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A three-dimensional (3D) cursor for autostereoscopic 3D displays was proposed. The cursor is based on voxel patterns. In the experiments, the cursor position is interactively controlled in 3D by a computer mouse with a scroll wheel. A computer program operates in the image plane of the 3D display directly without complicated geometric calculations. The results were verified in a 3D display with a parallax barrier and can be applied to other types of autostereoscopic displays. [ABSTRACT FROM AUTHOR]

Surgical software is a computer program that helps surgeons to optimize surgical procedures before they enter the operation room. The surgical planning software lets surgeons manipulate a 3D com- puter model of the patients body. Through this, the exactness, de- pendability and safety of the surgery can be improved diverting the preoperative planning into real surgical guide. However, it is quite difficult to design and manufacture the surgical guide without proper clinical applications. This study lays the foundation of the importance of various clinical applications and 3D manufacturing technologies to help surgeons design and manufacture surgical templates with high accuracy and high efficiency to save more lives in lesser time. [ABSTRACT FROM AUTHOR]

This article reports on a method to digitally survey and build virtual patterns for removable partial denture (RPD) frameworks using a new three-dimensional (3D) computer-aided design/computer-assisted manufacturing (CAD/CAM) software package developed specifically for RPD design. The procedure included obtaining 3D data from partially dentate casts, deciding on the path of insertion, and modeling the shape of the components of the frameworks digitally. The completed model data were stored as stereolithography (STL) files, which are commonly used in transferring CAD/CAM models to rapid prototyping technologies. Finally, metal RPD frameworks were fabricated using a selective laser melting technique. [ABSTRACT FROM AUTHOR]

Study Design: Prospective trial.Objective: To establish an individualized navigation template for safe and accurate insertion of lower cervical anterior transpedicular screw (ATPS) based on a three-dimensional (3D) printing technique.Summary Of Background Data: Conventional screw insertion manually under fluoroscopy easily leading to deviation of ATPS screw channel, cervical instrumentation procedures demand the need for a precise technique for screw placement.Methods: Twenty adult cervical spine specimens (10 men and 10 women, with a mean age of 50.29 ± 6.98) were selected for computed tomography pre- and postoperatively. A 3D lower cervical spine model was reconstructed using Mimics software to measure the screw-related parameters and generate a reverse template with optimal screw channel as well as a prototype using 3D printing. Assisted by the navigation template, bilateral ATPS were inserted into the cadavers.Results: The mean outer width and height of pedicle were 5.31 ± 1.23 and 6.78 ± 1.10 mm, respectively. The average length, sagittal, and axial angles of the optimal screw channel obtained through the optimal entry point were 36.34 ± 4.39 mm, 40.67° ± 5.10°, and 93.7° ± 7.96°, respectively. The adjustable safe ranges of sagittal and axial angles were 3.89° ± 1.13° and 5.64° ± 0.97°, respectively. The axial and sagittal accuracies of the 200 screws were 99.5% and 97%, respectively. The average deviations of the actual entry point and the preset opening in the X, Y, and Z axes were 0.39 ± 0.43, 0.21 ± 0.41, and 0.29 ± 0.14 mm, respectively (P > 0.05).Conclusion: An individualized ATPS navigation template was developed using Mimics software and 3D printing prototyping, based on computed tomography, for highly accurate screw insertion.Level Of Evidence: 4. [ABSTRACT FROM AUTHOR]

Like the parallel computers of the 1980s and 1990s, today’s 3D-chip technology will require new theory in software and algorithms to fully exploit. [ABSTRACT FROM AUTHOR]

With the ongoing introduction of wide-FOV VR head-worn displays into the consumer market, the application of VR 3D UIs to professional work environments is attracting increasing attention. One of the most conspicuous concepts is immersive 3D modeling and content creation. In spite of the long research history and multitude of proposed systems, there have been very few analyses of the effect of 3D UIs on productivity in 3D design. In this work, we explore the effect of positional head-tracking and its accompanying parallax depth cues on task performance in 3D object selection and transformation in a setting modeled after 3D design work. Previous studies have come to different conclusions on the importance of positional head-tracking and did not investigate professional 3D modeling tools. In contrast, we performed a user study with design students using professional software on a task that closely emulates their work. Surprisingly, we did not find a significant effect of positional head-tracking on task-completion time, neither when using a traditional 2D mouse nor when using a pinch glove as a 3D input device. Furthermore, we found that the users worked significantly faster with the mouse. We discuss possible explanations and implications for the design of 3D UIs. [ABSTRACT FROM AUTHOR]

