Advanced Graphics Research Articles

Mobile Ultrasound Plane Wave Beamforming on iPhone or iPad using Metal- based GPU Processing

Mobile and cost effective ultrasound devices are being used in point of care scenarios or the drama room. To reduce the costs of such devices we already presented the possibilities of consumer devices like the Apple iPad for full signal processing of raw data for ultrasound image generation. Using technologies like plane wave imaging to generate a full image with only one excitation/reception event the acquisition times and power consumption of ultrasound imaging can be reduced for low power mobile devices based on consumer electronics realizing the transition from FPGA or ASIC based beamforming into more flexible software beamforming. The massive parallel beamforming processing can be done with the Apple framework “Metal” for advanced graphics and general purpose GPU processing for the iOS platform. We were able to integrate the beamforming reconstruction into our mobile ultrasound processing application with imaging rates up to 70Hz on iPad Air 2 hardware.

Heatmap3: an improved heatmap package with more powerful and convenient features

Background Heat map and clustering are used frequently in expression analysis studies for data visualization. Simple clustering and heat map can be produced from the “heatmap” function in R language. However, it has some limitations in producing advanced graphics and is not highly customizable. Thus, we developed an R package heatmap 3 which significantly improves the original heatmap by adding more powerful and convenient features and providing a highly customizable interface.

Multiuser-centered resource scheduling for collaborative display wall environments

The popularity of large-scale, high-resolution display walls, as visualization endpoints in eScience infrastructure, is rapidly growing. These displays can be connected to distributed computing resources over high-speed network, providing effective means for researchers to visualize, interact with, and understand large volumes of datasets. Typically large display walls are built by tiling multiple physical displays together and running a tiled display wall required a cluster of computers. With the advent of advanced graphics hardware, a single computer can now drive over a dozen displays, thereby greatly reducing the cost of ownership and maintenance of a tiled display wall system. This in turn enables a broader user base to take advantage of such technologies. Since tiled display walls are also well suited to collaborative work, users tend to launch and operate multiple applications simultaneously. To ensure that applications maintain a high degree of responsiveness to the users even under heavy use loads, the display wall must now ensure that the limited system resources are prioritized to maximize interactivity rather than thread-level fair sharing or overall job-completion throughput. In this paper, we present a new resource scheduling scheme that is specifically designed to prioritize responsiveness in collaborative large display wall environments where multiple users can interact with multiple applications simultaneously. We evaluate our scheduling scheme with a user study involving groups of users interacting simultaneously on a tiled display wall with multiple applications. Results show that our scheduling framework provided a higher frame-rate for applications, which led to a significantly higher user performance (approx. 25%) in a target acquisition test when compared against traditional operating system scheduling scheme.

Myological reconstruction of the pelvic girdle of Anhanguera piscator (Pterosauria: Pterodactyloidea) using three-dimensional virtual animation

Despite muscular reconstructions of fossil vertebrates that have been performed for many years, sites of origin and attachment of muscles are rarely visible because their preservation on bones relies upon favorable circumstances. Limited attempts at reconstructing the pelvic muscles of pterosaurs have been made, but there is no report in the literature concerning a full detailed description of the pelvic girdle musculature of these fl ying reptiles. Thus, the aim of this study is to perform the reconstruction of the pelvis and hind limb myology in Anhanguera piscator Kellner & Tomida using the Extant Phylogenetic Bracket Method and advanced three-dimensional computer graphics, a methodological approach that has not yet been used for this purpose. Each muscle from the dorsal and ventral groups was individually reconstructed and outlined in the osteological model as lines whose ends represent their sites of origin and attachment in the bone. The authors used the Extant Phylogenetic Bracket Method to study these muscles in a more detailed way considering their divisions, such as Mm. iliotibiales 1-3, M. iliofemoralis externus/M. iliotrochantericus caudalis, and Mm. fl exores tibiales internus 1-4.

