (GRAB) model. This approach allows environmental parameters and their derivatives are computed directly in latitude, longitude, and depth directions without reducing the problem to a series of $N\times \mathrm{\text{2D}}$ Cartesian projections. Our model supports 3D effects such as great circle routes and horizontal refraction in sloped environments. Key test results are included for ray path refraction accuracy using a Munk profile, Gaussian beam projection into the shadow zone for an $n^2$ linear profile, and horizontal refraction from a 3D analytic wedge. Testing to date indicates that this approach has accuracy at least as good as CASS/GRAB, but with improved execution speed benefits for large numbers of targets, and 3D transmission loss effects.

To generate a 3D computer model of a free-form object, multiple range images (point clouds) covering its entire surface are acquired from different viewpoints. These views are then aligned in a common coordinate basis by minimizing the distance error between their corresponding points. Establishing correspondences automatically is an inherently challenging problem due to the lack of any type of information other than the geometrical information extracted from the point clouds. Existing "automatic" correspondence techniques achieve automatism at the expense of other important specifications namely, applicability to free-form objects, accuracy, efficiency, robustness to resolution and surface sampling, robustness to overlap, robustness to noise and finally their applicability to simultaneous multiview correspondence. There is also a lack of a review paper that describes and critically analyzes these techniques. In this paper, we present such an extensive review and carry out the analysis of each technique according to the above listed indispensable criteria. Our analysis shows that none of these techniques fully meets these criteria and that there is still a need for the development of practical automatic correspondence algorithms.

Comprehensive spatial visualization of fiber tracts from all perspectives is a highly desirable outcome in brain studies. To achieve this aim, this study establishes the foundation for a new 3D visual interface that integrates Magnetic Resonance Imaging (MRI) to Diffusion Tensor Imaging (DTI). The need for such an interface is critical for understanding brain dynamics, and for providing accurate diagnosis of key brain dysfunctions, in terms of neuronal connectivity in the human brain. Two research fronts were explored: (1) the development of new image processing techniques resulting in comprehensive visualization mechanisms that accurately establish relational positioning of neuronal fiber tracts and key landmarks in semi-transparent 3D brain images, and (2) the design of key algorithms that do not tax the computational requirements of 3D rendering and feature extraction using 2D MRI and DTI frames, remaining within practical time constraints. The system was evaluated using data from thirty patients and volunteers with the Brain Institute at Miami Children's Hospital. The highly integrated and fully embedded fiber-tracking software system provides an optimal research environment for innovative visualization mechanisms of white matter fiber tracts. This 3D visualization system reached the implementation level that makes it ready for deployment at other clinical sites.

Changes of retinal blood vessel calibers may reflect various retinal diseases and even several non-retinal diseases. We propose a new method to estimate retinal vessel calibers from 3D optical coherence tomography angiography (OCTA) images based on 3D modeling using superellipsoids. Taking advantage of 3D visualization of the retinal tissue microstructures in vivo provided by OCTA, our method can detect retinal blood vessels precisely, estimate their calibers reliably, and show the relative flow speed visually.

The use of custom implants has recently gained increasing importance in craniofacial surgery in order to optimize preoperative planning and reduce operative time. The design of patient-specific implants plays an important role to restore craniofacial bone. Nevertheless, the design method has become the bottleneck. In this study, a new design method of a maxillofacial prosthesis based on the topology optimization was proposed to realize lightweight custom implants. At first, parametric predesign of the optimized model was carried out to ensure that the optimized model conformed to the main physiological anatomical structure and recover basic function structure. Then, the design region is defined under given load and boundary conditions. The material interpolation technique of SIMP with the penalization factor is adopted to get the final optimized 3D model. Finally, the experimental results verify that the method of topology optimization for the maxillofacial prosthesis proposed is efficient.

The study was to compare an off-loading cushion, designed for individuals with spinal cord injury, with air cushion to analyze the effect of pressure on skin injury and user satisfaction. The off-loading cushion can reduce the incidence of pressure ulcers by minimizing the pressure of the ischial tuberosity and coccyx. Because anatomical structures of each participant are different, 3D scanning is used in the customized manufacturing of the cushions. In the 3D modeling, the product is designed so that the ischial tuberosity and coccyx have minimal contact with the cushion’s surface area. The X-sensor was used to confirm the pressure dispersion effect. As a result, maximum pressure of the ischial tuberosity and the coccyx were measured and observed to be lower than that of the air cushion. User satisfaction was compared between two cushions using the QUEST 2.0. The off-loading cushion has slightly higher service and product satisfaction than the air cushion. Based on these findings, this study suggests that off-loading cushions reduce the occurrence of pressure injury compared to air cushions.