During the creative process, designers use various techniques and strategies to move from the abstract to the concrete, utilizing different physical and virtual means to represent form. The changes between virtual and physical models are not always fluent, however. Differential 3D scanning can detect the differences between a scanned model (point cloud) and a reference model (polygon mesh or CAD model) and then reflect those changes in the reference model. This can save designers time by reconstructing only the small changed regions rather than the entire object. [ABSTRACT FROM PUBLISHER]

In order to achieve autonomous operation, the kinematics model and experiment system of telescopic excavator are studied. Firstly, the operation space of the robotic excavator is classified and mapping models between different spaces are established based on the D-H method and geometrical relationship method. Then, the virtual prototype of the telescopic robotic excavator is built based on the SimMechanics software, leveling operation and digging operation are simulated; kinematics model and virtual prototype are tested and verified. Finally, experimental system is developed and trajectory tracking experiment is carried out. By comparing with the simulation results, the validity of the proposed control scheme is verified. The research of this article laid foundations for further study and application. [ABSTRACT FROM AUTHOR]

Applications of video in fisheries research range from simple biodiversity surveys to three-dimensional (3D) measurement of complex swimming, schooling, feeding, and territorial behaviors. However, researchers lack a transparently developed, easy-to-use, general purpose tool for 3D video measurement and event logging. Thus, we developed a new measurement system, with freely available, user-friendly software, easily obtained hardware, and flexible underlying mathematical methods capable of high precision and accuracy. The software, VidSync, allows users to efficiently record, organize, and navigate complex 2D or 3D measurements of fish and their physical habitats. Laboratory tests showed submillimetre accuracy in length measurements of 50.8 mm targets at close range, with increasing errors (mostly <1%) at longer range and for longer targets. A field test on juvenile Chinook salmon ( Oncorhynchus tshawytscha) feeding behavior in Alaska streams found that individuals within aggregations avoided the immediate proximity of their competitors, out to a distance of 1.0 to 2.9 body lengths. This system makes 3D video measurement a practical tool for laboratory and field studies of aquatic or terrestrial animal behavior and ecology. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to develop a novel capsulorhexis system. Setting: Mechatronics Laboratory, University of Erciyes and Kayseri Maya Eye Hospital. Design: A 3D model was created and simulations were conducted to develop a new device which was designed, fabricated and tested for continuous curvilinear capsulorhexis (CCC). The name of this system is the electro-mechanical capsulorhexis system (EMCS). Methods: The 3D model was created by using a commercial design software and a 3D printer was used to fabricate the EMCS Finite element analysis and geometrical relation tests of the EMCS for different sized lenses were performed. Results: The results show that the EMCS is a perfect solution for capsulorhexis surgeries, without mechanical or geometrical problems. Conclusions: The EMCS can open the anterior lens capsule more easily and effectively than manual CCC applications and needs less experience. [ABSTRACT FROM AUTHOR]

This paper describes the development of auto-stereoscopic three-dimensional (3D) display with an eye-tracking system for not only the X-axis (right-left) and Y-axis (up-down) plane directions but also the Z-axis (forward-backward) direction. In the past, the eye-tracking 3D system for the XY-axes plane directions that we had developed had a narrow 3D viewing space in the Z-axis direction because of occurrence of 3D crosstalk variation on screen. The 3D crosstalk variation on screen was occurred when the viewer's eye position moved back and forth along the Z-axis direction. The reason was that the liquid crystal (LC) barrier pitch was fixed and the LC barrier was able to control the only barrier aperture position. To solve this problem, we developed the LC barrier that is able to control the barrier pitch as well as the barrier aperture position in real time, corresponding to the viewer's eye position. As a result, the 3D viewing space has achieved to expand up to 320-1016 mm from the display surface in the Z-axis direction and within a range of ±267 mm in the X-axis direction. In terms of the Y-axis direction, the viewing space is not necessary to be considered, because of a stripe-shaped parallax barrier. [ABSTRACT FROM AUTHOR]

To be used as input in most simulation and modelling software, 3D city models should be geometrically and topologically valid, and semantically rich. We investigate in this paper what is the quality of currently available CityGML datasets, i.e. we validate the geometry/topology of the 3D primitives (Solid and MultiSurface), and we validate whether the semantics of the boundary surfaces of buildings is correct or not. We have analysed all the CityGML datasets we could find, both from portals of cities and on different websites, plus a few that were made available to us. We have thus validated 40M surfaces in 16M 3D primitives and 3.6M buildings found in 37 CityGML datasets originating from 9 countries, and produced by several companies with diverse software and acquisition techniques. The results indicate that CityGML datasets without errors are rare, and those that are nearly valid are mostly simple LOD1 models. We report on the most common errors we have found, and analyse them. One main observation is that many of these errors could be automatically fixed or prevented with simple modifications to the modelling software. Our principal aim is to highlight the most common errors so that these are not repeated in the future. We hope that our paper and the open-source software we have developed will help raise awareness for data quality among data providers and 3D GIS software producers. [ABSTRACT FROM AUTHOR]