Increasing the Effective Span of Control: Advanced Graphics for Proactive, Trend-Based Monitoring

OCCUPATIONAL APPLICATIONS Legacy status display formats limit the number of processes that human operators can effectively and proactively monitor. Through a design approach targeting the needs of human attention, a novel trend–icon hybrid status display format (Trendicon; patent pending; Fisher Rosemount Systems, Inc., Round Rock, TX) was developed for proactive monitoring. An experiment contrasting Trendicons with digital values and trend graphs revealed that after minimal training, Trendicons supported earlier problem detections and more frequent proactive detections. Further, Trendicons led to a roughly fivefold increase in process indicators that participants could effectively oversee. Practical implications include earlier problem detection, improved system operation, and an increased operator span of control. Participants’ incorrect initial intuitions about display effectiveness highlight potential pitfalls of flexible, configurable displays. Trendicons are being developed for process and military control displays. The attention management design approach taken here is applicable to the design of supervisory status views for display-mediated work domains.TECHNICAL ABSTRACT Background: Process control operators rely heavily on their visual displays to monitor and stay abreast of processes and situations, anticipate future status, and proactively detect and resolve emerging problems. However, fielded status displays support only a subset of these tasks and can engender reactive rather than proactive monitoring because of inadequate attention management. Reactive monitoring is a significant barrier to effective operations and increasing operator span of control. Purpose: The benefits of an attention management design approach are demonstrated through the development and evaluation of a novel trend–icon hybrid (Trendicon) display format to support proactive monitoring. Methods: A within-subjects experiment contrasted the effectiveness of three status indicator formats—digital values, trend graphs, and Trendicons—in supporting proactive detection of emerging deviations. Span of control was assessed by varying the number of concurrently monitored status indicators (4, 12, and 24). Participants’ intuitions and preferences for the indicator formats were assessed as a proxy for display configuration choices. Results: Monitoring was largely reactive for digital values and trend graphs. In contrast, Trendicons promoted earlier problem detections and more frequent proactive detections, leading to a nearly fivefold increase in effective span of control. However, participants initially underestimated the utility of Trendicons. Conclusions: By explicitly designing attention management into new representations of process status, a dramatic increase in effective span of control was achieved over legacy formats. Better allocation of limited attentional resources during monitoring helped shift the nature of monitoring from reactive to proactive. Miscalibrated performance intuitions and preferences demonstrate that designers must consider both performance and user beliefs about display effectiveness. Development of Trendicons is ongoing in process and military control display applications. Designing for and addressing the underlying cognitive challenges of display-mediated supervisory control can result in more effective system operation, safer management of abnormal situations, and increased productivity.

A novel approach for integrative studies on neurodegenerative diseases in human brains

Despite a massive research effort to elucidate Alzheimer's disease (AD) in recent decades, effective treatment remains elusive. This failure may relate to an oversimplification of the pathogenic processes underlying AD and also lack of understanding of AD progression during its long latent stages. Although evidence shows that the two specific neuropathological hallmarks in AD (neuronal loss and protein accumulation), which are opposite in nature, do not progress in parallel, the great majority of studies have focused on only one of these aspects. Furthermore, research focusing on single structures is likely to render an incomplete picture of AD pathogenesis because as AD involves complete brain networks, potential compensatory mechanisms within the network may ameliorate impairment of the system to a certain extent. Here, we describe an approach for enabling integrative analysis of the dual-nature lesions, simultaneously, in all components of one of the brain networks most vulnerable to AD. This approach is based on significant development of methods previously described mainly by our group that were optimized and complemented for this study. It combines unbiased stereology with immunohistochemistry and immunofluorescence, making use of advanced graphics computing for three-dimensional (3D) volume reconstructions. Although this study was performed in human brainstem and focused in AD, it may be applied to the study of any neurological disease characterized by dual-nature lesions, in humans and animal models. This approach does not require a high level of investment in new equipment and a significant number of specimens can be processed and analyzed within a funding cycle.

Communication Platform for Image Analysis and Sharing in Biology

Image analysis is crucial to medical and biological applications. Recent advances in imaging technology have led to the demand for processing and visualizing a large amount of three-dimensional (3D) biomedical images. In addition, cloud computing has become popular for managing big data. Unfortunately, conventional image-processing systems either lack cloud computing services or advanced 3D processing abilities. In this paper, we present a novel cloud-based system for sharing, processing, and visualizing 3D biomedical images. Our system employs a standard web browser as a client interface that interactively communicates with high-performance servers. Thus, an inexpensive tablet PC without an advanced graphics processing unit (GPU) can be used for 3D image processing and visualization. Our system provides the sharing of limited software and hardware resources, and it allows for effective collaboration between researchers. We demonstrate the applicability and functionality of the system by examining typical case studies on biomed- ical images. We also examine the performance of our system numerically.Â