Total knee arthroplasty (TKA) has been the end-time surgical procedure for pain relief and movement restoration in cases of severe arthritis. The knee implant design plays a vital role in deciding the activity levels of a patient after total knee replacement (TKR). In about 90% of younger patients undergoing the knee replacement surgeries, the restriction is not from the subject but from the implant design. This paper discusses parameters affecting the activity levels after TKR. It also briefs the design aspects of a novel knee design that allows the normal high flexion activity even after TKR.

The application of finite element modeling in medical applications has been evolving as the field of high importance especially in the development of medical devices. The TKA has been in existence for over six decades till now. The generic artificial knee implants used in the TKA have the restriction in its range of motion of about 90°. A new design allowing flexion extension range of over 120° was designed with a view to facilitate partial squatting and the same is used for the analysis purpose. The loading conditions of 10 times the body weight are considered. The finite element analyses of the designs were carried out based on standard biomaterial used in orthopedic implants. In this paper, we have discussed the results of analyses of an artificial knee with titanium (Ti) alloy. The results of the analyses were used in identifying areas of extreme stresses within the design and the spot prone for higher deformation. Based on these results, slight modification on the designs was carried out. The results are also verified whether the body is within the linear deformation levels. As the results obtained were very satisfactory, the models have been recommended for prototyping.

Geometric models of human body organs are obtained from imaging techniques like computed tomography (CT) and magnetic resonance image (MRI) that oallow an accurate visualization of the inner body, thus providing relevant information about their its structure and pathologies. Next, these models are used to generate surface and volumetric meshes, which can be used further for visualization, measurement, biomechanical simulation, rapid prototyping and prosthesis design. However, going from geometric models to numerical models is not an easy task, being necessary to apply image-processing techniques to solve the complexity of human tissues and to get more simplified geometric models, thus reducing the complexity of the subsequent numerical analysis. In this work, an integrated and efficient methodology to obtain models of soft tissues like gray and white matter of brain and hard tissues like jaw and spine bones is proposed. The methodology is based on image-processing algorithms chosen according to some characteristics of the tissue: type, intensity profiles and boundaries quality. First, low-quality images are improved by using enhancement algorithms to reduce image noise and to increase structures contrast. Then, hybrid segmentation for tissue identification is applied through a multi-stage approach. Finally, the obtained models are resampled and exported in formats readable by computer aided design (CAD) tools. In CAD environments, this data is used to generate discrete models using finite element methed (FEM) or other numerical methods like the boundary element method (BEM). Results have shown that the proposed methodology is useful and versatile to obtain accurate geometric models that can be used in several clinical cases to obtain relevant quantitative and qualitative information.

Artistic anatomy involves the study of 3D forms which is related to the human body itself and its constitutive structures as the basis for 3D modeling of topographic line structures. Understanding artistic anatomy relies on visual and 3D spatial concepts and is the foundation of students’ education in developing games and making animations. By combining graphical data of anatomical structures with the production of digital sculptures, students were provided a new way to interact with anatomical structures. Six human sculpture sessions were planned for the course and tested both before and after the sessions. The results showed that the digital sculpture course resulted in a consistent improvement in students’ understanding and concepts of artistic anatomy and an understanding of the relationship between the line structure of the 3D model and the texture of the human body.

Modeling of 3D highway integrated with terrain model was firstly discussed in this paper, and a new method of judging the maximum angle was used to eliminate the distorted triangles on the boundary of model. It is a fundamental issue for visualization and analysis on 3D GIS at a rapid speed. To strip-distributed terrain data, this paper proposed a new dynamic multi-resolution model. Different from other models/algorithms, this algorithm need not pre-partition the model regularly and can achieve multi-resolution representation in one tile. In addition, such a condition was considered in the approach that only resolution level of parts of triangles will change in adjacent frames when roaming. That is, the resolution of parts of triangles which locate in the joints of adjacent resolution levels will change. Therefore, the speed of algorithm can be improved. Finally, a software prototype “VRHighWay”, developed by VC++ 6.0 and OpenGL, was introduced. The experimental results demonstrate that proposed method acquires better performance in terms of accuracy for the multi-resolution representation of terrains with roads embedded.

To render scenes by camera-based ambient intelligence, we propose a dense 3D modeling algorithm using feature points that dynamically appear and disappear over time; that is, we reconstruct a 3D model of the scene with a dense feature point set that "evolves" over time. As the scene's appearance changes due to camera movements, some existing feature points dynamically disappear while some new feature points dynamically appear relative to the camera. The newly generated feature points' 3D positions are initialized using nearby existing feature points' positions depending on their consistency including the distances in 2D image, stability and history. Our feature evolution, when incorporated into standard tracking and 3D reconstruction algorithms, provides more robust and denser 3D meshes. Consequently, the resulting 3D meshes and textures render novel 3D images better than meshes and textures produced using standard stereo techniques.