The MRC binary file format is widely used in the three-dimensional electron microscopy field for storing image and volume data. Files contain a header which describes the kind of data held, together with other important metadata. In response to advances in electron microscopy techniques, a number of variants to the file format have emerged which contain useful additional data, but which limit interoperability between different software packages. Following extensive discussions, the authors, who represent leading software packages in the field, propose a set of extensions to the MRC format standard designed to accommodate these variants, while restoring interoperability. The MRC format is equivalent to the map format used in the CCP4 suite for macromolecular crystallography, and the proposal also maintains interoperability with crystallography software. This Technical Note describes the proposed extensions, and serves as a reference for the standard. [ABSTRACT FROM AUTHOR]

In addition to precise 3D coordinates, most light detection and ranging (LIDAR) systems also record "intensity", loosely defined as the strength of the backscattered echo for each measured point. To date, LIDAR intensity data have proven beneficial in a wide range of applications because they are related to surface parameters, such as reflectance. While numerous procedures have been introduced in the scientific literature, and even commercial software, to enhance the utility of intensity data through a variety of "normalization", "correction", or "calibration" techniques, the current situation is complicated by a lack of standardization, as well as confusing, inconsistent use of terminology. In this paper, we first provide an overview of basic principles of LIDAR intensity measurements and applications utilizing intensity information from terrestrial, airborne topographic, and airborne bathymetric LIDAR. Next, we review effective parameters on intensity measurements, basic theory, and current intensity processing methods. We define terminology adopted from the most commonly-used conventions based on a review of current literature. Finally, we identify topics in need of further research. Ultimately, the presented information helps lay the foundation for future standards and specifications for LIDAR radiometric calibration. [ABSTRACT FROM AUTHOR]

3D Face model reconstruction from a single 2D image is fundamentally important for face recognition because the 3D model is invariant to changes of viewpoint, illumination, background clutter and occlusions. In this paper, an efficient 3D Face Reconstruction algorithm is proposed based on multi-view 2D images of human face based on similarity transform measurements. In this algorithm, the pose and depth estimation from 2D feature points of the respective face images is considered as an optimization problem and solved using Differential Evolution optimization. Further different strategies of differential evolution are used to optimize and the results are compared. Simple model integration method is proposed to improve the estimation accuracy of the 3D structure of face, when more than one non-frontal-view face images are available. Furthermore, Pearson Linear Correlation is computed to show the efficiency of the proposed approach. Experimental results on 2D Head Pose and 3D Bosphorus databases demonstrate the feasibility and efficiency of the proposed methods. [ABSTRACT FROM AUTHOR]

This emerging technology report describes virtual environment interactions an approach for blending movement and computer programming as an embodied way to support girls in building computational thinking skills. The authors seek to understand how body syntonicity might enable young learners to bootstrap their intuitive knowledge in order to program a three-dimensional character to perform movements. We have gained insight into the desire for character realism. The lessons learned to date, as well as the challenges to integrating the physical and virtual and keeping the interactions rich are discussed. [ABSTRACT FROM AUTHOR]

The paper presents the application results of reverse engineering technology for planning the plastic surgery. First step is digitalization of the patient body. It is realized by 3D structured light scanner. The scanning data are transferred into 3dsMax software and used for planning plastic surgery. The planning effect is shown using stereoscopy visualization method. [ABSTRACT FROM AUTHOR]

The article discusses the research study conducted by using three dimensional (3D) surface scanning for matching facial shapes against altered exhumed in the context of forensic individual identification. Topics discussed include improve the development and conservation of the National Museum of Natural History collections, evaluation of facial proportionality, and using professional image computer programs.

This paper presents an approach for a virtual guide for 3D scenes. The ontology assistance is a collaboration of a web-based virtual museum and a semantic database management system. The application proposed in this paper is a module from Conservation Space - an open source software application that addresses a core need of the conservation community in the National Gallery of Art, Washington D.C., USA. [ABSTRACT FROM AUTHOR]