Fast Closed-Form Matting Using a Hierarchical Data Structure

Image/video matting is one of the key operations in many image/video editing applications. Although previous methods can generate high-quality matting results, their high computational cost in processing high-resolution image and video data often limits their usability. In this paper, we present a unified acceleration method for closed-form image and video matting using a hierarchical data structure, which achieves an excellent compromise between quality and speed. We first apply a Gaussian KD tree to adaptively cluster the input high-dimensional image and video feature space into a low-dimensional feature space. Then, we solve the affinity-weighted Laplacian alpha matting in the reduced feature space. The final matting results are derived using detail-aware alpha interpolation. Our algorithm can be fully parallelized by exploiting advanced graphics hardware, which can further accelerate the matting computation. Our method accelerates existing methods by at least an order of magnitude with good quality, and also greatly reduces the memory consumption. This acceleration strategy is also extended to support other affinity-based matting approaches, which makes it a more general accelerating framework for a variety of matting methods. Finally, we apply the presented method to accelerate image and video dehazing, and image shadow detection and removal.

Visualization of multidimensional numerical arrays of solid-state objects

This article is intended for math and computer science subjects study deepening and understanding of multidimensional computer graphics environment. The paper describes multidimensional numeric arrays visualization using object-oriented programming tools. The method allows the multidimensional numeric arrays stored data to simulate virtual reality products which, in turn, can become the reference now intensively developed new embedded system components. Shown an another option to simulate the multidimensional visual objects that may be transformed from capturing or graphically present on the computer screen using a new computational mathematics packages for solving advancedcomputer graphics tasks. It seems comfortable to use new estimated mathematics programs and packages, which already are enriched with digital image processing tools, allowing create a various objects of the real world.

Impact of computer graphics on the engineering product design: Conceptual analysis

Computer graphics matured over many years and played an important role in the development of engineering products like automotive and aircraft components. The current CAX (CAD/CAM/CAE) tools use computer graphics extensively, while helping in conceiving better designs with improved quality. Nowadays, engineering product development is being done concurrently and collaboratively, due to the advances in computer graphics. This paper presents a brief overview on evolution of computer graphics over the decades and its impact on the engineering product development. Conceptual analysis is done in order to find out the impact of computer graphics on engineering product development. It also attempts to present, how advances in computer graphics, have revolutionized the current engineering product development and what future technologies will offer. Key words: Computer graphics, engineering product development, computer graphic sciences.

Modeling Curiosity-Related Emotions for Virtual Peer Learners

With the advances in computer graphics, communication technologies and networking, virtual worlds are rapidly becoming part of the educational technology landscape [1]. Dede [2] suggests that the immersive interfaces offered by virtual worlds can promote learning, by enabling the design of educational experiences that are challenging or even impossible to duplicate in real world. In recent years, the usage of virtual worlds within the educational context is growing quickly. The New Media Consortium (NMC) Annual Survey on Second Life (SL) received 170% increase in response rate between 2007 and 2008. They also found that many of the educators who earlier used the existing SL, have started creating their own virtual worlds in less than a year's time [3].

Study on Drivers’ Comprehension of Advanced Graphical Route Information Panel Considering Individual Attributes

Graphical route information panels (GRIPs) have been commonly used on expressways in Japan to provide drivers with en-route traffic information. Although GRIPs have many advantages over variable message signs (VMSs), too much information and too complex displays may prevent drivers from properly understanding of the provided information. This study proposes advanced GRIPs in which LED displays showing pictograms and moving symbols are installed to assist drivers’ comprehension. The following results were obtained from an online survey conducted to investigate the impact of LED displays: (i) pictograms and moving symbols are helpful to most drivers to correctly understand the event information on GRIPs, but at the same time, they prevent drivers from understanding the travel time information; (ii) in terms of drivers’ comprehension there is a possibility to provide information about natural events (fog and tidal wave) by displaying pictograms or moving symbols on GRIPs.

Pixel programming aspects of digital image

This article describes a realization of the mathematics and informatics subjects by using visual objective programming facilities. For solving advanced computer graphics tasks, seems comfortable to use new estimated mathematics programs and packages, which already are enriched with digital image processing tools, allowing to create, paint and animate a various objects of the real world on computer screen, to extend the products of virtual reality. The described image reconstructionalgorithms have been evaluated on the basis of computer simulations.

New data visualization of the LHC Era Monitoring (Lemon) system

In the last few years, new requirements have been received for visualization of monitoring data: advanced graphics, flexibility in configuration and decoupling of the presentation layer from the monitoring repository. Lemonweb is the data visualization component of the LHC Era Monitoring (Lemon) system. Lemonweb consists of two subcomponents: a data collector and a web visualization interface. The data collector is a daemon, implemented in Python, responsible for data gathering from the central monitoring repository and storing into time series data structures. Data is stored on disk in Round Robin Database (RRD) files: one file per monitored entity, with set of entity related metrics. Entities may be grouped into a hierarchical structure, called “clusters” and supporting mathematical operations over entities and clusters (e.g. cluster A + cluster B /clusters C – entity XY). Using the configuration information, a cluster definition is evaluated in the collector engine and, at runtime, a sequence of data selects is built, to optimize access to the central monitoring repository. In this article, an overview of the design and architecture as well as highlights of some implemented features will be presented.

Sustain: An experimental test bed for building energy simulation

Current building energy simulation technology requires extensive labor, time and expertise to create building energy models, substantial computational time for accurate simulations, and generates data in formats that make results difficult to interpret. These deficiencies can be ameliorated using modern graphical user interfaces and algorithms which take advantage of modern computer architectures and display capabilities. This paper describes a novel test bed environment which offers an interactive graphical interface, provides access to simulation modules that run at accelerated computational speeds, and presents new graphic visualization methods for the interpretation of simulation results. Its modular structure makes it suitable for use in early stage building design, for use as a research platform for the investigation of new simulation methods, and for use as a tool for teaching concepts of sustainable design. Improvements in the accuracy and execution speed of many of the simulation modules are based on the modification of advanced computer graphics rendering algorithms. Significant performance improvements are illustrated in several computationally expensive energy simulation modules.

TOPAS: An innovative proton Monte Carlo platform for research and clinical applications

While Monte Carlo particle transport has proven useful in many areas (treatment head design, dose calculation, shielding design, and imaging studies) and has been particularly important for proton therapy (due to the conformal dose distributions and a finite beam range in the patient), the available general purpose Monte Carlo codes in proton therapy have been overly complex for most clinical medical physicists. The learning process has large costs not only in time but also in reliability. To address this issue, we developed an innovative proton Monte Carlo platform and tested the tool in a variety of proton therapy applications. Our approach was to take one of the already-established general purpose Monte Carlo codes and wrap and extend it to create a specialized user-friendly tool for proton therapy. The resulting tool, TOol for PArticle Simulation (TOPAS), should make Monte Carlo simulation more readily available for research and clinical physicists. TOPAS can model a passive scattering or scanning beam treatment head, model a patient geometry based on computed tomography (CT) images, score dose, fluence, etc., save and restart a phase space, provides advanced graphics, and is fully four-dimensional (4D) to handle variations in beam delivery and patient geometry during treatment. A custom-designed TOPAS parameter control system was placed at the heart of the code to meet requirements for ease of use, reliability, and repeatability without sacrificing flexibility. We built and tested the TOPAS code. We have shown that the TOPAS parameter system provides easy yet flexible control over all key simulation areas such as geometry setup, particle source setup, scoring setup, etc. Through design consistency, we have insured that user experience gained in configuring one component, scorer or filter applies equally well to configuring any other component, scorer or filter. We have incorporated key lessons from safety management, proactively removing possible sources of user error such as line-ordering mistakes. We have modeled proton therapy treatment examples including the UCSF eye treatment head, the MGH stereotactic alignment in radiosurgery treatment head and the MGH gantry treatment heads in passive scattering and scanning modes, and we have demonstrated dose calculation based on patient-specific CT data. Initial validation results show agreement with measured data and demonstrate the capabilities of TOPAS in simulating beam delivery in 3D and 4D. We have demonstrated TOPAS accuracy and usability in a variety of proton therapy setups. As we are preparing to make this tool freely available for researchers in medical physics, we anticipate widespread use of this tool in the growing proton therapy community.