Learning in immersive 3D environments allows students to collaborate, build, and interact with difficult course concepts. This case study examines the design and development of the TransGen Island within the SciEthics Interactive project, a National Science Foundation-funded, 3D virtual world emphasizing learning science content in the context of ethical dilemmas. The 2 year development process is examined through the lens of the rapid prototyping instructional design model, following the project from conceptualization to implementation of a 3D simulation. Through expert interviews, focus groups, and working groups, we were able to determine critical scientific and ethical issues to present to learners in the virtual world. We collected data on 53 students using the simulation at universities in the United States and South Africa and evaluated their experience using qualitative and quantitative methods. Results showed that student participants were engaged and motivated by the simulation. The students reported an increase in science knowledge and ethical understanding, but individual experiences varied. [ABSTRACT FROM AUTHOR]

The article presents a hardware-software system for people counting based on analysis of 3D information. It consists of a 3D video source (3D camera), an FPGA evaluation board and a PC computer. The computationaly demanding disparity map calculation and median filtering are realized in hardware. The software part is responsible for people segmentation, tracking and counting. The data between system nodes is transferred via Ethernet. In the paper the system architecture, proposed algorithms and obtained results are presented. [ABSTRACT FROM AUTHOR]

His research focuses on various parts of the open source and scientific computing ecosystems, including the Jupyter & IPythonprojects. MASSIMO DI PIERRO is currently a professor of computer science with DePaul University. GUESTEDITORS'INTRODUCTION JupyterinComputationalScience HansFangohr,MaxPlanckInstitutefortheStructureandDynamicsofMatter,Hamburg,22761,Germany ThomasKluyver,EuropeanXFEL,Schenefeld,22869,Germany MassimoDiPierro,DePaulUniversity,Chicago,IL,60604,USA N otebook interfaces - documents combining executablecodewithoutputandnotes - first became popular as part of computational mathematics software such as Mathematica and Maple. [Extracted from the article]

Direct digital manufacturing is a set of rapidly evolving technologies that provide easy ways to manufacture highly customized and unique products. The development pipeline for such products is radically different from the conventional manufacturing pipeline: 3D geometric models are designed by users often with little or no manufacturing experience, and sent directly to the printer. Structural analysis on the user side with conventional tools is often unfeasible as it requires specialized training and software. Trial-and-error, the most common approach, is time-consuming and expensive. We present a method that would identify structural problems in objects designed for 3D printing based on geometry and material properties only, without specific assumptions on loads and manual load setup. We solve a constrained optimization problem to determine the "worst" load distribution for a shape that will cause high local stress or large deformations. While in its general form this optimization has a prohibitively high computational cost, we demonstrate that an approximate method makes it possible to solve the problem rapidly for a broad range of printed models. We validate our method both computationally and experimentally and demonstrate that it has good predictive power for a number of diverse 3D printed shapes. [ABSTRACT FROM AUTHOR]

We present techniques for automatically parsing existing sewing patterns and converting them into 3D garment models. Our parser takes a sewing pattern in PDF format as input and starts by extracting the set of panels and styling elements (e.g. darts, pleats and hemlines) contained in the pattern. It then applies a combination of machine learning and integer programming to infer how the panels must be stitched together to form the garment. Our system includes an interactive garment simulator that takes the parsed result and generates the corresponding 3D model. Our fully automatic approach correctly parses 68% of the sewing patterns in our collection. Most of the remaining patterns contain only a few errors that can be quickly corrected within the garment simulator. Finally we present two applications that take advantage of our collection of parsed sewing patterns. Our garment hybrids application lets users smoothly interpolate multiple garments in the 2D space of patterns. Our sketch-based search application allows users to navigate the pattern collection by drawing the shape of panels. [ABSTRACT FROM AUTHOR]

Creative pattern cutting is a design process that can be integrated with digital technology. This paper examines how technology has the potential to change and innovate design and subsequently pattern cutting. It investigates the relationship between design and technology. It illustrates the way in which a number of designers have successfully integrated various three-dimensional (3D) software packages into their creative practices. The aim is to explore in detail the authors design methodology for her Masters collection, where 3D software intended for industrial design was used to generate complex mathematical surfaces to which a ‘flattening’ process was then applied. The flat patterns were extracted for further manipulation and experimentation with fabric and scale in relation to the body. The practical, experimental and traditional process of cutting is retained, with the aid of technology, to spark ideas for design and creative pattern development. [ABSTRACT FROM AUTHOR]

This paper presents the design optimization of a new type of roller vibration with amplitudes varying with software NX 7.5. The 3D modeling has been developed optimizing constructive solution, minimizing implementation costs in production. [ABSTRACT FROM AUTHOR]

This paper aims at presenting a comparative study of the "Shell" command / control which generates bodies with thin walls or some equivalent commands to be found in the following design software packages: Mechanical Desktop 6 or NX and Solid Edge 7.5 v.20. In other words all these variants of the basic command are comparatively approached, as they are likely to produce cavities and their features are particularly highlighted. [ABSTRACT FROM AUTHOR]