SPIDERGL: A GRAPHICS LIBRARY FOR 3D WEB APPLICATIONS

Abstract. The recent introduction of the WebGL API for leveraging the power of 3D graphics accelerators within Web browsers opens the possibility to develop advanced graphics applications without the need for an ad-hoc plug-in. There are several contexts in which this new technology can be exploited to enhance user experience and data fruition, like e-commerce applications, games and, in particular, Cultural Heritage. In fact, it is now possible to use the Web platform to present a virtual reconstruction hypothesis of ancient pasts, to show detailed 3D models of artefacts of interests to a wide public, and to create virtual museums. We introduce SpiderGL, a JavaScript library for developing 3D graphics Web applications. SpiderGL provides data structures and algorithms to ease the use of WebGL, to define and manipulate shapes, to import 3D models in various formats, and to handle asynchronous data loading. We show the potential of this novel library with a number of demo applications and give details about its future uses in the context of Cultural Heritage applications.

Visual Analysis in Reference Management Software

This paper deals with representation of scientific references’ data and visual analysis of this data using web based scientific reference management software. The Reference application, is a web based reference management software, that enables easy administration and management of authors and scientific references. Similar web based reference management systems additionally support advanced tools for data visualization and exploration but the downside of this solutions is that they require installation of additional plugins due to the fact that visualization within the web browsers requires advanced graphics capabilities thus limiting the usability of these applications. The Reference application on the other hand introduces a solution for data visualization and exploration that relies on extensive usage of the latest HTML5 web standard featuring support for rich graphic intensive web applications hence forcing maximum usability and compatibility with the modern web browsers. This paper describes the visualization tool within Reference application, its implementation and functionalities.

3D Visualization of Urban Data Based on CityGML with WebGL

Due to the advances in computer graphics and improved network speed it is now possible to navigate in 3D virtual world in real time. Until now, technologies employed require to install standalone application or plugins on navigators. The arrival of HTML 5 brings news solutions to visualize 3D data in a browser with WebGL. Several globe projects have proven that such technologies can be employed. Unfortunately, demonstrations are often based on proprietary formats to exchange or to store data. In this work, we propose to use CityGML: a standard provided by the Open Geospatial Consortium. CityGML files are imported in our Environment Editor. With several tools that we present in this paper, data are processed and stored. A client server application is also presented to permit the visualization of geometry and semantic in a navigator.

SU-E-T-473: Performance Assessment of the TOPAS Tool for Particle Simulation for Proton Therapy Applications.

The TOPAS Tool for Particle Simulation was developed to make Geant4 Monte Carlo simulation more readily available for research and clinical physicists. Before releasing this new tool to the proton therapy community, several test have been performed to ensure accurate simulations in a variety of proton therapy setups. TOPAS can model a passive scattering or scanning beam treatment head, model a patient geometry based on CT images, score dose, fluence, etc., save and replay a phase space, provides advanced graphics, and is fully four-dimensional (4D) to handle variations in beam delivery and patient geometry during treatment. An innovative control system meets requirements for ease of use, reliability and repeatability without sacrificing flexibility. To test the TOPAS code, we modeled proton therapy treatment examples including the UCSF eye treatment beamline (UCSFETB), the MGH STAR radiosurgery beamline and the MGH gantry treatment head in passive scattering and scanning modes. The simulations included time-dependent geometry and time- dependent beam current delivery. At the UCSFETB, time- dependent depth dose distributions were accurately simulated with time- varying energy modulation from a rotating propeller. At the MGH STAR beamline, distal and proximal ranges agreed within measurement uncertainty and the shape of the simulated SOBP followed measured data. For the MGH gantry treatment head in passive scattering mode, SOBPs were simulated for the full set of range modulator wheel and second scatterer combinations. TOPAS simulation was within clinical required accuracy. For the MGH nozzle in scanning mode, a variety of scan patterns were simulated with fluence maps generated for cases including beam current modulation, energy modulation and target tracking. Our results demonstrate the functionality of TOPAS. They show agreement with measured data and demonstrate the capabilities of TOPAS in simulating beam delivery in 3D and 4D. This work was supported by IH/NCI under R01 CA 140735-01.